ABSTRACT
Keywords: Acacia saligna – Cassava – Economic efficiency- Growing Sheep
INTRODUCTION
Feed resources deficiency considers one of the basic constraints to improve animal production in arid and semi-arid regions of Egypt. Improving nutritional status of livestock graze in desert (sheep, camels and goats), particularly during the prolonged dry seasons, could increase the average annual animal production by approximately 27%. Attention directed towards the necessity of utilizing the marginal resources, i.e. saline soils and underground water for producing unconventional animal feeds. The native natural rangelands constitute the principal feed resources in the Egyptian deserts. They are widely distributed throughout several regions of Egypt due to presence of numerous salines along the Mediterranean and Red Seas shores and inlands). Halophytes represent a major part of the natural range, particularly perennials and shrubby ones. The less and unpalatable plant species represent approximately 70% of the total coverage. Several attempts made towards utilization of such low value or unpalatable halophytic plants through proper processing methods to improve their palatability and nutritional utilization. Under semi-arid area condition, small ruminant fed on trees and shrubs such as Cassava and Acacia to solve the attendant problems of low productivity (El Shaer
This research was performed to study the effect of feeding ammoniated wheat straw and its mixture with Cassava or/and Acacia Saligna on methane emission and growth performance of Barki lambs under semi-arid condition. The study conducted at Animal Production Research Station, Borg El Arab, belonging to Animal Production Research Institute, Agricultural Research Center, Egypt. A total number of twenty five Barki lambs were randomly allocated into six groups. These animals often depend on low quality crop residues and limited feed supplement. Egyptian desert consider a source of tannin-ferrous plants (TFP) along the year. These plants had lot of nutritive problems need to solve before depending on them as a fodder. In vitro experiments conducted to evaluate the effect of several mixtures of TFP with urea treated wheat straw (TWS) on dry matter degradation, ammonia-N and methane production. Six treatments were examined(G1) CFM+ Acacia Saligna (A): TW Sat (50:50), (G2) CFM+ Prosopis Juliflora (P): TWS at (50:50), (G3) CFM+ Cassava (C): TWS at (50:50), (G4) CFM+ A: P: TWS at (25: 25: 50), (G5) CFM+ A: C: TWS at (25: 25: 50) and (G6) CFM+ P: C: TWS at (25: 25: 50), respectively. Samples of each forage type collected after 0, 3, 6, 12 and 24 h of incubation for determination of cumulative gas production. In addition, thirty growing male Barki lambs, aged average 3 months were used to study the effect of the tested rations on growth performance. The results showed that the condensed tannin (CT) content ranged from 20 (A: C: TWS –G5) to 30 g/kg DM (Acacia saligna). Methane production per unit of fermented DM was inversely related to protein solubility. G1showed a lower (P<0.01) ruminal NH3-N concentration which associated with the decrease (P<0.01) in rumen protein degradability. After 24 h of in vitro incubation, CH4 production was17, 18, 17, 15, 13 and 14 ml, for all groups, respectively. Daily body gains were significantly affected by tested rations. The highest values recorded with G 5. Consequently, consumption of combination of TFP containing various classes of secondary components with resource of NPN leads to reduce CH4 emission from ruminants and improve lamb growth performance.