Improving the efficiency and production of grazing ruminants to support food and fiber production,while reducing the environmental footprint and meeting the welfare needs of the animals,is important for sustainable li...Improving the efficiency and production of grazing ruminants to support food and fiber production,while reducing the environmental footprint and meeting the welfare needs of the animals,is important for sustainable livestock production systems.Development of new technologies that can improve the efficiency of nitrogen(N)utilization in ruminants,and that are effective and safe,has important implications for ruminant livestock production.N-carbomoylglutamate(NCG)is a functional micronutrient that stimulates endogenous synthesis of arginine,which can improve survival,growth,lactation,reproductive performance,and feed efficiency in mammals.There is a growing body of evidence to support the potential of dietary NCG supplementation to improve the productive capacity and N utilization efficiency of ruminants.This review summarizes the current literature on the effects of dietary supplementation with NCG in ruminants and impacts on production and potential to reduce the environmental footprint of farmed ruminant livestock.The current literature highlights the potential for commercial application in ruminant livestock to improve productivity and N utilization efficiency.展开更多
Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating this.In this study,we investigated for first...Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating this.In this study,we investigated for first time the genetic variation within a candidate‘grazing gene',the glutamate metabotropic receptor 5 gene(GRM5),and tested associations between variation in that gene and variation in grazing personality behaviours(GP-behaviours)displayed by free-ranging cows during winter grazing in the steep and rugged rangelands of New Zealand.Mature beef cows(n=303,from 3 to 10 years of age)were tracked with global positioning system(GPS)and,with 5-minutes(min)relocation frequency,various GP-behaviours were calculated.These included horizontal and vertical distances travelled,mean elevation,elevation range,elevation gain,slope,home range and movement tortuosity,variously calculated using daily relocation trajectories with repeated measurements(i.e.,7 to 24 days(d))and satellite-derived digital elevation models(DEM).The different GP-behaviours were fitted into mixed models to ascertain their associations with variant sequences and genotypes of GRM5.Results:We discovered three GRM5 variants(A,B and C)and identified the six possible genotypes in the cattle studied.The mixed models revealed that A was significantly associated with elevation range,home range and movement tortuosity.Similarly,GRM5 genotypes were associated(P<0.05)to home range and movement tortuosity,while trends suggesting association(P<0.1)were also revealed for elevation range and horizontal distance travelled.Most GP-behaviour models were improved by correcting for cow age-class as a fixed factor.The analysis of GP-behaviours averaged per cow age-class suggests that grazing personality is fully established as beef cows reached 4 years of age.Home range and movement tortuosity were not only associated with GRM5 variation,but also negatively correlated with each other(r=-0.27,P<0.001).Conclusions:There seems to be a genetically determined trade-off between home range and movement tortuosity that may be useful in beef cattle breeding programmes aiming to improve the grazing distribution and utilisation of steep and rugged rangelands.展开更多
AIM:To investigate the effect of transgenic expression of kallistatin(Kal) on carbon tetrachloride(CCl 4)induced liver injury by intramuscular(im) electrotransfer of a Kal-encoding plasmid formulated with poly-Lglutam...AIM:To investigate the effect of transgenic expression of kallistatin(Kal) on carbon tetrachloride(CCl 4)induced liver injury by intramuscular(im) electrotransfer of a Kal-encoding plasmid formulated with poly-Lglutamate(PLG).METHODS:The pKal plasmid encoding Kal gene was formulated with PLG and electrotransferred into mice skeletal muscle before the administration of CCl 4.The expression level of Kal was measured.The serum biomarker levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),malonyldialdehyde(MDA),and tumor necrosis factor(TNF)-α were monitored.The extent of CCl 4-induced liver injury was analyzed histopathologically.RESULTS:The transgene of Kal was sufficiently expressed after an im injection of plasmid formulated with PLG followed by electroporation.In the Kal gene-transferred mice,protection against CCl 4-induced liver injury was reflected by significantly decreased serum ALT,AST,MDA and TNF-α levels compared to those in control mice(P < 0.01 to 0.05 in a dose-dependent manner).Histological observations also revealed that hepatocyte necrosis,hemorrhage,vacuolar change and hydropic degeneration were apparent in mice after CCl 4 administration.In contrast,the damage was markedly attenuated in the Kal gene-transferred mice.The expression of hepatic fibrogenesis marker transforming growth factor-β1 was also reduced in the pKal transferred mice.CONCLUSION:Intramuscular electrotransfer of plasmid pKal which was formulated with PLG significantly alleviated the CCl 4-induced oxidative stress and inflammatory response,and reduced the liver damage in a mouse model.展开更多
Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of applications.In this paper,we propose a feature-based vector model and a novel weighting alg...Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of applications.In this paper,we propose a feature-based vector model and a novel weighting algorithm for sentiment analysis of Chinese product reviews.Specifically,an opinionated document is modeled by a set of feature-based vectors and corresponding weights.Different from previous work,our model considers modifying relationships between words and contains rich sentiment strength descriptions which are represented by adverbs of degree and punctuations.Dependency parsing is applied to construct the feature vectors.A novel feature weighting algorithm is proposed for supervised sentiment classification based on rich sentiment strength related information.The experimental results demonstrate the effectiveness of the proposed method compared with a state of the art method using term level weighting algorithms.展开更多
