Effect of water restriction on milk yield and quality in Lacaune breed ewes

Abstract

The effect of water restriction on body weight, body condition score, milk yield, and milk composition and rheological characteristics in intensively reared Lacaune ewes was evaluated. After 7 days of adaptation, the trial lasted 28 days. Thirty lactating ewes (48 ± 5 months of age; mean value ± standard deviation) at the beginning of third lactation month were divided into three groups (n = 10), corresponding to the following water restriction treatment: a group control received no drinking water restriction (W100), and two groups received water to the extent of 80% and 60% of W100 daily consumption (W80 and W60 group respectively). The effects of water restriction were assessed at the beginning of experiment (D0), at D14 and D28. The W60 group resulted in a significant decrease in body weight, body condition score, milk yield and feed consumption of hay due to the experimental treatment; whereas a marked increase in both W60 and W80 groups of milk lactose, urea, sodium, sodium chloride content and titratable acidity was observed. Rheological parameters of milk, rennet coagulation time and curd-firming time were positively affected by water restriction treatments, with a decrease in both experimental groups of the time required for the formation of a stable and firm curd. Results highlight the importance of water consumption in dairy sheep. The scarce availability of water, significantly affecting ewes milk production, is worthy of particular attention in arid area where water stress-resistant breeds should be considered. This study underlines that milk yield, being closely linked to the availability of water of the breeding habitat due to its high water content (about 81%), could be reached in area where water is not a limiting factor without reducing the genetic expression of the animals. Less severe water restrictions, such as 20% of daily voluntary water intake, produce no detrimental effect on milk yield.

Morphophysiological Responses of the Goat Mammary Gland to Water Scarcity in Arid and Semi-Arid Environments: Are They Enough to Generate Adaptation to New Climatic Challenges?

“…Finally, it is noteworthy that in contrast to goats, camel BW loss is less (9% vs. 35%) [25,27]. A decrease in milk production of 11.6% and 16% has been observed in sheep and cattle that consume 60% of their daily water requirement [34,35].…”

Malnutrition of pregnant beef cows and the impact on passive immunity transfer to calves

“…There is a scarcity of studies evaluating the direct impact of water restriction on colostrum yield and the transfer of passive immunity in ruminants, and almost no information on the impact on rangeland beef cows. It has been recognised that severe water deprivation reduces milk production in other lactating ruminants, such as dairy cows (Golher et al 2021), sheep (Chedid et al 2014;Casamassima et al 2018) and goats (Aganga 1992), and that the reduced milk yield is part of the survival mechanism, which is likely to be caused by a combined effect of lower DM intake and changes in blood osmolarity (Olsson 2005; Ocak Yetisgin and S ¸en 2020). In dairy cows, a decline of 50% in voluntary water intake resulted in a 26% reduction in milk yield (Little et al 1980).…”