Relationship between Lithuanian White and Black cows body condition and reproduction

摘要

Cow reproduction is considered to be one of the most subtle physiological functions, which depends on the health of the whole organism. It is the most important indicator, according to which cow storage strategy is organized. Fertility is another no less important factor influencing the profitability of dairy herds (25). In recent years a progressive worsening of fertility indices in dairy cow herds has been observed (8). Problematically inseminated cows, many rebreedings, and long service period cause great disadvantages for cattle breeders. Due to these problems the number of calves decreases, ef-fectivity of forage use is reduced, productivity of the farm declines. Sterility of cows is determined by the poor management of reproduction, incorrectfeeding of cows during early lactation and often by bad cattle holding condition (17, 18). Results of poor management of reproduction are mostly observed after half a year or even later and correction of these mistakes also takes a good deal of time. Therefore, cattle breeders are looking for new methods which could help solve or avoid reproduction problems. One of the best methods is assuring recommended body conditions for cows during all production phases, especially at calving (19,20).