This study investigated the impacts of the degree of unsaturation (unsaturity) of long-chain fatty acids on volatile fatty acid (VFA) profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, i...This study investigated the impacts of the degree of unsaturation (unsaturity) of long-chain fatty acids on volatile fatty acid (VFA) profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, including stearic acid (C18:0, control group), oleic acid (C18:1, n-9), linoleic acid (C18:2, n-6), a-linolenic acid (C18:3, n-3), arachidonic acid (C20:4, n-6) and eicosapentaenoic acid (C20:5, n-3), were tested. Rumen fluid from three goats fitted with ruminal fistulae was used as inoculum and the inclusion rate of long-chain fatty acid was at 3% (w/w) of substrate. Samples were taken for VFA analysis at 0, 3, 6, 9, 12, 18 and 24 h of incubation, respectively. The analysis showed that there were significant differences in the total VFA among treatments, sampling time points, and treatment×time point interactions (P〈0.01). a-Linolenic acid had the highest total VFA (P〈0.01) among different long-chain fatty acids tested. The molar proportion of acetate in total VFA significantly differed among treatments (P〈0.01) and sampling time points (P〈0.01), but not treatment×time point interactions (P〉0.05). In contrast, the molar proportion of propionate did not differ among treatments during the whole incubation (P〉0.05). However, for butyrate molar proportions, significant differences were found not only among sampling time points but also among treatments and treatment×time point interactions (P〈0.01), with eicosapentaenoic acid having the highest value (P〈0.01). Additionally, no statistically significant differences were found in the acetate to propionate ratios among treatments groups (P〉0.05), even the treatments stearic acid and a-linolenic acid were numerically higher than the others. The inclusion of 3% long-chain unsaturated fatty acids differing in the degree of unsaturation brought out a significant quadratic regression relation between the total VFA concentration and the double bond number of fatty acid. In conclusion, the a-linolenic acid with 3 double bonds appeared better for improving rumen microbial fermentation and the total VFA concentration.展开更多
Maternal photoperiodic response is a key factor that affects offspring diapause in migratory locust,Locusta migratoria L.(Orthoptera:Acridoidea).Although many aspects of insect diapause have been studied,little is kno...Maternal photoperiodic response is a key factor that affects offspring diapause in migratory locust,Locusta migratoria L.(Orthoptera:Acridoidea).Although many aspects of insect diapause have been studied,little is known about the molecular mechanisms of maternal photoperiodic response that influence diapause regulation.To gain insight into the possible mechanisms of maternal photoperiod influence on diapause regulation,proteomics data by label-free quantification analysis were generated from non-diapause and diapause eggs.A total of 175 proteins were differentially expressed between diapause and non-diapause eggs.Among them,24 proteins were upregulated,and 151 proteins were downregulated.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichments were performed on all differentially expressed proteins(DEPs)and showed that peroxisome,insect hormone biosynthesis,and longevity regulating pathway may be related to diapause of migratory locust.Furthermore,we used qRT-PCR to verify some results of the proteomic analysis.Proteins such as hexamerin-like protein 4,juvenile hormone epoxide hydrolase 1(JHEH1),cytochrome P450 and heat shock protein(HSP)20.7 were predicted to be involved in diapause.This study provides an important reference for future research that will explore the mechanisms of diapause induced by maternal effects in migratory locust.展开更多
The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degrad...The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P<0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P>0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P<0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P>0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.展开更多
Growth and differentiation factor-11 (GDF-11) is a secreted protein that is closely related to myostatin, a known inhibitor of skeletal muscle development. The role of GDF-11 in regulating skeletal muscle growth remai...Growth and differentiation factor-11 (GDF-11) is a secreted protein that is closely related to myostatin, a known inhibitor of skeletal muscle development. The role of GDF-11 in regulating skeletal muscle growth remains unclear and the pattern of expression during post-natal growth has not been reported. Therefore, we sought to determine the expression of GDF-11 during post-natal growth and its effect on myoblast proliferation and differentiation. We collected gastrocnemius muscles from male and female mice at 2, 3, 4, 6, 12, 20 and 32 weeks of age (n = 6 per sex and age). In addition, gastrocnemius muscles were col- lected from male wild-type and myostatin knockout mice at 4, 6, 12 and 20 weeks of age (n = 6 per age and genotype). RNA was extracted and reverse tran- scribed. Northern analysis identified an expected 4.4 kb mRNA transcript for GDF-11 in gastrocnemius muscles of mice. The concentration of GDF-11 mRNA, as determined by quantitative PCR, was increased in gastrocnemius muscles from 2 to 6 weeks—a period of rapid postnatal muscle growth—and remained higher in male than female mice from 4 to 20 weeks of age (P gastrocnemius muscles of myostatin knockout compared with wild-type mice (P < 0.05), which may suggest a compensatory mecha- nism for the lack of myostatin. In support, recombi- nant GDF-11 inhibited differentiation of C2C12 mur- ine myoblasts and those isolated from myostatin knockout and wild-type mice (P < 0.05). Inhibited dif-ferentiation of C2C12 myoblasts was associated with decreased mRNA expression of early and late mo- lecular markers of differentiation (MyoD, myogenin, IGF-II, desmin and MyHC, P < 0.05). Our results suggest that GDF-11 regulates growth of skeletal muscles by inhibiting myoblast differentiation in an autocrine/paracrine manner and, perhaps, also plays a role in regulating sexually dimorphic growth.展开更多
AIM: To investigate the role that single nucleotide polymorphisms (SNPs) in the promoter of the tumour necrosis factor-alpha (TNF-α) gene play in the risk of inflammatory bowel diseases (IBDs) in a New Zealand popula...AIM: To investigate the role that single nucleotide polymorphisms (SNPs) in the promoter of the tumour necrosis factor-alpha (TNF-α) gene play in the risk of inflammatory bowel diseases (IBDs) in a New Zealand population, in the context of international studies. METHODS: DNA samples from 388 patients with Crohn's disease (CD), 405 ulcerative colitis (UC), 27 indeterminate colitis (IC) and 201 randomly selected controls, from Canterbury, New Zealand were screened for 3 common polymorphisms in the TNF-α receptor: -238 G→A, -308 G→A and -857C→T, using a TaqmanR assay. A meta-analysis was performed on the data obtained on these polymorphisms combined with that from other published studies. RESULTS: Individuals carrying the -308 G/A allele had a significantly (OR = 1.91, χ2 = 17.36, P < 0.0001) increased risk of pancolitis, and a 1.57-fold increased risk (OR = 1.57, χ2 = 4.34, P = 0.037) of requiring a bowel resection in UC. Carrying the -857 C/T variant decreased the risk of ileocolonic CD (OR = 0.56, χ2 =4.32, P = 0.037), and the need for a bowel resection (OR = 0.59, χ2 = 4.85, P = 0.028). The risk of UC was reduced in individuals who were smokers at diagnosis, (OR = 0.48, χ2 = 4.86, P = 0.028). CONCLUSION: TNF-α is a key cytokine known to play a role in inflammatory response, and the locus for the gene is found in the IBD3 region on chromosome 6p21, known to be associated with an increased risk for IBD. The -308 G/A SNP in the TNF-α promoter is functional, and may account in part for the increased UC risk associated with the IBD3 genomic region. The -857 C/T SNP may decrease IBD risk in certain groups. Pharmaco- or nutrigenomic approaches may be desir- able for individuals with such affected genotypes.展开更多
