The impact of early and mid-pregnant Hu ewes’ dietary protein and energy levels on growth performance and serum biochemical indices

ABSTRACTThis study explored the effects of different protein and energy levels on growth performance and serum biochemical indices of ewes during early and mid-pregnancy. A total of 132 ewes were assigned to 5 groups (P1, P2 = E2, P3, E1, E3) to dietary protein levels (P1: 9.22%, P2: 10.04%, P3: 10.86%) and dietary energy levels (E1: 9.04 MJ/kg, E2: 9.53 MJ/kg, E3: 10.02 MJ/kg). Blood urea nitrogen (BUN) increased with an increase in protein levels in early pregnancy (P = .008). In the P2 group, creatinine, triglyceride, and lactate levels were lowest and total protein levels were highest in mid-pregnancy (P < .05). Final weight, total weight gain, and average daily weight gain increased with an increase in energy levels of ewes (P < .05). BUN, aspartate transaminase, cholesterol, and high-density lipoprotein decreased with an increase in energy levels in mid-pregnancy (P < .05). Alanine aminotransferase, lactate dehydrogenase, and glucose increased initially and then decreased with an increase in energy levels (P < .05). To sum up, we suggest that Hu sheep be fed diets with energy and protein levels of 10.02 MJ/kg and 10.04% in early and mid-pregnancy, respectively.