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The Northern Bobwhite (Colinus virginianus) has been undergoing a range-wide population decline. Potential causes for declines across its historic range have been investigated for decades and include habitat loss and fragmentation and a variety of parasitic and infectious diseases. Although there have been studies on bobwhite ecology in Oklahoma, USA, relatively little is known about parasites and pathogens in the region. We evaluated the health of free-ranging bobwhites from nine sites in western Oklahoma. From 2018 to 2020, 206 bobwhites were evaluated for gross and microscopic lesions and tested for selected pathogens. In general, bobwhites were in good nutritional condition with ample muscle mass and fat stores. No significant gross lesions were observed in any bobwhite and no significant histologic lesions were detected in a subset. There was no evidence of infection with or exposure to reticuloendotheliosis virus, West Nile virus, respiratory Mycoplasmataceae species, Pasteurella multocida, intestinal Eimeria spp., or oral Trichomonas spp. Several pathogens of potential concern were detected, including avian adenovirus (8.6%), Toxoplasma gondii (2.3%), and haemosporidians (a Haemoproteus sp. (1.5%), Leucocytozoon schoutedeni (1.5%), and Plasmodium homopolare haplotype 2 [lineage LAIRI01; 3.6%]). Physaloptera sp. (12%) and Sarcocystis sp. (1%) were detected in the breast muscle. Low intraspecific genetic diversity was noted for Physaloptera sp., and sequences were most similar to Physaloptera sequences from bobwhites and grasshoppers (Orthoptera) in Texas. Low intensities of chewing lice, chiggers, and ticks were observed. A subset of bobwhites had evidence of exposure to selected toxicants and heavy metals; a small number had low levels of iron, manganese, zinc, molybdenum, and copper, which were not considered diagnostically relevant. In general, bobwhites from western Oklahoma appeared to be in good health with a low diversity of pathogens detected, but future work is needed to understand potentially changing disease risks for this population., (© Wildlife Disease Association 2024.)

This study was conducted to determine how reducing the parasite burden in a definitive host may affect the prevalence in intermediate hosts. Here we used the eyeworm Oxyspirura petrowi and cecal worm Aulonocephalus pennula as model species. Northern bobwhite quail (Colinus virginianus) were provided an anthelmintic medicated feed in wild systems because of convincing evidence that these parasites were suppressing their populations. Eyeworm and cecal worm prevalence were measured in Orthopterans, which act as intermediate hosts, using polymerase chain reaction. Individuals were collected from a control site, a site treated for 2 yr, and a site treated for 5 yr. Orthopteran community composition was significantly different among the sites; however, an interaction between subfamily and site was not significant for the eyeworm. There was a significant reduction in eyeworm-infected Orthopterans on the 5-yr site compared with the other 2, suggesting that treatment of a definitive host may indeed affect the prevalence of eyeworms during other life-cycle stages. There was an interaction between the Orthopteran subfamily and the site for the cecal worm, so results were analyzed within each subfamily. A significant reduction in the prevalence of cecal worms was only found in the Cyrtacanthacridinae subfamily on the 5-yr site when compared with the other sites. However, the greatest prevalence in the Gomphocerinae and Oedipodinae subfamilies across all 3 sites was 4.1%. This indicates an unknown degree of cecal worm host specificity. Therefore, conclusions could not be made through the simple assessment of prevalence., (© American Society of Parasitologists 2023.)

The northern bobwhite (Colinus virginianus) is a popular upland game bird that is suffering from severe and ongoing population decline. In this study, we investigated the potential health impacts of gastrointestinal and periorbital parasites in bobwhite in western Oklahoma, USA. A sample of 206 bobwhites from 2018 to 2020 indicated a low prevalence and diversity of parasites. However, at least one gastrointestinal or ocular parasite species was detected in 112 bobwhite (54.4%). A total of three gastrointestinal parasite species were detected, including Aulonocephalus pennula (54% prevalence, mean intensity 71.6 ± 99.8), Raillietina spp. (7%, 4.2 ± 1.9), and a single immature Mediorhynchus sp. acanthocephalan (0.5%). Burdens of A. pennula infections were negatively associated with fat stores in their bobwhite host. Low intensities (range 1-10, mean 3.9 ± 2.9) of eyeworms (Oxyspirura petrowi) were observed in 12.6% (26/206) of bobwhite sampled and were not associated with fat stores. No significant histologic lesions were associated with O. petrowi worms in ocular and surrounding tissues of 68 quail eyes examined, of which 26 (38%) were positive for eyeworms. Overall, the prevalence and intensity of parasites in bobwhite in Oklahoma were lower than in previous studies in Texas in similar physiographic regions. However, continued studies on the impacts of these parasites on quail health are needed as environmental and climate changes could alter the ecology and significance of these parasites., Competing Interests: Declaration of Competing Interest We wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome. We confirm that the manuscript has been read and approved by all named authors and that there are no other persons who satisfied the criteria for authorship but are not listed. We further confirm that the order of authors listed in the manuscript has been approved by all of us. We confirm that we have given due consideration to the protection of intellectual property associated with this work and that there are no impediments to publication, including the timing of publication, with respect to intellectual property. In so doing we confirm that we have followed the regulations of our institutions concerning intellectual property. We understand that the Corresponding Author is the sole contact for the Editorial process (including Editorial Manager and direct communications with the office). He/she is responsible for communicating with the other authors about progress, submissions of revisions and final approval of proofs. We confirm that we have provided a current, correct email address which is accessible by the Corresponding Author and which has been configured to accept email from myabsley@uga.edu., (Copyright © 2023. Published by Elsevier B.V.)

