Avian leukosis virus subgroup - J as a contaminant in live commercially available poultry vaccines distributed in Nigeria.

Globally, vaccines are used to prevent and control the menace of infectious diseases in livestock with some reported to be inadvertently contaminated with extraneous agents (EAs). With the aim of screening and characterizing for some selected EAs, 44 live viral poultry vaccines were randomly selected based on availability. The vaccines comprised 14 manufacturers in 10 different countries including Nigeria were screened by Polymerase Chain Reaction. In 9% (4/44) of the vaccines, contamination with only avian leukosis virus (ALV) subgroup J (ALV-J) was recorded. Other exogenous ALV subgroups, chicken infectious anemia and infectious laryngotracheitis viruses were absent. The EAs was found in infectious bursal disease (n = 1), Fowlpox (n = 2) and Mareks disease (n = 1) vaccines. Phylogenetic analysis of the ALV-J env gene showed clustering with contemporary group I and II. The result underscores the importance of screening vaccines to avoid the introduction and spread of EAs that could pose a threat to poultry production.

First report of co-infections of Marek's disease virus and chicken infectious anaemia virus in poultry flocks in Nigeria.

Marek's disease (MD) and chicken infectious anaemia (CIA) are viral immunosuppressive diseases of poultry caused by the MD virus (MDV) and CIA virus (CIAV) respectively. Despite vaccination against MD, the incidence of the disease in vaccinated poultry flocks in Nigeria persists. However, underlying factors like co-infection with CIAV have not been investigated in the country. This study was designed to investigate possible co-infections of MDV and CIAV in poultry flocks in Nigeria. In 2016, tumorous tissue samples were collected from suspected cases of MD at necropsy in Jos, Plateau State, Nigeria. The samples collected were fixed in formalin for histopathological examination, genomic DNA was extracted from a second part and analysed by polymerase chain reaction (PCR), targeting the meq and VP1 genes of the MDV and CIAV, respectively. The histology results revealed that the cutaneous and proventricular lymphomas were characterized by large numbers of mononuclear cellular infiltrates admixed with heterophils. The PCR results revealed that MDV was detected in 66.7% (16/24), CIAV in 45.8% (11/24), and co-infections of MDV and CIAV were detected in 45.8% (11/24) of the samples analysed. In addition, co-infections of MD and CIA were recorded in 100% (6/6) and 27.7% (5/18) of broilers and layer/pullet' samples respectively. Phylogenetic analysis of the meq gene sequences revealed that the Nigerian MDV clusters with very virulent MDV from Egypt and Italy. While, CIAV sequences were genotype II and genotype III and clustered with CIAVs from Cameroon and China. This is the first report of co-infections of MD and CIA in Nigeria.

Applied One Health: Nigeria National Veterinary Research Institute COVID-19 pandemic response.

The COVID-19 pandemic has caused the death of 7.1 million people worldwide as of 7 July 2024. In Nigeria, the first confirmed case was reported on 27 February 2020, subsequently followed by a nationwide spread of SARS-CoV-2 with morbidity and mortality reaching 267 173 and 3155, respectively, as of 7 July 2024. At the beginning of the pandemic, only a few public health laboratories in Nigeria had the capacity for SARS-CoV-2 molecular diagnosis. The National Veterinary Research Institute (NVRI), already experienced in influenza diagnosis, responded to the public health challenge for the diagnosis of COVID-19 samples from humans. The feat was possible through the collective utilisation of NVRI human and material resources, including biosafety facilities, equipment, reagents and consumables donated by international partners and collaborators. Within 6 months of the reported COVID-19 outbreak in Nigeria, over 33 000 samples were processed in NVRI facilities covering five states. Thereafter, many field and laboratory projects were jointly implemented between NVRI and collaborating sectors including the Nigerian Centre for Disease Control (NCDC) and the National Institute for Medical Research (NIMR), which brought together professionals in the health, veterinary, education and socio-sciences. In addition, One Health grants were secured to enhance surveillance for coronavirus and other zoonoses and build capacity in genomics. Bio-surveillance for coronaviruses and other emerging zoonotic pathogens at the human-animal interface was activated and continued with sample collection and analysis in the laboratory for coronaviruses, Lassa fever virus and Mpox. One Health approach has shown that inter-sectoral and multinational collaboration for diagnosis, research and development in animals, and the environment to better understand pathogen spillover events at the human-animal interface is an important global health priority and pandemic preparedness.

Effect of ascorbic acid administration on erythrocyte osmotic fragility of pigs transported by road during the hot-dry season.

The experiments were performed in order to determine the effect of 8-h road transportation of pigs on erythrocytes osmotic fragility during the hot-dry season, and the ameliorative role of ascorbic acid. Twenty-three adult pigs comprising of both sexes served as subjects for the study. Thirteen pigs administered ascorbic acid (AA) per os 30 min before transportation, at a dose rate of 100 mg/kg served as experimental animals, while ten pigs administered with distilled water per os served as control, and were transported for 8 h during the hot-dry season. EDTA blood samples collected a day before (pre-transportation), immediately after 8-h transportation and 7 days post-transportation were used to determine erythrocyte osmotic fragility. The ambient temperature (AT) and relative humidity (RH) measured within the vehicle ranged between 30.5-39.0 °C and 40.0-71.0% respectively. These values were outside the thermoneutral zone for the pig, indicating that the season was thermally stressful. Results obtained showed a significant difference (p<0.05) in percent haemolysis recorded at NaCl concentrations of 0.4% and 0.6% immediately after transportation in experimental pigs and at 0.5, 0.6, 0.8 and 0.9% NaCl concentrations in experimental pigs 7 days post-transportation. In conclusion, result from the present study indicated that 8-h road transportation during the hot-dry season could induce stress resulting in haemolysis of erythrocytes and AA administration ameliorated the stress.