BCS Targets: Why Body Condition Score Matters at Calving
Body Condition Score (BCS) is a critical element in managing the health and reproduction of the dairy herd.
At last month’s Beef + Lamb NZ Genetics sheep breeder forum in Napier, SIL advisor Sharon McIntyre updated ram breeders on new breeding value traits now in the pipeline, including one dedicated to BCS.
BCS is becoming an increasingly popular management tool, because of the positive effect it has on so many key outcomes.
Studies show that a ewe’s body condition directly affects scanning percentage, lamb birthweight and survival, mothering ability, colostrum production and milking ability, lamb growth rates and weaning weights.
Until now, SIL has estimated feed costs for adult ewes on the basis of genetic merit for adult weight. Adding in BCS will improve this estimate of what a ewe will eat.
Over the past five years, about 50 SIL flocks have been submitting BCS data, some as a by-product of their involvement in an Ovita project looking at ewe efficiency. This data has allowed SIL to investigate the workability of a condition score breeding value.
McIntyre says the breeding value is being developed in direct response to breeder feedback that ewe weight does not fully describe all aspects of ewe size.
“Adult size describes one, but not all, aspects of a ewe that impact her production. BCS is a way of getting more information about adult size and performance. It’s a quick, easy and low-cost tool.”
While scores can be recorded at any of four key management times – mating, scanning, lambing and weaning – analysis shows there is a strong correlation between those scores. That means a particular ewe that has an above average BCS at one point in the year is likely to record an above average score at other times. This means breeders need only submit one BCS annually, ideally at mating time and alongside the ewe’s liveweight.
