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2-Phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from Sea World to uShaka Marine World, South Africa
2008
Vaughan, D.B.(Two Oceans Aquarium Dock Road Victoria and Alfred Waterfront) | Penning, M.R.(South African Association for Marine Biological Research uShaka Marine World) | Christison, K.W.(University of the Western Cape Department of Biodiversity and Conservation Biology)
2-Phenoxyethanol was used as an anaesthetic to translocate 102 species of fishes representing 30 families from the Sea World aquarium on Durban's beachfront to uShaka Marine World. Most fishes responded well to a final anaesthetic concentration of 0,150 mí/í and there were no mortalities.
Mostrar más [+] Menos [-]Relative economic benefits of tactical anthelmintic treatment and urea-molasses block supplementation of Boer goats raised under extensive grazing conditions at Onderstepoort, Pretoria, South Africa
2008
Vatta, A.F.(Onderstepoort Veterinary Institute ,University of KwaZulu-Natal) | Krecek, R.C.(University of Johannesburg) | Pearson, R.A.(University of Edinburgh Royal (Dick) School of Veterinary Studies Division of Veterinary Clinical Science (incorporating Centre for Tropical Veterinary Medicine)) | Smith, M.F.(Agricultural Research Council) | Stenson, M.O.(Onderstepoort Veterinary Institute) | Van Wijk, E.F.(Onderstepoort Veterinary Institute) | Harrison, L.J.S.(University of Edinburgh Royal (Dick) School of Veterinary Studies Division of Veterinary Clinical Science (incorporating Centre for Tropical Veterinary Medicine))
The potential economic benefits of combining tactical anthelmintic treatment for gastrointestinal nematodes and nutritional supplementation with urea-molasses blocks were examined in Boer goats raised under extensive grazing conditions in the summer rainfall area of South Africa. Eight groups of nine goats were monitored over a 12-month period from 1 October 2002 to 9 October 2003. Ad libitum nutritional supplementation with urea-molasses blocks was provided when the goats were housed at night, during the summer (wet season-December 2002 to February 2003), and/or the winter (dry season-June 2003 to August 2003). All the goats were treated symptomatically for Haemonchus contortus infection when deemed necessary by clinical examination of the conjunctiva for anaemia using the FAMACHA© system. Half the groups were tactically treated for gastrointestinal nematodes in mid-summer (28 January 2003). Under the symptomatic treatment, climatic and extensive grazing conditions encountered during the trial, feed supplementation in the winter dry season had the greatest economic benefit and is therefore recommended. Tactical anthelmintic treatment afforded no additional advantage, but the nematode challenge was low.
Mostrar más [+] Menos [-]Intramammary antibiotic withdrawal periods for dairy goats compared to those for dairy cattle
2008
Petzer, I.M.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Donkin, E.F.(University of Pretoria Faculty of Natural and Agricultural Sciences Department of Animal and Wildlife Sciences) | Du Preez, E.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Karzis, J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Van Der Schans, T.J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Watermeyer, J.C.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Van Reenen, R.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
This study investigated the withdrawal periods (WP) of two intramammary antibiotics Cloxamast LC (Intervet SA) and Spectrazol Milking Cow (Schering-Plough Animal Health) in dairy goats and compared them to those recommended for use in cattle. The WP for Cloxamast LC, measured by the Thermo Resistant Inhibitory Substances (TRIS) test, was 60 h in composite samples, 56 h in udder half samples, and the dye was visible for up to 56 h. The WP was significantly shorter than the 72 h recommended WP for use in cattle. It was however significantly longer when the 24 h safety margin (48 h) was subtracted from the recommended WP for cattle. For Spectrazol Milking Cow the antibiotics could be detected by the TRIS test for 61 h in composite samples and 59 h in udder half samples. This did not differ significantly from the recommended 60 h WP for cattle. However, it was significantly longer than that recommended for use in cattle without the 24 h safety margin. There was no significant difference in WP between infected and non-infected udder halves, while there was a weak positive correlation between WP and stage of lactation (R² = 0.253). There was a moderate positive correlation (R² = 0.583) between the TRIS test and the presence of dye in milk in udder half samples and between WP in both udder half and composite milk samples (R² = 0.456). Weak to moderate positive correlations were present between milk yield and the WP in both udder half (R² = 0.414) and composite (R² = 0.262) milk samples. Significant differences (P < 0.001) were also observed between the milk yield of udder halves with and without palpable udder damage and between samples that tested TRIS positive and negative on both composite (P = 0.008) and udder half samples (P < 0.001). There was no significant difference between the milk yield of samples with or without dye. There was a significant difference in milk yield between infected and non-infected udder halves (P = 0.054) and a weak negative correlation between milk yield and stage of lactation (R² = -0.379).
