White Yak Research Articles

Molecular characterization and expression profile of the melatonin receptor MT1 in the ovary of Tianzhu white yak (Bos grunniens)

Melatonin plays crucial roles in a wide range of ovarian physiological functions via the melatonin receptors (MRs). Structure and function of MRs have been well studied in sheep, cattle, and humans, but little information exists on the genetic characterization and function of these receptors in the ovary of the white yak. In the present study, the melatonin receptor MT1 was cloned by RT-PCR in the ovary of white yak; the MT1 cDNA fragment obtained (843bp) comprised an open reading frame (827bp) encoding a protein containing 275 residues, characterized by seven transmembrane regions and an NRY motif, two distinct amino acid replacements were found. The white yak MT1 had a 83.9–98.6% protein sequence identity with that of nine other mammals. Using RT-PCR, the expression levels of MT1, MT2, and LHR in the ovary of pregnant and non-pregnant white yaks were compared, revealing higher levels of all genes in pregnant yaks: 3.83-fold increase for MT1 (P<0.05), 1.39-fold increase for MT2, and 15.32-fold increase for LHR (P<0.05). The distribution of MT1 in yak ovaries was observed using immunohistochemistry on paraffin embedded ovarian sections: MT1 was mainly present on primordial follicles (PF), granulosa cells (GCs), oocytes, and corpus luteum (CL) cells; MT1 expression showed an increasing tendency from PF to GCs to oocytes and to large CL cells. It is suggested that melatonin and MT1 are associated with the corpus luteum function of pregnancy maintenance and follicular development during oocyte maturation in the white yak.

Seroprevalence, risk factors and genetic characterization of Toxoplasma gondii in free-range white yaks (Bos grunniens) in China

The objective of this study was to determine the seroprevalence, risk factors and genotypes of Toxoplasma gondii in white yaks (Bos grunniens) in China. A total of 974 serum samples were collected from white yaks in Tianzhu Tibetan Autonomous County (TTAC), Gansu province, northwest China for detecting T. gondii antibodies by the modified agglutination test (MAT), and 414 tissues belonging to 138 white yaks were collected for detecting T. gondii DNA by amplification of B1 gene with a semi-nested PCR. A total of 155 serum samples (15.91%) were seropositive for T. gondii antibodies at a 1:100 cut-off, and 10 DNA samples (7.25%) were positive for the T. gondii B1 gene, which were genetically characterized using multilocus PCR-RFLP. Only one genotype (ToxoDB#9) was identified from two samples with complete genotyping results. Statistically significant differences were not observed between T. gondii seroprevalence and gender, season or pregnancy in the logistic regression analysis (P>0.05). Ages of white yaks was considered as a main risk factor associated with T. gondii infection. Our results indicated a widespread exposure to T. gondii among white yaks, and revealed the genotype ToxoDB#9 of T. gondii in white yaks for the first time in China.

Novel SNP of EPAS1 gene associated with higher hemoglobin concentration revealed the hypoxia adaptation of yak (Bos grunniens)

Endothelial PAS domain protein 1 gene (EPAS1) is a key transcription factor that activates the expression of oxygen-regulated genes. In this study, in order to better understand the effects of EPAS1 gene on hematologic parameters in yak, we firstly quantified the tissue expression patterns for EPAS1 mRNA of yak, identified polymorphism in this gene and evaluated its association with hematologic parameters. Expression of EPAS1 mRNA was detected in all eight tissues (heart, liver, lung, spleen, pancreas, kidney, muscles and ovary). The expressions of EPAS1 in lung and pancreas were extremely higher than other tissues examined. Three novel single nucleotide polymorphisms (SNPs) (g.83052 C>T, g.83065 G>A and g.83067 C>A) within the EPAS1 were identified and genotyped in Pali (PL), Gannan (GN) and Tianzhu White (TZW) yak breeds. Significant higher frequencies of the AA and GA genotypes and A allele of the g.83065 G>A were observed in the PL and GN breeds than that in the TZW breed (P<0.01). Association analysis of the PL breed indicated that the g.83065 G>A polymorphism was significantly associated with hemoglobin (HGB) concentration in yaks (P<0.05). Individuals with genotype AA had significantly higher HGB concentration (P<0.05) than those with genotype GA and GG. All these results will help our further understanding of biological functional of yak EPAS1 gene in responding to hypoxia and also indicate EPAS1 might contribute to the hypoxia adaptation of the yak.