Helminths, in particular eyeworms (Oxyspirura petrowi) and cecal worms (Aulonocephalus pennula), may be a factor influencing northern bobwhite (Colinus virginianus) populations in Texas. Previous research has shown a discrepancy in helminth infections between the Rolling Plains and Rio Grande Plains of Texas, US, potentially caused by differences in intermediate host distribution and abundance. We explored an alternative hypothesis centered on plant diversity, given that many plants possess phytochemicals with anthelmintic properties. We predicted that plant diversity would be greater and bobwhite diet more diverse in the Rio Grande Plains than the Rolling Plains, which in turn would potentially expose bobwhites to more plants with anthelmintic properties and therefore result in lower parasite prevalence and intensity. We conducted a literature review of plant diversity, anthelmintic plants, and bobwhite diet in Texas to explore this hypothesis. We also quantified the relationship between helminth prevalence in bobwhites and latitude. We documented trends for higher plant species richness, greater number of anthelmintic plants, and more diverse bobwhite diet in the Rio Grande Plains compared to the Rolling Plains. In addition, we documented a trend for increasing helminth prevalence with latitude for eyeworms but not cecal worms. Our study provides circumstantial evidence supporting the plant-diversity hypothesis and warrants experimental testing., (© Wildlife Disease Association 2023.)

The Northern Bobwhite (Colinus virginianus) is an economically important game bird within the Rolling Plains Ecoregion. Within this region, bobwhite is experiencing extreme cyclic population fluctuations which are resulting in a net decline in total population. It is suspected that within this region two helminth parasites, an eyeworm (Oxyspirura petrowi) and a cecal worm (Aulonocephalus pennula), are contributing to this phenomenon. However, this has been difficult to study as the primary mode of investigation would be the deployment of anthelmintic treatment. Unfortunately, no registered treatments for wild bobwhite currently exist. Thus, utilizing an anthelmintictreatment for wild bobwhite would require registration of that treatment with the U.S. Food and Drug Administration (FDA). As bobwhite are game birds that are hunted, they are considered food-producing animals to the FDA, and as such require the assessment for the withdrawal of the drug residues to be assessed for human food safety. In this study, we optimized and validated a bioanalytical method for the quantification of fenbendazole sulfone in bobwhite following the U.S. FDA Center for Veterinary Medicine Guidance for Industry #208 [VICH GL 49 (R)] for assessment of fenbendazole sulfone drug residue in Northern bobwhite liver. The official method for quantifying fenbendazole sulfone in domestic chicken (Gallus gallus) was adapted for use in bobwhite. The validated method quantitation range is 2.5-30 ng/mL for fenbendazole with an average recovery of 89.9% in bobwhite liver., (© 2023 John Wiley & Sons Ltd.)

Grassland birds have been declining substantially for the past several years. Habitat loss, degradation, and fragmentation as well as climate change are all thought to be the main drivers of the decline. However, as the declines continue to accelerate, it is becoming imperative to examine other factors that may contribute to population fluctuations. The nematodes Oxyspirura petrowi, Aulonocephalus pennula, and Physaloptera sp. are commonly found infecting northern bobwhite (Colinus virginianus), a game species of economic importance, and all 3 nematodes use insects as an intermediate host. Here we used polymerase chain reaction techniques to determine the occurrence of the 3 nematodes in 7 insect orders to uncover epidemiological patterns of the greatest potential for transmission to northern bobwhite. Insects were collected from March through September using sweep nets and pitfall traps. An R × C chi-squared test with Monte Carlo simulation was used to determine differences in the occurrence of the parasites across taxa and time. The results of the statistical analysis showed the nematodes are predominantly found in the order Orthoptera, and A. pennula and Physaloptera sp. showed epidemiological patterns in insects. However, no such pattern was observed with O. petrowi. An explanation for the lack of epidemiological pattern in O. petrowi is proposed and the diversity of known insect hosts of the 3 nematodes is increased., (© American Society of Parasitologists 2023.)

Populations of northern bobwhites (Colinus virginianus; hereafter bobwhite) have been declining across their geographic range in North America, prompting consideration of the role parasites may play. We conducted this study to learn about the helminth fauna in South Texas, a region that supports a sustainable bobwhite population. Helminths were examined from 356 bobwhites collected during the 2014-2015 (n = 124) and 2015-2016 (n = 232) hunting seasons, when increasing trends in precipitation were observed in comparison with the previous two years. Ten helminth species were found, consisting of 14,127 individuals. Of these, all are heteroxenous parasites and three are pathogenic (Dispharynx nasuta, Tetrameres pattersoni and Oxyspirura petrowi). Aulonocephalus pennula numerically dominated the component community (81% prevalence, 99% of the total helminths found), whereas each of the remaining species occurred rarely (≤9% prevalence) and contributed few individuals (≤0.4%) to the helminth community. Prevalence and abundance of A. pennula were not influenced by host age, sex or body mass, but abundance was higher during the 2014-2015 than the 2015-2016 hunting season. Our findings indicate that the helminth community in bobwhites from South Texas can vary during long-term, highly variable precipitation conditions and these communities are more similar to those found in the Rolling Plains of Texas than those found in the eastern part of the bobwhite's geographic range in the US.

The Northern bobwhite quail (Colinus virginianus) is a popular game bird that has been experiencing a well-documented decline throughout Texas since the 1960s. While much of this decline has been attributed to habitat loss and fragmentation, recent studies have identified other factors that may also contribute to decreasing quail populations. Parasites, in particular, have become increasingly recognized as possible stressors of quail, and some species, particularly the eyeworm (Oxyspirura petrowi) and cecal worm (Aulonocephalus pennula) are highly prevalent in Texas quails. Eyeworm infection has also been documented in some passerines, suggesting helminth infection may be shared between bird species. However, the lack of comprehensive helminth surveys has rendered the extent of shared infection between quail and passerines in the ecoregion unclear. Thus, helminth surveys were conducted on bobwhite, scaled quail (Callipepla squamata), Northern mockingbirds (Mimus polyglottos), curve-billed thrashers (Toxistoma curvirostre), and Northern cardinals (Cardinalis cardinalis) to contribute data to existing parasitological gaps for birds in the Rolling Plains ecoregion of Texas. Birds were trapped across 3 counties in the Texas Rolling Plains from March to October 2019. Necropsies were conducted on 54 individuals (36 quail and 18 passerines), and extracted helminths were microscopically identified. Nematode, cestode, and acanthocephalan helminths representing at least 10 helminth species were found. Specifically, A. pennula and O. petrowi had the highest prevalence, and O. petrowi was documented in all of the study species. This research adds to the body of knowledge regarding parasitic infections in quail and passerines of the Rolling Plains ecoregion and highlights the potential consequences of shared infection of eyeworms among these bird species., (© American Society of Parasitologists 2021.)

