Publications by authors named "Kathryn Duncan"

Ticks represent important vectors of a number of bacterial and viral disease agents, owing to their hematophagous nature and their questing behavior (the process in which they seek new hosts). Questing activity is notably seasonal with spatiotemporal dynamics that needs to be understood in detail as part of mediating and mitigating tick-borne disease risk. Models of the geography of tick questing activity developed to date, however, have ignored the temporal dimensions of that behavior; more fundamentally, they have often not considered the sampling underlying available occurrence data.

View Article and Find Full Text PDF
Article Synopsis
  • - Intestinal parasites, especially Dipylidium caninum, are prevalent in U.S. dogs, but traditional fecal flotation methods often miss these infections; incorporating coproantigen testing significantly improves detection rates.
  • - A study examining fecal samples from 877 dogs revealed that D. caninum infection was identified in 5.6% using a combination of tests, with higher prevalence in shelter dogs compared to pets, highlighting varying detection based on demographics and geographic areas.
  • - The study also found that using coproantigen testing and other methods, like PCR of perianal swabs, could better identify not only D. caninum but also other intestinal parasites, suggesting a need for more advanced diagnostic practices in veterinary medicine.
View Article and Find Full Text PDF

Background: Transmission of canine heartworm (Dirofilaria immitis) from infected to naïve dogs is dependent on successful mosquito feeding and survival.

Methods: To determine whether treating heartworm-infected dogs with fluralaner (Bravecto) limits the survival of infected mosquitoes, and potentially the transmission of D. immitis, we allowed female mosquitoes to feed on microfilaremic dogs and evaluated mosquito survival and infection with D.

View Article and Find Full Text PDF

Although ticks are known vectors of pathogens across a range of hosts, there is limited research on emerging tick-borne diseases of horses in the United States. Tick surveys from other regions suggest Rickettsia spp. and Ehrlichia spp.

View Article and Find Full Text PDF
Article Synopsis
  • - The study aimed to establish reference intervals for radial joint orientation angles in small-breed dogs and compare them to previously reported angles for medium- and large-breed dogs.
  • - Radiographs of 30 small-breed dogs were analyzed to determine various radial angles, revealing specific mean values and standard deviations for these measurements.
  • - Notable differences were found in some joint angles when compared to medium- and large-breed dogs, providing valuable reference data that can assist in planning corrective surgeries for radial angular limb deformities in small-breed dogs.
View Article and Find Full Text PDF

As tick-borne diseases continue to increase across North America, current research strives to understand how the tick microbiome may affect pathogen acquisition, maintenance, and transmission. Prior high throughput amplicon-based microbial diversity surveys of the widespread tick Dermacentor variabilis have suggested that life stage, sex, and geographic region may influence the composition of the tick microbiome. Here, adult D.

View Article and Find Full Text PDF
Article Synopsis
  • Pathogenic variants in the BRCA1 gene significantly increase the risk of hereditary breast and ovarian cancer, with many individuals identified carrying variants of uncertain significance (VUSs) through genetic testing.
  • The study assessed 2,271 and 1,427 BRCA1 variants for their roles in homology-directed repair (HDR) and cisplatin resistance (CR) using multiplexed DNA repair assays, revealing high consistency in results.
  • Findings indicate that functional characteristics of these variants align with known clinical significance, providing valuable resources for understanding BRCA1 VUSs and their impact on tumor suppression.
View Article and Find Full Text PDF

In the United States, and are considered key vectors for , the causative agent of Rocky Mountain spotted fever. Through regional surveillance, a wide diversity of spp. have been documented in , and spp.

View Article and Find Full Text PDF

Background: Ticks are common on horses, but recent publications characterizing equine tick infestations in North America are lacking.

Methods: To further understand attachment site preferences of common ticks of horses, and to document the seasonality of equine tick infestation in northeastern Oklahoma, horses from eight farms were evaluated twice a month over a 1-year period. Each horse was systematically inspected beginning at the head and moving caudally to the tail.

View Article and Find Full Text PDF

Case Description: An 8-year-old spayed female Shih Tzu crossbreed dog (dog 1) and a 13-year-old neutered male Miniature Fox Terrier (dog 2) were evaluated for removal of neoplasms involving both the frontal lobe and olfactory bulb.

Clinical Findings: Physical examination revealed decreased menace response and behavioral changes in both dogs. For dog 1, neuroanatomic localization of the lesion was the left forebrain region; for dog 2, neuroanatomic localization of the lesion was the right forebrain region.

View Article and Find Full Text PDF

Throughout North America, Dermacentor spp. ticks are often found feeding on animals and humans, and are known to transmit pathogens, including the Rocky Mountain spotted fever agent. To better define the identity and distribution of Dermacentor spp.

View Article and Find Full Text PDF

Dermacentor albipictus, a common one-host tick of large animals in North America, is most often reported from moose (Alces alces) and is rarely implicated as a parasite of cats and dogs. From 2018 to 2020, 4 dogs and 4 cats from United States and 3 dogs from Canada were infested with D. albipictus.

View Article and Find Full Text PDF

Background: The rapid growth in off-leash dog parks provides opportunity for canine socialization activities but carries risk of exposure to intestinal parasites. This study assessed the prevalence of these infections in dogs visiting off-leash dog parks.

Methods: Fresh defecations were collected from dogs visiting parks in 30 metropolitan areas across the USA.

View Article and Find Full Text PDF

The Asian longhorned tick, Haemaphysalis longicornis, was only recently recognized in North America and has since been identified on a wide range of domestic and wild animal hosts in multiple states throughout the eastern United States. An H. longicornis nymph was submitted for identification from a dog in central Virginia, USA.

View Article and Find Full Text PDF

Domestic dogs commonly harbor intestinal parasites in Oklahoma and throughout the world. We tested fecal samples from dog parks to determine the prevalence of intestinal parasites and reported use of parasite control in park-attending dogs and assess potential health risks posed by fecal contamination of public dog parks in this region. Fecal samples (n = 359) were collected from five public access dog parks in central Oklahoma from February to July 2019.

View Article and Find Full Text PDF

Background: A variety of tick species infest dogs and cats in North America. Although most of these species also readily feed on people, national data regarding the species and abundance of ticks on dogs and cats are lacking. Here we report a large-scale study of ticks from dogs and cats in the USA over a 12-month period.

View Article and Find Full Text PDF

The BARD1 protein, which heterodimerizes with BRCA1, is encoded by a known breast cancer susceptibility gene. While several BARD1 variants have been identified as pathogenic, many more missense variants exist that do not occur frequently enough to assign a clinical risk. In this paper, whole exome sequencing of over 10,000 cancer samples from 33 cancer types identified from somatic mutations and loss of heterozygosity in tumors 76 potentially cancer-associated BARD1 missense and truncation variants.

View Article and Find Full Text PDF