The effect of a novel bovine mastitis trivalent vaccine, containing Staphylococcus aureus capsular polysaccharide type 5 (T5), 8 (T8), and 336 (T336), on lymphocyte subpopulations, antibody production, and neutrophil phagocytosis was evaluated. Twenty pregnant heifers were immunized with either the trivalent alone, trivalent emulsified in Freund's incomplete adjuvant (FICA), trivalent in aluminum hydroxide, or adjuvant only (FICA). Immunization was done 30 d before the expected calving date followed by 2 boosts in a 2-week interval. Compared to FICA, serum antigen-specific immunoglobulin (Ig)G1 and IgG2 were significantly increased in all the vaccinated groups before parturition and sustained until 3 wk postpartum. In comparison with the trivalent alone, formulation with either adjuvant enhanced production of IgG2, but not IgG1. Immune sera, which contained the highest amount of antibodies, slightly increased neutrophil phagocytosis to the 3 serotypes of killed S. aureus, but most of the differences were not significant due to large variation between the cows. The percentage of CD4+ lymphocyte was significantly higher in vaccinated groups than that of FICA 4 wk after the primary immunization. In comparison with FICA, cows inoculated with trivalent vaccine and adjuvants had an increased percentage of CD8+ lymphocytes at 2 time points, 2 wk before and after calving. Our results indicated that the whole cell trivalent vaccine, with or without adjuvants, is able to elicit antibody responses specific to the 3 capsular polysaccharide antigens. The increase of T8-specific IgG2 was more noticeable when the vaccine was emulsified with adjuvants.

Ehrlichia canis is an intracellular pathogen that causes canine monocytic ehrlichiosis. Although the role of antibody responses cannot be discounted, control of this intracellular pathogen is expected to be by cell mediated immune responses. The immune responses in dogs immunized with inactivated E. canis organisms in combination with Quil A were evaluated. Immunization provoked strong humoral and cellular immune responses, which were demonstrable by Western blotting and lymphocyte proliferation assays. By Western blotting antibodies to several immunodominant E. canis proteins were detected in serum from immunized dogs and antibody titres increased after each immunization. The complement of immunogenic proteins recognized by the antisera were similar to those recognized in serum from infected dogs. Upon challenge with live E. canis, rapid anamnestic humoral responses were detected in the serum of immunized dogs and primary antibody responses were detected in the serum from control dogs. Following immunization, a lymphocyte proliferative response (cellular immunity) was detected in peripheral blood mononuclear cells (PBMNs) of immunized dogs upon stimulation with E. canis antigens. These responses were absent from non-immunized control dogs until after infection with live E. canis, when antigen specific-lymphocyte proliferation responses were also detected in the PBMNs of the control dogs. It can be thus concluded that immunization against canine monocytic ehrlichiosis may be feasible. However, the immunization regimen needs to be optimized and a detailed investigation needs to be done to determine if this regimen can prevent development of acute and chronic disease.

In July 2003 a 2-year-old Thoroughbred colt was imported from Harare, Zimbabwe to the Ashburton Training Centre, Pietermaritzburg, South Africa. Five months after importation, the colt presented with clinical signs suggestive of rabies: it was uncoordinated, showed muscle tremors and was biting at itself. Brain tissue was submitted for analysis and the clinical diagnosis was confirmed by the fluorescent antibody test and reverse-transcription polymerase chain reaction (RT-PCR). Phylogenetic analysis of the nucleotide sequence of the cytoplasmic domain of the glycoprotein and the G-L intergenic region of the rabies virus confirmed it to be an infection with a canid rabies virus, originating from an area in Zimbabwe endemic for the domestic dog (Canis familiaris) and side-striped jackal (Canis adustus) rabies.

Five species of ixodid ticks were found in a cross-sectional survey in which 200 sheep were examined for ticks in River Nile Province, Sudan. Hyalomma anatolicum anatolicum was the predominant species (73.6 %), whereas ticks belonging to the Rhipicephalus sanguineus group (14.7 %), Rhipicephalus evertsi evertsi (9.1 %), Rhipicephalus simus (2 %) and Hyalomma dromedarii (0.5 %) were also found. The mean tick load was 11.2 per animal. In a subsequent longitudinal survey ticks were collected on a monthly basis from eight sentinel sheep that were introduced into the area. It was found that H. a. anatolicum almost disappeared during the hot period between April and August, whereas it's highest numbers were present in winter between November and February. It is concluded that there is only one generation of H. a. anatolicum per year, which may explain the yearround appearance of clinical cases of malignant ovine theileriosis indicating endemic instability of this disease in River Nile Province.

