A cross-sectional study to determine the prevalence of bovine cysticercosis and hydatidosis was conducted from October 2007 to March 2008 in cattle slaughtered at the Jimma municipal abattoir. Cyst distribution and viability of bovine cysticercosis and hydatidosis were also determined. A total of 512 carcasses were inspected of which 15 (2.93%) and 161 (31.44%) were infected with Taenia saginata metacestodes and hydatid cysts, respectively. From a total of 109 cysticerci collected from infected carcasses, 47 (43.12 %) were viable. The anatomical distribution of the cysticerci was, shoulder muscle (39.5°%), heart (33.9 %), neck muscle (13.8°%), tongue (10.1°%), masseter muscles (1.8°%) and diaphragm (0.9°%). Of the 1171 hydatid cysts collected 223 (19.0°%) were fertile, 505 (43.1 °%) sterile, 49 (29.8 °%) calcified and 94 (8.0 °%) contained pus. A greater proportion of fertile cysts were found in the lungs than in other organs. It was concluded that these zoonotic cestodes deserve due attention to safeguard public health, and that further studies are needed on genotyping, epidemiology and public health importance of Echinococcus granulosus in the study area.

Although a number of brief, fragmented descriptions have been provided on the gross morphology of the ratite tongue, very few studies have documented the histological structure of this organ. This paper presents the first definitive histological description of the emu tongue and reviews, consolidates and compares the scattered information on the histology of the ratite tongue available in the literature. Five tongues were removed from heads obtained from birds at slaughter and fixed in 10 % neutral buffered formalin. Appropriate longitudinal and transverse segments were removed, routinely processed for light microscopy, and sections examined after staining with H & E and PAS. The entire tongue (body and root) is invested by a non-keratinized stratified squamous epithelium. The supporting connective tissue of the tongue dorsum displays only large, simple branched tubular mucus-secreting glands, whereas the caudal tongue body ventrum and tongue root, in addition to these glands, also exhibits small, simple tubular mucus-secreting glands. Herbst corpuscles are associated with the large, simple branched glands. Lymphoid tissue is restricted to the tongue ventrum and is particularly obvious at the junction of the ventral tongue body and frenulum where a large aggregation of diffuse lymphoid tissue, with nodular tissue proximally, was consistently observed. A structure resembling a taste bud was located in the epithelium on the caudal extremity of the tongue root of one bird. This is the first reported observation of taste buds in ratites. Forming the core of the tongue body is the cartilaginous paraglossum lying dorsal to the partially ossified rostral projection of the basihyale. The histological features of the emu tongue are generally similar to those described for the greater rhea and ostrich, except that taste buds were not identified in these species. The results would suggest that the emu tongue functions as a sensory organ, both for taste and touch (by virtue of taste receptors and Herbst corpuscles, respectively), as well as fulfilling an immunological function.

A longitudinal study of animal and human rabies covering 18 years from 1989 to 2006 was retrospectively conducted in order to highlight the epidemiological features and trends of the disease in Botswana. Over the 18-year period, a total of 4 306 brain specimens collected from various species of animals including human beings with clinical signs consistent with rabies were submitted to the National Veterinary Laboratory in Gaborone for confirmatory diagnosis. Of the samples submitted, 2 419 cases were found to be positive for lyssavirus antigen; this presents an overall prevalence rate of 56.18 ± 1.48 %. About 85.7 % (2 074/2 419) of the cases were from domestic animals, 14.2 % (343/2 419) cases were from wild animals and two cases (0.1 %) were from human beings. During the first half of the study (1989-1997) the prevalence rate of the disease was estimated at 62.79 ± 1.85 % (1 645/2 620 positive) whereas during the second half (1998-2006) it was estimated at 45.91 ± 2.38 % (774/1 686 positive) and the difference between the two estimates was statistically, highly significant (&#916; % = 16.88, SE (95), diff % = 3.015, SD = 5.599; P< 0.001). Ruminant rabies accounted for 79.99 % (50.92 % bovine, 28.40 % caprine and 0.67 % ovine) whereas canine (domestic dog) and feline (domestic cat) accounted for 16.01 and 0.87 %, respectively. Equine rabies accounted for 3.13 % with 1.35 and 1.78 %, respectively, for horses and donkeys. Jackal rabies accounted for more than 60 % of the total cases in wild animals. These findings are discussed in relation to the previous epidemiological situation of the disease (1979-1988), its socio-economic impact, monitoring and control in Botswana.

