Feeding corn silage improves nursing performance of Awassi ewes when used as a source of forage compared to wheat hay

The objective of this study was to evaluate the effect of using corn silage (SILAGE) or wheat hay (HAY) as a source of forage on nursing performance of Awassi ewes. Forty ewes (body weight; BW=43.5±1.58kg) and their single lambs (BW=6.3±0.28kg) were randomly assigned to two diets; SILAGE vs. HAY (four pens/diet; five ewes/pen). Concentrate feeding was restricted to 1.1kg dry matter (DM)/ewe/d, whereas forage was offered ad libitum. The study lasted for 56d (7d of adaptation and 49d of data collection). Ewes and lambs were weighed after the adaptation period and at the end of the study. Milk yield and blood samples were collected on days 9, 16, 23, 30, 37, 44 and 51. Intakes of forage and total DM were greater (P<0.05) in SILAGE-fed ewes compared to those fed HAY. Additionally, intakes of crude protein, ether extract and net energy were also greater (P≤0.002) in the SILAGE group. However, neutral and acid detergent fiber intakes were greater (P=0.022) in the HAY than in the SILAGE group. Average daily gain was greater (P=0.032) in the SILAGE than the HAY group. Circulating glucose concentration was greater (P=0.023) in the SILAGE treatment compared to the HAY group, while serum urea nitrogen was similar (P=0.914) in both groups. Milk, total milk solids, protein and fat yields were greater (P<0.05) in the SILAGE than in the HAY group. Dietary replacement of wheat hay with corn silage to early lactating Awassi ewes improved feed intake, yields of milk and milk components, ewe body weight, and lamb average daily gain.