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Sutcliffe O.B.,University of Strathclyde | Sutcliffe O.B.,Manchester Metropolitan University | Skellern G.G.,University of Strathclyde | Araya F.,University of Strathclyde | And 6 more authors.
OIE Revue Scientifique et Technique | Year: 2014

African animal trypanosomosis is arguably the most important animal disease impairing livestock agricultural development in sub-Saharan Africa. In addition to vector control, the use of trypanocidal drugs is important in controlling the impact of the disease on animal health and production in most sub-Saharan countries. However, there are no internationally agreed standards (pharmacopoeia-type monographs or documented product specifications) for the quality control of these compounds. This means that it is impossible to establish independent quality control and quality assurance standards for these agents. An international alliance between the Food and Agriculture Organization of the United Nations, the International Federation for Animal Health, the Global Alliance for Livestock Veterinary Medicines, the University of Strathclyde and the International Atomic Energy Agency (with critical support from the World Organisation for Animal Health) was established to develop quality control and quality assurance standards fortrypanocidal drugs, with the aim of transferring these methodologies to two control laboratories in sub-Saharan Africa that will serve as reference institutions for their respective regions. The work of the international alliance will allow development of control measures against sub-standard or counterfeit trypanocidal drugs for treatment of trypanosome infection. Monographs on diminazene aceturate (synonym: diminazene diaceturate), isometamidium chloride hydrochloride, homidium chloride and bromide salts and their relevant veterinary formulations for these agents are given in the annex to this paper. However, the authors do not recommend use of homidium bromide and chloride, because of their proven mutagenic properties in some animal test models and their suspected carcinogenic properties.


Njenga M.K.,Centers for Disease Control and Prevention | Njenga M.K.,Washington State University | Njagi L.,Kenya Ministry of Agriculture Livestock and Fisheries | Thumbi S.M.,Washington State University | And 11 more authors.
PLoS Neglected Tropical Diseases | Year: 2015

Background: Although livestock vaccination is effective in preventing Rift Valley fever (RVF) epidemics, there are concerns about safety and effectiveness of the only commercially available RVF Smithburn vaccine. We conducted a randomized controlled field trial to evaluate the immunogenicity and safety of the new RVF Clone 13 vaccine, recently registered in South Africa. Methods: In a blinded randomized controlled field trial, 404 animals (85 cattle, 168 sheep, and 151 goats) in three farms in Kenya were divided into three groups. Group A included males and non-pregnant females that were randomized and assigned to two groups; one vaccinated with RVF Clone 13 and the other given placebo. Groups B included animals in 1st half of pregnancy, and group C animals in 2nd half of pregnancy, which were also randomized and either vaccinated and given placebo. Animals were monitored for one year and virus antibodies titers assessed on days 14, 28, 56, 183 and 365. Results: In vaccinated goats (N = 72), 72% developed anti-RVF virus IgM antibodies and 97% neutralizing IgG antibodies. In vaccinated sheep (N = 77), 84% developed IgM and 91% neutralizing IgG antibodies. Vaccinated cattle (N = 42) did not develop IgM antibodies but 67% developed neutralizing IgG antibodies. At day 14 post-vaccination, the odds of being seropositive for IgG in the vaccine group was 3.6 (95% CI, 1.5 – 9.2) in cattle, 90.0 (95% CI, 25.1 – 579.2) in goats, and 40.0 (95% CI, 16.5 – 110.5) in sheep. Abortion was observed in one vaccinated goat but histopathologic analysis did not indicate RVF virus infection. There was no evidence of teratogenicity in vaccinated or placebo animals. Conclusions: The results suggest RVF Clone 13 vaccine is safe to use and has high (>90%) immunogenicity in sheep and goats but moderate (> 65%) immunogenicity in cattle. © 2015 Njenga et al.