Cryptosporidium parvum is the most frequent parasitic agent that causes diarrhoea in AIDS patients in Thailand. Cryptosporidiosis outbreaks in humans may be attributed to contamination of their drinking water from infected dairy pastures. A 23-kDa glycoprotein of C. parvum (CpP23) is a sporozoite surface protein that is geographically conserved among C. parvum isolates. This glycoprotein is a potentially useful candidate antigen for the diagnosis of cryptosporidiosis by enzyme-linked immunosorbent assay. Therefore, we investigated the seroprevalence of C. parvum infection in dairy cows in northern Thailand using an ELISA based on recombinant CpP23 antigen. Sera were randomly collected from 642 dairy cows of 42 small-holder farmers, which had the top three highest number of the dairy cows' population in Northern Thailand, that included Chiang Mai, Chiang Rai and Lumpang provinces. The overall seroprevalence of the infection was 4.4 %, and the seropositive rates for the three provinces were 3.3 % in Chiang Mai, 5.1 % in Chiang Rai and 3 % in Lumpang. These results suggest that cattle could play a role in zoonotic cryptosporidiosis in Thailand.

In 2007 Nevill, Venter, Meiswinkel & Nevill demonstrated that the pupae of five Culicoides species belonging to the Imicola complex of the subgenus Avaritia could readily be differentiated from one another using various morphological characters. Three of the described species, Culicoides bolitinos Meiswinkel 1989; Culicoides loxodontis Meiswinkel 1992 and Culicoides sp. # 107 (= C. kwagga, Meiswinkel, unpublished thesis 1995), were reared from the dung of large herbivores, which included buffaloes, elephants, white and black rhinoceroses and zebras. However, during that study a further two Avaritia species, neither of which belonged to the Imicola complex, were reared from dung and these are the subject of the present study. For the past 20 years the adults of these two new closely related species have been known as Culicoides sp. # 54 pale form (p.f.) Meiswinkel and Culicoides sp. # 54 dark form (d.f.) Meiswinkel. The taxonomic description and formal naming of the adults of these two species has yet to be done. The present description and comparison of their pupae show that they are two clearly distinct species; that there is no group of morphological characters that can be used to differentiate these two species from the previously described five species of the Imicola complex; and finally that there was no difference between the pupae of C. sp. # 54 d.f. nor C. sp. # 54 p.f. reared from the dung of different host animals.

African swine fever (ASF) is a devastating haemorrhagic fever of pigs that causes up to 100 % mortality, for which there is no vaccine. It is caused by a unique DNA virus that is maintained in an ancient cycle between warthogs and argasid ticks, making it the only known DNA arbovirus. ASF has a high potential for transboundary spread, and has twice been transported from Africa to other continents - Europe and subsequently the Caribbean and Brazil (1957, 1959) and the Caucasus (2007). It is also a devastating constraint for pig production in Africa. Research at Onderstepoort Veterinary Institute has made and is making important contributions to knowledge of this disease, focusing on the cycle in warthogs and tampans and transmission from that cycle to domestic pigs, resistance to its effects in domestic pigs, and the molecular genetic characterisation and epidemiology of the virus.

