It is suggested that Haemophilus paragallinarum requires at least three haemagglutinins for adhesionduring infection. This paper reports the partial purification and characterization of the HA-L haemagglutininfrom H. paragallinarum strain 46-C3, a heat sensitive, trypsin sensitive haemagglutinin that hasbeen shown to be the serovar specific haemagglutinin in this organism. Using the pI and molecularmass obtained, it was shown that this protein shares similarities with other types of adhesins found in Gram-negative bacteria. The haemagglutination assay conditions were optimized at pH 7.5 at 37 °C. It was also shown that activity is enhanced by the addition of Ca2+ and Mn2+ ions.

The present study investigated the distribution of nerves in the ovary of the emu. The neuronal markers, protein gene product 9.5, neurofilament protein and neuron specific enolase demonstrated the constituents of the extrinsic and intrinsic ovarian neural systems. The extrinsic neural system was composed of ganglia in the ovarian stalk, as well as nerve bundles, which were distributed throughout the ovary. Isolated neuronal cell bodies, in the medulla and cortex, formed the intrinsic neural system. An interesting finding of the study was the presence of nerve bundles, circumscribed by lymphocytes, in the ovarian stalk. The findings of the study indicate that the distribution of nerve fibres and neuronal cell bodies in the emu ovary is similar, but not identical to that of the domestic fowl and ostrich.

Experimental Trichinella zimbabwensis infections were established in three baboons (Papios p.)and four vervet monkeys (Cercopithecuase thiops) and the clinical-pathological manifestations assessed. The infected animals showed clinical signs ranging from fever, diarrhoea, periorbitaol edema and muscular pain in varying degrees. One baboon became blind due to the infection. Levels of creatinine phosphokinase and lactated ehydrogenase increased to reach a peak on Day 42 post-infection(pi)for both baboons and monkeys. Blood parameters such as packed cell volume, levels of red blood cells and white blood cells did not change significantly from the normal ranges except for the levels of eosinophils which peaked above the normal ranges at Day 28 and 56 pi in baboons and at Day 56 pi in monkeys.

The prevalence and geographic distribution of the fowl tampan, Argas walkerae Kaiser & Hoogstraal, 1969 was determined in the eastern region of the Eastern Cape Province, South Africa by inspecting two fowl houses in the vicinity of each of 72 randomly selected communal cattle dip-tanks. Tampans were collected from 102 (70.8 %) of the 144 fowl houses in the neighbourhood of 57 (79.2 %) of the 72 selected dip-tanks, and the localities of the collections were mapped. Argas walkerae was present in fowl houses from the warm coastal regions of the Indian Ocean in the south to the cold and mountainous Drakensberg in the north-east of the Province. Taking into account the probable sensitivity of the sampling method, it is estimated that A. walkerae is likely to be present in fowl houses belonging to between 74 and 84 % of communities making use of cattle dip-tanks in the eastern region of the Eastern Cape Province, and that when it is present, between 64 and 75 % of fowl houses will be infested. The geographic distribution of A. walkerae seemed to be more strongly associated with the presence of fowls and fowl houses containing raw or processed wood in their structure than with climate.

Spirocerca lupi (Spirurida: Spirocercidae) is a cosmopolitan parasite, principally of domestic dogs and dung beetles are its main intermediate hosts. In South Africa there has recently been growing concern over the upsurge of reported cases of clinical spirocercosis in dogs, while little is known or understood about the dynamics of the host-parasite associations between dung beetles and this nematode. We determined and compared the prevalence of infection in dung beetles between rural, urban and periurban areas of Tshwane (Pretoria) Metropole. Dung beetles were sampled during April and October 2006, at various localities in each of these areas. Localities were selected on the basis of being focal areas of high infection with S. lupi in dogs. Pig, dog and cow dung-baited pitfall traps were used for sampling the beetles. Trap contents were collected 48 h after the traps had been set and only dung beetles were collected from the traps. In total, 453 specimens belonging to 18 species were collected from 63 pitfall traps in all three areas. The numbers of species that were collected varied among the three areas. Dung beetles, irrespective of species (18) and numbers (447), predominantly preferred pig dung. The prevalence of dung beetles infected with the larvae of S. lupi varied considerably in the three areas. In the urban area 13.5 % of the dung beetles dissected were infected, while the prevalence of S. lupi in dung beetles in the rural area was 2.3 %. All the dung beetles that were infected with this nematode showed a preference for omnivore (pig and dog) dung.

Serum samples from 237 randomized rabbits from the five ecological zones of Nigeria, i.e. Northwest (NW), Northeast (NE), Southeast (SE), Southwest (SW) and Northcentral (NC), were evaluated for the presence of antibodies to Encephalitozoon cuniculi by the indirect immunofluorescent antibodies test. A titre of 10 or more was taken as positive. Thirty-nine (16.5 %) of the 237 samples were positive with 11, 10, 8, 6 and 4 seropositive rabbits occurring in the NW, NE, SE, SW and NC zones of Nigeria, respectively. Age, sex, live mass and access to grass as a feed supplement were not statistically (P > 0.05) associated with seropositivity, but cage type (single-versus multi-rabbit type), contact with free-range rats and previous illness were strongly (P < 0.05) associated with it. The practice of selling unscreened and untreated 5 to 10-week-old weaners to prospective buyers as foundation stock, use of multi-rabbit communal cages, occasional release of rabbits in runs and contact with free-range house rats should be discouraged. Regular prophylactic and curative treatments, occasional serological screening to remove carriers, and the practice of a high level of hygiene in rabbit colonies are effective control measures.

