Beef longissimus dorsi steaks were treated with 10, 25, and 50-kGy gamma irradiation and weekly examined during refrigeration storage at 5ºC to evaluate the changes in their organoleptic, bacteriological, chemical and nutritional quality characteristics as well as deterioration criteria. The signs of spoilage became apparent after 17 days of refrigeration storage in control untreated samples compared with 52 days for 10 kGy treated samples; however, samples treated with 25 or 50 kGy remained without signs of spoilage until the end of storage period (4 months). A characteristic burnt flavor was distinguished in irradiated beef samples, which was intensified with high irradiation dose, but decreased during storage. High doses of irradiation especially 50 kGy resulted in a brownish color of meat surface. Moreover, gamma irradiation resulted in high thiobarbituric acid values after treatments and during storage due to lipid oxidation. Thiamin content of beef was severely reduced and the reduction was dependant on the irradiation dose. Riboflavin was also affected by irradiation, but it was much stable than thiamin. The proximate chemical composition of beef was slightly affected by irradiation.

In this study a total of 14 infected sheep and 6 lactating albino goats were used. These animals were proved to be brucellosis seropositive using TAT, MET, BAPAT, RBPT and rivanol test as well as bacteriologically positive by isolation of Brucella melitensis biovar 3 from their milk. These animals were subjected to trials of treatment using three different methods. Goats treated by antibiotics combined with BCG showed the highest recovery rate (on bacteriological basis), followed by animals treated with antibiotics only and finally animals treated with antibiotics combined ID. The recovered treated animals were placed under careful investigation for 2 years with no evidence of Brucella infection neither in them nor in their newborns.

Considerable difficulties are associated with the isolation of Yersinia enterocolitica from food particularly milk and milk products. Most methods are time consuming require enrichment steps and are unable to differentiate pathogenic isolates from non pathogenic ones. The purpose of this study was to evaluate the detection of Yersinia enterocolitica in milk by both polymerase chain reaction (PCR) and conventional culturing methods. Fifty milk samples were collected from Shami goats in North Sinai governorate. Two primers (DG26 and DG63) were used in PCR and the size of the PCR-product was 440bp. The results obtained by PCR technique were in good agreement with that obtained by conventional culturing method. Five samples (10%) were positive by PCR while 4 samples were positive by conventional culturing method. Interestingly, PCR results are obtained within few hours. Moreover, it solved the problem of interpretation of classical biochemical and serological typing in one step without necessity of using additional examinations. This makes diagnosis in food control laboratories much faster and more efficient.

The lectin-binding characteristics of the epithelial lining of the thoracic air sacs of the chicken were determined. Con A, LCA and PSA bound to the apical membrane as well as to the cytoplasm distal to the nucleus of the surface epithelium, indicated the presence of a-linked mannose as well as Nacetylchitobiose- linked a-fucose residues in the glycoproteins. GSL I bound to the apical membrane and cytoplasm distal to the nucleus, but not to the cilia of the epithelium, where-as MPL, DBA and RCA120 bound to the apical membrane, cilia and cytoplasm, indicated the presence of a-linked Nacetylgalactosamine residues. However, neither SJA or SBA showed any binding, indicating the absence of b anomers of galactosyl (b1.3)N-acetylgalactosamine and b-linked N-acetylgalactosamine residues. UEA I bound to the apical membrane and cilia, as well as to the cytoplasm of a few cells, indicated the presence of a-linked fucose residues. PNA bound to the apical membrane of some, but not all, surface epithelium cells, indicated the presence of galactosyl (b1.3)N-acetylgalactosamine residues. WGA bound to the apical membrane and cilia, as well as to the cytoplasm of a few cells, indicated the presence of neuraminic acid residues.

Poisoning with cardiac glycoside-containing plants is collectively the most important plant-associated poisoning of livestock in southern Africa. As a diagnosis of this significant poisoning is currently based on circumstantial evidence, a practical chemical procedure indicating the presence of cardiac glycosides in plants and animal specimens would be of considerable benefit. The fluorescence polarization immunoassay (FPIA) method, used to determine digoxin plasma levels in humans and dogs, was adapted to estimate cardiac glycoside levels in known cardiac-glycoside- containing plants as well as in the rumen and organs of dosed sheep. Positive FPIA values were obtained with bufadienolide-containing plants, while negative results were obtained with plants not known to contain cardiac glycosides. The FPIA has aided in the diagnosis of cardiac glycoside poisoning in livestock and game in 30 outbreaks examined at the Division of Toxicology, Onderstepoort Veterinary Institute. Each outbreak is briefly described. As a result of this assay, a better understanding of cardiac glycoside poisoning has been reached.

