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Over the past few decades,genetic selection and refined nutritional management have extensively been used to increase the growth rate and lean meat production of livestock.However,the rapid growth rates of modern breeds are often accompanied by a reduction in intramuscular fat deposition and increased occurrences of muscle abnormalities,impairing meat quality and processing functionality.Early stages of animal development set the longterm growth trajectory of offspring.However,due to the seasona...  相似文献   

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Background: Improving feed efficiency(FE) is one of the main objectives in broiler breeding. It is difficult to directly measure FE traits, and breeders hence have been trying to identify biomarkers for the indirect selection and improvement of FE traits. Metabolome is the "bridge" between genome and phenome. The metabolites may potentially account for more of the phenotypic variation and can suitably serve as biomarkers for selecting FE traits. This study aimed to identify plasma metabolite mar...  相似文献   

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Background: Artificial insemination is a preferred breeding method for beef heifers as it advances the genetic background, produces a predictive and profitable calving season, and extends the heifer's reproductive life span.As reproductive efficiency in heifers is key for the success of beef cattle production systems, following artificial insemination, heifers are exposed to a bull for the remainder of the breeding season. Altogether, up to 95% of heifers might become pregnant in their first breeding season. Heifers that do not become pregnant at the end of the breeding season represent an irreparable economical loss. Additionally, heifers conceiving late in the breeding season to natural service, although acceptable, poses serious losses to producers. To minimize losses due to reproductive failure, different phenotypic parameters can be assessed and utilized as selection tools. Here, we tested the hypothesis that in a group of pre-selected heifers, records of weaning weight, age at weaning, age at artificial insemination, and age of dam differ among heifers of varied reproductive outcomes during the first breeding season.Results: None of the parameters tested presented predictive ability to discriminate the heifers based on the response variable(‘pregnant to artificial insemination', ‘pregnant to natural service', ‘not pregnant'). Heifers categorized with body condition score = 6 and reproductive tract score ≥ 4 had the greatest proportion of pregnancy to artificial insemination(49% and 44%, respectively). Furthermore, it was notable that heifers presenting body condition score = 6 and reproductive tract score = 5 presented the greatest pregnancy rate at end of the breeding season(89%). Heifers younger than 368 d at the start of the breeding season did not become pregnant to artificial insemination. Those young heifers had 12.5% chance to become pregnant in their first breeding season,compared to 87.5% if the heifers were older than 368 days.Conclusion: Our results suggest that beef heifers with body condition score = 6 and reproductive tract score ≥ 4 are more likely to become pregnant to artificial insemination. Careful assessment should be undertaken when developing replacement heifers that will not reach 12 months of age by the beginning of the breeding season.  相似文献   

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Background Carcass traits are crucial for broiler ducks,but carcass traits can only be measured postmortem.Genomic selection(GS) is an effective approach in animal breeding to improve selection and reduce costs. However,the performance of genomic prediction in duck carcass traits remains largely unknown.Results In this study,we estimated the genetic parameters,performed GS using different models and marker densities,and compared the estimation performance between GS and conventional BLUP on 35 c...  相似文献   

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Background:Intrauterine growth retardation(IUGR) is associated with severely impaired nutrient metabolism and intestinal development of pigs.Our previous study found that IUGR altered intestinal microbiota and metabolites in the colon.However,the consequences of IUGR on bile acid metabolism in pigs remained unclear.The present study aimed to investigate the bile acid metabolism in the liver and the profile of bile acid derivatives in the colon of growing pigs with IUGR using bile acid targeted m...  相似文献   

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This study was conducted to investigate the effects of fermented mixed feed(FMF) on growth performance, carcass traits, meat quality, muscle amino acid and fatty acid composition and mRNA expression levels of genes related to lipid metabolism in finishing pigs. In the present study, 144 finishing pigs(Duroc × Berkshire × Jiaxing Black) were randomly allocated to 3 dietary treatments with 4 replicate pens per group and 12 pigs per pen. The dietary treatments included a basal diet(CON), a basal di...  相似文献   

