Evaluation of Two Mills for Cattle Waste Grinding for Pig Feeding/Evaluación de dos molinos para triturado de desechos de vacunos para la alimentación de cerdos

Pig production in Venezuela has been affected by the high costs of concentrated feed. An alternative to reduce production costs in feeding pigs is the use of cattle bones, due to their high protein content and other properties that lead to a good diet in the pig fattening process. The evaluation of the working organs of two mills in the crushing of cattle bones was carried out, determining the quality of crushing and energy consumption. The granulometry and impact energy on the Sharpy pendulum were determined. A [2.sup.3] factorial type experimental design, dispersion curves and Pareto bars were applied. The controlled variables were type of mill, wet mass and type of bone and the response variables were sieved mass, grinding time, engine revolutions and humidity. The physical and mechanical properties as well as length, dry mass, wet mass, force and effort were determined. Finger and nose mills and hammer mills were compared for grinding quality and energy consumption. The hammer mill was found to have higher efficiency.