Abstract
Aim: To investigate molecular and evolutionary characteristics of genes of fowlpox virus (FWPV) isolates from chickens in Tanzania. Study Design: Experimental. Place and Duration of Study: Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; between November 2011 and October 2013. Methodology: Samples of cutaneous nodular lesions were collected from featherless parts of chickens (n = 154) suspected to have fowl pox in 14 regions of Tanzania followed by virus isolation, DNA extraction, polymerase chain reaction (PCR) amplification of the P4b gene, gel electrophoresis of PCR products, purification of PCR products, sequencing Original Research Article British Microbiology Research Journal, 4(7): 759-771, 2014 760 of purified PCR products and finally analysis of sequence data using standard procedures. Results: The disease was confirmed in 12 regions, out of 154 investigated samples 66 (42.86%) were found to contain FWPV, indicating that the 66 chickens from which the samples were collected had fowl pox as a result FWPV infection. Sequence analysis revealed that the Tanzanian FWPV isolates were 99.65 – 100% identical to each other and 99 – 100% identical to several published sequences of FWPV isolates from various countries in different continents of the world, including Europe and Asia. Phylogenetic analysis revealed that all Tanzanian isolates belong to clade A, subclade A1. Conclusion: Based on the findings of this study it is concluded that currently fowl pox is prevalent in several regions of Tanzania, caused by FWPVs which are genetically and phylogenetically closely related. However, these findings do not rule out the possibility of existence of genetic divergence among FWPVs currently prevalent in Tanzania. In order to rule out or detect genetic divergence (if any) among FWPVs currently prevalent in the country, other studies aimed at investigating molecular and evolutionary characteristics of genes in other genomic regions are highly recommended.
Highlights
Fowlpox virus (FWPV) is a DNA virus that belongs to the family Poxviridae, subfamily Chordopoxvirinae and genus Avipoxvirus [1]
3.1.1 Virus isolation Gross pathological changes on chorioallantoic membrane (CAM) were first observed at the third passage, when two to three nodular lesions about 1 mm in diameter were observed on some CAMs without thickening of the CAMs
The lesions were demonstrated in CAMs inoculated with inoculums prepared from 66 samples of cutaneous nodular lesions from chickens in 12 regions (Table 5) and in all CAMs inoculated with inoculums prepared from samples of imported commercial fowl pox vaccines
Summary
Fowlpox virus (FWPV) is a DNA virus that belongs to the family Poxviridae, subfamily Chordopoxvirinae and genus Avipoxvirus [1]. The virus causes fowl pox in chickens. The disease presents itself in three forms; the cutaneous, diphtheritic and systemic form [2,3]. The cutaneous form is characterized by formation of proliferative lesions ranging from papules to nodules in the unfeathered parts of the body, which eventually hardens to form scabs. The diphtheritic form is characterized by formation of fibrous necrotic proliferative lesions in the mucous membrane of the digestive and upper respiratory tracts [4, 5]. In the systemic form various body systems and tissues of an infected bird are involved [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