Recently, the heteroxenous eyeworm, Oxyspirura petrowi, has gained attention due to its prevalence in the declining game bird, Northern bobwhite ( Colinus virginianus ), but the intermediate hosts of many nematodes remain unknown. However, identifying the intermediate host of O. petrowi with traditional techniques would be difficult and time-consuming, especially considering there are more than 80 potential orthopteran hosts just in Texas. To screen a large number of samples quickly and effectively, primers for nested PCR (nPCR) were developed using the internal transcribed spacer 1 (ITS1) region. Then the nPCR was used to identify which of the 35 species collected from the Order Orthoptera were potential intermediate hosts of O. petrowi . With this technique, 18 potential intermediate hosts were identified. Later, we collected live specimens of species that tested positive to confirm the presence of larvae, but larvae were not found in the live specimens, nor in the extra tissue of the species that had tested positive for O. petrowi DNA. Despite this, this study demonstrated that nPCR is more sensitive than traditional techniques and can be a valuable tool in determining the intermediate hosts of parasites.

Background: Oxyspirura petrowi (Spirurida: Thelaziidae), a heteroxenous nematode of birds across the USA, may play a role in the decline of the northern bobwhite (Colinus virginianus) in the Rolling Plains Ecoregion of West Texas. Previous molecular studies suggest that crickets, grasshoppers and cockroaches serve as potential intermediate hosts of O. petrowi, although a complete study on the life-cycle of this nematode has not been conducted thus far. Consequently, this study aims to improve our understanding of the O. petrowi life-cycle by experimentally infecting house crickets (Acheta domesticus) with O. petrowi eggs, feeding infected crickets to bobwhite and assessing the life-cycle of this nematode in both the definitive and intermediate hosts., Methods: Oxyspirura petrowi eggs were collected from gravid worms recovered from wild bobwhite and fed to house crickets. The development of O. petrowi within crickets was monitored by dissection of crickets at specified intervals. When infective larvae were found inside crickets, parasite-free pen-raised bobwhite were fed four infected crickets each. The maturation of O. petrowi in bobwhite was monitored through fecal floats and bobwhite necropsies at specified intervals., Results: In this study, we were able to infect both crickets (n = 45) and bobwhite (n = 25) with O. petrowi at a rate of 96%. We successfully replicated and monitored the complete O. petrowi life-cycle in vivo, recovering embryonated O. petrowi eggs from the feces of bobwhite 51 days after consumption of infected crickets. All life-cycle stages of O. petrowi were confirmed in both the house cricket and the bobwhite using morphological and molecular techniques., Conclusions: This study provides a better understanding of the infection mechanism and life-cycle of O. petrowi by tracking the developmental progress within both the intermediate and definitive host. To our knowledge, this study is the first to fully monitor the complete life-cycle of O. petrowi and may allow for better estimates into the potential for future epizootics of O. petrowi in bobwhite. Finally, this study provides a model for experimental infection that may be used in research examining the effects of O. petrowi infection in bobwhite.

Helminth parasites have been a popular research topic due to their global prevalence and adverse effects on livestock and game species. The Northern bobwhite (Colinus virginianus), a popular game bird in the USA, is one species subject to helminth infection and has been experiencing a decline of > 4% annually over recent decades. In the Rolling Plains Ecoregion of Texas, the eyeworm (Oxyspirura petrowi) and caecal worm (Aulonocephalus pennula) helminths are found to be highly prevalent in bobwhite. While there have been increasing studies on the prevalence, pathology, and phylogeny of the eyeworm and caecal worm, there is still a need to investigate the bobwhite immune response to infection. This study utilizes previously sequenced bobwhite cytokines and toll-like receptors to develop and optimize qPCR primers and measure gene expression in bobwhite intramuscularly challenged with eyeworm and caecal worm glycoproteins. For the challenge experiments, separate treatments of eyeworm and caecal worm glycoproteins were administered to bobwhite on day 1 and day 21. Measurements of primary and secondary immune responses were taken at day 7 and day 28, respectively. Using the successfully optimized qPCR primers for TLR7, IL1β, IL6, IFNα, IFNγ, IL10, and β-actin, the gene expression analysis from the challenge experiments revealed that there was a measurable immune reaction in bobwhite in response to the intramuscular challenge of eyeworm and caecal worm glycoproteins.

One hundred and sixty-one northern bobwhites (Colinus virginianus; hereafter 'bobwhite') were examined from the Rolling Plains ecoregion of Texas and western Oklahoma from 2011 to 2013. Complete necropsies yielded 13 species, of which two are new host (Gongylonema phasianella) and region (Eucoleus contortus) records and three (Dispharynx nasuta, Tetrameres pattersoni and Oxyspirura petrowi) are known to cause morbidity and mortality. Of the species found, Aulonocephalus pennula commonly occurred, Oxyspirura petrowi was intermediate in prevalence, and the remaining species were rare. Species richness was similar compared to studies from the southeastern U.S., but higher than studies from the same region. In addition, 12 of the 13 species were heteroxenous helminths, supporting the theory that heteroxenous helminths in semi-arid regions are more successful than monoxenous helminths. Prevalence and abundance of A. pennula and O. petrowi were higher in adult bobwhites than in juveniles. Abundance of A. pennula and O. petrowi was higher at southern locations compared to northern locations in the study area. Our study is the first to provide a current assessment of the bobwhite helminth community across the Rolling Plains ecoregion of the U.S.