First report of Babesia bigemina infection in white yaks in China

White yaks, a unique yak breed and the pearl of the plateau, only live in Tianzhu Tibetan Autonomous County (TTAC), Gansu Province, northwest China, contributing significantly to local economy. However, there was no information on the prevalence of Babesia bigemina in white yaks. In this study, a total of 974 serum samples collected from white yaks in TTAC were examined for specific antibodies against B. bigemina using a commercially available ELISA kit. The overall seroprevalence of B. bigemina in white yaks was 17.76% (173/974). A multivariate logistic regression analysis was performed to determine the risk factors associated with B. bigemina seroprevalence, and the results indicated that age, gender and the numbers of pregnancies of white yaks were not the significant risk factors. However, the white yaks in spring (OR=3.523, 95% CI=1.899–6.538, P<0.001) and summer (OR=3.439, 95% CI=1.909–6.193, P<0.001) encountered higher risk of being exposed to B. bigemina than that in winter. Thus, season was considered as a risk factor associated with B. bigemina infection. This is the first survey of B. bigemina seroprevalence in white yaks in China, which extends the host range for B. bigemina and provides useful information for controlling B. bigemina infection in white yaks.

Seroprevalence and risk factors of Chlamydia abortus infection in free-ranging white yaks in China

BackgroundChlamydia is gram-negative obligate bacteria which causes a wide variety of diseases in humans and animals. To date, there are a few reports about the seroprevalence of Chlamydia and the risk factors associated with Chlamydia infection in yaks in the world. In this study, 974 blood samples were collected from white yaks (Bos grunniens) in Tianzhu Tibetan Autonomous County, Gansu province, northwest China from June 2013 to April 2014.ResultsAntibodies against Chlamydia abortus were examined by the indirect hemagglutination (IHA) test, and 158 of 974 (16.22%) white yaks were seropositive for C. abortus antibodies at the cut-off of 1:16. The risk factors associated with seroprevalence were evaluated by a multivariate logistic regression analysis. Region, gender and age of white yak were left out of the final model, due to its insignificance in the logistic regression analysis (P > 0.05). However, season was considered as a major risk factor associated with C. abortus infection in white yaks.ConclusionsTo our knowledge, this is the first survey of C. abortus seroprevalence in white yaks in China, which extends the host range for C. abortus and has important implications for public health and the local Tibetan economy.

Brief Note :Variability in the cathelicidin 6 (CATHL-6) gene in Tianzhu white yak from Tibetan area in China.

Cathelicidins are a major family of antimicrobial peptides (AMPs), an important component of innate immune system, playing a critical role in host defense and disease resistance in virtually all living species. Polymorphism and functional studies on cathelicidin of Tianzhu white yak contribute to understanding the specific innate immune mechanism in animals living at high altitudes in comparison to cattle and domesticated white yak. Thirty-six individuals of Tianzhu white yak, originating from the area of three ecotypes (Gansu in China), were investigated. The total length of the aligned Yak cathelicidin 6 (CATHL-6) sequences was 1923 bp, including six single nucleotide polymorphisms and one indel. Ten haplotypes were identified, and phylogenetic analyses resolved those 10 haplotypes in two clusters. The results indicate that the white yak originated from two domestication sites. In addition, lack of significant pairwise difference between sequences (Tajima's D = 0.92865, P > 0.10) in the CATHL-6 region indicates absence of population size expansion in current white yak population.

The melatonin receptor in the bactrian camel pineal: cloning experiments and distribution studies

The aim of this study was to identify the high-affinity melatonin-receptor subtypes expressed in pineal of camel. To achieve this, reverse transcription-polymerase chain reaction (RT-PCR), sequencing and immunohistochemistry were used. By using RT-PCR, mRNA of melatonin receptors MT1/MT2 were detected in the pineal of bactrian camel. The highest identity was 87.2% and 97.6%, respectivly for MT1 and MT2 compatively with white yak. The pridict protein of the deduce amino acid sequence showed a tendency towards forming the 7-TM motif profile of G-protein. The immunohistochemistry studies showed that melatonin receptors are expressed in pinealocytes and glial cells of pineal. Overall, these results showed that melatonin receptors are expressed in the bactrian camel pinealocytes, and melatonin, possible as intracrine or autocrine, can influence pinealocytes and pineal physiological function.

