Partial substitution of barley grain with Prosopis juliflora pods in lactating Awassi ewes’ diets: Effect on intake, digestibility, and nursing performance

A study was conducted to evaluate the effects of feeding Prosopis juliflora pods (PJP) on performance of nursing Awassi ewes and their lambs. Thirty Awassi ewes and their lambs were randomly assigned to one of the three dietary treatments being no PJP (PJP0; n = 10), 125 g/kg PJP (PJP125; n = 10), and 250 g/kg PJP (PJP250; n = 10) of the diets offered ad libitum in replace of the barley grain. The study lasted for 8 weeks. No differences occurred (P > 0.05) in dry matter (DM), organic matter (OM), crude protein (CP), and metabolizable energy (ME) intake among groups. However, neutral detergent fiber (NDF) was higher (P < 0.05) for PJP250 than PJP0 diet, while PJP125 group was intermediate. Moreover, acid detergent fiber (ADF) intake was the highest (P < 0.05) in the PJP250. Intakes of NDF and ADF also increased linearly (P < 0.05) with increasing PJP content. Digestibility of DM, OM, CP, and NDF was similar among diets but ADF digestibility was lower (P < 0.05) in the PJP250 than the PJP0 diet. There were no differences in final body weight (BW) of ewes among groups. Awassi ewes fed the PJP0 diet lost less (P < 0.05) BW than ewes fed the PJP125 and PJP250 diets. Lambs fed the PJP125 and PJP250 diets had higher (P < 0.05) weaning BW and average BW gain than the PJP0 treatment group. Similarly, weaning BW and average BW gain increased linearly (P < 0.05) with increasing PJP content. Ewes fed the PJP250 diet had higher (P < 0.05) milk production than ewes fed the PJP0 and PJP125 diets with no differences among treatment groups in total solids, fat and protein content. Awassi ewes that received PJP250 diet had lower (P < 0.05) kilogram DM intake: kilogram milk production than PJP0, while PJP125 group was intermediate. Cost/kg milk production (US$) was the highest (P < 0.05) in PJP0 group compared with PJP125 or PJP250 groups. Results demonstrate the potential of including PJP as a feed ingredient for nursing Awassi ewes and their lambs due to the reduction in feed cost and the improvement in milk production.