响应到稻田的脲申请的氨挥发损失,氮利用效率,和米饭收益在 Wangzhuang 镇上被调查, Changshu 城市,江苏省,中国。N 化肥处理,适用在三倍,是 0 (控制) , 100, 200, 300,或 350 kg N 哈 ? 1。在脲被用于地面水以后,一个连续...响应到稻田的脲申请的氨挥发损失,氮利用效率,和米饭收益在 Wangzhuang 镇上被调查, Changshu 城市,江苏省,中国。N 化肥处理,适用在三倍,是 0 (控制) , 100, 200, 300,或 350 kg N 哈 ? 1。在脲被用于地面水以后,一个连续气流包围方法被用来在稻田测量氨挥发。通过氨挥发的全部的 N 损失通常与 N 申请率,和申请评估的二更高的 N 增加了(300 和 350 kg N 哈 ? 1 ) 证明 N 的更高的比率通过氨挥发输了到应用 N。由在全部米饭期间,生长上演的氨挥发的全部的氨损失从 9.0% ~ 16.7% 应用 N 。增加申请率通常减少了在到在植物的 N 的种子的 N 的比率。为所有 N 处理,氮肥利用效率从 30.9% ~ 45.9%。有最高的 N 率的剩余 N 导致了米饭植物,氮肥利用的减少的率,和减少的米饭收益的住宿。从这个实验计算,最节俭的 N 化肥申请率是 227 kg 哈 ? 1 为在泰胡·莱克区域的水稻土的类型。然而,推荐适当 N 化肥申请率以便植物生长被提高,氨损失被减少能改进大米的 N 利用效率。展开更多
A system to control the release of phosphate in water was successfully established, based on solubility product of [Ca^2+] and [PO4^3-] using tricalcium phosphate as P source in the hydroponic solution, and adding Ca...A system to control the release of phosphate in water was successfully established, based on solubility product of [Ca^2+] and [PO4^3-] using tricalcium phosphate as P source in the hydroponic solution, and adding CaCl2 for supplementing extra Ca^2+. The system, similar to soil solutions, was a P nutrient buffer solution with very low bioavailable P. The buffer solution induced the roots of both monocotyledon and dicotyledon species to grow abundant root hairs, 3 mm in maximum length. The monocotyledons were corn (Zea mays L.) (var. Yellow Rose), wheat (Triticum aestivum L.) (var. Yanzhong 144), Triticale secale L. (vat. Jingsong 5), and ryegrass (Lolium rigidum L.) (var. Ruanni), and the dicotyledons were Arabidopsis thaliana L. (var. Columbia), white clover (Trifolium repens) (var. Kopu), Lotus (Lotus peduncucatus Cav. Luliginosus Schkuhr) (var. Grasslands Maku). For these species we proved that the root environment controls the induction of root hair formation. However, the hydroponic buffer solution failed to induce root hairs on the roots of onion (Allium cepa L.). Other investigators have concluded that corn does not form root hairs in hydroponics, but abundant long root hairs on corn were induced by this buffer system. The roots with abundant long root hairs are called "hedgehog roots" because they have hairs everywhere just like a hedgehog.展开更多
The aphid quantity ratio(AQR) is defined as the number of aphids on each cultivar divided by the number of aphids on all cultivars. AQR is based on the correlation between aphid populations and their host plants and...The aphid quantity ratio(AQR) is defined as the number of aphids on each cultivar divided by the number of aphids on all cultivars. AQR is based on the correlation between aphid populations and their host plants and is an important tool that has been utilized in evaluating Medicago sativa(alfalfa) cultivar resistance to aphids. However, assessment of alfalfa resistance to aphids can be confused by the presence of aphid predators, causing the assessment of plant resistance to aphids to be based on incorrect aphid population data. To refine the AQR and account for the effect of predators on aphid population assessments, we introduced a parameter ‘α', corresponding to the predator quantity ratio, and used αAQR as the ratio to quantify aphid populations. Populations of both aphids(4 species) and their predators(12 species) occurring in 28 M. sativa cultivars were sampled over two years at a research station near Cangzhou, Hebei Province, China. Results showed that the most suitable evaluation period was from May to June, as the aphid population was stable during this period. Compared with the AQR method, the predator population numbers based on the αAQR had a significant inverse relationship with aphid population numbers and the 28 cultivars were clustered into three classes: the resistant class, tolerant class, and susceptible class. In addition, 17 cultivars were reassigned when evaluated using αAQR. All numerical values calculated by αAQR were displayed as a Gaussian distribution, which showed that the 28 cultivars could be clustered into nine groups using a median value(±SE) of 1±0.1. Hence, ongoing alfalfa breeding trials will be assessed using the αAQR to establish a robust system that includes agronomic performance parameters in order to generalize the new method for further studies.展开更多
Background: Despite its variety of potential applications, the wide implementation of infrared technology in cattle production faces technical, environmental and biological challenges similar to other indicators of m...Background: Despite its variety of potential applications, the wide implementation of infrared technology in cattle production faces technical, environmental and biological challenges similar to other indicators of metabolic state. Nine trials, divided into three classes (technological, environmental and biological factors) were conducted to illustrate the influence of these factors on body surface temperature assessed through infrared imaging. Results: Evaluation of technological factors indicated the following: measurements of body temperatures were strongly repeatable when taken within ]0 s; appropriateness of differing infrared camera technologies was influenced by distance to the target; and results were consistent when analysis of thermographs was compared between judges. Evaluation of environmental factors illustrated that wind and debris caused decreases in body surface temperatures without affecting metabolic rate; additionally, body surface temperature increased due to sunlight but returned to baseline values within minutes of shade exposure. Examination/investigation/exploration of animal factors demonstrated that exercise caused an increase in body surface temperature and metabolic rate. Administration of sedative and anti-sedative caused changes on body surface temperature and metabolic rate, and during late pregnancy a foetal thermal imprint was visible through abdominal infrared imaging. Conclusion: The above factors should be considered in order to standardize operational procedures for taking thermographs, thereby optimizing the use of such technology in cattle operations.展开更多
Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value ...Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value or condition of these materials. This study was designed to investigate hydrothermal damage in wool proteins at the molecular level. The effect of hydrothermal damage on Type I and II intermediate filament proteins (keratins) extracted from wool was characterised using advanced quantitative techniques based on isobaric iTRAQ labelling and mass spectrometry. Many native peptides were observed to be degraded and modified. Amongst these, twenty keratin peptides were observed to consistently degrade during hydrothermal exposure. These peptides acted as molecular markers of damage – specific indicators of the extent of heat-induced protein damage. This technology will be of value in assessing the severity of damage imparted after high temperature exposure of protein-based animal fibres such as wool and cashmere during processes such as dyeing and carbonising, or even after high temperature human hair treatments. The identification of molecular damage markers identified within wool and other materials provides a new route to sensitive and specific evaluation of the effects of protein deterioration. It is anticipated that the utilisation of such markers will facilitate the development of targeted approaches to minimising processing damage to high-value fibres and protein-based biomaterials.展开更多
Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at...Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at regular intervals.As these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive outcomes.The treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial arrangement.We randomly assigned 150 cows to one of two far-off treatments.During late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of lactation.Within each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving requirements.Results:Uterine health improved(i.e.polymorphonucleated(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed group.The reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up period.The postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed intakes(Feed120);yet,close-up dry matter intake had little effect on conception and pregnancy rates for the Controlfed group.Conclusions:The far-off feeding strategies increased early reproductive outcomes at 3 weeks of mating.Additionally,the interaction between far-off and close-up feeding strategies resulted in high six-week pregnancy rate with a slight restriction during the close-up period but only in the far-off Overfed group.Thus,our hypothesis is supported under these conditions.展开更多
Background: Cytoplasmic injection of exogenous DNA into zygotes is a promising technique to generate transgenic livestock. However, it is still relatively inefficient and has not yet been demonstrated to work in buff...Background: Cytoplasmic injection of exogenous DNA into zygotes is a promising technique to generate transgenic livestock. However, it is still relatively inefficient and has not yet been demonstrated to work in buffalo. We sought to improve two key technical parameters of the procedure, namely i) how much linear DNA to inject and ii) when to inject it. For this, we introduced a constitutively expressed enhanced green fluorescent protein (EGFP) plasmid into buffalo zygotes. Results: First, we found that the proportion of EGFP-expressing blastocysts derived from zygotes injected with 20 or 50 ng/pL DNA was significantly higher than from those injected with 5 pg/mL. However, 50 ng/pL exogenous DNA compromised blastocyst development compared to non-injected IVF controls. Therefore the highest net yield of EGFP-positive blastocysts was achieved at 20 ng/pL DNA. Second, zygotes injected early (7-8 h post-insemination [hpi]) developed better than those injected at mid (12-13 hpi) or late (18-19 hpi) time points. Blastocysts derived from early injections were also more frequently EGFP-positive. As a consequence, the net yield of EGFP-expressing blastocysts was more than doubled using early vs late injections (16.4 % vs 7.7 %). With respect to blastocyst quality, we found no significant difference in cell numbers of EGFP-positive blastocysts vs non-injected blastocysts. Following embryo transfer of six EGFP-positive blastocysts into four recipient animals, two viable buffalo calves were born. Biopsied ear tissues from both buffalo calves were analyzed for transgene presence and expression by Southern blot, PCR and confocal laser scanning microscopy, respectively. This confirmed that both calves were transgenic. Conclusions: Our cytoplasmic injection protocol improved generation of transgenic embryos and resulted in the first transgenic buffalo calves produced by this method.展开更多
Fungal Epichloëendophytes form symbiotic associations with many temperate grasses,such as Lolium and Festuca,giving their host grasses an ecological advantage.The importance of specific Epichloëendophytes in...Fungal Epichloëendophytes form symbiotic associations with many temperate grasses,such as Lolium and Festuca,giving their host grasses an ecological advantage.The importance of specific Epichloëendophytes in providing varying levels of protection against invertebrate pests has been well documented.Similarly,but with fewer studies,the benefits of Epichloëto host grasses in drought events has been shown.Endophyte-infected grasses show an improved persistence against herbivore insect attack as well as resilience under drought.However,there are relatively few studies that investigate the interaction between drought and insect pressure,and yet it is these combined pressures that can prove detrimental for a ryegrass or fescue crop.This review examines the current state of knowledge on the effects of Epichloëon the interactions of insects and drought in temperate grasses.展开更多
基金funded by Ballance AgriNutrients and the Ministry of Primary Industries“Future Ready Farms-Together,creating a lower emissions Future”Sustainable Farming Futures Fund program.
文摘Improving the efficiency and production of grazing ruminants to support food and fiber production,while reducing the environmental footprint and meeting the welfare needs of the animals,is important for sustainable livestock production systems.Development of new technologies that can improve the efficiency of nitrogen(N)utilization in ruminants,and that are effective and safe,has important implications for ruminant livestock production.N-carbomoylglutamate(NCG)is a functional micronutrient that stimulates endogenous synthesis of arginine,which can improve survival,growth,lactation,reproductive performance,and feed efficiency in mammals.There is a growing body of evidence to support the potential of dietary NCG supplementation to improve the productive capacity and N utilization efficiency of ruminants.This review summarizes the current literature on the effects of dietary supplementation with NCG in ruminants and impacts on production and potential to reduce the environmental footprint of farmed ruminant livestock.The current literature highlights the potential for commercial application in ruminant livestock to improve productivity and N utilization efficiency.
