A complete goat (Capra hircus) reference genome enhances analyses of genetic variation, thus providing insights into domestication and selection in goats and related species. Here, we assemble a telomere-to-telomere (T2T) gap-free genome (2.86 Gb) from a cashmere goat (T2T-goat1.0), including a Y chromosome of 20.96 Mb. With a base accuracy of >99.999%, T2T-goat1.0 corrects numerous genome-wide structural and base errors in previous assemblies and adds 288.5 Mb of previously unresolved regions and 446 newly assembled genes to the reference genome. We sequence the genomes of five representative goat breeds for PacBio reads, and use T2T-goat1.0 as a reference to identify a total of 63,417 structural variations (SVs) with up to 4711 (7.42%) in the previously unresolved regions. T2T-goat1.0 was applied in population analyses of global wild and domestic goats, which revealed 32,419 SVs and 25,397,794 SNPs, including 870 SVs and 545,026 SNPs in the previously unresolved regions. Also, our analyses reveal a set of selective variants and genes associated with domestication (e.g., NKG2D and ABCC4) and cashmere traits (e.g., ABCC4 and ASIP).

Jersey-yak is a hybrid offspring of Jersey cattle and yak (Bos grunniens). Changing the feeding system of Jersey-yak can significantly improve its growth performance. In this study, tandem mass tag (TMT) proteomics technology was used to determine the differentially expressed proteins (DEPs) of the longissimus lumborum (LL) muscle of Jersey-yak fed different protein levels of diet. The results showed that compared with the traditional grazing feeding, the growth performance of Jersey-yaks was significantly improved by crude protein supplementation after grazing. A total of 3368 proteins were detected in these muscle samples, of which 3365 were quantified. A total of 434 DEPs were identified. Through analyses, it was found that some pathways related to muscle growth and development were significantly enriched, such as Rap1 signaling pathway, mTOR signaling pathway, and TGF-beta signaling pathway. A number of DEPs enriched in these pathways are related to muscle cell development, differentiation, and muscle development, including integrin subunit alpha 7 (ITGA7), myosin heavy chain 8 (MYH8), and collagen type XII alpha 1 chain (COL12A1). In conclusion, the results of this study provide insights into the proteomics of different feeding patterns of Jersey-yak, providing a stronger basis for further understanding the biological mechanism of hybrid varieties.

Traditional fermented yak milk has immense cultural and nutritional significance for Tibetan herders. In this study, we investigated the microbial community structure and flavour compounds in traditional fermented yak milk from three distinct regions of Gannan to explore the relationship between microbial composition and flavour compounds. The findings revealed significant variations in flavour compounds and the bacterial microbiota among the samples from the three regions. The dominant species identified in fermented yak milk were Streptococcus salivarius subsp. Thermophilus, Lactobacillus helveticus, and Kluyveromyces marxianus. Bidirectional orthogonal partial least-squares (O2PLS) analysis highlighted five bacterial genera and three fungal genera as contributors to the production of flavour-related compounds. Furthermore, regression analysis revealed that the Lactobacillus and Streptococcus genera were associated with the production of 2,3-pentanedione as well as eight predicted KEGG pathways. These findings provide valuable insights into the intricate relationship between flavour compounds and microbiota in traditional fermented yak milk.

This study aimed to investigate the microbial community structure and flavor compounds, including amino acids, fatty acids, and volatile compounds in traditional fermented yak milk from three distinct regions of Gannan, as well as their relationship. The findings revealed significant variations in flavor compounds, particularly amino acids among the three regions. Similar with the variation in flavor profile, there was also a significant variation in bacterial microbiota among the three regions. The dominant species were identified as Streptococcus salivarius subsp. Thermophiles, Lactobacillus helveticus and Kluyveromyces marxinu, Tausania pullulans in fermented yak milk. Bidirectional orthogonal partial least squares identified five bacterial and three fungi genera as contributors to flavor production, including ethyl acetate and some fatty acids. Furthermore, through regression analysis, we associated the genera of Lactobacillus and Streptococcus with 2,3-pentanedione via 8 KEGG pathways predicted by PICRUST2, such as fatty acid biosynthesis, pentose phosphate, and Alanine, aspartate and glutamate metabolism.

