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Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Full text
2008
Specht, E.J.K.(Laboratório Regional de Veterinária)
Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Full text
2008
Specht, E.J.K.(Laboratório Regional de Veterinária)
The study is the result of analyzing 16 895 blood smears of cattle collected at 180 sites in the provinces of Manica, Sofala, Zambézia and Tete in Mozambique. Of the blood smears 73.9 % were from Manica, 11.8 % from Tete, 8.5 % from Sofala and 5.8 % from Zambézia; 75.6 % of these were collected from smallholder cattle. Infections with trypanosomes were highest in smallholder cattle from Sofala Province with 36.8 % of the 872 blood smears examined positive for trypanosomes, and lowest in cattle of commercial farmers in Manica Province with only 6.2 % of 2 252 blood smears being positive. Trypanosoma congolense was the predominant species, followed by Trypanosoma vivax and Trypanosoma brucei sensu lato. Trypanosoma brucei, which also infects humans, was more frequent in the districts of Buzi, Mutarara and Morrumbala with 15.1 %, 10.5 % and 9.8 % of all examined cattle in 2005 being infected with it, respectively. The results show a significant increase in the infection rate with trypanosomes compared with results obtained in previous years by the Regional Veterinary Laboratory in Manica Province and by the Regional Tsetse and Trypanosomiasis Control Programme in Zambézia, Tete and Sofala provinces.
Show more [+] Less [-]Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Full text
2008
E.J.K. Specht
The study is the result of analyzing 16 895 blood smears of cattle collected at 180 sites in the provinces of Manica, Sofala, Zambézia and Tete in Mozambique. Of the blood smears 73.9 % were from Manica, 11.8 % from Tete, 8.5 % from Sofala and 5.8 % from Zambézia; 75.6 % of these were collected from smallholder cattle. Infections with trypanosomes were highest in smallholder cattle from Sofala Province with 36.8 % of the 872 blood smears examined positive for trypanosomes, and lowest in cattle of commercial farmers in Manica Province with only 6.2 % of 2 252 blood smears being positive. Trypanosoma congolense was the predominant species, followed by Trypanosoma vivax and Trypanosoma brucei sensu lato. Trypanosoma brucei, which also infects humans, was more frequent in the districts of Buzi, Mutarara and Morrumbala with 15.1 %, 10.5 % and 9.8 % of all examined cattle in 2005 being infected with it, respectively. The results show a significant increase in the infection rate with trypanosomes compared with results obtained in previous years by the Regional Veterinary Laboratory in Manica Province and by the Regional Tsetse and Trypanosomiasis Control Programme in Zambézia, Tete and Sofala provinces.
Show more [+] Less [-]Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle Full text
2008
Strydom, S.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Agenäs, S.(Swedish University of Agricultural Sciences Department of Animal Nutrition and Management Kungsangen Research Centre) | Heath, M.F.(University of Cambridge Department of Veterinary Medicine) | Phillips, C.J.C.(University of Queensland School of Veterinary Science Centre for Animal Welfare and Ethics) | Rautenbach, G.H.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Thompson, P.N.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle Full text
2008
Strydom, S.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Agenäs, S.(Swedish University of Agricultural Sciences Department of Animal Nutrition and Management Kungsangen Research Centre) | Heath, M.F.(University of Cambridge Department of Veterinary Medicine) | Phillips, C.J.C.(University of Queensland School of Veterinary Science Centre for Animal Welfare and Ethics) | Rautenbach, G.H.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Thompson, P.N.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
Body condition scoring (BCS) gives an indication of the nutritional status of an animal and it is thus an invaluable management tool in domestic livestock systems. It is, however, subjective. This study aimed at identifying biochemical indicators which could be objectively used as an indicator of undernutrition in ruminants. Blood samples were collected from 50 cattle with BCS < 1 and from 50 cattle with BCS > 2.5, using a 0-5 scale, and analysed for albumin, urea, creatinine, fructosamine, beta-hydroxybutyrate, non-esterified fatty acids, total serum protein and haematocrit. Rumpfat and ribfat thickness and marbling relative index were determined ultrasonographically in 15 of the low BCS group and 13 of the high BCS group. The laboratory measure with the best predictive ability for severe undernutrition was albumin, which correctly classified 94 % of cattle, using a cut-off of 31.5 g/l. In contrast to a previous study, our study did not find the fructosamine:albumin ratio to be an accurate test to indicate undernutrition in cattle. Ultrasonic measurement of subcutaneous rumpfat and ribfat proved to reliably predict undernutrition, but may, however be impractical for routine use under most field conditions.
