Background:High stocking density(HSD)stress has detrimental effects on growth performance,intestinal barrier function,and intestinal microbiota in intensive animal production.Organic acids(OA)are widely used as feed a...Background:High stocking density(HSD)stress has detrimental effects on growth performance,intestinal barrier function,and intestinal microbiota in intensive animal production.Organic acids(OA)are widely used as feed addi-tives for their ability to improve growth performance and intestinal health in poultry.However,whether dietary OA can ameliorate HSD stress-induced impaired intestinal barrier in broilers remains elusive.In this study,a total of 528 one-day-old male Arbor Acres broilers were randomly allocated into 3 treatments with 12 replicates per treatment including 10 birds for normal stocking density and 17 birds for HSD.The dietary treatments were as follows:1)Normal stocking density+basal diet;2)HSD+basal diets;3)HSD+OA.Results:HSD stress can induce increased levels of serum corticosterone,lipopolysaccharides,interleukin-1β,tumor necrosis factor-α,and down-regulated mRNA expression of ZO-1,resulting in compromised growth performance of broilers(P<0.05).Dietary OA could significantly reduce levels of serum corticosterone,lipopolysaccharides,interleukin-1β,and tumor necrosis factor-α,which were accompanied by up-regulated interleukin-10,mRNA expres-sion of ZO-1,and growth performance(P<0.05).Moreover,OA could down-regulate the mRNA expression of TLR4 and MyD88 to inhibit the NF-κB signaling pathway(P<0.05).Additionally,HSD stress significantly decreased the abundance of Bacteroidetes and disturbed the balance of microbial ecosystems,whereas OA significantly increased the abundance of Bacteroidetes and restored the disordered gut microbiota by reducing competitive and exploita-tive interactions in microbial communities(P<0.05).Meanwhile,OA significantly increased the content of acetic and butyric acids,which showed significant correlations with intestinal inflammation indicators(P<0.05).Conclusions:Dietary OA ameliorated intestinal inflammation and growth performance of broilers through restor-ing the disordered gut microbial compositions and interactions induced by HSD and elevating short-chain fatty acid production to inhibit the TLR4/NF-κB signaling pathway.These findings demonstrated the critical role of intestinal microbiota in mediating the HSD-induced inflammatory responses,contributing to exploring nutritional strategies to alleviate HSD-induced stress in animals.展开更多
Atlantic salmon reared in recirculating aquaculture system(RAS) may lead to inappropriately high stocking density, because ?sh live in a limited space. Finding the suitable stocking density of Atlantic salmon reared i...Atlantic salmon reared in recirculating aquaculture system(RAS) may lead to inappropriately high stocking density, because ?sh live in a limited space. Finding the suitable stocking density of Atlantic salmon reared in RAS is very important for RAS industry. In this paper, the in?uence of stocking density on growth and some stress related physiological factors were investigated to evaluate the ef fects of stocking density. The ?sh were reared for 220 days at ?ve densities(A: 24 kg/m^3; B: 21 kg/m^3; C: 15 kg/m^3; D: 9 kg/m^3 and E: 6 kg/m^3). The results show that 30 kg/m^3 might be the maximum density which RAS can af ford in China. The stocking densities under 30 kg/m^3 have no ef fect on mortality of Atlantic salmon reared in RAS. However, the speci?c growth rate(SGR), ?nal weight and weight gain in the high density group were signi?cantly lower than the lower density groups and middle density groups. Moreover, feed conversion rate(FCR) had a negative correlation with density. Plasma hormone T_3 and GH showed signi?cant decrease with the increase of the stocking density of the experiment. Furthermore, thyroid hormone(T 3), GH(growth hormone) activities were decreased with stocking density increase. However, plasma cortisol, GOT(glutamic oxalacetic transaminase) and GPT(glutamic pyruvic transaminase) activities were increase with stocking density increase. And the stocking density has no ef fects on plasma lysozyme of Atlantic salmon reared in RAS. These investigations would also help devise effcient ways to rear adult Atlantic salmon in China and may, in a way, help spread salmon mariculture in China.展开更多
The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout(Oncorhynchus mykiss). Pen-reared ...The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout(Oncorhynchus mykiss). Pen-reared trout were stocked in densities of 40, 60, 80 fish individuals m^(-3)(4.6, 6.6, 8.6 kg m^(-3), SD1, SD2 and SD3 groups, respectively) for 300 days. Compared to the water from SD1 and SD2, that from SD3 exhibited significantly higher NH_4^+-N content and COD(chemical-oxygen-demand), and a significant reduction of dissolved oxygen in day 180(40.6 kg m^(-3)). Stocking density was significantly associated with body weight, standard length, VSI(viscerosomatic index), CF(condition factor) and FC(food coefficient) in group SD3, particularly in day 240 and day 300(45 or 49.3 kg m^(-3)). Increased crude fat and decreased crude protein were displayed in high density group when the density reached to 36 kg m^(-3). As a cumulative effect of density-related stress, VSI, CF, FC, moisture, and crude protein content varied over time in each density group(SD1, SD2, and SD3). In summary, trout exhibited a better growth performance in low density(26.3 kg m^(-3)) than those reared in high densities(36 and 45 kg m^(-3)). The results indicate that rainbow trout(114.44 g ± 6.21 g, 19.69 cm ± 0.31 cm) initially stocked in 6.6 or 8.6 kg m^(-3) should be lightened to less than 36 kg m^(-3) after an intensive rearing for 240 days.展开更多
Stocking density is an important factor for animal production performance.It appears particularly urgent and important to research systematically on stocking density for the dual restriction of environmental protectio...Stocking density is an important factor for animal production performance.It appears particularly urgent and important to research systematically on stocking density for the dual restriction of environmental protection and animal welfare.This review dealt with the influence of stocking density on ducks'productivity and health through production performance,animal behavior and animal welfare,and analyzed the possible mechanism of high stocking density reducing production performance,resulting in abnormal behavior and stress,causing welfare and health problems.We consider that it might be associated with heat stress,more spatial competition(to gather the food,drinking water,sports area,etc.),as well as the quality deterioration of litter and house air caused by high stocking density.Finally,we put forward some suggestions on the study of stocking density's effects on ducks,and proposed the future work that need to be studied and problems that need to be solved imminently.展开更多
The inadequate supply of tilapia fingerling is a major limitation to cage culture development in Ghana. Lake-based hapa systems are very efficient in nursing fingerlings although the process can be tricky due to inher...The inadequate supply of tilapia fingerling is a major limitation to cage culture development in Ghana. Lake-based hapa systems are very efficient in nursing fingerlings although the process can be tricky due to inherent effects of stocking densities and environmental factors. This study aimed at assessing the growth, survival and profitability of Nile tilapia (Oreochromis niloticus) fingerlings of the Akosombo strain reared in nine 1 m<sup>3</sup> Lake-based hapas at different densities. Each hapa was stocked with 2.12 ± 0.14 g sex-reversed tilapia fingerlings at varying stocking densities of 400 fish/m<sup>3</sup>, 800 fish/m<sup>3</sup> and 1200 fish/m<sup>3</sup> serving as treatments T1, T2 and T3 respectively. Each treatment was replicated thrice. Bi-weekly samplings were done and water quality parameters were measured. After the experiment, analysis of variance showed significant differences (p展开更多
