Evaluation of the bloating potential and grazing performance of AC-Grazeland verses a mixed AC-Grazeland and Sainfoin pasture for beef cattle in southwest Saskatchewan
The potential benefits of grazing alfalfa (Medicago sativa L.) are well documented (e.g., high yields and forage quality, excellent animal gains) and thus, many livestock producers are interested in its use. However, alfalfa’s ability to cause bloating in cattle and potential death has caused many livestock producers to not consider grazing pure alfalfa stands or only alfalfa/grass mixtures in which the alfalfa constitutes less than 20% of the forage stand. The recent availability of AC-Grazeland (AC), a low bloat causing alfalfa cultivar, and the use of non-bloating legumes in mixture with alfalfa are reported grazing strategies to reduce the occurrence of bloating and may be a method to increase the ability to graze alfalfa in the pasture at higher proportions. The objective of this study was to evaluate the bloating potential or bloat reducing potential and animal grazing performance of AC verses a mixed AC and sainfoin (AC+S) pasture. In 1998, one pasture (4.9 ac) was seeded to AC, while another pasture (4.4 ac) was seeded to an AC+S mixture. Seeding rate for the AC and Sainfoin (S) were 5 and 38 lbs per acre, respectively. Grazing of the two pastures were initially started in 2000 by an equal number of yearling steers. Grazing and forage data from 2002 and 2003 were used in this study. Yearling steers commenced grazing on the AC pasture at the early bud stage and the S was grazed at the early flower stage. Each steer on the AC pasture received a rumensin CRC bolus, while steers on the AC+S received no rumensin boluses. Results found that no bloating or bloat symptoms were observed in the cattle grazing from either forage treatment in 2002 and 2003. Average daily gains and total live production did not differ (P > 0.13) between pasture treatments. Further research is needed to evaluate longevity of AC and AC+S pastures under different grazing management for southwest Saskatchewan.
Soils and Crops Workshop