Show more [+] Less [-]Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle Full text
2008
S. Strydom | S. Agenas | M.F. Heath | C.J.C. Phillips | G.H. Rautenbach | P.N. Thompson
Body condition scoring (BCS) gives an indication of the nutritional status of an animal and it is thus an invaluable management tool in domestic livestock systems. It is, however, subjective. This study aimed at identifying biochemical indicators which could be objectively used as an indicator of undernutrition in ruminants. Blood samples were collected from 50 cattle with BCS ≤ 1 and from 50 cattle with BCS ≥ 2.5, using a 0-5 scale, and analysed for albumin, urea, creatinine, fructosamine, beta-hydroxybutyrate, non-esterified fatty acids, total serum protein and haematocrit. Rumpfat and ribfat thickness and marbling relative index were determined ultrasonographically in 15 of the low BCS group and 13 of the high BCS group. The laboratory measure with the best predictive ability for severe undernutrition was albumin, which correctly classified 94 % of cattle, using a cut-off of 31.5 g / ℓ. In contrast to a previous study, our study did not find the fructosamine : albumin ratio to be an accurate test to indicate undernutrition in cattle. Ultrasonic measurement of subcutaneous rumpfat and ribfat proved to reliably predict undernutrition, but may, however be impractical for routine use under most field conditions.
Show more [+] Less [-]Pentastomid parasites in fish in the Olifants and Incomati River systems, South Africa Full text
2008
Luus-Powell, Wilmien J.(University of Limpopo Department of Biodiversity) | Jooste, Antoinette(University of Limpopo Department of Biodiversity) | Junker, Kerstin(University of Pretoria Department of Veterinary Tropical Diseases)
Pentastomid parasites in fish in the Olifants and Incomati River systems, South Africa Full text
2008
Luus-Powell, Wilmien J.(University of Limpopo Department of Biodiversity) | Jooste, Antoinette(University of Limpopo Department of Biodiversity) | Junker, Kerstin(University of Pretoria Department of Veterinary Tropical Diseases)
During parasitological field surveys of freshwater fish, sebekiid and subtriquetrid pentastome larvae were recovered from the body cavity or swim bladder of several fish species from various localities in Limpopo and Mpumalanga Provinces, South Africa. Sebekia wedliwas recovered from the body cavity of Marcusenius macrolepidotus (Mormyridae) from Flag Boshielo Dam, Limpopo Province, and Alofia sp. and Subtriquetra rileyi were found in the swim bladder of Oreochromis mossambicus (Cichlidae) from the Phalaborwa Barrage, Limpopo Province. The latter species was also collected from the swim bladder of O. mossambicus in dams in the Phalaborwa region and the Ga-Selati River, Limpopo Province. A single specimen of Sebekia okavangoensis was present in the body cavity of Clarias gariepinus (Clariidae) in a dam on a sugarcane farm in the Komatipoort region, Mpumalanga Province. Pentastomid infections in the Mormyridae and Clariidae represent new host records.
Show more [+] Less [-]Pentastomid parasites in fish in the Olifants and Incomati River systems, South Africa Full text
2008
Wilmien J. Luus-Powell | Antoinette Jooste | Kerstin Junker
During parasitological field surveys of freshwater fish, sebekiid and subtriquetrid pentastome larvae were recovered from the body cavity or swim bladder of several fish species from various localities in Limpopo and Mpumalanga Provinces, South Africa. Sebekia wedli was recovered from the body cavity of Marcusenius macrolepidotus (Mormyridae) from Flag Boshielo Dam, Limpopo Province, and Alofia sp. and Subtriquetra rileyi were found in the swim bladder of Oreochromis mossambicus (Cichlidae) from the Phalaborwa Barrage, Limpopo Province. The latter species was also collected from the swim bladder of O. mossambicus in dams in the Phalaborwa region and the Ga-Selati River, Limpopo Province. A single specimen of Sebekia okavangoensis was present in the body cavity of Clarias gariepinus (Clariidae) in a dam on a sugarcane farm in the Komatipoort region, Mpumalanga Province. Pentastomid infections in the Mormyridae and Clariidae represent new host records.
