Marco Antonio Esnaola L.1 y José Alberto Ochoa2
The use of rations based on barley and fish meal was studied on growing and fattening pigs. Different percentages of the fish meal protein were substituted by rapeseed meal. Results indicate that increasing the level of rapeseed meal in the ration produced smaller liveweight increase, a decrease in feed consumption, loss of the feed efficiency and larger thyroid glands and liver. The rapeseed meal did not have any eífect on carcass characteristics.
Rapeseed meal can complete economically with fish meal at substitution levels of 75 and 100 per cent. This is caused by a reduction in feeding costs of and 6 per cent, respectively. However, this results in larger periods to reach market weight of 22 and 28 days, thus the benefits of using rapeseed meal will depend on the price relationship to fish meal and the rate of gain desired in arder to get the pigs to market at a given date.
1Ing. Agr. Proyecto Producción Porcina. Estación Experimental Carillanca. Instituto de Investigaciones Agropecuarias, Casilla 58-D, Temuco, Chile.
2Memorante, Estudiante Agronomía. Universidad Católica de Valparaíso.