Optimization of rearing dairy breed calves according to organic principles / Optymalizacja odchowu cieląt ras mlecznych według wymogów ekologicznych

The aim of the study was to determine the degree to which different whole milk feeding systems according to ecological standards affect the results of rearing, some blood biochemical and haematological parameters, and health status of Polish Holstein-Friesian calves. The experiment was conducted from birth to 150 days of age with 32 calves (16 heifer and 16 bull calves), assigned to four analogous groups (8 animals: 4 ♀ and 4 ♂ per group). In group I, calves suckled colostrum (ad

libitum) and mother’s milk from 5 to 90 days of age (twice daily for 30 minutes); in group II, they suckled colostrum (ad libitum), mother’s milk from 5 to 42 days of age (twice daily for 30 minutes), and received milk from nipple buckets (6 l twice daily) from 43 to 90 days of age; in groups III and IV calves received from nipple buckets a limited amount of colostrum (4.5-6 l/day) and milk (on average 5.82 and 4.82 l/day, respectively). Feeding limited whole milk from nipple buckets to the calves did not cause significant differences in haematological blood indices, serum concentrations of glucose and IgG, and health status of calves compared to those suckling their mothers. Calves which remained with their mothers during colostrum feeding were characterized by a significantly lower concentration of serum cortisol at 2 days of age compared to calves that received colostrum from nipple buckets. Compared to the calves suckling their mothers (group I), the use of economical milk feeding system (III and IV groups) reduced rearing costs and increased the amount of milk intended for sale by 700-760 l/cow.