Animal Bioscience最新文献

Objective: High-ranking Hanwoo (Korean native cattle) semen produces calves with superior genetic ability that significantly enhances farm profitability. However, the repeated use of this semen can lead to reduced heterozygosity and genetic diversity within the Hanwoo population, which may compromise the accuracy in parentage verification. This study was conducted to analyze large-scale microsatellite (MS) marker data to evaluate the heterozygosity of Hanwoo cow and the discriminatory power of the MS marker set currently used for parentage verification.

Methods: The study population consisted of Hanwoo cows from farms participating in the Hanwoo cow improvement project, utilizing MS marker data from 778,544 heads collected for parentage verification since 2012. The observed heterozygosity (HObs), expected heterozygosity (HExp), polymorphism information content (PIC), and the inbreeding coefficient within populations (FIS) were estimated using R version 4.3.3 and Cervus version 3.0.7.

Results: As a result of the analysis, the average values of HObs, HExp, and PIC were 0.771, 0.768, and 0.736, respectively. Examining heterozygosity by marker according to birth year, variability gradually decreased in most markers after 2010. This is because after 2010, as the number of animals analyzed increased to over 10,000, the variance of sample statistics decreased, improving the accuracy of estimates. The estimated FIS values suggest that the population is approaching Hardy-Weinberg equilibrium and that the risk of inbreeding is being effectively managed through planned breeding programs. To assess temporal trends in genetic differentiation, we grouped individuals by birth year (2001 ~ 23) and calculated pairwise FST values. These values ranged from 0.0003 to 0.0081, indicating overall low levels of genetic differentiation and suggesting temporal genetic stability.

Conclusion: This study confirms that the Hanwoo population maintains high genetic diversity and low fixation, and that the currently used MS marker set remains robust and reliable for future parentage verification.

The black pigmentation trait in Taihe silky fowls results from melanin deposition produced by widely distributed melanocytes within their bodies. The degree of melanin deposition, termed melanization, not only determines their external characteristics but also critically influences their nutritional properties and medicinal value. Nutritionally, Taihe silky fowls with high melanization are rich in trace elements such as iron and zinc, along with various vitamins, conferring high nutritional value. Medicinally, according to traditional Chinese medicine theory, highly melanized Taihe silky fowls possess therapeutic effects including nourishing the liver and kidney, replenishing Qi, and enriching the blood. Specifically, they improve liver and kidney health, promote blood production and circulation, and enhance immune capacity. This paper comprehensively reviews the molecular mechanisms of melanin biosynthesis and deposition. It specifically analyzes how particular nutrients, including amino acids, vitamins, and minerals, regulate melanin deposition in Taihe silky fowls at the level of cellular pathways, while also discussing their appropriate dietary supplementation levels in production practices. The aim of this review is to deepen the understanding of the mechanisms underlying melanin trait formation in Taihe silky fowls and to provide theoretical support for the scientific optimization of their dietary nutritional formulations.

Objective: The Major Histocompatibility Complex (MHC) is central to immune defense. This study represents the first assessment of MHC-B haplotype diversity in Indonesian native chickens.

Methods: Six Indonesian native chicken populations were selected as study populations: Merawang (MRG), Pelung (PLG), Black Kedu (KJM), Sentul (STL), Nunukan (NNK), and Gaga (GAG); 24, 17, 30, 16, 14, and 20 birds from each population, respectively. Samples were genotyped using the MHC-B SNP panel. To explore haplotype diversity, the results were analyzed using PHASE 2.1 software.

Results: Genotyping of six Indonesian native chicken populations revealed high haplotype diversity, with a total of 126 distinct haplotypes: 38, 25, 19, 21, 11, and 12 from the MRG, PLG, KJM, STL, NNK, and GAG populations, respectively. Three haplotypes were shared: BSNP-IND14, shared by the KJM and STL populations; BSNP-IND26, shared by the KJM, NNK, and MRG populations; and BSNP-IND31, shared by the KJM and MRG populations. Accordingly, all the haplotypes obtained from the GAG and PLG populations were unique. Phylogenetic analysis of the results did not reveal a distinct pattern for each population; however, three subclades were identified, with all six populations represented in each clade. Comparison of MHC-B haplotypes in Indonesian native chickens with MHC-B standard haplotypes shows no distinct clades; however, three possible subclades were also identified. Nevertheless, no Indonesian MHC-B haplotypes matched 100% with the reported standard haplotypes, indicating that all Indonesian haplotypes identified in this study are novel. Furthermore, the comparison of Indonesian MHC-B haplotypes with those from other Asian regions reveals that the majority of Indonesian haplotypes cluster with those from Bangladesh, suggesting a shared evolutionary background among south and Southeast Asian chickens.

