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Canine babesiosis : tick-borne diseases Texto completo
2009
Schoeman, J.P.
Canine babesiosis : tick-borne diseases Texto completo
2009
Schoeman, J.P.
Babesiosis is a tick-borne disease affecting humans and many domestic and wild animals. Domestic animals showing appreciable morbidity and mortality include dogs, cats, cattle and horses. Both canine and feline babesiosis are diseases characterised by haemolytic anaemia, icterus and haemoglobinuria. Canine babesiosis can range from chronic or subclinical to peracute and fatal, depending on the virulence of the species and the susceptibility of the host. This paper deals with canine babesiosis with specific reference to pathogenesis, clinical findings, complications, diagnosis and treatment, as well as newly identified prognostic factors in Babesia rossi babesiosis.
Mostrar más [+] Menos [-]Canine babesiosis : tick-borne diseases Texto completo
2009
J.P. Schoeman
Babesiosis is a tick-borne disease affecting humans and many domestic and wild animals. Domestic animals showing appreciable morbidity and mortality include dogs, cats, cattle and horses. Both canine and feline babesiosis are diseases characterised by haemolytic anaemia, icterus and haemoglobinuria. Canine babesiosis can range from chronic or subclinical to peracute and fatal, depending on the virulence of the species and the susceptibility of the host. This paper deals with canine babesiosis with specific reference to pathogenesis, clinical findings, complications, diagnosis and treatment, as well as newly identified prognostic factors in Babesia rossi babesiosis.
Mostrar más [+] Menos [-]Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features Texto completo
2009
Crole, M.R. | Soley, J.T.
Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features Texto completo
2009
Crole, M.R. | Soley, J.T.
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 mucussecreting 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.
Mostrar más [+] Menos [-]Morphology of the tongue of the emu (<i>Dromaius novaehollandiae</i>). II. Histological features Texto completo
2009
M.R. Crole | J.T. Soley
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 mucussecreting 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.
Mostrar más [+] Menos [-]Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texto completo
2009
Mitema, E.S.
Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texto completo
2009
Mitema, E.S.
Drugs, hormones and pesticides are chemical compounds used for alleviation of various diseases in animals. There are many classes of drugs which have been used and in the case of natural steroid hormones these have been used to increase mass gain by stimulating protein anabolism. Pesticides have been used for many years in the control of ectoparasites which transmit important human and livestock diseases. The purpose of the present article is to review procedures for management of veterinary products to facilitate national and international trade.
Mostrar más [+] Menos [-]Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texto completo
2009
E.S. Mitema
Drugs, hormones and pesticides are chemical compounds used for alleviation of various diseases in animals. There are many classes of drugs which have been used and in the case of natural steroid hormones these have been used to increase mass gain by stimulating protein anabolism. Pesticides have been used for many years in the control of ectoparasites which transmit important human and livestock diseases. The purpose of the present article is to review procedures for management of veterinary products to facilitate national and international trade.
Mostrar más [+] Menos [-]Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, Crocodylus niloticus Texto completo
2009
Huchzermeyer, F.W. | Wallace, D.B. | Putterill, J.F. | Gerdes, G.H.
Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, Crocodylus niloticus Texto completo
2009
Huchzermeyer, F.W. | Wallace, D.B. | Putterill, J.F. | Gerdes, G.H.
When large numbers of crocodile skins were downgraded because of the presence of small pin pricklike holes, collapsed epidermal cysts were found deep in the dermis of juvenile crocodiles while forming cysts were observed in hatchlings. Histopathology of these forming cysts showed the presence of intracytoplasmic inclusions in proliferating and ballooning epidermal cells. Pox virions were seen in electron microscope preparations made from the scabs of such early lesions. The partial sequencing of virus material from scrapings of these lesions and comparison of it with the published sequence of crocodile poxvirus showed the virus associated with the deep lesions to be closely related, but different. To differentiate between the two forms of crocodile pox infection it is suggested that the previously known form should be called ''classical crocodile pox'' and the newly discovered form ''atypical crocodile pox''. The application of strict hygiene measures brought about a decline in the percentage of downgraded skins.