PubMed | Centers for Disease Control and Prevention, Global Alliance for Livestock Veterinary Medicines, South African National Institute for Communicable Diseases, Washington State University and Kenya Ministry of Agriculture Livestock and Fisheries
Type: Journal Article | Journal: PLoS neglected tropical diseases | Year: 2015

Although livestock vaccination is effective in preventing Rift Valley fever (RVF) epidemics, there are concerns about safety and effectiveness of the only commercially available RVF Smithburn vaccine. We conducted a randomized controlled field trial to evaluate the immunogenicity and safety of the new RVF Clone 13 vaccine, recently registered in South Africa.In a blinded randomized controlled field trial, 404 animals (85 cattle, 168 sheep, and 151 goats) in three farms in Kenya were divided into three groups. Group A included males and non-pregnant females that were randomized and assigned to two groups; one vaccinated with RVF Clone 13 and the other given placebo. Groups B included animals in 1st half of pregnancy, and group C animals in 2nd half of pregnancy, which were also randomized and either vaccinated and given placebo. Animals were monitored for one year and virus antibodies titers assessed on days 14, 28, 56, 183 and 365.In vaccinated goats (N = 72), 72% developed anti-RVF virus IgM antibodies and 97% neutralizing IgG antibodies. In vaccinated sheep (N = 77), 84% developed IgM and 91% neutralizing IgG antibodies. Vaccinated cattle (N = 42) did not develop IgM antibodies but 67% developed neutralizing IgG antibodies. At day 14 post-vaccination, the odds of being seropositive for IgG in the vaccine group was 3.6 (95% CI, 1.5 - 9.2) in cattle, 90.0 (95% CI, 25.1 - 579.2) in goats, and 40.0 (95% CI, 16.5 - 110.5) in sheep. Abortion was observed in one vaccinated goat but histopathologic analysis did not indicate RVF virus infection. There was no evidence of teratogenicity in vaccinated or placebo animals.The results suggest RVF Clone 13 vaccine is safe to use and has high (>90%) immunogenicity in sheep and goats but moderate (> 65%) immunogenicity in cattle.


Moreno L.,CONICET | Lopez-Urbina M.T.,National Major San Marcos University | Lopez-Urbina M.T.,Cysticercosis Working Group | Farias C.,CONICET | And 11 more authors.
Food and Chemical Toxicology | Year: 2012

Oxfendazole (OFZ) is efficacious for porcine cysticercosis at 30mg/kg. OFZ is not registered to be used at this dose. The assessment of the OFZ and metabolites [(fenbendazole sulphone (FBZSO2), fenbendazole (FBZ)] plasma pharmacokinetic and tissue residue profiles after its oral administration to pigs and the withdrawal period for human consumption were reported. Forty-eight pigs allocated into two groups received OFZ (30mg/kg) orally as a commercial (CF) or as experimental formulation (SMF). Samples (blood, muscle, liver, kidney and fat) were collected over 30days post-treatment and analyzed by HPLC. OFZ was the main compound recovered in plasma, followed by FBZSO2 and low FBZ concentrations. OFZ AUC0-LOQ (209.9±33.9μg·h/ml) and Cmax (5.40±0.65μg/ml) parameters for the CF tended to be higher than those for the SMF (AUC0-LOQ: 159.4±18.3μgh/ml, Cmax: 3.80±0.35μg/ml). The highest total residue (OFZ+FBZSO2+FBZ) concentrations were quantified in liver, followed by kidney, muscle and fat tissue. FBZSO2 residue levels were the highest found in muscle (0.68±0.39μg/g) and fat (0.69±0.39μg/g). In liver and kidney the highest residues corresponded to FBZ (5.29±4.36μg/g) and OFZ (2.86±0.75μg/g), respectively. A withdrawal time of 17days post-treatment was established before tissues are delivered for human consumption. © 2012 Elsevier Ltd.


Peters A.R.,Global Alliance for Livestock Veterinary Medicines | Domingue G.,Global Alliance for Livestock Veterinary Medicines | Olorunshola I.D.,Global Alliance for Livestock Veterinary Medicines | Thevasagayam S.J.,Global Alliance for Livestock Veterinary Medicines | And 3 more authors.
Livestock Research for Rural Development | Year: 2012

A total of 558 farmers were interviewed in the districts of Kakamega and Machakos in Kenya during 2007-08 regarding their family circumstances and agricultural activities. Approximately 60% were in the age range 20 to 49 while almost 40% were more than 49 years old and 60% of respondents were females. They had spent a variable length of time in farming from <10 to more than 40 years. The average size of farm holding was between 0.4 and 2.0 hectares and almost all respondents were involved in mixed farming (crops and livestock). Livestock species discussed included poultry, cattle and small ruminants and were kept in a range of combinations. Most poultry keepers had between 1 and 20 chickens. Crops included maize, beans and cowpeas and a range of others including horticultural activities. Most farms had to provide supplementary feed to livestock which included hay, napier grass and maize stalks for ruminants and flour residue, maize and commercial feeds for poultry. Respondents used eggs and poultry meat for domestic consumption and surpluses were sold either from the house or at market, sometimes involving an intermediate trader. Additional income from produce sales was used to purchase domestic items including food and fuel.


