EYEWORMS (OXYSPIRURA PETROWI) IN NORTHERN BOBWHITES (COLINUS VIRGINIANUS) FROM THE ROLLING PLAINS ECOREGION OF TEXAS AND OKLAHOMA, 2011−13

Abstract

The Northern Bobwhite ( Colinus virginianus ) has been steadily declining throughout much of its historic range for decades. The Rolling Plains ecoregion of Texas and western Oklahoma, historically rich with wild Northern Bobwhites and one of the last remaining quail strongholds, also has a declining population. During August and October in 2011-13, 348 Northern Bobwhites from the Rolling Plains were examined for eyeworms (Oxyspirura petrowi). Of these 348 Northern Bobwhites, 144 (41.4%) were infected with 1,018 total eyeworms. Eyeworm abundance (mean±SE) was 2.9±0.4 (range 0-64), with an intensity (mean±SE) of 7.1±0.6. Eyeworm prevalence was significantly higher in adult Northern Bobwhites (58.7%) than in juveniles (35.4%). Recent research suggests that eyeworms have the potential to cause cellular tissue damage to the eye, but it is unknown how these worms affect host survivability. This study further expands the regional distribution of O. petrowi in Northern Bobwhites in the Rolling Plains ecoregion and assesses the prevalence and abundance of infection across host age, host sex, and year. Further research is warranted on the life history of O. petrowi and assessing the impacts of eyeworms on their definitive host at individual and population levels.

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

“…Recently, a parasitic eyeworm ( Oxyspirura petrowi ) has received increased attention due to the high prevalence detected in native galliforme populations in the United States ( Robel et al., 2003 , Villarreal et al., 2012 , Dunham et al., 2016 ). Specifically, the decline of the Northern bobwhite ( Colinus virginianus ) in west Texas has prompted an investigation of the factors influencing the disappearance of these birds.…”

“…Helminth parasites have been overlooked historically ( Lehman, 1984 ), but eyeworm infections are now considered a possible factor contributing to the decline of Northern bobwhites in Texas ( Dunham et al., 2014 , Dunham et al., 2016 , Bruno et al., 2015 ). Oxyspiurura petrowi is a heteroxenous parasitic nematode reported to infect the eyes of many avian hosts ( Dunham and Kendall, 2016 ) with species of this genus being documented in >80 avian species worldwide ( Addison and Anderson, 1969 ).…”

“…There has been interest in studying eyeworm infection in Northern bobwhite ( Colinus virginianus ) since recent research discovered that this parasite is endemic to the Rolling Plains ecoregion of Texas and Oklahoma ( Dunham et al., 2016 ). Over the past few years, eyeworm infection has been documented extensively in bobwhites throughout the ecoregion and led researchers to examine the potential influence that parasites have on their decline ( Villarreal et al., 2012 , Xiang et al., 2013 , Dunham et al., 2014 ).…”

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

“…pennula and O . petrowi to be ubiquitous in quail throughout the region ( Dunham et al, 2016a ; Olsen and Fedynich, 2016 ). In subsequent studies, Bruno et al (2019b) found 40% of bobwhite sampled from 2011 to 2013 to be infected with O .…”

Molecular detection of Oxyspirura larvae in arthropod intermediate hosts

“…During this study, 348 northern bobwhites were screened for different pathogens. Infection rates of 41.4% of bobwhite collected from individual sites in the Rolling Plains ecoregion by the parasitic nematode eyeworm Oxyspirura petrowi (Spirurida:Thelaziidae) was reported (Dunham et al 2016 ).

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