Anotace:
This review aims to highlight the importance of genetic evaluation of health traits. In the past, cattle breeding primarily focused on milk production traits, but nowadays, there is a shift towards considering health traits and longevity. Cows are mainly affected by four diseases: mastitis, claw diseases, metabolic diseases, and reproductive diseases. These ailments negatively impact milk production, impair reproduction, and incur high treatment costs. In 2012, the ICAR implemented guidelines for the genetic improvement of health traits, establishing a system for recording diseases and their key indicators. This system includes a comprehensive key (>900 diagnoses), a reduced key (60 to 100 diagnoses), and a simple key (10 diagnoses). Genetic evaluation of health traits started in the mid-70s in Nordic countries. Previously, Czechoslovakia had a system for evaluating and classifying the overall health of breeding cows and bulls. In Slovakia, genetic evaluations for milk production traits, somatic cell score, calving ease, and longevity are performed. However, these traits are not included in the selection index along with health traits, for which genetic evaluations are not made. Two selection indexes are currently used: the Slovak Holstein Index, which takes into account milk production traits and type traits at 60% and 40% respectively, and the Slovak Production Index, which takes into account milk production in kilograms, fat production in kilograms, and protein production in kilograms.