Introduction:The crude protein level in the diet will affect the fermentation parameters, microflora, and metabolites in the rumen of ruminants. It is of great significance to study the effect of crude protein levels in supplementary diet on microbial community and metabolites for improving animal growth performance. At present, the effects of crude protein level in supplementary diet on rumen fermentation parameters, microbial community, and metabolites of Jersey-Yak (JY) are still unclear. Methods:The purpose of this experiment was to study the appropriate crude protein level in the diet of JY. The rumen fermentation indexes (volatile fatty acids and pH) were determined by supplementary diets with crude protein levels of 15.16 and 17.90%, respectively, and the microbial community and metabolites of JYs were analyzed by non-target metabonomics and metagenome sequencing technology, and the changes of rumen fermentation parameters, microbial flora, and metabolites in the three groups and their interactions were studied. Results and Discussion:The crude protein level in the supplementary diet had significant effects on pH, valeric acid, and the ratio of acetic acid to propionic acid (p < 0.05). The protein level had no significant effect on the dominant microflora at the phylum level (p > 0.05), and all three groups were Bacteroides and Firmicutes. The results of metabolite analysis showed that the crude protein level of supplementary diet significantly affected the metabolic pathways such as Bile secretion and styrene degradation (p < 0.05), and there were different metabolites between the LP group and HP group, and these different metabolites were related to the dominant microbial to some extent. To sum up, in this experiment, the effects of crude protein level in supplementary diet on rumen microorganisms and metabolites of JY and their relationship were studied, which provided the theoretical basis for formulating a more scientific and reasonable supplementary diet in the future.

The present study aimed to characterize the influence of hypoxia-inducible factor-1α on heat shock protein 27 and cytochrome c translocation, yak meat microstructure destruction, and endogenous enzymes activities, refining the understanding of the tenderization process after slaughter. Postmortem yak longissimus thoracis et lumborum muscles were incubated with 0.9% saline or hypoxia-inducible factor-1α stabilizer dimethyloxaloylglycine at 4 °C for 6, 12, 24, 72, and 120 h. Results showed that hypoxia-inducible factor-1α activation promoted heat shock protein 27 migration and cytochrome c release, facilitating (P < 0.05) caspase-3 activity by mediating the heat shock protein 27/caspase-3 interaction but did not exert (P > 0.05) significant effects on the calpain-1 activity. Additionally, hypoxia-inducible factor-1α activation contributed to the mitochondrial apoptosis cascade, leading to a higher (P < 0.01) apoptosis rate. Therefore, these observations indicate that hypoxia-inducible factor-1α affects caspase-3 activity and tenderness of postmortem muscle through distinct regulatory mechanisms, possibly, in part, with heat shock protein 27 and cytochrome c mediation.

[目的]测量甘南牦牛二元、三元杂交后代周岁内生长发育情况,分析杂交利用方向.[方法]根据牧区草原畜牧业季节性特点,测量了二元、三元杂交后代初生(0月龄)、8月龄和12月龄体尺体重,对比分析不同杂交组合在不同生长阶段的生长发育情况.[结果]不论是二元杂交还是三元杂交,杂交后代均表现出良好的杂交优势,优良品种杂交后代生长发育极显著优于本地品种;安格斯尕力巴牛在8月龄,娟犏牛在12月龄体重达到100 kg以上,可为高原犊牛肉的生产提供优质牛源.

本文结合甘南州草原畜牧业发展现状,阐述了科技示范在草原畜牧业发展中的引领作用,并探讨了甘南州畜牧业发展中还需科学技术解决的难题.

The Jeryak is the hybrid offspring of yaks and Jersey cattle and exhibit improved milk and meat yields. Biomolecules carried within milk exosomes are important for cell growth, development, immune regulation, and various pathophysiological processes. Previous studies showed that miRNAs regulate mammary gland development, lactation, and milk quality. This study explored the relationship between milk exosomes miRNAs and lactation performance. A comparison of the milk content showed that yak milk was of a better quality compared to Jeryak milk (casein, fat, TS, SNF, lactose). Milk collected in December was superior to that collected in June for both yak and Jeryak, except for lactose concentrations. Exosomes were extracted by density gradient centrifugation and miRNA expression profiles in milk exosomes from three yaks and three Jeryaks collected in June and December were detected by small RNA sequencing. In all, 22, 120, 78, and 62 differentially expressed miRNAs (DEMs) were identified in Jun_ JY vs. Jun_ Y (P1: Jeryak in June vs. Yak in June), Jun_ JY vs. Dec_ JY (P2: Jeryak in June vs. Jeryak in December), Dec_ JY vs. Dec_ Y (P3: Jeryak in December vs. Yak in December), and Jun_ Y vs. Dec_ Y (P4: Yak in June vs. Yak in December) groups. These DEMs were enriched in functions and signaling pathways related to lactation performance. In conclusion, these findings are a reference tool to study the molecular basis of lactation performance.

