Animal Bioscience最新文献

Objective: Body conformation traits directly impact carcass performance in the meat goat industry. This study explored the population genetics of two Chinese goat breeds and identified the genomic variants associated with their body conformation traits.

Methods: The Guizhou black goat (GBG, n = 104) and Hezhang black goat (HBG, n = 100) underwent genotyping through whole-genome sequencing and phenotyping by measuring their body height (BH), body length (BL), chest depth (CD), chest width (CW), chest girth (CG), rump width (RW), rump height (RH), and cannon circumference (CC).

Results: The relatedness analysis showed that these goats exhibited low genetic kinship-related, with the GBG and HBG being relatively independent, albeit with some genetic introgression present. The lambda values showed that the reliability of the genome-wide association studies (GWAS) model, identifying a total of 33, 1, 6, 2, 5, 10, 21, and 13 single nucleotide polymorphisms (SNPs) as significantly correlated (p<8.33e-8) with BH, BL, CD, CW, CG, RW, RH, and CC, respectively. The GWAS for BH and RH identified the greatest number of significant SNPs, with a substantial overlap among them, mainly located in four regions: chr13_63286230-69784740 (10 SNPs), chr14_60354209-60376549 (six SNPs), and chr15_65605417-73873841 (five SNPs), and chr23_42819635-43332716 (nine SNPs). Individuals with a greater number of these SNPs displayed elevated BH and RH values. Following the annotation of all significant SNPs, 102 genes within a ±100 Kb region were identified. The most significantly enriched KEGG pathway was "Olfactory transduction", while the most significantly enriched GO terms included "cellular process" and "molecular transducer activity".

Conclusion: This study investigated the population genetics of two prominent Chinese goat breeds and identified several SNPs that are significantly associated with body conformation traits. These findings offer biological insights into enhancing growth performance and hold significant potential for practical application in the genomic selection of meat goats.

Objective: Imbalanced feeding of protein and energy in ruminants coupled with increasing concerns over low production efficiencies and high livestock emissions intensifies the feeding challenges, especially in buffaloes. This study was planned to evaluate the independent or interactive effects of dietary starch and crude protein (CP) on lactation performance, blood metabolites, and methane production of dairy buffaloes.

Methods: Sixteen lactating multiparous Nili Ravi buffaloes received the following dietary treatments of low (LS) or high starch (HS) content combined with low (LP) or high protein (HP) content in a 4×4 Latin square design: 1) LSLP, 2) LSHP, 3) HSLP, and 4) HSHP. Dietary starch contents were 19.5% and 28.7% in LS and HS diets, whereas CP contents were 8.8% and 10.6% in the LP and the HP diets, respectively.

Results: Although milk yield was not affected by dietary treatments, the HP diet increased milk protein and lactose contents compared with the LP diet in the HS group; however, no such increase was observed in LS group, resulting in a starch×CP interaction. Efficiencies of metabolizable protein and milk nitrogen decreased with the HP diet compared with the LP diet. Metabolic efficiency of metabolizable protein was higher in buffaloes fed the LS diet compared with HS diet. Rumen pH decreased with the HS diet compared with the LS diet in the HP group; however no such change was observed in the LP group. Methane production was increased with the LS diet compared with the HS diet. Contrarily, methane production was decreased in buffaloes fed HP diet compared with those fed the LP diet.

Conclusion: These findings indicated that dietary starch interacted with CP level for milk protein, milk lactose, rumen pH, and methane production of lactating buffaloes. Overall, HS combined with HP content can effectively improve milk protein and lactose contents while reducing the methane emission of lactating buffaloes.

Objective: This experiment evaluated the use of insect protein and phytonutrient-based tropical plant supplementation on rumen fermentation characteristics and microbial protein synthesis in Thai native beef cattle. Enhancing protein utilization and promoting rumen fermentation could be achieved by combining high-protein crickets and phytonutrients from mangosteen peel and lemongrass powder to a pellet (CMLP).

Methods: Four native male Thai beef cattle were randomly assigned treatments using a 4×4 Latin square design to receive four dietary treatments. The treatments were as follows: control (no supplementation), CMLP supplement at 50 g/h/d, CMLP supplement at 100 g/h/d and CMLP supplement at 150 g/h/d, respectively.

