Seasonal Variations of Body Condition Score and its Effect on Reproductive Performance of Dairy Cattle

Objectives of the study were to investigate and assess body condition score (BCS) of dairy cattle seasonally to find out its efficiency as management tool, throughout manage health and nutrition, improve reproductive performance, fertility and productivity of dairy cattle. A total of 30 Holstein Cows (multiparous and nulliparous) in the experimental farm of Hiroshima University were included in the experiment. A five-point scale body condition scoring system was used to assess BCS of individual cows monthly. Visual observation, special calendar for dairy cattle management, heating detection patches, automatic heating detection system and hormone treatment were used for heating detection of dairy cattle. Artificial insemination (AI) was done by experienced and skillful technicians following to successful heating detection. Body Condition of every cow that received AI was evaluated and recorded on the day of breeding separately. Rectal palpation and ultrasound system were used to determine and diagnose the condition of success or failure of AI. Dairy cattle with mean of 3.00±0.13 BCS during fall season showed higher reproductive performance (72.723%). During winter season mean BCS of dairy cows was almost the same as fall season (3.04±0.11) but positive response to AI and pregnancy was lower (41.10076) than fall season. In summer season cows with BCS 3.50 responded positively to AI and become pregnant while cows with mean of 3.31±0.10 BCS failed to become pregnant. statistical analysis of BCS between four seasons of the year showed that increase/decrease of BCS even less than 0.25 points can change efficiency of body condition scoring as management tool. Therefore; efficiency of body condition score as a management tool for dairy farms can change seasonally. Maintenance of dairy cattle with BCS 3.0 during fall and winter following to synchronization and timed artificial insemination (TAI) would increase reproductive performance, fertility and productivity of dairi