An Interdisciplinary Review of Body Condition Scoring for Dairy Cattle

In this review, methods for assessing energy reserves, the role of assigning BCS in dairy management, and the impact of varying BCS on animal productivity, health, and reproduction are explored from a whole-system viewpoint. The usefulness, validity, and precision of BCS for assessing body energy reserves are well documented. Generally, BCS decrease in early lactation as cows partition energy from body reserves to support milk production, and they then begin to increase throughout the remainder of lactation. Excessive loss of energy reserves during early lactation, generally associated with cows of higher BCS at calving, often results in impaired health and reproductive performance. Among diseases, the most consistent relationship has been an increased incidence of ketosis for cows with higher BCS at calving. Although published results have varied, either high or low BCS has also been related to greater incidences of metritis, retained placenta, milk fever, lameness, cystic ovaries, dystocia, displaced abomasum, and mastitis. Losses in BCS or the actual BCS are associated with various fertility measures including days to first ovulation, days to first estrus, days to first service, first service conception rate, number of services, calving interval, and embryonic losses. Patterns of BCS change within lactation are under genetic control indicating potential for inclusion of BCS in genetic evaluations. Concerns about subjectivity and the time required for scoring have limited the use of BCS in daily management. An automated BCS might provide a more objective, less time-consuming means of estimating energy reserves in dairy cattle.