African horsesickness (AHS) played a major role in the history and development of southern Africa, both in times of peace and of war. Frequent epidemics of AHS resulted in major transportation impediments. The viral (filterable) nature of the aetiological agent was proven in 1900 by Sir John M'Fadyean in London, making it one of the first animal diseases for which this had been demonstrated. Similarly, the cultivation of AHS virus in the brain of mice and its subsequent attenuation were also amongst the first such feats for animal viruses. Interestingly, both milestones followed the initial work of Max Theiler (son of Sir Arnold) with yellow fever virus.

The declining efficacy of acaricide treatment as a means of reducing the prevalence of Theileria parva infections in sub-Saharan Africa has intensified efforts to achieve control through immunization of susceptible cattle. The infection and treatment method of immunization has enjoyed a resurgence with the availability of more effective cold chain facilities, although concerns remain regarding the possibility of vaccine strains spreading in local tick populations. In addition, an in-depth understanding of protective mechanisms deployed by immune cattle and the antigens targeted by them has led to substantial progress in the development of candidate subunit vaccines against both sporozoite and schizont stages of the parasite. The likely success of these vaccines, as well as infection and treatment immunization, will ultimately depend on the extent to which they disturb the endemic status of the parasite. These issues are discussed in the light of recent information on the genotypic diversity of T. parva in the field and the extent to which this is compromised by the immune response.

The present study was performed in order to evaluate the effects of lower than usual industry levels of dietary trace minerals on plasma levels, faecal excretion, performance, mortality and morbidity in growing-finishing pigs in a hot African climate. Group 1 (n =100 pigs) received a diet with common industry levels of trace minerals. Group 2 (n =100 pigs) received reduced dietary trace mineral levels but were fed the same basic diet as Group 1. Mortality, morbidity, pig performance and carcass measurements were evaluated. Two pigs in Group 1 and three pigs in Group 2 died. Thirteen pigs in Group 1 and 27 pigs in Group 2 were medically treated (P < 0.05). Carcass masses, back fat depth, loin depth, and lean percent were not significantly different between the groups. However, the carcasses when evaluated revealed a non-significant higher back fat thickness, lower loin eye area and percentage of fat free lean in barrows compared to gilts within each group. Despite lower initial masses, pigs fed diets containing industry levels of trace minerals were heavier (P < 0.05) and had a higher (P < 0.05) than average daily gains compared to those that received a diet containing lower levels of trace minerals. Faecal zinc excretion was significantly lower (P < 0.05) in pigs fed with lower dietary zinc levels. Copper, manganese and iron excretion were not affected (P > 0.05) by the dietary levels of these trace minerals. Plasma trace mineral concentrations were not affected by the dietary treatment.

This study compares the prevalence of ixodid tick species on cattle and goats in Maputo Province. Adult ticks as well as the nymphs of three species, and only the adults of two species were collected from sets of five cattle at 21 localities throughout the province and compared with those collected from similar sets of goats at the same places. Amblyomma hebraeum adults and / or nymphs were present on cattle and on goats at all 21 localities, and 90 cattle and 22 goats were infested with adult ticks. Rhipicephalus (Boophilus) microplus adults and / or nymphs were collected from cattle at 20 and from goats at 15 localities, and 92 cattle and 34 goats were infested [Chi-square test (×2), P < 0.001]. The total length of several maturing female R. (Boophilus) microplus collected from cattle and goats exceeded 5 mm, indicating that they successfully engorge on both host species. Rhipicephalus appendiculatus adults and / or nymphs were present on cattle at 15 and on goats at 13 localities, but 28 cattle and only one goat were infested with adult ticks (×2, P < 0.001). Adult Rhipicephalus evertsi evertsi were recovered from cattle at 20 and from goats at 17 localities, and 74 cattle and 69 goats were infested. Adult Rhipicephalus simus were collected from cattle at 18 and from goats at 11 localities (Fisher's exact test, P = 0.04), and 60 cattle and 14 goats were infested (×2, P < 0.001). These findings underscore the advisability of including goats in acaricide application programmes designed for the control of tick-borne diseases in cattle at the same locality.