Branched-chain fatty acids(BCFAs)are new bioactive fatty acids with anti-inflammatory properties.However,the role of BCFAs in alleviating ulcerative colitis has not been clarified.Herein,we evaluated the protective ef...Branched-chain fatty acids(BCFAs)are new bioactive fatty acids with anti-inflammatory properties.However,the role of BCFAs in alleviating ulcerative colitis has not been clarified.Herein,we evaluated the protective effect of BCFAs from goat milk in mice with colitis induced using dextran sodium sulfate(DSS)and explored the corresponding mechanism.These results show that BCFAs extracted from goat milk can significantly alleviate weight loss in mice,and reduce the disease activity index and the activity of myeloperoxidase while increasing the content of antioxidant enzymes in colon tissue and reducing the oxidation stress response.These data also show that BCFAs can down-regulate the gene and protein expression of the toll-like receptor 4(TLR4)/nuclear factorκB p65(NF-κB p65)/NOD-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathway,and at the same time significantly reduce the expression of pro-inflammatory factors tumor necrosis factorα(TNF-α),interleukin 1β(IL-1β),and IL-18 in colon tissue,and significantly increase the expression of the anti-inflammatory factor IL-10.In conclusion,these results demonstrated that BCFAs in goat milk exerted effects on colitis-related inflammatory cytokines and inhibited inflammation by inducing the TLR4/NF-κB/NLRP3 pathway to alleviate DSS-induced ulcerative colitis.This study provides evidence for the potential of BCFAs as bioactive fatty acids in food products and to ameliorate ulcerative colitis development in mice.展开更多
The search for functional foods with health benefits has increased,and yogurt represents one of these products due to their properties,such as,source of probiotics that favour the gastrointestinal system,contains vita...The search for functional foods with health benefits has increased,and yogurt represents one of these products due to their properties,such as,source of probiotics that favour the gastrointestinal system,contains vitamins,minerals and improves the action of enzymes.Present work investigated bromatological,microbiological,sensorial properties and shelf-life of different yogurt goat milk formulations with Aloe vera and natural sweeteners.The goat yogurt with 99.40%A.vera pulp and 0.60%S.rebaudiana presented the best nutritional composition,being suitable for human consumption representing an innovative product with a great functional potential.The synergy between the ingredients used in the yogurt processing resulted in an innovative product to the market.Goat milk has a lower cost per liter in comparison with cow milk,Aloe vera is accessible due to its fast-vegetative propagation,Stevia Rebaudiana has a great popularity for being a natural sweetener with no calories,and all these products are produced in México.展开更多
Lactic acid bacteria (LAB) is widely used as culture starters in dairy fermentation. The aim of this study was to investigate the quality of fermented goat milk and cow milk, as well as the viability of LAB in the s...Lactic acid bacteria (LAB) is widely used as culture starters in dairy fermentation. The aim of this study was to investigate the quality of fermented goat milk and cow milk, as well as the viability of LAB in the same products. Fermentations were performed with pasteurized goat milk or cow milk added with skim milk (18% of solids) using three separately different starters; yoghurt starter (a combination of Streptococcus thermophilus FNCC-0040 and Lactobacillus bulgaricus FNCC-0041), single starter of Lactobacillus acidophilus FNCC-0029 and Lactobacillus casei FNCC-0051. The parameters observed were pH, acidity, nutritional quality including protein, fat and lactose content and product's viscosity. Acidity, pH and viability of LAB were also monitored during storage at refrigerated temperature (4 ℃) for 28 days. Results show that the different LAB starters did not affect the pH, acidity, lactose and protein content. Differences on LAB starters affected fat content and viscosity. The highest score of viscosity (30.00 Pa.s ± 7.02 Pa.s) was observed on products fermented by yoghurt starters, followed by products obtained using starter of L. acidophilus (17.7 ±11.4) and L. casei (8.62 ±0.35). Protein content, acidity, pH and viscosity were not significantly different between products obtained from goat milk and cow milk. Fat content in fermented goat milk was higher (5.03% ±0.62%) than in fermented cow milk (3.52% ±0.37%), however, lactose content was higher in fermented cow milk (5.16% ±0.40%) than in fermented goat milk (4.53% ±0.35%). Total LAB concentration in fermented cow milk during storage was 8.03± 0.52 logt0 cfu/mL, while in fermented goat milk was 7.81 loglo cfu/mL ± 0.67 loglo cfu/mL. There was a 10.83% decrease in LAB viability in fermented cow milk and 11.40% in fermented goat milk after 28 days of storage. In conclusion, quality of fermented milk is affected by the starters applied, raw milk source and storage period.展开更多
[Objectives]To amplify and identify the specific gene fragments of cattle and sheep by real-time fluorescence-based PCR,and quickly and accurately identify the adulteration problem of goat milk powder according to the...[Objectives]To amplify and identify the specific gene fragments of cattle and sheep by real-time fluorescence-based PCR,and quickly and accurately identify the adulteration problem of goat milk powder according to the differences of mitochondrial genes among different species.[Methods]The specificity,limit of detection and repeatability test were carried out by isolating somatic cells,extracting template DNA and determining the reaction conditions of real-time fluorescence-based PCR.[Results]The real-time fluorescence-based PCR method could be used to identify the bovine and ovine-derived materials of milk powder with high specificity,high sensitivity and good repeatability,and the limit of detection of milk components in goat milk powder could reach 0.01%.[Conclusions]The real-time fluorescence-based PCR method can be used to quickly and accurately detect the milk components in goat milk powder,and provide some technical support for the adulteration detection of dairy industry.展开更多
A cross-sectional study was carried out to assess handling and hygienic production practices of goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 120 households were purposively...A cross-sectional study was carried out to assess handling and hygienic production practices of goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 120 households were purposively selected for this study using a stratified sampling technique. The data were collected through the questionnaire, field observations, key informants interview and focus group discussions. The study showed that majority of the sampled households were illiterate. The goats were kept in an open kraal made of thorny acacia trees on an earthen floor that had no roof. The goats were milked inside these open kraals, and were sometimes contaminated with muck and animal dung mainly the rainy season which could raise the possibility of milk contamination & spoilage. Moreover, traditional hand milking was the only milking method and majority of the respondents didn’t wash their hands and the udder of the animal before milking, indicating low community awareness and knowledge of sanitary milk production procedures. Plastic equipment which is difficult to clean and can increase milk contamination and spoilage was used. About 43.3% of the pastoralists and 76.67% of the agro-pastoralists were cleaning milk vessels regularly. The most often used plant species for smoking milk handling equipment in the study area to extend shelf life and add flavor & aroma were Acacia ethaica, Blanites galabra, and Solanum Carense. The main constraints to hygienic goat milk in the area were identified to be poor barn hygiene, poor production procedures, disease, source of washing water and lack of extension services. In general, it can be concluded that handling and hygienic production practices of goat milk used in the study area were unsanitary, which may have been primarily caused by the community’s lack of awareness & understanding as well as a lack of supporting infrastructures. Therefore, the concerned bodies should place a high priority on the improvement of hygienic practices by carrying out various relevant development interventions, such as raising milk producers’ awareness, improving the health of goats, and providing the necessities for milk handling.展开更多