The macroscopic features of the venous drainage of the reproductive system of the male ostrich were studied in six pre-pubertal and three sexually mature and active birds. Each testis was drained by one to four testicular veins. The right testicular veins drained the right testis and epididymis and its appendix to the caudal vena cava and to the right common iliac vein, whereas the left testicular veins drained the left testis and epididymis and its appendix exclusively to the left common iliac vein. A number of variations in the drainage pattern based on the point of entry and number of testicular veins were observed. The cranial aspect of the testis was also linked to the caudal vena cava or common iliac vein via the adrenal veins. The cranial, middle and caudal segments of the ductus deferens (and ureter) were drained by the cranial, middle and caudal ureterodeferential veins respectively, to the caudal testicular veins, the caudal renal veins and pudendal / caudal part of the internal iliac veins. In some specimens, the caudal ureterodeferential veins also drained into the caudal mesenteric vein. The surface of the phallus was drained by tributaries of the pudendal vein. The basic pattern of venous drainage of the reproductive organs of the male ostrich was generally similar to that described for the domestic fowl. However, important differences, including the partial fusion of the caudal renal veins, drainage of the cranial aspect of the testes via the adrenal veins, drainage of the caudal ureterodeferential veins into the caudal mesenteric vein and the presence of veins draining the surface of the phallus, were observed. Although significant, these differences may simply reflect variations in the normal pattern of venous drainage of the reproductive tract of birds which could be verified by studying more specimens and more species.

Four stocks of Ehrlichiar uminantium (Welgevonden, Ball3, Nonile and Blaauwkrans), the causative agent of heartwater in domestic ruminants, were isolated into lxodes capularis (lDE8) tick cells using the leukocyte fraction of the blood of infected sheep. Organisms of two of the E. ruminantrum stocks (Welgevonden and Blaauwkrans) propagated in IDEB cells were also successfully used to infect bovine endothelial cells. All stocks were successfully propagated in IDEB cells using Dulbecco's modified Eagle's medium nutrient mixture Ham F-12c ontaining 10% foetal bovine serum (FBS). The technique should be included in any attempt to isolate uncharacterized E. ruminantium stocks.

Lactose in normal saline was administered intravenously to a group of Zebu cattle infected with Trypanosoma vivax to determine the bloodplasma kinetics at onset of an experimental infection and its ability to protect tissues against damage as part of preliminary studies to determine its suitability for use in the treatment of trypanosomosis. Significant (P <0.01) higher lactose concentrations were observed in the T. vivax-intecled bulls at 30 min and 1h (P< 0.05) post-infectio (p.i.) and by 4 h p.i. the plasma lactose remained above the level prior to infusion, after which it fell slightly below the preinfusion level in the uninfected group. Calculated pharmacokinetic parameters revealed delayed excretion of lactose in the T. vivax-intected group soon after infection. The total body clearance (C/B )was significantly (P < 0.05) reduced. The biological half-life (t1/2), elimination rate constant (kel) and apparent volume of distribution (Vd) were relatively decreased (P > 0.05) as a result of the T. vivax infection. Retention of lactose in the plasma was attributed to decreased plasma clearance l.t is suggested that the presence of trypanosomes in circulation rather than organic lesions could have been responsible for the delay observed in the excretion of lactose. At 12 weeks p.i., when the experiment was terminated, the group infected and given lactose infusion (despiteh igherp arasitaemia) had no gross or histopathological lesions in the brain, spleen, lymphnodes, heart, kidneys, liver and testes. However, the group infected but not infused with lactose were emaciated, had pale mucosae, watery blood, general muscular atrophy, serous atrophy of coronary fat and other adiposet issue, hepatomegalys, plenomegalys, wollen and oedematous lymph nodes, all of which are suggestive of trypanosomosis. Histopathological lesions included arrowing of Bowman's space and hypercellularity of glomerular tufts in the kidneys with the mean glomerula truft nucleairn dices (GTNs) in the group significantly higher (P <0.01)than the mean GTNs of the lactoseinfused and control bulls. Degenerative changes occurred in the myocardium, spleen, testes and epididymides. The tesicular and epididymal lesions are indicative of male reproductive dysfunction.

The ability of intravenously administered lactose in normal saline to prevent a decline in packed cell volume (PCV) during experimental trypanosomosis was studied in Zebu cattle. During the lactose infusion period, the PCV was stable up to Day 5 post-infection (p.i.) in a lactose-infused group, compared to that in an uninfused group in which the PCV dropped significantly (P < 0.05) as shown by the values of cumulative percentage change. Furthermore the mean rate of change in PCV was significantly (P < 0.05) higher in the uninfused group relative to the lactose-infused group during the same period. While the PCV fell markedly in the lactose-infused group a day after lactose infusion was stopped (Day 13 p.i.), subsequent PCV values were significantly (P < 0.05) higher compared to those in the uninfused group, up to the end of experiment on Day 17 p.i. However the mean rates of change in PCV did not vary significantly (P > 0.05) between the groups during the period in which lactose infusion was stopped. The mean levels of parasitaemic waves and parasitaemia were higher, more prolonged and more frequent in the lactose-infused group. It was inferred that the lactose was able to prevent an early onset of anaemia in the Trypanosoma vivax-infected Zebu cattle.