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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 Texto completo
2008
Vatta, A.F. | Krecek, R.C. | Pearson, R.A. | Smith, M.F. | Stenson, M.O. | Van Wijk, E.F. | Harrison, L.J.S.
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 Texto completo
2008
Vatta, A.F. | Krecek, R.C. | Pearson, R.A. | Smith, M.F. | Stenson, M.O. | Van Wijk, E.F. | Harrison, L.J.S.
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
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 Texto completo
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
Mostrar más [+] Menos [-]Value of tests for evaluating udder health in dairy goats: somatic cell counts, California Milk Cell Test and electrical conductivity Texto completo
2008
Petzer, I.M. | Donkin, E.F. | Du Preez, E. | Karzis, J. | Van der schans, T.J. | Watermeyer, J.C. | Van Reenen, R.
Value of tests for evaluating udder health in dairy goats: somatic cell counts, California Milk Cell Test and electrical conductivity Texto completo
2008
Petzer, I.M. | Donkin, E.F. | Du Preez, E. | Karzis, J. | Van der schans, T.J. | Watermeyer, J.C. | Van Reenen, R.
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).
Mostrar más [+] Menos [-]Value of tests for evaluating udder health in dairy goats: somatic cell counts, California Milk Cell Test and electrical conductivity Texto completo
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).
Mostrar más [+] Menos [-]Bovine intestinal cellular responses following primary and challenge infections with Calicophoron microbothrium metacercariae Texto completo
2008
Mavenyengwa, N. | Mukaratirwa, S. | Obwolo, M. | Monrad, J.
Bovine intestinal cellular responses following primary and challenge infections with Calicophoron microbothrium metacercariae Texto completo
2008
Mavenyengwa, N. | Mukaratirwa, S. | Obwolo, M. | Monrad, J.
This studyw as carried out to establish whether cattle can develop resistance to re-infectionby Calicophoron microbothrium by assessing the response of intestinal mucosal globule leukocytese, osinophils, mast cells and basophils, and the establishment of the parasite in the host. A total of 241-year old Tuli steers were randomly divided into four groups of six animals each and infected with C. microbothriumm etacercariae. On the first day of the study, animals in Groups I and II were immunized with 5000 metacercariae and then challenged with 15000 metacercariae on Day 150 post immunization. Animals in Group III were immunized with 15000 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, duodenuma, bomasum 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.
Mostrar más [+] Menos [-]Bovine intestinal cellular responses following primary and challenge infections with <i>Calicophoron microbothrium</i> metacercariae Texto completo
2008
N. Mavenyengwa | S. Mukaratirwa | M. Obwolo | J. Monrad
This studyw as carried out to establish whether cattle can develop resistance to re-infectionby Calicophoron microbothrium by assessing the response of intestinal mucosal globule leukocytese, osinophils, mast cells and basophils, and the establishment of the parasite in the host. A total of 241-year old Tuli steers were randomly divided into four groups of six animals each and infected with C. microbothriumm etacercariae. On the first day of the study, animals in Groups I and II were immunized with 5000 metacercariae and then challenged with 15000 metacercariae on Day 150 post immunization. Animals in Group III were immunized with 15000 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, duodenuma, bomasum 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.
Mostrar más [+] Menos [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004) Texto completo
2008
Howell, P. G. | Nurton, Jane P. | Nel, Daleen | Lourens, Carina W. | Guthrie, A. J.
Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004) Texto completo
2008
Howell, P. G. | Nurton, Jane P. | Nel, Daleen | Lourens, Carina W. | Guthrie, A. J.
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 [-]Prevalence of serotype specific antibody to equine encephalosis virus in Thoroughbred yearlings South Africa (1999-2004) Texto completo
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 [-]Helminth parasites of Natal long-fingered bats, Miniopterus natalensis (Chiroptera : Miniopteridae), in South Africa : research communication Texto completo
2008
Junker, K. | Bain, O. | Boomker, J.