Mostrar más [+] Menos [-]Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, <i>Crocodylus niloticus</i> Texto completo
2009
F.W. Huchzermeyer | D.B. Wallace | J.F. Putterill | G.H. Gerdes
When large numbers of crocodile skins were downgraded because of the presence of small pin pricklike holes, collapsed epidermal cysts were found deep in the dermis of juvenile crocodiles while forming cysts were observed in hatchlings. Histopathology of these forming cysts showed the presence of intracytoplasmic inclusions in proliferating and ballooning epidermal cells. Pox virions were seen in electron microscope preparations made from the scabs of such early lesions. The partial sequencing of virus material from scrapings of these lesions and comparison of it with the published sequence of crocodile poxvirus showed the virus associated with the deep lesions to be closely related, but different. To differentiate between the two forms of crocodile pox infection it is suggested that the previously known form should be called ''classical crocodile pox'' and the newly discovered form ''atypical crocodile pox''. The application of strict hygiene measures brought about a decline in the percentage of downgraded skins.
Mostrar más [+] Menos [-]Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texto completo
2009
Thomson, G.R.
Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texto completo
2009
Thomson, G.R.
The present international approach to management of transboundary animal diseases (TADs) is based on the assumption that most can be eradicated ; consequently, that is the usual objective adopted by international organizations concerned with animal health. However, for sub-Saharan Africa and southern Africa more particularly, eradication of most TADs is impossible for the foreseeable future for a variety of technical, financial and logistical reasons. Compounding this, the present basis for access to international markets for products derived from animals requires that the area of origin (country or zone) is free from trade-influencing TADs. The ongoing development of transfrontier conservation areas (TFCAs), extending across huge areas of southern Africa, therefore presents a development conundrum because it makes creation of geographic areas free from TADs more difficult and brings development based on wildlife conservation on the one hand and that based on livestock production on the other into sharp conflict. Sub-Saharan Africa is consequently confronted by a complex problem that contributes significantly to retarded rural development which, in turn, impedes poverty alleviation. In southern Africa specifically, foot-and-mouth disease (FMD) presents the greatest problem in relation to access to international markets for animal products. However, it is argued that this problem could be overcome by a combination between (1) implementation of a commodity-based approach to trade in products derived from animals and (2) amendment of the international standards for FMD specifically (i.e. the FMD chapter in the Terrestrial Animal Health Code of the World Organisation for Animal Health [OIE]) so that occurrence of SAT serotype viruses in free-living African buffalo need not necessarily mean exclusion of areas where buffalo occur from international markets for animal products. This would overcome a presently intractable constraint to market access for southern African countries and enable conservation and livestock production to be more effectively integrated, to the benefit of both.
Mostrar más [+] Menos [-]Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texto completo
2009
G.R. Thomson
The present international approach to management of transboundary animal diseases (TADs) is based on the assumption that most can be eradicated ; consequently, that is the usual objective adopted by international organizations concerned with animal health. However, for sub-Saharan Africa and southern Africa more particularly, eradication of most TADs is impossible for the foreseeable future for a variety of technical, financial and logistical reasons. Compounding this, the present basis for access to international markets for products derived from animals requires that the area of origin (country or zone) is free from trade-influencing TADs. The ongoing development of transfrontier conservation areas (TFCAs), extending across huge areas of southern Africa, therefore presents a development conundrum because it makes creation of geographic areas free from TADs more difficult and brings development based on wildlife conservation on the one hand and that based on livestock production on the other into sharp conflict. Sub-Saharan Africa is consequently confronted by a complex problem that contributes significantly to retarded rural development which, in turn, impedes poverty alleviation. In southern Africa specifically, foot-and-mouth disease (FMD) presents the greatest problem in relation to access to international markets for animal products. However, it is argued that this problem could be overcome by a combination between (1) implementation of a commodity-based approach to trade in products derived from animals and (2) amendment of the international standards for FMD specifically (i.e. the FMD chapter in the Terrestrial Animal Health Code of the World Organisation for Animal Health [OIE]) so that occurrence of SAT serotype viruses in free-living African buffalo need not necessarily mean exclusion of areas where buffalo occur from international markets for animal products. This would overcome a presently intractable constraint to market access for southern African countries and enable conservation and livestock production to be more effectively integrated, to the benefit of both.
Mostrar más [+] Menos [-]A century of tick taxonomy in South Africa : tick-borne diseases Texto completo
2009
Horak, I.G.
A century of tick taxonomy in South Africa : tick-borne diseases Texto completo
2009
Horak, I.G.