A cross-sectional study was carried out to evaluate microbiological quality of raw goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 40 pooled raw goat milk samples (each with a...A cross-sectional study was carried out to evaluate microbiological quality of raw goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 40 pooled raw goat milk samples (each with a volume of 450 mL) were collected from the udders and milk handling equipment of targeted goat milk producers in the study area. The milk samples were subjected to laboratory analysis to evaluate total bacterial count (TBC) and total coliform count (TCC) in order to determine the microbiological quality of the raw goat milk in the study area. The study showed that the mean total bacterial count (TBC) and total coliform count (TCC) for raw milk samples collected from the udder were 4.92 ± 0.23 and 2.68 ± 0.36 log<sub>10</sub> cfu·mL<sup>-1</sup>, respectively. The mean counts for samples collected from milk equipment were 5.61 ± 0.32 and 3.93 ± 0.21 log<sub>10</sub> cfu·mL<sup>-1</sup> for TBC and TCC, respectively. The values for the samples collected from pastoral production system were 5.63 ± 0.13 and 4.02 ± 0.20 log<sub>10</sub> cfu·mL<sup>-1</sup> for TBC and TCC, respectively. The average means of TBC and TCC for samples collected from the agro-pastoral production system were 4.9 ± 0.41 and 2.59 ± 0.37 log<sub>10</sub> cfu·mL<sup>-1</sup>, respectively. Significant difference (P 0.05) in mean TBC and TCC was observed between milk samples collected from pastoral and agro-pastoral production systems as well as milk samples collected from udders and milk handling equipment of the producers. It could be concluded that both TBC & TCC of goat milk samples collected from the udder as well as from the milk handling equipment of producers exceeded the acceptable limits. This indicated that production practices performed during milk production and postharvest handling in the study area were unhygienic. Therefore, hygienic and proper milk production procedures should be followed to improve the quality of goat milk for its intended use in the study area.展开更多
Goat milk ice cream was made with various sources of fat ingredients such as cream, soybean oil, rice bran oil and butter with the purpose of seeking the fat ingredient source instead of fat source from cow origin. Th...Goat milk ice cream was made with various sources of fat ingredients such as cream, soybean oil, rice bran oil and butter with the purpose of seeking the fat ingredient source instead of fat source from cow origin. The physical properties and the sensory evaluation of ice cream were then investigated. The firmness of goat milk ice cream mixed with rice bran oil, butter and cream were not significantly different before aging at 4 ℃ for 8 h. All of them gave the overrun between 51%-63% and the one with butter was the highest. The meltdown rate of all types of fat ingredients are not significantly different, being in the range of 0.86-0.88 g/min. According to sensory evaluation, the cow milk ice cream with cream was mostly accepted in all attributes such as appearance, smoothness, whiteness, melting in mouth and odor while the goat milk with cream and butter are the second and third. Nevertheless, the goat milk ice cream with soybean oil and rice bran oil were moderately accepted in overall preferences.展开更多
The proteins coming from the milk whey have numerous functional properties. Among the proteins with high bioactivity, α-lactoalbumin (α-La) and β-lactoglobulin (β-Lg) are present in large quantities in the milk wh...The proteins coming from the milk whey have numerous functional properties. Among the proteins with high bioactivity, α-lactoalbumin (α-La) and β-lactoglobulin (β-Lg) are present in large quantities in the milk whey. In the separation process of proteins, it is important to choose techniques which besides ensuring purity and high yield will not affect the molecule biological activity. The aqueous two-phase systems (ATS) have been utilized with success in the partition of these proteins, however, the studies were performed using protein in its pure form. Studies using milk whey in-nature and goat milk whey have not been found yet. In this context, the objective of this study was to evaluate the liquid liquid equilibrium of aqueous two-phase systems (ATS) in the partition of α-La and β-Lg from goat milk whey in-nature. Equilibrium data were performed considering ATS comprised of polyethylene glycol, potassium phosphate and water at 25°C and pH 7.0. The influence of the polymer molecular weight and amount of goat milk whey in-nature on the partition coefficient of these proteins were assessed. The partition coefficient, selectivity, process yield and purity of α-lactoalbumin and β-lactoglobulin proteins were determined. The results showed that the separation technique by aqueous biphasic systems is applicable indicating high efficiency in the whey proteins separation process.展开更多
Concentrations of 20 different minerals in commercial goat milk yogurt (CGY) and its cow milk yogurt (CCY) counterpart were evaluated in reference to goat milk yogurt manufactured from Fort Valley State University (FV...Concentrations of 20 different minerals in commercial goat milk yogurt (CGY) and its cow milk yogurt (CCY) counterpart were evaluated in reference to goat milk yogurt manufactured from Fort Valley State University (FVGY), Fort Valley, GA, USA. Three different lots of CGY and CCY each were purchased from local retail stores at Warner Robins, GA, and 3 batches of FVGY were made using goat milk from the University milking herd. All 3 types of experimental yogurts were stored at 4°C refrigerator for 4 weeks. Twenty major and trace minerals were analyzed by an Inductively Coupled Plasma Optical Emissions Spectrometer (Thermo Jarrel Ash Enviro 36, Worchester, MA), using argon as the carrier gas and the EPA method 6010. Total solids (TS) content (%) of FVGY, CGY and CCY products were 11.03, 13.1 and 11.3, respectively, indicating CGY had higher TS than the CCY and FVGY yogurt. Respective mean mineral concentrations (ppm, wet basis) of FVGY, CGY and CCY were: Ca 1057, 1162, 1160;P 838, 974, 929;K 1327, 1717, 1208;Mg 102, 133, 113;Na 545, 449, 475;Fe 4.28, 3.33, 2.11;Mn 0.24, 0.19, 0.13;Cu 10.5, 9.85, 7.22;Zn 17.5, 11.7, 11.8. Levels of all macro minerals except potassium were higher in commercial goat and cow yogurts than FVGY, which may be due to the higher TS contents. FVGY had higher Fe, Mn, Cu and Zn than both commercial products. The heavy metal (Pb, Cd and Ni) contents (ppm) appeared to be normal range, while Al contents of FVGY, CGY and CCY were 11.9, 8.66 and 7.65, respectively, which were higher than those of Pb, Cd and Ni. Both commercial products contained higher major mineral contents than the university yogurt, which might be attributable to the differences in diet, breed, and stage of lactation of milking animals, as well as the tapioca additive used in the commercial products.展开更多
Effects of frozen-storage on fatty acids profiles and basic nutrient contents of two types of low-fat caprine milk ice creams were investigated during 0, 2, 4, 8 weeks of storage at -18°C. Two types of the experi...Effects of frozen-storage on fatty acids profiles and basic nutrient contents of two types of low-fat caprine milk ice creams were investigated during 0, 2, 4, 8 weeks of storage at -18°C. Two types of the experimental low-fat soft-serve goat ice creams were manufactured using whole (full-fat) milk and 2% fat goat milk with addition of commercial powdered vanilla flavor pre-mix containing 0.25% fat (Alpha Freeze, D466-A9047, Tampa, FL, USA). Fatty acid concentrations were quantified using a Thermo Electronic gas chromatography (GC)-MS (Model TRACE GC Ultra, Austin, TX, USA) equiped with an automatic sampler (Model AS-3000, Thermo Electronic Co.). The results showed that fat content was the only basic nutrient component exhibited the difference between the two types of ice creams, while no other components have shown differences between the two low-fat ice creams during the storage periods. The level of lauric acid (C12:0) was the highest among all 16 fatty acids, followed by palmitic (C16:0), linoleic (C18:1), and myristic acid (C14:0). The high levels of the medium chain fatty acids (C12:0 and C14:0) might have been derived from the goat milk as well as the palm oil asa part of the ingredients in the commercial ice cream premix. Among long chain fatty acids, palmitic acid (C16:0) was the highest, followed by oleic acid (C18:1) and stearic acid (C18:0). All of the long chain fatty acids contents were significantly higher (P < 0.05 or 0.01) in whole milk ice cream than those in 2% fat ice cream, except for the C22:0 and C24:00 acids. It was concluded that mean levels of the individual fatty acids in the caprine ice creams were significantly influenced by the types of milk fat used in the ice creams, but not by storage periods and storage × fat type interaction effects.展开更多
