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The comparative prevalence of five ixodid tick species infesting cattle and goats in Maputo Province, Mozambique Full text
2009
De Matos, C.(Instituto de Investigação Agrária de Mozambique ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Sitoe, C.(Instituto de Investigação Agrária de Mozambique) | Neves, L.(Universidade Eduardo Mondlane Faculdade de Veterinária) | Nöthling, J.O.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Horak, I.G.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,University of the Free State Department of Zoology and Entomology)
Ecological parameters of Lamproglena hoi (Copepoda: Lernaeidae) infection on the Bushveld smallscale yellowfish, Labeobarbus polylepis (Boulenger, 1907) Full text
2009
Austin, A.(University of Johannesburg Department of Zoology) | Avenat-Oldewage, A.(University of Johannesburg Department of Zoology)
This study describes the distribution and aspects of the ecology of Lamproglena hoi. Bushveld small-scale yellowfish, Labeobarbus polylepis (Boulenger, 1907) were collected during June 2006 from the Phongolo and Assegaai rivers, March 2005 and October 2006 from the Elands River, and January 2007 and June 2008 from the Komati River in Mpumalanga, South Africa and examined for the presence of parasites. Lamproglena hoi specimens were collected from the gill filaments of the host. Specimens were fixed with warm AFA (alcohol-formaldehyde-acetic acid) and preserved in 70 % ethanol. The identification of parasites took place in the laboratories of the University of Johannesburg. Twenty-five copepods (prevalence 21 %, mean intensity = 4.17, abundance = 0.86) were collected on 29 fish in the Phongolo River and 46 copepods (prevalence 40 %, mean intensity = 3.83, abundance = 1.53) were collected on 30 fish in the Assegaai River. One hundred and sixty eight copepods (prevalence 52 %, mean intensity = 12.92, abundance = 6.72) were collected on 25 fish in 2005, and 527 copepods (prevalence 95 %, mean intensity = 27.74, abundance = 26.35) were collected on 20 fish in the Elands River. One hundred and sixteen copepods (prevalence 75 %, mean intensity = 7.73, abundance = 5.80) were collected on 20 fish in 2007, and 273 copepods (prevalence 63 %, mean intensity = 16.06, abundance = 10.11) were collected on 27 fish in 2008 in the Komati River. Labeobarbus polylepis from these four rivers was found to have a relatively high L. hoi infection. Inseminated L. hoi females (immature) attach to the host in winter and their ovaries become conspicuous (mature). In spring fertilized eggs are stored in egg sacs hanging from the body (gravid), indicating that fertilized eggs start to hatch in spring and continued hatching into summer. Parasites prefer the median part of the second gill arch for attachment. No correlation exists between the number of parasites recorded on the gills and the sizes (total lengths) of yellowfish sampled.
Show more [+] Less [-]Species composition and geographic distribution of ticks infesting cattle, goats and dogs in a temperate and in a subtropical region of south-east Africa Full text
2009
Horak, I.G.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,University of the Free State Department of Zoology and Entomology) | Nyangiwe, N.(Döhne Agricultural Development Institute ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | De Matos, C.(Instituto de Investigação Agrária de Mozambique ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Neves, L.(Universidade Eduardo Mondlane Faculdade de Veterinária)
The species and distribution of ticks infesting cattle, goats and dogs in the eastern region of the Eastern Cape Province, South Africa and Maputo Province, Mozambique were determined from collections made from these animals at 72 localities in the former region and 30 in the latter. Eleven ixodid and one argasid species were recovered in the Eastern Cape Province and 15 ixodid species in Maputo Province. The most common ticks infesting cattle and goats in both provinces were Amblyomma hebraeum, Rhipicephalus (Boophilus) microplus, Rhipicephalus appendiculatus and Rhipicephalus evertsi evertsi. The dominant species on dogs were Haemaphysalis elliptica and Rhipicephalus simus. The geographic distributions of the major species and some of the minor species in both regions were plotted. The partial or complete displacement of the indigenous tick Rhipicephalus (Boophilus) decoloratus by the introduced species R. (B.) microplus was a major feature of both surveys.
Show more [+] Less [-]Description and comparison of the pupae of a further two Culicoides (Avaritia) species from the dung of large herbivores in South Africa (Diptera: Ceratopogonidae) Full text
2009
Nevill, Hilda | Nevill, E.M. | Venter, G.J.(ARC-Onderstepoort Veterinary Institute)
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.