Helminth parasites of Natal long-fingered bats, Miniopterus natalensis (Chiroptera : Miniopteridae), in South Africa : research communication Texto completo
2008
Junker, K. | Bain, O. | Boomker, J.
The helminth community infecting Miniopterus natalensis was studied at two localities, the De Hoop Nature Reserve (DHNR) (n = 57), Western Cape Province and Pretoria (n = 12), Gauteng Province, South Africa. Hosts from the DHNR had formed part of an earlier, unrelated study and were all pregnant females. A single hymenolepidid cestode species, the nematodes Molinostrongylus ornatus and Litomosa chiropterorum together with nematodes of the subfamily Capillariinae were present at both study sites, while a single digenean, Allassogonoporus sp., was only found in hosts from the DHNR. The prevalence of helminth infections was high at both localities, 68.4 % in the DHNR and 77.7 % in Pretoria, whereas the mean intensity of infection was low at the DHNR (3.76 3.15), but higher in Pretoria (10.4 9.9). Molinostrongylus ornatus and, to a lesser extent L. chiropterorum, were the main contributors to the higher intensities in Pretoria. The species richness ranged from 0 to 4 at both localities.
Mostrar más [+] Menos [-]Helminth parasites of Natal long-fingered bats, <i>Miniopterus natalensis</i> (Chiroptera : Miniopteridae), in South Africa : research communication Texto completo
2008
K. Junker | O. Bain | J. Boomker
The helminth community infecting Miniopterus natalensis was studied at two localities, the De Hoop Nature Reserve (DHNR) (n = 57), Western Cape Province and Pretoria (n = 12), Gauteng Province, South Africa. Hosts from the DHNR had formed part of an earlier, unrelated study and were all pregnant females. A single hymenolepidid cestode species, the nematodes Molinostrongylus ornatus and Litomosa chiropterorum together with nematodes of the subfamily Capillariinae were present at both study sites, while a single digenean, Allassogonoporus sp., was only found in hosts from the DHNR. The prevalence of helminth infections was high at both localities, 68.4 % in the DHNR and 77.7 % in Pretoria, whereas the mean intensity of infection was low at the DHNR (3.76 ± 3.15), but higher in Pretoria (10.4 ± 9.9). Molinostrongylus ornatus and, to a lesser extent L. chiropterorum, were the main contributors to the higher intensities in Pretoria. The species richness ranged from 0 to 4 at both localities.
Mostrar más [+] Menos [-]Evaluation of different adjuvants for foot-and-mouth disease vaccine containing all the SAT serotypes Texto completo
2008
Cloete, M. | Dungu, B. | Van Staden, L.I. | Ismail-Cassim, N. | Vosloo, W.
Evaluation of different adjuvants for foot-and-mouth disease vaccine containing all the SAT serotypes Texto completo
2008
Cloete, M. | Dungu, B. | Van Staden, L.I. | Ismail-Cassim, N. | Vosloo, W.
Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals that is primarily controlled by vaccination of susceptible animals and movement restrictions for animals and animal-derived products in South Africa. Vaccination using aluminium hydroxide gel-saponin (AS) adjuvanted vaccines containing the South African Territories (SAT) serotypes has been shown to be effective both in ensuring that disease does not spread from the endemic to the free zone and in controlling outbreaks in the free zone. Various vaccine formulations containing antigens derived from the SAT serotypes were tested in cattle that were challenged 1 year later. Both the AS and ISA 206B vaccines adjuvanted with saponin protected cattle against virulent virus challenge. The oilbased ISA 206B-adjuvanted vaccine with and without stimulators was evaluated in a field trial and both elicited antibody responses that lasted for 1 year. Furthermore, the ISA 206 adjuvanted FMD vaccine protected groups of cattle against homologous virus challenge at very low payloads, while pigs vaccinated with an emergency ISA 206B-based FMD vaccine containing the SAT 1 vaccine strains were protected against the heterologous SAT 1 outbreak strain.