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Four crossbred （Duroc x Landrace x Yorkshire） boars, weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources （maize ,brown rice, sticky rice, and resistant starch） on the absorption of energy sources through the portal vein. Portal blood flow averaged 30.68, 28.40, 29.99, and 30. 12 mL/min per kg BW for pigs fed the maize, brown rice, sticky rice, and resistant starch diets, respectively, and did not dif- fer （P 〉 0.05） between treatments. The absorptions of glucose, plasma ammonia, and total amino acids were significantly lower （P 〈 0.05 ） in pigs fed the resistant starch diet than pigs fed the other starch sources. In contrast, significantly （ P 〈 0.05 ） higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize, brown rice, or sticky rice. In addition, significantly （P 〈 0.05） more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets. The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly （P 〈 0.05） lower in pigs fed the resistant starch diet than pigs fed the other three starch sources. In contrast, the amount of energy absorbed in the form of volatile fatty acids was significantly （P 〈 0.05 ） higher in pigs fed resistance starch than pigs fed the other three starch sources. The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%, respectively, which were significantly （P 〈 0.05 ） higher than the values in pigs fed resistant starch （41.5% and 46.6% respectively）. The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources. Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies, while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies.  相似文献   

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Four crossbred(Duroc×Landrace×Yorkshire)boars,weighing an average of 22.40 ± 1.08 kg and fitted with permanent catheters in their portal and mesenteric veins as well as their carotid artery,were utilized in a 4 × 4 latin square design experiment in order to investigate the effects of different starch sources(maize,brown rice,sticky rice,and resistant starch)on the absorption of energy sources through the portal vein.Portal blood flow averaged 30.68,28.40,29.99,and 30.12 mL/min per kg BW for pigs fed the maize,brown rice,sticky rice,and resistant starch diets,respectively,and did not differ(P0.05)between treatments.The absorptions of glucose,plasma ammonia,and total amino acids were significantly lower(P0.05)in pigs fed the resistant starch diet than pigs fed the other starch sources.In contrast,significantly(P0.05)higher amounts of propionate and total volatile fatty acids were absorbed from the portal vein of pigs fed resistant starch than pigs fed diets based on maize,brown rice,or sticky rice.In addition,significantly(P0.05)more lactic acid was absorbed from the portal vein by pigs fed the sticky rice diet than pigs fed the other three diets.The energy absorbed from the portal vein in the form of glucose and amino-N as well as the total energy absorbed was significantly(P0.05)lower in pigs fed the resistant starch diet than pigs fed the other three starch sources.In contrast,the amount of energy absorbed in the form of volatile fatty acids was significantly(P0.05)higher in pigs fed resistance starch than pigs fed the other three starch sources.The total energy absorbed through the portal vein as a percentage of the gross energy and digestible energy consumed in pigs fed maize were 50.8% and 54.6%,respectively,which were significantly(P0.05)higher than the values in pigs fed resistant starch(41.5% and 46.6% respectively).The results indicate that energy is absorbed in different forms and with different utilization efficiencies in the digestive tract of pigs as a result of feeding different starch sources.Starch sources supplying most of their energy in the form of glucose had higher energy utilization efficiencies,while starch sources supplying most of their energy in the form of volatile fatty acids or lactic acid had lower energy utilization efficiencies.  相似文献   

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Meat and milk production needs to increase ～ 70–80% relative to its current levels for satisfying the human needs in 2050.However,it is impossible to achieve such genetic gain by conventional animal breeding systems.Based on recent advances with regard to in vitro induction of germ cell from pluripotent stem cells,herein we propose a novel embryo-stem cell breeding system.Distinct from the conventional breeding system in farm animals that involves selecting and mating individuals,the novel breeding system completes breeding cycles from parental to offspring embryos directly by selecting and mating embryos in a dish.In comparison to the conventional dairy breeding scheme,this system can rapidly achieve 30–40 times more genetic gain by significantly shortening generation interval and enhancing selection intensity.However,several major obstacles must be overcome before we can fully use this system in livestock breeding,which include derivation and mantaince of pluripotent stem cells in domestic animals,as well as in vitro induction of primordial germ cells,and subsequent haploid gametes.Thus,we also discuss the potential efforts needed in solving the obstacles for application this novel system,and elaborate on their groundbreaking potential in livestock breeding.This novel system would provide a revolutionary animal breeding system by offering an unprecedented opportunity for meeting the fast-growing meat and milk demand of humans.  相似文献   

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Background Cold regions have long autumn and winter seasons and low ambient temperatures. When pigs are unable to adjust to the cold, oxidative damage and inflammation may develop. However, the differences between cold and non-cold adaptation regarding glucose and lipid metabolism, gut microbiota and colonic mucosal immunological features in pigs are unknown. This study revealed the glucose and lipid metabolic responses and the dual role of gut microbiota in pigs during cold and non-cold adaptat...  相似文献   