[目的]探索欧拉型藏羊解偶联蛋白2(UCP2)和解偶联蛋白3(UCP3)基因的多态性及其与生长性状的关联性,为运用分子标记辅助育种方法提高欧拉型藏羊的生长性状提供理论依据.[方法]以239头成年欧拉型藏羊为试验对象,采用PCR产物直接测序技术检测UCP2和UCP3基因的遗传多态性,并将其与体质量、体高、体斜长和胸围生长性状进行关联性分析.[结果]在欧拉型藏羊UCP2基因上筛选出2个SNPs位点,分别为g.52130414 C＞T 和 g.52130584 G＞A,其中 g.52130414 C＞T 位点产生 TT、CT 和 CC 3 种基因型,g.52130584 G＞A 位点产生AA、AG和GG 3种基因型;在UCP3基因上筛选出1个SNP位点g.52157335 C＞T,产生CC、CT和TT 3种基因型.基因多态性分析表明,3个SNPs位点均为错义突变位点,属于中度多态,且均符合Hard-Weinberg平衡适应性检验(P＞0.05).关联分析结果显示,UCP2基因g.52130414 C＞T位点TT基因型欧拉型藏羊体质量显著高于CT基因型(P＜0.05);g.52130584 G＞A位点AA基因型欧拉型藏羊体质量和体斜长均极显著高于AG和GG基因型(P＜0.01),AA和GG基因型欧拉型藏羊胸围均显著高于AG基因型(P＜0.05);UCP3基因g.52157335 C＞T位点CC基因型欧拉型藏羊体质量显著高于CT基因型(P＜0.05),TT基因型欧拉型藏羊胸围显著高于CT基因型(P＜0.05).3个多态位点基因型组合分析发现,5个发生频率较高的双倍型中,D5型欧拉型藏羊体质量极显著高于D1、D2、D3型(P＜0.01),体高显著高于D3型(P＜0.05),体斜长显著高于D1、D3、D4型(P＜0.05)且极显著高于D2型(P＜0.01).[结论]UCP2和UCP3基因多态性与欧拉型藏羊的部分生长性状显著相关,UCP2和UCP3基因可作为欧拉型藏羊生长性状选育的候选基因.D5双倍型为优势基因型,可在选育工作中优先考虑.

The Qinghai-Tibetan Plateau offers one of the most extreme environments for yaks (Bos grunniens). Although the genetic adaptability of yak and rumen metagenomes is increasingly understood, the relative contribution of host genetics and maternal symbiotic microbes throughout early intestinal microbial successions in yaks remains elusive. In this study, we assessed the intestinal microbiota succession of co-inhabiting yak and cattle (Bos taurus) calves at different weeks after birth as well as the modes of transmission of maternal symbiotic microbes (i.e., rumen fluid, feces, oral cavity, and breast skin) to their calves’ intestinal microbiota colonization. We found that the fecal microbiota of yak and cattle calves after birth was dominated by members of the families Ruminococcaceae, Bacteroidaceae, and Lachnospiraceae. The Source Tracker model revealed that maternal fecal microbes played an important role (the average contribution was about 80%) in the intestinal microbial colonization of yak and cattle calves at different weeks after birth. Unlike cattle calves, there was no significant difference in the fecal microbiota composition of yak calves between 5 and 9 weeks after birth (Wilcoxon test, P > 0.05), indicating that yak may adapt to its natural extreme environment to stabilize its intestinal microbiota composition. Additionally, our results also find that the intestinal microbial composition of yak and cattle calves, with age, gradually tend to become similar, and the differences between species gradually decrease. The findings of this study are vital for developing strategies to manipulate the intestinal microbiota in grazing yaks and cattle for better growth and performance on the Qinghai-Tibetan Plateau.

通过对燕麦栽培环境条件、种子处理、施肥、播种和收获等田间控制关键技术的规范,为高寒地区建植和管理高产优质人工草地提供技术支撑,引导区域经济发展.

