National Veterinary Institute NVI
National Veterinary Institute NVI
Bitew M.,National Veterinary Institute NVI |
Nandi S.,Indian Veterinary Research Institute |
Ravishankar C.,Indian Veterinary Research Institute |
Sharma A.,Indian Veterinary Research Institute
International Journal of Virology | Year: 2017
Background: Recent invasion of multiple bluetongue virus serotypes (BTV) in different regions of the world necessitates urgent development of efficient vaccine that aims numerous serotypes. Materials and Methods: In this experimental study, humoral immune response and protective efficacy of binary ethylenimine (BEI) inactivated montanide adjuvanted pentavalent (BTV 1, 2, 10, 16 and 23) vaccine was evaluated in sheep against challenge with homologous serotypes in their respective group. Results: All sheep were seronegative at day 0 before vaccination. After first vaccination, mean PI value was gradually declined in all vaccinated sheep. Vaccinated sheep were seroconverted to bluetongue virus starting from 10 days of primary vaccination (DPV) with Mean±SD PI value of 36.05±10.78 and log10 Mean±SD neutralizing antibody slightly increased from 0.85-1.42 starting from 3-21 days of post primary vaccination while, unvaccinated group of sheep had Mean±SD PI value of 111.79±12.36 and no log10 serum neutralizing antibody at this point of time. At 28 Days Post Vaccination (DPV), all vaccinated animals registered an abrupt increment in antibody level. Strong seropositivity was remained up to the date of 49 DPV steadily in all vaccinated sheep. After challenge at 49 DPV, vaccinated sheep registered high level of group specific antibody and neutralizing antibody. This level persisted up to 180 days and declined slowly to 270 days post vaccination whereas, unvaccinated challenged showed seropositivity between 7-14 DPC which started to decline after 21 DPC. Increased level of rectal temperature (Mean = 40.8°C) and clinical signs were evident between 5-13 days post challenge in control animals. There was significant difference (p<0.05) between vaccinated and unvaccinated animals in the Mean±SD PI value, log10 Mean±SD of neutralizing antibody, mean rectal temperature and development of clinical signs after homologues virus challenge. However, there was no significant difference (p>0.05) in all above parameters due to variability of challenge virus serotypes. Conclusion: All the findings, clearly suggested that binary ethylenimine (BEI) inactivated montanide adjuvanted pentavalent bluetongue vaccine was effective in protecting sheep from BTV 1, 2, 10, 16 and 23 infections. © 2017 Molalegne Bitew et al.
Ortiz-Pelaez A.,Pinner |
Ashenafi G.,National Veterinary Institute NVI |
Roger F.,CIRAD - Agricultural Research for Development |
Waret-Szkuta A.,CIRAD - Agricultural Research for Development |
Waret-Szkuta A.,Royal Veterinary College
PLoS ONE | Year: 2012
Proximity and affiliation to the local market appear to be two of the most relevant factors to explain farmer's choices to select a particular trading point. Physical barriers may limit the options, especially in developing countries. A network of villages linked by traders/farmer-traders sharing livestock markets was built with field data collected in 75 villages from 8 kebelles in the Wassona Werna wereda of the Ethiopian Highlands. Two exponential random graph models were fitted with various geographical and demographic attributes of the nodes (dyadic independent model) and three internal network structures (dyadic dependent model). Several diagnostic methods were applied to assess the goodness of fit of the models. The odds of an edge where the distance to the main market Debre Behran and the difference in altitude between two connected villages are both large increases significantly so that villages far away from the main market and at different altitude are more likely to be linked in the network than randomly. The odds of forming an edge between two villages in Abamote or Gudoberet kebelles are approximately 75% lower than an edge between villages in any other kebelles (p<0.05). The conditional log-odds of two villages forming a tie that is not included in a triangle, a 2-star or a 3-star is extremely low, increasing the odds significantly (p<0.05) each time a node is in a 2-star structure and decreasing it when a node is in a 3-star (p<0.05) or in a triangle formation (p<0.05)), conditional on the rest of the network. Two major constraining factors, namely distance and altitude, are not deterrent for the potential contact of susceptible small ruminant populations in the Highlands of Ethiopia. © 2012 Ortiz-Pelaez et al.