Conclusion: This study identified unique MHC-B haplotypes in Indonesian native chickens, suggesting that the observed populations are diverse in the MHC-B region and potentially have variation in immune responses.

Objective: Negative energy balance in transition cows elevates the circulating concentrations of non-esterified fatty acids (NEFA), which can trigger mastitis and pose a severe threat to the dairy industry. Resveratrol is a polyphenolic compound with anti-inflammatory properties, yet its role in NEFA-induced inflammation in bovine mammary epithelial cells (BMECs) remains unclear. This study aimed to investigate the protective effects of resveratrol on mastitis and elucidate its underlying mechanisms.

Methods: BMECs were pre-treated 100 µM RES for 24 h and then treated 0.9 mM NEFAs for 4 h, and a PINK1 inhibitor was used to assess the underlying mechanisms. Furthermore, a mouse model of mastitis was utilized to further evaluate the hepatoprotective effects of resveratrol against mastitis in vivo.

Results: Resveratrol significantly attenuated the NEFA-induced inflammatory response, as evidenced by reduced levels of NLRP3 inflammasome components (NLRP3, caspase1, IL-1β) and pro-inflammatory cytokines (IL-6, IL-1β and TNF-α). Mechanistically, resveratrol promoted mitophagy by upregulating levels of LC3-II, PINK1, and Parkin, and downregulating P62 expression. Crucially, the anti-inflammatory effect of resveratrol was reversed upon inhibition of PINK1. The in vivo experiments confirmed that resveratrol alleviated mammary gland inflammation and enhanced PINK1-mediated mitophagy.

Conclusion: This study demonstrates that resveratrol mitigates NLRP3-mediated inflammatory responses by activating PINK1-mediated mitophagy, suggesting its potential as a promising therapeutic candidate for mastitis in perinatal dairy cows experiencing negative energy balance.

This paper describes how animal management was done in the past and how we evolved to continuous animal monitoring by using technology. Based upon peer-reviewed literature, we show several technologies (cameras, microphones, sensors) developed and used for monitoring and managing indoor farm animals applied to different animal species: broilers, pigs, dairy cows, and horses. The main idea in developing precision livestock farming (PLF) technology is continuous 24/7 monitoring to generate objective data for farmers, veterinarians, and other stakeholders (pharma, feed company, equipment, climate control, etc.). Development started in laboratory settings and evolved to data collection in commercial farms. This paper shows that PLF monitoring allows us to measure objective data in each term of the fundamental process equation in producing animal products: the transfer from feed energy into animal product (meat, milk, eggs, fiber, and reproduction). The accuracies obtained are impressive in several examples. Regarding where to go with PLF, we show the great importance of animal welfare in the efficiency of the production process. Improving process efficiency is key in avoiding the need for even more farm animals to be slaughtered every year to fulfill the increasing worldwide demand for animal products. Field implementation of PLF technology for continuous objective measurements on indoor farm animals, to improve the efficiency of the production process, is an important contribution to feeding the worldwide increasing demand for animal products without a high increase of the number of farm animals.

Objective: This study investigated the role of ferroptosis, an iron-dependent form of regulated cell death, in meat quality by comparing the effects of pre-slaughter administration of teriflunomide, an inhibitor of dihydroorotate dehydrogenase (DHODH), which can induce ferroptosis, and dietary vitamin E, an antioxidant that can suppress ferroptosis, on the post-mortem biochemical properties of broiler chicken muscle.

Methods: Broiler chickens were randomly assigned to three groups: control, teriflunomide-treated, and vitamin E-supplemented. Teriflunomide was administered subcutaneously before slaughter, and vitamin E was provided in the diet. Post-mortem thigh muscles were analyzed for oxidative status such as lipid peroxide levels and the ratio of reduced to oxidized glutathione (GSH/GSSG); the expression of ferroptosis-related genes such as glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4); and meat quality traits such as pH, color, and water-holding capacity.