Merino sheep in Thornveld, Dorper sheep and Angora goats in inland Valley Bushveld, Angora goats and Boer goats in Valley Bushveld on the coastal plateau, and springbok, Antidorcas marsupialis, and black wildebeest, Connochaetes gnou, in Karroid Mountainveld, all in the Eastern Cape Province, were examined for the larvae of nasal bot flies. The sheep and goats were infested with the larvae of Oestrus ovis, and Dorper sheep and Boer goats harboured more larvae than Angora goats on the same farms. Most infestation was present from November to May in Merino sheep in Thornveld, from February to June in Dorper sheep in inland Valley Bushveld, and from May to September in Angora and Boer goats in Valley Bushveld on the coastal plateau. These patterns of seasonality appeared to be regulated by the severity of the summer temperatures at the various localities. The springbok were infested with the larvae of Rhinoestrus antidorcitis, most of which seemed to mature from June to August. All larval sages of Oestrus variolosus and Gedoelstia hässleri were present in the black wildebeest, and large numbers of 1st instar larvae of G. hässleri appeared to accumulate on the dura of the wildebeest from June to August.

Samples from medial retropharyngeal, superficial cervical and deep femoral lymph nodes of four camels were fixed in neutral buffered formalin and prepared for light and electron microscopic examination. The camel lymph nodes were formed of stroma and parenchyma. A dense collagenous capsule and trabeculae beside fine reticular framework represented the stroma. The parenchyma was formed of follicular and non-follicular forms of lymphoreticular tissue. The lymphoid follicles were mainly secondary in nature formed of germinal center and outer corona. Afferent and efferent lymph vessels were noticed at the same area of the capsule. Capsular, subcapsular, trabecular, peritrabecular and parenchymal lymph sinuses were noticed in camel lymph nodes.

Fifteen outbreaks with clinical picture and post- mortem lesions similar to that of rabbit haemorrhagic viral disease (RHVD) were investigated in vaccinated flocks during the period between February and July 2005 at Kafr El-Sheikh Governorate. Twelve representative liver homogenate were positive in haemagglutination test (HA) using human type (O) washed RBCs, with titer more than 1/160. Detection of virus particles by electron microscopy, histopathological findings as well as pathogenicity test , confirmed that the outbreaks were RHVD. The possible role of field rats for the transmission and spread of RHVD among rabbitaries was studied. Cross reactivity and cross protection tests were conducted. These tests proved that the newly emerged RHVD isolates were not closely related to classical local vaccinal strain of RHVD and may be a variant strain.

During summer 2004, an outbreak of bovine ephemeral fever (BEF) had been spread among cattle as well as buffaloes in Egypt. The most striking clinical signs in cattle were fever of short duration, depression, stiffness, lameness and sometime recumbency. Young calves, unfattened bulls and dry, lean non-pregnant cows showed only mild signs while fattened calves, mature heavy bulls and high-producing dairy cows and cows at the late stages of pregnancy were severely affected and signs persisted longer. Deaths and other complications accompanied the disease such as subcutaneous emphysema was not recorded in these outbreaks. In buffaloes, the clinical signs were mild and less severe compared with that of cattle. Serological examination of paired serum samples collected from the diseased animals using serum neutralization test revealed rising of the neutralizing antibody titers for BEF virus after 3 weeks from the onset of clinical signs. Blood picture and biochemical analysis of sera of 6 diseased animals, showed anemia represented by significant decrease in RBCS, PCV% and Hb content. The leukogram showed neutrophihia and lymphopenia with normal leukocytic count. There was rise in plasma fibrinogen with drop in calcium and phosphorus values. All of these parameters were more or less improved three weeks post-recovery. Good nursing care with early treatment with non-steroid anti-inflammatory drug (Phenylbutazone) or administration of calcium borogluconate of lame or recumbent animals lead to rapid and prompt recovery.

In this study we evaluated the validity of well-known human electrocardiographic markers of myocardial pathology in Dorper sheep. These markers include: the duration of the QRS complex of premature ventricular complexes (PVCs), the presence of notching of the QRS complex of PVCs and change of the ST-segment of PVCs. It was shown that these three electrocardiographic phenomena correlate with myocardial pathology in the hearts of Dorper sheep. We also describe a new electrocardiographic indicator of myocardial pathology, namely an increase in the frequency of cardiac memory T waves as a new electrocardiographic surrogate for myocardial pathology in the hearts of Dorper sheep.

A wild strain of Eimeria tenella was isolated and utilized for immunization studies. Its optimal sporulation was attained at room temperature 24-25 °C after 24-48 h. Two groups of chicks were immunized by dosing a graded dose of five oocysts/chick/day for 6 days followed by 50 oocysts/chick/day for 7 days. A third group was not immunized and served as a negative control. Immunized chicks gained mass at the same rate as unimmunized ones, but when challenged with 200 000 oocysts/chick, mass gains declined in the unimmunized group. The growth rate of immunized chicks was not affected by challenge (P > 0.05). Upon challenge, unimmunized chicks produced significantly more oocysts than immunized chicks (P < 0.005). Immunized chicks withstood a challenged with 200 000 oocysts/chick without developing any clinical signs whereas the unimmunized chicks developed typical clinical signs of coccidiosis. Unimmunized chicks had significantly more severe lesions in the caecum than any other group (P > 0.005) and also produced significantly more oocysts than any other group (P > 0.005).