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Livestock policy and trade issues in SADC : policy and trade issues Texte intégral
2009
Hulman, B.
Livestock policy and trade issues in SADC : policy and trade issues Texte intégral
2009
Hulman, B.
As from 2001, the Southern African Development Community (SADC) has embarked on a course to deepen regional integration through restructuring. Under the new structure SADC has centralised the coordination of its activities to the Secretariat in Gaborone. The former Sector Coordinating Units have been merged into four directorates, one of which is the Food, Agriculture and Natural Resources (FANR) Directorate, which comprises, amongst others, the Livestock Development Unit (LDU).
Afficher plus [+] Moins [-]Livestock policy and trade issues in SADC : policy and trade issues Texte intégral
2009
B. Hulman
As from 2001, the Southern African Development Community (SADC) has embarked on a course to deepen regional integration through restructuring. Under the new structure SADC has centralised the coordination of its activities to the Secretariat in Gaborone. The former Sector Coordinating Units have been merged into four directorates, one of which is the Food, Agriculture and Natural Resources (FANR) Directorate, which comprises, amongst others, the Livestock Development Unit (LDU).
Afficher plus [+] Moins [-]Curtisia dentata (Cornaceae) leaf extracts and isolated compounds inhibit motility of parasitic and free-living nematodes Texte intégral
2009
Shai, L.J. | Bizimenyera, E.S. | Bagla, V. | McGaw, L.J. | Eloff, J.N.
Curtisia dentata (Cornaceae) leaf extracts and isolated compounds inhibit motility of parasitic and free-living nematodes Texte intégral
2009
Shai, L.J. | Bizimenyera, E.S. | Bagla, V. | McGaw, L.J. | Eloff, J.N.
Haemonchus contortus and Trichostrongylus colubriformis are among the most important parasitic nematodes of small ruminants. Caenorhabditis elegans, a free-living nematode, is used as a model for evaluating anthelmintic activity of a variety of test substances. Extracts of several medicinal plants are useful in vitro and in vivo against nematode development. Extracts of Curtisia dentata, a South African medicinal plant, and compounds isolated from leaves of this plant were investigated for anthelmintic activity against T. colubriformis, H. contortus and C. elegans. The acetone and dichloromethane extracts were active against all nematodes at concentrations as low as 160 g/mℓ. Betulinic acid and lupeol were active against the parasitic nematodes only at the high concentrations of 1 000 and 200 g/mℓ, respectively. All compounds were effective against C. elegans with active concentrations as low as 8 g/mℓ. Betulinic acid was less active than lupeol and ursolic acid against C. elegans. The acetone and dichloromethane extracts were also active against C. elegans with a concentration of 0.31 mg/mℓ resulting in almost 80 % inhibition of larval motility. The use of free-living nematodes may provide information on the activity of potential anthelmintics against parasitic nematodes. Extracts of various medicinal plant species may provide solutions to ill-health of small ruminants caused by parasitic nematodes in poor communities of southern Africa.
Afficher plus [+] Moins [-]<i>Curtisia dentata</i> (Cornaceae) leaf extracts and isolated compounds inhibit motility of parasitic and free-living nematodes Texte intégral
2009
L.J. Shai | E.S. Bizimenyera | V. Bagla | L.J. McGaw | J.N. Eloff
Haemonchus contortus and Trichostrongylus colubriformis are among the most important parasitic nematodes of small ruminants. Caenorhabditis elegans, a free-living nematode, is used as a model for evaluating anthelmintic activity of a variety of test substances. Extracts of several medicinal plants are useful in vitro and in vivo against nematode development. Extracts of Curtisia dentata, a South African medicinal plant, and compounds isolated from leaves of this plant were investigated for anthelmintic activity against T. colubriformis, H. contortus and C. elegans. The acetone and dichloromethane extracts were active against all nematodes at concentrations as low as 160 μg/mℓ. Betulinic acid and lupeol were active against the parasitic nematodes only at the high concentrations of 1 000 and 200 μg/mℓ, respectively. All compounds were effective against C. elegans with active concentrations as low as 8 μg/mℓ. Betulinic acid was less active than lupeol and ursolic acid against C. elegans. The acetone and dichloromethane extracts were also active against C. elegans with a concentration of 0.31 mg/mℓ resulting in almost 80 % inhibition of larval motility. The use of free-living nematodes may provide information on the activity of potential anthelmintics against parasitic nematodes. Extracts of various medicinal plant species may provide solutions to ill-health of small ruminants caused by parasitic nematodes in poor communities of southern Africa.
Afficher plus [+] Moins [-]The future of private veterinary practice in South Africa : animal health management in the 21st Texte intégral
2009
Marwick, C.
The future of private veterinary practice in South Africa : animal health management in the 21st Texte intégral
2009
Marwick, C.
Private practice became the major vocation of local veterinarians from about 1945. Soga was probably the first qualified South African veterinarian to practice privately on a limited scale in the 1800s. Jack Boswell was the first locally qualified (in 1934) veterinarian to go directly into practice without first working for the government and is regarded as the father of private practice in South Africa. Boet Bekker worked for the government before setting up a successful practice in 1935.
Afficher plus [+] Moins [-]The future of private veterinary practice in South Africa : animal health management in the 21st Texte intégral
2009
C. Marwick
Private practice became the major vocation of local veterinarians from about 1945. Soga was probably the first qualified South African veterinarian to practice privately on a limited scale in the 1800s. Jack Boswell was the first locally qualified (in 1934) veterinarian to go directly into practice without first working for the government and is regarded as the father of private practice in South Africa. Boet Bekker worked for the government before setting up a successful practice in 1935.
Afficher plus [+] Moins [-]Canine babesiosis : tick-borne diseases Texte intégral
2009
Schoeman, J.P.
Canine babesiosis : tick-borne diseases Texte intégral
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.
Afficher plus [+] Moins [-]Canine babesiosis : tick-borne diseases Texte intégral
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.
Afficher plus [+] Moins [-]Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features Texte intégral
2009
Crole, M.R. | Soley, J.T.
Morphology of the tongue of the emu (Dromaius novaehollandiae). II. Histological features Texte intégral
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.
Afficher plus [+] Moins [-]Morphology of the tongue of the emu (<i>Dromaius novaehollandiae</i>). II. Histological features Texte intégral
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.
Afficher plus [+] Moins [-]Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texte intégral
2009
Mitema, E.S.
Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texte intégral
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.
Afficher plus [+] Moins [-]Improved management of drugs, hormones and pesticides in Africa : policy and trade issues Texte intégral
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.
Afficher plus [+] Moins [-]Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, Crocodylus niloticus Texte intégral
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 Texte intégral
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.
Afficher plus [+] Moins [-]Identification and partial sequencing of a crocodile poxvirus associated with deeply penetrating skin lesions in farmed Nile crocodiles, <i>Crocodylus niloticus</i> Texte intégral
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.
Afficher plus [+] Moins [-]Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texte intégral
2009
Thomson, G.R.
Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texte intégral
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.
Afficher plus [+] Moins [-]Currently important animal disease management issues in sub-Saharan Africa : policy and trade issues Texte intégral
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.
Afficher plus [+] Moins [-]A century of tick taxonomy in South Africa : tick-borne diseases Texte intégral
2009
Horak, I.G.
A century of tick taxonomy in South Africa : tick-borne diseases Texte intégral
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.
Afficher plus [+] Moins [-]A century of tick taxonomy in South Africa : tick-borne diseases Texte intégral
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.
Afficher plus [+] Moins [-]Blood platelet counts, morphology and morphometry in lions, Panthera leo Texte intégral
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.
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