Occurrence of infectious bronchitis in layer birds in Plateau state, north central Nigeria.
Open Vet J
; 9(1): 74-80, 2019 04.
Article
in En
| MEDLINE
| ID: mdl-31086770
ABSTRACT
A flock of 54 wk-old layer birds exhibiting signs of respiratory distress, greenish diarrhea, and drop in egg production was investigated. A marked drop in egg production (55%) was recorded with eggs appearing white and soft-shelled. Mortality was in the range of 1%-2% with post-mortem lesions revealing cloudy air sacs, frothy, and congested lungs. Viral RNA was extracted from pooled tissue samples (trachea, lungs, spleen, and liver) and tested for Avian influenza virus (AIV), Newcastle disease virus (NDV), and infectious bronchitis virus (IBV) by reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, virus isolation was attempted in 9-11 day-old embryonating chicken eggs (ECE). In order to determine the prevalence of IBV serotype(s) in the flock, serum samples were screened by hemagglutination-inhibition (HI) test using IBV antigens and antisera (Arkansas, Connecticut, and Massachusetts). Neither AIV nor NDV but IBV was detected in the tissue samples by RT-PCR. In addition, virus isolate obtained after four serial passages in ECE produced dwarfed, stunted, and hemorrhagic embryos, and the isolate was confirmed by RT-PCR to be IBV. The serum samples were 100% seropositive for three serotypes with HI titres ranging from 5 to 12 Log2. In this study, IBV was confirmed as the causative agent of the observed respiratory distress and drop in egg production. Also, the evidence of co-circulation of multiple IBV serotypes was established, this to the best of our knowledge is the first of such report in Nigeria. We recommend extensive molecular and sero-epidemiology of circulating IBV genotypes and serotypes in Nigeria with the aim of developing better control strategies, including vaccination.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Poultry Diseases
/
Bronchitis
/
Chickens
/
Coronavirus Infections
/
Infectious bronchitis virus
Type of study:
Prevalence_studies
/
Risk_factors_studies
Limits:
Animals
Country/Region as subject:
Africa
Language:
En
Journal:
Open Vet J
Year:
2019
Document type:
Article
Affiliation country:
Nigeria