Methods and Technical Key Points for Body Condition Control in Dairy Cows

The main purpose of raising dairy cows is milk production. An appropriate body condition helps dairy cows maximize their production capacity, so the body condition requirements for dairy cows differ across lactation stages. Body condition is generally required to be moderate. Being too thin indicates that the cow is malnourished; being too fat is also not good, as it causes excess nutrition, feed waste, and can easily lead to difficult conception, postpartum obesity syndrome, fatty liver and other diseases, and milk yield will not increase either.

Regularly assessing the body condition of the herd and promptly adjusting the feeding plan and ration formula according to body condition can raise production levels and reduce feeding costs. Body condition scoring for dairy cows uses a 5-point system: a low score means thin condition, a high score means fat condition, and the suitable body condition is between 2.5 and 3.5 points. The optimal body condition scores for dairy cows at different physiological and lactation stages are as follows: 3.5 points at calving; during the first 3 months of lactation, the cow is in a negative nutritional balance and body weight gradually declines. For every 1 kg drop in the cow's body weight, milk yield increases by 7.5 kg (at 3.5% milk fat). Generally, at the peak of lactation the score is 2.0-2.5 points; entering late lactation, only then is there surplus energy stored and body weight rebounds, and by the seventh lactation month the body condition is 2.5-3.0 points; at dry-off it is 3.0 points.

The relationship between body condition and body weight can be estimated by the following formula: heart girth (m) x heart girth (m) x body oblique length (m) x 90 = body weight at moderate body condition (3 points). For cows of the same body type, for every 60 kg more body weight, the body condition is 1 point higher; for every 60 kg less body weight, the body condition is 1 point lower. For example: for a cow with a standard body type of 2.02 m heart girth and 1.63 m body oblique length, the body weight at 3.0 points body condition is 600 kg (2.02 x 2.02 x 1.63 x 90). If the body weight is 660 kg, then the body condition is 4.0; if the body weight is 540 kg, then the body condition is 2.0, and so on.