Polymorphism of prion protein gene (PRNP) in Nigerian sheep.

Polymorphism of the prion protein gene (PRNP) gene determines an animal's susceptibility to scrapie. Three polymorphisms at codons 136, 154, and 171 have been linked to classical scrapie susceptibility, although many variants of PRNP have been reported. However, no study has investigated scrapie susceptibility in Nigerian sheep from the drier agro-climate zones. In this study, we aimed to identify PRNP polymorphism in nucleotide sequences of 126 Nigerian sheep by comparing them with public available studies on scrapie-affected sheep. Further, we deployed Polyphen-2, PROVEAN, and AMYCO analyses to determine the structure changes produced by the non-synonymous SNPs. Nineteen (19) SNPs were found in Nigerian sheep with 14 being non-synonymous. Interestingly, one novel SNP (T718C) was identified. There was a significant difference (P < 0.05) in the allele frequencies of PRNP codon 154 between sheep in Italy and Nigeria. Based on the prediction by Polyphen-2, R154H was probably damaging while H171Q was benign. Contrarily, all SNPs were neutral via PROVEAN analysis while two haplotypes (HYKK and HDKK) had similar amyloid propensity of PRNP with resistance haplotype in Nigerian sheep. Our study provides valuable information that could be possibly adopted in programs targeted at breeding for scrapie resistance in sheep from tropical regions.

Scrapie-associated polymorphisms of the prion protein gene (PRNP) in Nigerian native goats.

Scrapie is a fatal prion protein disease stiffly associated with single nucleotide polymorphism (SNPs) of the prion protein gene (PRNP). The prevalence of this deadly disease has been reported in small ruminants, including goats. The Nigerian goats are hardy, trypano-tolerant, and contribute to the protein intake of the increasing population. Although scrapie has been reported in Nigerian goats, there is no study on the polymorphism of the PRNP gene. Herein, we evaluated the genetic and allele distributions of PRNP polymorphism in 132 Nigerian goats and compared them with publicly available studies on scrapie-affected goats. We utilized Polyphen-2, PROVEAN and AMYCO programs to examine structural variations produced by the non-synonymous SNPs. Our study revealed 29 SNPs in Nigerian goats, of which 14 were non-synonymous, and 23 were novel. There were significant differences (P < 0.001) in the allele frequencies of PRNP codons 139, 146, 154 and 193 in Nigerian goats compared with scrapie-affected goats, except for Northern Italian goats at codon 154. Based on the prediction by Polyphen-2, R139S and N146S were 'benign', R154H was 'probably damaging', and T193I was 'possibly damaging'. In contrast, PROVEAN predicted 'neutral' for all non-synonymous SNPs, while AMYCO showed a similar amyloid propensity of PRNP for resistant haplotype and two haplotypes of Nigerian goats. Our study is the first to investigate the polymorphism of scrapie-related genes in Nigerian goats.

Analysis of Amino Acid Changes in the Fusion Protein of Virulent Newcastle Disease Virus from Vaccinated Poultry in Nigerian Isolates.

The roles of fusion gene in the virulence of Newcastle disease virus are well established, but the extent of its variation among the XIV, XVII, and XVIII genotypes reported in Central Africa and West Africa has until recently been understudied. In this study, virulent Newcastle disease virus (vNDV) was isolated from dead chickens among vaccinated flocks between March and April 2020. Fusion (F) gene was sequenced and analysed for characterization and information about genetic changes. Many substitutions were observed along the region and some of their functions are yet to be determined. Results showed that all study isolates have virulent cleavage site sequence 112-RRRKR-116/F117 and clustered within genotype XIVb. Sequence analysis showed K78R mutation in the A2 antigenic epitope in all isolates and more along the F-gene which varied in some instances within the isolates. Mutation in this A2 antigenic epitope has been reported to induce escape mutation to monoclonal antibodies generated using the NDV LaSota strain. The range of percentage nucleotide and amino acid homology between the study isolates and commercially available vaccine strains is 81.14%-84.39% and 0.175-0.211, respectively. This report provides evidence of vNDV among vaccinated chicken flock and molecular information about circulating vNDV strains in Kano State, Nigeria, which is useful for the development of virus matched vaccines. Newcastle disease (ND) surveillance and molecular analysis of circulating strains in this region should be encouraged and reported. Furthermore, ND outbreaks or cases among vaccinated poultry presented to veterinary clinics should be reported to the state epidemiologist. Nucleotide sequences were assigned accession numbers OK491971-OK491977.

