Knowledge and perception of equine ticks and tick-borne diseases of Pennsylvania horse owners and caretakers.

There is limited data on current knowledge of Pennsylvania horse caretakers on tick-borne diseases (TBDs), tick identification, and tick management practices. This study aimed to determine tick knowledge, concern, and management among Pennsylvania equine caretakers using an online survey. Descriptive statistics and one-way ANOVA tests were used to analyze data. The survey received 894 responses (539 completed) from Pennsylvania equine owners and caretakers. The largest proportion of respondents cared for 3-5 horses (31 %), followed by 2 horses (27 %). Veterinarian-confirmed diagnosis rates of two TBDs, Lyme disease and anaplasmosis, were 38 % and 22 %, respectively. Most respondents (39 %) were moderately confident in recognizing Lyme disease, while most (44 %) were not confident at all in recognizing anaplasmosis. Most respondents (69 %) were either extremely or very concerned about their horses contracting any TBDs. Tick bite and TBD prevention methods used by equine caretakers included performing tick checks, using on-animal repellents, and conducting pasture/landscape management. Ten knowledge-based questions were asked, and the mean correct score was 3.97 ± 2.18 out of 10 possible points. There were significant positive associations between higher knowledge scores and previous veterinarian-confirmed equine Lyme disease diagnosis, higher concern level of TBDs, and higher frequency of tick checks. With increased equine TBD prevalence and high levels of horse owner concern about TBD, Extension educators should focus on teaching about TBDs and managing ticks on horses and farms.

Response of the hypothalamic-pituitary-adrenal axis to stimulation tests before and after exercise training in old and young Standardbred mares.

This study tested the hypotheses that age-induced alteration in cortisol, ACTH, and glucose concentrations are due to differences in the response of the hypothalamic-pituitary-adrenal axis and that exercise training would attenuate these differences. Six old (22.0±0.7 yr; mean±SE) and 6 young (7.3±0.6 yr) unfit Standardbred mares ran 3 graded exercise tests (GXT): before (GXT1), after 8 wk of training (GXT2), and at study end at 15 wk (GXT3). Mares trained 3 d/wk at 60% maximum heart rate. Each mare underwent 5 endocrine stimulation tests pre- and posttraining: 1) control (CON), 2) adrenocorticotropin hormone (ACTHtest), 3) combined dexamethasone suppression/ACTH (DEX/ACTH), 4) dexamethasone suppression (DEX), and 5) combined DEX/corticotropin releasing factor (DEX/CRF). For CON, there was no difference in plasma cortisol between age groups pretraining (P=0.19), but young mares had a 102% higher mean (P=0.02) plasma cortisol concentration than old mares posttraining. The pretraining ACTHtest showed young mares had a 72% higher (P=0.05) overall plasma cortisol concentration compared to old. There was no overall age difference in cortisol in the posttraining ACTHtest, but old mares still had lower cortisol concentrations at 30 min during the test, suggesting decreased adrenal response to ACTH stimulation. There was no difference in cortisol response between old and young mares in DEX, DEX/ACTH, or DEX/CRF tests. Young mares had higher (P=0.02) overall plasma cortisol concentration posttraining in response to DEX/ACTH, but old mares showed no change. In CON and DEX/CRF, there were no age differences in plasma ACTH concentration, pre- or posttraining. Pretraining, there was no age difference in glucose response to DEX, but posttraining old mares had a 4% (P=0.04) lower overall plasma glucose concentration compared to young. Posttraining, old mares had lower mean plasma glucose concentrations during DEX compared to pretraining (P=0.02), but there was no change pre- vs. posttraining in young mares (P=0.19). Old and young mares had lower plasma glucose concentrations posttraining during DEX/ACTH (P<0.001 and P=0.05, respectively) and DEX/CRF (P<0.001 and P=0.003, respectively) compared to pretraining. Both the pituitary and adrenal glands experience a decline in function with age although the exact mechanisms behind such changes remain unknown. Exercise training facilitates the counteraction of these deficits.

Oxidative stress and antioxidant status in intensely exercising horses administered nutraceutical extracts.

REASONS FOR PERFORMING STUDY: Many nutraceuticals are used as equine supplements without their efficacy having been scientifically tested. Black tea, cranberries, orange peel and ginger are a few of those nutraceuticals that warrant further study. OBJECTIVE: To test the effects of single doses of black tea, cranberry, orange peel and ginger extract on markers of oxidative stress and antioxidant status following exercise in horses. METHODS: In Study 1, 9 mature, healthy but unfit Standardbred mares were administered 2 l of a control (water), orange peel extract (30 g extract) or decaffeinated black tea extract (28 g extract). In Study 2 the same mares were administered 2 l of a control (water), cranberry extract (30 g extract) or ginger extract (30 g extract). In each study, mares were given the extracts via nasogastric tube 1 h before performing a graded exercise test (GXT), in a randomised crossover design with at least 7 days between GXTs. Blood samples were collected at rest, at fatigue, and 1 and 24 h post exercise and analysed for lipid hydroperoxides (LPO), total glutathione (GSH-T), glutathione peroxidase (GPx), α-tocopherol (TOC), ß-carotene (BC) and retinol. Data were statistically analysed using a repeated measures ANOVA. RESULTS: In Study 1 there was no effect of treatment for LPO, GSH-T, GPx, TOC or BC. Retinol was higher for both tea (P = 0.0006) and water (P = 0.004) than for orange peel. In Study 2 there was no treatment effect for LPO, GPx, GSH-T, RET, BC or TOC. CONCLUSIONS: The results show that a single dose of various nutraceuticals in exercising horses do not produce an effect on either oxidative stress or antioxidant status and further investigation is needed as to whether long-term supplementation would enhance these effects.