Effects of various seedling classes and root cutting treatments on the survival rate, stocking Percentage and the growth of height and collar diameter in young stands of korean pine (Pinus koraiensis), mongolian scots...Effects of various seedling classes and root cutting treatments on the survival rate, stocking Percentage and the growth of height and collar diameter in young stands of korean pine (Pinus koraiensis), mongolian scots pine (Pin us sylvestris var.mangolica),Dahurian larch (Larix gmelini), korean spruce (Picea koraiensis), anur cork tree(Phellodendron amurensis). manchurian ash (Fradinus mandshurica) and anur linden (Tilia amurensis) were studied in this paper. The results show that the survival rate, stocking Percentage and the growth of height and collar diameter of the I class seedlings are better than that of the n and III classes seedlings. so it is very important to select I class seedlings for increasing the quality of afforestation.展开更多
The Pacific oyster Crassostrea gigas is one of the most widely cultivated aquaculture species and contributes signifi-cantly to total seafood production for human beings.However,mass mortality occurred frequently,and ...The Pacific oyster Crassostrea gigas is one of the most widely cultivated aquaculture species and contributes signifi-cantly to total seafood production for human beings.However,mass mortality occurred frequently,and in some regions almost all oysters died during seed production and grow-out stage.In order to explore whether hybridization breeding can improve its growth and survival,a complete diallel cross between a selected strain‘Haida No.1’(S)and an orange shell variant(O)of C.gigas was carried out.The larval growth and survival were compared among hybrids and purebred strains at temperatures of 16,20,24,28 and 32℃;salinities of 15,20,25,30 and 35;and stocking densities of 0.5,1,2,4 and 8 larvae mL−1.Under different environments,the hybridization between two strains of C.gigas showed the heterosis of growth and survival.The mean shell height and survival rate of the two reciprocal crosses(OS,SO)were significantly higher than those of the two purebred strains(SS,OO)under all environ-mental conditions.In particular,OS showed greater heterosis than the purebred strains and SO progeny.The results showed that the productive traits of the‘Haida No.1’could be improved by crossing with the orange shell line.Meanwhile,the results from this study also indicated that hybridization between the two strains of C.gigas may be a promising way for breeding new variety with high survival rate.展开更多
Silvicultural practices applied in managed forest plantations may help counteract the effects of climate change by influencing soil surface CO_(2)efflux(Fs).Understanding the effects of silvicultural practices on Fs w...Silvicultural practices applied in managed forest plantations may help counteract the effects of climate change by influencing soil surface CO_(2)efflux(Fs).Understanding the effects of silvicultural practices on Fs will provide unbiased estimates of carbon fluxes and allow better silvicultural decisions for carbon sequestration.Therefore,we assessed how Fs differed seasonally across silvicultural practices(i.e.,stocking levels,clone,fertilization and weed control treatments)and evaluated the effects of soil temperature(Ts)and soil volumetric water content(θv)on Fs across these practices for a mid-rotation(14 year-old)Pinus radiata plantation in the Canterbury region of New Zealand.There were significant differences in Fs(p<0.05)over the four seasons,three levels of stocking,and five clones.The effects of fertilization and weed control applied 12 years previously on Fs were insignificant.Annual estimate of Fs(mean±1 standard deviation)from the study site was 22.7±7.1 t ha^(-1)a^(-1)in the form of CO_(2)(6.2±2.1 t ha^(-1)a^(-1)in the form of C).Fs values were consistently higher in plots with 1250 stems ha^(-1)compared to 2500 stems ha^(-1),which may be related to a strong soil resource limitation because of the close spacing in the latter plantation.Significant differences in Fs across clones suggest that variations in carbon partitioning might explain their growth performance.Silvicultural treatments influenced Fs response to soil temperature(p<0.05),resulting in models explaining 28-49%of the total variance in Fs.These findings provide insights into how silvicultural management decisions may impact Fs in mid-rotation radiata pine plantations,contributing towards developing more precise and unbiased plantation carbon budgets.展开更多
A series of self-designed and woven compression stockings were used in this pressure comparison experiment. In order to compare the differences of the garment pressure values exerted by the compression stockings with ...A series of self-designed and woven compression stockings were used in this pressure comparison experiment. In order to compare the differences of the garment pressure values exerted by the compression stockings with different structure parameters among three methods. The experiments were carried out with Flexi force sensors. The pressure value of nine pairs of compression stockings on five subjects and the model leg was collected, and the tensile force of the every section of these stockings was collected to calculate the pressure according to Laplace's equation. The data analysis results show that the pressure values of the compression stockings obtained by comparing the three methods have great differences in various testing methods. There is a significant correlation between processing parameters and stitch density(SD). The pressure design of the compression stockings should be based on the actual wearing of the pressure.展开更多
Stocking of Lake Kinneret by exotic fish species (Mugilids: Mugil cephalus and Liza ramada) started in 1958. The rational stocking of Lake Kinneret with Mugilids was double functioned: To improve fishermen income and ...Stocking of Lake Kinneret by exotic fish species (Mugilids: Mugil cephalus and Liza ramada) started in 1958. The rational stocking of Lake Kinneret with Mugilids was double functioned: To improve fishermen income and the water quality in the lake. Mugilids are chosen as introduction target because their market value is high, the fish cannot reproduce in the lake and fingerlings are low cost available. During 1960-2015, 56.2 million fingerlings were introduced into the lake approximately averaged one million per year of M. cephalus (MC) and L. ramada (LR). The study of the Mugilids food composition has indicated consumption of suspensoids, mostly detritial organic particles. Therefore no damage to water quality is suggested. The best fitness between recruitment to Dock on Side landings and stocking capacity was evaluated at 3 years interval. Differences were found between recruitments of MC and LR to commercial catches by individual averaged age and weight. The long term success of Mugilid introduction to Lake Kinneret is confirmed.展开更多
