Effect of lactation stage, parity and season on physico-chemical properties and microbial quality of goat milk under smallholder farmers in Abergelle district Tigray, Northern Ethiopia

Abstract

Goat milk is the most nutritious milk but susceptible to microorganisms. Goat milk in Tanqua Abergelle of Tigrai has been used traditionally and its level of quality affected by several factors. However there is limited knowledge on the factors affecting its quality. The objective of this study was to assess the physico-chemical properties and microbial quality of goat milk at different lactation stages, parity and season. A total of 80 Abergelle dairy goats were selected to collect 240 milk samples for analysis of Milk Density, Milk Composition, level of mastitis Esertia coli, Staphylococcus aureus and Somatic Cell Count (SCC) in three early, mid and late lactation stages, two parities and rainy and dry seasons. The study was arranged in factorial and Duncan’s multiple- range test method were used for mean separation at P<0.05. The study indicated, milk density was higher (p<0.05) in late lactation than early and mid-lactation. Whereas fat content was not significantly affected however numerical lower in early-lactation than the mid and late lactation, on the other hand SNF was stable between mid and late lactation. The milk microbial content, SCC and E-coli increased with increasing parity. The highest microbial level , SCC and E-coli content was recorded for early lactation and late lactation. The results from this study shows that microbial quality and physico-chemical properties and were not affected by season. Season didn’t affect, Moreover, parity and stage of lactation didn’t affect physico-chemical properties and microbial quality. The current study showed that goat milk quality and hygiene is affected by stage of lactation but not by season and parity. These result indicated that goat milk microbial quality may help to precisely implement milk hygiene and handling intervention under smallholder goat producers.