Analysis on Polymorphisms of GHR Gene in Improved Hybrid Yellow Cattle Groups from Liupan Mountain Area in Ningxia

[Objective] The paper aimed to analyze the polymorphism of the growth hormone receptor （GHR） in improved hybrid yellow cattle group from Liupan Mountain area in Ningxia Autonomous Region,so as to provide technological basis for hybrid improvement. [Method] Polymerase chain reaction-restriction fragment length polymorphisms （PCR-RFLP） technology was carried out to examine polymorphisms of GHR gene of 70 individuals. [Result] The target fragment of 338 bp was amplified. The PCR product digested by restriction enzyme Alu I showed polymorphisms. The frequencies of the two genotypes （AA,BB） were 75.71% （53 individuals） and 24.29% （17 individuals）,respectively. [Conclusion] Two genotypes of GHR gene were detected in improved hybrid yellow cattle groups from Liupan Mountain area in Ningxia.

Effects of different dietary energy and protein levels and sex on growth performance,carcass characteristics and meat quality of F1 Angus x Chinese Xiangxi yellow cattle

Background：The experiment evaluated the effect of nutrition levels and sex on the growth performance,carcass characteristics and meat quality of F1 Angus × Chinese Xiangxi yellow cattle.Methods：During the background period of 184 d,23 steers and 24 heifers were fed the same ration,then put into a2×2×2 factorial arrangement under two levels of- dietary energy（TON：70/80%DM）,protein（CP：11.9/14.3%DM）and sex（S：male/female） during the finishing phase of 146 d.The treatments were-（1） high energy/low protein（HELP）,（2） high energy/high protein（HEHP）,（3） low energy/low protein（LELP） and（4） low energy/high protein（LEHP）.Each treatment used 6 steers and 6 heifers,except for HELP- 5 steers and 6 heifers.Results：Growth rate and final carcass weight were unaffected by dietary energy and protein levels or by sex.Compared with the LE diet group,the HE group had significantly lower dry matter intake（DMI,6.76 vs.7.48 kg DM/d）,greater chest girth increments（46.1 vs.36.8 cm）,higher carcass fat（19.9 vs.16.3%） and intramuscular fat content（29.9 vs.22.8%DM）.The HE group also had improved yields of top and medium top grade commercial meat cuts（39.9 vs.36.5%）.The dressing percentage was higher for the HP group than the LP group（53.4 vs.54.9%）.Steers had a greater length increment（9.0 vs.8.3 cm）,but lower carcass fat content（16.8 vs.19.4%） than heifers.The meat quality traits（shear force value,drip loss,cooking loss and water holding capacity） were not affected by treatments or sex,averaging 3.14 kg,2.5,31.5 and 52.9%,respectively.The nutritive profiles（both fatty and amino acid composition） were not influenced by the energy or protein levels or by sex.Conclusions：The dietary energy and protein levels and sex significantly influenced the carcass characteristics and chemical composition of meat but not thegrowth performance,meat quality traits and nutritive profiles.

Genetic background analysis and breed evaluation of Yiling yellow cattle

Traditionally, Chinese indigenous cattle is geographically widespread. The present study analyzed based on genome-wide variants to evaluate the genetic background among 157 individuals from four representative indigenous cattle breeds of Hubei Province of China： Yiling yellow cattle （YL）, Bashan cattle （BS）, Wuling cattle （WL）, Zaobei cattle （ZB）, and 21 indi- viduals of Qinchuan cattle （QC） from the nearby Shanxi Province of China. Linkage disequilibrium （LD） analysis showed the LD of YL was the lowest （~=0.32） when the distance between markers was approximately 2 kb. Principle component analysis （PCA）, and neighbor-joining （NJ）-tree revealed a separation of Yiling yellow cattle from other geographic nearby local cattle breeds. In PCA plot, the YL and QC groups were segregated as expected; moreover, YL individuals clustered together more obviously. In the N J-tree, the YL group formed an independent branch and BS, WL, ZB groups were mixed. We then used the FST statistic approach to reveal long-term selection sweep of YL and other 4 cattle breeds. According to the selective sweep, we identified the unique pathways of YL, associated with production traits. Based on the results, it can be proposed that YL has its unique genetic characteristics of excellence resource, and it is an indispensable cattle breed in China.

Isolation and Culture of Fetal Fibroblasts of Tibetan Yellow Cattle

[ Objective] To isolate fetal fibroblasts from Tibetan yellow cattle and thus to provide the ideal biological material for cloning and cellular biology of animals inhabiting in the Tibet Plateau. [ Method] The fibroblast cells were isolated from tissues of Tibetan yellow fetus by explant culture method. The subculture, morphology and dynamics were observed. [ Result] The fetal fibroblasts of Tibetan yellow cattle had typical morphology of fibroblast calls. The isolated cells had three growth stages including retention period （0 -2 d）, logarithmic phase （2 -7 d） and platform phase （7 -8 d）. Its doubling time was 60 h. [ Conclusion] Fetal fibroblasts of Tibetan yellow cattle have been successfully cultured.