Eighty ixodid tick species, 25 argasid tick species and Nuttalliella namaqua occur in South Africa. Twenty-one of the 80 ixodid species and two of the argasid species occur only in this country, while N. namaqua is present only in South Africa and Namibia. Forty-six of the 80 ixodid species and 16 of the 25 argasid species as well as N. namaqua have been described as new species since 1908. People working in South Africa have written or contributed to the descriptions of 24 of these 63 new species, while foreign researchers have described the remainder. New species indigenous to South Africa are still being discovered, while the names of some species, well known because of their veterinary importance, have been altered.
Mostrar más [+] Menos [-]A century of tick taxonomy in South Africa : tick-borne diseases Texto completo
2009
I.G. Horak
Eighty ixodid tick species, 25 argasid tick species and Nuttalliella namaqua occur in South Africa. Twenty-one of the 80 ixodid species and two of the argasid species occur only in this country, while N. namaqua is present only in South Africa and Namibia. Forty-six of the 80 ixodid species and 16 of the 25 argasid species as well as N. namaqua have been described as new species since 1908. People working in South Africa have written or contributed to the descriptions of 24 of these 63 new species, while foreign researchers have described the remainder. New species indigenous to South Africa are still being discovered, while the names of some species, well known because of their veterinary importance, have been altered.
Mostrar más [+] Menos [-]Blood platelet counts, morphology and morphometry in lions, Panthera leo Texto completo
2009
Du Plessis, L.
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 109/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, morphometricanalysis 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.
Mostrar más [+] Menos [-]Comparative histopathology of the lymph nodes, spleen, liver and kidney in experimental ovine trypanosomosis Texto completo
2009
Omotainse, S.O. | Anosa, V.O.
Comparative histopathology of the lymph nodes, spleen, liver and kidney in experimental ovine trypanosomosis Texto completo
2009
Omotainse, S.O. | Anosa, V.O.
The infection of Yankassa rams with three important trypanosome species affecting livestock, namely, Trypanosoma congolense, T. vivax and T. brucei produced 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.
Mostrar más [+] Menos [-]Comparative histopathology of the lymph nodes, spleen, liver and kidney in experimental ovine trypanosomosis Texto completo
2009
S.O. Omotainse | V.O. Anosa
The infection of Yankassa rams with three important trypanosome species affecting livestock, namely, Trypanosoma congolense, T. vivax and T. brucei produced 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.
Mostrar más [+] Menos [-]Prevalence of bovine cysticercosis and hydatidosis in Jimma municipal abattoir, South West Ethiopia Texto completo
2009
Tolosa, T. | Tigre, W. | Teka, G. | Dorny, P.
Prevalence of bovine cysticercosis and hydatidosis in Jimma municipal abattoir, South West Ethiopia Texto completo
2009
Tolosa, T. | Tigre, W. | Teka, G. | Dorny, P.
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.
Mostrar más [+] Menos [-]Prevalence of bovine cysticercosis and hydatidosis in Jimma municipal abattoir, South West Ethiopia Texto completo
2009
T. Tolosa | W. Tigre | G. Teka | P. Dorny
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.
Mostrar más [+] Menos [-]Rinderpest : an historical overview : historical overview : Onderstepoort and veterinary research in Africa Texto completo
2009
P. Roeder
Rinderpest : an historical overview : historical overview : Onderstepoort and veterinary research in Africa Texto completo
2009
P. Roeder
Rinderpest is one of the few diseases which have changed the course of world history. Originally an Asian disease, for centuries it had a devastating impact in Europe when introduced by returning and marauding armies accompanied by cattle as well as by cattle trade. Nowhere was its impact more dramatically expressed than in Africa where the sequel to its introduction into the Horn of Africa was a devastating panzootic throughout sub-Saharan Africa during the last decade of the 19th century extending into the 20th century. Massive deaths of livestock, wild animals and the people dependent on them led to widespread human misery and changed the face of the African continent forever.
Mostrar más [+] Menos [-]Rinderpest : an historical overview : historical overview : Onderstepoort and veterinary research in Africa Texto completo
2009
Roeder, P.
Rinderpest is one of the few diseases which have changed the course of world history. Originally an Asian disease, for centuries it had a devastating impact in Europe when introduced by returning and marauding armies accompanied by cattle as well as by cattle trade. Nowhere was its impact more dramatically expressed than in Africa where the sequel to its introduction into the Horn of Africa was a devastating panzootic throughout sub-Saharan Africa during the last decade of the 19th century extending into the 20th century. Massive deaths of livestock, wild animals and the people dependent on them led to widespread human misery and changed the face of the African continent forever.
Mostrar más [+] Menos [-]