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Repeated inoculation with rumen fluid accelerates the rumen bacterial transition with no benefit on production performance in postpartum Holstein dairy cows
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作者 Fanlin Kong Feiran Wang +3 位作者 Yijia Zhang Shuo Wang Wei Wang Shengli Li 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期795-811,共17页
Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal mi... Background The dairy cow’s postpartum period is characterized by dramatic physiological changes,therefore imposing severe challenges on the animal for maintaining health and milk output.The dynamics of the ruminal microbiota are also tremendous and may play a crucial role in lactation launch.We aim to investigate the potential benefits of early microbial intervention by fresh rumen microbiota transplantation(RMT)and sterile RMT in postpartum dairy cows.Twelve fistulated peak-lactation dairy cows were selected to be the donors for rumen fluid collection.Thirty postpartum cows were divided into 3 groups as the transplantation receptors respectively receiving 10 L fresh rumen fluid(FR),10 L sterile rumen fluid(SR),or 10 L saline(CON)during 3 d after calving.Results Production performance,plasma indices,plasma lipidome,ruminal microbiome,and liver transcriptome were recorded.After fresh and sterile RMT,we found that the molar proportion of propionic acid was increased on d 7 in the FR and SR groups and the bacterial composition was also significantly changed when compared with the CON group.A similarity analysis showed that the similarities between the CON group and FR or SR group on d 7 were 48.40%or 47.85%,whereas the similarities between microbiota on d 7 and 21 in the FR and SR groups were 68.34%or 66.85%.Dry matter intake and feed efficiency were not affected by treatments.Plasmaβ-hydroxybutyrate concentration in the FR group was decreased and significantly different lipids mainly included phosphatidylcholine and lysophosphatidylcholine containing polyunsaturated fatty acids.Hepatic transcriptomics analysis indicated acutephase response pathways were upregulated in the SR group.Conclusions Our study suggests that RMT can shorten the transition process of the ruminal microbiota of postpartum dairy cows with no benefit on dry matter intake or feed efficiency.Inoculation with rumen fluid may not be a useful approach to promote the recovery of postpartum dairy cows. 展开更多
关键词 Dairy cow LIPIDOMICS Liver Rumen microbiota transplantation Transition period
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Multi‑omics reveals that the host‑microbiome metabolism crosstalk of differential rumen bacterial enterotypes can regulate the milk protein synthesis of dairy cows 被引量:1
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作者 Chenguang Zhang Mengya Wang +8 位作者 Huifeng Liu Xingwei Jiang Xiaodong Chen Tao Liu Qingyan Yin Yue Wang Lu Deng Junhu Yao Shengru Wu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2496-2513,共18页
Background Dairy cows’lactation performance is the outcome of the crosstalk between ruminal microbial metabo-lism and host metabolism.However,it is still unclear to what extent the rumen microbiome and its metabolite... Background Dairy cows’lactation performance is the outcome of the crosstalk between ruminal microbial metabo-lism and host metabolism.However,it is still unclear to what extent the rumen microbiome and its metabolites,as well as the host metabolism,contribute to regulating the milk protein yield(MPY).Methods The rumen fluid,serum and milk of 12 Holstein cows with the same diet(45%coarseness ratio),parity(2–3 fetuses)and lactation days(120–150 d)were used for the microbiome and metabolome analysis.Rumen metabolism(rumen metabolome)and host metabolism(blood and milk metabolome)were connected using a weighted gene co-expression network(WGCNA)and the structural equation model(SEM)analyses.Results Two different ruminal enterotypes,with abundant Prevotella and Ruminococcus,were identified as type1 and type2.Of these,a higher MPY was found in cows with ruminal type2.Interestingly,[Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae(the differential bacteria)were the hub genera of the network.In addition,differential ruminal,serum and milk metabolome between enterotypes were identified,where the cows with type2 had higher L-tyrosine of rumen,ornithine and L-tryptophan of serum,and tetrahydroneopterin,palmitoyl-L-carnitine,S-lactoylglutathione of milk,which could provide more energy and substrate for MPY.Further,based on the identi-fied modules of ruminal microbiome,as well as ruminal serum and milk metabolome using WGCNA,the SEM analysis indicated that the key ruminal microbial