Tuyển tập các báo cáo nghiên cứu về bệnh thú y được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành thú y đề tài: Effects of Complex Vertebral Malformation on Fertility in Swedish Holstein Cattle. | Acta vet. scand. 2004 45 161-165. Effects of Complex Vertebral Malformation on Fertility in Swedish Holstein Cattle By Britt Berglund1 Anna Persson1 and Hans Stảlhammar2 department of Animal Breeding and Genetics Centre for Reproductive Biology in Uppsala Swedish University of Agricultural Sciences Uppsala and 2Svensk Avel Skara Sweden. Berglund B Persson A Stâlhammar H Effects of complex vertebral malformation on fertility in Swedish Holstein cattle. Acta vet. scand. 2004 45 161-165. - Complex vertebral malformation CVM is an autosomal recessive inherited defect in the Holstein breed. It causes intra-uterine mortality through the entire gestation period leading to repeat breeding and involuntary culling of cows and thereby economic losses. The defect was first reported in Denmark in 1999 and a direct DNA test for the defect has been available since February 2001. The aim of this study was to investigate if Holstein bulls heterozygous for the CVM gene had reduced reproductive performance measured as non-return rate NRR and in a daughter fertility index. All genotyped Swedish Holstein bulls born between 1995 and 1999 were included. Altogether 228 bulls were analysed of which 53 bulls . 23 were confirmed CVM carriers. A statistically significant difference between carriers and non-carriers in the relative breeding value for NRR was observed for 168 days NRR vs. p . There was no difference for 28 days NRR whereas the difference approached significance for 56 days NRR. No significant effect of the paternal CVM genotype on the daughter fertility index was shown probably due to the complexity of traits this index is composed of. In conclusion the study showed that carriers of the CVM defect have an inferior NRR compared with non-carriers. CVM congenital defect non-return rate dairy cattle. Introduction Complex Vertebral Malformation CVM is an autosomal recessive inherited defect in the Holstein breed first described in Denmark in 1999 by .