Aspenstrom-Fagerlund B.,National Food Agency NFA |
Nordkvist E.,National Veterinary Institute NVI |
Tornkvist A.,NFA |
Wallgren P.,NVI, Inc. |
And 3 more authors.
Food Additives and Contaminants - Part A Chemistry, Analysis, Control, Exposure and Risk Assessment | Year: 2016
Toxic effects of chloramphenicol in humans caused the ban for its use in food-producing animals in the EU. A minimum required performance level (MRPL) was specified for chloramphenicol at 0.3 μg kg–1 for various matrices, including urine. In 2012, residues of chloramphenicol were found in pig urine and muscle without signs of illegal use. Regarding its natural occurrence in straw, it was hypothesised that this might be the source, straw being compulsory for use as bedding material for pigs in Sweden. Therefore, we investigated if low daily doses of chloramphenicol (4, 40 and 400 μg/pig) given orally during 14 days could result in residues in pig tissues and urine. A dose-related increase of residues was found in muscle, plasma, kidney and urine (showing the highest levels), but no chloramphenicol was found in the liver. At the lowest dose, residues were below the MRPL in all tissues except in the urine. However, in the middle dose, residues were above the MRPL in all tissues except muscle, and at the highest dose in all matrices. This study proves that exposure of pigs to chloramphenicol in doses occurring naturally in straw could result in residues above the MRPL in plasma, kidney and especially urine. © 2016 Informa UK Limited, trading as Taylor & Francis Group.
Silva A.C.,Institute Biologia Experimental e Tecnologica IBET |
Silva A.C.,University of Lisbon |
Yami M.,National Veterinary Institute NVI |
Libeau G.,CIRAD - Agricultural Research for Development |
And 4 more authors.
Vaccine | Year: 2014
In this paper extended tests on a new candidate formulation for Peste des Petits Ruminants (PPR) vaccine carried out at National Veterinary Institute (NVI) in Ethiopia are presented. This work was performed in the frame of the VACNADA project from GALVmed which aimed at procuring vaccines against neglected veterinary diseases to African vaccine producing laboratories, in particular PPR.After the eradication of Rinderpest, Peste des Petits Ruminants became the next veterinary disease on target for elimination, requiring an effective and thermostable vaccine. In this work a Tris/Trehalose formulation was evaluated in thermal stability studies in comparison to the current used formulation of the live attenuated PPR vaccine, the Weybridge medium. The extended results presented herein show an increased thermal stability of the vaccine, especially at 37 and 45. °C, as expected from previously published results (Silva A.C. et al., 2011). Furthermore, during the course of this project, the NVI teams have clearly demonstrated ability to produce higher quality PPR vaccines after a successful transfer of the technology. These results should significantly enhance the utility of the vaccine in the eradication of PPR. © 2014 Elsevier Ltd.
Gari G.,National Animal Health Diagnostic and Investigation Center |
Abie G.,National Animal Health Diagnostic and Investigation Center |
Gizaw D.,National Animal Health Diagnostic and Investigation Center |
Wubete A.,National Animal Health Diagnostic and Investigation Center |
And 7 more authors.
