Please read the abstract in the section 00front of this document / Dissertation (MSc Agric (Microbiology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted

Unwanted horses are a growing problem in the United States, and through the use of surveys, researchers can understand public opinion and experiences related to this problem. This study administered surveys specific to horse and non-horse owners through face-toace delivery and to rescue/retirement and auction facilities through the mail. Data was analyzed using a CRD, GLM and Fisher’s Protected LSD with á of 0.05. Comparisons were completed between horse and non-horse owners, horse owners and non-horse owners with equine experience, non-horse owners with and without equine experience, Quarter horse and other breeds owners, and auction and rescue/retirement facilities. Similarities were seen between groups for questions associated with participant location, understanding of processing/harvesting regulations and procedures, processing/harvesting facility restrictions preferences, and knowledge of management cutbacks and rescue facility locations. The only question that was significantly different for all comparisons was concerning the support towards the reopening of equine processing/harvesting facilities.

Autism is a disorder that has increased in numbers and prevalence within today’s society. Though no cure has been found, recent studies have focused on different therapeutic intervention techniques offered to autistic individuals, including the use of Therapeutic Horseback Riding. This study analyzes the relationship of therapeutic horseback riding on gross motor function in children with Autism. Four children participated in a ten week previously established therapeutic horseback riding program at French Camp, Mississippi. Gross motor function was assessed before and after five riding sessions by recording performances of eleven skills from Motor Skills Inventory (MSI). Only two participants completed all riding sessions and MSI assessments to be eligible for this study. Statistical analysis was conducted using Friedman’s Two Way Analysis of Variance by Ranks. There were no significant differences in the assessments before/after the riding sessions as well as the entire period of the ten week program.

Six mares and six geldings were used to determine the effect of forage quality on muscle glycogen utilization by exercised horses. Horses were fed 1.5% BW/d of high quality (65.6% NDF; 41.1% ADF) or low quality (74.6% NDF; 51.2% ADF) hay and a concentrate resulting in three diets: high quality hay and concentrate balanced to meet energy requirements (HQ); low quality hay and concentrate balanced to meet energy requirements; and low quality hay with the same amount of concentrate as the HQ diet. The effect of hay quality on serum insulin, serum glucose, whole blood lactate, and respiratory parameters were also determined. Results suggested varied metabolic responses to exercise between sexes and a possible glycogen sparing effect when low quality forage was consumed.

