Serological screening for Schmallenberg virus in exotic and indigenous cattle in Nigeria

Schmallenberg virus (SBV), a recently emerged Orthobunyavirus, is associated with abortions, stillbirths and congenital malformations in ruminants. Considering that Culicoides species which transmit this disease have previously been identified in Nigeria as vectors of bluetongue, another livestock disease that causes abortions, it is speculated that SBV also circulates in the Nigerian ruminant population. We therefore conducted a pilot study to investigate the occurrence of anti-SBV antibodies in a limited population of cross-breed, exotic and indigenous cattle in Nigeria. Serum samples obtained from 60 Friesian-White Fulani (FWF), 7 Jersey and 53 indigenous cattle were screened for SBV antibodies using a commercial indirect ELISA kit that detects antibodies against recombinant SBV nucleoprotein in ruminant sera. An overall seropositivity of 29.2% (35/120) was obtained with antibodies being detectable in 23.3% FWF (14/60), 42.9% Jerseys (3/7) and 34.0% (18/53) indigenous cattle. All indigenous breeds of cattle tested had seropositive animals: White Fulani (13/38, 34.2%), Sokoto Gudali (2/8, 25.0%), Red Bororo (1/5, 20.0%) and Bunaji (2/2, 100.0%). The detection of antibody-positive animals among unvaccinated cattle provides evidence of possible SBV infection in Nigeria. However, there is also the probability of cross-reactivity with other Simbu serogroup viruses, especially considering that some of these viruses have previously been reported in Nigeria. Further studies to confirm these preliminary findings using serum neutralisation assay, viral isolation or detection of SBV RNA from ruminants or Culicoides are necessary.Keywords: Abortions, Antibodies, Cattle, Congenital malformations, Nigeria, Schmallenberg viru

Serosurvey of antibody to highly pathogenic avian influenza (H5N1) in pigs, north central Nigeria

Avian influenza is a disease of economic and public health importance that has been described in most domestic animals and humans. Highly pathogenic avian influenza H5N1 epidemic in Nigeria was observed in agro-ecological zones where pigs and chickens are raised in shared environment with chances of interspecies transmission. We investigate the likelihood of transmission of the disease to pigs in North Central Nigeria where there were several cases of highly pathogenic avian influenza H5N1 in both commercial and free range poultry. Two hundred and twenty swine sera collected in Kaduna and Plateau states were screened for influenza A/H5N1 antibody by haemagglutination inhibition test according to standard protocol. All the sera tested were negative for influenza A/H5 antibody (HA titre < 22). Our inability to detect appreciable antibody level to avian influenza A/H5N1 therefore may be due to lack of infection because of low susceptibility of pigs to Influenza A/H5N1. We recommend wider serological and virological studies to identify other circulating influenza virus in pigs in different agro-ecological zones to provide useful epidemiological data on evolving influenza virus.&#160

Detection of highly pathogenic avian influenza (H5N1) in apparently healthy ducks (Anas sparsa sparsa) in live bird markets, Nigeria

Nigeria reported the first outbreak of Highly Pathogenic Avian Influenza (HPAI) in Africa, February 2006. Since then effort by relevant authorities to control the spread and persistence of the disease has been effective, with only sporadic resurgence in backyard and live bird markets. Surveillance for HPAI was carried out in live bird markets (LBM) between May and June 2008 in ducks among other species. A total of 4,707samples including sera and swabs of trachea and cloaca from live birds, and parenchymatous organs from dead or moribund birds were collected from 11 states of the country where HPAI has not been previously reported. Tissues were processed for virus isolation in embryonating chicken eggs, sera analyzed by Agar Gel Immuno Diffusion test (AGID) and Haemaglutination Inhibition (HI) tests with standard monoclonal antisera to H5 and the swabs by RT-PCR using gene specific matrix and H5 primers. Two isolates of HPAI were recovered from the tracheal swab samples from apparently healthy ducks

Field Handling and Anti-Rabies Vaccine Efficacy

Anti-rabies vaccine for dogs, earlier procured in 2008 from National Veterinary Research Institute, Vom was received for re-evaluation from the field. The field originated and reference samples of the same production batch (04/2008) were inoculated into 3-week old mice intracerebrally for comparison and observed daily for 21 days. There were no signs of illness, paralysis or death in the groups of mice inoculated with the field vaccine. Whereas deaths were observed between days 7 and 18 post inoculation in the groups inoculated with the reference sample, an indication of live rabies vaccine virus. Animals in the control group remained healthy throughout the periodof observation. This study shows that not all vaccines produced under Good Laboratory Practice and passed are biologically viable following exposure to field conditions due to poor handling and other factors. For efficiency ofimmunization therefore, the quality of anti-rabies vaccine must be ensured by maintaining an effective cold chain on storage between the time of production, procurement and usage in the field

In-ovo evaluation of the antiviral activity of methanolic root-bark extract of the African Baobab (Adansonia digitata Lin)