Aulonocephalus pennula is a heteroxenous nematode that commonly infects a declining game bird, the northern bobwhite quail (Colinus virginianus). There is a lack of information on the life cycle of A. pennula and the potential effects of infection on bobwhites. In order to better understand the life cycle of this parasite, various species from the order Orthoptera were collected from a field site in Mitchell County, Texas. Using polymerase chain reaction (PCR), nine potential intermediate hosts were identified from the 35 orthopteran species collected. Later, ten live specimens were collected to identify larvae within the potential intermediate hosts. Larvae were present in three of these and were sent for sequencing. Similarly, the presence of larvae was confirmed from extra tissues of samples identified as positive with PCR. This was the first study to document potential intermediate hosts, but future studies are needed to confirm that these species are capable of transmitting infection to bobwhite. However, this study demonstrates that PCR has increased sensitivity and may be a valuable tool when determining intermediate hosts.

Physaloptera spp. are common nematodes found in the stomach and muscles of mammals, reptiles, amphibians, and birds. Physaloptera spp. have a complicated life cycle with multiple definitive hosts, arthropod intermediate hosts, aberrant infections, and possible second intermediate hosts or paratenic hosts. For example, Physaloptera sp. larvae have been found within the tissues of wild northern bobwhite quail (Colinus virginianus), and it is suspected that quail may serve as paratenic or secondary hosts of these parasites. However, because it is not known what role quail play in the life cycle of Physaloptera spp. and descriptions of Physaloptera spp. larvae are limited, molecular tools may be beneficial when identifying these helminths. In this study, we generated primers using universal nematode primers and obtained a partial mitochondrial cytochrome oxidase 1 (COX 1) sequence. Morphological identification of Physaloptera sp. in bobwhite was confirmed via polymerase chain reaction (PCR), and a phylogenetic tree was constructed using the maximum likelihood method. BLAST analysis revealed a strong identity to other Physaloptera spp. and the phylogenetic tree placed all Physaloptera spp. in the same cluster. We also documented a marked increase in Physaloptera infections in bobwhite from 2017 to 2018, and the similarity of these parasites to Onchocerca volvulus and Wuchereria bancrofti may give insight into the increased prevalence we observed. This study demonstrates the usefulness of molecular techniques to confirm the identity of species that may lack adequate descriptions and provides new insight for the diagnosis and potentially overlooked significance of Physaloptera sp. infections of bobwhite in the Rolling Plains ecoregion of Texas.

The Northern bobwhite quail (Colinus virginianus) is an economically significant gamebird that has experienced a decline throughout the Rolling Plains ecoregion of Texas. Recent surveys of this area have revealed a high prevalence in eyeworm (Oxyspirura petrowi) and caecal worm (Aulonocephalus pennula) infection that may contribute to this decline. In order to further understand these parasites role in bobwhite populations, a time-, and cost-effective multiplex quantitative PCR (qPCR) assay was developed in this study to detect eyeworm and caecal worm infection through egg detection using the ITS2 and COX1 gene region, respectively. Method validation for the qPCR involved bobwhite fecal samples from the Rolling Plains as well as samples spiked with eyeworm, caecal worm, and bobwhite DNA. Results showed an observed increasing qPCR parasite egg detection with increasing worm burdens. Future uses with this assay can also provide insight to seasonal parasite infection and the life cycles of eyeworm and caecal worm., (Copyright © 2018 Elsevier B.V. All rights reserved.)

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., (© 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.)

Oxyspirura petrowi is a parasitic nematode that infects wild birds. This parasite has a broad host range, but has recently been reported in high prevalences from native Galliformes species in the United States. In order to better understand the impact O. petrowi has on wild bird populations, we developed a quantitative PCR protocol to detect infections in wild northern bobwhites (Colinus virginianus). We used paired fecal and cloacal swab samples from wild caught and experimentally infected northern bobwhites and matching fecal float data from experimentally infected birds to validate our assay. Overall we detected more positive birds from fecal samples than the paired cloacal swabs and there was strong agreement between the qPCR results from fecal samples and from fecal flotation (84%; κ = 0.69 [0.53-0.84 95% CI]). We also detected O. petrowi DNA in ten replicates of samples spiked with one O. petrowi egg. This qPCR assay is an effective assay to detect O. petrowi infections in wild birds. Our results suggest that fecal samples are the most appropriate sample for detecting infections; although, cloacal swabs can be useful for determining if O. petrowi is circulating in a population., Competing Interests: The authors have declared that no competing interests exist.

The Northern Bobwhite ( Colinus virginianus ) has declined across its range. The primary cause of this decline is thought to be habitat loss and fragmentation. However, there is speculation that factors such as parasites may play a role. South Texas recently was designated a Legacy Landscape of National Significance for Northern Bobwhite Conservation and is a region with some of the highest bobwhite densities in the US. Limited studies on bobwhite parasites have been conducted in this crucial landscape. We documented helminth parasites infecting bobwhites in South Texas, identified those that are known to be pathogenic to quail, documented pathologic responses to infection, and evaluated infections related to host intrinsic and extrinsic factors. We examined 209 bobwhites and found nine species of helminths including two known to cause tissue damage in bobwhites: Tetrameres pattersoni and Oxyspirura petrowi. The cecal nematode Aulonocephalus pennula was numerically dominant and had the greatest prevalence, intensity, and abundance. Prevalence and abundance of A. pennula were significantly greater in adult than juvenile bobwhites, whereas host sex was not an important factor. Prevalence of A. pennula was significantly greater during the 2012-13 hunting season than the 2013-14 season. The abundance of A. pennula also was significantly greater in bobwhites with greater mass within each age cohort. This research provides insight regarding the factors that influence helminth infections in bobwhites from South Texas and highlights the importance of broad-scale surveys when assessing helminth infections across large regions.

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.

This paper highlights a general problem, namely that host genome sequences can easily be contaminated with parasite sequences, thus careful isolation of genetic material and careful bioinformatics analysis are needed in all cases. Two recently published genomes are shown here to be contaminated with sequences of apicomplexan parasites which belong to the Sarcocystidae family. Sequences of the characteristic apicomplexan organelle, the apicoplast, were used as queries in BLASTN searches against nucleotide sequences of various animal groups looking for possible contamination. Draft genomes of a bird, Colinus virginianus (Halley et al., 2014), and a bat, Myotis davidii (Zhang et al., 2013) were found to contain at least six and 17 contigs, respectively, originating from the apicoplast of an apicomplexan species, and other genes specific to this phylum can also be found in the published genomes. Obviously, the sources of the genetic material, the muscle and the kidney of the animals, respectively, contained the parasitic cysts. Phylogenetic analyses using 18S rRNA and internal transcribed spacer 1 genes show that the parasite contaminating C. virginianus is a species of Sarcocystis related to ones known to cycle between avian and mammalian hosts. In the case of M. davidii it belongs to the Nephroisospora genus, the only member of which, Nephroisospora eptesici, has been recently identified from the kidney of big brown bats (Eptesicus fuscus)., (Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.)

