Graduate Thesis Or Dissertation
 

Prevalence of Deficiency and Relationship of Management Practices to Vitamin E and Selenium Status in Horses

Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/j3860d03q

Descriptions

Attribute NameValues
Creator
Abstract
  • Deficiency of selenium (Se) or alpha-tocopherol (E) creates serious health issues in horses. This study evaluated owner supplementation practices and their efficacy at preventing deficiency in a large population of horses. In addition, common clinical signs of horses presenting to a referral institution who had Se and E testing performed was also investigated. Whole blood (Se) and plasma (E and beta-carotene) samples were collected from 331 adult horses. A comprehensive questionnaire determined source and estimated content of Se and E in each horse’s daily ration, ration composition, pasture access and exercise demand. Data were analyzed via ANOVA, Spearman’s correlation coefficient and contingency tables (P < 0.05). Medical records of 216 equine cases presenting to the OSU VTH between 2005 and 2019 were obtained and case details, presenting signs and final diagnosis were reviewed. Supplemental Se was provided to 87.6% of horses of which 71.3% received ≥ 1 mg/day. Deficient blood [Se] (<80 ng/ml) was documented in 3.3% of horses, and 13.6% were marginal (80-159 ng/ml). Non-supplemented horses were twenty times more likely to be deficient than horses receiving Se. Exercise, provision of Secontaining salt, or form of Se (inorganic vs. organic) did not significantly influence blood Se concentration. Supplemental E was provided to 87.3% of horses; 57.7% received ≥ 500 IU/day, more frequently as the synthetic form (60.7% of horses). Deficient (< 1.5 ug/ml) and marginal (1.5-2.0 ug/ml) plasma [E] occurred in 15.4% and 19.9% of sampled horses, respectively. Pasture access (≥ 6 hours/day) was significantly protective against low plasma [E], as was daily provision of ≥ 500 IU of alpha-tocopherol. Exercise and supplement form (synthetic vs. natural) did not clearly influence plasma [E]. Pasture access correlated significantly with plasma betacarotene concentrations (0.19 ± 0.33 ug/ml), which currently have limited documentation in horses. Of equine cases presenting to the OSU VTH, deficient blood [Se] was documented in 14.4% and 22.3% were marginal. Most commonly reported clinical signs for horses with documented Se deficiency included muscle or weight loss (59.3%) and rhabdomyolysis (30%). Deficient and marginal serum [E] occurred in 24.4% and 12.5% of sampled horses, respectively. Most commonly reported clinical signs for horses with documented E deficiency included muscle or weight loss (48.8%) and weakness (32.6%). Although most owners provided supplementation, over 40% of horses were not meeting nutritional minimums for daily Se and E. Deficiency of Se was likely in horses located in areas with low soil Se and without appropriate directed supplementation, which increased risk of deficiency by twenty times. Selenium salt blocks, although commonly provided, were not protective. Restricted pasture access increased E deficiency risk two times. Dual deficiency of E and Se was common in this population and clinical signs were not predictive of deficiency, highlighting the need for blood testing.
License
Resource Type
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Rights Statement
Publisher
Peer Reviewed
Language
Embargo reason
  • Ongoing Research
Embargo date range
  • 2019-06-14 to 2021-07-14

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
file details PitelMariyaO2019.pdf 2019-06-13 Public Download