Mostrar más [+] Menos [-]Evaluation of different adjuvants for foot-and-mouth disease vaccine containing all the SAT serotypes Texto completo
2008
M. Cloete | B. Dungu | L.I. Van Staden | N. Ismail-Cassim | W. Vosloo
Foot-and-mouth disease (FMD) is an economically important disease of cloven-hoofed animals that is primarily controlled by vaccination of susceptible animals and movement restrictions for animals and animal-derived products in South Africa. Vaccination using aluminium hydroxide gel-saponin (AS) adjuvanted vaccines containing the South African Territories (SAT) serotypes has been shown to be effective both in ensuring that disease does not spread from the endemic to the free zone and in controlling outbreaks in the free zone. Various vaccine formulations containing antigens derived from the SAT serotypes were tested in cattle that were challenged 1 year later. Both the AS and ISA 206B vaccines adjuvanted with saponin protected cattle against virulent virus challenge. The oilbased ISA 206B-adjuvanted vaccine with and without stimulators was evaluated in a field trial and both elicited antibody responses that lasted for 1 year. Furthermore, the ISA 206 adjuvanted FMD vaccine protected groups of cattle against homologous virus challenge at very low payloads, while pigs vaccinated with an emergency ISA 206B-based FMD vaccine containing the SAT 1 vaccine strains were protected against the heterologous SAT 1 outbreak strain.
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 Texto completo
2008
Du Toit, C.A. | Scholtz, C.H. | Hyman, W.B.
Prevalence of the dog nematode Spirocerca lupi in populations of its intermediate dung beetle host in the Tshwane (Pretoria) Metropole, South Africa Texto completo
2008
Du Toit, C.A. | Scholtz, C.H. | Hyman, W.B.
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 [-]Prevalence of the dog nematode <i>Spirocerca lupi</i> in populations of its intermediate dung beetle host in the Tshwane (Pretoria) Metropole, South Africa Texto completo
2008
C.A. Du Toit | C.H. Scholtz | W.B. Hyman
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 [-]Experimental infections of baboons (Papio spp.) and vervet monkeys (Cercopithecus aethiops) with Trichinella zimbabwensis and successful treatment with ivermectin Texto completo
2008
Mukaratirwa, S. | Dzoma, B. M. | Matenga, E. | Ruziwa, S. D. | Sacchi, L. | Pozio, E.
Experimental infections of baboons (Papio spp.) and vervet monkeys (Cercopithecus aethiops) with Trichinella zimbabwensis and successful treatment with ivermectin Texto completo
2008
Mukaratirwa, S. | Dzoma, B. M. | Matenga, E. | Ruziwa, S. D. | Sacchi, L. | Pozio, E.
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.
Mostrar más [+] Menos [-]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 Texto completo
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.
Mostrar más [+] Menos [-]Molecular characterization of SAT-2 foot-and-mouth disease virus isolates obtained from cattle during a four-month period in 2001 in Limpopo Province, South Africa Texto completo
2008
Phologane, B.S. | Dwarka, R.M. | Haydon, D.T. | Gerber, L.J. | Vosloo, W.
Molecular characterization of SAT-2 foot-and-mouth disease virus isolates obtained from cattle during a four-month period in 2001 in Limpopo Province, South Africa Texto completo
2008
Phologane, B.S. | Dwarka, R.M. | Haydon, D.T. | Gerber, L.J. | Vosloo, W.