module1,which contains the hub genera of the network([Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae)and high abundance of bacteria(Prevotella and Ruminococcus),could regulate the MPY by module7 of rumen,module2 of blood,and module7 of milk,which contained L-tyrosine and L-tryptophan.Therefore,in order to more clearly reveal the process of rumen bacterial regulation of MPY,we established the path of SEM based on the L-tyrosine,L-tryptophan and related components.The SEM based on the metabolites suggested that[Ruminococcus]gauvreauii group could inhibit the energy supply of serum tryptophan to MPY by milk S-lactoylglutathione,which could enhance pyruvate metabolism.Norank_f_Ruminococcaceae could increase the ruminal L-tyrosine,which could provide the substrate for MPY.Conclusion Our results indicated that the represented enterotype genera of Prevotella and Ruminococcus,and the hub genera of[Ruminococcus]gauvreauii group and norank_f_Ruminococcaceae could regulate milk protein synthesis by affecting the ruminal L-tyrosine and L-tryptophan.Moreover,the combined analysis of enterotype,WGCNA and SEM could be used to connect rumen microbial metabolism with host metabolism,which provides a fundamental understanding of the crosstalk between host and microorganisms in regulating the synthesis of milk composition. 展开更多
关键词 Dairy cows Microbial and host metabolome Milk protein Ruminal microbiota enterotype Structural equation model Weighted gene co-expression network
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基于Cow-DETR与深度图像的非接触式奶牛体质量评估
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作者 沈维政 张哲 +3 位作者 戴百生 王鑫杰 赵凯旋 李洋 《农业机械学报》 EI CAS CSCD 北大核心 2023年第8期277-285,319,共10页
针对当前牧场奶牛体质量(体重)称量效率低,人工参与容易引发奶牛应激等问题,提出了一种基于改进DETR(Detection transformer)网络的端到端式奶牛体质量评估方法(Cow-DETR),实现利用奶牛背部深度图像进行非接触式奶牛体质量评估。首先设... 针对当前牧场奶牛体质量(体重)称量效率低,人工参与容易引发奶牛应激等问题,提出了一种基于改进DETR(Detection transformer)网络的端到端式奶牛体质量评估方法(Cow-DETR),实现利用奶牛背部深度图像进行非接触式奶牛体质量评估。首先设计并搭建实验数据采集装置,利用Intel RealSense D435深度相机和体重秤采集奶牛背部深度图像和体质量数据;然后,通过边缘平滑滤波器和孔洞填充滤波器对深度图像进行补全处理,减少深度数据缺失对体质量评估的影响;最后,以DETR网络为基础建立奶牛体质量评估模型,通过在预测模块中添加含有交替全连接层的体质量预测单元,提升奶牛体质量相关的特征信息提取能力,实现端到端式奶牛背部定位的同时进行奶牛体质量非接触式评估。结果表明,本文方法可以实现较高精度的奶牛体质量评估,通过5倍交叉验证,在含有139头奶牛数据的数据集中,平均绝对误差不超过17.21 kg,平均相对误差不超过3.71%,单幅图像平均识别时间为0.026 s。通过与现有体质量评估方法相对比,本文方法比其他6种方法在更多的奶牛头数的数据集中取得了更低的平均绝对误差和平均相对误差,同时本文方法对奶牛站立姿势要求较低,更符合牧场实际生产需要,为奶牛体质量评估提供了新的解决思路。 展开更多
关键词 奶牛 体质量评估 目标检测 深度图像 深度学习
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Effects of omega-3 supplementation on components of the endocannabinoid system and metabolic and inflammatory responses in adipose and liver of peripartum dairy cows
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作者 Gitit Kra Jayasimha Rayalu Daddam +6 位作者 Uzi Moallem Hadar Kamer Radka Kočvarova Alina Nemirovski GAndres Contreras Joseph Tam Maya Zachut 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期378-389,共12页
Background:Dietary supplementation of omega-3 fatty acids can reduce the activation of the endocannabinoid system(ECS)by decreasing the availability of arachidonic acid,thus lowering endocannabinoids(e CBs)levels.The ... Background:Dietary supplementation of omega-3 fatty acids can reduce the activation of the endocannabinoid system(ECS)by decreasing the availability of arachidonic acid,thus lowering endocannabinoids(e CBs)levels.The ECS is a modulator of energy metabolism,stress response and inflammation in mammals,yet there is little information on the roles of the ECS in transition dairy cows.During the periparturient period,the adipose tissue and liver are the main metabolic organs that participate in the adaptations of dairy cows to onset of lactation;however,exceeded adipose tissue lipolysis and accumulation of lipids in the liver have adverse effects on cows'physiology.Here we aimed to examine whether omega-3 supplementation during the transition period will modulate ECS activation and affect metabolic and inflammatory indices in postpartum dairy cows,by supplementing twenty-eight transition Holstein dairy cows with either saturated fat(CTL)or encapsulated flaxseed oil(FLX).Components of the ECS,metabolic and inflammatory markers were measured in blood,liver,and subcutaneous adipose tissue.Results:FLX supplementation reduced feed intake by 8.1%(P<0.01)and reduced plasma levels of arachidonic acid(by 44.2%;P=0.02)and anandamide(by 49.7%;P=0.03)postpartum compared to CTL.The m RNA transcription levels of the cannabinoid receptor 1(CNR1/CB1)tended to be lower(2.5 folds)in white blood cells of FLX than in CTL(P=0.10),and protein abundance of ECS enzyme monoacylglycerol lipase was higher in peripheral blood mononuclear cells of FLX than in CTL(P=0.04).In adipose tissue,palmitoylethanolamide levels were