The concentration of organochlorines (OCs) such as organochlorine pesticides and polychlorinated biphenyls were measured in adipose tissue collected from 14 male hippopotami at Mfuwe in the southern part of the Luangwa National Park, Zambia. The samples contained low levels of OCs, and the concentrations of OCs were comparable to or lower than reported for wild herbivores studied in other parts of the world.

Rhizome extracts of Gunnera perpensa are used in traditional remedies in South Africa to treat endometritis both in humans and animals. An investigation was undertaken to determine whether this plant possesses antibacterial activity, which may explain its efficacy. Gunnera perpensa rhizome extracts were prepared serially with solvents of increasing polarity and tested for antibacterial activity. Test bacteria included the Gram-positive Enterococcus faecalis and Staphylococcus aureus and the Gram-negative Escherichia coli and Pseudomonas aeruginosa. A moderate to weak level of antibacterial activity in most of the extracts resulted, with the best minimal inhibitory concentration (MIC) value of 2.61 mg ml-1 shown by the acetone extract against S. aureus. The extracts were also submitted to the brine shrimp assay to detect possible toxic or pharmacological effects. All the extracts were lethal to the brine shrimp larvae at a concentration of 5 mg ml-1. The acetone extract was extremely toxic at 1 mg ml-1, with some toxicity evident at 0.1 mg ml-1. The remainder of the extracts generally displayed little activity at concentrations lower than 5 mg ml-1. In summary, the results indicate that although the extracts demonstrated a level of pharmacological activity, the relatively weak antibacterial activity is unlikely to justify the use of G. perpensa rhizomes in the traditional treatment of endometritis. Rather, the slightly antibacterial nature of the rhizomes may contribute to an additive effect, along with their known uterotonic activity, to the overall efficacy of the preparation.

A penta-dog inactivated cell culture vaccine was prepared to protect dogs against canine distemper virus, canine parvovirus, canine adenovirus1, 2 and rabies virus. The potency of this vaccine was compared with that of single inactivated vaccines prepared against each disease, in different groups of susceptible dogs. It was found that the protective dose of penta-dog vaccine (2ml) including the protective amounts of the five viral proteins resulted in full protection of vaccinated dogs against the challenge with virulent strain of the used viruses showing no antagonizing effect between each other with and no adverse postvaccinal reaction. So, the prepared inactivated cell culture penta-dog vaccine is a safe and potent vaccine for dogs which resulted in saving time, cost, and effort stress factors on animals and providing good immune statues.

In this study, two methods for determination of formalin amount were applied on samples of inactivated vaccines representing local or foreign companies. The first method; matching method was conducted by using phenyl hydrazine while in the other method is; spectrophotometry phloroglucinol was used. Spectrophotometrical method was found more sensitive and more accurate than the matching one. At the same time, the spectrophotometry method could be used for determination of formalin in all inactivated vaccines either bacterial or viral vaccines.

The incidence of E. coli O157, Salmonella typhimurium, Listeria monocytogenes, and Yersinia enterocolitica were studied in some locally produced cheeses. Thirty samples of each kind of the cheese were tested for the presence of some pathogens, which are frequently associated with food born disease. E. coli O157: IMS; Listeria monocytogenes were enumerated on modified Oxford agar; Salmonella was enumerated using standard procedures from Dynal manual using anti-Salmonella antibodies. Y. enterocolitica was enumerated on Yersinia selective agar base. Romano and processed cheese were found to be free from all tested pathogens but Kareish and Feta cheese were found to harbor E. coli and Y. entertocolitica. The results indicated the presence of some food borne pathogens in our food supply. Certain types of locally produced cheese still pose a significant health threat for the consumers. The finding of this study warrant the need for educational programs for dairy producers about the risks associated with consumption of certain cheeses manufactured from raw or insufficiently heated milk.