Foot-and-mouth disease (FMD) is an acute, highly contagious viral infection of domestic and wild cloven-hoofed animals. The virus is a single-stranded RNA virus that has a high rate of nucleotide mutation and amino acid substitution. In southern Africa the South African Territories (SAT) 1-3 serotypes of FMD virus are maintained by large numbers of African buffaloes (Syncerus caffer), which provide a potential source of infection for domestic livestock and wild animals. During February 2001, an outbreak of SAT-2 was recorded in cattle in the FMD control zone of South Africa, adjacent to the Kruger National Park (KNP). They had not been vaccinated against the disease since they form the buffer between the vaccination and free zones but in the face of the outbreak, they were vaccinated as part of the control measures to contain the disease. The virus was, however, isolated from some of them on several occasions up to May 2001. These isolates were characterized to determine the rate of genetic change in the main antigenic determinant, the 1D/2A gene. Nucleotide substitutions at 12 different sites were identified of which five led to amino acid changes. Three of these occurred in known antigenic sites, viz. the GH-loop and C-terminal part of the protein, and two of these have previously been shown to be subject to positive selection. Likelihood models indicated that the ratio of non-synonymous to synonymous changes among the outbreak sequences recovered from cattle was four times higher than among comparable sequences isolated from wildlife, suggesting that the virus may be under greater selective pressure during rapid transmission events.
Mostrar más [+] Menos [-]Molecular characterization of SAT-2 foot-and-mouth disease virus isolates obtained from cattle during a four-month period in 2001 in Limpopo Province, South Africa Texto completo
2008
B.S. Phologane | R.M. Dwarka | D.T. Haydon | L.J. Gerber | W. Vosloo
Foot-and-mouth disease (FMD) is an acute, highly contagious viral infection of domestic and wild cloven-hoofed animals. The virus is a single-stranded RNA virus that has a high rate of nucleotide mutation and amino acid substitution. In southern Africa the South African Territories (SAT) 1-3 serotypes of FMD virus are maintained by large numbers of African buffaloes (Syncerus caffer), which provide a potential source of infection for domestic livestock and wild animals. During February 2001, an outbreak of SAT-2 was recorded in cattle in the FMD control zone of South Africa, adjacent to the Kruger National Park (KNP). They had not been vaccinated against the disease since they form the buffer between the vaccination and free zones but in the face of the outbreak, they were vaccinated as part of the control measures to contain the disease. The virus was, however, isolated from some of them on several occasions up to May 2001. These isolates were characterized to determine the rate of genetic change in the main antigenic determinant, the 1D/2A gene. Nucleotide substitutions at 12 different sites were identified of which five led to amino acid changes. Three of these occurred in known antigenic sites, viz. the GH-loop and C-terminal part of the protein, and two of these have previously been shown to be subject to positive selection. Likelihood models indicated that the ratio of non-synonymous to synonymous changes among the outbreak sequences recovered from cattle was four times higher than among comparable sequences isolated from wildlife, suggesting that the virus may be under greater selective pressure during rapid transmission events.
Mostrar más [+] Menos [-]2-Phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from Sea World to uShaka Marine World, South Africa Texto completo
2008
Vaughan, D.B. | Penning, M.R. | Christison, K.W.
2-Phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from Sea World to uShaka Marine World, South Africa Texto completo
2008
Vaughan, D.B. | Penning, M.R. | Christison, K.W.
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 mℓ / ℓ and there were no mortalities.
Mostrar más [+] Menos [-]2-phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from sea world to uShaka Marine World, South Africa Texto completo
2008
Vaughan, D.B. | Penning, M.R. | Christison, K.W.
The South African Association for Marine Biological Research, incorporating Sea World, Oceanographic Research Institute and the Dolphinarium relocated from their old premises of 46 years on Durban’s beach front in March and April 2004 to the new Point Development’s marine theme park, uShaka Marine World in Durban, South Africa. Netting of fishes from the large exhibits could cause physical damage to struggling fishes, increasing the risk of opportunistic secondary bacterial infections (Inoue, dos Santos Neto & Morales 2004) which could not be treated in time for the opening of uShaka Marine World on 30 April 2004.
Mostrar más [+] Menos [-]2-Phenoxyethanol as anaesthetic in removing and relocating 102 species of fishes representing 30 families from Sea World to uShaka Marine World, South Africa Texto completo
2008
D.B. Vaughan | M.R. Penning | K.W. Christison
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 mℓ / ℓ and there were no mortalities.
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