The study of the triacylglycerols (TAG) by gas chromatography (GC) using capillary columns is an efficient technique for the determination of some characteristics of quality of fats and oils. The objective of the pres...The study of the triacylglycerols (TAG) by gas chromatography (GC) using capillary columns is an efficient technique for the determination of some characteristics of quality of fats and oils. The objective of the present study was to determine by GC the content of TAG present in fat of cow and goat milk produced in four zones of Mexico. According to criteria established in Mexican Standardization, 25 samples were obtained of 1 L of ultra-pasteurized cow milk (UHT) and 27 and 48 of raw cow and goat milk, respectively. The fat was extracted from all of the milk samples by detergent solution, and was stored at –20℃ until its analysis. The chromatographic conditions made it possible to identify and quantify TAG of 28 to 54 numbers of carbons, which were analyzed under descriptive and inferential statistical techniques. For the cow milk fat, the statistical analyses indicated significant difference (p < 0.05) in the TAG C34, C50 and C52, and for the goat milk fat in the TAG of C36 to C52. No equality of means was found among the TAG of the cow and goat milk fat. This study offers an advance in the characterization of the TAG present in the cow and goat milk fat produced in Mexico.展开更多
Differences in free fatty acid (FFA) compositions between low-fat (LF) and full-fat (FF: whole milk) goat cheeses were evaluated during 3 months at 4oC refrigeration. The two types of cheeses were manufactured using a...Differences in free fatty acid (FFA) compositions between low-fat (LF) and full-fat (FF: whole milk) goat cheeses were evaluated during 3 months at 4oC refrigeration. The two types of cheeses were manufactured using a bulk milk from the mixed herd of Saanen, Alpine, and Nubian goat breeds. LF cheeses were made using LF milk after cream separation. FFAs of all cheeses were extracted in diisoprophyl ether using polypropylene chromatography column, and FFA concentrations were quantified using a gas chromatograph equipped with a fused silica capillary column. Moisture, fat, protein contents (%) and pH of fresh LF and FF cheeses were: 55.1, 52.3;1.30, 25.6;35.7, 22.5;5.40, 5.42, respectively. The FFA contents (mg/g cheese) of fresh FF and LF cheeses prior to storage treatments for C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C18:0, C18:1, and C18:2 were: 0.020, 0.072;0.070, 0.035;0.061, 0.055;0.181, 0.167;0.073, 0.047;0.174, 0.112;0.579, 0.152;0.308, 0.202;0.521, 0.174;and 0.057, 0.026, respectively. The respective FFA to total fatty acid ratios for 0, 1 and 3 months aged FF and LF cheeses were 8.44, 12.4;6.31, 16.91;12.03, 14.19. The LF cheeses generated more FFA than FF cheeses, while actual FFA content in FF cheese was significantly higher than in LF cheese. The FFA contents of LF cheese at 0, 1 and 3 months storage were 48.0, 96.8 and 36.4% of those of FF cheese, respectively. It was concluded LF cheese generated higher amount of FFA than FF cheese, although total FFA content was significantly (P<0.05) lower in LF cheese than in FF cheese.展开更多
Camels’ milk (CM) and goats’ milk (GM) are rich in nutrients and vitamins necessary for the health of humans and have therapeutic properties as they are rich in antioxidants and have a protective role against free r...Camels’ milk (CM) and goats’ milk (GM) are rich in nutrients and vitamins necessary for the health of humans and have therapeutic properties as they are rich in antioxidants and have a protective role against free radicals that </span><span style="font-family:Verdana;">have harmful effects on human health. Date palm (DP), camels’ milk and </span><span style="font-family:Verdana;">goats’ milk have been reported to be used for the prevention and treatment of vari</span><span style="font-family:Verdana;">ous diseases in Arab countries. This study was designed to mix date palm</span><span style="font-family:Verdana;"> with camels’ milk and goats’. Eight formulations of both camels’ milk and goats’ were made from different percentages of date palm. These formulations were added at ratios of 0 (control), 10%, 20% and 30% (w/v) to camels’ milk and goats’ and the effect of this date palm on the composition and texture properties of the fermented obtained products were followed. It has been found that pH, protein, fat decreased and total solid, carbohydrate, ash, viscosity, vitamins, minerals and antioxidants increased with the increase of the added percentage of date palm compared to control. Microbial counts of the fermented camels’ milk (FCM) and goats’ milk (FGM) increased significantly (P < 0.05) with the addition of different formulations and during storage. Also, fermented camels’ milk (FCM) and fermented goats’ milk (FGM) fortified with different ratios date palm (DP) concentration resulted in good properties and higher acceptable sensory values (at a rate of 10% - 20%) in fresh and till the end of storage periods. The addition of the date palm to all treatments </span><span style="font-family:Verdana;">improved the composition, viscosity, microbiological quality of fermented</span> <span style="font-family:Verdana;">camels’ and goats’ milk with nutritional functional values and acceptable</span><span style="font-family:Verdana;"> sensory attributes.展开更多
Four non-pregnant multiparous lactating goats were used in a 4 × 4 latin square experiment in the present study. The four treatments were abomasal infusion of 0, 50, 100, and 150 g d^-1 glucose. The results showe...Four non-pregnant multiparous lactating goats were used in a 4 × 4 latin square experiment in the present study. The four treatments were abomasal infusion of 0, 50, 100, and 150 g d^-1 glucose. The results showed that graded glucose infusion increased milk yield (P 〈 0.01). The highest milk yield was observed when 50 g d^-1 glucose was infused. An infusion of glucose at 100 or 150 g d^-1 failed to increase milk yield further and milk yield of the 100 g d ^-1 glucose infusion treatment was even significantly lower than that of the 50 g d^-1 treatment (P 〈 0.01). Though milk fat content was gradually decreased by graded glucose infusions and milk fat yield of the 100 and 150 g d 1 treatments were lower than that of the control (P 〈 0.01); milk fat yield of the 50 g d i treatment was not depressed and was higher than that of the control (P 〈 0.01). Graded glucose infusion did not change the contents of milk protein and non-fatty solids. Yields of milk protein (P 〈 0.05), lactose (P 〈 0.01), non-fat solids (P 〈 0.01), and lactose content (P 〈 0.01) of the 50 g d^-1 treatment were higher than those of the control but had no difference among the other three treatments. Contents of those de novo synthesized fatty acids in milk fat remained unchanged or increased and those preformed fatty acids remained unchanged or decreased by graded glucose infusion. Glucose infusion decreased the total yields of C16 + C16:1 and 〉 C16 fatty acids and had no influence on the yield of C4-C14:1 fatty acids (P 〈 0.05). Results of the present study implied that increased glucose supply had positive effects on the production of milk, milk protein, milk fat, and lactose only when glucose was a limiting factor for milk synthesis. Excessive glucose supply had no further beneficial effects and might depress milk fat synthesis.展开更多
