AbstractsBiology & Animal Science

Maximizing Equine Forage Utilization through the Reduction of Hay Waste and Grazing Alternative Pasture Species

by Amanda Grev




Institution: University of Minnesota
Department:
Year: 2015
Keywords: Annual grasses; Forage nutritive value; Hay intake; Hay waste; Horse preference; Small square bale feeder
Posted: 02/05/2017
Record ID: 2063560
Full text PDF: http://hdl.handle.net/11299/174769


Abstract

Hay waste during feeding represents a costly expense for horse owners. The objectives of this study were to determine hay waste, herd bodyweight (BW) change, hay intake, and economics of small square-bale feeders used in outdoor feeding of adult horses. Feeder designs included a hayrack, slat feeder, basket feeder, and a no-feeder control. Feeders were placed in separate outdoor dirt paddocks. Twelve adult horses were divided into four groups and rotated through the paddocks in a Latin square design. Horses were weighed immediately before and after each rotation. Horses were fed grass hay at 2.5% of the herd BW split evenly at 0800 and 1600 hours. Waste hay and orts were collected daily before each feeding. The number of months to repay the feeder cost (payback) was calculated using hay valued at $250/ton, and improved efficiency over the no-feeder control. Mean hay waste was 13, 5, 3, and 1%, for the no-feeder control, hayrack, basket feeder, and slat feeder, respectively. The hayrack, basket feeder, and slat feeder paid for themselves in 12, 11, and 9 months, respectively. Herds gained 10 and 7 kg when feeding from the basket feeder and hayrack, and lost 3 and 11 kg when feeding from the slat feeder and no-feeder control (P ≤ 0.0015). Estimated hay intake was 2.4% BW for the basket feeder and hayrack and 2.2% BW for the slat feeder and no-feeder control (P < 0.0001). Small square-bale feeder design affected hay waste, hay intake, herd BW change, and payback. Annual grasses can serve as emergency forage but have not been evaluated under horse grazing. The objectives of this study were to evaluate annual grasses for yield, forage nutritive value, and preference under horse (Equus caballus L.) grazing at two maturities during the spring and fall. Spring grasses were planted on May 8, 2013 and April 22, 2014 in a randomized complete block (RCB) with eight replicates. Fall grasses were planted on August 1, 2013 and August 5, 2014 in a RCB with six replicates. Beginning in June and September of each year, adult horses grazed half of the replicates for four hours at an immature stage. Approximately one week later, horses grazed the remaining plots at a mature stage. Plots were mowed and grazing was repeated when annual grasses regrew to the target maturities. Although spring and forage oat (Avena sativa L.) and winter barley (Hordeum vulgare L.) often had the highest yields (≥ 3.9 t ha-1; P ≤ 0.0455) across seasons and maturities, they were among the least preferred annual grasses (≤ 28%; P ≤ 0.0498). Across seasons and maturities, annual ryegrass (Lolium multiflorum L.) and winter and spring wheat (Tricum aestivum L.) were the most preferred annual grasses with ≥ 45% removal (P ≤ 0.0370). Among these highly preferred grasses, annual ryegrass was typically higher yielding (≥ 4.7 t ha-1), while winter and spring wheat were among the lowest yielding species (≤ 6.4 t ha-1; P ≤ 0.0455). Although differences were observed, all annual grasses resulted in ≥ 15% crude protein (CP), ≤ 59% neutral detergent…