Urochloa brizantha (synonymous of Brachiaria) is the most spread species of grass in the tropical world, primarily in regions with acid and low fertility soils. This study was conducted to investigate changes in the s...Urochloa brizantha (synonymous of Brachiaria) is the most spread species of grass in the tropical world, primarily in regions with acid and low fertility soils. This study was conducted to investigate changes in the soil chemical properties of a Typical Acrudox submitted to a strategy of grazing with rotational stocking, liming and nitrogen fertilisation. Treatments involved combinations of two pre-grazing heights (25 and 35 cm) with two rates of nitrogen (50 and 200 kg·ha-1·year-1). All combinations received lime, P and K fertilization and an untreated control group was allocated according to a complete randomised block design, five replications. Soil sampling was done in layers of 0-5, 5-10, 10-20, 20-30 and 30-40 cm deep in pastures of U. brizantha Marandu (Palisade grass). The samples were analysed for pH, H+ + Al3+, soil organic matter (SOM), P, K+, Ca2+, Mg2+, exchangeable and calculated CEC, BS% and aluminium saturation. Liming and fertilisation improve the soil fertility. The highest organic matter contents were obtained for the 0-5 cm layer, with a nitrogen fertilisation of 200 kg·N·ha-1. The management practice for the pre-grazing height of 25 cm, regardless of the nitrogen, is the best strategy for soil quality and livestock production.展开更多
A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three ...A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three stocking density on growth performances, production traits, feed utilization and body composition. Nine cages 24 m3 each (4 × 6 × 1.5 m, long, width and height) were stocked with either 1200, 3600 and 6000 fish for each cage to give a stocking rate of 50, 150, and 250 fish/m3 respectively and fish fed daily, slightly in excess of satiation to eliminate the possibility of food supply being a limiting factor to growth. The results revealed that, mean final weight (g/fish), gain in weight, SGR (%per day), feed conversion ratio, protein efficiency ratio and total feed intake (g/fish) were significantly (P ≤ 0.01) influenced. The best at the lowest stocking density, while, the total production and net production exhibited significantly the opposite trend. Harvest and production estimates increased with increasing stocking density. Fish body composition% of moisture, protein, fat and ash were significantly (P ≤ 0.01) influenced by stocking density. From the above results and the economic information of the study, it can be concluded that stocking density of 50 fish/m3 of meagre exhibited the highest net profit and would seem to be the most desirable density in the system studied.展开更多
Chronic fatigue syndrome and myalgic encephalomyelitis (CFS/ME) are, amongst others, characterized by exercise intolerance, pain, post exertional malaise and orthostatic intolerance. It has been shown in venous diseas...Chronic fatigue syndrome and myalgic encephalomyelitis (CFS/ME) are, amongst others, characterized by exercise intolerance, pain, post exertional malaise and orthostatic intolerance. It has been shown in venous disease and sport participation that compression stockings may improve exercise performance and reduce post exercise muscle soreness. Moreover, its use is advocated in orthostatic hypotension. Therefore, it was hypothesized that compression stockings may reduce symptomatology in CFS/ME patients. Methods: 100 patients used compression stockings class II for minimally 3 weeks and thereafter filled in a questionnaire, based on the Rand 36 physical activity questions (n = 9), whether compression stockings changed perceived symptoms or not. Moreover, 7 questions referring to prolonged standing and sitting, to recovery post exercise, muscle pain during or immediately post exercise, and to dizziness/light-headedness during or immediately post exercise, while standing and during prolonged sitting were added. Questions were scored as 1: able to perform activity much less while wearing the stockings, 2: perform activity somewhat less, 3: no perceived change in activity, 4: perform activity slightly better, 5: able to perform activity much better while wearing the stockings. Results: In patients able to answer the question, all mean scores per activity were significantly higher than 3, being no perceived change in activity while wearing the stockings. Subgroup analysis showed that patients with orthostatic intolerance reported higher effects than patients without orthostatic intolerance. Conclusion: This pilot study suggests that compression stockings may be useful to reduce symptomatology of physical activities in CFS/ME patients, especially in patients with orthostatic intolerance. Larger prospective studies with hard endpoints are warranted.展开更多
Shrimps are recognized as the white gold of Bangladesh because it is the second largest export earning product after garments sector.The brown shrimp(M.monoceros)have high growth rates together with that they tol...Shrimps are recognized as the white gold of Bangladesh because it is the second largest export earning product after garments sector.The brown shrimp(M.monoceros)have high growth rates together with that they tolerate wide ranges of salinity and environmental parameters which makes them highly attractive for culture purposes.The purposes of this research were to assess the cultural performance and economic profitability of brown shrimp(Metapenaeus monoceros)in brackish water ponds.This research lasted from February to June 2020 under three different stocking densities such as 35,45 and 55 individuals/m2 in treatments T1,T2 and T3 at Bangladesh Fisheries Research Institute,Brackishwater Station,Paikgacha,Khulna.After 90 days culture periods the total production was 1703.32±144.48,2768.25±167.63 and 2535.03±253.52 kg/ha in T1,T2 and T3 respectively which was significantly higher(p<0.05)in T2 compared to T1 and T2.Benefit cost ratio(BCR)was 0.32,0.87 and 0.52 in T1,T2 and T3 respectively and found significantly higher(p<0.05)in T2 than T1 and T3.Both cultural performance and economic analysis imply that brown shrimp(M.monoceros)with a stocking density of 450000 individuals/ha might be environment conciliatory and economically enduring in coastal areas of Bangladesh.展开更多
Fry stocking density can affect harvest metrics for fingerling walleye (Stizostedion vitreum) reared in drainable ponds, but few studies have examined these relationships with the use of elevated walleye fry stocking ...Fry stocking density can affect harvest metrics for fingerling walleye (Stizostedion vitreum) reared in drainable ponds, but few studies have examined these relationships with the use of elevated walleye fry stocking densities in lined ponds. Correlation and regression analyses were used to assess how a three-fold change in walleye fry stocking density (234,375 to 703,125 per hectare) relates to harvest metrics and length of the culture period, as well as the tradeoff experienced between walleye size (grams) and harvest density in 0.32-hectare lined ponds over a nine-year period at Blue Dog State Fish Hatchery, South Dakota. As fry stocking density increased, so did harvest metrics for both number (r = 0.85, P < 0.01) and yield (r = 0.81, P < 0.01). Length of the culture period varied between 24 and 35 days and was negatively related to stocking density (r = -0.66, P The linear relationship between harvest density and yield was highly correlated (r = 0.95, P < 0.01) with highest values measuring 617,625 walleye and 173 kilograms per hectare. Harvest density explained 61% of the variation in walleye size (P 0.01) and exhibited a decreasing curvilinear relationship such that continued increases in harvest density resulted in smaller reductions in fish size. Increasing fry stocking density from 234,375 to 703,125 per hectare in lined ponds coincided with increased rearing efficiencies for number and yield, as well as a reduced culture period. Minimal reduction in walleye size occurred once harvest density exceeded 300,000 per hectare.展开更多