Northern Bobwhites (Colinus virginianus) have been in decline throughout the southeastern US. Prevalence of Trichomonas gallinae in wild bobwhites is unknown, although T. gallinae caused morbidity and mortality in experimentally infected bobwhites. Many species of Columbidae (pigeons and doves) in Texas are hosts to T. gallinae. Bobwhites potentially may become exposed to this protozoan through supplemental feed or water sources contaminated by columbids infected with T. gallinae. All of 506 bobwhites collected in Oklahoma and Texas, 2011-13, were PCR negative for T. gallinae. These data suggest T. gallinae is not contributing to the population decline of bobwhites in this region.

The effects of Oxyspirura petrowi infections in northern bobwhites ( Colinus virginianus ) are not well understood. While studies have reported O. petrowi infections, none has histopathologically examined the eye surface and intraorbital glands to assess cellular-level impacts associated with infection. This study is the first to document the histopathology associated with O. petrowi infections. Oxyspirura petrowi occurred on the eye surface as well as in the conjunctiva, lacrimal ducts, lacrimal glands, and Harderian glands. Histopathology showed infections of O. petrowi caused cellular damage to these tissues, scarring and interstitial keratitis of the cornea, and acinar atrophy of the Harderian gland.

Northern bobwhite ( Colinus virginianus ) have experienced a dramatic decline in West Texas over the last 3 yr, and investigations are underway to evaluate the role of parasites in this decline. One of the key parasites being investigated is the eyeworm (Oxyspirura petrowi). Live eyeworms were extracted from both live and dead northern bobwhites, and in vitro survival was tested using 10 liquid media. Eyeworms placed in an egg white and physiological saline solution lived for at least 36 days. Live O. petrowi placed into the eyes of uninfected pen-raised bobwhites were monitored for 21 days to demonstrate successful transfer. Eyeworm behavior during feeding, mating, and development were monitored. This study is important to research that requires "banking" of live O. petrowi from wild-captured definitive hosts for life history studies and assessing the impact of O. petrowi on host individuals.

Background: Oxyspirura 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., Results: We 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., Conclusions: The 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.

Coccidiosis is an important disease in captive gamebirds, including northern bobwhites (Colinusvirginianus). Three Eimeria species, Eimeria lettyae, Eimeria dispersa, and Eimeria colini, have been described in bobwhites. Distinguishing the various Eimeria spp. is often problematic because of similarity in oocyst morphology and site of infection and thus requires live bird infections to distinguish between the coccidian species. To aid in identification and diagnosis, PCR specific primers were generated against the internal transcribed spacer region 1 (ITS-1) of the ribosomal RNA gene using sequences obtained from coccidian-positive samples collected from diagnostic cases or litter from captive bobwhites. Three distinct Eimeria spp. were detected. Species-specific primers were constructed and used to survey the prevalence of the species in 31 samples collected from 13 states. The primers survey results identified E. lettyae, E. dispersa, and Eimeria sp. in 20 (64.5%), 22 (71%), and 29 (93.5%) of the samples, respectively. Mixed infections were common: 13 (41.9%) samples had 3 Eimeria spp., 14 (45.2%) had 2 spp., and 4 (12.9%) samples had only 1 species. The species were widely distributed over the area sampled and were not associated with the age of the flock.

Inoculation of northern bobwhite quail ( Colinus virginianus ) with low doses of Eimeria lettyae oocysts stimulates a protective immune response, suggesting immunization may be an option for controlling coccidiosis. However, the oocyst production of inoculated birds could be considerable, leading to subsequent outbreaks. To determine the oocyst production following inoculation with E. lettyae, we orally infected 12-wk-old bobwhites with 100, 1,000, or 10,000 sporulated oocysts. Fecal materials were collected on days 5-9 post-inoculation, and total oocyst production was counted in McMaster chambers. Oocyst production/bird was 49.75, 89.5, and 436 × 10(6) for 100, 1,000, or 10,000 oocysts administered, respectively. Estimated oocysts produced/oocyst administered was 49.75, 8.95, and 4.36 × 10(4) for 100, 1,000, or 10,000 oocysts administered, respectively. These findings not only illustrate the crowding effect of larger oocyst inocula but also illustrate the fecundity of E. lettyae at low doses. This suggests that successful immunization of bobwhites against coccidiosis with live vaccines might require attenuated strains with reduced reproductive potential.

Parahaemoproteus lophortyx (formerly Haemoproteus lophortyx) is known to infect populations of bobwhite quail (Colinus virginianus) in California and to lead to considerable mortalities in these birds. Populations of bobwhite quail in Florida have never been surveyed for the presence of this parasite. The goal of this study was to determine whether P. lophortyx is present in populations of bobwhite quail in north Florida. To achieve this goal, blood was drawn from 294 bobwhite quail from 4 study sites in north Florida from 19 June 2007 to 1 August 2007. Blood smears were made, stained with Giemsa, and examined under x1,000 magnification for the presence of Parahaemoproteus lophortyx. No gametocytes were noted in any of the blood smears. Thirty randomly chosen samples were examined via polymerase chain reaction (PCR). This procedure may detect parasitemias too low to detect by microscopy. No PCR-positive samples were detected, however, adding support to the absence of hematozoa in Florida populations of bobwhite quail.

