Occurrence of repeat breeding in crossbred dairy cattle
S. Aruna, A.C.P. Abdul, K. Promod, B.K. Lekshmi and M. Ashokkumar
The present research work was undertaken to evaluate the occurrence of repeat breeding (RB) among crossbred dairy cattle for three years from January 2017 to December 2019. Crossbred cows having apparently normal genitalia and showing regular oestrous cycle but failing to conceive even after three consecutive inseminations were selected as RB cows based on data collected from breeding registers. The occurrence of RB in the year 2017, 2018 and 2019 were 29.20, 24.12 and 19.52 per cent, respectively with an overall occurrence of 23.60 per cent. Detailed clinico-gynaecological and ultrasonographic examinations of 41 RB cows were carried out for the identification of various etiological factors during the study period (September 2019 to August 2020). Samples for endometrial cytology were collected during oestrus by cytobrush technique to rule out cytological endometritis (sub clinical endometritis). The occurrence of various identified causes of RB were cytological endometritis (17.07 %), fibrosis of cervix (7.31 %), endometritis (7.31 %), follicular cyst (4.88 %), kinked cervix (2.44 %), uterine unicornis (2.44 %) and other reasons (58.54 %). Repeat breeding is a major cause of infertility in crossbred dairy cattle and early diagnosis is essential for the effective management and to enhance production.
Keywords: Cytological endometritis, occurrence, repeat breeding