Evaluation of digestibility and feed intake of a date palm by-products diets fed to Awassi rams

摘要

A digestibility experiment data of 36 observations of 6 animals during 6 successive days fed two iso-caloric and iso-nitrogenous totally mixed diets (TMD) were analyzed to evaluate digestibility and voluntary feed intake of date palm by-products . The first diet (NCD) formulated based on crushed palm fronds and date waste, whereas the second diet (CD) based on barley grains and crushed Rhodes hay. Animals used were adult Awassi rams (3 animals for each diet treatment) of similar body weight ( 51.8 ± 1.47 kg) . Animals were accommodated in individual digestibility crates and fed the experimental diets for 30 days of which 24 days for adaptation and 6 days for data collection. Daily feed intake, fecal and urine outputs were measured. Blood samples were collected daily. Chemical composition of feed and feces and urine nitrogen content and serum blood metabolites levels were determined. Digestibility coefficients, nitrogen balance parameters and blood metabolites levels were examined for significance of differences between the 2 experimental groups using unpaired student t test. Results indicated that NCD fed rams consumed daily significantly (P0.05) higher amount of dry matter, DM (2110.9 g vs.1894.6 g), crude fiber, CF (420.1 g vs. 325.9 g), crude protein, CP (529.8 g vs. 447.1) and ash (213.2 vs. 158.1 g) but significantly (P0.05) lower amount of ether extract, EE (10.6 g vs. 24.6 g) than those of CD group. NCD group had significantly (P0.05) higher ash digestibility but had (P0.05) lower EE digestibility and metabolizable energy of feed (9.7 MJ/kg DM vs. 10.4 MJ/kg DM) than CD group. NCD rams group significantly (P0.05) excelled CD group on retained nitrogen amount and as percentages of nitrogen intake or digestion. For blood metabolites levels, the difference between diet treatments was significant only for total cholesterol and its derivatives, where CD group always had higher values than NCD group . This study demonstrated that the non-conventional date palm by-products-based diet (NCD) proved to be highly palatable and well consumed by sheep. It is also well digested and converted into body weight gain.