| dc.description.abstract | The United States Cattle Fever Tick Eradocation Program serves to prevent the reestablishment of cattle fever ticks (Rhipicephalus (Boophilus) spp.), and the risk of Texas cattle fever from Mexico. The primary detection method for fever ticks on cattle is through the manual palpation of restrained animals in an attempt to feel for attached ticks. This method involves using bare hands to feel through the hair coat of the host animal for attached ticks, but due to their small size only adults and engorged nymphs are usually discovered in this way. The threshold tick population for detection by human inspection affected by many variables from weather related influences to risks inherent with physical examination of restrained cattle. New methods for detecting animals infested with cattle fever ticks are needed to improve the reliability of human inspection. Ticks mediate host immune responses for successful blood feeding. Interactions of host immune, endocrine and digestive systems impact digestion and resulting fecal chemistry. These studies were conducted to determine whether near-infrared reflectance spectroscopy could detect differences in fecal samples from infested and non-infested cattle, to determine the effects of fecal ageing and environmental exposure on NIR spectra, and to compare the abilities of a bench-top and portable spectrometer for NIR assessment of bovine feces from tick infested cattle. Fecal samples were taken daily from 6 Bos taurus cattle infested with R. microplus and 6 non-infested Bos taurus cattle fed on a standardized pelleted diet for 60 days. Fecals were ground, dried and subjected to NIRS scans by a FOSS 6500 spectrometer, and the resulting spectra were analyzed using GRAMS IQ. Analysis revealed fecal chemistry changes consistent with the on-host phase of the life cycle of Rhipicephalus (Boophilus) microplus. Cluster analysis indicates exposure of fecal pats for 12-days in open and shaded habitats during cool and warm weather periods did not change NIR spectra. NIR spectra from fecal samples can be collected and analyzed by low-cost portable systems and these systems offer the ability to conduct analyses in the field and on demand. | |