Show more [+] Less [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings in South Africa (1999-2004) Full text
2008
Howell, P.G.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Nurton, Jane P.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Nel, Daleen(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Lourens, Carina W.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Guthrie, A.J.(University of Pretoria Faculty of Veterinary Science Equine Research Centre)
Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings in South Africa (1999-2004) Full text
2008
Howell, P.G.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Nurton, Jane P.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Nel, Daleen(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Lourens, Carina W.(University of Pretoria Faculty of Veterinary Science Equine Research Centre) | Guthrie, A.J.(University of Pretoria Faculty of Veterinary Science Equine Research Centre)
Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6 % and 34.7 %, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and localized infections affecting only individual horses. This study of the seasonal prevalence of equine encephalosis virus has a corollary and serves as a useful model in the seasonal incidence of the serotypes of African horse sickness and bluetongue in regions where the respective diseases are endemic.
Show more [+] Less [-]Haemophilus paragallinarum haemagglutinin: Role in adhesion, serotyping and pathogenicity Full text
2008
Barnard, T.G.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Van Heerden, E.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Bragg, R.R.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Albertyn, J.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology)
It is suggested that Haemophilus paragallinarum requires at least three haemagglutinins for adhesion during infection. This paper reports the partial purification and characterization of the HA-L haemagglutinin from H. paragallinarum strain 46-C3, a heat sensitive, trypsin sensitive haemagglutinin that has been shown to be the serovar specific haemagglutinin in this organism. Using the pi and molecular mass 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.
Show more [+] Less [-]Production trials involving use of the FAMACHA© system for haemonchosis in sheep: Preliminary results Full text
2008
van Wyk, J.A.
In three trials conducted on two separate farms the production of sheep treated for naturally acquired haemonchosis using the FAMACHA© system of targeted selective treatment (TST) (i.e. to treat only those animals unable to manage unaided in the face of heavy Haemonchus challenge) was compared to that of suppressively drenched sheep in the same flock. As expected by the research team who developed and evaluated the FAMACHA© system, TST did result in some loss in production. However, despite high levels of worm challenge in two of the trials and the fact that the comparison was with suppressive drenching which is not sustainable, the total effect was relatively small in relation to the important advantage of using the TST as regards reduced selection for anthelmintic resistance (AR). Concerning the sustainability of worm control, it is concluded that the development of drug resistance to anthelmintics leaves sheep and goat farmers in South Africa no choice but to use methods of TST such as FAMACHA©. The FAMACHA© system can also be a useful clinical aid for early on-farm detection of AR by farmers; the degree of improvement in the colour of the ocular mucous membrane from pale to red in individually drenched anaemic animals over a period of 7-14 days can give a good indication of the efficacy of the compound(s) used.
Show more [+] Less [-]Bovine intestinal cellular responses following primary and challenge infections with Calicophoron microbothrium metacercariae Full text
2008
Mavenyengwa, M.(University of Zimbabwe Department of Paraclinical Veterinary Studies Faculty of Veterinary Science) | Mukaratirwa, S.(University of KwaZulu-Natal School of Biological and Conservation Sciences) | Obwolo, M.(University of Zimbabwe Department of Paraclinical Veterinary Studies Faculty of Veterinary Science) | Monrad, J.(Danish Centre for Experimental Parasitology)
This study was carried out to establish whether cattle can develop resistance to re-infection by Calicophoron microbothrium by assessing the response of intestinal mucosal globule leukocytes, eosinophils, mast cells and basophils, and the establishment of the parasite in the host. A total of 24 1-year-old Tuli steers were randomly divided into four groups of six animals each and infected with C. microbothrium metacercariae. On the first day of the study, animals in Groups I and II were immunized with 5 000 metacercariae and then challenged with 15 000 metacercariae on Day 150 post-immunization. Animals in Group III were immunized with 15 000 metacercariae at the same time that Groups I and II animals were challenged to act as a positive control group. Animals in Group IV were left uninfected and acted as a negative control group. Three animals from each group were slaughtered on Day 28 post-challenge and the remainder were slaughtered on Day 42 post-challenge. The established amphistomes were recovered and histopathological and cytological examinations were done on the jejunum, duodenum, abomasum and the rumen. The establishment rates of the challenge infection in the immunized and challenged groups were lower and ranged from 0 to 0.2 % as compared to 6 %> from naive animals infected as positive controls. Animals immunized and then challenged with C. microbothrium had significantly higher eosinophil, mast cell and globule leukocytes counts in the intestinal mucosa (P < 0.05) as compared to those of the control group. The study indicates that cattle can develop resistance to C. microbothrium re-infection and that eosinophils and mast cells may be important cells in the rejection of the parasite.