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Eighteen (Duroc × Landrace × Yorkshire) castrated boars,55 days of age and weighing approximately 19 kg,were used to investigate the effects of montmorillonite nanocomposite on tissue levels of lead as well as changes in blood biochemical parameters in pigs fed lead contaminated diets.The barrows were randomly assigned to one of three treatments (n=6) including a control which were fed a basal diet based on corn and soybean meal.The remaining two groups were fed the basal diet supplemented with 10 mg/kg lead either with or without 0.5% montmorillonite nanocomposite for 50 days.Pigs treated with lead had significantly increased levels of lead in their tissues.Lead accumulated in all tissues of the body with the highest accumulation found in the hair.When montmorillonite nanocomposite was given along with lead,tissue concentrations of lead did not differ from the control.Fecal excretion of lead increased significantly in lead-exposed pigs treated with montmorillonite nanocomposite.A progressive and appreciable accumulation of lead was seen in blood with a concomitant increase in zinc protoporphyrin levels during the course of treatment.However,zinc protoporphyrin levels did not differ from the control when montmorillonite nanocomposite was administered along with lead.The activity of δ-amino levulinic acid dehydratase in blood was significantly increased in lead treated pigs compared with the control.However,in pigs treated with lead and montmorillonite nanocomposite in combination,the activity of δ-amino levulinic acid dehydratase was similar to control pigs.Our results indicate that montmorillonite nanocomposite treatment of pigs exposed to lead resulted in reduced lead concentrations in body tissues.It appears that montmorillonite nanocomposite functions by increasing fecal excretion of lead.  相似文献   

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This study was conducted to evaluate the supplementation of glutamic acid(Glu)to reduced protein diets on the performance of weanling pigs.One hundred and eighty crossbred weanling pigs([YorkshireLandrace]Duroc,21 d old)having similar body weight(BW)of 6.45 kg were randomly allotted to 1 of 6 dietary treatments(5 pigs per pen[2 barrows and 3 gilts];6 pens per treatment)based on BW and sex during a 6-week trial.Dietary treatments consisted of positive control(PC)diet formulated to have 226.9,205.6,and 188.8 g crude protein(CP)during phases 1,2,and 3,respectively,and negative control(NC)diets with 20 g CP reduction from PC diets and addition of Glu with increasing levels,resulting in the calculated Lys-to-Glu ratios of 1:2.25,1:2.30.1:2.35,1:2.40,and 1:2.45,designated as NC,NC1,NC2,NC3,and NC4,respectively.The BW of pigs receiving PC diet was higher(P<0.05)than those receiving NC diet at d 7,21 and 42.A higher(P<0.05)average daily gain(ADG)from d 1 to 7,8 to 21,22 to 42 and during the overall experiment period was observed in pigs fed PC than NC diet.Pigs fed NC diets including the graded level of Glu linearly increased(P<0.05)BW at d 42,ADG and gain-to-feed ratio(G:F)during the overall experimental period.In addition,trends in linear increase in BW(P=0.056)at d 7 and ADG from d 1 to 7 and d 22 to 42(linear effect,P=0.081,P=0.058 respectively)were observed.A tendency in the linear increment of NH3(P=0.082)at d 21 and linear reduction in methyl mercaptans(P=0.054)emission at d 42 was observed in pigs fed NC diets supplemented with graded level of Glu.In conclusion,supplementing the reduced protein diet with Glu enhanced the growth performance in weanling pigs suggesting that supplementation of Glu can compensate the reduction of 2%CP in the basal diets.  相似文献   