Mostrar más [+] Menos [-]Evaluation of larvicides in developing management guidelines for long-term control of pest blackflies (Diptera: Simuliidae) along the Orange River, South Africa
2008
Palmer, R.W.(Nepid Consultants) | Rivers-Moore, N.A.(Rhodes University Institute for Water Research)
In 2000 and 2001 Orange River levels were higher than normal: associated serious outbreaks of blackfly had a substantial detrimental impact on the local economy. The poor control was attributed to the suspected development of larval resistance to temephos. A long-term solution to blackfly control, through the identification of a suitable replacement to temephos for use during high flow conditions, was proposed. This study, however, failed to identify or register a suitable larvicide for use during high flow conditions. Although permethrin was highly effective against blackfly larvae, it was rejected because of its detrimental impacts on non-target fauna. Various formulations of locally produced dry Bacillus thuringiensis var. israelensis (B.t.i.) were tested, but these were ineffective against blackflies. The study also confirmed that resistance to temephos has developed among Simulium chutteri in the middle and lower Orange River. The feasibility of "reversing" the resistance to temephos through the use of the synergist piperonyl butoxide (PEO) was investigated, but the results were not favourable. Furthermore, PBO was highly toxic to blackflies and non-target organisms, and was not recommended for further testing. This means that B.t.i. currently remains the only symptomatic measure of treatment currently applied. Although resistance to B.t.i. has not been reported for blackflies elsewhere in South Africa, there is a need to remain vigilant and to implement an operational strategy that minimizes the risks of resistance developing.
Mostrar más [+] Menos [-]Prevalence of the dog nematode Spirocerca lupi in populations of its intermediate dung beetle host in the Tshwane (Pretoria) Metropole, South Africa
2008
du Toit, C.A.(University of Pretoria Department of Zoology and Entomology Scarab Research Group) | Scholtz, C.H.(University of Pretoria Department of Zoology and Entomology Scarab Research Group) | Hyman, W.B.(Vet-Pharm)
Spirocerca lupi (Spirurida: Spirocercidae) is a cosmopolitan parasite, principally of domestic dogs and dung beetles are its main intermediate hosts. In South Africa there has recently been growing concern over the upsurge of reported cases of clinical spirocercosis in dogs, while little is known or understood about the dynamics of the host-parasite associations between dung beetles and this nematode. We determined and compared the prevalence of infection in dung beetles between rural, urban and periurban areas of Tshwane (Pretoria) Metropole. Dung beetles were sampled during April and October 2006, at various localities in each of these areas. Localities were selected on the basis of being focal areas of high infection with S. lupi in dogs. Pig, dog and cow dung-baited pitfall traps were used for sampling the beetles. Trap contents were collected 48 h after the traps had been set and only dung beetles were collected from the traps. In total, 453 specimens belonging to 18 species were collected from 63 pitfall traps in all three areas. The numbers of species that were collected varied among the three areas. Dung beetles, irrespective of species (18) and numbers (447), predominantly preferred pig dung. The prevalence of dung beetles infected with the larvae of S. lupi varied considerably in the three areas. In the urban area 13.5 % of the dung beetles dissected were infected, while the prevalence of S. lupi in dung beetles in the rural area was 2.3 %. All the dung beetles that were infected with this nematode showed a preference for omnivore (pig and dog) dung.
