BackgroundOxyspirura petrowi appears to be emerging as a nematode parasite that could negatively impact Northern Bobwhite quail individuals and populations within Texas and other regions of the United States. Despite this eye worm's potential importance in the conservation of wild quail, little is known about the general biology and genome composition of O. petrowi. To fill the knowledge gap, we performed a small scale random genome sequence survey, sequenced its 18S rRNA and the intergenic region between the 18S and 28S rRNA genes, studied its phylogenetic affinity, and developed a PCR protocol for the detection of this eye worm.ResultsWe have generated ~240 kb of genome sequence data derived from 348 clones by a random genome survey of an O. petrowi genomic library. The eye worm genome is AT-rich (i.e., 62.2% AT-content), and contains a high number of microsatellite sequences. The discovered genes encode a wide-range of proteins including hypothetical proteins, enzymes, nematode-specific proteins. Phylogenetic analysis based on 18S rRNA sequences indicate that the Spiruroidea is paraphyletic, in which Oxyspirura and its closely related species are sisters to the filarial nematodes. We have also developed a PCR protocol based on the ITS2 sequence that allows sensitive and specific detection of eye worm DNA in feces. Using this newly developed protocol, we have determined that ~28% to 33% of the fecal samples collected from Northern Bobwhites and Scaled Quail in Texas in the spring of 2013 are O. petrowi positive.ConclusionsThe O. petrowi genome is rich in microsatellite sequences that may be used in future genotyping and molecular fingerprinting analysis. This eye worm is evolutionarily close to the filarial nematodes, implying that therapeutic strategies for filariasis such as Loa loa would be referential in developing treatments for the Thelazoidea parasites. Our qPCR-based survey has confirmed that O. petrowi infection is of potential concern to quail managers in Texas.

The objective of this study was to determine the prevalence of avian influenza viruses (AIV) in bobwhite quail (Colinus virginianus) populations from the rolling plains of Texas, U. S. A. A total of 1320 swab samples (652 tracheal swabs and 668 cloacal swabs) and 44 serum samples were collected from wild-captured or hunter-harvested bobwhite quail from November 2009 to April 2011 at the Rolling Planes Quail Research Ranch, Fisher County, Texas, U. S. A. The presence of AIV in the swabs was determined by real-time reverse-transcription-PCR (rRT-PCR) and all samples positive or suspicious by rRT-PCR were further processed for virus isolation in embryonated chicken eggs. A total of 18 (1.4%) swab samples tested positive for AIV by rRT-PCR (cycle threshold [Ct] values < 35): 13 cloacal swabs (1.9%) and 5 tracheal swabs (0.8%). In addition, 100 (7.6%) swab samples were considered suspicious (Ct values 35.1-40): 69 cloacal swabs (10.3%) and 31 tracheal swabs (4.7%). No virus was isolated from any of the rRT-PCR-positive or suspicious samples tested. Additionally, 44 serum samples were screened for AIV antibodies and were negative. The results presented here indicate low prevalence of AIV in wild populations of bobwhite quail.

We developed nested PCR protocols and performed a multiyear survey on the prevalence of several protozoan parasites in wild northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) in the Rolling Plains ecoregion of Texas and Oklahoma (i.e. fecal pellets, bird intestines and blood smears collected between 2010 and 2013). Coccidia, cryptosporidia, and microsporidia were detected in 46.2%, 11.7%, and 44.0% of the samples (n = 687), whereas histomona and hematozoa were undetected. Coccidia consisted of one major and two minor Eimeria species. Cryptosporidia were represented by a major unknown Cryptosporidium species and Cryptosporidium baileyi. Detected microsporidia species were highly diverse, in which only 11% were native avian parasites including Encephalitozoon hellem and Encephalitozoon cuniculi, whereas 33% were closely related to species from insects (e.g. Antonospora, Liebermannia, and Sporanauta). This survey suggests that coccidia infections are a significant risk factor in the health of wild quail while cryptosporidia and microsporidia may be much less significant than coccidiosis. In addition, the presence of E. hellem and E. cuniculi (known to cause opportunistic infections in humans) suggests that wild quail could serve as a reservoir for human microsporidian pathogens, and individuals with compromised or weakened immunity should probably take precautions while directly handling wild quail.

Trapping of northern bobwhites (Colinus virginianus) is commonly conducted for research purposes. We investigated the influence of weather, lunar phase, time of day, and season on bobwhite trapping success in the Rolling Plains ecoregion of Texas, USA, from 2009 to 2011. We trapped bobwhites in autumn (Oct–Nov) and spring (Feb–Mar) using walk‐in funnel traps baited with sorghum. We used a negative binomial regression to examine effects of temperature, humidity, wind speed, lunar phase, time of day, season, the number of traps set, and year on the number of bobwhites captured per trapping session. More bobwhites were trapped during the spring, in the evenings, and when temperatures were cooler. There was also some evidence for an influence of lunar phase on the number of bobwhites captured with greater counts during the new moon and third quarter. These variables may be important to consider for maximizing catch‐per‐unit‐effort, when using trapping data to estimate relative abundance, or when conducting mark–recapture studies. © 2016 The Wildlife Society.

Northern bobwhite (Colinus virginianus) populations are monitored using 2 general approaches—population indices and abundance estimators. Due to their convenient sampling designs, indices are commonly used by land managers and researchers to predict or estimate hunting‐season populations. We evaluated the efficacy of 4 bobwhite indices (spring cock [adult male] call‐counts, autumn covey call‐counts, roadside surveys, and helicopter surveys) to predict hunting‐season population size by relating them to abundance estimators (minimum known population [no. unique trapped individuals each year], mark–recapture, helicopter‐based distance sampling). Data were collected at the Rolling Plains Quail Research Ranch in Fisher County, Texas, USA, during 2009–2018. Spring cock call‐counts and autumn covey call‐counts were analyzed at 2 spatial scales: ranch scale (1,781 ha) and point scale (i.e., within the presumed radius of audibility of listening points; 600 m or 113 ha). Roadside and helicopter surveys were conducted at the ranch scale along 31‐ and 90‐km transects, respectively. At the ranch scale, mean spring cock call‐counts were a modest predictor of minimum known populations (r2 = 0.54) and good predictor of mark–recapture estimates (r2 = 0.80). At the point scale, the mean number of cocks heard was a poor predictor of densities surrounding points (r2 = 0.0003) as estimated by distance sampling. The mean number of coveys heard during autumn counts was a significant predictor of both minimum known populations (r2 = 0.88) and mark–recapture estimates (r2 = 0.85) at the ranch scale but was a weak predictor of densities immediately surrounding listening points (r2 = 0.22). Helicopter surveys during November (individuals/km) were a significant predictor of minimum known populations (r2 = 0.98) and mark–recapture (r2 = 0.93). Overall, roadside surveys (individuals/km) conducted during September was the best index for predicting minimum known populations (r2 = 0.99) and mark–recapture estimates (r2 = 0.97). Our results suggest the linear relationship between indices and autumn–winter populations for bobwhite are stronger when conducted closer in time to hunting season and at larger scales. © 2019 The Wildlife Society.