To research the relation among the erythrocytic membrane.liquidity and the contents of MDA, the activity of SOD in serum of the milk goat with fluorosis. An animal model with fluorosis was constructed, and the fluores...To research the relation among the erythrocytic membrane.liquidity and the contents of MDA, the activity of SOD in serum of the milk goat with fluorosis. An animal model with fluorosis was constructed, and the fluorescent probe technique of DPH was used to measue the erythrocytic membrane liquidity. At the same time, the contents of MDA and the activity of SOD in serum were measured. The results showed that the erythrocytic membrane liquidity in the control group and flurosis group were 5.6742 ± 0.4417 and 3.7248 ± 0.4521 (P 〈0.01) respectively, the contents of MDA in serum were 2.0408 ± 0.198 and 4.494± 0.438 (P 〈0.01) respectively, the activities of SOD were 175.638 ± 22.201 and 113.714 ± 34.258 (P 〈0.01) respectively. The correlation analysis indicated that the relation between the activity of SOD and the liquidity of erythrocytic membrane was positive correlation ( r= 0.7321, P 〈0.05), whereas the relation between the contents of MDA and the liquidity of erythrocytic membrane was negative correlation (r = -0.6438, P 〈0.01). The erythrocytic membrane liquidity decreased in milk goat with fluorosis, which played a role in the occurrence and development of the fluorosis. There was correlation among the erythrocytic membrane liquidity and the contents of MDA, the activity of SOD.展开更多
Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of ...Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet(35% concentrate, n = 5, LC) and there were two high-concentrate treatments(65% concentrate, HC), one fed a high concentrate diet for a long period(19 wks, n = 7, HL); one fed a high concentrate diet for a short period of time(4 wk, n = 5, HS). Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results: Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet(P 〈 0.01), while the percentage of milk fat was lower in the HL(P 〈 0.05) but not in the HS group. The total amount of saturated fatty acids(SFA) in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids(UFA) and monounsaturated fatty acids(MUFA) were markedly decreased in the HL group compared with the LC group(P 〈 0.05). Among these fatty acids, the concentrations of C15:0(P 〈 0.01), C17:0(P 〈 0.01), C17:1(P 〈 0.01), C18:1 n-9 c(P 〈 0.05), C18:3 n-3 r(P 〈 0.01) and C20:0(P 〈 0.01) were markedly lower in the HL group, and the concentrations of C20:0(P 〈 0.05) and C18:3 n-3 r(P 〈 0.01) were lower in the HS group compared with the LC group. However, the concentrations of C18:2 n-6 c(P 〈 0.05) and C20:4 n-6(P 〈 0.05) in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 & 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group(P 〈 0.05), and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group(P 〈 0.05). In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group(P 〈 0.05). The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group(P 〈 0.05).Conclusions: Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods.展开更多
Paired-like homeodomain transcription factor 1 (PITX1) plays an important role in pituitary development by indirectly regulating the expression of the GH and PRL genes, and therefore PITX1 gene is regarded as a pote...Paired-like homeodomain transcription factor 1 (PITX1) plays an important role in pituitary development by indirectly regulating the expression of the GH and PRL genes, and therefore PITX1 gene is regarded as a potential candidate gene for building the relationship between the gene polymorphism and milk traits. The aim of this study was to explore the novel genetic variant in PITX1 gene and its effect on milk performance in dairy goats. Herein, a novel genetic variation (NW_00314033: g.201GA or IVS1+41GA) located at nt41 position of the first intron of the goat PITX1 gene was reported at the P1 locus, which can be genotyped by the Msp I PCR-RFLP. In the Msp I PCR-RFLP analyis, the GG variant was a major genotype, and the A variant was a minor allele in Guanzhong dairy goats which was at Hardy-Weinberg disequilibrium (chi-square χ2=140, P0.01). The establishment of associations between different genotypes and milk performance was performed in the analyzed population. A total of three significant associations of the polymorphism with average milk fat content (%) (P=0.045), morning milk fat content (%) (P=0.049), and afternoon milk fat content (%) (P=0.050), were found, respectively. A significant relationship between the polymorphism and average total solid content (P=0.029) was also detected. This novel single nucleotide polymorphism (SNP) extended the spectrum of genetic variation of the goat PITX1 gene, and its significant association with milk performance would benefit from the application of DNA markers related to improving milk performance through marker-assisted selection (MAS) in dairy goats.展开更多
Lactic acid bacteria (LAB) were isolated from goat's milk in different north west region of Algeria. A total of 233 isolates were identified as LAB. However, only 11 strains showed excellent inhibition zones on aga...Lactic acid bacteria (LAB) were isolated from goat's milk in different north west region of Algeria. A total of 233 isolates were identified as LAB. However, only 11 strains showed excellent inhibition zones on agar when Salmonella lyphimorium ATCC 13311 was used as an indicator for preliminary detection of antagonistic activity. After elimination of inhibition due to acid and H202, Staphylococcus aureus ATCC 25923 was used for secondary screening for antagonistic activity of these 11 strains. It was found that only 9 strains exhibited a good inhibition zones on agar, and all of them could inhibit E. coli ATCC 25921 and Pseudomonas aeruginosa ATCC 27853 as the third and the forth indicators respectively. Lactococcus lactis subsp, cremoris, Lactobacillus casei subsp, casei, Lactobacillus casei subsp, rhamnosus, Streptococcus salivarius subsp, thermophilus and Lactococcus lactis biovar. diacetylactis were the strains that have a good antibacterial activity, survive in the gastrointestinal conditions and were sensible to the majority of the antibiotics. All isolated strains tolerate pH = 2 and high bile salt concentration.展开更多
Twenty-two lactic acid bacteria (LAB) strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermop...Twenty-two lactic acid bacteria (LAB) strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermophilus (UNSE314), Lactobacillus (L.) delbrueckii subsp, bulgaricus (UNSE309), L. rhamnosus (UNSE308), L. plantarum (UNSE287, UNSE316, UNSE317) and Pediococcus pentosaceus (UNSE315) strains presented high acidifying activity. All strains tested metabolized citrate and produced diacetyl-acetoin in goat milk. Based on these results, 10 strains with the best performance in diverse technological properties were selected to determine esterolytic activity. In all evaluated strains, esterase specific activity (ESA) was detected on ct-naphthyl (ct-NA) acetate and 13-naphthyl ([3-NA) acetate, propionate, eaprylate and ct-NA butyrate. No activity was detected on [3-NA laurate. The highest values were detected when using a-NA instead of fI-NA derivatives as substrate. In Pediocoecus strains, wide variability in ESA were observed, which were species- and strain-specific. These results allow us to select strains with biochemical properties and esterase activities to design starter and adjunct cultures that contribute to flavor development during cheese ripening, thus preserving the typical organoleptic characteristics of Argentinean goat cheeses.展开更多
The experiment was conducted to investigate the effect of transfer of PUFA protected and carnitin precursor on the ration of chemical composition of milk dairy goat. In total, 10 female dairy goats of 2 - 4 years old ...The experiment was conducted to investigate the effect of transfer of PUFA protected and carnitin precursor on the ration of chemical composition of milk dairy goat. In total, 10 female dairy goats of 2 - 4 years old Peranakan Etawah (PE) with body weight of 25 - 45 kg were used in this experiment. The feed material included a basal diet (control) based on yellow corn, rice bran, soya bean meal, coconut meal, tuna fish oil and lemuru fish oil. The method of the research was experimental in vivo using Randomized Completely Block Design (RCBD). There were 5 treatments in each experiment and 2 replications. The treatment consisted of P0 = control ration, P1 = P0 + 200 ppm L-carnitine on the ration, P2 = P1 + soya bean oil, P3 = P1 + protected tuna fish oil 5 ml or equal with 4% in the ration, and P4 = P1 + protected lemuru fish oil 5 ml or equal with 4% in the ration. The measured variable is chemical composition of milk dairy goat. The results of variance analysis showed that the effect of transfer of PUFA fatty acid in the rations contained 200 ppm L-carnitine significantly展开更多
基金financially supported by the 2021 Kabrita Nutrition Grant.
