In this study field application of RB51 vaccine combined with the policy of test and slaughter as well as application of hygienic measures for control of bovine brucellosis were carried out and evaluated in a dairy herd of cattle for two years. Serological examination of 1280 cattle using tube agglutination, buffered acidified plate antigen, Rose Bengal plate antigen and Rivanol tests revealed 240 (18.75%) positive animals with a previous history of abortion of 12 cows. Brucella melitensis biovar 3 could be isolated from tissue specimens of slaughtered cows. Animals that tested negative in the first examination were vaccinated with RB 51 vaccine with periodical examination every three weeks and slaughtering of positive cases. New positive cows continued to develop up to the 5th examination then three successive sero-negative tests were obtained with release of the farm from quarantine. Examination of animals 6,12,18 and 24 months post release of quarantine revealed 2, 3, 0 and one positive cases respectively the matter which clarified that the control of the outbreak using RB51 vaccine associated with policy of test and slaughter and application of hygienic measures showed some limitations.

A total of 980 camels were employed in this study for evaluation of some diagnostic procedures used for diagnosis of camel trypanosomiasis. Clinical examination revealed that 180 (18.37%) camels showed sings of illness including, loss of body weight, anemia, abortion, decrease of animal production and edema in some parts of the body. Parasitological examination of camel’s blood smears revealed the presence of Trypanosoma evansi in 57 (5.82%) camels. ELISA detected 99 (63.06%) positive cases while suratex test identified 80 (50.96%) positive cases. Results of mice inoculation test for detection of Trypanosoma evansi among camels showed that 69 (43.95%) camels were positive. The present study clarified that suratex test was 100% sensitive for diagnosis of trypanosomiasis followed by ELISA (98.55%).

Serum samples from 20 out of 180 (11.1 %) apparently healthy Nigerian indigenous chickens were negative for antibodies against chicken anaemia virus using the enzyme-linked immunosorbent assay (ELISA). Of the 160 positive sera (88.9 %), 12 (7.5 %) had titres ranging from 1 500-3 000, 46 (28.8 %) had titres from 3 000-5 000 while 102 (63.8 %) had titres between 5 000-11 000. The overall mean titre value was 5 845 + 2 402. This appears to be evidence of a natural outbreak of the infection since the chickens had no history of vaccination against any poultry disease.

In the present study, the humoral immune response developed following vaccination with the live-attenuated (Smithburn) Rift Valley fever (RVF) vaccine in sheep, goats, cattle, buffaloes and camels was investigated. Results showed that, serum neutralizing antibody titers of RVF virus started to appear in the sera of all vaccinated animals with live-attenuated Rift valley fever vaccine after the first week post-vaccination and reached its peak after the third month of vaccination. It persisted to be higher than the acceptable limit of protection (>40) in the sera of sheep and goats in more than 6 months post-vaccination while it declined in the sera of cattle, buffaloes and camels to become lower than the acceptable limit of protection (<40) after the sixth month post-vaccination. On the other hand, the serum neutralizing antibody titers remained negative in the sera of non-vaccinated (control) animals throughout the study. It could be concluded that, the neutralizing antibodies following vaccination of cattle, buffaloes and camels with live attenuated RVF (Smithburn) vaccine was low and of a short duration compared with those in sheep and goats. Hence, it is important to prepare a new vaccine which is safe and gives a high immune response for long period in cattle, buffaloes and camels instead of live attenuated (Smithburn) RVF vaccine to protect these animals species against this disease.

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 present study was designed in a trial to use serum replacement instead of the newborn calf serum in propagation of BHK-21 cell cultures with subsequent reducing the cost of foot and mouth disease (FMD) vaccine production. Two batches of BHK-21 cell culture were prepared where the medium of the first batch was supplemented with newborn calf serum while the medium of the second batch was supplemented with serum replacement. FMD virus was propagated 7 passages using BHK-21 cell culture. Both virus titration and complement fixation titer (CF) revealed that propagation of FMD virus in cell cultures supplemented with newborn calf serum yields a titre higher than that in case of cells supplemented with serum replacement. Also two batches of FMD inactivated vaccine were prepared from the virus propagated in the two-mentioned cell culture batches. Two groups of susceptible calves were vaccinated with these vaccines. Both of virus neutralization test (VNT) and enzyme linked immunosorbent assay (ELISA) revealed that higher antibody levels were induced in calves vaccinated with the vaccine prepared from cells supplemented with calf serum than those vaccinated with vaccine prepared from cells grown with serum replacement. BHK-21 cell culture supplement with newborn calf serum is most susceptible for FMD virus propagation yielding higher titer of the virus. Moreover, the growth pattern of the used cell culture was much better when the newborn calf serum was used.

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.

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.

Theileria parva-naïve Friesian (Bos taurus), Boran (Bos indicus) and Maasai Zebu steers (B. indicus) were infected with a T. parva sporozoite stabilate dose which had previously been shown to induce an estimated 50 % mortality rate in Boran cattle. All the cattle developed patent infections with no significant differences in the length of the prepatent period to development of macroschizonts (P > 0.05) between the three groups. Clinical theileriosis occurred in all eight the Friesians (100 %), five out of nine Borans (55.6 %) and two out of five Zebus (40 %). Three of the Friesians (37.5 %), and two of the Borans (22.2 %) died of theileriosis. The different cattle types were equally susceptible to the infective dose used as indicated by the length of the prepatent periods, but there was a marked difference in their development of clinical theileriosis. The gradation in resistance to disease confirms the findings of earlier less critical studies and identifies these cattle breeds as suitable for investigations into the mechanisms of resistance to theileriosis.