lower in FLX than in CTL(by 61.5%;P=0.02),relative m RNA transcription of lipogenic genes were higher,and the protein abundance of cannabinoid receptor 2(P=0.08)and monoacylglycerol lipase(P=0.10)tended to be higher in FLX compared to CTL.Hepatic 2-arachidonoylglycerol tended to be higher(by 73.1%;P=0.07),and interlukin-6 m RNA transcription level was 1.5 folds lower in liver of FLX than in CTL(P=0.03).Conclusions:Nutritional supplementation of omega-3 fatty acids seems to partly modulate ECS activation,which could be related to lower feed intake.The altered ECS components in blood,adipose tissue and liver are associated with moderate modulations in lipid metabolism in the adipose and inflammation in liver of peripartum dairy cows. 展开更多
关键词 ADIPOSE Dairy cows Endocannabinoid system LIVER Omega-3
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Predicting nitrogen use efficiency,nitrogen loss and dry matter intake of individual dairy cows in late lactation by including mid‑infrared spectra of milk samples
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作者 Rui Shi Wenqi Lou +5 位作者 Bart Ducro Aart van der Linden Han A.Mulder Simon J.Oosting Shengli Li Yachun Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第3期1287-1299,共13页
Background Nitrate leaching to groundwater and surface water and ammonia volatilization from dairy farms have negative impacts on the environment.Meanwhile,the increasing demand for dairy products will result in more ... Background Nitrate leaching to groundwater and surface water and ammonia volatilization from dairy farms have negative impacts on the environment.Meanwhile,the increasing demand for dairy products will result in more pollution if N losses are not controlled.Therefore,a more efficient,and environmentally friendly production system is needed,in which nitrogen use efficiency(NUE)of dairy cows plays a key role.To genetically improve NUE,extensively recorded and cost-effective proxies are essential,which can be obtained by including mid-infrared(MIR)spectra of milk in prediction models for NUE.This study aimed to develop and validate the best prediction model of NUE,nitrogen loss(NL)and dry matter intake(DMI)for individual dairy cows in China.Results A total of 86 lactating Chinese Holstein cows were used in this study.After data editing,704 records were obtained for calibration and validation.Six prediction models with three different machine learning algorithms and three kinds of pre-processed MIR spectra were developed for each trait.Results showed that the coefficient of determination(R2)of the best model in within-herd validation was 0.66 for NUE,0.58 for NL and 0.63 for DMI.For external validation,reasonable prediction results were only observed for NUE,with R2 ranging from 0.58 to 0.63,while the R2 of the other two traits was below 0.50.The infrared waves from 973.54 to 988.46 cm−1 and daily milk yield were the most important variables for prediction.Conclusion The results showed that individual NUE can be predicted with a moderate accuracy in both within-herd and external validations.The model of NUE could be used for the datasets that are similar to the calibration dataset.The prediction models for NL and 3-day moving average of DMI(DMI_a)generated lower accuracies in within-herd validation.Results also indicated that information of MIR spectra variables increased the predictive ability of models.Additionally,pre-processed MIR spectra do not result in higher accuracy than original MIR spectra in the external validation.These models will be applied to large-scale data to further investigate the genetic architecture of N efficiency and further reduce the adverse impacts on the environment after more data is collected. 展开更多
关键词 Dairy cow Environment Mid-infrared spectra Nitrogen use efficiency Prediction
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Heat stress affects dairy cow health status through blood oxygen availability
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作者 Jia Zeng Jie Cai +3 位作者 Diming Wang Hongyun Liu Huizeng Sun Jianxin Liu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2663-2673,共11页
