Abstract:
The studies presented in this dissertation were designed to investigate the performance of dromedary camels under improved management condition based on two sets of experiments conducted in the long dry season (September - December). The first set evaluated milk yield and chemical quality of camels milk grazing/browsing natural pasture only (Control) and supplemented with Low (0.25 kg./kg milk), Medium (0.5 kg/kg milk) and High (0.75 kg/kg milk) level of concentrate. The second set of experiment dealt with growth, carcass characteristics, physicochemical quality of meat and physico-mechanical and chemical quality of hide and leather of male camels fed with urea treated maize stover basal diet and supplemented with Low (0.5%), Medium (1%) and High (1.5% body weight) levels of concentrate under feedlot condition. Medium and High level of dietary supplement increased milk yield (11.4 ± 0.75 kg and 11.3 ± 0.71kg, respectively) compared to the Low (8.65 ± 0.52 kg) level and the Control (5.55 ± 0.31 kg) treatment. Whereas milk fat content was higher for Medium level (4.15%) than the Low (3.70%) and the Control (3.79%) treatment. High level of concentrate showed superior body weight gain (BWG) compared to the other three levels while the High and the Medium level recorded higher body condition score (BCS) gain of the lactating camels compared to the other two levels. Dietary supplementation only showed higher milk FA values for palmitoleic acid. The top to bottom sequences of the four abundant FAs of the camels‘ milk were oleic, palmitic, stearic and myristic acid. The fattening camels supplemented with Medium and High level of concentrate recorded more daily weight gain (0.79 ± 0.01 kg, 0.84 ± 0.01 kg), dressing percentages (66 ± 0.005, 66 ± 0.004%) and rib eye area (42.3 ± 1.55, 43.6 ± 2.29cm2), respectively, than the Low level group (0.68 ± 0.06 kg, 61 ± 0.01%, 34.4 ± 0.99cm2). Feed conversion efficiency was superior for the Medium (7.21 kgDM/kg gain) as compared to the Low level (8.05 kgDM/kg gain) but as good as the High (7.68 kgDM/kg xv gain) level. Higher hot carcass weight (155 ± 17.6 kg) was obtained from High level concentrate group than the Low level (129 ± 13.4 kg). High and Medium level of supplementation produced more lean, fat and boneless meat than camels with Low supplemental level. The muscle proportion of most wholesale cuts was higher for the Medium and High level groups than the Low level groups. Low and High level groups displayed higher pH values as compared to the Medium level group. The meat from Medium and High level had higher water holding capacity than the Low level supplement while the Low level supplement exhibited more cooking loss than the Medium and High level. Medium level supplement exhibited higher protein value than the meat from Low and High level supplements, whereas meat from Low level supplement showed lower fat value than meat from the Medium and High level groups. Effect of supplementation was not observed on the fatty acid (FA) profile of the meat. The top four abundant camel meat FAs in an ascending order in the current experiment were the oleic, stearic, palmetic and myristic acid. As to the hide and leather quality, tear load and tear resistance perpendicular to the backbone of crust leathers was higher for Medium level groups compared to the Low level while the arithmetic mean of the parallel and the perpendicular tear were higher for Medium and High level supplements compared to the Low level. Tear resistance of finished leather was higher for High level supplement groups compared to the Low and Medium level. The chemical qualities of the hide and leather were not affected by supplementation. In conclusion, the overall results show that higher level of supplementation exhibited a greater capacity for improved milk production and quality and meat yield and quality as well as physico-mechanical quality of hide and leather of dromedary camels. But, with regard to economic efficiency of milk production the Low level supplementation was better than the other dietary levels.