A 1.1 Mb duplication CNV on chromosome 17 contributes to skeletal muscle development in Boer goats

The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance.However,the genetic basis of muscle development in the Boer goat remains obscure.In this study,we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development.A total of9 959 autosomal copy number variations(CNVs) were identified through selection signal analysis in 127 goat genomes.Specifically,we confirmed that the highest signal CNV(HSV) was a chromosomal arrangement containing an approximately 1.11 Mb(CHIR17:60062304-61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region(CHIR17:60145940-60151302 bp) with overlapping genes(e.g.,ARHGAP10,NR3C2,EDNRA,PRMT9,and TMEM184C).The homozygous duplicated HSV genotype(+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats.The expression network of three candidate genes(ARHGAP10,NR3C2,and EDNRA)regulating dose transcription was constructed by RNA sequencing.Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells(SMSCs) and their overexpression significantly increased the expression of SAA3.The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes.

Early Growth and Development of Boer Goats from Embryo Transplant

[ Objective] To study the growth-development of Boer goats from embryo transplant. [ Method] With Boer goats from embryo transplant as the tested animals and natural breeding Boer goats born in the same period as CK, the weight of Boer goats at birth and at the age of 1,3 and 6 months as well as the body size at the age of 3 and 6 months were investigated in this study, while their health conditions were also observed and recorded. [ Result] Under the normal feeding conditions, Boer goats from embryo transplant developed well at early stage, and their meat-using body type were also obvious. The average birth weight of bucks was （4.25±0.95） kg, and that of does was （3.74±0.10） kg. The average weight of bucks at the age of 6 months was （31.90 ±0.74） kg and that of was （25.90 ±0.67） kg. The daily gains of bucks and ewes from birth to 6 months of age were 153.64 and 123.11 g respectively, while their body length, body height and chest circumference increased obviously, and there was no significant difference in body weight or body size between them and natural breeding goats. [ Condusioa] The study lays a foundation for further studies on the breedinq and utilization of Boer noats from embryo transplant at early staae.

Identification and Phylogenetic Analysis of an Orf Virus Isolated from an Outbreak in Boer Goat in Shanxi Province

To identify and analyze the Orf virus in Shanxi Province, China, an Orf virus strain was successfully isolated from crust materials of boer goat with clinical sore mouth symptom from a goat farm of Shanxi Province by passaging in lamb testis （LT）. The Orf virus was identified by enzyme linked immunosorbent assay （ELISA） test, recurrent infection test, transmission electron microscopy, and PCR. The nucleotide and amino acid sequences of two genes of the Orf virus were analyzed. The results showed that under the electron microscopy the virus had a presence of typical parapoxvirus virions and there were many eosinophilic intracytoplasmic inclusions observed by hematoxylin-eosin （H＆E） stain. In ELISA test, optical density （OD） readings of the sample showed a positive result, and the rabbits infected with the virus showed a typically Orf virus-infected appearance. All these findings proved that the sample was an Orf virus. The phylogenetic studies of Orf B2L and Orf F1L genes showed that the virus clustered in different branches and were closer to the Orf virus Nantou （DQ904351） and the OV-SA00 isolates （AY386264）. Furthermore, the above results may provide some insight into the genotype of the etiological agent responsible for the Orf outbreak in Shanxi Province, and could also provide a comparative view of the B2L and F1L genes of parapoxvirus.

AFLP and RAPD Analysis of the Boer and Indigenous Breeds of the Goat in Jiangsu

Blood and tissue samples were collected from 105 goats including 60 Boer goats (30 for each sex), 30 Xuhuai goats (15 for each sex) and 15 Haimen goats (7 stud and 8 does). DNA was extracted and DNA pools were constructed on the basis of goat breeds. In 36 selective primer combinations, 29 combinations amplified totally 3 253 markers including 92 polymorphic markers by amplified fragment length polymorphism (AFLP). On average, 3.17 polymorphic markers were amplified per combination, with a polymorphic frequency of 2. 8%. The primer combinations amplifying more polymorphic markers (showed in brackets) were involved in E00+ACG/M00+CAA (13), E00+ACG/M00+CAG (10), E00+AAC/M00+CAC (8) and E00+A AC/M00+ACT (7). A total of 183 markers including 60 polymorphic markers were amplified by RAPD from the pooled DNA of three breeds using 22 primers with strong polymorphism and high reproduc-ibility selected from 93 RAPD primers. On average, 2. 73 polymorphic markers were amplified per primer, with a polymorphic frequency of 32.8%. The results of AFLP and RAPD coincidently suggested that the genetic distance is the closest between Xuhuai and Haimen goat, next between Xuhuai and Boer goat, and the farthest between Haimen and Boer goat. According to the UPGMA method, Haimen and Xuhuai goats can be gathered together as a cluster, then Boer goat. Both methods can be used to implicate the genetic difference of these three breeds, in particular AFLP has more polymorphic markers.

Genetic Polymorphism of Ten Microsatellites in Two Goat Breeds and Its Relationship with Heterosis

[Objective] This study aimed to investigate the genetic diversity of Macheng black goat and its correlation with heterosis.[Method] Ten microsatellite markers were selected for polymorphism investigation and statistical analysis of Boer goat and Macheng black goat populations.[Result] The results showed that totally 175 alleles were found in 10 microsatellite loci; to be specific,the maximum number of detected alleles was 23,and the minimum number was 10; the effective number of alleles （Ne） was 6.4-18.1,with absolute difference value of 1.6-8.1 from the observed number of alleles.The highest gene frequency was 0.239 1 and the lowest was 0.002 7.The polymorphic information contents of all the ten microsatellite markers were above 0.95.The observed heterozygosity （Ho） ranged from 0.616 7 to 0.984 4 and the expected heterozygosity （He） ranged from 0.844 1 to 0.944 6.The average expected heterozygosity of Boer goat and Macheng black goat was respectively 0.894 0 and 0.906 7.Various body weight and body size indices of Boer goatxMacheng black goat hybrids were improved in varying degrees compared with Macheng black goat （with an increase range of 0.32％-30.06％）.The average heterosis rates of body height and chest girth were relatively high,while average heterosis rate of body weight was relatively low.[Conclusion] The genetic distance between Boer goat and Macheng black goat was 0.379 5,which is consistent with the geographical distribution of Boer goat and Macheng black goat populations and is fully relevant to the heterosis of Boer goat × Macheng black goat hybrids,indicating that investigating polymorphism via microsatellite loci is one of the feasible means to predict and analyze heterosis between varieties.