Dry Matter Intake, Body Weight, and Body Condition Scores of Blanketed and Nonblanketed Horses in the Upper Midwest

What the hay: predicting equine voluntary forage intake using a meta-analysis approach

To properly formulate diets, the ability to accurately estimate feed intake is critical as the amount of feed consumed will influence the amount of nutrients delivered to the animal. Inaccurate intake estimates may lead to under- or over-feeding of nutrients to the animal. Individual differences in equine forage intake are well-known, but predictive equations based on animal and nutritional factors are not comprehensive. The objective of the present study was to consolidate the current body of knowledge in the published literature on voluntary forage DM intake (VFDMI) in equines and conduct a meta-analysis to identify driving factors, sources of heterogeneity, and develop predictive equations. Therefore, a systematic literature search was applied and identified 61 publications which met the inclusion criteria. From each study, the outcomes of interest (e.g., forage intake), diet composition (e.g., forage information, nutrient composition), and animal factors (e.g., sex, age, breed, BW, exercise level) were extracted. Forage intake was analyzed as two different outcome variables: (1) VFDMI in kg/d and (2) VFDMI in g/kg BW. Linear mixed model analysis treating study as a random effect was applied, using a backward-stepping approach to identifying potential driving variables for VFDMI (both units) where all terms have P < 0.1. The best fitting models for VFDMI included similar factors (also across kg/d and g/kg BW) such as forage quality (i.e., neutral detergent fiber or CP content), forage type (i.e., grass, legume, or mixed), the animals' size category (i.e., horses vs ponies), and some management factors (i.e., pasture access). As anticipated, forage intake increased when higher quality forages were fed (i.e., lower neutral detergent fiber or higher CP), potentially due to improved digestibility. Additionally, VFDMI increased as BW increased but ponies increased their VFDMI more per every kg increase in BW compared to horses. Lastly, pasture access (i.e., grazing) may influence VFDMI such that pastured animals consume less than stalled animals, possibly due to the time it takes to graze forage. In conclusion, equations to predict equine VFDMI with high accuracy and precision (concordance correlation coefficient  = 0.82 - 0.95; root mean squared error RMSE = 0.82-5.49) were developed which could be applied in practice by equine nutritionists or owners and managers. The results of this meta-analysis confirm that animal traits and forage quality have a significant impact on the VFDMI of equines and should be accounted for when formulating diets to ensure nutritional requirements are met.

Changes in Hair Coat Length and Diameter in Blanketed and Nonblanketed Adult Horses in the Winter

Horses are often blanketed during cold weather for numerous reasons including assisting thermoregulation, cleanliness, and anecdotally to decrease hair coat length. However, the impact of blanketing on the hair coat has yet to be evaluated. The objective of this study was to evaluate changes in hair coat length and diameter over time in blanketed and nonblanketed horses during winter. In October 2019, 16 mature adult horses were blocked by breed and BCS and randomly assigned to a blanketed (n = 8) or nonblanketed (n = 8) treatment; blankets were placed. Data was collected between October 2019 and March 2020 in River Falls, WI. During this time BW, BCS, and hair coat samples were taken monthly. Twenty hair coat samples were taken from the nonmane side of the neck and the hindquarters using a tweezers and measured for the length and diameter using a digital micrometer and caliper, respectively. The average measurement was used to analyze the data. Horse neck and hindquarter hair were the longest and had the greatest diameter in January and February and they were the shortest with the smallest diameter in October and March regardless of treatment (P ≤ .05). Blanketed horses had shorter neck hair length when compared to nonblanketed horses in January at 43 and 58 mm, respectively, and February at 35 and 47 mm, respectively (P ≤ .05). These results suggest blanketing a horse can alter hair coat length, however, hair coat growth over time follows a similar pattern regardless of blanketing practices.

Winter blanketing practices: An online survey of North American horse owners

Blanketing is a highly debated practice utilized in the equine community as part of winter horse management. Despite this, little research is available on the prevalence, reasoning, and management decisions related to use of blankets for horses in North America. Therefore, the objective of this study was to develop an understanding of blanketing management practices and beliefs of North American horse owners. A 33-question, branched online survey was developed and available between December 1, 2020 and January 5, 2021 and advertised using social media and e-newsletters. The FREQ procedure for Chi-squared analysis in SAS was used when comparisons were made between participant-reported frequencies. There were 1,450 respondents from North America who completed the survey. Demographic information indicated the majority of respondents were from the Midwest region of the United States (68%); however, geographical region did not impact the frequency of blanket usage (P = 0.17, X² = 8.99). When respondents were asked to self-report discipline, recreational riding was the most prevalent (40%). Overall, 54% of respondents (n = 790) reported blanketing the majority of their horses during the winter. The most frequently selected reason respondents chose to blanket horses was exposure to precipitation (78%). Out of the respondents who did not blanket the majority of their horses (n = 660), the primary reason for not blanketing was access to shelter (50%). This survey provides valuable information on blanketing and winter management practices reported by horse caretakers in North America and will help direct future research and education efforts.