This study was conducted to evaluate the effects of different stocking densities on growth performance,blood parameters,intestinal morphology and intestinal immunity of growing pigs.A total of288 male pigs(44.35±...This study was conducted to evaluate the effects of different stocking densities on growth performance,blood parameters,intestinal morphology and intestinal immunity of growing pigs.A total of288 male pigs(44.35±0.50 kg)were randomly assigned to groups with stocking densities of 2.46,1.23 and 0.82 m2/pig for a month.The results showed that there was no significant difference on growth performance among groups.Pigs in the stocking density of 0.82 m2/pig had the lowest backfat thickness and spleen weight index among groups(P<0.05).With increasing stocking density,the serum concentrations of blood urea nitrogen(BUN),transglutaminase(TGG),alkaline phosphatase(AKP)and immunoglobulin A(Ig A)were increased,and albumin(ALB),albumin-to-globulin ratio(ALB:GLO),insulin-like growth factor-1(IGF-1)and immunoglobulin(Ig M)were decreased(P<0.05),and cortisol tended to increase and glucose tended to decrease(0.05<P<0.1).Compared with the stocking density of 2.46 m2/pig,the ileal villus height and jejunal villus width decreased in stocking densities of 1.23 and 0.82 m2/pig(P<0.05).The duodenal villus height and ileal villus width in the stocking density of 0.82 m2/pig were the lowest among 3 groups(P<0.05).The content of immunoglobulin A in duodenum,jejunum and ileum mucosa increased along with increasing density(P<0.05).The contents of interleukin(IL)-2 in the spleen or liver and IL-10 in the spleen were higher in the stocking density of 0.82 m2/pig than in other 2 groups.These results showed that stocking density could affect the metabolism,intestinal morphology,and immunity of growing pigs and 1.23 m2/pig may be the suitable stocking density for the growing pigs in the present study.展开更多
The present study was conducted to evaluate the effects of dietary gamma-aminobutyric acid(GABA)in broiler chickens raised in high stocking density(HSD)on performance and physiological responses.A total of 900 male br...The present study was conducted to evaluate the effects of dietary gamma-aminobutyric acid(GABA)in broiler chickens raised in high stocking density(HSD)on performance and physiological responses.A total of 900 male broiler chicks(Ross 308)at 1 d old were assigned in a 2×2 factorial arrangement to 4 treatments(10 replicates per treatment)with stocking density,7.5 birds/m^2(low stocking density;LSD)or 15 birds/m^2(HSD),and dietary GABA,0 or 100 mg/kg.Chickens raised in HSD exhibited a decrease in body weight gain in all phases(P<0.05)and feed intake in starter and whole phases(P<0.01),and an increase in feed conversion ratio in the finisher phase(P<0.01)compared with LSD-raised chickens.However,dietary GABA did not affect growth performance nor interacted with stocking density on production variables.The HSD vs.LSD increased relative liver weight on d 35 whereas dietary GABA increased relative liver weight and decreased relative bursa weight on d 21.Both stocking density and dietary GABA affected yield and quality of breast and leg muscles.Dietary GABA increased(P<0.05)width of tibia on d 35 and interacted(P=0.054)with stocking density on breaking stocking density on d 35.The HSD vs.LSD group lowered(P<0.05)feather coverage scores.Significant interaction between stocking density and GABA on surface temperature of shank on d 21 was noted(P=0.024).Dietary GABA exhibited an opposite effect on the concentrations of cecal short-chain fatty acids depending on stocking density leading to a moderate to significant interaction.Stocking density decreased alpha-1-acid glycoprotein whereas dietary GABA decreased heterophil-to-lymphocyte ratio and corticosterone in blood or serum samples.Serum biochemical parameters were altered by stocking density or dietary GABA.It is concluded that dietary GABA alleviated stress indices including corticosterone and heterophilto-lymphocyte ratio,but failed to reverse stocking density-induced growth depression.展开更多
In this paper, a three species difFusive predator-prey modei with functional response and periodic stocking is studied, where all parameters are time depen-dent. By using new theorem of coincidence degree theory, the ...In this paper, a three species difFusive predator-prey modei with functional response and periodic stocking is studied, where all parameters are time depen-dent. By using new theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established.展开更多
Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic conditions.The A...Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic conditions.The African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,Ethiopia.Smallholder farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,etc.These trees also could improve soil fertility.However,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological systems.Hence,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental conditions.We divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different depths.We collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil depth.Bulk density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were analysed.Results revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under A.leiocarpus,and soil p H under S.kunthianum,all the studied soils were improved under both species canopy as compared with canopy gap.SMC,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under control.The two parkland agroforestry species significantly enhanced soil fertility near the canopy of topsoil through improving soil physical and chemical properties.These two species were recommended in the drylands with similar agro-ecological systems.展开更多
The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment ...The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits.展开更多
基金supported by the Agricultural Science and Technology Innovation Program(ASTIP)of the Chinese Academy of Agricultural Sciences,and Trouw Nutrition Research&Development Centers.
文摘Background:High stocking density(HSD)stress has detrimental effects on growth performance,intestinal barrier function,and intestinal microbiota in intensive animal production.Organic acids(OA)are widely used as feed addi-tives for their ability to improve growth performance and intestinal health in poultry.However,whether dietary OA can ameliorate HSD stress-induced impaired intestinal barrier in broilers remains elusive.In this study,a total of 528 one-day-old male Arbor Acres broilers were randomly allocated into 3 treatments with 12 replicates per treatment including 10 birds for normal stocking density and 17 birds for HSD.The dietary treatments were as follows:1)Normal stocking density+basal diet;2)HSD+basal diets;3)HSD+OA.Results:HSD stress can induce increased levels of serum corticosterone,lipopolysaccharides,interleukin-1β,tumor necrosis factor-α,and down-regulated mRNA expression of ZO-1,resulting in compromised growth performance of broilers(P<0.05).Dietary OA could significantly reduce levels of serum corticosterone,lipopolysaccharides,interleukin-1β,and tumor necrosis factor-α,which were accompanied by up-regulated interleukin-10,mRNA expres-sion of ZO-1,and growth performance(P<0.05).Moreover,OA could down-regulate the mRNA expression of TLR4 and MyD88 to inhibit the NF-κB signaling pathway(P<0.05).Additionally,HSD stress significantly decreased the abundance of Bacteroidetes and disturbed the balance of microbial ecosystems,whereas OA significantly increased the abundance of Bacteroidetes and restored the disordered gut microbiota by reducing competitive and exploita-tive interactions in microbial communities(P<0.05).Meanwhile,OA significantly increased the content of acetic and butyric acids,which showed significant correlations with intestinal inflammation indicators(P<0.05).Conclusions:Dietary OA ameliorated intestinal inflammation and growth performance of broilers through restor-ing the disordered gut microbial compositions and interactions induced by HSD and elevating short-chain fatty acid production to inhibit the TLR4/NF-κB signaling pathway.These findings demonstrated the critical role of intestinal microbiota in mediating the HSD-induced inflammatory responses,contributing to exploring nutritional strategies to alleviate HSD-induced stress in animals.
