July 1997

Volume 50:351-356

Grass hay as a supplement for grazing cattle I. Animal performance

Guillermo Villalobos, Don C. Adams, Terry J. Klopfenstein, James T. Nichols, and James B. Lamb
Villalobos is assistant professor, Facultad de Zootecnia, Universidad Autonoma de Chihuahua, Mexico; Adams, Nichols, and Lamb are associate professor, professor emeritus, and research associate, University of Nebraska-Lincoln, West Central Research and Extension Center, Route 4, Box 46A, North Platte, Neb. 69101; Klopfenstein is professor, Dept. of Animal Science, University of Nebraska-Lincoln, Lincoln, Neb. 68583.

Abstract

Regrowth grass hay produced on subirrigated meadows in the Nebraska Sandhills was evaluated as a supplement for gestating beef cows grazing winter range. Ninety-six crossbred spring calving, gestating beef cows were used in a winter supplementation study on upland Sandhills range from 5 November to 27 February in 1990 and again in 1991. Cows were divided into 4 treatments (24 cows/treatment): 1) control (range forage only, no supplement); 2) range forage and 2.2 kg cow-1 day-1 of meadow regrowth hay (15.5% crude protein); 3) range forage and 1.2 kg cow-1 day-1 of a 30% wheat grain and 70% soybean meal:30% wheat supplement (36.0% crude protein); and 4) range forage with supplements in treatments 2 and 3 fed on alternate days. Meadow hay and soybean meal:wheat supplements provided 0.32 kg of crude protein/cow daily. Supplemented cows gained 3 to 53 kg body weight/year and maintained body condition, while control cows lost an average of 24.5 kg body weight/year and lost body condition. Intake of range forage was less (P < 0.05) by cows fed meadow hay and soybean meal:wheat supplements on alternate days than by cows on other treatments. Digestibility of range forage was lower (P < 0.05) for supplemented cows than control cows, but differences were small (avg. = 2%). Calving date, birth and weaning weights, and pregnancy rate were similar (P > 0.05) for all treatments. We concluded that subirrigated meadow regrowth grass hay was an effective alternative to traditional soybean meal-based supplements for maintaining body weight and body condition of gestating beef cows grazing winter range.
Key Words: subirrigated meadow, intake, digestibility, body condition