Factors predisposing to bovine ovarian cystic disease and its effect on reproductive efficiency

Abstract

Ovarian cysts are common anomalies in dairy cattle. They are characterized by presenting with anestrus, irregular estrus, increased reproductive intervals, and infertility. Their origin is still unknown, thus it is important to study their pathogenesis and possible relation to certain factors predisposing to their onset. The objective of this study was to determine by ultrasound the prevalence and types of ovarian cysts. 93 cows belonging to 23 farms in the Hoya de Loja were studied. Cystic formations were identified and classified according to ultrasound profile during 24 days, with 6 scans every 4 days. The age of the animals varied from 2 to 12 years, with body condition > 2. For data analysis, PROC REG was used in the SPSS Statistics 21 statistical program. An increase of 256.4 open days was evidenced in cows with ovarian cysts, versus 114.8 open days in healthy control animals. The prevalence of ovarian cysts was 32%, distributed in follicular cysts (21%) and luteal cysts (11%). In addition, there was a correlation between the presence of cysts and body condition ≤ 3 (23%), presence of metritis (9%), and the use of hormonal products (10%). Ovarian cysts were clinically manifested through symptoms of anestrus in cows with luteal cysts (90%) and the presence of irregular estrus in cows with follicular cysts (40%). In conclusion, ovarian cysts are a direct cause of increased periods of delivery-estrus and delivery-conception, as well as increased intervals between deliveries in postpartum dairy cows.