文摘Branched-chain fatty acids(BCFAs)are new bioactive fatty acids with anti-inflammatory properties.However,the role of BCFAs in alleviating ulcerative colitis has not been clarified.Herein,we evaluated the protective effect of BCFAs from goat milk in mice with colitis induced using dextran sodium sulfate(DSS)and explored the corresponding mechanism.These results show that BCFAs extracted from goat milk can significantly alleviate weight loss in mice,and reduce the disease activity index and the activity of myeloperoxidase while increasing the content of antioxidant enzymes in colon tissue and reducing the oxidation stress response.These data also show that BCFAs can down-regulate the gene and protein expression of the toll-like receptor 4(TLR4)/nuclear factorκB p65(NF-κB p65)/NOD-like receptor thermal protein domain associated protein 3(NLRP3)signaling pathway,and at the same time significantly reduce the expression of pro-inflammatory factors tumor necrosis factorα(TNF-α),interleukin 1β(IL-1β),and IL-18 in colon tissue,and significantly increase the expression of the anti-inflammatory factor IL-10.In conclusion,these results demonstrated that BCFAs in goat milk exerted effects on colitis-related inflammatory cytokines and inhibited inflammation by inducing the TLR4/NF-κB/NLRP3 pathway to alleviate DSS-induced ulcerative colitis.This study provides evidence for the potential of BCFAs as bioactive fatty acids in food products and to ameliorate ulcerative colitis development in mice.
文摘The search for functional foods with health benefits has increased,and yogurt represents one of these products due to their properties,such as,source of probiotics that favour the gastrointestinal system,contains vitamins,minerals and improves the action of enzymes.Present work investigated bromatological,microbiological,sensorial properties and shelf-life of different yogurt goat milk formulations with Aloe vera and natural sweeteners.The goat yogurt with 99.40%A.vera pulp and 0.60%S.rebaudiana presented the best nutritional composition,being suitable for human consumption representing an innovative product with a great functional potential.The synergy between the ingredients used in the yogurt processing resulted in an innovative product to the market.Goat milk has a lower cost per liter in comparison with cow milk,Aloe vera is accessible due to its fast-vegetative propagation,Stevia Rebaudiana has a great popularity for being a natural sweetener with no calories,and all these products are produced in México.
文摘Lactic acid bacteria (LAB) is widely used as culture starters in dairy fermentation. The aim of this study was to investigate the quality of fermented goat milk and cow milk, as well as the viability of LAB in the same products. Fermentations were performed with pasteurized goat milk or cow milk added with skim milk (18% of solids) using three separately different starters; yoghurt starter (a combination of Streptococcus thermophilus FNCC-0040 and Lactobacillus bulgaricus FNCC-0041), single starter of Lactobacillus acidophilus FNCC-0029 and Lactobacillus casei FNCC-0051. The parameters observed were pH, acidity, nutritional quality including protein, fat and lactose content and product's viscosity. Acidity, pH and viability of LAB were also monitored during storage at refrigerated temperature (4 ℃) for 28 days. Results show that the different LAB starters did not affect the pH, acidity, lactose and protein content. Differences on LAB starters affected fat content and viscosity. The highest score of viscosity (30.00 Pa.s ± 7.02 Pa.s) was observed on products fermented by yoghurt starters, followed by products obtained using starter of L. acidophilus (17.7 ±11.4) and L. casei (8.62 ±0.35). Protein content, acidity, pH and viscosity were not significantly different between products obtained from goat milk and cow milk. Fat content in fermented goat milk was higher (5.03% ±0.62%) than in fermented cow milk (3.52% ±0.37%), however, lactose content was higher in fermented cow milk (5.16% ±0.40%) than in fermented goat milk (4.53% ±0.35%). Total LAB concentration in fermented cow milk during storage was 8.03± 0.52 logt0 cfu/mL, while in fermented goat milk was 7.81 loglo cfu/mL ± 0.67 loglo cfu/mL. There was a 10.83% decrease in LAB viability in fermented cow milk and 11.40% in fermented goat milk after 28 days of storage. In conclusion, quality of fermented milk is affected by the starters applied, raw milk source and storage period.
文摘[Objectives]To amplify and identify the specific gene fragments of cattle and sheep by real-time fluorescence-based PCR,and quickly and accurately identify the adulteration problem of goat milk powder according to the differences of mitochondrial genes among different species.[Methods]The specificity,limit of detection and repeatability test were carried out by isolating somatic cells,extracting template DNA and determining the reaction conditions of real-time fluorescence-based PCR.[Results]The real-time fluorescence-based PCR method could be used to identify the bovine and ovine-derived materials of milk powder with high specificity,high sensitivity and good repeatability,and the limit of detection of milk components in goat milk powder could reach 0.01%.[Conclusions]The real-time fluorescence-based PCR method can be used to quickly and accurately detect the milk components in goat milk powder,and provide some technical support for the adulteration detection of dairy industry.
文摘A cross-sectional study was carried out to assess handling and hygienic production practices of goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 120 households were purposively selected for this study using a stratified sampling technique. The data were collected through the questionnaire, field observations, key informants interview and focus group discussions. The study showed that majority of the sampled households were illiterate. The goats were kept in an open kraal made of thorny acacia trees on an earthen floor that had no roof. The goats were milked inside these open kraals, and were sometimes contaminated with muck and animal dung mainly the rainy season which could raise the possibility of milk contamination & spoilage. Moreover, traditional hand milking was the only milking method and majority of the respondents didn’t wash their hands and the udder of the animal before milking, indicating low community awareness and knowledge of sanitary milk production procedures. Plastic equipment which is difficult to clean and can increase milk contamination and spoilage was used. About 43.3% of the pastoralists and 76.67% of the agro-pastoralists were cleaning milk vessels regularly. The most often used plant species for smoking milk handling equipment in the study area to extend shelf life and add flavor & aroma were Acacia ethaica, Blanites galabra, and Solanum Carense. The main constraints to hygienic goat milk in the area were identified to be poor barn hygiene, poor production procedures, disease, source of washing water and lack of extension services. In general, it can be concluded that handling and hygienic production practices of goat milk used in the study area were unsanitary, which may have been primarily caused by the community’s lack of awareness & understanding as well as a lack of supporting infrastructures. Therefore, the concerned bodies should place a high priority on the improvement of hygienic practices by carrying out various relevant development interventions, such as raising milk producers’ awareness, improving the health of goats, and providing the necessities for milk handling.