Phylotaxonomic position of Tianzhu white yak (Poephagus grunniens) based on nucleotide sequences of multiple subunits of cytochrome c oxidase

To estimate the phylotaxonomic position of Tianzhu white yak (Poephagus grunniens), multiple subunit genes of cytochrome c oxidase (cox) were sequenced: 1545 bp of cox1 (JF946751), 684 bp of cox2 (JN008944) and 781 bp of cox3 (JF946752). Sequence divergences of cox genes between yaks and cattle/zebus (5.7% in cox1, 7.7% in cox2 and 6.45% in cox3) were higher than those between yaks and American bisons (2.4% in cox1, 3.0% in cox2 and 2.1% in cox3). Molecular phylogenetic analysis with these genes also found that yaks and American bisons firstly clustered in one clade, indicating there was higher genetic comparability than that of cattle/zebus. The findings sustained the idea that in the choice of nomenclature yaks belong to the subgenus of Poephagus. According to the nucleotide substitution rate of cox genes among species of Bovinae, the speculated divergence time of yaks from cattle/zebus, American bisons, European bisons, Asian buffaloes/African buffaloes was 1.05–1.50 million years ago (MYA), 2.85–3.89 MYA, 2.90–3.70 MYA, 6.85–7.50 MYA, respectively. The sequential evolution of Bovinae members could be predicted that buffaloes were first to be domesticated during the end of Miocene and the early of Pliocene. In the end of Pliocene, the Bovinae genera were evolved to Bos, Bison and Poephagus. Poephagus was the latest evolved genera among the species of Bovinae.

Complete mitochondrial genome of the a rare subspecies of genus Bos, Tianzhu white yak from Tibetan area in China

The population of domestic yak, Tianzhu white yak, from Tibetan area in China is considered as a rare Bos grunniens species. We first determined and annotated its complete mitochondrial genome. The mitogenome is 16,319 bp in length, consisting of 13 protein-coding genes, 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and a control region. As in other mammals, most mitochondrial genes are encoded on the heavy strand, except for ND6 and eight tRNA genes, which are encoded on the light strand. Its overall base composition is A: 33.7%, T: 27.2%, C: 25.8% and G: 13.2%. The complete mitogenome of the new subspecies of Bos grunniens could provide an important data to further explore the taxonomic status of the subspecies.

First report of Cryptosporidium spp. in white yaks in China.

BackgroundCryptosporidium is an enteric apicomplexan parasite, which can infect yaks, leading to reduction of milk production and poor weight gain. White yak (Bos grunniens) is a unique yak breed inhabiting only in Tianzhu Tibetan Autonomous County, Gansu province, northwestern China. The objective of the present study was to molecularly determine Cryptosporidium infection and species in white yaks.FindingsSeventy-six fecal samples from white yaks in Tianzhu Tibetan Autonomous County, Gansu province were collected. The small subunit ribosomal RNA (SSU rRNA) gene of each sample was amplified using nested PCR and sequenced. The Cryptosporidium species was determined by comparison of the obtained sequences with that of corresponding Cryptosporidium sequences available in GenBank by BLAST (http://www.ncbi.nlm.nih.gov/BLAST/) and phylogenetic analysis with maximum likelihood (ML) using PAUP*. The overall prevalence of Cryptosporidium infection in white yak was 5.26% (4/76). Species identification showed C. andersoni in one sample (collected in September), and C. bovis in three samples (one collected in November and two collected in September).ConclusionsThe present investigation revealed the existence of Cryptosporidium infection in white yaks in China, for the first time, and two Cryptosporidium species, namely C. andersoni and C. bovis, were identified. These findings extend the host range for Cryptosporidium spp., and also provide base-line information for further studies of molecular epidemiology and control of Cryptosporidium infection in the unique white yaks.