Background Rises in global warming and extreme weather occurrence make the risk of heat stress(HS)induced by high ambient temperatures more likely in high-yielding dairy cows,resulting in low milk quality and yield.In... Background Rises in global warming and extreme weather occurrence make the risk of heat stress(HS)induced by high ambient temperatures more likely in high-yielding dairy cows,resulting in low milk quality and yield.In ani-mals,oxygen is involved in many physiological and metabolic processes,but the effects of HS on oxygen metabolism remain unclear.Thus,the current study aimed to investigate how oxygen metabolism plays a role in health status of dairy cows by measuring the milk yield,milk composition,and blood biochemical variables of cows under different levels of HS:none(No-HS),mild(Mild-HS),and moderate HS(Mod-HS).Results The HS significantly increased rectal temperature(Ptreat<0.01)and respiration rate(Ptreat<0.01).Under Mod-HS,greater Na+(P<0.05)and lower total CO_(2),and pH(P<0.05)were observed relative to those under No-HS and Mild-HS.Oxygen concentrations in both coccygeal artery and mammary vein(Ptreat<0.01)were lower under Mod-HS than under No-HS.Coccygeal vein concentrations of heat shock protein 90(HSP90)(P<0.05)increased during Mod-HS compared with those in cows under No-HS.Malondialdehyde increased during Mod-HS,and glu-tathione peroxidase(P<0.01)increased during Mild-HS.Coccygeal vein concentrations of vascular endothelial growth factor(P<0.01),heme oxygenase-1(P<0.01),and hypoxia-inducible factor 1α(P<0.01)were greater in cows under Mod-HS than those under No-HS.Red blood cell count(P<0.01)and hemoglobin concentration(P<0.01)were lower in the coccygeal vein of dairy cows under Mild-and Mod-HS than those of cows under No-HS.Conclusions Exposure to HS negatively impacts the health status and lactation performance of dairy cows by limit-ing oxygen metabolism and transportation.However,the specific mechanism by which HS affects mammary function in cows remains unclear and requires further exploration. 展开更多
关键词 Dairy cow Health status Heat stress Lactation performance Oxygen metabolism
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Evaluation of Holstein cows with different tongue‑rolling frequencies:stress immunity,rumen environment and general behavioural activity
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作者 Fuyu Sun Xiaoyang Chen +2 位作者 Yongfeng Li Guangyong Zhao Xianhong Gu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2686-2700,共15页
Background The tongue-rolling behaviour of cows is regarded as an outward sign of stressed animals in a low welfare status.The primary aim of this observational study was to evaluate the association between the freque... Background The tongue-rolling behaviour of cows is regarded as an outward sign of stressed animals in a low welfare status.The primary aim of this observational study was to evaluate the association between the frequency of tongue-rolling behaviour and its physiological function.The secondary aim was to explore the relationship between general activities and the frequency of tongue-rolling behaviour of cows.A total of 126 scan sampling behavioural observations were collected over 7 d on 348 Holstein cows with the same lactation stage in the same barn.The tongue-rolling frequency was defined as the number of tongue-rolling observations as a percentage to the total observations per individual cow.According to their tongue-rolling frequency,the cows were grouped into the CON(no tongue-rolling),LT(frequency 1%),MT(frequency 5%),and HT(frequency 10%)groups.Six cows from each group were randomly selected for sampling.Serum samples,rumen fluid,milk yield,and background infor-mation were collected.The general behaviour data during 72 continuous hours of dairy cows,including eating time,rumination time,food time(eating time+rumination time),and lying time,were recorded by the collar sensor.Results Cortisol(P=0.012),γ-hydroxybutyric acid(P=0.008),epinephrine(P=0.030),and dopamine(P=0.047)levels were significantly higher in tongue-rolling groups than in the CON group.Cortisol levels and tongue-rolling frequency had a moderate positive correlation(linearly r=0.363).With the increase in tongue-rolling frequency,the rumen pH decreased first and then increased(P=0.013),comparing to the CON group.HT cows had significantly less food time than CON cows(P=0.035).The frequency of tongue-rolling had a moderate negative relationship with rumination time(r=-0.384)and food time(r=-0.492).Conclusions The tongue-rolling behaviour is considered as a passive coping mechanism,as the stress response in cows with high tongue-rolling frequency increased.Food intake and rumination activities were all closely related to the occurrence of tongue-rolling behaviour. 展开更多
关键词 General activity Holstein cow Rumen fermentation Stress immunity Tongue rolling
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Dietary supplementation with xylooligosaccharides and exogenous enzyme improves milk production,energy utilization efficiency and reduces enteric methane emissions of Jersey cows
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作者 Lifeng Dong Lei Zhao +5 位作者 Bowei Li Yanhua Gao Tianhai Yan Peter Lund Zhuofan Liu Qiyu Diao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2514-2524,共11页
Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to in... Background Sustainable strategies for enteric methane(CH_(4))mitigation of dairy cows have been extensively explored to improve production performance and alleviate environmental pressure.The present study aimed to investigate the effects of dietary xylooligosaccharides(XOS)and exogenous enzyme(EXE)supplementation on milk production,nutrient digestibility,enteric CH_(4) emissions,energy utilization efficiency of lactating Jersey dairy cows.Forty-eight lactating cows were randomly assigned to one of 4 treatments:(1)control diet(CON),(2)CON with 25 g/d XOS(XOS),(3)CON with 15 g/d EXE(EXE),and(4)CON with 25 g/d XOS and 15 g/d EXE(XOS+EXE).The 60-d experimental period consisted of a 14-d adaptation period and a 46-d sampling period.The enteric CO_(2)and CH_(4) emissions and O2 consumption were measured using two GreenFeed units,which were further used to determine the energy utilization efficiency of cows.Results Compared with CON,cows fed XOS,EXE or XOS+EXE significantly(P<0.05)increased milk yield,true protein and fat concentration,and energy-corrected milk yield(ECM)/DM intake,which could be reflected by the significant improvement(P<0.05)of dietary NDF and ADF digestibility.The results showed that dietary supplementation of XOS,EXE or XOS+EXE significantly(P<0.05)reduced CH_(4) emission,CH_(4)/milk yield,and CH_(4)/ECM.Furthermore,cows fed XOS demonstrated highest(P<0.05)metabolizable energy intake,milk energy output but lowest(P<0.05)of CH_(4) energy output and CH_(4) energy output as a proportion of gross energy intake compared with the remaining treatments.Conclusions Dietary supplementary of XOS,EXE or combination of XOS and EXE contributed to the improvement of lactation performance,nutrient digestibility,and energy utilization efficiency,as well as reduction of enteric CH_(4) emissions of lactating Jersey cows.This promising mitigation method may need further research to validate its long-term effect and mode of action for dairy cows. 展开更多
关键词 Energy utilization efficiency Enteric methane emissions Exogenous enzyme Jersey cows XYLOOLIGOSACCHARIDES
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The effect of ensiled paulownia leaves in a high-forage diet on ruminal fermentation,methane production,fatty acid composition,and milk production performance of dairy cows
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作者 Haihao Huang Dorota Lechniak +7 位作者 Malgorzata Szumacher‑Strabel Amlan Kumar Patra Martyna Kozłowska Pawel Kolodziejski Min Gao Sylwester Ślusarczyk Daniel Petrič Adam Cieslak 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第1期339-357,共19页
Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(... Background:The use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production.Paulownia leaves silage(PLS)was supplemented to dairy cows'diet and evaluated in vitro(Exp.1;Rusitec)and in vivo(Exp.2,cannulated lactating dairy cows and Exp.3,non-cannulated lactating dairy cows).The study investigated the PLS effect on ruminal fermentation,microbial populations,methane production and concentration,dry matter intake(DMI),and fatty acid(FA)proportions in ruminal fluid and milk.Results:Several variables of the ruminal fluid were changed in response to the inclusion of PLS.In Exp.1,the p H increased linearly and quadratically,whereas ammonia and total volatile fatty acid(VFA)concentrations increased linearly and cubically.A linear,quadratic,and cubical decrease in methane concentration was observed with increasing dose of the PLS.Exp.2 revealed an increase in ruminal p H and ammonia concentrations,but no changes in total VFA concentration.Inclusion of PLS increased ruminal propionate(at 3 h and 6 h after feeding),isovalerate,and valerate concentrations.Addition of PLS also affected several populations of the analyzed microorganisms.The abundances of protozoa and bacteria were increased,whereas the abundance of archaea were decreased by PLS.Methane production decreased by 11%and 14%in PLS-fed cows compared to the control in Exp.2 and 3,respectively.Exp.3 revealed a reduction in the milk protein and lactose yield in the PLS-fed cows,but no effect on DMI and energy corrected milk yield.Also,the PLS diet affected the ruminal biohydrogenation process with an increased proportions of C18:3 cis-9 cis-12 cis-15,conjugated linoleic acid,C18:1 trans-11 FA,polyunsaturated fatty acids(PUFA),and reduced n6/n3 ratio and saturated fatty acids(SFA)proportion in milk.The relative transcript abundances of the 5 of 6 analyzed genes regulating FA metabolism increased.Conclusions:The dietary PLS replacing the alfalfa silage at 60 g/kg diet can reduce the methane emission and improve milk quality with greater proportions of PUFA,including conjugated linoleic acid,and C18:1 trans-11 along with reduction of SFA. 展开更多