文摘A cross-sectional study was carried out to evaluate microbiological quality of raw goat milk in Degahbur district of Jarar zone, Somali Regional State, Ethiopia. A total of 40 pooled raw goat milk samples (each with a volume of 450 mL) were collected from the udders and milk handling equipment of targeted goat milk producers in the study area. The milk samples were subjected to laboratory analysis to evaluate total bacterial count (TBC) and total coliform count (TCC) in order to determine the microbiological quality of the raw goat milk in the study area. The study showed that the mean total bacterial count (TBC) and total coliform count (TCC) for raw milk samples collected from the udder were 4.92 ± 0.23 and 2.68 ± 0.36 log<sub>10</sub> cfu·mL<sup>-1</sup>, respectively. The mean counts for samples collected from milk equipment were 5.61 ± 0.32 and 3.93 ± 0.21 log<sub>10</sub> cfu·mL<sup>-1</sup> for TBC and TCC, respectively. The values for the samples collected from pastoral production system were 5.63 ± 0.13 and 4.02 ± 0.20 log<sub>10</sub> cfu·mL<sup>-1</sup> for TBC and TCC, respectively. The average means of TBC and TCC for samples collected from the agro-pastoral production system were 4.9 ± 0.41 and 2.59 ± 0.37 log<sub>10</sub> cfu·mL<sup>-1</sup>, respectively. Significant difference (P 0.05) in mean TBC and TCC was observed between milk samples collected from pastoral and agro-pastoral production systems as well as milk samples collected from udders and milk handling equipment of the producers. It could be concluded that both TBC & TCC of goat milk samples collected from the udder as well as from the milk handling equipment of producers exceeded the acceptable limits. This indicated that production practices performed during milk production and postharvest handling in the study area were unhygienic. Therefore, hygienic and proper milk production procedures should be followed to improve the quality of goat milk for its intended use in the study area.
文摘Goat milk ice cream was made with various sources of fat ingredients such as cream, soybean oil, rice bran oil and butter with the purpose of seeking the fat ingredient source instead of fat source from cow origin. The physical properties and the sensory evaluation of ice cream were then investigated. The firmness of goat milk ice cream mixed with rice bran oil, butter and cream were not significantly different before aging at 4 ℃ for 8 h. All of them gave the overrun between 51%-63% and the one with butter was the highest. The meltdown rate of all types of fat ingredients are not significantly different, being in the range of 0.86-0.88 g/min. According to sensory evaluation, the cow milk ice cream with cream was mostly accepted in all attributes such as appearance, smoothness, whiteness, melting in mouth and odor while the goat milk with cream and butter are the second and third. Nevertheless, the goat milk ice cream with soybean oil and rice bran oil were moderately accepted in overall preferences.
文摘The proteins coming from the milk whey have numerous functional properties. Among the proteins with high bioactivity, α-lactoalbumin (α-La) and β-lactoglobulin (β-Lg) are present in large quantities in the milk whey. In the separation process of proteins, it is important to choose techniques which besides ensuring purity and high yield will not affect the molecule biological activity. The aqueous two-phase systems (ATS) have been utilized with success in the partition of these proteins, however, the studies were performed using protein in its pure form. Studies using milk whey in-nature and goat milk whey have not been found yet. In this context, the objective of this study was to evaluate the liquid liquid equilibrium of aqueous two-phase systems (ATS) in the partition of α-La and β-Lg from goat milk whey in-nature. Equilibrium data were performed considering ATS comprised of polyethylene glycol, potassium phosphate and water at 25°C and pH 7.0. The influence of the polymer molecular weight and amount of goat milk whey in-nature on the partition coefficient of these proteins were assessed. The partition coefficient, selectivity, process yield and purity of α-lactoalbumin and β-lactoglobulin proteins were determined. The results showed that the separation technique by aqueous biphasic systems is applicable indicating high efficiency in the whey proteins separation process.
文摘Concentrations of 20 different minerals in commercial goat milk yogurt (CGY) and its cow milk yogurt (CCY) counterpart were evaluated in reference to goat milk yogurt manufactured from Fort Valley State University (FVGY), Fort Valley, GA, USA. Three different lots of CGY and CCY each were purchased from local retail stores at Warner Robins, GA, and 3 batches of FVGY were made using goat milk from the University milking herd. All 3 types of experimental yogurts were stored at 4°C refrigerator for 4 weeks. Twenty major and trace minerals were analyzed by an Inductively Coupled Plasma Optical Emissions Spectrometer (Thermo Jarrel Ash Enviro 36, Worchester, MA), using argon as the carrier gas and the EPA method 6010. Total solids (TS) content (%) of FVGY, CGY and CCY products were 11.03, 13.1 and 11.3, respectively, indicating CGY had higher TS than the CCY and FVGY yogurt. Respective mean mineral concentrations (ppm, wet basis) of FVGY, CGY and CCY were: Ca 1057, 1162, 1160;P 838, 974, 929;K 1327, 1717, 1208;Mg 102, 133, 113;Na 545, 449, 475;Fe 4.28, 3.33, 2.11;Mn 0.24, 0.19, 0.13;Cu 10.5, 9.85, 7.22;Zn 17.5, 11.7, 11.8. Levels of all macro minerals except potassium were higher in commercial goat and cow yogurts than FVGY, which may be due to the higher TS contents. FVGY had higher Fe, Mn, Cu and Zn than both commercial products. The heavy metal (Pb, Cd and Ni) contents (ppm) appeared to be normal range, while Al contents of FVGY, CGY and CCY were 11.9, 8.66 and 7.65, respectively, which were higher than those of Pb, Cd and Ni. Both commercial products contained higher major mineral contents than the university yogurt, which might be attributable to the differences in diet, breed, and stage of lactation of milking animals, as well as the tapioca additive used in the commercial products.
文摘Effects of frozen-storage on fatty acids profiles and basic nutrient contents of two types of low-fat caprine milk ice creams were investigated during 0, 2, 4, 8 weeks of storage at -18°C. Two types of the experimental low-fat soft-serve goat ice creams were manufactured using whole (full-fat) milk and 2% fat goat milk with addition of commercial powdered vanilla flavor pre-mix containing 0.25% fat (Alpha Freeze, D466-A9047, Tampa, FL, USA). Fatty acid concentrations were quantified using a Thermo Electronic gas chromatography (GC)-MS (Model TRACE GC Ultra, Austin, TX, USA) equiped with an automatic sampler (Model AS-3000, Thermo Electronic Co.). The results showed that fat content was the only basic nutrient component exhibited the difference between the two types of ice creams, while no other components have shown differences between the two low-fat ice creams during the storage periods. The level of lauric acid (C12:0) was the highest among all 16 fatty acids, followed by palmitic (C16:0), linoleic (C18:1), and myristic acid (C14:0). The high levels of the medium chain fatty acids (C12:0 and C14:0) might have been derived from the goat milk as well as the palm oil asa part of the ingredients in the commercial ice cream premix. Among long chain fatty acids, palmitic acid (C16:0) was the highest, followed by oleic acid (C18:1) and stearic acid (C18:0). All of the long chain fatty acids contents were significantly higher (P < 0.05 or 0.01) in whole milk ice cream than those in 2% fat ice cream, except for the C22:0 and C24:00 acids. It was concluded that mean levels of the individual fatty acids in the caprine ice creams were significantly influenced by the types of milk fat used in the ice creams, but not by storage periods and storage × fat type interaction effects.
