Wpływ systemu utrzymania i intensywności zywienia na częstość występowania schorzeń wymienia u bydła fryzyjskiego

For five years there was observed the occurrence of udder diseases in 656 cows representing 10 types of Fresians held in two cowsheds, where the animals were on the chains, and in two cowsheds with free cow stalls without fedding; the intensiveness of feeding was also different. Of the factors studied a significant influence on the udder diseases had only board system. In cowsheds with tied animals they got ill 3 times more often than those in free stalls cowsheds. Neither the genotype of cows nor interactions between the system of feeding and a genotype influenced markedly the diseases of udders. Though not statistically significant effect of the genotype on the occurrence of mastitis was stated some differences among the types were observed. Twice less cows with the genes of Israel type got ill than those of British type.