Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 13, 2009
Publication Date: March 25, 2010
Citation: Marusak, R.A., Guy, J.S., Abdul-Aziz, T.A., West, M.A., Fletcher, 0.J., Day, J.M., Zsak, L., Barnes, H.J. 2010. Parvovirus associated cerebellar hypoplasia in day-old chickens. Avian Diseases. 54:156-160. Interpretive Summary: Neurologic disease is a common cause of early culling and death in both chickens and turkeys. Two neurologic diseases characterized by abnormal brain anatomy are cerebellar hypoplasia (CH) and cerebellar abiotrophy (CA). Although these conditions are common in mammals, reports in birds are rare. Parvovirus is known to cause cerebellar hypoplasia in both kittens and puppies, although in the dog, the enteric form of parvovirus infection is most prevalent. Parvovirus is also a well-characterized enteric pathogen of young geese and muscovy ducks and has been described in both turkeys and chickens; parvovirus has been associated with poult enteritis complex in turkeys and runting-stunting syndrome in chickens. This paper describes the first case of CH and hydrocephalus in commercial broiler chickens showing both enteric disease and neurologic signs. Evidence for the association of chicken parvovirus in this disease was provided by detection of parvovirus deoxyribonucleic acid (DNA) in affected brains using a molecular diagnostic test.
Technical Abstract: Cerebellar hypoplasia and hydrocephalus were detected in day-old broiler chickens. Brains of chickens evaluated at necropsy appeared to be abnormal; some were disfigured and cerebellae appeared to be smaller than normal. Histopathologic examination of brains revealed cerebellar folia that were shortened and misshapen. Focal loss of the internal granular cell layer was observed along the base of some of the folia; in these areas, Purkinje cells were disorganized and present within the molecular layer. Parvovirus deoxyribonucleic acid (DNA) was detected in 3/9 brains examined by polymerase chain reaction using oligonucleotide primers designed for amplification of chicken and turkey parvoviruses. Based on phylogenetic analyses, the detected virus most closely resembled chicken parvoviruses. These findings identify a chicken parvovirus as a possible cause of neurologic disease in young chickens; however, its role in this disease remains to be established.