Possible physiological and environmental factors affecting milk production and udder health of dairy cows: A review

The milk production efficiency is affected by many factors, where the quantity and quality are the most important. An important role in the overall milk production economy is not only the current purchase price and the associated costs. The costs of rearing heifers and pregnant animals in relation to future milk production and udder health are very important too. During the rearing of the calf heifers and during the drying off period of the pregnant animals, many factors directly influence the effectiveness of milk production and udder health. Among them, the breeding environment (temperature, ventilation, nutrition etc.), the physiological state (stage and order of lactation, growth intensity of heifers early after birth, duration of drying, the age at first conception or season of calving etc.) and the udder health (the level of somatic cell count at time of dry off and calving) are discussed in the paper.