Show more [+] Less [-]Detection of natural Trypanosoma vivax infections in pigs with microhaematocrit centrifugation and amplification of ITS1 rDNA Full text
2009
Biryomumaisho, S.(Makerere University Department of Veterinary Medicine) | Melville, S.E.(University of Cambridge Department of Pathology) | Katunguka-Rwakishaya, E.(Makerere University Department of Veterinary Medicine) | Lubega, G.W.(Makerere University Department of Veterinary Parasitology and Microbiology)
Different species of trypanosomes may infect their mammalian hosts both singly or in combination. This study was undertaken to determine the trypanosome species that may be afflicting pigs in Uganda. Blood was collected from pigs of all ages and sexes from two districts, Kasese in Western and Jinja in Central Uganda. Of the 133 pig blood samples from Kasese that were tested for trypanosomes using the microhaematocrit centrifugation technique (MHCT), none was found to be infected. However, of the 253 pigs from Jinja district, nine were infected with trypanosomes of which three had T. vivax as determined by MHCT. However, application of the ITS1 rDNA PCR test revealed that eight pigs had T. vivax in mixed infections and one pig had T. vivax monolithic infection. These observations show that under certain circumstances, pigs may be important reservoirs for, as well as hosts to, T. vivax, contrary to earlier reports.
Show more [+] Less [-]The effects of low levels of dietary trace minerals on the plasma levels, faecal excretion, health and performance of pigs in a hot African climate Full text
2009
Boma, M.H. | Bilkei, G.
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.
Show more [+] Less [-]Blood platelet counts, morphology and morphometry in lions, Panthera leo Full text
2009
du Plessis, L.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology)
Due to logistical problems in obtaining sufficient blood samples from apparently healthy animals in the wild in order to establish normal haematological reference values, only limited information regarding the blood platelet count and morphology of free-living lions (Panthera leo) is available. This study provides information on platelet counts and describes their morphology with particular reference to size in two normal, healthy and free-ranging lion populations. Blood samples were collected from a total of 16 lions. Platelet counts, determined manually, ranged between 218 and 358 x 10(9)/l. Light microscopy showed mostly activated platelets of various sizes with prominent granules. At the ultrastructural level the platelets revealed typical mammalian platelet morphology. However, morphometric analysis revealed a significant difference (P < 0.001) in platelet size between the two groups of animals. Basic haematological information obtained in this study may be helpful in future comparative studies between animals of the same species as well as in other felids.
Show more [+] Less [-]Prevalence of bovine cysticercosis and hydatidosis in Jimma municipal abattoir, South West Ethiopia Full text
2009
Tolosa, T.(Jimma University College of Agriculture and Veterinary Medicine School of Veterinary Medicine) | Tigre, W.(Jimma University College of Agriculture and Veterinary Medicine School of Veterinary Medicine) | Teka, G.(Jimma University College of Agriculture and Veterinary Medicine School of Veterinary Medicine) | Dorny, P.(Ghent University Faculty of Veterinary Medicine Laboratory of Parasitology,Institute of Tropical Medicine Department of Animal Health)
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.
Show more [+] Less [-]Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features Full text
2009
Crole, M.R.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology) | Soley, J.T.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology)
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.
Show more [+] Less [-]Comparative histopathology of the lymph nodes, spleen, liver and kidney in experimental ovine trypanosomosis Full text
2009
Omotainse, S.O.(University of Agriculture College of Veterinary Medicine Department of Veterinary Pathology) | Anosa, V.O.(University of Ibadan Faculty of Veterinary Medicine Department of Veterinary Pathology)
The infection of Yankassa rams with three important trypanosome species affecting livestock, namely, Trypanosoma congolense, T. vivaxand T. bruceiproduced both acute and chronic fatal conditions. Chronic infections were induced in the three infections by the application of subcurative doses of diaminazene aceturate (Berenil®). Pathological changes in the infected animals included splenomegaly and hepatomegaly which were more pronounced in acute than in chronic T. congolense infection. However, these changes were more severe in chronic than in acute T. vivax infection. While splenomegaly was more pronounced in chronic T. brucei infection than in acute, hepatomegaly and lymphadenopathy were more severe in acute than in the chronic condition. The increases in size of the spleen, lymph nodes and liver were associated with congestion, increases in cell density related to increased immunological reactions in the spleen and lymph nodes as well as increase in numbers, size and activity of the phagocytic cells in these organs.
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