EVALUATION OF NON-CONVENTIONAL ENERGY AND PROTEIN SOURCES IN LACTATING EWES’ RATION

Abstract

This study was conducted to evaluate using of some non-conventional feed resources such as Leucaena leucocephala (leucaena), Manihot esculent (cassava) leaves, and rejected banana (RB) in lactating ewes’ diet. This study consisted of three parts; the chemical evaluation, in vitro and in vivo studies. The chemical composition, HPLC analysis and GC-MS analysis were performed for the tested ingredients. The in vitro study was conducted using gas production technique, to evaluate the rate of gas production and fermentation patterns at 24 hrs of incubation. Regarding the in vivo studies two separately lactation trials were conducted using lactating Blackbelly ewes (1 week after lambing). In the 1st lactation trial, 24 ewes were divided randomly into four groups to evaluate the total replacement of alfalfa pellets with leucaena leaves pellets with/without RB. In the 2nd lactation trial, another 24 ewes were divided randomly into four groups to evaluate the total replacement of alfalfa pellets with cassava leaves pellets with/without RB. The chemical analysis showed that leucaena and cassava leaves had higher crude protein (22 and 20.5%), total phenols (40.7 and 22.1 eq- to Gallic acid (g)/DM (kg)), and total tannins (4.43 and 1.79%) than alfalfa. The HPLC results mentioned that leucaena and cassava leaves extract had high content of valuable phenolic components that have antioxidant and anti-inflammatory properties like gallic acid, ellagic acid and naringenin. The in vitro study demonstrated that leucaena leaves had the lowest total accumulative gas production being 90.7 ml/g DM. The RB recorded the lowest ruminal pH (5.24) and ammonia concentration (9.0 mg/100ml) compared to other feed ingredients, while it had the highest gas production (192.9 ml/100ml) and degraded organic matter (905.3 g/kg). The 1st in vivo trial illustrated that there were insignificant differences in total DM intake as well 4% fat corrected milk and milk yield and composition between different diets. The 2nd in vivo trial indicated that there were insignificant differences in forage pellets intake, however RB addition decreased grass hay intake being 1317.5 g DM/day comparing with diets without RB (1441.3 g DM/day), with insignificant difference in 4% fat corrected milk, milk yield and composition. Addition of RB to diets showed a positive effect (insignificant) on ewes’ milk yield. In general, substitution of alfalfa by leucaena or cassava leaves with RB as non-conventional protein and energy sources in ration detected no depressive effect on lactating ewe’s performance and lambs growth rate. Key words: Leucaena leucocephala, Manihot esculent, rejected banana, Medicago sativa L., Dichanthium spp., in vitro, in vivo.