Effects of Lactation Stage and Parity on Milk Yield, Composition and Properties of Organic Sheep Milk

Abstract

Novotna, L., Kuchtik, J., Sustova, K., Zapletal, D. and Filipcik, R. 2009. Effects of lactation stage and parity on milk yield, composition and properties of organic sheep milk. J. Appl. Anim. Res., 36: 71–76. Effects of lactation stage (LS) and parity (PA) on daily milk yield (DMY), composition, properties and rennet curd quality (RCQ) of organic sheep milk were evaluated using 10 crossbred ewes reared on an organic sheep farm. Both LS and PA as well as the interaction of LS × PA had a significant effect on DMY and the contents of total solids, fat, protein, casein and lactose. The DMY for the whole lactation increased with the order of lactation. LS, PA and the interaction of LS × PA also had a significant effect on all milk properties as well as the RCQ. In the course of all lactations, titrable acidity (TA) kept increasing. It was found that the higher the values of titrable acidity, the longer the rennet clotting time became and RCQ became worse.