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American trypanosomiasis (Chagas disease) is caused by the flagellated protozoan Trypanosoma cruzi (T. cruzi), a zoonotic parasite found in meso-mammal species in South Texas, USA. Chagas disease is of growing concern in vertebrate species, and not well-understood. Protocols for detection of mammalian T. cruzi infection are available, but have poor specificity and sensitivity and require a secondary disease confirmation assay. The utility of combining an antibody-based and a DNA-based assay for simultaneous T. cruzi infection detection has been largely underexplored. Our objectives were to evaluate commercially available single-use Chembio Diagnostics, Inc. DPP® (Dual Path Platform) immunochromatographic rapid detection assay device for the detection of antibodies to T. cruzi in meso-mammal species as compared with standard polymerase chain reaction (PCR) testing for T. cruzi DNA. In May and June 2016, we tested the device on whole blood serum from 50 meso-mammals including raccoons (Procyon lotor), Virginia opossums (Didelphis virginiana), fox squirrels (Sciurus niger), rock squirrels (Otospermophilus variegatus), a striped skunk (Mephitis mephitis), a nine-banded armadillo (Dasypus novemcinctus), and a ringtail (Bassariscus astutus) in central Texas. Our results showed the Chembio Diagnostics, Inc. DPP® immunochromatographic rapid detect assay system identified infection in 74% of meso-mammals that tested positive by PCR. This testing device shows promise as an effective first-line T. cruzi antibody detection device to mass screen for disease infection in meso-mammals.

Sylvilagus palustris hefneri (Lower Keys Marsh Rabbit [LKMR]) is an endangered subspecies of marsh rabbit found only in the Lower Florida Keys. In September 2017, Hurricane Irma was measured as a Category 4 storm when it passed through the center of the LKMR range causing significant damage to human infrastructure and natural habitats. To assess the impact of Hurricane Irma to LKMR and its habitat, we compared pre- and post-hurricane monitoring data. Overall, 82% of LKMR habitat patches were abandoned, the average number of pellets per sampling plot decreased 94%, and average patch pellet density decreased by 84% following Hurricane Irma. Generally, pellets were found in plots with greater open cover, an intermediate amount of herbaceous and woody cover, and areas with more standing water post-Hurricane Irma. We also observed a slight decrease in signs of Procyon lotor (Raccoon) and Didelphis virginiana (Virginia Opossum). The decrease in rabbit pellets detected after Hurricane Irma is likely attributed to both direct mortality from the storm and flooding, as well as indirect mortality from the loss of critical, salt-sensitive herbaceous cover. Because climate-change models suggest increases in future flooding and hurricane frequency, we recommend that wildlife managers continue to closely monitor the recovery of LKMR populations and their habitat to determine if more active management actions (e.g., habitat remediation, translocations, or captive breeding) are necessary.

Scat of meso-mammals provides nutrients to cave-obligate species. If there are too few nutrient inputs, cave-obligate species have no resources, but too much and caves are invaded by terrestrial species. Our goal for this project was to determine what combination of variables most influence meso-mammal cave use by building a multinomial regression model using data collected from cave entrances in central Texas. Variables of importance in our model relate to cave accessibility, including the raccoons' (Procyon lotor) and Virginia opossums' (Didelphis virginiana) greater dexterity, and the added bulk from the North American porcupine's (Erethizon dorsatum) quills. Our model can be used to predict and manage meso-mammal cave use in central Texas. This will be especially useful in this region because North American porcupine have only recently expanded their range into central Texas and their prolific nutrient inputs, previously absent from the ecosystem, could endanger cave-obligate species.

The status of endangered Odocoileus virginianus clavium (Key Deer) on outer islands of Florida was unknown following several recent population declines. In response, we opportunistically monitored the western extent of the current range of Key Deer in Flordia using cameras and in-person observations to determine deer presence. We found evidence of Key Deer on islands at the far western edge of their current range such as Lower Sugarloaf Key, Saddlebunch Keys, Boca Chica Key, and the first documented occurrence of Key Deer on East Rockland Key. We recommend more intensive monitoring to determine the extent of the current range use and to calculate a range-wide abundance estimate.

We studied Greater Roadrunners' (Geococcyx californianus) habitat use during spring and summer of 2011 in the Red Rolling Plains of west Texas. We captured 10 roadrunners (one male and nine females) and fitted each with a 10-g backpack style radio-transmitter. Roadrunners were relocated 2–4 times per week from February–August. We used these data to build a logistic regression model to better understand the vegetative and topographic features important to roadrunners during the nesting season. The initial data set consisted of 30 random and 30 used locations. The best model showed both percent rock and percent litter to be higher at used locations and correctly classified 88% of the sites. Evaluation of the model with an additional 30 random and 30 used locations maintained significance of both the model and variables and correctly classified 83% of sites. Both variables were associated with the location's mesa ridge slopes. Litter dominated locations under shrubs on the ridge tops and slopes and likely provided security from predators, nest sites, and relief from extreme summer temperatures. Percent rock cover characterized locations on ridge tops and slopes which provided perch sites, travel lanes, and foraging sites where the roadrunners could find basking prey.

Little is known of the greater roadrunner's (Geococcyx californianus; roadrunner) ecology and many demographic questions are difficult to answer because of our inability to determine adult bird sex in the field. We collected measurements from live-captured roadrunners of known sex in Fisher County, Texas, USA, and from roadrunner specimens frommuseums and university biological collections from 2003 to 2012 to develop a predictive logistic regression model for adult sex determination. We measured 433 adult birds of which 80% (n= 346) were randomly chosen to build potential models. Our best model included the variable estimate bill depth, which was found to be larger in males and correctly classified 80% of the birds. We validated the model with the remaining 20% of measurements (n= 87) and correctly identified the sex of 85% of the birds. Because this model incorporated roadrunners from across their range, it provides an easy, inexpensive, accurate, and field-relevant methodology for sex determination of adult roadrunners at the point of capture.

