Livestock Nutrition

Biography

Biography: Nazik Eisa

Abstract

Forty eight Sudan desert lambs were used in a-2month fattening trial to evaluate the effect of natural gastro-intestinal parasitic infection on fattening performance of old (2 years) and young (milk teeth) lambs fed iso-nitrogenous high (12.24 MJ/kg) high and low (10.35 MJ/kg) energy diets. Average daily gain, final body weight and total body weight gain showed a significantly (P< 0.001) high differences. Infection along with low energy played a very important role resulting the worst performance plus high mortality. Significant differences were recorded in slaughter weights, the highest one was that of old lamb group, treated for internal parasites and given high energy diet (39.67kg). It was 40.76% higher than the lowest treatment group which was the young infected given low energy diet. Empty body weight, dressing percentage and muscle percentage were (P< 0.05) higher in the treated groups. carcass weight, carcass characteristics, whole sale cuts, loin composition. No significant differences concerning evaporation ratio, Meat physical and chemical attributes plus non carcass components except for alimentary tract fill and full rumen (P< 0.01). Significant differences in carcass characteristics were recorded, carcass weight of old lambs treated for internal parasites and given high energy diet was 9.86% higher than their counterpart left naturally infected. Both hot and cold empty body weights and dressing percentages were greatly affected by internal parasitic infection and dietary energy level. The best dressing percentage was for the old lamb group treated for internal parasites and offered high energy diet which was 56.59% (based on empty body weight) while that of old infected group fed low energy diet was only 44.13%. Carcass and wholesale cuts yields were not significantly affected. Muscle percentage was significantly (P< 0.05) higher in the treated groups whether given high or low energy diet than their counter part contr. Gut and rumen fills increased significantly (P< 0.01) in the low energy groups whether treated or left naturally infected, but they were higher in the treated groups. Foregut fill percentage of the treated low energy group was 24.97% while their counterpart control group was 15.97%. Physical and subjective meat quality attributes and meat chemical compositions were not significantly affected. Postmortem of slaughtered and dead lambs revealed severe damage of the internal organs. Parasitic infection decreased in 25% of the infected lambs and no egg shed was detected, however 25% of the infected lambs died and fifty percent of the lambs remained infected until the end of the experiment. Weekly evaluation of blood glucose level revealed no significant differences between treatments. Margin percent of sales of old lamb group that was treated for internal parasites and fed high energy diet was 23.80% while that of old group of lambs that was left naturally infected and fed low energy diet lost 10.18% of their total cost. Although the group of young lambs treated for internal parasites and given high energy diet came in the second rank in term of performance, but they achieved the best profit (5.7%) more than the profit of group of old lambs treated for internal parasites and given high energy diet because they consumed less dry matter. Due to the intensification of dairy herds and the recognition of clinical and subclinical infections with a negative impact on performance as disease, study of the effect gastrointestinal (GI) nematodes in Sudan desert sheep is becoming urgent. The objectives of this paper are to review the aspects related to the effect of gastrointestinal (GI) nematodes regarding feedlot performance and carcass characteristics taking in consideration age and dietary energy level and blood glucose level.