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Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle Texte intégral
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 Texte intégral
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.
Afficher plus [+] Moins [-]Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle Texte intégral
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.
Afficher plus [+] Moins [-]Pentastomid parasites in fish in the Olifants and Incomati River systems, South Africa Texte intégral
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 Texte intégral
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.
Afficher plus [+] Moins [-]Pentastomid parasites in fish in the Olifants and Incomati River systems, South Africa Texte intégral
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.
Afficher plus [+] Moins [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings in South Africa (1999-2004) Texte intégral
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) Texte intégral
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.
Afficher plus [+] Moins [-]Evaluation of larvicides in developing management guidelines for long-term control of pest blackflies (Diptera: Simuliidae) along the Orange River, South Africa Texte intégral
2008
R.W. Palmer | N.A. Rivers-Moore
Evaluation of larvicides in developing management guidelines for long-term control of pest blackflies (Diptera: Simuliidae) along the Orange River, South Africa Texte intégral
2008
R.W. Palmer | N.A. Rivers-Moore
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 (PBO) 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.
Afficher plus [+] Moins [-]Evaluation of larvicides in developing management guidelines for long-term control of pest blackflies (Diptera: Simuliidae) along the Orange River, South Africa Texte intégral
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.
Afficher plus [+] Moins [-]<i>Haemophilus paragallinarum</i> haemagglutinin : role in adhesion, serotyping and pathogenicity Texte intégral
2008
T.G. Barnard | E. Van Heerden | R.R. Bragg | J. Albertyn
It is suggested that Haemophilus paragallinarum requires at least three haemagglutinins for adhesionduring infection. This paper reports the partial purification and characterization of the HA-L haemagglutininfrom H. paragallinarum strain 46-C3, a heat sensitive, trypsin sensitive haemagglutinin that hasbeen shown to be the serovar specific haemagglutinin in this organism. Using the pI and molecularmass 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.
Afficher plus [+] Moins [-]An immunohistochemical study of ovarian innervation in the emu (<i>Dromaius novaehollandiae</i>) Texte intégral
2008
M.C. Madekurozwa
The present study investigated the distribution of nerves in the ovary of the emu. The neuronal markers, protein gene product 9.5, neurofilament protein and neuron specific enolase demonstrated the constituents of the extrinsic and intrinsic ovarian neural systems. The extrinsic neural system was composed of ganglia in the ovarian stalk, as well as nerve bundles, which were distributed throughout the ovary. Isolated neuronal cell bodies, in the medulla and cortex, formed the intrinsic neural system. An interesting finding of the study was the presence of nerve bundles, circumscribed by lymphocytes, in the ovarian stalk. The findings of the study indicate that the distribution of nerve fibres and neuronal cell bodies in the emu ovary is similar, but not identical to that of the domestic fowl and ostrich.
Afficher plus [+] Moins [-]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 Texte intégral
2008
A.F. Vatta | R.C. Krecek | R.A. Pearson | M.F. Smith | M.O. Stenson | E.F. Van Wijk | L.J.S. Harrison
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 Texte intégral
2008
A.F. Vatta | R.C. Krecek | R.A. Pearson | M.F. Smith | M.O. Stenson | E.F. Van Wijk | L.J.S. Harrison
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 lo
Afficher plus [+] Moins [-]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 Texte intégral
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.
Afficher plus [+] Moins [-]Experimental infections of baboons (<i>Papio</i> spp.) and vervet monkeys (<i>Cercopithecus aethiops</i>) with <i>Trichinella zimbabwensis</i> and successful treatment with ivermectin Texte intégral
2008
S. Mukaratirwa | B. M. Dzoma | E. Matenga | S. D. Ruziwa | L. Sacchi | E. Pozio
Experimental Trichinella zimbabwensis infections were established in three baboons (Papios p.)and four vervet monkeys (Cercopithecuase thiops) and the clinical-pathological manifestations assessed. The infected animals showed clinical signs ranging from fever, diarrhoea, periorbitaol edema and muscular pain in varying degrees. One baboon became blind due to the infection. Levels of creatinine phosphokinase and lactated ehydrogenase increased to reach a peak on Day 42 post-infection(pi)for both baboons and monkeys. Blood parameters such as packed cell volume, levels of red blood cells and white blood cells did not change significantly from the normal ranges except for the levels of eosinophils which peaked above the normal ranges at Day 28 and 56 pi in baboons and at Day 56 pi in monkeys.
Afficher plus [+] Moins [-]The helminth community of Helmeted Guineafowls, <i>Numida meleagris</i> (Linnaeus, 1758), in the north of Limpopo Province, South Africa Texte intégral
2008
K. Junker | L. Debusho | J. Boomker
The helminths of 15 Helmeted Guineafowls were collected in the north of Limpopo Province, South Africa. A total of 11 cestode, ten nematode and a single acanthocephalan species were present. Species richness ranged from 8 to 16 species per host, and nine core and nine secondary species accounted for 40.9% of the component parasite community. The remaining 18.2% comprised satellite species. Core species represented 91% of all the worms present. Individual intensities ranged from 66 to 2 724 per host and overdispersion was pronounced. There were no significant differences regarding the abundance and species richness between male and female hosts. The number of component species and overall abundance did not differ significantly between juvenile and adult hosts, but Cyrnea parroti was significantly more abundant, and the prevalence of Hadjelia truncata was higher in young birds than in adults. In contrast, Gongylonema congolense and Porogynia paronai were absent in juveniles, but had a prevalence of 60% and 70%, respectively, in adults. Pairwise Spearman's rank correlation yielded one positive and 10 negative significant species correlations. A single trematode, Dicrocoelium macrostomum, was collected from five of nine guineafowls, but was not included in the helminth community study.
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