Oxyspirura petrowi infection leads to pathological consequences in Northern bobwhite ( Colinus virginianus )

Abstract

Debilitating ocular diseases are often reported in avian species. By and large, helminth parasites have been overlooked in avian diseases and regarded as inconsequential. The decline of Northern bobwhite quail (Colinus virginianus) in the Rolling Plains ecoregion of Texas has prompted an investigation of the factors influencing their disappearance. Infection by the eyeworm (Oxyspirura petrowi) has been documented in many avian species; however, the effect it has on its host is not well understood. Heavy eyeworm infection has been documented in Northern bobwhites throughout this ecoregion, leading to eye pathology in this host species. The present study further documents and supports the pathological changes associated with O. petrowi in bobwhites.

Predicting seasonal infection of eyeworm (Oxyspirura petrowi) and caecal worm (Aulonocephalus pennula) in northern bobwhite quail (Colinus virginianus) of the Rolling Plains Ecoregion of Texas, USA

“…Euthanasia and necropsies were performed as described in Dunham et al (2014). Eyeworms were extracted from the eyes by removing the eyeball and associated tissues into a petri dish as outlined in Dunham et al (2016a). Caecal worm collection followed protocols described in Dunham et al (2017b) where caeca were removed and placed in a 20-mesh sieve, then cut into smaller sections to assess caecal worm count.…”

“…The heteroxenous eyeworm is typically found under the nictitating membrane, lacrimal ducts and glands, and the orbital cavity of the bobwhite (Saunders, 1935; Addison and Anderson, 1969; Robel et al, 2003; Dunham et al, 2014; Bruno et al, 2015; Dunham and Kendall, 2017). Pathological investigations by Dunham et al (2016a) and Bruno et al (2015) found inflammation in the lacrimal duct and lesions on the Harderian gland. This is of great concern when considering these two tissues’ importance to saturation of the eye (Holly and Lemp, 1977) and immune response (Payne, 1994), respectively.…”

“Weight of evidence” as a tool for evaluating disease in wildlife: An example assessing parasitic infection in Northern bobwhite (Colinus virginianus)

“…Anecdotal accounts of eyeworm infected bobwhite from the Rolling Plains exhibiting erratic behavior ( Jackson, 1969 ) spurred concerns that these parasites may be causing visual impairment by damaging structures within the eyes of infected individuals. Later, researchers conducted pathological assessments of the eyes of infected bobwhite and confirmed inflammation and damage to the eye tissues and cornea of bobwhite hosts, as well as hemorrhaging of nasolacrimal ducts ( Bruno et al, 2015 ; Dunham et al, 2015 , 2016b ; Hunter, 2016 ). Because bobwhite are highly dependent on their sense of vision when foraging, navigating their environment, and evading predators, the potential effects of impaired vision may be substantial.…”

Mycobacterieel conjunctivaal granuloom bij een Chinese zaagbekeend (Mergus squamatus)

“…en Cryptosporidium spp. en myiasis (Abrams et al, 2002;Dubey, 2002;Elias et al, 2008;Lopez et al, 2010;Church et al, 2013;Dunham et al, 2016). Veel van deze parasieten komen echter zelden voor in West-Europa en infecties worden vaak uitsluitend waargenomen bij in het wild levende dieren of in het wild gevangen dieren.…”