基金Supported by the National Science Foundation for Young Scientists of China(No.31402314,31402283)the Agency of Science and Technology of Shandong Province(No.2013GHY11514)+4 种基金the Modern Agro-Industry Technology Research System(No.nycytx-50)the Scientific and Technology Innovation Project Financially Supported by Qingdao National Laboratory for Marine Science and Technology(Nos.2015ASKJ02,2015ASKJ02-03-03)the Youth Innovation Promotion Association CAS,the Chinese Academy of Science and Technology Service Network Planning(No.KFJ-EW-STS-060)the China Agriculture Research System(No.CARS-47)the Shandong Provincial Key S&T Innovation Project(No.2017CXGC0101)
文摘Atlantic salmon reared in recirculating aquaculture system(RAS) may lead to inappropriately high stocking density, because ?sh live in a limited space. Finding the suitable stocking density of Atlantic salmon reared in RAS is very important for RAS industry. In this paper, the in?uence of stocking density on growth and some stress related physiological factors were investigated to evaluate the ef fects of stocking density. The ?sh were reared for 220 days at ?ve densities(A: 24 kg/m^3; B: 21 kg/m^3; C: 15 kg/m^3; D: 9 kg/m^3 and E: 6 kg/m^3). The results show that 30 kg/m^3 might be the maximum density which RAS can af ford in China. The stocking densities under 30 kg/m^3 have no ef fect on mortality of Atlantic salmon reared in RAS. However, the speci?c growth rate(SGR), ?nal weight and weight gain in the high density group were signi?cantly lower than the lower density groups and middle density groups. Moreover, feed conversion rate(FCR) had a negative correlation with density. Plasma hormone T_3 and GH showed signi?cant decrease with the increase of the stocking density of the experiment. Furthermore, thyroid hormone(T 3), GH(growth hormone) activities were decreased with stocking density increase. However, plasma cortisol, GOT(glutamic oxalacetic transaminase) and GPT(glutamic pyruvic transaminase) activities were increase with stocking density increase. And the stocking density has no ef fects on plasma lysozyme of Atlantic salmon reared in RAS. These investigations would also help devise effcient ways to rear adult Atlantic salmon in China and may, in a way, help spread salmon mariculture in China.
基金supported by Special Fund for Agroscientific Research in the Public Interest (2010 03055)
文摘The goal of the study was to examine the effect of stocking density on the water quality of culture area, as well as the growth, body composition and cortisol content of rainbow trout(Oncorhynchus mykiss). Pen-reared trout were stocked in densities of 40, 60, 80 fish individuals m^(-3)(4.6, 6.6, 8.6 kg m^(-3), SD1, SD2 and SD3 groups, respectively) for 300 days. Compared to the water from SD1 and SD2, that from SD3 exhibited significantly higher NH_4^+-N content and COD(chemical-oxygen-demand), and a significant reduction of dissolved oxygen in day 180(40.6 kg m^(-3)). Stocking density was significantly associated with body weight, standard length, VSI(viscerosomatic index), CF(condition factor) and FC(food coefficient) in group SD3, particularly in day 240 and day 300(45 or 49.3 kg m^(-3)). Increased crude fat and decreased crude protein were displayed in high density group when the density reached to 36 kg m^(-3). As a cumulative effect of density-related stress, VSI, CF, FC, moisture, and crude protein content varied over time in each density group(SD1, SD2, and SD3). In summary, trout exhibited a better growth performance in low density(26.3 kg m^(-3)) than those reared in high densities(36 and 45 kg m^(-3)). The results indicate that rainbow trout(114.44 g ± 6.21 g, 19.69 cm ± 0.31 cm) initially stocked in 6.6 or 8.6 kg m^(-3) should be lightened to less than 36 kg m^(-3) after an intensive rearing for 240 days.
基金Supported by Chinese National Key Research and Development Program(2016YFD0500510).
文摘Stocking density is an important factor for animal production performance.It appears particularly urgent and important to research systematically on stocking density for the dual restriction of environmental protection and animal welfare.This review dealt with the influence of stocking density on ducks'productivity and health through production performance,animal behavior and animal welfare,and analyzed the possible mechanism of high stocking density reducing production performance,resulting in abnormal behavior and stress,causing welfare and health problems.We consider that it might be associated with heat stress,more spatial competition(to gather the food,drinking water,sports area,etc.),as well as the quality deterioration of litter and house air caused by high stocking density.Finally,we put forward some suggestions on the study of stocking density's effects on ducks,and proposed the future work that need to be studied and problems that need to be solved imminently.
文摘The inadequate supply of tilapia fingerling is a major limitation to cage culture development in Ghana. Lake-based hapa systems are very efficient in nursing fingerlings although the process can be tricky due to inherent effects of stocking densities and environmental factors. This study aimed at assessing the growth, survival and profitability of Nile tilapia (Oreochromis niloticus) fingerlings of the Akosombo strain reared in nine 1 m<sup>3</sup> Lake-based hapas at different densities. Each hapa was stocked with 2.12 ± 0.14 g sex-reversed tilapia fingerlings at varying stocking densities of 400 fish/m<sup>3</sup>, 800 fish/m<sup>3</sup> and 1200 fish/m<sup>3</sup> serving as treatments T1, T2 and T3 respectively. Each treatment was replicated thrice. Bi-weekly samplings were done and water quality parameters were measured. After the experiment, analysis of variance showed significant differences (p
文摘Effects of various seedling classes and root cutting treatments on the survival rate, stocking Percentage and the growth of height and collar diameter in young stands of korean pine (Pinus koraiensis), mongolian scots pine (Pin us sylvestris var.mangolica),Dahurian larch (Larix gmelini), korean spruce (Picea koraiensis), anur cork tree(Phellodendron amurensis). manchurian ash (Fradinus mandshurica) and anur linden (Tilia amurensis) were studied in this paper. The results show that the survival rate, stocking Percentage and the growth of height and collar diameter of the I class seedlings are better than that of the n and III classes seedlings. so it is very important to select I class seedlings for increasing the quality of afforestation.
