Lactation performance of Awassi ewes fed diets containing either Atriplex halimus L. or olive cake

Abstract

The objective of the two studies was to evaluate t effects of feeding on lactating Awassi ewes (study 1) and lambs (study 2), fed on a diet of Atriplex halimus L. (ATR) or olive cake (OC), as a foraging source substitute for wheat straw. In study 1, 33 newly lambed ewes and their lambs were randomly assigned one of three diets: The control diet (CON), 250 g/kg of OC, or 250 g/kg of ATR dry matter (DM). Ewes and lambs were housed in individual pens. Ewes fed CON diet had greater DM, neutral detergent fibre, and acid detergent fibre intakes than OC and ATR groups. Ether extract (EE) intake was greater (p < .0001) in OC diet compared to CON and ATR diets. Milk yield was similar (p = .99) among treatments. Content of milk total solids and fat were greater in ATR diet than CON and OC diets. Milk production cost was lower in the OC and ATR compared to the CON group. In study 2, 18 ewe lambs were assigned the same diets used in study 1 to evaluate the effects of OC and ATR on nutrient digestibility and N balance. Dry matter digestibility was greater in ATR compared to CON and OC groups. The digestibility of EE was greater in the OC group than in CON and ATR groups. Results showed that the inclusion of OC and ATR did not negatively impact lactation performance. Additionally, results proved the economic value of using such products, as they reduced the cost of milk production. Highlights Olive cake and Atriplex halimus L. were fed to Awassi ewes at a level of 250 g/kg of dietary DM. The inclusion of olive cake and A. halimus L. at 250 g/kg of dietary DM, as a source of fibre, did not negatively impact the lactation performance of sheep. Additionally, results proved the economic value of using such products, as they reduced the cost of milk production.