基金CAMG was funded with a Lincoln University Ph D scholarship(Lincoln University Centennial Trust,New Zealand)with research funding from the New Zealand Hereford Association(NZHA)the Hellaby Grasslands Trust。
文摘Background:The grazing behaviour of herbivores and their grazing personalities might in part be determined genetically,but there are few studies in beef cattle illustrating this.In this study,we investigated for first time the genetic variation within a candidate‘grazing gene',the glutamate metabotropic receptor 5 gene(GRM5),and tested associations between variation in that gene and variation in grazing personality behaviours(GP-behaviours)displayed by free-ranging cows during winter grazing in the steep and rugged rangelands of New Zealand.Mature beef cows(n=303,from 3 to 10 years of age)were tracked with global positioning system(GPS)and,with 5-minutes(min)relocation frequency,various GP-behaviours were calculated.These included horizontal and vertical distances travelled,mean elevation,elevation range,elevation gain,slope,home range and movement tortuosity,variously calculated using daily relocation trajectories with repeated measurements(i.e.,7 to 24 days(d))and satellite-derived digital elevation models(DEM).The different GP-behaviours were fitted into mixed models to ascertain their associations with variant sequences and genotypes of GRM5.Results:We discovered three GRM5 variants(A,B and C)and identified the six possible genotypes in the cattle studied.The mixed models revealed that A was significantly associated with elevation range,home range and movement tortuosity.Similarly,GRM5 genotypes were associated(P<0.05)to home range and movement tortuosity,while trends suggesting association(P<0.1)were also revealed for elevation range and horizontal distance travelled.Most GP-behaviour models were improved by correcting for cow age-class as a fixed factor.The analysis of GP-behaviours averaged per cow age-class suggests that grazing personality is fully established as beef cows reached 4 years of age.Home range and movement tortuosity were not only associated with GRM5 variation,but also negatively correlated with each other(r=-0.27,P<0.001).Conclusions:There seems to be a genetically determined trade-off between home range and movement tortuosity that may be useful in beef cattle breeding programmes aiming to improve the grazing distribution and utilisation of steep and rugged rangelands.
基金新西兰恒天然-中国科学院国际合作项目International Collaborative Research on Dairy Farm Waste application to land supported by Fonterra(Beijing)Farm Management Consulting Co.Ltd
基金Supported by The State High Technology Research and Development Program of China (863 Program),No.2008AA02Z135the Important National Science and Technology Specific Projects,No.2009ZX09103-643the Natural Science Foundation of China,No.30973591
文摘AIM:To investigate the effect of transgenic expression of kallistatin(Kal) on carbon tetrachloride(CCl 4)induced liver injury by intramuscular(im) electrotransfer of a Kal-encoding plasmid formulated with poly-Lglutamate(PLG).METHODS:The pKal plasmid encoding Kal gene was formulated with PLG and electrotransferred into mice skeletal muscle before the administration of CCl 4.The expression level of Kal was measured.The serum biomarker levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),malonyldialdehyde(MDA),and tumor necrosis factor(TNF)-α were monitored.The extent of CCl 4-induced liver injury was analyzed histopathologically.RESULTS:The transgene of Kal was sufficiently expressed after an im injection of plasmid formulated with PLG followed by electroporation.In the Kal gene-transferred mice,protection against CCl 4-induced liver injury was reflected by significantly decreased serum ALT,AST,MDA and TNF-α levels compared to those in control mice(P < 0.01 to 0.05 in a dose-dependent manner).Histological observations also revealed that hepatocyte necrosis,hemorrhage,vacuolar change and hydropic degeneration were apparent in mice after CCl 4 administration.In contrast,the damage was markedly attenuated in the Kal gene-transferred mice.The expression of hepatic fibrogenesis marker transforming growth factor-β1 was also reduced in the pKal transferred mice.CONCLUSION:Intramuscular electrotransfer of plasmid pKal which was formulated with PLG significantly alleviated the CCl 4-induced oxidative stress and inflammatory response,and reduced the liver damage in a mouse model.
基金This work was supported in part by National Natural Science Foundation of China under Grants No.60970052,the Beijing Natural Science Foundation under Grants No.4133084,the Beijing Educational Committee Science and Technology Development Planned under Grants No.KM201410028017 and the Beijing Key Disciplines of Computer Application Technology
文摘Sentiment analysis of online reviews and other user generated content is an important research problem for its wide range of applications.In this paper,we propose a feature-based vector model and a novel weighting algorithm for sentiment analysis of Chinese product reviews.Specifically,an opinionated document is modeled by a set of feature-based vectors and corresponding weights.Different from previous work,our model considers modifying relationships between words and contains rich sentiment strength descriptions which are represented by adverbs of degree and punctuations.Dependency parsing is applied to construct the feature vectors.A novel feature weighting algorithm is proposed for supervised sentiment classification based on rich sentiment strength related information.The experimental results demonstrate the effectiveness of the proposed method compared with a state of the art method using term level weighting algorithms.
基金financially supported by the Graduate Student Innovation Project of Jiangsu Province,China (KYLX15_1377)the Natural Science Foundation of Jiangsu Province,China (BK20151312)the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD),China
文摘This study investigated the impacts of the degree of unsaturation (unsaturity) of long-chain fatty acids on volatile fatty acid (VFA) profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, including stearic acid (C18:0, control group), oleic acid (C18:1, n-9), linoleic acid (C18:2, n-6), a-linolenic acid (C18:3, n-3), arachidonic acid (C20:4, n-6) and eicosapentaenoic acid (C20:5, n-3), were tested. Rumen fluid from three goats fitted with ruminal fistulae was used as inoculum and the inclusion rate of long-chain fatty acid was at 3% (w/w) of substrate. Samples were taken for VFA analysis at 0, 3, 6, 9, 12, 18 and 24 h of incubation, respectively. The analysis showed that there were significant differences in the total VFA among treatments, sampling time points, and treatment×time point interactions (P〈0.01). a-Linolenic acid had the highest total VFA (P〈0.01) among different long-chain fatty acids tested. The molar proportion of acetate in total VFA significantly differed among treatments (P〈0.01) and sampling time points (P〈0.01), but not treatment×time point interactions (P〉0.05). In contrast, the molar proportion of propionate did not differ among treatments during the whole incubation (P〉0.05). However, for butyrate molar proportions, significant differences were found not only among sampling time points but also among treatments and treatment×time point interactions (P〈0.01), with eicosapentaenoic acid having the highest value (P〈0.01). Additionally, no statistically significant differences were found in the acetate to propionate ratios among treatments groups (P〉0.05), even the treatments stearic acid and a-linolenic acid were numerically higher than the others. The inclusion of 3% long-chain unsaturated fatty acids differing in the degree of unsaturation brought out a significant quadratic regression relation between the total VFA concentration and the double bond number of fatty acid. In conclusion, the a-linolenic acid with 3 double bonds appeared better for improving rumen microbial fermentation and the total VFA concentration.
