THE EFFECT OF UTILIZING FORAGE PEA FOR HAY ON FEED INTAKE, RUMINAL FERMENTATION, AND DIGESTIBILITY WHEN FED TO BEEF CATTLE
Date
2020-01-06
Authors
Journal Title
Journal ISSN
Volume Title
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ORCID
0000-0001-9992-223X
Type
Thesis
Degree Level
Masters
Abstract
The purpose of this research was to evaluate field pea (Pisum sativum L.; c.v. CDC Horizon) harvested as hay on feed intake, ruminal fermentation, and total tract digestibility in beef heifers. In the first study, pea hay was mixed with barley (CDC Maverick) or oat (CDC Haymaker) hay at 0, 15, or 30% of the hay dry matter (DM), and offered ad libitum to ruminally-cannulated Hereford crossbred heifers in a 6 × 6 Latin square design. In the second study, field pea hay (CDC Horizon) was harvested at early, mid, or late stages of maturity. Pea hay was included at 40% of the dietary DM, and the diet was offered ad libitum to ruminally-cannulated Speckle Park heifers in a duplicate 3 × 3 Latin square design. In Study 1, dry matter intake increased with pea hay inclusion rate relative to 0% inclusion (P = 0.03). Ruminal fermentation was altered as mean ruminal pH increased with pea inclusion relative to 0% inclusion (P ≤ 0.013). There was no difference in total short-chain fatty acid (SCFA) concentration (P ≥ 0.55) while pea hay inclusion rate linearly increased butyrate and decreased propionate (P ≤ 0.013); furthermore, ruminal ammonia increased quadratically with inclusion rate (P < 0.001). Pea hay inclusion rate did not affect microbial protein synthesis or nitrogen retention (P ≥ 0.77). In Study 2, advancing maturity of pea hay resulted in numerically greater forage DM yield, but did not affect dry matter intake, ruminal SCFA concentration, or total tract digestibility. Advancing maturity decreased rumination (P ≤ 0.016), ruminal pH (P = 0.005), and ruminal passage rate (P = 0.022). The data from these two studies suggest that CDC Horizon field pea is a potential forage source for beef cattle that may increase CP content of the forage and increase dry matter intake without compromising ruminal fermentation. When field pea is grown in combination with cereal forage, the whole-crop pea may be harvested based upon the maturity of the cereal hay without concern of reduced feed intake or digestibility given that pea hay maturity had only minimal effects on cattle responses.
Description
Keywords
barley hay, oat hay, pea hay, beef cattle
Citation
Degree
Master of Science (M.Sc.)
Department
Animal and Poultry Science
Program
Animal Science