Peters A.R.,Global Alliance for Livestock Veterinary Medicines | Domingue G.,Global Alliance for Livestock Veterinary Medicines | Olorunshola I.D.,Global Alliance for Livestock Veterinary Medicines | Thevasagayam S.J.,Global Alliance for Livestock Veterinary Medicines | And 3 more authors.
Livestock Research for Rural Development | Year: 2012

A total of 558 farmers were interviewed in the counties of Kakamega and Machakos in Kenya during 2007-08 regarding their attitudes and practices relating to livestock diseases and their recognition and management. Most respondents regarded East Coast fever (ECF), contagious caprine pleuropneumonia (CCPP) and Newcastle Disease (ND) as the most important diseases of cattle, small ruminants and chickens, respectively. There was a high degree of awareness and past use of vaccines and treatments for a number of cattle diseases and these activities were most likely to be carried out by a veterinarian. There was less use of vaccines in small ruminants and chickens but disease treatments were commonly used. Poultry vaccines were purchased from veterinarians and from agrovet shops. Less than half the respondents believed vaccines to be effective but few reported suspected ineffective vaccinations to a veterinary officer. Most respondents (Kakamega only) were willing to pay up to 5Ksh, 10Ksh and 20Ksh for chicken, small ruminant and cattle vaccines, respectively. Respondents preferred the administration of poultry vaccines to be via drinking water and most preferred vaccination on an individual farm basis rather than group vaccination activities. Almost all the respondents expressed the need for training in poultry vaccination. Respondents expressed a preference for vaccine pack sizes of less than 50 doses and for the availability of thermo-tolerant vaccines.


Fleming J.R.,University of Dundee | Sastry L.,University of Dundee | Crozier T.W.M.,University of Dundee | Napier G.B.,Global Alliance for Livestock Veterinary Medicines | And 2 more authors.
PLoS Neglected Tropical Diseases | Year: 2014

Animal African Trypanosomosis (AAT) presents a severe problem for agricultural development in sub-Saharan Africa. It is caused by several trypanosome species and current means of diagnosis are expensive and impractical for field use. Our aim was to discover antigens for the detection of antibodies to Trypanosoma congolense, one of the main causative agents of AAT. We took a proteomic approach to identify potential immunodiagnostic parasite protein antigens. One hundred and thirteen proteins were identified which were selectively recognized by infected cattle sera. These were assessed for likelihood of recombinant protein expression in E. coli and fifteen were successfully expressed and assessed for their immunodiagnostic potential by ELISA using pooled pre- and post-infection cattle sera. Three proteins, members of the invariant surface glycoprotein (ISG) family, performed favorably and were then assessed using individual cattle sera. One antigen, Tc38630, evaluated blind with 77 randomized cattle sera in an ELISA assay gave sensitivity and specificity performances of 87.2% and 97.4%, respectively. Cattle immunoreactivity to this antigen diminished significantly following drug-cure, a feature helpful for monitoring the efficacy of drug treatment. © 2014 Fleming et al.


PubMed | Global Alliance for Livestock Veterinary Medicines and University of Dundee
Type: Evaluation Studies | Journal: PLoS neglected tropical diseases | Year: 2014

Animal African Trypanosomosis (AAT) presents a severe problem for agricultural development in sub-Saharan Africa. It is caused by several trypanosome species and current means of diagnosis are expensive and impractical for field use. Our aim was to discover antigens for the detection of antibodies to Trypanosoma congolense, one of the main causative agents of AAT. We took a proteomic approach to identify potential immunodiagnostic parasite protein antigens. One hundred and thirteen proteins were identified which were selectively recognized by infected cattle sera. These were assessed for likelihood of recombinant protein expression in E. coli and fifteen were successfully expressed and assessed for their immunodiagnostic potential by ELISA using pooled pre- and post-infection cattle sera. Three proteins, members of the invariant surface glycoprotein (ISG) family, performed favorably and were then assessed using individual cattle sera. One antigen, Tc38630, evaluated blind with 77 randomized cattle sera in an ELISA assay gave sensitivity and specificity performances of 87.2% and 97.4%, respectively. Cattle immunoreactivity to this antigen diminished significantly following drug-cure, a feature helpful for monitoring the efficacy of drug treatment.

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