HABITAT SELECTION BY EXOTIC DAMA GAZELLES (NANGER DAMA RUFICOLLIS) IN TEXAS

Habitat selection information is important for both breeding on Texas ranches and repatriation in Africa. This is especially true for the critically endangered dama gazelle (Nanger dama). Exotic dama gazelles of the eastern subspecies (N. dama ruficollis) wearing GPS-radio collars were tracked for one year on two Texas ranches. Three adult and two subadult males were collared from a large (8,996 ha) pasture in west Texas. Next, collars went on all males plus all females released into a 202 ha Edwards Plateau pasture (seven adult females, one maturing male, and one to three adult males). On both sites, the gazelles favored the less steep terrain of the Ector soil series. Adult male core areas averaged 440 ha in west Texas (vegetation sparse) and 57 ha on the Edwards Plateau (dense food stands). These relationships allowed for estimation of the number of adult males that could be stocked in the larger pasture while still allowing room for the males to spread out. No special affinity for water sources was found, although dama gazelles do drink during hot weather when water is available. There was no consistent seasonal distributional change noted. On both Texas sites, the gazelles survive on natural browse. Where there are feeders, competition from larger animals kept gazelles out. For breeding or restoring populations, flat-to-gently rolling terrain with ample browse is best. Shade and water are important, and any supplemental feed requires access. There also needs to be enough favored habitat to accommodate the adult males without dangerous conflict.

Helminth fauna in a semi-arid host species – scaled quail (Callipepla squamata)

Helminths were examined from 145 scaled quail (Callipepla squamata) collected during the 2012–2013, 2013–2014 and 2014–2015 hunting seasons from a semi-arid region of Texas that spans four ecoregions. Helminth infracommunities were species poor, averaging 1.7 (range 1–4) species. Six species occurred within the component community of which one (Oxyspirura petrowi) is known to be pathogenic to quail. Aulonocephalus pennula was most abundant (9991 individuals, 95% of total) followed by O. petrowi (391 individuals, 4%). Each of the remaining four species was rare (≤21% prevalence) and contributed few individuals (<1%). In the High Plains ecoregion, prevalence of O. petrowi was higher in host collections made during the 2013–2014 hunting season than either hunting seasons 2012–2013 or 2014–2015 and was higher in the High Plains ecoregion than the Edwards Plateau ecoregion during the 2013–2014 hunting season. Mean abundance of A. pennula and O. petrowi was higher in scaled quail from the High Plains ecoregion than the Edwards Plateau ecoregion. Our results provide new information about helminth fauna in scaled quail, persistence of indirect lifecycle helminth species within a semi-arid region, and the occurrence of pathogenic helminth species within this host species.

125 Tick burden observed on cattle and sheep during winter season on the Edwards Plateau of Texas

Multi-species livestock grazing is a common practice in the Edwards Plateau of Texas. Winter demands on livestock are high because of forage quality and quantity limitations and stresses of tick parasitism. Our objective was to assess winter-active tick burden on livestock and gauge effectiveness of a pour-on synthetic pyrethroid acaricide. At the Sonora AgriLife Station, 26 Bos taurus crossbred heifers (260 ± 6 kg) and 28 Dorper ewes (42 ± 1 kg) were maintained on 97.125 hectares of rangeland. Tick burden was assessed by individual animal inspection on: 12-18-2017, 01-05-2018, 01-122018, 01-26-2018, 02-09-2018, 02-16-2018, 02-23-2018, and 03-08-2018. Trial 1 acaricide treatment was applied 01-05-2018 on heifers and ewes chosen randomly to serve in the non-treated control (13 heifers; 14 ewes) or acaricide-treated (13 heifers; 14 ewes) groups. Trial 2 acaricide treatment was applied 02-16-2018 using a switchback design. Tick species included Amblyomma americanum, Dermacentor albipictus, and Ixodes scapularis. Tick burden differences were determined by analysis of variance procedures. There were no differences in tick burden on heifers or ewes prior to acaricide application for Trial 1 nor Trial 2 (P > 0.276, 0.002 ± 0.46; P > 0.354, 0.002 ± 0.11 and P > 0.606, 0.002 ± 0.05; P > 0.705, 0.001 ± 1.34, respectively). There were no differences (P > 0.149) between acaricide-treated (0.519 ± 0.05) and non-treated control (0.644 ± 0.07) heifers in Trial 1 nor Trial 2 (0.759 ± 0.07 and 0.404 ± 0.04, respectively). Similarly, there were no differences (P > 0.997) between acaricide-treated (2.964 ± 0.31) and non-treated control (2.965 ± 0.3) ewes in Trial 1 nor Trial 2 (1.015 ± 0.13 and 5.563 ± 0.45, respectively). We conclude ticks challenge the well-being and production in overwintering livestock in the Edwards Plateau. Alternative acaricides should be evaluated for efficacy and efficiency in these production systems