以3岁的盘羊与欧拉羊杂交一代、欧拉羊为对象,研究杂交效果的优劣并进行评价.选择10只羊进行屠宰试验,检测其屠宰性能和肉品质;使用仪器测定其氨基酸、脂肪酸及风味成分.结果表明,盘羊×欧拉型杂交F1宰前活质量与欧拉型藏羊差异显著,胴体质量、屠宰率、眼肌面积差异不显著;盘羊×欧拉型杂交F1的GR值、失水率和熟肉率略优于欧拉型藏羊;组氨酸和半胱氨酸含量差异显著,其余氨基酸含量差异不显著;盘羊×欧拉型杂交F1的单不饱和脂肪酸及多不饱和脂肪酸含量均高于欧拉型藏羊;两者检测均发现34种风味物质,含量差异不大.综上,盘羊×欧拉型杂交F1在屠宰性能、肉品质、脂肪酸成分及构成比例等方面都表现出良好的肉品品质.

随着畜牧业的发展,饲料资源短缺、环境污染等问题日益突出,因此提高饲料资源的消化率成为加快畜牧业发展的关键性问题.研究表明,益生菌具有调节胃肠道微生物群落及其活动的能力,提高反刍动物的代谢水平和营养物质的利用率.益生菌在增强机体的免疫功能和抗病能力以及减少养殖过程中甲烷排放等方面发挥重要作用.本文综述了反刍动物饲粮中添加益生菌对瘤胃微生物及生产性能的积极影响,以期为益生菌在反刍动物健康养殖中应用提供理论依据.

Although exhaustive studies have established that oxidative stress is a key contributor to accelerated postmortem metabolism, the specific reasons remain fully undefined. We hypothesized that nuclear accumulation of hypoxia-inducible factor-1α (HIF-1α), a significant transcription factor for energy metabolism, regulates postmortem glycolysis under oxidative stress. Postmortem yak longissimus dorsi (LD) muscles were incubated with saline, hydrogen peroxide (H2O2), H2O2 plus MAPK/ERK inhibitor (U0126), or H2O2 plus U0126 and HIF-1α activator, dimethyloxalylglycine (DMOG), respectively. Changes in HIF-1α, MAPK/ERK signaling pathway, and postmortem metabolism levels were measured in muscles collected from all time points. Oxidative stress significantly activated MAPK/ERK pathway and increased HIF-1α expression and nuclear translocation (P < 0.05) although its mRNA levels were hardly affected (P > 0.05). Additionally, oxidative stress enhanced early postmortem muscle metabolism (P < 0.05). These effects were substantially weakened by U0126 treatment, which prevented oxidative stress-induced HIF-1α accumulation and glycolysis. Interestingly, this attenuation could be bypassed by DMOG (P < 0.05). Altogether, MAPK/ERK-dependent maintenance and enhancement of HIF-1α nuclear accumulation promotes postmortem metabolism during early postmortem under oxidative stress. These findings provide valuable information on postmortem metabolism that HIF-1α regulates glycolysis under oxidative stress and suggest that HIF-1α can serve as a target for controlling postmortem glycolysis.

The perinatal period has an important impact on the health of ruminants, and the imbalance of udder skin microbiota might be an important inducement of bovine mastitis. However, it is not clear how the perinatal period affects the microbial structure and stability of the udder skin of yak and cattle. Here, we used 16S rRNA gene high-throughput sequencing to analyze the udder skin microbiota of yak and cattle during the perinatal period. We found that the diversity and richness of microbiota of bovine udder skin during 1-2 weeks postpartum were significantly lower than those in the 1-2 weeks prenatal and 1-month postpartum period (Wilcoxon, p < 0.05). Besides, we found sharing of 2,533 OTUs in the udder skin microbiota of yak and cattle during the perinatal period, among which the core microbiota at the genera level was mainly composed of Staphylococcus, Moraxella, and Acinetobacter. However, the genus Acinetobacter was significantly abundant in the udder skin of cattle during 1-2 weeks postpartum. The NMDS and LEfSe results showed that the perinatal period had more effects on the composition and stability of microbial community in the udder skin of cattle compared to yak, particularly during 1-2 weeks postpartum. In addition, the average content of total whey proteins and immunoglobulin G of whey protein were significantly higher in the yak colostrum when compared to those found in the cattle (p < 0.05). In conclusion, the structure of udder skin microbiota of yak during the perinatal period is more stable than that of cattle in the same habitat, and 1-2 weeks postpartum may be a potential window period to prevent cattle mastitis.