Proteomic Analysis of the Follicular Fluid of Tianzhu White Yak during Diestrus

The aim of this study was to identify differentially expressed proteins in the follicular fluid of Tianzhu white yak during diestrus. Follicles obtained from female yak were divided into four groups according to their diameter: 0–2, 2–4, 4–6 mm, and greater than 6 mm. The follicular fluid was directly aspirated from the follicles and mixed according to follicular size, and two-dimensional gel electrophoresis was carried out on the crude follicular fluid samples. Thirty-four differentially expressed spots were generated from these four sizes of follicles. Fourteen of these spots were analyzed by MALDI-TOF/TOF-MS and identified as: AS3MT, VDP, ANKRD6, C10orf107 protein, MRP4, MAPKAP1, AGO3, profilin-β-actin, SPT2 homolog, AGP, AR, RNF20, obscurin-like-1, and one unnamed protein. These proteins were first reported in follicular fluid, in addition to VDP and AGP. Based on existing knowledge of their function and patterns of expression, we hypothesize that most of these differentially expressed proteins play a role in ovarian follicular growth and development, dominant follicle selection, or follicular atresia and development of oocytes; however, the function of the other differentially expressed proteins in reproduction remains ambiguous.

Physiological insight into the high-altitude adaptations in domesticated yaks (Bos grunniens) along the Qinghai-Tibetan Plateau altitudinal gradient

The cold, hypoxic conditions of high-altitude habitats impose severe metabolic demands on domesticated yaks (Bos grunniens). Understanding how yaks cope with the combined effects of hypoxia and aerobic metabolism can provide important insights into the process of adaptive evolution. Here, hematological parameters, blood gases and blood volume, as well as enzyme activity, were determined in yaks from different altitudes. A total of 60 yaks, including 16 Tibet Alpine yaks (approximately 5100m a.s.l.), 23 Gannan yaks (3585m a.s.l.) and 21 Tianzhu white yaks (2960m a.s.l.) in the typically alpine meadows for the altitude of the Tibetan Plateau, were compared. The average red blood cell counts (RBC) value (9.34×1012/L) for the Tibet Alpine yaks was significantly higher than those of Gannan yaks (7.34×1012/L) and Tianzhu white yaks (6.77×1012/L) (P<0.05). Similar levels of significance were observed in the hematocrit (HCT), mean cell volume (MCV) and mean corpuscular hemoglobin concentration (MCHC) concentrations in Tibet Alpine yaks. Increases in hemoglobin (Hb) occurred in the Tibet Alpine yaks, with values of 13.21 and 10.67g/dl for the Gannan yaks and Tianzhu white yaks, respectively, which were lower than that of the Tibet Alpine yaks (P<0.05). Gas-tension and pH changes resulting from chronic hypoxia were evident in the reduced O2 and CO2 tensions in both venous and arterial blood and the slight but significant increase in the blood pH. The blood volume displayed a similar pattern of being greater in the Tibet Alpine yaks than in the Gannan yaks and Tianzhu white yaks. Lactate (LA) and lactate dehydrogenase (LDH) activity positively correlated with altitude (P<0.05). These results are interesting in respect to the low-oxygen environment in which yaks live and are consistent with the higher myoglobin (Mb) concentration in yak cardiac muscle, possibly permitting this type of yak muscle to be switched to aerobic metabolism when needed. These results suggest that Hb levels are not a totally conclusive explanation for the yak adaptation to high altitude, and the physiological adaptation was achieved in yaks perhaps by increases in RBC and blood oxygen affinity and decreases in MCV. In addition, enhanced enzymatic activity plays a key role in added metabolic cost and anaerobic metabolism.

Molecular Cloning, Bioinformatics Analysis and Expression of Insulin-Like Growth Factor 2 from Tianzhu White Yak, Bos grunniens

The IGF family is essential for normal embryonic and postnatal development and plays important roles in the immune system, myogenesis, bone metabolism and other physiological functions, which makes the study of its structure and biological characteristics important. Tianzhu white yak (Bos grunniens) domesticated under alpine hypoxia environments, is well adapted to survive and grow against severe hypoxia and cold temperatures for extended periods. In this study, a full coding sequence of the IGF2 gene of Tianzhu white yak was amplified by reverse transcription PCR and rapid-amplification of cDNA ends (RACE) for the first time. The cDNA sequence revealed an open reading frame of 450 nucleotides, encoding a protein with 179 amino acids. Its expression in different tissues was also studied by Real time PCR. Phylogenetic tree analysis indicated that yak IGF2 was similar to Bos taurus, and 3D structure showed high similarity with the human IGF2. The putative full CDS of yak IGF2 was amplified by PCR in five tissues, and cDNA sequence analysis showed high homology to bovine IGF2. Moreover the super secondary structure prediction showed a similar 3D structure with human IGF2. Its conservation in sequence and structure has facilitated research on IGF2 and its physiological function in yak.