基金supported by the National Natural Science Foundation of China (Nos. 31972789 and 31772843)the Industrial Development Project of Qingdao City (No. 20-3-4-16-nsh)the Science and Technology Development Project of Weihai City (No. 2018NS01)
文摘The Pacific oyster Crassostrea gigas is one of the most widely cultivated aquaculture species and contributes signifi-cantly to total seafood production for human beings.However,mass mortality occurred frequently,and in some regions almost all oysters died during seed production and grow-out stage.In order to explore whether hybridization breeding can improve its growth and survival,a complete diallel cross between a selected strain‘Haida No.1’(S)and an orange shell variant(O)of C.gigas was carried out.The larval growth and survival were compared among hybrids and purebred strains at temperatures of 16,20,24,28 and 32℃;salinities of 15,20,25,30 and 35;and stocking densities of 0.5,1,2,4 and 8 larvae mL−1.Under different environments,the hybridization between two strains of C.gigas showed the heterosis of growth and survival.The mean shell height and survival rate of the two reciprocal crosses(OS,SO)were significantly higher than those of the two purebred strains(SS,OO)under all environ-mental conditions.In particular,OS showed greater heterosis than the purebred strains and SO progeny.The results showed that the productive traits of the‘Haida No.1’could be improved by crossing with the orange shell line.Meanwhile,the results from this study also indicated that hybridization between the two strains of C.gigas may be a promising way for breeding new variety with high survival rate.
基金The work was supported by the NZ Ministry of Foreign Aff air and Trade(MFAT)’s NZAID Programme.
文摘Silvicultural practices applied in managed forest plantations may help counteract the effects of climate change by influencing soil surface CO_(2)efflux(Fs).Understanding the effects of silvicultural practices on Fs will provide unbiased estimates of carbon fluxes and allow better silvicultural decisions for carbon sequestration.Therefore,we assessed how Fs differed seasonally across silvicultural practices(i.e.,stocking levels,clone,fertilization and weed control treatments)and evaluated the effects of soil temperature(Ts)and soil volumetric water content(θv)on Fs across these practices for a mid-rotation(14 year-old)Pinus radiata plantation in the Canterbury region of New Zealand.There were significant differences in Fs(p<0.05)over the four seasons,three levels of stocking,and five clones.The effects of fertilization and weed control applied 12 years previously on Fs were insignificant.Annual estimate of Fs(mean±1 standard deviation)from the study site was 22.7±7.1 t ha^(-1)a^(-1)in the form of CO_(2)(6.2±2.1 t ha^(-1)a^(-1)in the form of C).Fs values were consistently higher in plots with 1250 stems ha^(-1)compared to 2500 stems ha^(-1),which may be related to a strong soil resource limitation because of the close spacing in the latter plantation.Significant differences in Fs across clones suggest that variations in carbon partitioning might explain their growth performance.Silvicultural treatments influenced Fs response to soil temperature(p<0.05),resulting in models explaining 28-49%of the total variance in Fs.These findings provide insights into how silvicultural management decisions may impact Fs in mid-rotation radiata pine plantations,contributing towards developing more precise and unbiased plantation carbon budgets.
基金National Key Research and Development Program of China(No.2018YFC2000900)
文摘A series of self-designed and woven compression stockings were used in this pressure comparison experiment. In order to compare the differences of the garment pressure values exerted by the compression stockings with different structure parameters among three methods. The experiments were carried out with Flexi force sensors. The pressure value of nine pairs of compression stockings on five subjects and the model leg was collected, and the tensile force of the every section of these stockings was collected to calculate the pressure according to Laplace's equation. The data analysis results show that the pressure values of the compression stockings obtained by comparing the three methods have great differences in various testing methods. There is a significant correlation between processing parameters and stitch density(SD). The pressure design of the compression stockings should be based on the actual wearing of the pressure.
文摘Stocking of Lake Kinneret by exotic fish species (Mugilids: Mugil cephalus and Liza ramada) started in 1958. The rational stocking of Lake Kinneret with Mugilids was double functioned: To improve fishermen income and the water quality in the lake. Mugilids are chosen as introduction target because their market value is high, the fish cannot reproduce in the lake and fingerlings are low cost available. During 1960-2015, 56.2 million fingerlings were introduced into the lake approximately averaged one million per year of M. cephalus (MC) and L. ramada (LR). The study of the Mugilids food composition has indicated consumption of suspensoids, mostly detritial organic particles. Therefore no damage to water quality is suggested. The best fitness between recruitment to Dock on Side landings and stocking capacity was evaluated at 3 years interval. Differences were found between recruitments of MC and LR to commercial catches by individual averaged age and weight. The long term success of Mugilid introduction to Lake Kinneret is confirmed.
文摘Urochloa brizantha (synonymous of Brachiaria) is the most spread species of grass in the tropical world, primarily in regions with acid and low fertility soils. This study was conducted to investigate changes in the soil chemical properties of a Typical Acrudox submitted to a strategy of grazing with rotational stocking, liming and nitrogen fertilisation. Treatments involved combinations of two pre-grazing heights (25 and 35 cm) with two rates of nitrogen (50 and 200 kg·ha-1·year-1). All combinations received lime, P and K fertilization and an untreated control group was allocated according to a complete randomised block design, five replications. Soil sampling was done in layers of 0-5, 5-10, 10-20, 20-30 and 30-40 cm deep in pastures of U. brizantha Marandu (Palisade grass). The samples were analysed for pH, H+ + Al3+, soil organic matter (SOM), P, K+, Ca2+, Mg2+, exchangeable and calculated CEC, BS% and aluminium saturation. Liming and fertilisation improve the soil fertility. The highest organic matter contents were obtained for the 0-5 cm layer, with a nitrogen fertilisation of 200 kg·N·ha-1. The management practice for the pre-grazing height of 25 cm, regardless of the nitrogen, is the best strategy for soil quality and livestock production.
