Submitted to: Journal of Medical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/2/1998
Publication Date: N/A
Interpretive Summary: The success of the cattle fever tick eradication program is due in part to the high degree of host-specificity of Boophilus spp. which are primarily ectoparasites of cattle. However, ticks are occasionally found on other species. Thus, determination of the suitability of potential alternative hosts is critical to the eradication program. Since goats are found abundantly in the quarantine zone along the Texas-Mexico border, a study was initiated to determine the potential of goats as an alternative host of B. annulatus. The host suitability of restrained and unrestrained goats infested with cattle fever ticks was compared with that of cattle. When ticks were infested on restrained goats and cattle, it was found that there was no difference in the number of ticks recovered from the goats as compared to the cattle. However, when infested goats were allowed to remain unrestrained during the tick parasitic cycle, no adult female ticks were recovered from the goats. These results indicated that goats were both efficient and aggressive in grooming themselves and preventing ticks from reaching repletion. It was concluded that goats were poor hosts of fever ticks based on the lack of engorgement success on unrestrained hosts, which is more representative of natural conditions.
Technical Abstract: Spanish short-haired goats (Capra hircus)and cattle (Bos taurus) were infested with Boophilus annulatus (Say) larvae for determination of host suitability under restrained and unrestrained conditions. No adult female ticks were collected from unrestrained goats. Female tick recovery rate on unrestrained calves was 26.0%. There was no significant difference in the number of female ticks collected from restrained goats (22.0%) and restrained calves (24.6%). These observations indicate that grooming behavior of goats greatly inhibited the engorgement success of these ticks. The parameters of engorged female weight, preovipositional period, egg mass weight, incubation period, conversion efficacy, and per cent egg hatch were compared for ticks reared on each host species under restrained conditions. No significant differences were observed for the means of any of these parameters. Although B. annulatus completed engorgement on restrained goats, it was concluded that these animals were poor hosts based on the lack of engorgement success of these ticks on unrestrained hosts, which is more representative of natural conditions.