Abstract
In the last few years there has been increasing emphasis on reducing milk somatic cell count to improve the milk quality in dairy ruminants. Genetic parameters for somatic cell count (SCC), LOGSCC and somatic cell score (SCS) were estimated. About 1193 measurements were included in the analysis for each character of 358 ewes of 9 genotypes. Nine breeds and genotypes were included in these experiments: purebred Improved Valachian (IV), Tsigai (T), Lacaune (LC) ewes, and IV and T crosses with a genetic portion of Lacaune and East Friesian (EF) - 25 %, 50 % and 75 %. Primary data were processed using restricted maximum likelihood (REML) methodology and the multi-trait animal model, using programs REMLF90 and VCE 4.0. Heritability coefficients for somatic cell count were low: h2=0.03, for LOGSCC h2= 0.08 and for somatic cell score h2=0.06. Somatic cell score can be considered for inclusion in a breeding program aimed at reducing somatic cell count and frequency of clinical mastitis in dairy sheep.
Economic weights of somatic cell score in dairy sheep