Changes in milk yield and composition after lamb weaning and start of machine milking in dairy ewes
2013
Antonič, J., Slovak Univ. of Agriculture in Nitra (Slovak Republic) | Jackuliaková, L., Slovak Univ. of Agriculture in Nitra (Slovak Republic) | Uhrinčať, M., Animal Production Research Centre, Nitra (Slovak Republic) | Mačuhová, L., Animal Production Research Centre, Nitra (Slovak Republic) | Oravcová, M., Animal Production Research Centre, Nitra (Slovak Republic) | Tančin, V., Slovak Univ. of Agriculture in Nitra (Slovak Republic)
Stress from weaning may cause problems with milk ejection resulting in remaining milk in alveolar part of the udder and thus changing the milk composition. It is important to know current health status of the udder immediately after lamb removal. The aim of this study was to determine changes in milk composition during first three milkings after lamb weaning and especially the frequency of distribution of ewes differed by somatic cell count (SCC). The study was performed on 36 lactating dairy ewes of two breeds - Tsigai and improved Valachian within first three milkings after their lambs were weaned. Totally, 108 milk samples were collected for analysis. on the basis of SCC the animals were divided into three categories: low – SCC less than 0.5×106 cells per ml , middle – 0.5×105 less than SCC less than 106 cells per ml, high – SCC more than 106 cells per ml. There were 64 percentages of ewes classified to low SCC category, 8 % - to middle and 28 % - to high SCC category at first milking after weaning. The average SCC was 5.39 plus minus 0.70 log10 per ml at first milking, 5.66 plus minus 0.73 log10 per ml at second, 5.68 plus minus 0.65 log10 per ml at third and 5.26 plus minus 0.61 log10 per ml at fourth milking. Significant negative correlation of SCC with lactose content (r= -0.467) and total milk yield (r= -0.196) and order of milking and lactose (r= -0.319) was found out. in conclusion, higher percentage of ewes with high SCC during first milking indicates health problems of the udder at the end of suckling period, and increasing SCC during next two milking could by caused by stress from weaning and starting of machine milking.
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