Results: Results revealed that the supplementation of CMLP in beef cattle did not influence rice straw intake, concentrate intake and total feed intake, which also enhanced the digestibility of crude protein, acid detergent fiber and neutral detergent fiber (p<0.05). Additionally, volatile fatty acid production of propionate and bacterial population were increased (p<0.05), and protozoal populations and production of methane decreased (p<0.05) with a higher level of CMLP supplementation. Furthermore, efficiency of microbial nitrogen synthesis significantly increased by increasing the level of CMLP supplementation, particularly at 150 g.

Conclusion: Our results suggested that CMLP supplementation, particularly at 150 g/h/d, enhanced nutrient digestibility, increased the propionic acid proportion, and promoted microbial protein synthesis while reducing protozoal populations and methane production. CMLP showed promise as an effective dietary protein supplement that improved rumen fermentation and performance of Thai native beef cattle.

Objective: Maximizing growth throughout the growth period is a practical goal in the beef industry. We developed a novel selection index, called the maximum growth index, that maximizes the growth throughout the growth process and simultaneously achieves the desired weight gain at designated time points by assigning arbitrary values to selection intensity.

Methods: We used a technique called Lagrange multipliers to maximize overall growth throughout the entire growth process and to restrict weight gains to desired amounts at specific times. We developed a selection index by applying random regression (RR) to the growth curve and using the genomically enhanced breeding values of the RR coefficients as selection index traits.

Results: Examples of the developed index was applied based on assumed data in Japanese Black steers. Selection to maximize growth during the growth period and to moderate birth weight yielded an upwardly convex curve for weight gain during the growth process, and the peak daily gain was greater and earlier than achieved without this selection. Under a selection intensity of 0.5, the index that constrained birth weight to decrease by 2.5 kg achieved the pre-selection final weight 8 weeks earlier than occurred without this selection.

Conclusion: We developed a beef cattle selection index that maximized total weight gain during growth yet constrained birth weight and other traits. The maximum growth index that we developed enables reductions in birth weight concurrent with increases in final weight, thus benefiting the beef industry by increasing final weight and preventing dystocia.

Objective: Tibial dyschondroplasia (TD) is a metabolic disorder of cartilage that impairs the development of the tibial growth plate in rapidly growing poultry. This study aimed to identify key genes and clarify the molecular mechanisms involved in TD in broiler chickens. The study evaluated the potential effect of vitamin D3 (VD3) in alleviating TD symptoms, focusing particularly on the role of Bone morphogenetic protein 8A (BMP8A) and its interaction with transforming growth factor-β1 (TGF-β1).

Methods: Ninety-four broiler chicks were allocated into three groups: healthy control, thiram-induced TD, and thiram-induced with VD3 supplementation. RNA sequencing was performed to identify differentially expressed genes (DEGs) among the groups. Target genes underwent additional validated using molecular biology techniques, such as gene expression analysis and in vitro functional assays on chondrocytes.

Results: VD3 effectively mitigated chondrocyte damage induced by thiram. RNA-seq revealed 625 DEGs enriched in pathways such as the TGF-β signaling pathway. Four co-DEGs (BMP8A, COL10A1, SDC3, and SCIN) were closely associated with collagen metabolism and reorganization. Functional assays, such as CCK8, EdU and IHC showed that BMP8A reduced collagen accumulation induced by elevated TGF-β1 levels, promoted the release of collagen types I, II, and X, and facilitated chondrocyte proliferation and differentiation while reducing apoptosis.

Conclusion: BMP8A plays a protective role in TD by the regulation of collagen balance and the maintenance of chondrocyte function, especially in the presence of high TGF-β1 levels. VD3 supplementation effectively reduces TD-related damage. The interaction between BMP8A and TGF-β1 may provide a novel therapeutic target for the prevention and treatment of TD in poultry.

Objective: Intestinal inflammatory diseases significantly affect animal health, primarily by disrupting intestinal barrier function. Indole-3-carboxaldehyde (IAld), a key metabolite of tryptophan derived from gut microbiota, exhibits protective properties against intestinal inflammatory diseases. The regulatory mechanism by which IAld modulates intestinal barrier function requires further investigation.

Methods: An intestinal epithelial cell injury model was established by tumor necrosis factor-alpha (TNF-α) stimulation, alongside a mouse colitis model induced by dextran sulfate sodium (DSS) administration. Intestinal barrier function was assessed by immunoblotting, immunofluorescence, in vitro permeability assays, and histopathological analysis. Mitochondrial integrity and function were evaluated using JC-1 staining and transmission electron microscopy. Additionally, key components of the aryl hydrocarbon receptor (AhR)/AMP-activated protein kinase (AMPK) signaling pathway were analyzed using immunoblotting, immunofluorescence, and immunoprecipitation techniques.

