How fat is my cow?
Body condition scoring (BCS) is an assessment of a cow’s energy reserves. It provides a visual assessment of her “fatness” from which she can be categorised into a scale of 1-10 with 1 being emaciated and 10 being obese.
In research conducted in New Zealand and internationally it has been found that the body condition score of a dairy cow has significant effects on dry matter intake, milk production, reproduction and cow health and welfare. This research has led to condition score targets at key lactation times to help improve and enhance production systems.
One of the BCS targets is to have mature cows calve at a condition score of 5 with no more than 15% of the herd less than a condition score of 5 or greater than a 5.5. First and second calvers need to be 5.5 at calving ideally reaching this within 60 days of calving. To meet these calving targets, regular body condition scoring needs to be carried out at key times. This allows you to set up feed management plans for the herd to help limit BCS losses, increase BCS and assess if those plans worked.
One of the most important times to BCS is now (mid-February to mid-March). This allows assessment of your cow’s condition, so you can decide on strategies to help manage and plan to ensure they reach target BCSs at calving. This includes approaches like the early dry-off of some animals, especially if they have been pregnancy tested as early calvers. Changing to once a day milking, running separate herds and preferential feeding with special attention paid to first calvers as they are found to struggle the most to gain BCS. The below table from DairyNZ is a helpful resource in how much dry off time an animal needs for her current BCS to achieve target BCS at calving.
Body condition scoring is assessed by using the DairyNZ BCS method. This method is regarded as the standard and is recommended by the Ministry of Primary Industries and is part of the Dairy Cattle code of Welfare 2018. The method involves assessing the fat reserves at eight different points across the cow’s frame. The eight points consist of the backbone, long ribs, short ribs, hip bones, rump, pin bones, tailhead and thigh. Cows should always be condition scored from the right-hand side and the rear of the cow as rumen fill can obscure her true condition score. To ensure consistent results it is important to calibrate your eye by condition scoring 15 cows “hands on” at the dairy before heading off to the herd. Once confident and calibrated, condition score 70 randomly selected animals (if herd size is greater than 100 animals) to allow for a true representation of the average and range of the herds BCS. While not ideal to BCS in the shed while cows are being milked due to not being able to see and assess all eight body parts with the use of a well placed and trained assessor it can be managed.
Now is the time to act as failure to achieve BCS targets is often a lack of time rather than a lack of feeding.
If you would like an independent assessment of the condition score of your herd or assist you or your staff in learning this valuable skill, please do not hesitate to contact your local clinic.