基金funded by the earmarked fund of China Agriculture Research System (CARS-34-07)the National Natural Science Foundation of China (31672485)
文摘Maternal photoperiodic response is a key factor that affects offspring diapause in migratory locust,Locusta migratoria L.(Orthoptera:Acridoidea).Although many aspects of insect diapause have been studied,little is known about the molecular mechanisms of maternal photoperiodic response that influence diapause regulation.To gain insight into the possible mechanisms of maternal photoperiod influence on diapause regulation,proteomics data by label-free quantification analysis were generated from non-diapause and diapause eggs.A total of 175 proteins were differentially expressed between diapause and non-diapause eggs.Among them,24 proteins were upregulated,and 151 proteins were downregulated.Gene Ontology(GO)analysis and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichments were performed on all differentially expressed proteins(DEPs)and showed that peroxisome,insect hormone biosynthesis,and longevity regulating pathway may be related to diapause of migratory locust.Furthermore,we used qRT-PCR to verify some results of the proteomic analysis.Proteins such as hexamerin-like protein 4,juvenile hormone epoxide hydrolase 1(JHEH1),cytochrome P450 and heat shock protein(HSP)20.7 were predicted to be involved in diapause.This study provides an important reference for future research that will explore the mechanisms of diapause induced by maternal effects in migratory locust.
基金Lorestan University,Iran,for its financial support。
文摘The digestive tract of termite(Microcerotermes diversus) contains a variety of lignocellulose-degrading bacteria with exocellulases enzyme activity, not found in the rumen, which could potentially improve fiber degradation in the rumen. The objectives of the current study were to determine the effect of inoculation of rumen fluid(RF) with three species of bacteria isolated from termite digestive tract, Bacillus licheniformis, Ochrobactrum intermedium, and Microbacterium paludicola, on in vitro gas production(IVGP), fermentation parameters, nutrient disappearance, microbial populations, and hydrolytic enzyme activities with fibrous wheat straw(WS) and date leaf(DL) as incubation substrate. Inoculation of RF with either of three termite bacteria increased(P<0.05) ammonia-N concentration compared with the control group(free of termite gut bacteria). Termite bacteria inoculation had no effect(P>0.05) on gas production characteristics, dry matter, organic matter and neutral detergent fiber disappearance, pH, and concentration and composition of volatile fatty acids. Population of proteolytic bacteria and protozoa, but not cellulolytic bacteria, were increased(P<0.05) when RF was inoculated with termite bacteria with both WS and DL substrates. Inoculation of RF with termite bacteria increased protease activity, while activities of carboxymethyl-cellulase, microcrystalline-cellulase, α-amylase and filter paper degrading activity remained unchanged(P>0.05). Overall, the results of this study indicated that transferring lignocellulose-degrading bacteria, isolated from digestive tract of termite, to rumen liquid increased protozoa and proteolytic bacteria population and consequently increased protease activity and ammonia-N concentration in vitro, however, no effect on fermentation and fiber degradation parameters were detected. These results suggest that the termite bacteria might be rapidly lysed by the rumen microbes before beneficial effects on the rumen fermentation process could occur.
文摘Growth and differentiation factor-11 (GDF-11) is a secreted protein that is closely related to myostatin, a known inhibitor of skeletal muscle development. The role of GDF-11 in regulating skeletal muscle growth remains unclear and the pattern of expression during post-natal growth has not been reported. Therefore, we sought to determine the expression of GDF-11 during post-natal growth and its effect on myoblast proliferation and differentiation. We collected gastrocnemius muscles from male and female mice at 2, 3, 4, 6, 12, 20 and 32 weeks of age (n = 6 per sex and age). In addition, gastrocnemius muscles were col- lected from male wild-type and myostatin knockout mice at 4, 6, 12 and 20 weeks of age (n = 6 per age and genotype). RNA was extracted and reverse tran- scribed. Northern analysis identified an expected 4.4 kb mRNA transcript for GDF-11 in gastrocnemius muscles of mice. The concentration of GDF-11 mRNA, as determined by quantitative PCR, was increased in gastrocnemius muscles from 2 to 6 weeks—a period of rapid postnatal muscle growth—and remained higher in male than female mice from 4 to 20 weeks of age (P gastrocnemius muscles of myostatin knockout compared with wild-type mice (P < 0.05), which may suggest a compensatory mecha- nism for the lack of myostatin. In support, recombi- nant GDF-11 inhibited differentiation of C2C12 mur- ine myoblasts and those isolated from myostatin knockout and wild-type mice (P < 0.05). Inhibited dif-ferentiation of C2C12 myoblasts was associated with decreased mRNA expression of early and late mo- lecular markers of differentiation (MyoD, myogenin, IGF-II, desmin and MyHC, P < 0.05). Our results suggest that GDF-11 regulates growth of skeletal muscles by inhibiting myoblast differentiation in an autocrine/paracrine manner and, perhaps, also plays a role in regulating sexually dimorphic growth.
基金Foundation for Research, Science and Technology, C02X0403: Gene-specific Foods
文摘AIM: To investigate the role that single nucleotide polymorphisms (SNPs) in the promoter of the tumour necrosis factor-alpha (TNF-α) gene play in the risk of inflammatory bowel diseases (IBDs) in a New Zealand population, in the context of international studies. METHODS: DNA samples from 388 patients with Crohn's disease (CD), 405 ulcerative colitis (UC), 27 indeterminate colitis (IC) and 201 randomly selected controls, from Canterbury, New Zealand were screened for 3 common polymorphisms in the TNF-α receptor: -238 G→A, -308 G→A and -857C→T, using a TaqmanR assay. A meta-analysis was performed on the data obtained on these polymorphisms combined with that from other published studies. RESULTS: Individuals carrying the -308 G/A allele had a significantly (OR = 1.91, χ2 = 17.36, P < 0.0001) increased risk of pancolitis, and a 1.57-fold increased risk (OR = 1.57, χ2 = 4.34, P = 0.037) of requiring a bowel resection in UC. Carrying the -857 C/T variant decreased the risk of ileocolonic CD (OR = 0.56, χ2 =4.32, P = 0.037), and the need for a bowel resection (OR = 0.59, χ2 = 4.85, P = 0.028). The risk of UC was reduced in individuals who were smokers at diagnosis, (OR = 0.48, χ2 = 4.86, P = 0.028). CONCLUSION: TNF-α is a key cytokine known to play a role in inflammatory response, and the locus for the gene is found in the IBD3 region on chromosome 6p21, known to be associated with an increased risk for IBD. The -308 G/A SNP in the TNF-α promoter is functional, and may account in part for the increased UC risk associated with the IBD3 genomic region. The -857 C/T SNP may decrease IBD risk in certain groups. Pharmaco- or nutrigenomic approaches may be desir- able for individuals with such affected genotypes.
