The Onderstepoort journal of veterinary research, 2000
During 1995/1996 parts of South Africa experienced exceptionally high rainfall. Large numbers of ... more During 1995/1996 parts of South Africa experienced exceptionally high rainfall. Large numbers of Culicoides midges were seen and an outbreak of African horsesickness (AHS) followed. In the Onderstepoort area, near Pretoria in Gauteng, a number of horses died of suspected AHS. Virus isolation and typing was done from blood and/or organ samples of 21 suspected cases as well as from five zebra which were kept in the area. Virus was isolated from 14 of the 21 suspected cases but not from the zebra. The neutralizing antibody response of the zebra to the nine different African horsesickness virus (AHSV) serotypes was determined. Results indicated the highest prevalence of serotypes 2 and 4 followed by serotypes 1, 6 and 9. Reverse transcription polymerase chain reaction (RT-PCR) was performed on total RNA extracted from blood samples of the zebra. AHSV RNA was indicated in three of five zebra by agarose gel electrophoresis analysis of amplicons and in four of five zebra after Southern blo...
Abstract: An attenuated live bluetongue virus (AL-BTV) serotype 8 vaccine of South African origin... more Abstract: An attenuated live bluetongue virus (AL-BTV) serotype 8 vaccine of South African origin was evaluated for its ability to protect sheep against challenge with a European BTV-8 isolated from an outbreak. Two groups of sero-negative sheep were vaccinated with either a single or booster vaccination and challenged subcutaneously 28 days following vaccination. Groups of vaccinated challenged sheep showed no clinical signs typical to Bluetongue disease, as compared to unvacci-nated inoculated sheep of a control group. A clinical reaction index (CRI) of values ranging from 0 to 5 was determined for each of the groups, where vaccinates measured a CRI of less than 1 and the control sheep measured a CRI of at least 4.5. All vaccinated sheep developed high serotype-specific neutralizing antibodies post-vaccination. The results indicated that a single dose of the AL-BTV-8 was sufficient to protect vaccinated sheep against a virulent challenge of the European BTV-8 outbreak isolate.
The Onderstepoort journal of veterinary research, 2000
During 1995/1996 parts of South Africa experienced exceptionally high rainfall. Large numbers of ... more During 1995/1996 parts of South Africa experienced exceptionally high rainfall. Large numbers of Culicoides midges were seen and an outbreak of African horsesickness (AHS) followed. In the Onderstepoort area, near Pretoria in Gauteng, a number of horses died of suspected AHS. Virus isolation and typing was done from blood and/or organ samples of 21 suspected cases as well as from five zebra which were kept in the area. Virus was isolated from 14 of the 21 suspected cases but not from the zebra. The neutralizing antibody response of the zebra to the nine different African horsesickness virus (AHSV) serotypes was determined. Results indicated the highest prevalence of serotypes 2 and 4 followed by serotypes 1, 6 and 9. Reverse transcription polymerase chain reaction (RT-PCR) was performed on total RNA extracted from blood samples of the zebra. AHSV RNA was indicated in three of five zebra by agarose gel electrophoresis analysis of amplicons and in four of five zebra after Southern blo...
Abstract: An attenuated live bluetongue virus (AL-BTV) serotype 8 vaccine of South African origin... more Abstract: An attenuated live bluetongue virus (AL-BTV) serotype 8 vaccine of South African origin was evaluated for its ability to protect sheep against challenge with a European BTV-8 isolated from an outbreak. Two groups of sero-negative sheep were vaccinated with either a single or booster vaccination and challenged subcutaneously 28 days following vaccination. Groups of vaccinated challenged sheep showed no clinical signs typical to Bluetongue disease, as compared to unvacci-nated inoculated sheep of a control group. A clinical reaction index (CRI) of values ranging from 0 to 5 was determined for each of the groups, where vaccinates measured a CRI of less than 1 and the control sheep measured a CRI of at least 4.5. All vaccinated sheep developed high serotype-specific neutralizing antibodies post-vaccination. The results indicated that a single dose of the AL-BTV-8 was sufficient to protect vaccinated sheep against a virulent challenge of the European BTV-8 outbreak isolate.
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