Department of Animal Nutrition and Dietetics University of Agriculture in Cracow, Poland
Rearing healthy and well growing calves is one of the greatest challenges for modern dairy and meat producers. This, apparently short and lasting just 2 to 3 months period of cow’s life is crucial for farmers’ income. First weeks of life are a time of intensive development of a young organism, particularly its organs crucial for future milk yield and growth of muscle tissue, such as gastrointestinal tract, liver or mammary gland. What has to be emphasized is that any disturbance in the growth of an organism at this early stage of life ( caused by f.ex. diarrhea) cannot be compensated at a later stage. As a result, it inevitably leads to less effective production results from the problem animals as well as their shorter lifespan. Ultimately, poor rearing performance of calves is the reason for substantial financial loss of a farm.
It is estimated that every sickness of a calf within the first weeks of life may reduce milk yield of a future cow from 200 to as many as 1000 liters in each lactation. On the other hand, each increase of body mass during this critical period of life by 1 gram/day translates into a higher milk yield by as many as 4 liters per each day of lactation. Cited values allow to picture the correlation between the first weeks of the animals’ lives and their later productivity.