The effects of supplemented selenium and vitamin E on a number of rumen parameters such as the population of rumen protozoa, pH, concentration of volatile fatty acids and ammonia nitrogen in the rumen content were studied. In addition, the lambs were weighed at the end of experiment. The total counts and percentage proportions of rumen protozoa, the pH value, and the levels of ammonia nitrogen and volatile fatty acids were determined in the samples of rumen content. However, there was no statistically significant difference between the two groups in ammonia nitrogen levels. Combined selenium and vitamin E supplementation of the lambs ration caused an increase in the levels of volatile fatty acids, total counts of protozoa, and body mass gain while decreasing the pH value of the rumen content.
Zoonoses are diseases, the infections of which can be transmitted between man and animals.
Only a few are of importance with respect to poultry meat and meat from cattle, sheep, horses and goats. Advances in the control of diseases such as tuberculosis, brucellosis and trichinosis in animals have reduced the hazards posed to workers in the meat industry and to consumers of meat. This applies particularly to bacteria such as Campylobacter , Salmonella , verotoxigenic and other pathogenic Escherichia coli and Yersinia . Protection of meat workers from infection depends upon taking normal hygienic precautions, which also protect the meat from contamination from the workers. Consumers are exposed to a smaller range of zoonoses than meat workers because they encounter only meat that has passed inspection.