Molecular Diagnosis and Pathology of Chicken
Infectious Anemia in Commercial White Leghorn Layer Flocks in
Pakistan
Najm-ul-Islam1, Muhammad Kashif
Saleemi2*, Muhammad Zargham Khan2, Salman
Latif Butt2, Ahrar Khan2, Ijaz Javed3,
Faisal Saeed Awan4and ShahidRafique5
1Department
of Livestock and Dairy Development (Poultry Production), Faisalabad;
2Department of Pathology; 3Department of
Physiology and Pharmacology; 4Centre of Agricultural
Biochemistry and Biotechnology (CABB), University of Agriculture,
Faisalabad, Pakistan; 5Animal Sciences Division, Pakistan
Agricultural Research Council, Islamabad, Pakistan *Corresponding author:drkashif313@yahoo.com
Abstract
The present field study was conducted for
confirmation of chicken infectious anemia (CIA) in White Leghorn (WL) commercial
layer birds. A total of 60 farms were investigated. Birds from each farm ware
necropsied for the presence of lesions on different visceral organs. Samples of
blood and different tissues were collected for hematology, histopathology, DNA
extraction and PCR amplification using specific primers for CIA virus. There was
severe anemia indicated by low hematocrit values (10.9 to 17.2%) and hemoglobin
concentration (5.3 to6.7 g/dl). The petechial hemorrhages were present on
subcutaneous tissue, epicardium, endocardium and gizzard mucosa. The liver and
bone marrow were pale in appearance. The mortality ranged from 5 to14 % on
different farms. Samples of liver and spleen from 15 farms were subjected to PCR
analysis for CIAV infection by amplifying the186-bp region on highly conserved
VP-2 coding gene using CAV1 and CAV2 primer pair.Presence of CIAV was confirmed in 67 and 33 percent samples of liver and
spleen, respectively. A total of 13/15 farms (87%) were found positive for CIA.The results of present study confirmed the presence of CAV infection in
WL commercial layer birds in current outbreak.It is concluded that extensive molecular epidemiological studies are
required at national level to assess the prevalence of disease. Breeder flocks
should be vaccinated to control CIA in commercial layer flocks.
Key words: Bone marrow, Liver, Polymerase chain reaction,
Spleen, White Leghorn