The aim of this study was to compare the prevalence of factor XI deficiency (FXID) carriers and potential financial losses depending on ‘extended calving interval’ and ‘extra service’ in normally fertile and repeat breeder cows in Turkey. For this purpose, a total of 161 Holstein cows were genotyped for the FXI gene mutation originating from various herds located in the Middle Anatolian region of Turkey. In the study, animals were divided into two groups – normally fertile (n = 118) and repeat breeding (n = 43) cows. In each group, one FXID carrier animal was identified and the prevalence of the FXID carrier was found to be 0.85 and 2.33% in normally fertile and repeat breeder cows, respectively. In a financial analysis, it was determined that extended calving interval in a normally fertile cow caused $246 losses and $546 losses in a repeat breeder cow. Additionally, financial losses due to extra service per conception were calculated as $12 and $36 per cow in normally fertile and repeat breeder cows, respectively. In normally fertile and repeat breeder cows, the sum of losses due to extended calving interval and extra service was calculated as $258 (246 + 12) and $582 (546 + 36). This study found that a repeat breeder cow causes an extra $324 ($582 – $258) financial loss compared with a normally fertile cow. Consequently, unlike other genetic disorders like BLAD and DUMPS, which do not decrease the performance of carrier animals, the mutant FXI allele could lead to repeat breeder syndrome in FXID carrier cows and cause important financial losses in dairy farms.
Screening for bovine leukocyte adhesion deficiency, deficiency of uridine monophosphate synthase, complex vertebral malformation, bovine citrullinaemia, and factor XI deficiency in Holstein cows reared in Turkey