Molecular Cloning and Bioinformatics Analysis of APEX1, a DNA Base Excision Repair Enzyme from the Tianzhu White Yak（Bos grunniens）

The molecular genetics of searching candidate gene on high-attitude adaptability and resistance to cold has become a worldwide hot topic in plateau biology, especial in human and yak. APEX1 as a reference gene, playing a crucial role in Base Excision Repair (BER) enzyme, researches about yak APEX1 can help to understand the adaption of yak in plateau, and then further to increase its economic value. Full length cDNA sequence of apurinic/ apyrimidinicsite endonuclease 1 (APEX1) was cloned from Tianzhu white yak to study the roles of APEX1 and its mechanisms in stress resistance. PCR and RACE techniques were used to obtain the full length of APEX1 cDNA sequence. The result indicated that the full length cDNA of yak APEX1 was 1391 bp (GenBank accession No. KF611690), with an ORF 957 bp encoding 318 amino acids. The amino sequence analysis indicated that APEX1 was highly conserved in most mammals. The predicted molecular weight and pI of yak APEX1 were 35.1 KDa and 7.82, respectively. According to the analysis of APEX1 amino acid in Tianzhu white yak, APEX1 was a kind of hydrophilic, but not a secreted and transmembrane protein. The predicted 3D structure of APEX1 has similar folds and topology with that of human APEX1. The relative expressions of APEX1 in the liver, heart, testis, ovary, lung, brain, muscle, spleen and kidney were detected by quantitive real-time PCR, the result suggested that the highest expression level of yak APEX1 mRNA was in brain, and followed by ovary, spleen and kidney.

A Comparative Study of Tianzhu White Yak's Blood Copper with Yak's in Other Sites of Tibetan Plateau

One hundred and ten individually male yaks which lived in eleven sites around Qinghai Tibetan Altiplano were used to determine the whole blood concentrations of trace elements (Cu, Cr, Mn). Yak were stratified by regions to 11 sites. The eleven areas or treatments is Tibet (including Yadong, Rikeze, Dangxiong, Shannan), Qinghai (including Yushu, Maqin, Dari), Gansu (including Tianzhu and Sunan), Xinjiang (including Heshuo, Yiwu), respectively. The date of experiment showed that the trace elements concentrations of whole blood range were copper 0.585-0.755 mu g/mg, chromium 17.315-20.877 mu/mg and manganese 0.216-0.264 mu/mg, respectively. Results indicate that the copper concentrations in whole blood of white yaks lived in Tanzhu were specific lower than they were on whole blood of yak which lived in other areas else. Analysis of correlation between copper and other trace elements in plasma from yaks also found a significant positive correlations. The correlations between plasma copper, chromium and manganese were r = 0.282 and 0.254 (p < 0.01), respectively.

Genetic polymorphisms of the IGF-II gene intron 8 coding region and its association with growth and carcass traits in yak

Insulin-like growth factor II (IGF-II) plays a key role in mammalian growth and is involved in stimulating fetal cell division, differentiation, and metabolic regulation. IGF-II is considered a candidate gene for genetic markers of growth and carcass traits. Therefore, in this study, the associations of single nucleotide polymorphisms (SNPs) in the IGF-II gene region with growth and carcass characteristics in five yak breeds were investigated. Two SNPs, G(330)C and A(358)G, were identified by sequencing intron 8 of the IGF-II gene in homozygotes. Two alleles, A and B, and three genotypes, AA, AB, and BB, were identified by polymerase chain reaction. Genotypic frequencies of IGF-II allele B were 0.8623, 0.8936, 0.8535, 0.8676, and 0.8300 for Datong yak, Gannan yak, Tianzhu white yak, Qinghai Plateau yak, and Xinjiang yak, respectively. Allele and the genotype of IGF-II were strongly associated with growth and carcass traits. Least square analysis revealed a significant effect (P < 0.01) of genotypes AA and AB compared with genotype BB on live-weight (at 12, 13-24, and 25-36 months of age), average daily weight gain (P < 0.01) and carcass weight (P < 0.05). Animals with genotype AB had a higher mean rib eye area, and a lower mean yield grade. The results indicated that the IGF-II gene acts by a primarily additive biological mechanism by adding weight independently of skeletal growth.