A pen-reared northern bobwhite and a domestic turkey were infected with a strain of Plasmodium hermani obtained originally from a wild turkey in southern Florida. Blood films from these 2 birds were positive microscopically for 188 and 370 days postinfection (PI), respectively. Culicine mosquitoes (Culex nigripalpus and C. salinarius) were blood fed on the bobwhite and the turkey at different times during the infection and used to transmit the malaria to other bobwhites and turkeys up to days 298 and 473 PI, respectively. It was concluded that in nature, P. hermani could remain in a chronic phase in avian hosts for a year, or longer, allowing survival of the parasite between seasons of mosquito transmission.

This report chronicles recurring outbreaks of Haemoproteus lophortyx infection in captive bobwhite quail. Clinically, the signs of infection included reluctance to move, ruffled appearance, prostration, and death. These signs were associated with parasitemia, anemia, and the presence of large megaloschizonts in skeletal muscles, particularly those of the thighs and back. The average cumulative mortality for flocks experiencing outbreaks was over 20%. In a typical outbreak, mortality rose when the birds were 5-6 wk of age, peaked in 8-to-10-wk-old quail, and declined rapidly when the quail were 9-11 wk old. Outbreaks occurred exclusively between the months of May and October, and warm weather was determined to be a risk factor for H. lophortyx mortality. This protozoan most likely overwinters in native California quail in the area and is transmitted to quail on the ranch by an insect vector that emerges in warm weather. Infection of the large population of naïve bobwhite quail on the ranch leads to amplification of H. lophortyx, resulting in epidemics in successive flocks.

An experiment to determine if wild Culex nigripalpus preferentially enter lard-can traps baited with chickens or bobwhite quail was conducted. A strong preference for the chicken-baited trap was observed. Further development of transmission models for St. Louis encephalitis virus in southern Florida should consider increased biting rates on sentinel chickens and the consequences for the interpretation of sentinel seroconversion data.

Because of limited access to the endangered Attwater's prairie chicken (Tympanuchus cupido attwateri), we used a related species, the northern bobwhite (Colinus virginianus), as a surrogate for disease evaluation. Free-living northern bobwhites (n = 62) on the Attwater Prairie Chicken National Wildlife Refuge (near Eagle Lake, Texas, USA) were examined during spring and fall 1993 for helminthic endoparasites and specific antibodies against the infectious agents responsible for nine infectious diseases. Trichostrongylus cramae, Raillietina sp., and Strongyloides avium were collected from 97, 44, and 32% of northern bobwhites examined, respectively. Dispharynx nasuta and Syngamus trachea also were found. No gross lesions due to parasites were observed. Specific antibody to Pasteurella multocida was found in 3 of 53 plasma samples. It is possible that potentially pathogenic species such as P. multocida, T. cramae, and D. nasuta could threaten sympatric Attwater's prairie chickens.

During a telemetry study conducted between 1993 and 1995 in east-central Kansas (USA) on northern bobwhite (Colinus virginianus) populations, a wild adult male quail was found with signs of disorientation and torticollis in August 1994 in Lyon County, Kansas. Based on histological and parasitological examination, it was determined that the bird was infected with larval nematodes of the genus Baylisascaris spp. This is the first known recorded case of Baylisascaris sp. in a wild game bird species.

Twenty-four 3-5-mo-old battery-hatched bobwhite quail were inoculated orally with 10(5) (ME 49 strain, group A, 6 birds), 10(4) (ME 49 strain, group B, 6 birds), 10(5) (GT-1 strain, group C, 6 birds), and 10(4) (GT-1 strain, group D, 6 birds) Toxoplasma gondii oocysts. One quail in group B died 18 days after inoculation (DAI) due to undetermined etiology. Two quail from group C and 1 quail from group D given GT-1 oocysts died of acute toxoplasmosis 6, 7, and 8 DAI, respectively; numerous T. gondii tachyzoites were found in lesions in visceral tissues. The surviving quail in group A and B were killed 106 DAI and those in groups C and D were killed 60 DAI. Toxoplasma gondii was isolated from pooled tissues of 4 of 5 quail in group B. Brains, hearts, and skeletal muscles from quail in groups A, C, and D were bioassayed individually in mice; T. gondii was isolated from the brains of all 6, hearts of 3, and skeletal muscles of 2 of the 6 quail in group A; from the brains of all 4, hearts of 1, and skeletal muscles of 2 of the 4 quail in group C; and from the brains of all 5, hearts of 1, and skeletal muscles of 3 of the 5 quail in group D. Toxoplasma gondii antibodies were found in sera of all 20 quail killed 60 or 106 DAI. Antibody titers detected in the modified agglutination test using whole tachyzoites were higher than in latex agglutination and indirect hemagglutination tests that used soluble antigens. Antibodies were not detected in a 1:4 dilution of 19 of 20 quail sera in the Sabin-Feldman dye test.

The red grouse (Lagopus lagopus scoticus) and northern bobwhite (Colinus virginianus) are parasitized by the cecal nematode, Trichostrongylus tenuis. Our objective was to determine if T. tenuis from red grouse is infective in bobwhites. We inoculated bobwhites with infective-stage T. tenuis larvae that originated from red grouse in northern England and bobwhites in Florida. We also inoculated domestic chickens with larvae from the same sources. None of the 6 bobwhites inoculated with larvae from red grouse became infected. Five of the 6 bobwhites inoculated with larvae of bobwhite origin became infected. All of the chickens were infected. At necropsy, lesions or inflammation of the ceca were not observed either in chickens or bobwhites. The results suggest that Trichostrongylus in red grouse and northern bobwhite are distinct species. Along with absence of gene flow, differences in transmission conditions and infrapopulation levels may have resulted in differences in host specificity.