Vaccine | Year: 2015
The safety, immunogenicity and efficacy of three commercially available vaccines against lumpy skin disease (LSD) in cattle have been evaluated using a combination of vaccine challenge experiments and the monitoring of immune responses in vaccinated animals in the field. The three vaccines evaluated in the study included two locally produced (Ethiopian) vaccines (lumpy skin disease virus (LSDV) Neethling and Kenyan sheep and goat pox (KSGP) O-180 strain vaccines) and a Gorgan goat pox (GTP) vaccine manufactured by Jordan Bio-Industries Centre (JOVAC). The latter vaccine was evaluated for the first time in cattle against LSDV. The Ethiopian Neethling and KSGPO-180 vaccines failed to provide protection in cattle against LSDV, whereas the Gorgan GTP vaccine protected all the vaccinated calves from clinical signs of LSD. There was no significant difference in protective efficacy detected between two dosage levels (P= 0.2, P= 0.25, and P= 0.1 for KSGP, Neethling and Gorgan vaccines, respectively). Additionally, the Gorgan GTP vaccinated cattle showed stronger levels of cellular immune responses measured using Delayed-Type Hypersensitivity (DTH) reactions at the vaccination site indicating higher levels of immunogenicity produced by the GTPV vaccine in cattle, as opposed to the other two vaccines. This study indicated, for the first time, that the Gorgan GTP vaccine can effectively protect cattle against LSDV and that the Neethling and KSGP O-180 vaccine were not protective. The results emphasise the need for molecular characterization of the Neethling and KSGP O-180 vaccine seed viruses used for vaccine production in Ethiopia. In addition, the potency and efficacy testing process of the Ethiopian LSD Neethling and KSGP O-180 vaccines should be re-evaluated. © 2015 Elsevier Ltd.
Sanden M.,National Institute of Nutrition And Seafood Research |
Johannessen L.E.,National Veterinary Institute NVI |
Berdal K.G.,National Veterinary Institute NVI |
Sissener N.,National Institute of Nutrition And Seafood Research |
Hemre G.-I.,National Institute of Nutrition And Seafood Research
Aquaculture Nutrition | Year: 2011
The aim of this study was to examine the presence or absence of dietary transgenic (Roundup Ready ® soybean - RRS ®) and soybean DNA (sRubisco) in the intestinal tract of Atlantic salmon fed either genetically modified (GM) or conventional (non-GM) soybeans. Uptake of dietary DNA was evaluated in the post gastric intestine (pyloric ceca - PC, mid intestine - MI and distal intestine - DI) after continuous feeding (6months), feed restriction and re-feeding using qPCR and in situ hybridization. No transgenic DNA fragments were detected in any of the intestinal samples using event specific primers. Soybean DNA was detected in all segments of the intestinal tissue (PC, MI and DI) and visualized in the cell vacuolar system of the DI in the apex area of the intestinal fold. Dietary DNA was gradually cleared from the intestinal tissues when feed was restricted and could not be detected after 5days. Re-feeding resulted in dietary plant DNA uptake after 2h. The results show that the salmon intestine is able to take up dietary plant DNA shortly after feed intake and that one of the factors affecting uptake and clearance of nucleic acids in the various intestinal segments are the feeding status of the fish. © 2011 Blackwell Publishing Ltd.
Bayissa B.,Addis Ababa Institute of Technology |
Ayelet G.,National Veterinary Institute NVI |
Kyule M.,Addis Ababa Institute of Technology |
Jibril Y.,Addis Ababa Institute of Technology |
Gelaye E.,National Veterinary Institute NVI
Tropical Animal Health and Production | Year: 2011
Cross-sectional serological study and questionnaire survey were conducted in Borana pastoral and agro-pastoral area to determine seroprevalence and risk factors associated with foot-and-mouth disease (FMD) infection and to assess community perceptions as to importance of the disease. A multistage random sampling was carried out to select cattle for seroprevalence and households for interviews. Totally, 768 sera were collected from 111 herds. The overall individual level seroprevalence of 23.0% (n=177) and herd level seroprevalence of 58.6% (n=65) were recorded using 3ABC ELISA test. The variation of individual level seroprevalence in districts were statistically significant (P < 0.05) which was 29.9% in Arero, 24.0% in Yabello, and 15.7% in Teltele. From multivariate logistic regression analysis, herd size and age were seen to be significantly (P < 0.05) associated with FMD seroprevalence. The result of the questionnaire survey based on 120 respondents indicated that, the daily milk yield of cows infected with FMD during outbreaks is reduced to an average of 0.5 L for 25.5 days while cows developing heat-intolerance syndrome after acute infection gave an average 0.67 L for 3.8 months and their calving interval prolonged about 12 months. The questionnaire survey in agro-pastoral area of Borena also indicated that FMD-infected oxen remained off-plough for one season when outbreaks occur in cropping time, whereas heat-intolerant oxen were no longer used for traction. These findings of the present study indicated that FMD is a highly prevalent and economically important disease in the Borana pastoral and agro-pastoral production systems which need effective control strategy for the disease. © 2011 Springer Science+Business Media B.V.
