Effect of the Degree of Udder Contamination in Dairy Cows on the Somatic Cell Count in Milk

ABSTRACT The study includes a total of 310 Black-and-white cows from 9 herds throughout the period from November 2010 till January 2011. The farms used two rearing technologies (free and tied) and were of different capacity. To assess the degree of udder contamination a 4-grade system has been used. The rearing technology and the farm capacity had a reliable effect on somatic cells count (SCC) in milk. In tied rearing higher SCC have been recorded than in free rearing, a lesser relative share of cows with clean udders (hygiene score -1) and a greater one of cows with contaminated udders (hygiene score 3 and 4). The greatest was the relative share of cows with contaminated udders (hygiene score 3 and 4) and the least clean were the cows in farms with tied rearing and capacity from 50 The study includes a total o f 310 Black-and-white cows from 9 herds throughout the period from November 2010 t i l l January 2011. The farms used two rearing technologies (free and tied) and were o f different capacity. To assess the degree o f udder contamination a 4-grade system has been used. The rearing technology and the farm capacity had a reliable effect on somatic cells count (SCC) i n milk. I n tied rearing higher SCC have been recorded than i n free rearing, a lesser relative share o f cows w i t h clean udders (hygiene score -1) and a greater one o f cows w i t h contaminated udders (hygiene score 3 and 4). The greatest was the relative share o f cows w i t h contaminated udders (hygiene score 3 and 4) and the least clean were the cows i n farms w i t h tied rearing and capacity from 50 to 100 cows. Cows w i t h score 1 (clean udder) had the smallest somatic cell count - 172.4x103/ml, which was related to l o w risk o f mastitis diseases. The ones w i t h score 3 and 4 had somatic cell count over 400x103/ml. The availability o f more than 20% o f cows w i t h udder hygiene score 3 and 4 was an indicator for increased risk o f mastitis i n the herd and obtaining l o w quality milk. Somatic cell count i n m i l k depended largely on the maintenance o f bedding and the farm hygiene rather than the farm capacity and the rearing technology