Examination of 700 northern bobwhites (Colinus virginianus), 50 each February from 1971 through 1984, from Tall Timbers Research Station, Leon County, Florida, disclosed 15 species of helminth parasites. Nine species (Raillietina cesticillus, R. colinia, Aproctella stoddardi, Cheilospirura spinosa, Cyrnea colini, Dispharynx nasuta, Heterakis isolonche, Tetrameres pattersoni, and Trichostrongylus tenuis) generally were found on an annual basis and were considered characteristic components of the helminth fauna. Infrequently found species were Brachylecithum nanum, Rhabdometra odiosa, Capillaria sp., Gongylonema ingluvicola, H. gallinarum, and Oxyspirura matogrosensis. Intensities of C. colini and H. isolonche differed among host sex and age classes, and prevalences and/or intensities of A. stoddardi, C. spinosa, T. pattersoni, and T. tenuis differed between host age classes. Prevalences and/or abundances of seven species (R. cesticillus, R. colinia, C. spinosa, C. colini, H. isolonche, T. pattersoni, and T. tenuis) varied with bobwhite density, apparently because bobwhites were either the primary or only definitive host on the area. Two species (A. stoddardi and D. nasuta) did not vary with bobwhite density, apparently due to the buffering effect of a broad range of definitive hosts on the area. Prevalences and/or intensities of R. colinia, C. spinosa, and T. tenuis differed with agricultural fields status (cultivated versus fallow) suggesting that land use and its attendant habitat changes influenced transmission of these species. The occurrence of C. spinosa and T. pattersoni in individual bobwhites was not independent and was attributed to utilization of the same species of grasshoppers as intermediate hosts. Localized tissue damage and inflammation were associated with A. stoddardi, D. nasuta, C. spinosa, C. colini and T. pattersoni. Decreases in body weight in juvenile bobwhites were associated with increasing intensities of H. isolonche and T. tenuis. The observed relationships to bobwhite density and other variables are discussed with regard to known aspects of life histories of the nine most common species.

A new species of coccidium, Eimeria lettyae sp. n. (Protozoa: Eimeriidae) was recovered from feces of the northern bobwhite, Colinus virginianus (L.), from Pennsylvania and Florida. Oocysts measured 21.1 microns (16.4 to 25.8) by 17.2 microns (14.1 to 21.2); index (L/W ratio) = 1.22. Oocysts lacked a micropyle, residuum, and polar granules. Sporozoites penetrated the upper 1/2 of the villi, then moved to the lamina propria at the base of the villi. There were five asexual generations, all of which developed above the nucleus of the host cell. Meronts measured 9.4 X 7.0 microns, 18.6 X 11.2 microns, 11.8 X 10.1 microns, 7.1 X 6.2 microns, and 20.2 X 12.8 microns, respectively. These matured at 32, 40, 48, 56, and 72 hr postinoculation (PI) and contained 12, 50+, 24 to 36, 12 to 24, and 50+ merozoites, respectively. Infection was most intense in the duodenum although some gamonts were found in the ileum and ceca. The prepatent period was 88 to 91 hr PI. Sporulation time was 18 hr at 25 C. The peak of oocyst production was broad and extended from 4 days PI through 14 days PI. Oocysts were passed for at least 67 to 76 days PI. Eimeria lettyae sp. n. did not infect chickens (Gallus domesticus), domestic turkeys (Meleagris gallopavo), ring-necked pheasants (Phasianus cochicus), chukar partridge (Alectoris graeca), or Japanese quail (Coturnix coturnix). Immunizing bobwhite with E. lettyae sp. n. did not protect against challenge with E. dispersa. Immunizing bobwhites 25 times with 10(2) or 10(3) sporulated oocysts of E. lettyae did not entirely eliminate oocyst production following challenge with the same species.

Twenty-one species of ectoparasites representing 19 genera were collected from 481 bobwhite quail (Colinus virginianus) from nine areas in four southeastern states. Sixteen species, Amblyomma americanum, Haemaphysalis chordeilis, Haemaphysalis leporispalustris, Eutrombicula alfreddugesi alfreddugesi, Neoschoengastia americana, Boydaia colini, Pterolichus sp., Colinophilus wilsoni, Megninia sp., Apionacarus wilsoni, Colinoptes cubanensis, Menacanthus pricei, Colinicola numidiana, Gonoides ortygis and Oxylipeurus clavatus were previously known from bobwhites, whereas five species, Ixodes minor, Neotrombicula whartoni, Dermoglyphus sp., Microlichus sp. and Rivoltasia sp. (near coturnicola) represented new host-parasite associations. Data are presented giving prevalence, geographic location, host age and numbers of quail infested with each species. Significant lesions were not associated with any species.

We collected 153 northern bobwhites (Colinus virginianus) over a 10-mo period from Tall Timbers Research Station near Tallahassee, Florida, USA. Five species of gastrointestinal helminths were encountered commonly (greater than 30% prevalence): Cyrnea colini, Raillietina cesticillus, R. colinia, Heterakis isolonche, and Trichostrongylus tenuis. Other helminths included Brachylaima sp., Rhabdometra odiosa, Mediorhynchus papillosis, Cheilospirura spinosa, Dispharynx nasuta, Gongylonema ingluvicola, and Tetrameres pattersoni. During the intervening 15 yr since the last year-round study of this population of birds, C. spinosa and T. pattersoni have declined markedly, and Strongyloides sp. probably has become extinct locally. Prevalence and intensity seem more likely to fluctuate in parasite species that have complex life cycles.

The life cycle and morphology of a previously undescribed species of Cryptosporidium isolated from commercial broiler chickens is described. The prepatent period for Cryptosporidium baileyi n. sp. was three days post oral inoculation (PI) of oocysts, and the patent period was days 4-24 PI for chickens inoculated at two days of age and days 4-14 for chickens inoculated at one and six months of age. During the first three days PI, most developmental stages of C. baileyi were found in the microvillous region of enterocytes of the ileum and large intestine. By day 4 PI, most parasites occurred in enterocytes of the cloaca and bursa of Fabricius (BF). Mature Type I meronts with eight merozoites first appeared 12 h PI and measured 5.0 x 4.9 micrometers. Mature Type II meronts with four merozoites and a large granular residuum first appeared 48 h PI and measured 5.1 x 5.1 micrometers. Type III meronts with eight short merozoites and a large homogeneous residuum first appeared 72 h PI and measured 5.2 x 5.1 micrometers. Microgamonts (4.0 x 4.0 micrometers) produced approximately 16 microgametes that penetrated into macrogametes (4.7 x 4.7 micrometers). Macrogametes gave rise to two types of oocysts that sporulated within the host cells. Most were thick-walled oocysts (6.3 x 5.2 micrometers), the resistant forms that passed unaltered in the feces. Some were thin-walled oocysts whose wall (membrane) readily ruptured upon release from the host cell. Sporozoites from thin-walled oocysts were observed penetrating enterocytes in mucosal smears. The presence of thin-walled, autoinfective oocysts and the recycling of Type I meronts may explain why chickens develop heavy intestinal infections lasting up to 21 days. Oocysts of C. baileyi were inoculated orally into several animals to determine its host specificity. Cryptosporidium baileyi did not produce infections in suckling mice and goats or in two-day-old or two-week-old quail. One of six 10-day-old turkeys had small numbers of asexual stages only in the BF. Four of six one-day-old turkeys developed mild infections only in the BF, and sexual stages of the parasite were observed in only one of the four. All seven one-day-old ducks and seven two-day-old geese developed heavy infections only in the BF with all known developmental stages present.

