Wnt7a Mutations in Crossbred Dairy Cows with Kinked Cervix Leading to Infertility

Abstract

The study was conducted on genitalia collected from 100 dairy cows / heifers from the Meat Technology Unit, Mannuthy. The study group included six animals culled on account of factors other than infertility with normal reproductive system (control group) and the remaining animals with a known history of infertility brought from University and Government Undertaking farms. The most common anatomical defect noticed was kinked cervix, which constituted seven per cent of the study sample. Morphology of various parts of the genitalia was noted. Single nucleotide polymorphisms identified in the wnt7a gene were confirmed using polymerase chain reaction and the amplicons were sequenced. The cervix was seen as hard, twisted and bent in the form of an Sshaped structure. The cervical rings were thicker and harder. The opening of each cervical ring showed a misalignment instead of the linear arrangement. The sequence analysis of 272 bp amplicon of wnt7a gene revealed SNPs at positions 89 (A’!G transition) and 119 (A’!G transition). Structural anomalies such as kinked cervix might reduce reproductive effectiveness of the animal, resulting in economic loss to the farmers. Early detection of these anatomical abnormalities in dairy cattle aids in the elimination of the route cause through culling of such animals.