Results: Our findings demonstrate that IAld treatment significantly enhanced tight junction protein expression in intestinal epithelial cells and effectively attenuated TNF-α-induced intestinal barrier injury. IAld activated cellular AMPK signaling, promoting autophagy, maintaining mitochondrial homeostasis, and ultimately improving intestinal barrier function. Importantly, the activation of AMPK signaling by IAld was found to be dependent on the AhR, as evidenced by the AhR-specific inhibitor CH-223191, which abolished both IAld-induced AMPK activation and enhancement of intestinal barrier integrity. Furthermore, in vivo< experiments confirmed that IAld ameliorated intestinal barrier dysfunction and mitochondrial damage in DSS-induced colitis mice, whereas pharmacological inhibition of AMPK largely abrogated these protective effects.

Conclusion: Our findings demonstrate that IAld effectively preserves intestinal barrier integrity, highlighting its potential application in the treatment of intestinal inflammatory diseases in both animals and humans.

Objective: Fat deposition is an important factor that affects meat production and quality in livestock and poultry. Long non-coding RNAs (lncRNAs) play an important role in duck fat deposition. The purpose of this study was to identify key lncRNAs and mRNAs involved in fat deposition of meat ducks based on whole transcriptome sequencing for intramuscular preadipocyte (IMP-0), intramuscular adipocyte after 4 days of induction (IMP-4), subcutaneous preadipocyte (SCP-0), and subcutaneous adipocyte after 4 days of induction (SCP-4).

Methods: Differentially expressed mRNAs and lncRNAs were identified across groups through differential expression analysis, specific gene screening, and functional enrichment analysis. Subsequently, a lncRNA-mRNA co-expression network was constructed and key nodes were identified. Finally, preliminary expression validation was performed at the mRNA level.

Results: Differential expression analysis revealed 1,419 mRNAs and 697 lncRNAs in the IMP-0-vs-IMP-4 comparison, and 2,307 mRNAs and 1,180 lncRNAs in the SCP-0-vs-SCP-4 comparison. Venn analysis identified unique differentially expressed genes for each group, including CHKA, PNPLA2, PLPP1, FABP4, ACSL5, UGT8, FAT1, and FADS2. Functional enrichment showed that the IMP-0-vs-IMP-4 group was significantly associated with regulation of the MAPK cascade, lipid binding, and arachidonic acid metabolism. The SCP-0-vs-SCP-4 group was notably enriched in beta-alanine metabolism, the Wnt signaling pathway, and lipid metabolic processes. Co-expression network analysis further constructed a network of 193 nodes and 275 edges for the IMP-0-vs-IMP-4 group, and a larger network of 564 nodes and 3,471 edges for the SCP-0-vs-SCP-4 group. Key lncRNAs, such as MSTRG.8652.4, MSTRG.15586.1, and MSTRG.6393.1, were identified based on their high connectivity degree.

Conclusion: Taken together, the current findings indicated that there are differentially regulated differential genes, lncRNAs, and enrichment pathways in IMP-0-vs-IMP-4 and SCP-0-vs-SCP-4. Because of being differentially regulated, some differential factors were significantly increased in expression in intramuscular adipocyte induction while significantly downregulated in subcutaneous adipocyte induction, such as FABP3, MSTRG.13937.5, and MSTRG.6393.1. Meanwhile, there were also some factors that were specifically regulated, CHKA, PLA2G4A, FADS2, MSTRG.13842.1, MSTRG.16051.2 and MSTRG.13842.1 were significantly downregulated only in subcutaneous adipocytes. This suggests that these lncRNAs and their target genes may play important roles in intramuscular fat and subcutaneous fat deposition.

Objective: Livestock grazing is the primary practice in alpine meadows, which is closely related to animal performance and ecosystem functions. This study aimed to evaluate the effects of grazing practice on the growth performance, meat nutritional composition and shelf life, and fecal nutrient and microbiota of yaks.

Methods: Twenty-four male yaks (217.62±5.74 kg) were randomly divided into 2 groups for a 60 d fattening experiment: grazing (G) group and grazing and supplementary feeding (GS) group. The yaks in the G group were grazed only on pastures, without any supplements. The yaks in the GS group were not only grazed on natural pastures, also supplemented with the concentrate mix based on the body weight after grazing.