文摘A 10-week rearing trial was conducted in cages with average initial weight of 9.15 ± 0.2 g/fish and average initial length of 9.2 ± 0.02 cm/fish of meagre, Argyrosomus regius, to examine the effect of three stocking density on growth performances, production traits, feed utilization and body composition. Nine cages 24 m3 each (4 × 6 × 1.5 m, long, width and height) were stocked with either 1200, 3600 and 6000 fish for each cage to give a stocking rate of 50, 150, and 250 fish/m3 respectively and fish fed daily, slightly in excess of satiation to eliminate the possibility of food supply being a limiting factor to growth. The results revealed that, mean final weight (g/fish), gain in weight, SGR (%per day), feed conversion ratio, protein efficiency ratio and total feed intake (g/fish) were significantly (P ≤ 0.01) influenced. The best at the lowest stocking density, while, the total production and net production exhibited significantly the opposite trend. Harvest and production estimates increased with increasing stocking density. Fish body composition% of moisture, protein, fat and ash were significantly (P ≤ 0.01) influenced by stocking density. From the above results and the economic information of the study, it can be concluded that stocking density of 50 fish/m3 of meagre exhibited the highest net profit and would seem to be the most desirable density in the system studied.
文摘Chronic fatigue syndrome and myalgic encephalomyelitis (CFS/ME) are, amongst others, characterized by exercise intolerance, pain, post exertional malaise and orthostatic intolerance. It has been shown in venous disease and sport participation that compression stockings may improve exercise performance and reduce post exercise muscle soreness. Moreover, its use is advocated in orthostatic hypotension. Therefore, it was hypothesized that compression stockings may reduce symptomatology in CFS/ME patients. Methods: 100 patients used compression stockings class II for minimally 3 weeks and thereafter filled in a questionnaire, based on the Rand 36 physical activity questions (n = 9), whether compression stockings changed perceived symptoms or not. Moreover, 7 questions referring to prolonged standing and sitting, to recovery post exercise, muscle pain during or immediately post exercise, and to dizziness/light-headedness during or immediately post exercise, while standing and during prolonged sitting were added. Questions were scored as 1: able to perform activity much less while wearing the stockings, 2: perform activity somewhat less, 3: no perceived change in activity, 4: perform activity slightly better, 5: able to perform activity much better while wearing the stockings. Results: In patients able to answer the question, all mean scores per activity were significantly higher than 3, being no perceived change in activity while wearing the stockings. Subgroup analysis showed that patients with orthostatic intolerance reported higher effects than patients without orthostatic intolerance. Conclusion: This pilot study suggests that compression stockings may be useful to reduce symptomatology of physical activities in CFS/ME patients, especially in patients with orthostatic intolerance. Larger prospective studies with hard endpoints are warranted.
文摘Shrimps are recognized as the white gold of Bangladesh because it is the second largest export earning product after garments sector.The brown shrimp(M.monoceros)have high growth rates together with that they tolerate wide ranges of salinity and environmental parameters which makes them highly attractive for culture purposes.The purposes of this research were to assess the cultural performance and economic profitability of brown shrimp(Metapenaeus monoceros)in brackish water ponds.This research lasted from February to June 2020 under three different stocking densities such as 35,45 and 55 individuals/m2 in treatments T1,T2 and T3 at Bangladesh Fisheries Research Institute,Brackishwater Station,Paikgacha,Khulna.After 90 days culture periods the total production was 1703.32±144.48,2768.25±167.63 and 2535.03±253.52 kg/ha in T1,T2 and T3 respectively which was significantly higher(p<0.05)in T2 compared to T1 and T2.Benefit cost ratio(BCR)was 0.32,0.87 and 0.52 in T1,T2 and T3 respectively and found significantly higher(p<0.05)in T2 than T1 and T3.Both cultural performance and economic analysis imply that brown shrimp(M.monoceros)with a stocking density of 450000 individuals/ha might be environment conciliatory and economically enduring in coastal areas of Bangladesh.
文摘Fry stocking density can affect harvest metrics for fingerling walleye (Stizostedion vitreum) reared in drainable ponds, but few studies have examined these relationships with the use of elevated walleye fry stocking densities in lined ponds. Correlation and regression analyses were used to assess how a three-fold change in walleye fry stocking density (234,375 to 703,125 per hectare) relates to harvest metrics and length of the culture period, as well as the tradeoff experienced between walleye size (grams) and harvest density in 0.32-hectare lined ponds over a nine-year period at Blue Dog State Fish Hatchery, South Dakota. As fry stocking density increased, so did harvest metrics for both number (r = 0.85, P < 0.01) and yield (r = 0.81, P < 0.01). Length of the culture period varied between 24 and 35 days and was negatively related to stocking density (r = -0.66, P The linear relationship between harvest density and yield was highly correlated (r = 0.95, P < 0.01) with highest values measuring 617,625 walleye and 173 kilograms per hectare. Harvest density explained 61% of the variation in walleye size (P 0.01) and exhibited a decreasing curvilinear relationship such that continued increases in harvest density resulted in smaller reductions in fish size. Increasing fry stocking density from 234,375 to 703,125 per hectare in lined ponds coincided with increased rearing efficiencies for number and yield, as well as a reduced culture period. Minimal reduction in walleye size occurred once harvest density exceeded 300,000 per hectare.
基金supported by the National key R&D projects of China(2016YFD0500504)Agricultural innovation project of Hunan Province(2019TD01)
文摘This study was conducted to evaluate the effects of different stocking densities on growth performance,blood parameters,intestinal morphology and intestinal immunity of growing pigs.A total of288 male pigs(44.35±0.50 kg)were randomly assigned to groups with stocking densities of 2.46,1.23 and 0.82 m2/pig for a month.The results showed that there was no significant difference on growth performance among groups.Pigs in the stocking density of 0.82 m2/pig had the lowest backfat thickness and spleen weight index among groups(P<0.05).With increasing stocking density,the serum concentrations of blood urea nitrogen(BUN),transglutaminase(TGG),alkaline phosphatase(AKP)and immunoglobulin A(Ig A)were increased,and albumin(ALB),albumin-to-globulin ratio(ALB:GLO),insulin-like growth factor-1(IGF-1)and immunoglobulin(Ig M)were decreased(P<0.05),and cortisol tended to increase and glucose tended to decrease(0.05<P<0.1).Compared with the stocking density of 2.46 m2/pig,the ileal villus height and jejunal villus width decreased in stocking densities of 1.23 and 0.82 m2/pig(P<0.05).The duodenal villus height and ileal villus width in the stocking density of 0.82 m2/pig were the lowest among 3 groups(P<0.05).The content of immunoglobulin A in duodenum,jejunum and ileum mucosa increased along with increasing density(P<0.05).The contents of interleukin(IL)-2 in the spleen or liver and IL-10 in the spleen were higher in the stocking density of 0.82 m2/pig than in other 2 groups.These results showed that stocking density could affect the metabolism,intestinal morphology,and immunity of growing pigs and 1.23 m2/pig may be the suitable stocking density for the growing pigs in the present study.