Application of ethnoveterinary medicine in the control of poultry diseases is being embraced in many parts of the world for more profitable production. This study investigated the antiviral property of the root-bark extract of the African Baobab tree (Adansonia digitata Lin) against Newcastle disease virus. One hundred and seventy five specific antibody negative embryonated chicken eggs and a field strain of Newcastle disease virus were used to test for the antiviral activity of the methanolic root bark extract of the tree. Following a 2-h exposure of the virus to eight graded concentrations of the extract, it was incubated at 37°C and observed 12-hourly for mortality. Dead embryos were spot tested for haemagglutinating activity. The 100EID50 concentration of the virus and the highest concentration of the extract were inoculated as positive and negative controls, respectively. All eggs inoculated with the virus alone as well as 5 and 2 mg/ml extract/virus suspensions, died by 72 h post inoculation, while no mortality was observed amongst those inoculated with 250 and 200 mg/ml virus/extract suspensions as well as those inoculated with the pure extract. Mortalities of 40, 40 and 20%, due to viral activity were recorded for 25, 50 and 100 mg/ml suspensions, respectively. This study showed that methanolic rootbark extract of A. digitata has antiviral activity against Newcastle disease virus in ovo, particularly when used at dose rates of 200 and 250 mg/ml.Key words: Ethnoveterinary, African Baobab, antiviral activity, Newcastle disease virus

Non-Attenuation Of Highly Pathogenic Avian Influenza H5N1 By Laboratory Exposure To Ultraviolet Rays

Avian influenza H5N1 represents one of the most researched viruses in laboratories world-wide in recent times with regards to its epidemiology, ecology, biology and geography. The virus has caused 409 human cases and 256 human fatalities to date. Some laboratory activities and other lab relatedworks predispose certain workers to exposure to this virus. In this work, we assessed the effect of exposure of HPAI infective allantoic fluid to ultraviolet rays for between 15 and 180 minutes. No significant difference was found between the unexposed and exposed viruses. The ability of the virus to haemagglutinate chicken red blood cells, the haemagglutination titre and its pathogenicity in embryonating eggs did not change despite this prolong exposure to UV-light. We call for caution in the handling of HPAI viruses in laboratory inside the microbiological safety cabinet despite sterilization using UV-light

Fusarium graminearum in a Papilloma Virus Infected Friesian Bull in Vom, Nigeria: Case Report

Importation of exotic cattle to improve the yield and productivityof the local 'White Fulani' breed of cattle has been on the rise inNigeria. The problem most farmers faces with the Friesian hasalways been the adaptation to the weather and endemic diseaseconditions in Nigeria. Fungal infections represent an importantcomplication for immunosuppressed animals and are associatedwith high morbidity and mortality (De Pauw and Meunier, 1999).Fusarium is one of the most important fungal genera, whichincludes many species that are pathogenic to plants and responsible for a broad range of diseases while others are highly mycotoxigenic (Viquez et al., ) and some cause opportunistic infections in humans and in farm animals. Fusarium graminearum (Gibberella zeae) is an importantpathogen of commercial crops such as wheat, maize, and rice.Infection with F. graminearum causes yield losses in grains anddegrades their nutritive, physical and chemical qualities, resultingin their being used for animal feed rather than for human consumption (Charmley et al., 1994). A contaminated crop can be salvaged by feeding it to livestock or poultry, but further losses may be incurred due to the negative effects of mycotoxins on animal performance. Potent toxins such as the estrogenic toxin zearalenone (F-2) have been reported by Vesonder and Hesseltine, (1980) but the most common mycotoxins produced byF. graminearum are deoxynivalenol (DON, also known as vomitoxin), 15-acetyldeoxynivalenol, and nivalenol belonging to a group of compounds known as trichothecenes (Homdork et al., 2000; Council for Agricultural Science and Technology, CAST, 2003). These mycotoxins are known to diminish feed consumption in domestic livestock, especially swine (CAST 2003). Because of their apparent tolerance for higher levels of dietary DON, Fusarium-infested grains are often fed to cattle or sheep asopportunity feeds. This may be due to little or insufficient information describing the pathogenesis and the ability of this plant pathogen to survive as they move through the gastrointestinal tract of cattle or on a compromised skin (Kedar and Gemerlyn, 2008)

Global migration of influenza A viruses in swine

The complex and unresolved evolutionary origins of the 2009 H1N1 influenza pandemic exposed major gaps in our knowledge of the global spatial ecology and evolution of influenza A viruses in swine (swIAVs). Here we undertake an expansive phylogenetic analysis of swIAV sequence data and demonstrate that the global live swine trade strongly predicts the spatial dissemination of swIAVs, with Europe and North America acting as sources of viruses in Asian countries. In contrast, China has the world's largest swine population but is not a major exporter of live swine, and is not an important source of swIAVs in neighbouring Asian countries or globally. A meta-population simulation model incorporating trade data predicts that the global ecology of swIAVs is more complex than previously thought, and the United States and China's large swine populations are unlikely to be representative of swIAV diversity in their respective geographic regions, requiring independent surveillance efforts throughout Latin America and Asia.status: publishe

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency–Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research

Clinical Tetanus in Pigs in a Pig Farming Complex, Lagos, Nigeria

Tetanus is a state of muscular contractions caused by infection of wounds with the bacterium, Clostridium tetani. This bacterium produces toxins that affect the nervous system of both humans and animals. Although tetanus is rare in swine, in this report, we examine two clinical cases of tetanus in a pig farming complex in Lagos, Nigeria. The diagnosis of tetanus in pigs was based on the combination of observed clinical signs, history of castration under non-sterile conditions and presence of animal dung in the environment. To prevent future occurrences of tetanus in pigs, we recommend that there should be improved biosecurity measures on pig farms and farmers should employ the services of veterinarians for health-related issues affecting their pigs, especially in handling cases that require surgical intervention.Keywords: Tetanus, pigs, castration, Nigeri