Effects of partial replacement of dietary protein by a leaf meal mixture on nutrient utilization by goats in pre- and late gestation

This study examined the comparative nutrient utilization of indigenous non-descript goats (n = 12) maintained on a basal diet of wheat straw supplemented with a concentrate based on either soybean meal (SBM) or Leucaena leucocephala–Morus alba–Azadirachta indica (2:1:1) leaf meal mixture (LMAM) prior to conception (pre-gestation), and during gestation (n = 8) in a completely randomized design. Concentrate represented 42% and 72% of DM in diet before and during pregnancy, respectively. Therefore, the plane of nutrition and nutrient density in terms of digestible CP and TDN of composite diets offered to does during late gestation were significantly higher relative to non-pregnant does. Intake of DM was significantly higher (P < 0.001) in does during late gestation as compared to their intake during pre-gestation. The digestibility of nutrients and N balance data were comparable (P > 0.05) among goats irrespective of dietary supplements. However, does in late gestation had higher (P < 0.001) nutrient digestibility of DM, OM, and CP and lower digestibility of NDF, ADF, and cellulose as compared to non-pregnant does due to higher dietary ratio of concentrate. Similarly, pregnant does had significantly higher (P < 0.001) intake, excretion and retention of N during late gestation irrespective of diets. The nutritive value of composite diets and plane of nutrition of does were similar (P > 0.05) irrespective of dietary treatments. Apparently, the supplementation of wheat straw either with LMAM or commercial type concentrate containing soybean meal resulted in similar performance of does; the leaf meal mixture could contribute up to 36% of the total DMI in gravid does without any adverse effect on their general health and reproductive performance.