FORCE MEASUREMENTS IN WELFARE EVALUATION OF CATTLE HOUSING DESIGN

The force exerted on housing equipment by an animal may be used as a physical welfare parameter in the evaluation of housing design. This article is concerned with the force on a cow’s chest as she pushes against a self–locking feed barrier, as well as the force on the forelegs as she presses on the rear curb of the manger to reach her feed. The forces were determined in two experiments carried out with non–lactating cows of heavy breed. In the first experiment the force on the feed barrier was determined with the feed barrier placed either vertically or in a 20. inclined position combined with a manger width of either 1.20 or 0.62 m. The experiment showed that the force on the feed barrier remained low as long as the feed was kept within the cows’ reach in the narrow manger. With the wide manger, unacceptable forces were measured for both feed barrier positions. The inclined feed barrier allowed the cow to reach the feed at larger distances than the vertical feed barrier, however. In the second experiment the forces on both the feed barrier and the curb were determined for the same two feed barrier positions combined with a 135–, 200–, or 300–mm wide curb. Here a permanent manger width of 1.20 m was used. No serious forces were recorded on the curb in the case of inclined feed barrier as long as the curb width did not exceed 135 mm. For vertical feed barrier a curb width of up to 300 mm proved to be acceptable. For inclined feed barrier a curb width of 200 and especially 300 mm proved to be unacceptable. To avoid unacceptable forces on the cow’s chest a maximum manger width of 0.65 m is recommended for vertical feed barriers and 0.80 m for inclined feed barriers. To avoid unacceptable forces on the cows’ forelegs, a curb width of less than 200 mm is recommended for vertical feed barriers and 150 mm for inclined feed barriers.