关键词 Dairy cow Fatty acid composition in milk Methane emission Paulownia leaves
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Assessment of the Effects of Supplemental Rumen Protected B Vitamins and Choline for Periparturient Cows: A Meta-Analysis of 28 Feeding Studies
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作者 Essi Evans Emilie Fontaine +1 位作者 Ousama AlZahal Chris Gwyn 《Open Journal of Animal Sciences》 CAS 2023年第1期151-165,共15页
There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to peripart... There are currently no prescribed requirements for B vitamins or choline for dairy cows during the transition period, but many recent studies have shown a variety of benefits from supplying these nutrients to periparturient cows. The purpose of this research effort was to determine the potential benefit of including a rumen protected blend composed of B vitamins (riboflavin, folic acid, vitamin B12) and choline (RPBlend, Jefo Nutrition Inc., St. Hyacinthe, QC, Canada) for dairy cows during the transition period, based on results from 28 on-farm feeding studies (USA-12, Mexico-7, Canada-4, Chile-3, Australia-1, Brazil-1) conducted between 2011 and 2018. All farms participated in monthly herd management record keeping systems and were selected to participate in studies due to their excellent management. Meta-analyses in which risk differences were determined were used to assess the effects of the supplemental RPBlend on health parameters and reproduction. The effect size was used as the determinant of the possible contribution of RPblend on the yields of milk, energy corrected milk (ECM), fat and protein yields during the first four weeks of lactation. Results showed that the inclusion of RPblend reduced (P < 0.05) involuntary culling and mastitis by cows during the first 30 days after calving. There was a tendency (P < 0.10) for reduced retained placenta and metritis. The meta-analyses revealed that the risk of the displaced abomasum and milk fever did not diminish (P > 0.10) with the inclusion of the BPBlend. The incidence rate of subclinical ketosis, determined as blood beta hydroxy butyric acid greater than 1.2 mM was lower (P (than those not supplemented. The proportion of cows confirmed pregnant by 100 days in milk was greater for cows given the BPBlend (P < 0.05). Milk yield and ECM were greater for cows receiving the RPBlend (1.13 and 0.93 kg/cow respectively, P < 0.05). There was no change in fat yield (P > 0.10) while the yield of milk protein was greater (P < 0.05) when the cows received the blend. These results suggest that the inclusion of rumen protected B vitamins and choline can assist cow health, reproduction and production at the start of lactation. 展开更多
关键词 Lactating Dairy cows Transition Period Rumen Protection B Vitamins CHOLINE
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Production of Biogas from Olive Mill Waste Waters Treated by Cow Manure
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作者 Fatma Laabidi Rafik Besbès Bassem Jamoussi 《Green and Sustainable Chemistry》 CAS 2023年第1期62-71,共10页
The olive mill waste waters (OMWW) generated from olive oil extraction is a major environmental concern since they are characterized by their role as a pollutant (high organic and mineral matters) and their pH acid. T... The olive mill waste waters (OMWW) generated from olive oil extraction is a major environmental concern since they are characterized by their role as a pollutant (high organic and mineral matters) and their pH acid. The aim of this study was to valorize (OMWW) by anaerobic fermentation in the presence of cow manure in order to produce biogas and reduce their toxic load. Many tests were carried out by fermenting (OMWW) with polyphenols in the presence of cow manure in thermophile temperatures. The performance of this treatment was valuated through measurements of biogas production and by the determination of different parameters of fermented media (pH, volume of the biogas and polyphenols). 展开更多
关键词 Olive Mill Waste Waters Anaerobic Fermentation cow Manure BIOGAS POLYPHENOLS
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Commercialization of Cow Milk Production in West Hararghe Zone, Oromia National Regional State, Ethiopia
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作者 Azeb Lemma Mengistu Ketema +1 位作者 Jemma Haji Abule Mehare 《Agricultural Sciences》 CAS 2023年第5期710-724,共15页