基金Project supported by the Knowledge Innovation Program of Chinese Academy of Sciences (No.KZCX2-413-3)National Natural Science Foundation of China (No.30390080)National Basic Research Program of China (No.2005CB121108)
文摘响应到稻田的脲申请的氨挥发损失,氮利用效率,和米饭收益在 Wangzhuang 镇上被调查, Changshu 城市,江苏省,中国。N 化肥处理,适用在三倍,是 0 (控制) , 100, 200, 300,或 350 kg N 哈 ? 1。在脲被用于地面水以后,一个连续气流包围方法被用来在稻田测量氨挥发。通过氨挥发的全部的 N 损失通常与 N 申请率,和申请评估的二更高的 N 增加了(300 和 350 kg N 哈 ? 1 ) 证明 N 的更高的比率通过氨挥发输了到应用 N。由在全部米饭期间,生长上演的氨挥发的全部的氨损失从 9.0% ~ 16.7% 应用 N 。增加申请率通常减少了在到在植物的 N 的种子的 N 的比率。为所有 N 处理,氮肥利用效率从 30.9% ~ 45.9%。有最高的 N 率的剩余 N 导致了米饭植物,氮肥利用的减少的率,和减少的米饭收益的住宿。从这个实验计算,最节俭的 N 化肥申请率是 227 kg 哈 ? 1 为在泰胡·莱克区域的水稻土的类型。然而,推荐适当 N 化肥申请率以便植物生长被提高,氨损失被减少能改进大米的 N 利用效率。
基金the National Natural Science Foundation of China through grant numbers 30270785 948 Project 0ffice, Ministry of Agriculture, China, through grant numbers 201068.
文摘A system to control the release of phosphate in water was successfully established, based on solubility product of [Ca^2+] and [PO4^3-] using tricalcium phosphate as P source in the hydroponic solution, and adding CaCl2 for supplementing extra Ca^2+. The system, similar to soil solutions, was a P nutrient buffer solution with very low bioavailable P. The buffer solution induced the roots of both monocotyledon and dicotyledon species to grow abundant root hairs, 3 mm in maximum length. The monocotyledons were corn (Zea mays L.) (var. Yellow Rose), wheat (Triticum aestivum L.) (var. Yanzhong 144), Triticale secale L. (vat. Jingsong 5), and ryegrass (Lolium rigidum L.) (var. Ruanni), and the dicotyledons were Arabidopsis thaliana L. (var. Columbia), white clover (Trifolium repens) (var. Kopu), Lotus (Lotus peduncucatus Cav. Luliginosus Schkuhr) (var. Grasslands Maku). For these species we proved that the root environment controls the induction of root hair formation. However, the hydroponic buffer solution failed to induce root hairs on the roots of onion (Allium cepa L.). Other investigators have concluded that corn does not form root hairs in hydroponics, but abundant long root hairs on corn were induced by this buffer system. The roots with abundant long root hairs are called "hedgehog roots" because they have hairs everywhere just like a hedgehog.
基金funded by the earmarked fund for China Agriculture Research System (CARS-34-07)the National Department of Public Benefit Research Foundation, China (201303057)
文摘The aphid quantity ratio(AQR) is defined as the number of aphids on each cultivar divided by the number of aphids on all cultivars. AQR is based on the correlation between aphid populations and their host plants and is an important tool that has been utilized in evaluating Medicago sativa(alfalfa) cultivar resistance to aphids. However, assessment of alfalfa resistance to aphids can be confused by the presence of aphid predators, causing the assessment of plant resistance to aphids to be based on incorrect aphid population data. To refine the AQR and account for the effect of predators on aphid population assessments, we introduced a parameter ‘α', corresponding to the predator quantity ratio, and used αAQR as the ratio to quantify aphid populations. Populations of both aphids(4 species) and their predators(12 species) occurring in 28 M. sativa cultivars were sampled over two years at a research station near Cangzhou, Hebei Province, China. Results showed that the most suitable evaluation period was from May to June, as the aphid population was stable during this period. Compared with the AQR method, the predator population numbers based on the αAQR had a significant inverse relationship with aphid population numbers and the 28 cultivars were clustered into three classes: the resistant class, tolerant class, and susceptible class. In addition, 17 cultivars were reassigned when evaluated using αAQR. All numerical values calculated by αAQR were displayed as a Gaussian distribution, which showed that the 28 cultivars could be clustered into nine groups using a median value(±SE) of 1±0.1. Hence, ongoing alfalfa breeding trials will be assessed using the αAQR to establish a robust system that includes agronomic performance parameters in order to generalize the new method for further studies.
基金the Beef Producers of Ontario,Ontario Ministry of Agriculture and Rural Affairs,Beef Cattle Research Council and Agri-Food Canada for financial support
文摘Background: Despite its variety of potential applications, the wide implementation of infrared technology in cattle production faces technical, environmental and biological challenges similar to other indicators of metabolic state. Nine trials, divided into three classes (technological, environmental and biological factors) were conducted to illustrate the influence of these factors on body surface temperature assessed through infrared imaging. Results: Evaluation of technological factors indicated the following: measurements of body temperatures were strongly repeatable when taken within ]0 s; appropriateness of differing infrared camera technologies was influenced by distance to the target; and results were consistent when analysis of thermographs was compared between judges. Evaluation of environmental factors illustrated that wind and debris caused decreases in body surface temperatures without affecting metabolic rate; additionally, body surface temperature increased due to sunlight but returned to baseline values within minutes of shade exposure. Examination/investigation/exploration of animal factors demonstrated that exercise caused an increase in body surface temperature and metabolic rate. Administration of sedative and anti-sedative caused changes on body surface temperature and metabolic rate, and during late pregnancy a foetal thermal imprint was visible through abdominal infrared imaging. Conclusion: The above factors should be considered in order to standardize operational procedures for taking thermographs, thereby optimizing the use of such technology in cattle operations.