The use of electrolytes in horses has become common in the equine community. Proper management of the equine athlete encourages the supplementation of electrolytes, especially during exercise. Electrolyte imbalance can cause physiological issues including fatigue, irregular heartbeat, cramping, and more. Electrolyte supplementation is utilized to replace losses via the sweat, urine, and defecation. Commercially available oral electrolyte forms include paste, powder, and pellets. Work describing chewable electrolyte use in horses has not been published. The objective of this work is two-fold: to determine preference across four electrolyte chew flavors and to ascertain efficacy of a novel electrolyte product. Protocol approval (#21-029) by Southern Illinois University Institutional Animal Care and Use Committee was obtained prior to initiation of this work. The study was completed in two phases. The first phase examined the palatability of the novel electrolyte chew while the second phase tested the serological effect of the product in exercising horses. In the first phase, stock-type horses (n = 10) were utilized for individual preference testing in palatability stocks over six days. During the palatability session, each horse was permitted 30 seconds to olfactorily investigate the product prior to release for consumption. Immediately following the olfactory period, each horse was allowed up to 5 minutes to voluntarily consume the electrolyte chews. Horses were presented with four treatments (A, B, C, D) on an alternating basis, with two treatments offered side-by-side per day. Treatment formulations consisted of the same base electrolyte content with varying flavors of peppermint, salt, and orchard grass (Table 2). Treatment locations were switched daily to prevent bias associated with location. Variables of interest included number of chews consumed (TI), first action (FA), first choice (FC), time spent consuming (TC) and water consumption (WC) were recorded. Bodyweight (BW) and body condition scores (BCS) were recorded twice over the study duration. Data were analyzed via numerical and categorical methods using PROC GENMOD, PROC FREQ & PROC GLM of SAS (v. 9.5). Significance was set at P < 0.05. There was no significant overall preference for any of the treatment formulations examined. However, there was a significant difference in chew consumption between days 1 and 2 (P = 0.0204). There was also a highly significant treatment effect between days 5 and 6 (P < 0.0001). The relationship between individual horse and consumption was variable and highly significant (P < 0.0001). The mean acceptance rate of the product was 63.6%. These results indicate palatability may differ significantly across horses for the flavors examined. In the second study phase, privately-owned local foxhunting horses (n = 15) were utilized in an exercise study. Due to poor consumption, nine horses were selected for use in the experiment to test treatments. There were three treatment groups: control (CON) offered no supplementation, light (LIG) consumed 6-9 chews, and moderate (MOD) voluntarily consumed 15-20 chews. Baseline jugular venipuncture and vitals assessments were completed on all horses prior to supplementation. Supplementation was offered in two parts: 30 minutes pre-ride and immediately following a 2-hour foxhunt ride in the afternoon. Afternoon temperature was 52°F with mostly sunshine and approximately 42% humidity. Upon return, horses were immediately offered electrolyte supplementation. Venipuncture and vitals assessments were repeated 30 minutes post-ride. Variables recorded were serum values (Na, K, Cl, Ca, HCO−3, Mg), chew consumption (TI), age, respiratory rate (RR), skin turgor (SKN), rectal temperature (BT), distance travelled (DIS) and average speed (SPD). Categorical variables were body condition score (BCS), sex, breed (BRD), and sweat rating (SWR). Data was analyzed via PROC GLM, PROC FREQ and PROC REG dependent on test with SAS (v. 9.5). Significance for all tests was set at P < 0.05. Serological values were unaffected by electrolyte consumption (P > 0.05). Body temperature was significantly higher for all horses following exercise, regardless of treatment group (P = 0.0005). Skin turgor showed significantly more time before return to original state during post-ride evaluation (P = 0.0013). Directional serum changes between Cl and K were significantly correlated (P = 0.0227) as well as Mg and Cl (P = 0.0316). Correlations of relational change between Ca and HCO−3 in addition to Ca and Na were approaching significance (P = 0.0707; P = 0.0800). Mares demonstrated a greater ability to maintain lower post-ride serum calcium levels than geldings (P = 0.013). The effect of breed on serological calcium change may also be considered (P = 0.0312). These results suggest that several major contributive factors require further investigation for the successful implementation of oral electrolyte chews into equine exercise regimens.

The purpose was to objectively measure the rate of healing of equine distal limb wounds when a 10% Natural Proprietary Compound (NPC) was compared to a topical antibacterial cream (1% silver sulfadiazine- SSD). Five horses had two wounds measuring 6.25cm2 created on the dorsomedial aspect of each limb. Two contralateral limbs were randomly chosen to be bandaged and the other two limbs were un-bandaged – with one limb of each group being treated with either NPC or SSD. On each limb the most proximal wound was left without topical treatment to act as a control. There was no significant difference between SSD and the compound evaluated in this study when either perimeter or area was assessed. Control wounds were significantly smaller than those treated with an ointment regardless of other variables, giving rise to a proposed location effect. Bandaging by day was significant for the time period approximating 2-5 weeks.

No description available.

The aim of this study was to evaluate the use of a hyperimmunized plasma containing high concentration of antibodies against Clostridium difficile, Clostridium perfringens and Salmonella sp in a referral population of equine colitis cases. A prospective, blinded clinical trial was undertaken. Horses were enrolled if they were over 1 year old, duration of diarrhea at presentation was less than 72 hours, they had not received equine plasma within the last 3 months and the serum total protein was greater than 4mg/dl. Horses were randomized to receive hyperimmunized plasma, control plasma (collected from non-immunized horses) or no plasma therapy. Clinical parameters were recorded and a fecal score (2 -14) assigned (every 6 hours) based upon diarrhea frequency, volume and consistency, for a total of 72 hours. A score less than 5 was considered normal. Fecal consistency was observed until resolution, discharge or death. Complete blood counts and biochemical profiles were collected at admission, 24 and 72 hours and at admission, 24 hours and 48 hours respectively. Forty two horses were enrolled and 38 horses completed the study. At study admission clinical and clinicopathological parameters, other than fecal frequency score were comparable between the groups. Fecal frequency score was significantly different between the treatment groups (p=0.003). The mean duration of diarrhea was 40.7±9.8 hours (mean ±SEM), 119.2±56.1 hours and 72.0±24.5 hours for the hyperimmunized plasma, normal plasma and control groups respectively. This data confirms the hyperimmunized plasma used in this study decreased the time to resolution of diarrhea. / Master of Science