Genetic diversity analysis of DRB3.2 in domestic yak (Bos grunniens) in Qinghai-Tibetan Plateau

DRB3 gene has been extensively evaluated as a candidate marker for association with many bovine disease and immunological traits. A hemi-nested polymerase chain reaction-sequencing method was used to investigate the polymorphisms of DRB3.2 gene from 209 individuals in three different domestic yak ( Bos grunniens ) populations (62 Tianzhu white yaks, 78 Gannan yaks and 69 Datong yaks) from the Qinghai-Tibetan Plateau. Sixty-three polymorphic sites and 143 haplotypes were detected. The percentage of polymorphic sites in Gannan Yak (GNY), Tianzhu white Yak (TWY) and Datong Yak (DTY) were 21.80, 29.95 and 12.95%, while the haplotype diversity were 0.9987, 0.9984 and 0.9855, respectively. At the amino acid level, Glu had the highest content; the percentage was 12.326%, followed by Arg (10.315%), Phe (10.804%), Val (8.346%), Gly (8.315%), Leu (6.606%) and Ala (5.851%), whereas Met and Ile were below than 1%. Only 19 amino acids were found in DTY, Met was lost. Among the synonymous codons, whose third base was G and/or C had a higher usage frequency. Most variability were found in amino acid residues 11, 13, 26, 28, 30, 32, 37, 56, 57, 59, 60, 61, 67, 70, 71, 72, 73 and 74. In GNY, the residues at positions 71, 11 and 72 were highly polymorphic with 8, 7 and 7, at 50, 58, 70, 74 and 78, the residues were selectively polymorphic than other yak populations; the other polymorphic sites were common in the populations. The results of this study indicated that the Chinese domestic yak populations in the Qinghai-Tibetan Plateau have abundant polymorphism in DRB3.2, and the GNY was the highest, followed by TWY and DTY. Key words: Domestic Yak, Hemi-nested PCR, BoLA-DRB3.2, polymorphism.

Conserved Exon 2 but a Highly Polymorphic 5’-UTR of Tyrosinase Gene in Tianzhu White Yak (Bos grunniens)

Conserved Exon 2 but a Highly Polymorphic 5’-UTR of Tyrosinase Gene in Tianzhu White Yak (Bos grunniens)

Polymorphic but highly conserved Bogr‐DRA gene in yak (Bos grunniens)

Samples/PCR conditions: Thirty-nine Gannan yak collected inMaqu county and 60 Tianzhu White yak collected in Tianzhucounty of Gansu Province, China, were used to search for SNPswithin their BoLA-DRA exon 2. Genomic DNAs were extractedfrom peripheral blood using the routine phenol/chloroformprotocol. A pair of primers

A novel single nucleotide polymorphism in exon 7 of LPL gene and its association with carcass traits and visceral fat deposition in yak (Bos grunniens) steers

Lipoprotein lipase (LPL) is considered as a key enzyme in the lipid deposition and metabolism in tissues. It is assumed to be a major candidate gene for genetic markers in lipid deposition. Therefore, the polymorphisms of the LPL gene and associations with carcass traits and viscera fat content were examined in 398 individuals from five yak (Bos grunniens) breeds using PCR-SSCP analysis and DNA sequencing. A novel nucleotide polymorphism (SNP)-C→T (nt19913) was identified located in exon 7 in the coding region of the LPL gene, which replacement was responsible for a Phe-to-Ser substitution at amino acid. Two alleles (A and B) and three genotypes designed as AA, AB and BB were detected in the PCR products. The frequencies of allele A were 0.7928, 0.7421, 0.7357, 0.6900 and 0.7083 for Tianzhu white yak (WY), Gannan yak (GY), Qinghai-Plateau yak (PY), Xinjiang yak (XY) and Datong yak (DY), respectively. The SNP loci was in Hardy-Weinberg equilibrium in five yak populations (P>0.05). Polymorphism of LPL gene was shown to be associated with carcass traits and lipid deposition. Least squares analysis revealed that there was a significant effect on live-weight (LW) (P<0.01), average daily weight gain (ADG) and carcass weight (P<0.05). Individuals with genotype BB had lower mean values than those with genotype AA and AB for loin eye area and viscera fat weight (% of LW) in 25-36 months (P<0.05). The results indicated that LPL gene is a strong candidate gene that affects carcass traits and fat deposition in yak.