文摘The study of the triacylglycerols (TAG) by gas chromatography (GC) using capillary columns is an efficient technique for the determination of some characteristics of quality of fats and oils. The objective of the present study was to determine by GC the content of TAG present in fat of cow and goat milk produced in four zones of Mexico. According to criteria established in Mexican Standardization, 25 samples were obtained of 1 L of ultra-pasteurized cow milk (UHT) and 27 and 48 of raw cow and goat milk, respectively. The fat was extracted from all of the milk samples by detergent solution, and was stored at –20℃ until its analysis. The chromatographic conditions made it possible to identify and quantify TAG of 28 to 54 numbers of carbons, which were analyzed under descriptive and inferential statistical techniques. For the cow milk fat, the statistical analyses indicated significant difference (p < 0.05) in the TAG C34, C50 and C52, and for the goat milk fat in the TAG of C36 to C52. No equality of means was found among the TAG of the cow and goat milk fat. This study offers an advance in the characterization of the TAG present in the cow and goat milk fat produced in Mexico.
文摘Differences in free fatty acid (FFA) compositions between low-fat (LF) and full-fat (FF: whole milk) goat cheeses were evaluated during 3 months at 4oC refrigeration. The two types of cheeses were manufactured using a bulk milk from the mixed herd of Saanen, Alpine, and Nubian goat breeds. LF cheeses were made using LF milk after cream separation. FFAs of all cheeses were extracted in diisoprophyl ether using polypropylene chromatography column, and FFA concentrations were quantified using a gas chromatograph equipped with a fused silica capillary column. Moisture, fat, protein contents (%) and pH of fresh LF and FF cheeses were: 55.1, 52.3;1.30, 25.6;35.7, 22.5;5.40, 5.42, respectively. The FFA contents (mg/g cheese) of fresh FF and LF cheeses prior to storage treatments for C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C16:0, C18:0, C18:1, and C18:2 were: 0.020, 0.072;0.070, 0.035;0.061, 0.055;0.181, 0.167;0.073, 0.047;0.174, 0.112;0.579, 0.152;0.308, 0.202;0.521, 0.174;and 0.057, 0.026, respectively. The respective FFA to total fatty acid ratios for 0, 1 and 3 months aged FF and LF cheeses were 8.44, 12.4;6.31, 16.91;12.03, 14.19. The LF cheeses generated more FFA than FF cheeses, while actual FFA content in FF cheese was significantly higher than in LF cheese. The FFA contents of LF cheese at 0, 1 and 3 months storage were 48.0, 96.8 and 36.4% of those of FF cheese, respectively. It was concluded LF cheese generated higher amount of FFA than FF cheese, although total FFA content was significantly (P<0.05) lower in LF cheese than in FF cheese.
文摘Camels’ milk (CM) and goats’ milk (GM) are rich in nutrients and vitamins necessary for the health of humans and have therapeutic properties as they are rich in antioxidants and have a protective role against free radicals that </span><span style="font-family:Verdana;">have harmful effects on human health. Date palm (DP), camels’ milk and </span><span style="font-family:Verdana;">goats’ milk have been reported to be used for the prevention and treatment of vari</span><span style="font-family:Verdana;">ous diseases in Arab countries. This study was designed to mix date palm</span><span style="font-family:Verdana;"> with camels’ milk and goats’. Eight formulations of both camels’ milk and goats’ were made from different percentages of date palm. These formulations were added at ratios of 0 (control), 10%, 20% and 30% (w/v) to camels’ milk and goats’ and the effect of this date palm on the composition and texture properties of the fermented obtained products were followed. It has been found that pH, protein, fat decreased and total solid, carbohydrate, ash, viscosity, vitamins, minerals and antioxidants increased with the increase of the added percentage of date palm compared to control. Microbial counts of the fermented camels’ milk (FCM) and goats’ milk (FGM) increased significantly (P < 0.05) with the addition of different formulations and during storage. Also, fermented camels’ milk (FCM) and fermented goats’ milk (FGM) fortified with different ratios date palm (DP) concentration resulted in good properties and higher acceptable sensory values (at a rate of 10% - 20%) in fresh and till the end of storage periods. The addition of the date palm to all treatments </span><span style="font-family:Verdana;">improved the composition, viscosity, microbiological quality of fermented</span> <span style="font-family:Verdana;">camels’ and goats’ milk with nutritional functional values and acceptable</span><span style="font-family:Verdana;"> sensory attributes.
基金Part of the experiment was financed by the project of Ministry of Agriculture of China (nyhyzx07-036,nycytx-02-04)partly by the project of Youth Fund financed by Shandong Agriculture University, China
文摘Four non-pregnant multiparous lactating goats were used in a 4 × 4 latin square experiment in the present study. The four treatments were abomasal infusion of 0, 50, 100, and 150 g d^-1 glucose. The results showed that graded glucose infusion increased milk yield (P 〈 0.01). The highest milk yield was observed when 50 g d^-1 glucose was infused. An infusion of glucose at 100 or 150 g d^-1 failed to increase milk yield further and milk yield of the 100 g d ^-1 glucose infusion treatment was even significantly lower than that of the 50 g d^-1 treatment (P 〈 0.01). Though milk fat content was gradually decreased by graded glucose infusions and milk fat yield of the 100 and 150 g d 1 treatments were lower than that of the control (P 〈 0.01); milk fat yield of the 50 g d i treatment was not depressed and was higher than that of the control (P 〈 0.01). Graded glucose infusion did not change the contents of milk protein and non-fatty solids. Yields of milk protein (P 〈 0.05), lactose (P 〈 0.01), non-fat solids (P 〈 0.01), and lactose content (P 〈 0.01) of the 50 g d^-1 treatment were higher than those of the control but had no difference among the other three treatments. Contents of those de novo synthesized fatty acids in milk fat remained unchanged or increased and those preformed fatty acids remained unchanged or decreased by graded glucose infusion. Glucose infusion decreased the total yields of C16 + C16:1 and 〉 C16 fatty acids and had no influence on the yield of C4-C14:1 fatty acids (P 〈 0.05). Results of the present study implied that increased glucose supply had positive effects on the production of milk, milk protein, milk fat, and lactose only when glucose was a limiting factor for milk synthesis. Excessive glucose supply had no further beneficial effects and might depress milk fat synthesis.
文摘To research the relation among the erythrocytic membrane.liquidity and the contents of MDA, the activity of SOD in serum of the milk goat with fluorosis. An animal model with fluorosis was constructed, and the fluorescent probe technique of DPH was used to measue the erythrocytic membrane liquidity. At the same time, the contents of MDA and the activity of SOD in serum were measured. The results showed that the erythrocytic membrane liquidity in the control group and flurosis group were 5.6742 ± 0.4417 and 3.7248 ± 0.4521 (P 〈0.01) respectively, the contents of MDA in serum were 2.0408 ± 0.198 and 4.494± 0.438 (P 〈0.01) respectively, the activities of SOD were 175.638 ± 22.201 and 113.714 ± 34.258 (P 〈0.01) respectively. The correlation analysis indicated that the relation between the activity of SOD and the liquidity of erythrocytic membrane was positive correlation ( r= 0.7321, P 〈0.05), whereas the relation between the contents of MDA and the liquidity of erythrocytic membrane was negative correlation (r = -0.6438, P 〈0.01). The erythrocytic membrane liquidity decreased in milk goat with fluorosis, which played a role in the occurrence and development of the fluorosis. There was correlation among the erythrocytic membrane liquidity and the contents of MDA, the activity of SOD.