Results: Teriflunomide significantly decreased the GSH/GSSG ratio (p<0.001) and increased ACSL4 expression compared with the control and vitamin E groups (p<0.05), indicating elevated oxidative stress. Vitamin E significantly increased GPX4 expression compared with teriflunomide (p<0.05). Lipid peroxidation was numerically lower in the vitamin E group than in the other groups, although the differences were not statistically significant (p=0.062). Teriflunomide slowed post-mortem pH decline (p<0.001) and decreased L* and b* values, whereas a* values were higher (p<0.05). Vitamin E maintained higher L* and b* values and slightly lower a* values than the control (p<0.05). No statistically significant differences were observed in water-holding capacity among the groups.

Conclusion: These findings indicate that ferroptosis-related processes play a critical role in regulating post-mortem meat quality in broiler thigh muscles. DHODH inhibition by teriflunomide and antioxidant supplementation with vitamin E produced opposing effects.

Objective: This study was conducted to investigate the effect of age on eggshell color, Haugh unit and underlying mechanism in Hyline Brown laying hens.

Methods: A total of 192 Hyline Brown laying hens at 165 (D165 group), 307 (D307 group) or 475 (D475 group) day of age were divided into 3 groups with 8 replicates of 8 birds each, and fed the same diet for 3 weeks.

Results: Compared with the D165 group, the D307 and D475 group had higher (P < 0.05) eggshell L* value and yolk ratio but lower (P < 0.05) albumin ratio; the D475 group had higher (P < 0.05) eggshell b* value but lower (P < 0.05) albumin height, Haugh unit and eggshell a* value. The D165 group had higher (P < 0.05) eggshell protoporphyrin IX content and ovomucin content in eggs than the D307 and D475 group. The D165 group had higher (P < 0.05) total superoxide dismutase activity and glutathione content in eggshell gland than the D307 group. The malondialdehyde contents in serum, eggshell gland and magnum were higher in the D475 group than in the D165 group (P < 0.05). The D307 and D475 group had lower (P < 0.05) mRNA levels of genes related to pigment synthesis and transport (coproporphyrinogen oxidase, aminolevulinic acid synthase-1 and ATP-binding cassette subfamily G member 2) than the D165 group. The D475 group had lower (P < 0.05) mRNA levels of genes related to albumin synthesis (α-ovomucin and lysozyme) than the D165 and D307 group.

Conclusion: As hens aged, the deterioration of eggshell color and Haugh unit of eggs resulted from decreased gene expression and secretion of protoporphyrin IX and ovomucin, which might be due to increased lipid peroxidation in eggshell gland and magnum.

Objective: Microtubule dynamics regulator protein 2 (RMDN2) plays a crucial role in cell division, cytoskeleton maintenance, and various other cellular processes, establishing it as a candidate gene influencing chicken follicle development in our previous studies. This research aims to explore single-nucleotide polymorphisms (SNPs), perform phylogenetic analysis, and assess sequence characteristics of RMDN2, offering valuable insights for molecular marker-assisted breeding and enhancing the understanding of its regulatory mechanisms.

Methods: SNPs within the RMDN2 coding sequence (CDS) region were identified in an F2 resource population. Bioinformatics tools were employed to investigate the effects of SNP mutations on the structure and function of RMDN2 protein, and a phylogenetic tree was constructed to elucidate the potential mechanisms underlying the role of RMDN2 in chicken laying traits.

Results: Four novel exonic SNPs were discovered: SNP1 (c.250G>A, p.Val84Ile), SNP2 (c.270G>C, p.Lys90Asn), SNP3 (c.533G>T, p.Gly178Val), and SNP4 (c.606G>A). The heterozygous genotypes of SNP1, SNP3, and SNP4 were significantly associated with increased egg number at 66 weeks (EN66) (p < 0.05). In contrast, the heterozygous genotype of SNP2 is associated with higher body weight at first egg (BWFE) (p < 0.05). Notably, the H1H1 haplotype combination was associated with lower BWFE, body weight at 105 days (BW105), and first egg weight (FEW) (p <0.05). Missense mutations in SNP1, SNP2, and SNP3 were speculated to potentially influence the hydrophilic/hydrophobic properties, transmembrane regions, functional domains, and secondary structure of the RMDN2 protein, potentially reducing its stability. Phylogenetic analysis demonstrated 100% sequence homology between chicken and quail, with substantial conservation within species of the same order, but a marked decrease across different taxonomic orders.