PubMed | International Atomic Energy Agency, Addis Ababa Institute of Technology and National Veterinary Institute NVI
Type: | Journal: Tropical animal health and production | Year: 2016
Mareks disease (MD) is a lymphoproliferative and neuropathic disease of domestic chickens and less commonly, turkeys and quails, caused by a highly contagious, cell-associated, oncogenic herpesvirus. In Ethiopia, MD is believed to be introduced with importation of exotic and crossbred to improve the poultry production and has been reported to be a potential threat to the poultry sector both in backyard and commercial farming systems. This study was aimed at isolation and molecular analysis of MD virus isolates circulating in chicken population in the central part of Ethiopia where commercial farms are populated. From September 2013 to January 2014, clinical and post-mortem examination were conducted on diseased chickens suspected of MD virus infection. Representative spleen and feather follicle samples were collected following sterile procedure, and infectious virus isolation was performed using primary chicken fibroblast cell culture. Cell culture inoculated with suspension of pathological samples developed characteristic MD virus cytopathic effect of rounding of the cells and small plaques. Further analysis of the virus was conducted by conventional PCR amplifying the ICP4 gene fragment from eleven tissue samples using MD virus specific primers. PCR products were further sequenced and analyzed. Nucleotide sequence similarity search of the local isolates resulted a high degree of sequence similarity with Gallid Herpes virus type 2 strain (Mareks disease virus type 1, JN034558). To our knowledge, the present study is the first report conducted on virus isolation and molecular characterization of MD virus isolates circulated in Ethiopia. Eleven ICP4-like gene fragment (318bp) sequences generated in the present study were uploaded in the public database (KU842366-76). Further research on virus isolation, genetic characterization, and infection dynamics is recommended targeting chickens of all age groups reared in different agro-ecological zones under different production system.
PubMed | University of the West Indies, National Animal Health Diagnostic and Investigation Center, CIRAD - Agricultural Research for Development, The Pirbright Institute and National Veterinary Institute NVI
Type: Journal Article | Journal: Vaccine | Year: 2015
The safety, immunogenicity and efficacy of three commercially available vaccines against lumpy skin disease (LSD) in cattle have been evaluated using a combination of vaccine challenge experiments and the monitoring of immune responses in vaccinated animals in the field. The three vaccines evaluated in the study included two locally produced (Ethiopian) vaccines (lumpy skin disease virus (LSDV) Neethling and Kenyan sheep and goat pox (KSGP) O-180 strain vaccines) and a Gorgan goat pox (GTP) vaccine manufactured by Jordan Bio-Industries Centre (JOVAC). The latter vaccine was evaluated for the first time in cattle against LSDV. The Ethiopian Neethling and KSGPO-180 vaccines failed to provide protection in cattle against LSDV, whereas the Gorgan GTP vaccine protected all the vaccinated calves from clinical signs of LSD. There was no significant difference in protective efficacy detected between two dosage levels (P=0.2, P=0.25, and P=0.1 for KSGP, Neethling and Gorgan vaccines, respectively). Additionally, the Gorgan GTP vaccinated cattle showed stronger levels of cellular immune responses measured using Delayed-Type Hypersensitivity (DTH) reactions at the vaccination site indicating higher levels of immunogenicity produced by the GTPV vaccine in cattle, as opposed to the other two vaccines. This study indicated, for the first time, that the Gorgan GTP vaccine can effectively protect cattle against LSDV and that the Neethling and KSGP O-180 vaccine were not protective. The results emphasise the need for molecular characterization of the Neethling and KSGP O-180 vaccine seed viruses used for vaccine production in Ethiopia. In addition, the potency and efficacy testing process of the Ethiopian LSD Neethling and KSGP O-180 vaccines should be re-evaluated.