We studied Greater Roadrunners' (Geococcyx californianus) habitat use during spring and summer of 2011 in the Red Rolling Plains of west Texas. We captured 10 roadrunners (one male and nine females) and fitted each with a 10-g backpack style radio-transmitter. Roadrunners were relocated 2-4 times per week from February-August. We used these data to build a logistic regression model to better understand the vegetative and topographic features important to roadrunners during the nesting season. The initial data set consisted of 30 random and 30 used locations. The best model showed both percent rock and percent litter to be higher at used locations and correctly classified 88% of the sites. Evaluation of the model with an additional 30 random and 30 used locations maintained significance of both the model and variables and correctly classified 83% of sites. Both variables were associated with the location's mesa ridge slopes. Litter dominated locations under shrubs on the ridge tops and slopes and likely provided security from predators, nest sites, and relief from extreme summer temperatures. Percent rock cover characterized locations on ridge tops and slopes which provided perch sites, travel lanes, and foraging sites where the roadrunners could find basking prey. Received 26 June 2013. Accepted 24 December 2013.

We studied Greater Roadrunner (Geococcyx californianus) habitat use during spring and summer 2011 on the Rolling Plains Quail Research Ranch in the Red Rolling Plains of west Texas. We captured 9 roadrunners (1 male, 8 females) and fitted each with a 10-g backpack-style radio-transmitter. We relocated roadrunners 2–4 times per week from February to August. Roadrunners used a mean minimum convex polygon home range of 43.0 ha, a 50% core range of 11.9 ha, and 33% overlap between adjacent home ranges. Home ranges were approximately half the size of those reported in a recent study of roadrunners in north Texas. Habitat selection ratios showed that roadrunners selected for ridge and grassland vegetation types and avoided bare ground and flatland vegetation types at both first- and second- but not third-order levels of selection. Similar results were documented for roadrunners in north Texas.

Florida Key deer (Odocoileus virginianus clavium) are an endangered subspecies of white-tailed deer endemic to the Lower Florida Keys. The New World screwworm (Cochliomyia hominivorax) infestation in July 2016 and Hurricane Irma on 10 September 2017 both caused the Key deer population to decline. Our objective was to estimate current Key deer population abundance using traditional distance sampling and a mark-resight methodology applicable for citizen scientist participation. For mark-resight efforts, deer were marked with hand sprayers using water-based livestock dye on Big Pine (BPK) and No Name keys (NNK). Biologists conducted road surveys between 9–13 March 2020 on BPK and NNK and collected data for mark retention, mark-resight, and distance calculations concurrently. Our mark-resight estimate (n = 748) was nearly 300 deer lower than the traditional distance estimate likely because of distance sampling's sensitivity to increased deer visibility along survey routes. Compared to historic data, our mark-resight population estimate indicated increased deer abundance compared to post-Hurricane Irma estimates (n = 573), but slightly below post-screwworm outbreak estimates (n = 860). Based on mark-retention data, we recommend all resight surveys be completed within 5 days of the first mark placement for the most dependable mark detection. We recommend our mark-resight method be used in future Key deer surveys as it is simple, efficient, and can bereliably completed with the assistance of volunteers therefore allowing for more regular monitoring.

Paraneoplastic cerebellar degeneration (PCD) is a rapidly progressive, immune-mediated syndrome characterized by the degeneration of Purkinje cells, often associated with the presence of antibodies targeting intracellular antigens within these cells. These autoantibodies are implicated in the induction of cytotoxicity, leading to Purkinje cell death, as demonstrated in in vitro models. However, the precise roles of antibodies and T lymphocytes in mediating neuronal injury remain a subject of ongoing research, with T cells appearing to be the main effectors of cerebellar injury. Notably, at least 50% of PCD cases involve anti-Yo autoantibodies, also referred to as anti-PCA1 (Purkinje cell antigen 1) antibodies, which specifically target cerebellar degeneration-related protein 2 (CDR2) and its paralogue, CDR2-like (CDR2L). Another recognized antigen is CDR 34, a 34 kDa Purkinje cell antigen characterized by tandem repeats and a B-cell epitope; its detection in non-cerebellar tissues necessitates further in situ hybridization studies. Onconeural antigens are expressed in both Purkinje cells and tumour cells, where they localize in the cytoplasm and associate with membrane-bound and free ribosomes, playing critical roles in regulating transcription and calcium homeostasis. Recent studies suggest that the breakdown of immune tolerance is linked to genetic alterations in tumour cell antigens, leading to the formation of neoantigens that can elicit autoreactive T cells, which may underscore the function of Yo antibodies. In vitro studies indicate that anti-Yo antibodies can induce cell death independent of T lymphocytes. The disease progresses by initial lymphocytic infiltration, followed by a rapid loss of Purkinje cells without significant inflammation. However, in vivo models showcase that anti-Yo PCD is primarily T-cell mediated, with antibodies serving as biomarkers rather than direct effectors of neuronal death. This review examines the mechanisms underlying PCD, focusing on the roles of CDR2 and CDR2L in tumour development and their potential role in the degeneration of cerebellar Purkinje neurons. A comprehensive understanding of these processes is essential for advancing diagnostic, prognostic, and therapeutic strategies for PCD and associated malignancies.