Equine attachment site preferences and seasonality of common North American ticks: Amblyomma americanum, Dermacentor albipictus, and Ixodes scapularis

Abstract

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. Attachment sites of ticks were recorded and all ticks collected were identified to species and stage. Results Horses (26 males and 62 females) enrolled in the study ranged in age from 1 to 23 years (mean = 12, 95% CI 11–13). A total of 2731 ticks were collected; 84.1% (74/88) of the horses were infested (median = 3 ticks) at one or more examinations. Five tick species were identified, including Amblyomma americanum (78.2%; 2136/2731), Ixodes scapularis (18.2%; 497/2731), Dermacentor albipictus brown variant (2.6%; 71/2731), Dermacentor variabilis (0.7%; 20/2731), and Amblyomma maculatum (0.3%; 7/231). Most ticks were adults (83.6%; 2282/2731), but immature A. americanum (436/2136; 20.4%), D. albipictus (12/71; 16.9%), and A. maculatum (n = 1) were occasionally recovered. Amblyomma americanum were most often attached to the inguinal area, and I. scapularis and D. albipictus were most commonly found on the chest and axillary region (P < 0.0001). Ticks were found on horses in every month of the year. The largest number of ticks (638/2731; 23.4%) were collected in May (P < 0.0001). Amblyomma americanum, primarily immature, was the only tick recovered in September, I. scapularis and D. albipictus predominated October through February, and both A. americanum and I. scapularis were common in March. In the warmer months, April through August, A. americanum was the most common tick, followed by D. variabilis and A. maculatum. Conclusions This research confirms that ticks common on horses in North America have attachment site preferences and that ticks infest horses in Oklahoma throughout the year, including during the winter. Additional research is warranted to fully understand the risk these infestations pose to equine health. Graphical abstract

A Review of Commercial Metarhizium- and Beauveria-Based Biopesticides for the Biological Control of Ticks in the USA

“…Product tests in the laboratory on other tick species— Dermacentor albipictus (Packard), Dermacentor reticulatus (Fabricius), Ixodes ricinus (L.), Rhipicephalus sanguineus sensu lato, and Rhipicephalus ( Boophilus ) microplus (Canestrini)—also demonstrated high mortality under high temperature and humidity conditions (>80%RH) ( Table 4 ). Dermacentor albipictus larvae, a one-host tick that parasitizes ungulates like cattle, horses, and moose [ 35 , 36 , 37 ] has received the most attention. Although 100% mortality is achievable in vitro after three weeks when immersed or sprayed, broadcast applications of a granular formulation achieved a reduced level of mortality (89%).…”

Human attachment site preferences of ticks parasitizing in New York

“…The attachment site of ticks has been studied in the context of both animal and human tick preference. In Oklahoma, a study of horses indicated that A. americanum preferentially bites the inguinal area, while I. scapularis and D. albipictus , the moose-tick, primarily bite the chest and axillary region, with D. albipictus often being found on the back 18 . A survey of dogs and cats across the US identified a similar distribution of ticks on dogs, with the attachment being most common on the abdomen, axillary and inguinal regions.…”

Determining the preferred attachment site of tick species endemic to New York State and the influence of pathogen infection on body-segment selection in the deer tick, Ixodes scapularis

“…The attachment site of ticks has been studied in the context of both animal and human tick preference. In Oklahoma, a study of horses indicated that A. americanum preferentially bites the inguinal area while I. scapularis and D. albipictus, the moose-tick, primarily bite the chest and axillary region with D. albipictus additionally often being found on the back [31]. A survey of dogs and cats across the US identi ed a similar distribution of ticks on dogs, with the attachment being most common on the abdomen, axillary and inguinal regions.…”