基金supported by the National Nature Science Foundation of China(project no.31572433)the National Key R&D Program(2016YFD0501203)+1 种基金the Program for New Century Excellent Talents in University(NCET-13-0862)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet(35% concentrate, n = 5, LC) and there were two high-concentrate treatments(65% concentrate, HC), one fed a high concentrate diet for a long period(19 wks, n = 7, HL); one fed a high concentrate diet for a short period of time(4 wk, n = 5, HS). Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results: Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet(P 〈 0.01), while the percentage of milk fat was lower in the HL(P 〈 0.05) but not in the HS group. The total amount of saturated fatty acids(SFA) in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids(UFA) and monounsaturated fatty acids(MUFA) were markedly decreased in the HL group compared with the LC group(P 〈 0.05). Among these fatty acids, the concentrations of C15:0(P 〈 0.01), C17:0(P 〈 0.01), C17:1(P 〈 0.01), C18:1 n-9 c(P 〈 0.05), C18:3 n-3 r(P 〈 0.01) and C20:0(P 〈 0.01) were markedly lower in the HL group, and the concentrations of C20:0(P 〈 0.05) and C18:3 n-3 r(P 〈 0.01) were lower in the HS group compared with the LC group. However, the concentrations of C18:2 n-6 c(P 〈 0.05) and C20:4 n-6(P 〈 0.05) in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 & 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group(P 〈 0.05), and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group(P 〈 0.05). In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group(P 〈 0.05). The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group(P 〈 0.05).Conclusions: Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods.
基金funded by the National Natural Science Foundation of China (31172184)the Young New Star Project on Science & Technology of Shaanxi Province, China(2011kjxx64)+2 种基金the Natural Science Foundation of Shaanxi Province of China (2011JQ3009)the Young Topnotch Researcher Support Project of Northwest A&F University,China (QNGG-2009-007)the Special Fund for Basic Scientific Research and Operation Expenses in Sci-Tech Innovation of Northwest A&F University, China(QN2011102)
文摘Paired-like homeodomain transcription factor 1 (PITX1) plays an important role in pituitary development by indirectly regulating the expression of the GH and PRL genes, and therefore PITX1 gene is regarded as a potential candidate gene for building the relationship between the gene polymorphism and milk traits. The aim of this study was to explore the novel genetic variant in PITX1 gene and its effect on milk performance in dairy goats. Herein, a novel genetic variation (NW_00314033: g.201GA or IVS1+41GA) located at nt41 position of the first intron of the goat PITX1 gene was reported at the P1 locus, which can be genotyped by the Msp I PCR-RFLP. In the Msp I PCR-RFLP analyis, the GG variant was a major genotype, and the A variant was a minor allele in Guanzhong dairy goats which was at Hardy-Weinberg disequilibrium (chi-square χ2=140, P0.01). The establishment of associations between different genotypes and milk performance was performed in the analyzed population. A total of three significant associations of the polymorphism with average milk fat content (%) (P=0.045), morning milk fat content (%) (P=0.049), and afternoon milk fat content (%) (P=0.050), were found, respectively. A significant relationship between the polymorphism and average total solid content (P=0.029) was also detected. This novel single nucleotide polymorphism (SNP) extended the spectrum of genetic variation of the goat PITX1 gene, and its significant association with milk performance would benefit from the application of DNA markers related to improving milk performance through marker-assisted selection (MAS) in dairy goats.
文摘Lactic acid bacteria (LAB) were isolated from goat's milk in different north west region of Algeria. A total of 233 isolates were identified as LAB. However, only 11 strains showed excellent inhibition zones on agar when Salmonella lyphimorium ATCC 13311 was used as an indicator for preliminary detection of antagonistic activity. After elimination of inhibition due to acid and H202, Staphylococcus aureus ATCC 25923 was used for secondary screening for antagonistic activity of these 11 strains. It was found that only 9 strains exhibited a good inhibition zones on agar, and all of them could inhibit E. coli ATCC 25921 and Pseudomonas aeruginosa ATCC 27853 as the third and the forth indicators respectively. Lactococcus lactis subsp, cremoris, Lactobacillus casei subsp, casei, Lactobacillus casei subsp, rhamnosus, Streptococcus salivarius subsp, thermophilus and Lactococcus lactis biovar. diacetylactis were the strains that have a good antibacterial activity, survive in the gastrointestinal conditions and were sensible to the majority of the antibiotics. All isolated strains tolerate pH = 2 and high bile salt concentration.
文摘Twenty-two lactic acid bacteria (LAB) strains isolated from Argentinean goat dairy products were evaluated for its biochemical properties and esterase activities relevant to flavor development. Streptococcus thermophilus (UNSE314), Lactobacillus (L.) delbrueckii subsp, bulgaricus (UNSE309), L. rhamnosus (UNSE308), L. plantarum (UNSE287, UNSE316, UNSE317) and Pediococcus pentosaceus (UNSE315) strains presented high acidifying activity. All strains tested metabolized citrate and produced diacetyl-acetoin in goat milk. Based on these results, 10 strains with the best performance in diverse technological properties were selected to determine esterolytic activity. In all evaluated strains, esterase specific activity (ESA) was detected on ct-naphthyl (ct-NA) acetate and 13-naphthyl ([3-NA) acetate, propionate, eaprylate and ct-NA butyrate. No activity was detected on [3-NA laurate. The highest values were detected when using a-NA instead of fI-NA derivatives as substrate. In Pediocoecus strains, wide variability in ESA were observed, which were species- and strain-specific. These results allow us to select strains with biochemical properties and esterase activities to design starter and adjunct cultures that contribute to flavor development during cheese ripening, thus preserving the typical organoleptic characteristics of Argentinean goat cheeses.
文摘The experiment was conducted to investigate the effect of transfer of PUFA protected and carnitin precursor on the ration of chemical composition of milk dairy goat. In total, 10 female dairy goats of 2 - 4 years old Peranakan Etawah (PE) with body weight of 25 - 45 kg were used in this experiment. The feed material included a basal diet (control) based on yellow corn, rice bran, soya bean meal, coconut meal, tuna fish oil and lemuru fish oil. The method of the research was experimental in vivo using Randomized Completely Block Design (RCBD). There were 5 treatments in each experiment and 2 replications. The treatment consisted of P0 = control ration, P1 = P0 + 200 ppm L-carnitine on the ration, P2 = P1 + soya bean oil, P3 = P1 + protected tuna fish oil 5 ml or equal with 4% in the ration, and P4 = P1 + protected lemuru fish oil 5 ml or equal with 4% in the ration. The measured variable is chemical composition of milk dairy goat. The results of variance analysis showed that the effect of transfer of PUFA fatty acid in the rations contained 200 ppm L-carnitine significantly