Livestock plays a vital role in the livelihood of many people in Ethiopia. However, a number of challenges hindered the development of the dairy sector along with its commercialization. Advancing commercialization of ... Livestock plays a vital role in the livelihood of many people in Ethiopia. However, a number of challenges hindered the development of the dairy sector along with its commercialization. Advancing commercialization of the rural generations was a foundation of the advancement and poverty reduction policies of Ethiopia. Cross-sectional data from 385 randomly selected households in Eastern Ethiopia were used in this study to assess the commercialization of cow milk producers. Descriptive statistics and the two limit Tobit econometric models were used to analyze the data. The average commercialization index was 0.434, indicating that each household sold 43.4 percent of the milk produced during the survey period. Ownership of improved breed cow, cooperative participation, access to market information, and quantity of milk produce influenced milk commercialization positively, but household size and distance to the nearest market influenced it negatively. The study suggests strengthening policies to improve rural family planning, strengthening farmer cooperatives to reinforce knowledge sharing among farmers for enhancing farmer resource endowment, and promoting improved breed varieties. The commercialization of milk producers will also expand as a result of policies that try to lower the transaction costs of accessing markets, improve the capacity of rural institutions, and encourage value addition and market links among various market players. 展开更多
关键词 COMMERCIALIZATION cow Milk TOBIT West Hararghe Zone
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Evaluating Fecal Sieving Tool as an Indicator of Feed Valorization and the Impact of Feeding Strategy on Dairy Cow Performance under Farm Conditions
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作者 Nizar Salah Héloïse Legendre +3 位作者 Laurine Faivre Maxime Briche Raphael Gourdon Valentin Nenov 《Agricultural Sciences》 2023年第10期1420-1435,共16页
The objective of this study was to evaluate the use of a faeces sieving tool “Digescan” as an indicator of feed valorization, and to test the influence of feeding strategy on fecal particle size (PS) distribution an... The objective of this study was to evaluate the use of a faeces sieving tool “Digescan” as an indicator of feed valorization, and to test the influence of feeding strategy on fecal particle size (PS) distribution and weight, milk performance and the possible association between them. Data from 95 trials were used. During each trial, two periods were identified: before and during live yeast probiotic (LYP) supplementation. The LYP used at 5 g/d/cow was Saccharomyces cerevisiae (CNCM I-4407, 1010 CFU/g, Actisaf<sup>®</sup> Sc47;Phileo by Lesaffre, France). Milk yield and composition were recorded. Fecal samples were taken at the end of each period and sieved with a set of two wire-mesh screens with pore sizes of 5 mm and 2 mm under running tap water. Yeast probiotic supplementation significantly reduced (P 5 mm was accompanied by 1.2 and 0.65 kg/d decrease in MY, 2.5 and 2 kg/d decrease in ECM and 3.2 and 2.6 kg/d in FCM before and during LYP supplementation, respectively. Fecal particle distribution appears to be a practicable tool to predict influences of feeding systems on feed valorization and performance in dairy cows. Live yeast increases dairy performance and decreases the quantity of fecal particles remaining in the two sieves after rinsing. 展开更多
关键词 Feces Sieving Yeast Probiotic Dairy cow Milk Particle Size
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Influence of Daily Cow Population on Daily Cow Milk Production in Indonesia Period 2009-2019 and Government Policy to Realize White Revolution in
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作者 Sugiartiningsih Eddy Winarso 《Chinese Business Review》 2023年第1期22-30,共9页
The purpose of this study was to determine the effect of the population of dairy cows on milk production of dairy cows in Indonesia for the period 2009-2019 and government policies to realize the white revolution in I... The purpose of this study was to determine the effect of the population of dairy cows on milk production of dairy cows in Indonesia for the period 2009-2019 and government policies to realize the white revolution in Indonesia.The research method used is a descriptive analysis approach regarding the development of the dairy cow population and its relationship to dairy cow’s milk production in Indonesia.The type of data used is annual time series secondary data starting from 2009-2019.Based on the results of the regression,the coefficient value was 0.6677752,indicating that an increase in the population of dairy cows by 1 unit will increase the production of dairy cows in Indonesia by 0.6677752 units.The increase in dairy cow’s milk production is relatively low due to the lack of understanding of local breeders regarding dairy cow rearing and feeding to provide adequate nutrition for cows.Government policies are to realize the white revolution by paying attention to the provision of fresh milk for poor children,counseling local farmers,increasing the economic value of cow waste,and making cooperatives as a place for dairy farmers. 展开更多