基金supported by the Korean Institute of Planning and Evaluation for Technology in Food,Agriculture,Forestry and Fishery(IPET)through the Agri-Bio Industry Technology Development Program,funded by the Ministry of Agriculture,Food and Rural Affairs(316036-3)
文摘The present study was conducted to evaluate the effects of dietary gamma-aminobutyric acid(GABA)in broiler chickens raised in high stocking density(HSD)on performance and physiological responses.A total of 900 male broiler chicks(Ross 308)at 1 d old were assigned in a 2×2 factorial arrangement to 4 treatments(10 replicates per treatment)with stocking density,7.5 birds/m^2(low stocking density;LSD)or 15 birds/m^2(HSD),and dietary GABA,0 or 100 mg/kg.Chickens raised in HSD exhibited a decrease in body weight gain in all phases(P<0.05)and feed intake in starter and whole phases(P<0.01),and an increase in feed conversion ratio in the finisher phase(P<0.01)compared with LSD-raised chickens.However,dietary GABA did not affect growth performance nor interacted with stocking density on production variables.The HSD vs.LSD increased relative liver weight on d 35 whereas dietary GABA increased relative liver weight and decreased relative bursa weight on d 21.Both stocking density and dietary GABA affected yield and quality of breast and leg muscles.Dietary GABA increased(P<0.05)width of tibia on d 35 and interacted(P=0.054)with stocking density on breaking stocking density on d 35.The HSD vs.LSD group lowered(P<0.05)feather coverage scores.Significant interaction between stocking density and GABA on surface temperature of shank on d 21 was noted(P=0.024).Dietary GABA exhibited an opposite effect on the concentrations of cecal short-chain fatty acids depending on stocking density leading to a moderate to significant interaction.Stocking density decreased alpha-1-acid glycoprotein whereas dietary GABA decreased heterophil-to-lymphocyte ratio and corticosterone in blood or serum samples.Serum biochemical parameters were altered by stocking density or dietary GABA.It is concluded that dietary GABA alleviated stress indices including corticosterone and heterophilto-lymphocyte ratio,but failed to reverse stocking density-induced growth depression.
基金Research supported by National Natural Science Foundation of China(No.19531070)the Youth Project Foundation of Hubei Province Education Department(No.2002B00002)
文摘In this paper, a three species difFusive predator-prey modei with functional response and periodic stocking is studied, where all parameters are time depen-dent. By using new theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established.
基金supported by the Sustainable Forest Management Project with the Local Communities in Tigray,northern Ethiopia,which was funded by the Norwegian Agency for Development Cooperation(NORAD)under the Norwegian Programme for Capacity Development in Higher EducationResearch for Development(NORHED)Programme(ETH 13/0018)+4 种基金the Ecological Organic Agriculture Project,Mekelle University,Ethiopiathe Institute of International Education-Scholars Rescue Fund(IIE-SRF)Norwegian University of Life Sciences(NMBU)Faculty of Environmental Sciences and Natural Resource Management(MINA)NORGLOBAL 2 Project in Ethiopia(303600)for supporting the research。
文摘Proposed agroforestry options should begin with the species that farmers are most familiar with,which would be the native multipurpose trees that have evolved under smallholder farms and socioeconomic conditions.The African birch(Anogeissus leiocarpa(DC.)Guill.&Perr.)and pink jacaranda(Stereospermum kunthianum Cham.)trees are the dominant species in the agroforestry parkland system in the drylands of Tigray,Ethiopia.Smallholder farmers highly value these trees for their multifunctional uses including timber,firewood,charcoal,medicine,etc.These trees also could improve soil fertility.However,the amount of soil physical and chemical properties enhanced by the two species must be determined to maintain the sustainable conservation of the species in the parklands and to scale up to similar agroecological systems.Hence,we selected twelve isolated trees,six from each species that had similar dendrometric characteristics and were growing in similar environmental conditions.We divided the canopy cover of each tree into three radial distances:mid-canopy,canopy edge,and canopy gap(control).At each distance,we took soil samples from three different depths.We collected 216 soil samples(half disturbed and the other half undisturbed)from each canopy position and soil depth.Bulk density(BD),soil moisture content(SMC),soil organic carbon(SOC),total nitrogen(TN),available phosphorus(AP),available potassium(AK),p H,electrical conductivity(EC),and cation exchange capacity(CEC)were analysed.Results revealed that soil physical and chemical properties significantly improved except for soil texture and EC under both species,CEC under A.leiocarpus,and soil p H under S.kunthianum,all the studied soils were improved under both species canopy as compared with canopy gap.SMC,TN,AP,and AK under canopy of these trees were respectively 24.1%,11.1%,55.0%,and 9.3% higher than those soils under control.The two parkland agroforestry species significantly enhanced soil fertility near the canopy of topsoil through improving soil physical and chemical properties.These two species were recommended in the drylands with similar agro-ecological systems.
基金funded by the Major Humanities and Social Sciences Research Projects in Zhejiang higher education institutions,grant number 2023QN082,awarded to Cheng ZhaoThe National Natural Science Foundation of China also provided funding,grant number 61902349,awarded to Cheng Zhao.
文摘The present study examines the impact of short-term public opinion sentiment on the secondary market,with a focus on the potential for such sentiment to cause dramatic stock price fluctuations and increase investment risk.The quantification of investment sentiment indicators and the persistent analysis of their impact has been a complex and significant area of research.In this paper,a structured multi-head attention stock index prediction method based adaptive public opinion sentiment vector is proposed.The proposedmethod utilizes an innovative approach to transform numerous investor comments on social platforms over time into public opinion sentiment vectors expressing complex sentiments.It then analyzes the continuous impact of these vectors on the market through the use of aggregating techniques and public opinion data via a structured multi-head attention mechanism.The experimental results demonstrate that the public opinion sentiment vector can provide more comprehensive feedback on market sentiment than traditional sentiment polarity analysis.Furthermore,the multi-head attention mechanism is shown to improve prediction accuracy through attention convergence on each type of input information separately.Themean absolute percentage error(MAPE)of the proposedmethod is 0.463%,a reduction of 0.294% compared to the benchmark attention algorithm.Additionally,the market backtesting results indicate that the return was 24.560%,an improvement of 8.202% compared to the benchmark algorithm.These results suggest that themarket trading strategy based on thismethod has the potential to improve trading profits.