Salmonella Serovars, Antibiotic Resistance, and Virulence Factors Isolated from Intestinal Content of Slaughtered Chickens and Ready-to-Eat Chicken Gizzards in the Ilorin Metropolis, Kwara State, Nigeria.

Salmonellosis is one of the most common and widely distributed food-borne diseases, and the presence of antimicrobial-resistant Salmonella in poultry and poultry products is a global public health problem. Therefore, a cross-sectional study was conducted from November 2016 to July 2017 with an aim of determining the isolation rates of Salmonella species from the intestinal contents of slaughtered chickens, the most common serotypes that invade and colonize the tissues of chickens in Ilorin, and the susceptibilities of the isolated species to commonly used antibiotics. Four hundred samples of intestinal contents from apparently healthy slaughtered chickens and one hundred ready-to-eat chicken gizzards in Ilorin, Kwara State, were examined for the presence of Salmonella and their serotypes. Salmonellae were isolated and identified according to the techniques recommended by the World Health Organization: preenrichment, selective plating, biochemical testing, and serotyping. A total number of forty-three (43) Salmonella isolates consisting of 33 from intestinal contents and 10 from ready-to-eat chicken gizzards were isolated and identified. There was an overall Salmonella prevalence rate of 8.6% (43/500), and the isolates were distributed as follows: gizzard, 2% (n = 10) and intestinal contents, 6.6% (n = 33). The predominant serovars were Salmonella enterica subsp. enterica serovar 45: d: 1, 7 (16) and S. Haifa (5). All ready-to-eat chicken gizzards were associated with Salmonella enterica subsp. enterica serovar 45: d: 1, 7 (5). The Salmonella from intestinal contents belong to Salmonella enterica subsp. enterica serovars 45: d: 1, 7 (11) and S. Haifa (5). Salmonella species isolated were 100% resistant to ciprofloxacin, ampicillin, and ceftazidime. This is followed by cloxacillin (81%), tetracycline (75%), and sulfamethoxazole (67%). The Salmonella isolates were, however, 100% sensitive to enrofloxacin, 74% to streptomycin, and 72% to gentamycin antibiotics. The most common serotype was S. enterica subsp. enterica serovar 45: d: 1, 7. All the twenty five Salmonella serovars consisting of twenty-one serotypes (n = 21), two of the Salmonella that could not be cultured after enrichment, and the two that were contaminated with Proteus possessed the virulence genes of invA and stn. The Salmonella enterica subsp. enterica serovar 45: d: 1, 7 and S. Haifa possess virulence genes so they are potentially virulent for humans in this area. The national and local health authorities in Nigeria should improve hygiene measures especially at retail slaughter markets to reduce salmonellosis which is one of the most important food-borne diseases in humans.

Diagnosis, management and prognosis of obstructive jaundice in Ile-Ife, Nigeria.

A 5-year review of 50 patients, 28 males, 22 females, with a mean age of 42 years, operated for obstructive jaundice at Ile-Ife, Nigeria was undertaken. Neoplasms of the pancreas, liver, and bile duct were the common causes. Percutaneous Transhepatic Cholangiography (PTC) with hypotonic duodenography was excellent in determining the underlying lesions. Pancreatic carcinoma accounted for 28% of cases, cholelithiasis 24%, hepatoma 22%, metastatic cancer 14%, bile duct carcinoma 10%, and traumatic pancreatic pseudocyst 2%. The patients with malignancies were older than those with biliary calculi. Biochemically, elevated alkaline phosphatase, and conjugated hyperbilirubinaemia, particularly in malignant obstructions, were diagnostic. Benigh bile ductal obstructions were surgically managed without any mortality. Malignant obstructions were surgically managed without any mortality. Malignant obstructions with their advanced presentations were less successfully managed. Biopsy alone or palliative bypass procedure could only be offered and the survival rate was dismal.

Gastric volvulus in Nigerian patients: report of four cases.

Gastric volvulus is an uncommon foregut condition. Literature survey based on Medline search between 1993 and end of 1996 indicated there were thus far approximately 750 cases of gastric volvulus with 100 involving children. Gastric volvulus frequently presents in chronic or recurrent form and symptoms are usually non-specific causing delay in diagnosis. The acute type is however potentially lethal if not properly managed. Four cases, an acute volvulus in a child and three chronic lesions in adults are presented with a discussion of the pathology, aetiology, manifestations and treatment of the condition.