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A total of 2,121 growing-finishing pigs (Duroc × Landrace × Large White) were utilized in six experiments conducted to determine the effects of different ratios of standardized ileal digestible lysine (SID-Lys) to metabolizable energy (ME) on the performance and carcass characteristics of growing-finishing pigs. Exps. 1 (30 to 50 kg), 2 (52 to 70 kg) and 3 (81 to 104 kg) were conducted to find an optimum ME level and then this level was used in Exps. 4 (29 to 47 kg), 5 (54 to 76 kg) and 6 (84 to 109 kg) to test the response of pigs to different ratios of SID-Lys:ME. In Exps.1 to 3, four treatments were used consisting of diets with a formulated ME content of 3.1, 3.2, 3.3 or 3.4 in Exps. 1 and 2 while Exp. 3 used 3.05, 3.15, 3.25 or 3.35 Mcal/kg. A constant SID-Lys:ME ratio of 2.6, 2.3 or 2.0 g/Mcal was used in Exps. 1, 2 and 3, respectively. Weight gain was significantly increased with increasing energy level in Exp.1 while weight gain was unaltered in Exps. 2 and 3. For all three experiments, feed intake was decreased (P < 0.05) and feed efficiency was improved (P < 0.05) with increasing energy level. Tenth rib back fat thickness linearly increased (P < 0.05) with increasing energy level. In Exps. 4 to 6, five treatments were used consisting of diets with a SID-Lys:ME ratio of 2.4, 2.6, 2.8, 3.0 or 3.2 in Exp. 1, 2.1, 2.3, 2.5, 2.7, 2.9 or 3.2 in Exp. 2 and 1.8, 2.0, 2.2, 2.4, or 2.6 in Exp. 3. A constant ME level 3.2, 3.2 and 3.05 Mcal/kg was used in Exps. 1, 2 and 3, respectively (selected based on the results of weight gain). For all three experiments, weight gain increased (P < 0.05) and feed efficiency improved linearly (P < 0.05) as the SID-Lys:ME ratio increased. Tenth rib back fat thickness linearly decreased (P < 0.05) as the SID-Lys:ME ratio increased. Based on a straight broken-line model, the estimated SID-Lys:ME ratio to maximize weight gain was 3.0, 2.43 and 2.2 for 29 to 47, 54 to76 and 84 to 109 kg of pigs, respectively.  相似文献   

16.
Background:There is a lack of data for the standardized ileal digestibility(SID) of fat and fatty acids in national feed databases.In addition,it is important to specify the procedures used for fat analyses.Therefore,an experiment was conducted to 1) determine the apparent ileal digestibility(AID) and SID of fat and fatty acids in ten different oil sources for growing pigs and to develop prediction equations for SID of fat based on fatty acid composition;and 2) compare the effect of the fat extr...  相似文献   

17.
ABSTRACT： Eighteen （Duroc x Landrace x Yorkshire） castrated boars, 55 days of age and weig- hing approximately 19 kg, were used to investigate the effects of montmorillonite nanocomposite on tissue levels of lead as well as changes in blood biochemical parameters in pigs fed lead contaminated diets. The barrows were randomly assigned to one of three treat- ments （n = 6） including a control which were fed a basal diet based on corn and soybean meal. The re- maining two groups were fed the basal diet supple- mented with 10 mg/kg lead either with or without 0.5% montmorillonite nanocomposite for 50 days. Pigs treated with lead had significantly increased lev- els of lead in their tissues. Lead accumulated in all tis- sues of the body with the highest accumulation found in the hair. When montmorillonite nanocomposite was given along with lead, tissue concentrations of lead did not differ from the control. Fecal excretion of leadincreased significantly in lead-exposed pigs treated with montmorillonite nanocomposite. A progressive and appreciable accumulation of lead was seen in blood with a concomitant increase in zinc protopor- phyrin levels during the course of treatment. Howev- er, zinc protoporphyrin levels did not differ from the control when montmorillonite nanocomposite was ad- ministered along with lead. The activity of ~-amino le- vulinic acid dehydratase in blood was significantly in- creased in lead treated pigs compared with the con- trol. However, in pigs treated with lead and montmo- riltonite nanocomposite in combination, the activity of δ-amino levulinic acid dehydratase was similar to con- trol pigs. Our results indicate that montmorillonite nanocomposite treatment of pigs exposed to lead re- suited in reduced lead concentrations in body tissues. It appears that montmorillonite nanocomposite func- tions by increasing fecal excretion of lead.  相似文献   

18.
Background: β-defensins have attracted considerable research interest because of their roles in protecting hosts from various pathogens. This study was conducted to investigate the expression profiles of the porcine β-defensin114(PBD114) in different breeds and in response to infections. Moreover, the function of PBD114 protein was partially investigated.Methods: Six Tibetan pigs(TP) and six DLY(Duroc×Landrace×Yorkshire) pigs were slaughtered to explore the expression profiles of PBD114 in different breeds and tissues. For infection models, sixteen DLY pigs were divided into two groups and challenged either with sterile saline or E. coli K88. The recombinant protein PBD114(r PBD114)was obtained by using a heterologous expression system in E. coli.Results: PBD114 gene was highly expressed in tissues such as the intestine, liver, spleen, and thymus. Interestingly,the expression level of PBD114 gene was higher in the TP pigs than in the DLY pigs(P 0.05), and was significantly elevated upon E. coli K88 challenge(P 0.05). The nucleotide sequences of PBD114 from Tibetan and DLY pigs was identical, and both showed a 210-bp open reading frame encoding a 69-amino acid mature peptide. To explaore the function of PBD114 protein, PBD114 gene was successfully expressed in E. coli Origami B(DE3) and the molecular weight of the r PBD114 was estimated by SDS-PAGE to be 25 k Da. The r PBD114 was purified and mass spectrometry verified the protein as PBD114. Importantly, r PBD114 showed antimicrobial activities against E. coli DH5α and E. coli K88,and the minimal inhibitory concentrations(MICs) were 64 and 128 μg/m L, respectively. Hemolytic and cytotoxicity assays showed that r PBD114 did not affect cell viability under physiological concentrations.Conclusions: PBD114 is an infection response gene that is differentially-expressed between different porcine breeds and tissues. The antimicrobial activity of PBD114 protein, against pathogens such as the E. coli K88, suggested that it may serve as a candidate for the substitution of conventionally used antibiotics.  相似文献   