Mostrar más [+] Menos [-]A rapid and sensitive real-time reverse transcription PCR for the pathotyping of South African H5N2 avian influenza viruses
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.
Mostrar más [+] Menos [-]Epidemiological survey on gastro-intestinal and blood-borne helminths of dogs in north-east Gabon
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.
Mostrar más [+] Menos [-]Detection of respiratory pathogens in air samples from acutely infected pigs
2008
Hermann, J.R. | Brockmeier, S.L. | Yoon, K.J. | Zimmerman, J.J.
Pathogens causing significant respiratory disease in growing pigs include Porcine reproductive and respiratory syndrome virus, Porcine circovirus 2, swine influenza virus, porcine respiratory coronavirus, Mycoplasma hyopneumoniae, and Bordetella bronchiseptica. The objective of this research was to characterize the respiratory excretion of these pathogens by acutely infected pigs. Pigs were inoculated under experimental conditions with 1 pathogen. Samples were collected from the upper respiratory tract and exhaled air. All pathogens were detected in swabs of the upper respiratory tract, but only M. hyopneumoniae and B. bronchiseptica were detected in expired air from individually sampled, acutely infected pigs. These findings suggest either that the acutely infected pigs did not aerosolize the viruses or that the quantity of virus excreted was below the detection threshold of current sampling or assay systems, or both, at the individual-pig level.
Mostrar más [+] Menos [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004)
2008
P. G. Howell | Jane P. Nurton | Daleen Nel | Carina W. Lourens | A. J. Guthrie
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 in fections 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.
Mostrar más [+] Menos [-]Value of tests for evaluating udder health in dairy goats: somatic cell counts, California Milk Cell Test and electrical conductivity
2008
I.M. Petzer | E.F. Donkin | E. Du Preez | J. Karzis | T.J. Van der schans | J.C. Watermeyer | R. Van Reenen
The value of electric conductivity (EC), California Milk Cell Test (CMCT) and somatic cell count (SCC) as diagnostic tools was investigated in dairy goats. Conductivity colour reading correlated with SCC. Milk samples with conductivity colour red had significantly higher SCC than those with conductivity colours green and orange (P < 0.001). There were moderate positive correlations between CMCT (R2 = 0.470), and conductivity score and CMCT and conductivity colour readings (R2 = 0.597). Conductivity scores were significantly (P < 0.001) higher during and after intra-mammary treatment with Cloxamast LC and conductivity colours were significantly different between treatment and control groups (P < 0.001). There was a weak positive correlation between conductivity colour and stage of lactation (R2 = 0.317) and a moderately positive correlation between conductivity score and stage of lactation (R2 = 0.523). A moderately negative correlation was shown between milk yield and conductivity score (R2 = -0.426) and between milk yield and conductivity colour (R2 = -0.433). Moderate positive correlations were present between CMCT and SCC (R2 = 0.689) and between CMCT and stage of lactation (R2 = 0.459). CMCT ratings were significantly different (P < 0.001) for the intramammary treatment groups. CMCT ratings for infected and non-infected udder halves (P = 0.008) were significantly different; as were those for infected and non-infected udder halves and for left and right udder halves separately (P = 0.010). CMCT ratings for milk samples with SCC above and below 750 x 103 cells per mℓ were significantly different (P < 0.001) as well as for milk from treated and control udder halves with SCC below or above 750 x 103 cells per mℓ (P < 0.001). CMCT was found to be more accurate for indicating the absence of mastitis than for diagnosing it. There were significant differences in log SCC between treatment and control groups, during and after treatment. Infected udder halves had significantly higher log SCC than non-infected udder halves before and after treatment, but not during treatment. There was a moderate positive correlation between stage of lactation and SCC (R2 = 0.438).
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