Show more [+] Less [-]Studies on effects of lactose on experimental Trypanosoma vivax infection in Zebu cattle. 1. Plasma kinetics of intravenously administered lactose at onset of infection and pathology Full text
2008
Fatihu, M.Y.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Adamu, S.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Umar, I.A.(Ahmadu Bello University Department of Biochemistry) | Ibrahim, N.D.G.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Eduvie, L.O.(Ahmadu Bello University National Animal Production Research Institute) | Esievo, K.A.N.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology)
Lactose in normal saline was administered intravenously to a group of Zebu cattle infected with Trypanosoma vivax to determine the blood plasma 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. Significantly (P < 0.01) higher lactose concentrations were observed in the T. vivax-infected bulls at 30 min and 1 h (P < 0.05) post-infection (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 pre-infusion level in the uninfected group. Calculated pharmacokinetic parameters revealed delayed excretion of lactose in the T. w'vax-infected group soon after infection. The total body clearance (CI B) was significantly (P < 0.05) reduced. The biological half-life (t ½), elimination rate constant (k e) 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. It 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 (despite higher parasitaemia) had no gross or histopathological lesions in the brain, spleen, lymph nodes, 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 adipose tissue, hepatomegaly, splenomegaly, swollen and oedematous lymph nodes, all of which are suggestive of trypanosomosis. Histopathological lesions included narrowing of Bowman's space and hypercellularity of glomerular tufts in the kidneys with the mean glomerular tuft nuclear indices (GTNs) in the group significantly higher (P< 0.01) than the mean GTNs of the lactose-infused and control bulls. Degenerative changes occurred in the myocardium, spleen, testes and epididymides. The tesicular and epididymal lesions are indicative of male reproductive dysfunction.
Show more [+] Less [-]A rapid and sensitive real-time reverse transcription PCR for the pathotyping of South African H5N2 avian influenza viruses Full text
2008
Abolnik, C.(ARC-Onderstepoort Veterinary Institute)
A Fluorescence resonance energy transfer (FRET) real-time reverse-transcription (rRT-PCR) assay was developed that distinguishes stains of South African and European highly pathogenic (HPAI) from low pathogenicity (LPAI) H5 avian influenza viruses in the absence of virus isolation, irrespective of the length of insertion at the hemagglutinin cleavage site (H0). The assay was used to pathotype H5-type viruses detected by rRT-PCR in ostrich tracheal swabs collected during the 2006 HPAI H5N2 outbreak in the Western Cape Province.
Show more [+] Less [-]Epidemiological survey on gastro-intestinal and blood-borne helminths of dogs in north-east Gabon Full text
2008
Davoust, B.(Direction régionale du service de santé des armées de Toulon) | Normand, T.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie ,Centre national d'instruction cynophile de la Gendarmerie Service vétérinaire) | Bourry, O.(Centre international de recherches médicales) | Dang, H.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie) | Leroy, E.(Centre international de recherches médicales ,Institut de recherche pour le développement) | Bourdoiseau, G.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie)
A survey of helminth parasites was carried out on 198 dogs living in almost complete liberty in villages in the northeast of Gabon. Faeces and blood samples were collected and analysed. Dirofilaria immitis antigen was detected in 13.6 % of dogs using the SNAP 3Dx® test, a commercially available enzyme-linked immunosorbent assay (ELISA). Faecal examination revealed that 91.4 % of dogs were infected by intestinal helminths. Ascarids were found in 58.5 % of the samples. Trichuris vulpis was observed in 49.5 %> of cases, and Uncinaria spp. and Ancylostoma spp. in 34.8 %>, Spirocerca lupi in 25.3 % and Capillaria spp. in 10.6 %. Cestode embryophores were found in 8.6 % of the samples.
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