19.
Background: The interaction of the gut microbiota with key metabolic and physiological processes may be associated with poor growth outcomes in animals born with intrauterine growth restriction(IUGR).Results: Growth performance, plasma hormone concentrations, and intestinal microbiota composition were analyzed in IUGR pigs and in normal birth weight(NBW) pigs when the NBW pigs reached 25, 50, and 100 kg of body weight(BW). Compared to NBW pigs, IUGR pigs had lower initial, weaned, and final BW, and lower average daily gain and average daily feed intake in all the considered time points. In the 25 kg BW group, IUGR pigs had higher concentrations of plasma ghrelin and pancreatic polypeptide(PP), but lower insulin concentration than NBW pigs, while the situation was reversed in the 50 kg BW group. As compared to NBW pigs, IUGR pigs had higher microbial alpha diversity in the jejunum and ileum;in the 50 and 100 kg BW groups, IUGR pigs had higher Firmicutes abundance but lower Proteobacteria abundance in the jejunum, and lower Lactobacillus abundance in the jejunum and ileum;in the 25 kg BW group, IUGR pigs showed higher unclassified Ruminococcaceae abundance in the ileum;and in 25 and 50 kg BW groups, IUGR pigs showed lower Ochrobactrum abundance in the jejunum.Spearman's correlation revealed that Lactobacillus was negatively correlated with growth performance, while unclassified Ruminococcaceae was positively correlated. Predictive metagenomic analysis detected significantly different expression of genes in the intestinal microbiota between IUGR and NBW pigs, suggesting different metabolic capabilities between the two groups.Conclusions: Growing-finishing IUGR pigs showed lower growth performance, higher microbial alpha diversity, and differences in plasma hormone concentrations compared to NBW pigs. Alterations in the abundance of Firmicutes,Proteobacteria, Ruminococcaceae, Lactobacillus, and Ochrobactrum in the small intestine may be associated with IUGR, and may therefore serve as a future target for gut microbiota intervention in growing-finishing IUGR pigs.  相似文献   

20.
Background: There is large variation in amino acids requirements among pigs, hence feeding pigs individually with daily tailored diets or in groups with a single feed may require different levels of nutrients. Thus, the response to different threonine levels(70%, 85%, 100%, 115%, and 130% of the ideal threonine:lysine protein ratio of 0.65) was studied in growing pigs raised in a conventional group phase-feeding(GPF) system or fed individually using individual precision-feeding(IPF) techniques. In a 21-day trial, 110 barrows(25 ± 0.80 kg body weight) were housed in the same room and fed using electronic feeders. Five pigs per treatment were slaughtered at the end of the trial.Results: Threonine intake increased linearly for the IPF and GPF pigs(P 0.05). Lysine intake was similar across the treatments. Average daily gain, gain:feed ratio, and protein deposition were affected linearly by threonine level(P 0.05)in both feeding systems. Protein deposition in the GPF pigs was maximized at 150 g/d and a 0.65 threonine:lysine ratio, whereas protein deposition increased linearly in the IPF pigs. Plasma Met and serine levels were 11 and 7% higher, respectively, in the IPF pigs than in the GPF pigs(P 0.05). Dietary threonine increased(P 0.05)threonine concentration in the longissimus dorsi in a quadratic manner in the IPF pigs, whereas there was no effect in the GPF pigs. Longissimus dorsi collagen decreased as dietary threonine increased in the IPF and GPF pigs(P 0.10). Carcass muscle crude protein was 2% higher in the GPF pigs than in the IPF pigs(P 0.05).Conclusions: Individual pigs are able to modulate growth and the composition of growth according to threonine intake. The average amino acid ratio value that is currently used for GPF cannot be used for IPF.  相似文献   

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