Gustavo Cubillos O.1 y Alberto Ferrando F.2
A grazing trial was conducted at the Carillanca Experiment Station to compare five forage mixtures for beef production under irrigated condition at Cautín province. The mixtures used were red clover (Trifolium pratense L.) and perennial ryegrass (Lolium perenne L.) red clover and orchardgrass (Dactylis glomerata L.) ladino clover (Trifolium repens L.) and ryegrass, ladino clover and orchardgrass,and ladino clover and fescue (Festuca arundinácea L.).
The experimental plots were grazed starting the second year afier establishment in a rotational scheme and variable stocking. Dates of grazing were from December to April and October to April in the first andsecond year was 112 and 180 days in years first and second. There was no statistical difference in animal daily gain, thus reflecting a management system which turn· out to be near the optiment grazing pressure. There were no statistical difference in carrying capacity and beef out put per hectare indicating a .similar potential fOI all mixtures used in the experimental.
Forage consumption in a dry matter basis estimated through sampling gave erratic figures. This shows the need for larger samples or a special device to estimate more accurately forage availability. No statistical difference was detected in TDN consumption calculated based in live weight increase and the conduction of the animal.
Botanical composition of the pastures showed a good balance of species in the first year of the experimental. Red clover showed a significant decrease as component of the sward at the end of the second grazing season (third year after establishment). Ladino clover stayed in the mixtures showing his condition of a perennial legume.
1Ing. Agr. Ph. D., Coordinador Zootecnia. Instituto de Investigaciones Agropecuarias, Casilla 5427, Santiago. Profesor de la Facultad de Agronomía de la Universidad Católica de Chile y Católica de Valparaíso.
2Ing. Agr. Proyecto Producción Bovina, Estación Experimental Carillanca. Dirección actual Corporación de la Reforma Agraria. Temuco.