Results: Supplementary feeding concentrate mix after grazing significantly increased the body weight (p<0.01) and average daily gain (p<0.01) of yaks. The results indicated that supplementary feeding reduced meat shear force (p = 0.04), increased the a* value (p<0.01), the b* value (p = 0.04) and the ether extract content (p = 0.03), and extended the shelf life by 3.4 h. The total amino acid content increased (p<0.01) and promoted the deposition of monounsaturated fatty acids (p<0.01) and polyunsaturated fatty acids (p<0.01). The output concentration of nitrogen in feces was increased (p = 0.04), and the 16S rRNA sequencing results showed that grazing with supplementary feeding significantly increased the relative abundance of key genera, including Alistipes, UCG-009, Tuzzerella, Family_XIII_UCG-001, and Erysipelatoclostridium, which are associated with nutrient absorption, fiber degradation, and metabolism.

Conclusion: Post-grazing concentrate mix supplementation improved yak growth, meat quality, and shelf life, likely via enhanced amino acid and fatty acid deposition, nitrogen retention, and gut microbial shifts, which may ffers new insights into nutrient metabolism and feeding strategies for high-altitude livestock.

Objective: In China and Southeast Asia, black goats command higher selling prices. However, the blind breeding practices carried out by farmers pose a threat to the original genetic diversity of the population. Therefore, the objective of this study is to conduct a systematic detection of the genetic diversity of native black goat breeds, aiming to provide a reference for the protection and improvement of these valuable native black goat breeds.

Methods: Genetic diversity and population structure of 18 black goat breeds were estimated by utilizing 16 microsatellite markers. Subsequently, data analysis was carried out with the assistance of software like Phylip, Fstat, Arlequin, Structure. For the purpose of visualization, ITOL and Structure Selector were used to present the results in a visual manner.

Results: The mean number of alleles per population ranged from 4.75 to 9.56, with an average of 6.38. The observed heterozygosity of each breed ranged from 0.46 to 0.68, all of which were lower than the expected heterozygosity. The inbreeding coefficient (FIS) of the 18 breeds ranged from -0.003 to 0.376. Among them, the FIS values of Meigu goat (MG), Yimeng black goat, Yunling goat, Guizhou black goat and Ziwuling black goat were significantly higher than those under random rearrangement (p<0.05). All pairwise Fixation index between the Chinese black goat populations reached a significant level (p<0.05). Finally, the results of Bayesian model-based clustering and a neighbor-joining tree based on Nei's genetic distance showed these eighteen breeds can be further classified into seven genetic clusters.

Conclusion: All breeds showed high genetic diversity. MG had excessive inbreeding, and CZ and LZ were at risk of losing original genetic traits. Similar geographical and climatic conditions might lead to similar genetic materials in different breeds.

Objective: This study evaluated the effects of replacing soybean meal (SBM) with black soldier fly larvae (BSFL) in powdered and pelleted forms on feed intake, rumen fermentation, and nutrient digestibility in Thai native beef cattle.

Methods: Four male Thai native beef cattle (3-3.5 years old; 370±20.0 kg body weight) were assigned to a 4×4 Latin square design to evaluate the effects of replacing SBM with BSFL in the concentrate portion of the diet. The dietary treatments were: T1, control diet with SBM as the sole protein source; T2, 50% of SBM replaced with powdered BSFL; T3, 25% of SBM replaced with pelleted BSFL; and T4, 75% of SBM replaced with pelleted BSFL.

Results: Replacing SBM with BSFL had no significant effect on dry matter (DM) intake, ruminal pH, ammonia-nitrogen, or volatile fatty acid concentrations (p>0.05). Neutral detergent fiber intake was significantly higher in cattle fed the diet containing 75% pelleted BSFL compared to those fed 25% pelleted BSFL (p<0.01). Crude protein digestibility improved overall in BSFL-supplemented groups compared to the control (p<0.01). The highest DM digestibility was observed at 25% pelleted BSFL, significantly higher than at 75% inclusion (p<0.05). At 4 hours post-feeding, blood urea nitrogen concentration was significantly lower in cattle fed the 75% pelleted BSFL diet compared to those fed 25% pelleted BSFL (p<0.05). Protozoal populations, total volatile fatty acid concentrations, and the volatile fatty acid profile did not differ significantly among treatments (p>0.05).

Conclusion: Replacing SBM with BSFL, particularly at 25% in pelleted form, improves nutrient digestibility without impairing rumen fermentation, supporting its potential as a functional protein source in ruminant diets.