Fecal recoveries of n-alkanes were determined in three digestion balance experiments consisting of two periods each. Each experiment compared two diets in a switch-back design using eight mature Thoroughbred geldings. Horses were randomly assigned to two groups of four and offered one of two mixed grass/legume hays (Diets 1 and 2) in Exp. 1, mixed grass/legume hay and one of two concentrates (Diets 3 and 4) in Exp. 2, and mixed grass/legume pasture (Diets 5 and 6) in Exp. 3. In Exp. 1 and 2, horses were housed in stalls and in Exp. 3, two horses from each diet were housed in stalls and two horses remained on pasture. Balance periods lasted 11 days with d 1 to d 7 consisting of a dietary accommodation period, followed by 4 days of total collection. Results indicated that fecal recoveries of odd-chain alkanes (C25 to C33) were less than 100 % and similar between chain lengths. Estimates of DMD (DE) were similar to the total collection DMD (DTC) for Diet 1 in Exp. 1, but underestimated DTC for Diet 2 in Exp. 1 (P < .05) and Diets 3 and 4 in Exp. 2 (P < .05). For Diet 5 in Exp. 3, the DE for stall-fed horses using C25 and C33 was similar to DTC, whereas C27, C29, and C31 underestimated DTC (P < .05). For pastured horses, the DE using C29 and C31 were similar to DTC, whereas C25, C27, and C33 underestimated DTC (P < .05). For Diet 6 in Exp. 3, the DE for stalled horses calculated using C25 was similar to the DTC, whereas use of C27, C29, C31, and C33 underestimated DTC (P < .05). For pastured horses, the DE using C29 was similar to DTC, whereas all other alkanes underestimated DTC (P < .05). When DE was adjusted (DA1) using the mean recovery of each odd-chain alkane, DA1 was similar to DTC for Diet 2 in Exp. 1, Diets 3 and 4 in Exp. 2, and stalled horses offered Diets 5 and 6 in Exp. 3. The DA1 using C25 underestimated DTC for Diet 1 in Exp. 1 (P < .05). For pastured horses offered Diet 5, DA1 for C33 was not different from the DTC estimate, whereas all other DA1 for n-alkanes overestimated DTC (P < .05). For pastured horses offered Diet 6, DA1 for C29 and C31 overestimated, but were similar to the DTC, whereas the DA1 for C33 underestimated DTC and was similar to the DTC. The DA1 for C25 and C27 overestimated DTC (P < .05). When DE was adjusted for the mean recovery of all n-alkanes (DA2), all DA2 estimates for stalled horses in Exp. 1, 2, and 3 were similar. In pastured horses offered Diets 5 and 6 in Exp. 3, the DA2 overestimated DTC (P < .05). These results suggest that accurate mean estimates of DMD can be obtained by adjusting for mean recovery of each odd-chain alkane in a specific diet. / Master of Science

Lidocaine continuous-rate infusions (CRI) are the most commonly used prokinetic in equine practice for the treatment of post-operative ileus and are also increasingly being used in pain management, such as in cases of severe laminitis, and are often used for prolonged durations. To date only limited time/concentration relationships of lidocaine administered as a short term (24hours) CRI to horses are reported. This study examined the time/concentration profile of lidocaine and its active metabolites (GX, MEGX) during a 96 hour lidocaine infusion in eight mature healthy horses. Serum lidocaine concentrations reached steady state by three hours and did not accumulate thereafter. The serum concentration of lidocaine was above the target therapeutic concentration (980ng/ml) only at 6 and 48 hours. The serum lidocaine concentration did not reach the range described as potentially causing toxicity (>1850ng/ml). The MEGX metabolite did not accumulate over time, while the GX metabolite accumulated significantly up to 48 hours and then remained constant. The serum concentrations of lidocaine, MEGX and GX were below the limit of detection within 24 hours of discontinuation of the infusion. None of the horses developed any signs of lidocaine toxicity during the study. It was concluded that the metabolism of lidocaine was not significantly impaired by prolonged infusion, contrasting with studies in dogs and humans. No adverse effects were observed in this study, which with the lack of lidocaine accumulation suggests that prolonged infusions are safe. However the accumulation of GX, a potentially toxic active metabolite, is cause for concern. / Master of Science