Improvement Effects of Guizhou Local Yellow Cattle Crossbred with Fleckvieh

[Objective] The aim was to discuss the improvement effect of Guizhou local yellow cattle crossbred with Fleckvieh. [Method] With Fleckvieh as male parent, they were crossbred with Guizhou local yellow cattle （ ♀ ）, and hybridized cattle of Simmental × local yellow cattle （ ♀ ） to determine production performance, slaughter performance and lactation performance of their offspring. And they were compared with Guizhou local yellow cattle. [ Result ] The growth, slaughter and lactation performance of offspring of F1 Fleckvieh （ ♂ ） × Simmental （ ♂ ） × local yellow cattle （ Q ） proved optimal, followed by offspring of F1 Fleckvieh （ ♂ ） × local yellow cattle （ ♀） and offspring of Guizhou local yellow cattle. [ Conclusion] Offspring of improved local yellow cattle crossbred with Fleckvieh （ ♂ ） and hybridized cattle of Fleckvieh × Simmental × local yellow cattle enjoy significant heterosis and the economic benefits of cattle farming could be significantly enhanced.

Polymorphism of POMC Gene in Guizhou Yellow Cattle

[ Objective ] The paper was to explore the effect of pro-epiomelanocortin （POMC） on feeding behavior and energy homeostasis of animals. [ Method ] Using DNA sequencing technology, polymorphisms of POMC gene in 92 individuals of Guizhou yellow cattle were studied. [ Result ] Five mutation sites, 138 C 〉 T, 430 C 〉 T, 644 C 〉 T, 668C 〉 T, 693A 〉 G, were found in the 870 bp amplification product. Polymorphism results showed that except the mutation site 430 C 〉 T that was deviated from the Hardy-Weinberg equilibrium （HWE） state （ P 〈 0.05 ）, the rest mutation sites were at the HWE state （ P 〉 0. 05 ） ; the peptide infor- mation content （PIC） of five mutation sites were moderate polymorphism. [ Conclusion] The POMC gene of Guizhon Yellow Cattle was abundant in genetic diversity, with great selection potential, which could be used as a potential genetic marker of cattle growth traits.

Protection and Utilization of Yellow Cattle Breed Resources in China

Based on the general situation and genetic diversity of yellow cattle breed resources in China,this paper discusses the protection,development and utilization of Chinese yellow cattle breed resources,in order to provide reference basis for the development,utilization and sustainable development of local yellow cattle breeds in China.

Anaerobic Fungal Diversity in the Rumen of Gayals (Bos frontalis) in Yunnan Province, China

To investigate the anaerobic fungal diversity in the rumen of gayals(Bos frontalis), Yunnan yellow cattle, yaks, and Tibetan yellow cattle, the ITS region of ruminal anaerobic fungi was sequenced. The anaerobic fungi found in four types of cattle could be divided into 16 groups(Neocallimastix, Anaeromyces, Orpinomyces, Caecomyces, Cyllamyces and unknown groups 1-11). There were 10 anaerobic fungal groups in the rumen of gayals, with three belonging to known genera(Orpinomyces, Neocallimastix, and Caecomyces), which accounted for 2.8% of sequences of gayals. There were fewer known anaerobic fungi in gayals than in Yunnan yellow cattle(Orpinomyces), yaks(Anaeromyces, Orpinomyces, and Cyllamyces) and Tibetan yellow cattle(Anaeromyces, Orpinomyces, Caecomyces, and Cyllamyces), accounting for 30.7%, 93.9%, and 35% of each of the relevant cattle species. The other seven unknown groups(NG1, NG4, NG6, NG7, NG9, NG10, and NG11) accounted for 91.6% of sequences from gayals, which was higher than Yunnan yellow cattle [69.3%(NG2, NG8 and NG9)], Tibetan yellow cattle [35%(NG4, NG5 and NG9)], and yaks [6.1%(NG3)]. Furthermore, NG1, NG6, NG7, NG10, and NG11 were only found in gayals,whereas NG3 and NG5 were found only in Tibetan yellow cattle and yak, respectively. Piromyces was not found in any of the four types of cattle. The anaerobic fungi abundance in the rumen of gayals was significantly higher than that of the other three types of cattle. The ruminal anaerobic fungi of gayals might have an important role in cellulose degradation, resulting in the ability of this species to successfully graze coarser fodder.

Close Association between 4685 Loci on CAPN1 Gene and Meat Tenderness

[Objective] The paper was to explore the impact of 4685 loci on CAPN1 gene of Yanbian yellow cattle and red steppe cattle on meat tenderness. [Method] The 4685 loci in 14th intron region of CAPN1 gene of Yanbian yellow cattle and red steppe cattle was conducted analysis of gene polymorphism and meat tenderness by PCR-RFLP technology, and the effect of the loci on Jilin local cattle breeds was verified. [Result] The loci had close relationship with related detection indices of meat tenderness （cooking loss, muscle fibre diameter, shear force and drip loss）, and the existence of T allele could significantly increase the tenderness level of in- dividuals, but the loci was not associated to pH value. 4685 loci was not associated to carcass traits （carcass weight, net meat weight and carcass yield ratio）, which only had certain correlation with eye muscle area. [Conclusion] The 4685 loci on CAPN1 gene of Yanbian yellow cattle and red steppe cattle had close association with meat tenderness.