Understanding the genetic mechanisms of phenotypic variation in hybrids between domestic animals and their wild relatives may aid germplasm innovation. Here, we report the high-quality genome assemblies of a male Pamir argali (O. ammon polii, 2n = 56), a female Tibetan sheep (O. aries, 2n = 54), and a male hybrid of Pamir argali and domestic sheep, and the high-throughput sequencing of 425 ovine animals, including the hybrids of argali and domestic sheep. We detected genomic synteny between Chromosome 2 of sheep and two acrocentric chromosomes of argali. We revealed consistent satellite repeats around the chromosome breakpoints, which could have resulted in chromosome fusion. We observed many more hybrids with karyotype 2n = 54 than with 2n = 55, which could be explained by the selfish centromeres, the possible decreased rate of normal/balanced sperm, and the increased incidence of early pregnancy loss in the aneuploid ewes or rams. We identified genes and variants associated with important morphological and production traits (e.g., body weight, cannon circumference, hip height, and tail length) that show significant variations. We revealed a strong selective signature at the mutation (c.334C > A, p.G112W) in TBXT and confirmed its association with tail length among sheep populations of wide geographic and genetic origins. We produced an intercross population of 110 F2 offspring with varied number of vertebrae and validated the causal mutation by whole-genome association analysis. We verified its function using CRISPR-Cas9 genome editing. Our results provide insights into chromosomal speciation and phenotypic evolution and a foundation of genetic variants for the breeding of sheep and other animals.

Cattle-yak is a hybrid F1 generation of cattle and yak, which has a history of more than 3000 years and has shown better production performance and higher economic benefits than those of yaks. However, up to now, there has been no study on the transcriptome-wide m6A methylation profile of bovine skeletal muscle and its potential biological function during muscle development. Here, we observed significant changes in the expression levels of muscle-related marker genes and methylation-related enzymes during the development of cattle-yak, and the overall m6A content in the Longissimus dorsi muscle of 18-month-old cattle-yak decreased significantly. A total of 36,602 peaks, 11,223 genes and 8388 lncRNAs were identified in the two groups, including 2989 differential peaks (427 up-regulated peaks and 2562 down-regulated peaks), 1457 differentially expressed genes (833 up-regulated genes and 624 down-regulated genes) and 857 differentially expressed lncRNAs (293 up-regulated lncRNAs and 564 down-regulated lncRNAs). GO and KEGG analysis revealed that they were significantly enriched in some muscle-related pathways (Wnt signaling pathway and MAPK signaling pathway) and high-altitude adaptation-related pathway (HIF-1 signaling pathway). Moreover, m6A abundance was positively correlated with gene expression levels, while it was negatively correlated with lncRNA expression levels. This indicates that m6A modification played an important role in the Longissimus dorsi muscle development of cattle-yak; however, the regulation mechanism of m6A-modified mRNA and lncRNA may be different. This study was the first report of transcriptome-wide m6A-modified mRNAs and lncRNAs atlas in the Longissimus dorsi muscle development of cattle-yak, one which will provide new perspectives for genetic improvement in bovines.

对合作猪选育群的建立、选育方法、种猪鉴定、后备种猪的选择、种猪淘汰、饲养管理以及选育资料记录等进行阐述,以期规范合作猪选育技术,提高品种整体质量,指导生产.

为了解甘南牦牛主产地土壤—牧草—水系统矿物质元素含量的特征,选取甘肃省甘南藏族自治州玛曲县阿万仓乡阿孜畜牧科技示范园区和碌曲县尕海镇尕秀村各3个放牧代表性地段,每个地段随机布设3个1.0 m×1.0 m样方采集牧草、土壤混样,并收集其周围河流的水样,对所采牧草、土壤、水样进行了检测.结果表明,玛曲县牧草粗蛋白含量12.95％、粗脂肪含量19.67 g/kg、粗纤维含量14.60％,碌曲县牧草粗蛋白含量8.86％、粗脂肪含量17.00 g/kg、粗纤维含量16.60％,两地牧草富含钾、铁、钙等矿物质元素,但均缺硒;玛曲县土壤pH值5.76,碌曲县土壤pH值6.34,玛曲县土壤中钾、钙、铁、镁、锌等微量元素的含量均高于碌曲县;两地水质相似,均为弱碱性,碌曲县水中的钠、钙、镁含量较高,玛曲县水中的钾含量较高,两地牧草、土壤、水中重金属含量均符合国家标准要求.