文摘Protein-based animal fibres of commercial importance are frequently exposed to elevated temperatures during processing treatments. Hydrothermal processes cause protein deterioration, impacting negatively on the value or condition of these materials. This study was designed to investigate hydrothermal damage in wool proteins at the molecular level. The effect of hydrothermal damage on Type I and II intermediate filament proteins (keratins) extracted from wool was characterised using advanced quantitative techniques based on isobaric iTRAQ labelling and mass spectrometry. Many native peptides were observed to be degraded and modified. Amongst these, twenty keratin peptides were observed to consistently degrade during hydrothermal exposure. These peptides acted as molecular markers of damage – specific indicators of the extent of heat-induced protein damage. This technology will be of value in assessing the severity of damage imparted after high temperature exposure of protein-based animal fibres such as wool and cashmere during processes such as dyeing and carbonising, or even after high temperature human hair treatments. The identification of molecular damage markers identified within wool and other materials provides a new route to sensitive and specific evaluation of the effects of protein deterioration. It is anticipated that the utilisation of such markers will facilitate the development of targeted approaches to minimising processing damage to high-value fibres and protein-based biomaterials.
基金supported by New Zealand dairy farmers through DairyNZ Inc.(RD1403)the Ministry of Business,Innovation,and Employment(DRCX1201).
文摘Background:In seasonal,pasture-based,dairy production systems,cows must recover from calving and become pregnant within two to 3 months.To achieve this,the uterus must involute and ovulation must occur and continue at regular intervals.As these processes are affected by the cows’nutritional or metabolic status post-calving,the objective of this study was to evaluate the effect of cow feeding strategies on uterine health,the length of postpartum anestrous interval,and reproductive outcomes.The treatments consisted of two feeding strategies during late-lactation and early dry period(far-off period;starting 4-month pre-calving)and three close-up dry period feeding regimes(1-month pre-calving)in a 2×3 factorial arrangement.We randomly assigned 150 cows to one of two far-off treatments.During late lactation,the herds(n=75 cows per herd)were either control-fed(Controlfed)or over-fed(Overfed)to achieve a low or high body condition score(4-month pre-calving;BCS;~4.25 and^4.75;10-point scale)at cessation of lactation.Within each of these treatments,three feeding levels were applied during the close-up period(1-month pre-calving):~65%(Feed65),~90%(Feed90),or^120%(Feed120)of metabolizable energy(ME)intakes relative to pre-calving requirements.Results:Uterine health improved(i.e.polymorphonucleated(PMN)cells declined)with increased feeding during the close-up period for cows in the Overfed group.The reverse was evident for the Controlfed group with the greatest PMN at the highest intakes during the close-up period.The postpartum anoestrous interval(PPAI)was shorter in cows from the Overfed group when moderately fed(Feed90)during the close-up period;in comparison,the PPAI was shorter in the Controlfed group,when those cows were overfed in the close-up period(Feed120).The cows in the Overfed treatment had greater conception and pregnancy rates if cows had moderate dry matter intakes(Feed90)during the close-up period;these reproductive variables were less under excessive feed intakes(Feed120);yet,close-up dry matter intake had little effect on conception and pregnancy rates for the Controlfed group.Conclusions:The far-off feeding strategies increased early reproductive outcomes at 3 weeks of mating.Additionally,the interaction between far-off and close-up feeding strategies resulted in high six-week pregnancy rate with a slight restriction during the close-up period but only in the far-off Overfed group.Thus,our hypothesis is supported under these conditions.
基金supported by the National Transgenic Project(2009ZX08007-009B, 2011ZX08007-003)Guangxi natural science funding(2012GXNSFCB053002)+1 种基金funding of State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources(KSL-CUSAb-2012-02)supported by AgResearch core funding
文摘Background: Cytoplasmic injection of exogenous DNA into zygotes is a promising technique to generate transgenic livestock. However, it is still relatively inefficient and has not yet been demonstrated to work in buffalo. We sought to improve two key technical parameters of the procedure, namely i) how much linear DNA to inject and ii) when to inject it. For this, we introduced a constitutively expressed enhanced green fluorescent protein (EGFP) plasmid into buffalo zygotes. Results: First, we found that the proportion of EGFP-expressing blastocysts derived from zygotes injected with 20 or 50 ng/pL DNA was significantly higher than from those injected with 5 pg/mL. However, 50 ng/pL exogenous DNA compromised blastocyst development compared to non-injected IVF controls. Therefore the highest net yield of EGFP-positive blastocysts was achieved at 20 ng/pL DNA. Second, zygotes injected early (7-8 h post-insemination [hpi]) developed better than those injected at mid (12-13 hpi) or late (18-19 hpi) time points. Blastocysts derived from early injections were also more frequently EGFP-positive. As a consequence, the net yield of EGFP-expressing blastocysts was more than doubled using early vs late injections (16.4 % vs 7.7 %). With respect to blastocyst quality, we found no significant difference in cell numbers of EGFP-positive blastocysts vs non-injected blastocysts. Following embryo transfer of six EGFP-positive blastocysts into four recipient animals, two viable buffalo calves were born. Biopsied ear tissues from both buffalo calves were analyzed for transgene presence and expression by Southern blot, PCR and confocal laser scanning microscopy, respectively. This confirmed that both calves were transgenic. Conclusions: Our cytoplasmic injection protocol improved generation of transgenic embryos and resulted in the first transgenic buffalo calves produced by this method.
文摘Fungal Epichloëendophytes form symbiotic associations with many temperate grasses,such as Lolium and Festuca,giving their host grasses an ecological advantage.The importance of specific Epichloëendophytes in providing varying levels of protection against invertebrate pests has been well documented.Similarly,but with fewer studies,the benefits of Epichloëto host grasses in drought events has been shown.Endophyte-infected grasses show an improved persistence against herbivore insect attack as well as resilience under drought.However,there are relatively few studies that investigate the interaction between drought and insect pressure,and yet it is these combined pressures that can prove detrimental for a ryegrass or fescue crop.This review examines the current state of knowledge on the effects of Epichloëon the interactions of insects and drought in temperate grasses.