Two nematode species, one acanthocephalan species, and unidentified cestodes were recovered from a total of 481 northern bobwhites (Colinus virginianus) collected from January 1982 to December 1983 in southern Texas. The nematodes Aulonocephalus lindquisti and Trichostrongylus tenuis varied in prevalence with month and locality. Mediorhynchus papillosis was recovered from only two birds. Monthly and yearly rainfall patterns were not correlated with endoparasite intensity and prevalence, which indicates that fluctuations of populations of northern bobwhites in Texas may be caused by factors other than changes in prevalence and intensity of endoparasites.

Two noncentrifugal and 5 centrifugal flotation methods for the recovery of infective Baylisascaris procyonis eggs from contaminated soil were evaluated after an epizootic of fatal cerebrospinal nematodiasis in bobwhites. All involved the use of inexpensive, readily available materials and routine procedures. In all but 1 of the methods, sizes of the soil samples were 30 g; in 1 centrifugal method, the sample size was 1 g. The centrifugal methods included various combinations of (i) anionic detergent (Tween) pretreatment of the soil, (ii) 3 X washing of the sediment, (iii) NaNO3 or ZnSO4 flotation solution, and (iv) resuspension and reexamination of the sediment. By the 30-g sample centrifugal methods, significantly more eggs (av 251 to 448) were recovered than by the noncentrifugal methods (av 7 and 12) or the 1-g sample method (av 44). In the most efficacious method, the combination of Tween pretreatment, washed sediment, NaNO3 flotation solution, and resuspension/reexamination of the sediment was used. This method was tested against the 1-g sample method on soil from a naturally occurring infection of Toxocara cati visceral larva migrans in a child. On initial examination of 5 areas, 3 to 10 eggs were recovered by the 30-g sample method vs 0 eggs by the 1-g sample method. Using sandbox soil and 10 replicates each, recoveries by the 30-g sample method averaged 9.2 eggs/replicate (range 5 to 12) and those by the 1-g sample method, 0.1 eggs (range 0 to 1).

Helminthologic examination of 120 adult and 65 juvenile bobwhites (Colinus virginianus) from Leon County, Florida, during a one-year period revealed seven common (> 30% prevalence) species including Raillietina cesticillus, R. colinia, Cheilospirura spinosa, Cyrnea colini, Heterakis bonasae, Tetrameres pattersoni, and Trichostrongylus tenuis. Less frequently found helminths included Hymenolepis sp., Rhabdometra odiosa, Mediorhynchus papillosis, Aproctella stoddardi, Dispharynx nasuta, Gongylonema ingluvicola, Strongyloides avium, and Subulura sp. Juvenile bobwhites had acquired infections of 6 of the 7 common helminths by July and all seven species by August. A shift from a predominance of immature to mature parasites was noted with increasing age of juvenile bobwhites followed both linear and non-linear (plateau effect) trends when compared to age of the host. By mid-winter total helminth burdens of juvenile birds approached levels in adults. Cheilospirura spinosa, C. colini and T. pattersoni showed marked peaks in transmission between June and September. The two cecal nematodes, H. bonasae and T. tenuis, showed seasonal shifts in relative abundance with H. bonasae predominating during the summer and T. tenuis predominating during the winter. Lesions attributable to helminths were rare and involved minimal tissue damage.

Sporulated oocysts of Eimeria lettyae were administered orally to 5-day-old or 18-day-old northern bobwhites (Colinus virginianus, L.). Five-day-old bobwhites were more susceptible based on higher mortality and reduced weight gain. A dose of 5 X 10(5) oocysts produced 25-43% mortality in 5-day-old bobwhites, but none in 18-day-old bobwhites. A dose of 1 X 10(6) oocysts/bobwhite produced 83-100% mortality in 5-day-old bobwhites, and 17-83% mortality in 18-day-old bobwhites. Body weight gain was reduced significantly with a dose of 1 X 10(5) oocysts or greater in 5-day-old bobwhites and with a dose of 5 X 10(5) oocysts or greater in 18-day-old bobwhites. Infection in all age groups reduced concentrations of plasma pigment and plasma protein, but did not affect packed cell volumes. No grossly visible lesions were present in the intestine although there was a shortening of the villi in the duodenum. In mature bobwhites, infection with E. lettyae did not cause mortality, but did reduce egg production and fertility.

The sporulated oocyst of Eimeria colini sp. n. is described from the bobwhite quail, Colinus virginianus. The broadly ellipsoid oocysts measured 24.8 micronm (22.4 to 28.0) by 20.9 micronm (17.9 to 22.4). The L/W ratio was 1.2 (1.1 to 1.4). An inconspicuous micropyle was present while an oocyst residuum and polar granule were absent. The oocyst walls were 1.4 micronm thick and covered with small, evenly spaced elevations. The sporocysts measured 14.2 micronm (12.3 to 14.5) by 8.4 micronm (7.8 to 8.9). A sporocyst residuum, small Stieda body and large substieda body were present. Ooocysts first appeared in the feces between 84 to 96 hr. Freshly-passed oocysts were completely sporulated by 48 hr at 25 C.