关键词 POPULATION PRODUCTION dairy cows white revolution
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基于优化的COW虚拟块设备的虚拟机按需部署机制 被引量:9
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作者 陈彬 肖侬 +1 位作者 蔡志平 王志英 《计算机学报》 EI CSCD 北大核心 2009年第10期1915-1926,共12页
基于COW(Copy-on-Write)读写模式的虚拟块设备有利于实现大规模虚拟机环境下虚拟机的快速部署.文中为虚拟机管理器中的COW虚拟块设备设计了一种优化方法,能够提高COW磁盘的访问性能以及生成多个小尺寸的COW磁盘映像文件,以降低通过网络... 基于COW(Copy-on-Write)读写模式的虚拟块设备有利于实现大规模虚拟机环境下虚拟机的快速部署.文中为虚拟机管理器中的COW虚拟块设备设计了一种优化方法,能够提高COW磁盘的访问性能以及生成多个小尺寸的COW磁盘映像文件,以降低通过网络部署虚拟机的开销.基于优化的COW虚拟块设备,文中提出了虚拟机环境下的虚拟机按需部署机制及关键技术问题的解决方案.基于Linux平台和QEMU虚拟机,实现了基于优化COW虚拟块设备的虚拟机按需部署原型系统.实验表明,优化的COW虚拟块设备、基于COW磁盘有效工作集的优化部署以及COW磁盘回收等方法能够有效地支持虚拟机环境下低开销的、按需的虚拟机部署. 展开更多
关键词 虚拟机 虚拟机管理器 虚拟机按需部署 cow磁盘 有效工作集
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油罐机械清洗设备COW在我国的首次应用 被引量:10
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作者 蒋连生 戴良 +2 位作者 徐峰 贺立平 马成山 《油气储运》 CAS 北大核心 1998年第2期37-41,共5页
对引进日本的机械清洗设备COW,在东营首站第一次使用的情况做了较详细的介绍。该项技术在油罐的清洗中具有机械化程度高、施工周期短、安全可靠、原油回收率高、不会对环境造成污染、综合效益高等优点。同时介绍了COW设备的组成及清洗... 对引进日本的机械清洗设备COW,在东营首站第一次使用的情况做了较详细的介绍。该项技术在油罐的清洗中具有机械化程度高、施工周期短、安全可靠、原油回收率高、不会对环境造成污染、综合效益高等优点。同时介绍了COW设备的组成及清洗施工现场的布置情况,并指出了在今后清洗作业中应注意的事项。 展开更多
关键词 油罐 cow 机械清洗设备 维修
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CoW_(11)Ti/淀粉纳米复合物的合成与表征 被引量:2
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作者 王晓红 王立敏 +1 位作者 李凤 刘景福 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2003年第12期2158-2160,共3页
Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectrosco... Using a reversed-phase microemulsion polymerization method, polyoxometalates(POMs) CoW 11Ti loaded starch nanoparticles were prepared and structurally characterized by elemental analyses, IR, UV-Vis and ESR spectroscopy. The particle size of CoW 11Ti/starch was estimated by transmission electron microscope(TEM) and the size ranges by a 1000HSA MALVIRN Zetasizer instrument. The result shows that the polyoxometalate retained the parent structure after encapsulated by starch microspheres, which are able to enhance the stability and antitumoral activity of POMs and decrease the toxicity of POMs as well. 展开更多
关键词 多酸化合物 K6H2[cow11TiO40]·12H2O 淀粉纳米粒子 载药体系 合成 表征 抗HIV病毒活性 抗肿瘤活性
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K_5CoW_(12)O_(40)·3H_2O催化合成苯甲醛1,2-丙二醇缩醛 被引量:5
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作者 赖君玲 刘春生 +1 位作者 罗根祥 沈飞 《辽宁石油化工大学学报》 CAS 2010年第2期1-3,共3页
研究了K5CoW12O40.3H2O催化剂对苯甲醛和1,2-丙二醇为原料合成苯甲醛1,2-丙二醇缩醛的反应的催化活性。考察了醛醇物质的量比、催化剂质量、带水剂体积、反应时间、催化剂重复使用性等因素对产品收率的影响。结果表明,K5CoW12O40.3H2O... 研究了K5CoW12O40.3H2O催化剂对苯甲醛和1,2-丙二醇为原料合成苯甲醛1,2-丙二醇缩醛的反应的催化活性。考察了醛醇物质的量比、催化剂质量、带水剂体积、反应时间、催化剂重复使用性等因素对产品收率的影响。结果表明,K5CoW12O40.3H2O是缩醛反应的良好催化剂。在最佳实验条件下:苯甲醛与1,2-丙二醇物质的量比为1:1.2、苯甲醛物质的量为0.1mol、催化剂质量为0.3g、环己烷体积为10mL、反应时间45min,苯甲醛1,2-丙二醇缩醛的收率最高可达92.8%。 展开更多
关键词 苯甲醛l 2-丙二醇缩醛 K5cow12O40·3H2O 催化 缩醛反应
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并行多种群自适应遗传算法在COW集群上的实现 被引量:1
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作者 刘虎 张焕春 +1 位作者 经亚枝 朱力立 《南京航空航天大学学报》 EI CAS CSCD 北大核心 2005年第6期760-765,共6页
为改善标准遗传算法的求解效率,提出一种基于6模糊控制器的并行多种群自适应遗传算法。利用MPI(Messagepassinginterface)技术建立了一个COW(Clusterofworkstation)集群,将算法在该硬件平台上进行了实现。3机COW集群的仿真实验结果在演... 为改善标准遗传算法的求解效率,提出一种基于6模糊控制器的并行多种群自适应遗传算法。利用MPI(Messagepassinginterface)技术建立了一个COW(Clusterofworkstation)集群,将算法在该硬件平台上进行了实现。3机COW集群的仿真实验结果在演示算法设计可行性的同时,表明该算法的求解效率明显优于用于对照的单种群算法,具有在解决组合优化问题上广泛应用的可能。本文还对影响并行算法的参数进行了探讨。 展开更多
关键词 并行遗传算法 自适应参数控制 cow集群 MPI
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CeO_2-TiO_2/[CoW_(12)O_(40)]^(5-)-HTLC的制备及光催化性能 被引量:1
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作者 薛茹君 周敏 +1 位作者 陈淑芬 陈春阳 《安徽理工大学学报(自然科学版)》 CAS 2013年第1期5-9,共5页
为了克服杂多酸易溶于极性溶剂,较难回收重复使用的缺点,采用共沉淀法制备了镁铝水滑石;并以硝酸根型水滑石作为前体,通过插层组装合成了杂多阴离子[CoW12O40]5--HTLC;再采用微乳液法将CeO2掺杂的TiO2负载到[CoW12O40]5--HTLC上,焙烧后... 为了克服杂多酸易溶于极性溶剂,较难回收重复使用的缺点,采用共沉淀法制备了镁铝水滑石;并以硝酸根型水滑石作为前体,通过插层组装合成了杂多阴离子[CoW12O40]5--HTLC;再采用微乳液法将CeO2掺杂的TiO2负载到[CoW12O40]5--HTLC上,焙烧后得到CeO2-TiO2/[CoW12O40]5--HTLC光催化剂。采用XRD、FT-IR、SEM-EDS和UV-Vis漫反射光谱等手段对催化剂进行了表征;以甲基橙为模拟污染物,考察了催化剂样品的光催化性能。实验结果表明:CeO2掺杂TiO2复合粒子在可见光区吸光性能高于TiO2;CeO2掺杂TiO2与杂多阴离子[CoW12O40]5-有协同光催化作用,CeO2-TiO2/[CoW12O40]5--HTLC光催化剂对可见光的吸收大大增强。经模拟日光照射2 h,15%(CeO2-TiO2)/5%[CoW12O40]5--HTLC催化剂对甲基橙的脱色率达到93%。 展开更多
关键词 CeO2-TiO2/[cow12O40]5--HTLC 光催化剂 制备 性能
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