Conclusion: These findings enrich the candidate gene pool for regulating chicken laying traits. However, further validation through in vivo and in vitro experiments remains necessary to strengthen the theoretical foundation for molecular breeding strategies.

Objective: We investigated the effect of reducing dietary crude protein (CP) and rumen degradable protein (RDP) while increasing rumen undegradable protein (RUP) on milk yield and composition, nitrogen (N) metabolism, and rumen and blood parameters in Holstein lactating cows.

Methods: Holstein cows (n = 13) were stratified by days in milk (91.75 ± 32.39), parity (2.58 ± 1.44), and milk yield (42.86 kg ± 6.6), and randomly assigned to one of two dietary groups (soybean meal (SBM) or heat-treated fermented soybean meal (HFSBM) group) in a completely randomized design.

Results: There were no differences in dry matter intake, milk production, milk composition (fat, protein, lactose, somatic cell count, β-hydroxybutyrate, and milk urea nitrogen). Ruminal ammonia concentrations were lower in the HFSBM group than in the SBM group. Ruminal total volatile fatty acid concentrations, acetate and propionate proportions, and blood urea nitrogen concentrations, did not differ. Calcium levels in the blood were lower both before feeding (0 h) and 3 h post-feeding in the HFSBM group compared to the SBM group. Total protein levels in blood were higher in the HFSBM group. There were no differences in digestibility of dry matter (DM) or CP, NDF. N outputs from feces and urine did not differ. Nitrogen efficiency tended to be higher in the HFSBM group.

Conclusion: Replacing SBM with HFSBM did not affect milk production but reduced ruminal ammonia concentrations, indicating that reducing dietary CP by increasing RUP levels can be implemented in dairy production without negatively impacting cow performance.

Objective: Acetyl-CoA synthetase 2 (ACSS2) is the obligatory gatekeeper for converting rumen-derived acetate into acetyl-CoA in ruminants. However, whether ACSS2 actively regulates the transcriptional networks governing lactation, beyond its catalytic role, remains unclear. This study aimed to elucidate the molecular characteristics of buffalo ACSS2 and investigate its function as a central node in the metabolic-transcriptional circuitry of buffalo mammary epithelial cells (BuMECs).

Methods: The complete coding sequence of buffalo ACSS2 was characterized, and its expression was analyzed across lactation stages. Subcellular localization was determined via high-resolution confocal microscopy. We utilized siRNA-mediated knockdown in BuMECs to assess cell viability, triglyceride (TAG) content, and the expression of core metabolic and regulatory genes to dissect the underlying molecular mechanisms.

Results: ACSS2 expression was highly enriched in lactating mammary tissue, and the protein exhibited a dual nucleocytoplasmic distribution. ACSS2 knockdown induced a "dual collapse" of cellular function: it severely impaired lipogenesis (significantly reducing intracellular TAG and downregulating FASN, ACACA, SCD, CD36, LPL, FABP3, DGAT1, DGAT2 and AGPAT6) and arrested cell proliferation (downregulating the G1/S phase regulators CCND1, CCNE1, CDK2 and CDK4). Mechanistically, ACSS2 depletion dismantled the transcriptional machinery itself, suppressing the mRNA levels of master regulators SREBF1 and PPARG. Crucially, this collapse was accompanied by the paradoxical upregulation of the SREBP1-inhibitor INSIG1, suggesting that metabolic stress triggers an INSIG1-mediated blockade of the feedback loop.

Conclusion: This study establishes ACSS2 as a critical metabolic checkpoint in the buffalo mammary gland, rather than a passive enzyme. We propose a model where ACSS2 maintains a reciprocal positive feedback loop with SREBP1 and PPARG. By ensuring sufficient acetyl-CoA to suppress INSIG1 and support histone acetylation (implied by nuclear localization), ACSS2 couples substrate availability to the stability of the lipogenic program and cell cycle progression. These findings reveal an evolutionarily conserved metabolic-epigenetic axis essential for high-efficiency lactation in ruminants.