Feed intake of grazing Friesian bulls

D.A. Clark, R.W. Brougham

Grasslands Division, DSIR, Palmerston North

Proceedings of the New Zealand Society of Animal Production. 1979, 39: 265-274

The digestible organic matter intakes of two groups of 12 Friesian bulls stocked at 7.4/ha were estimated each month for 2 years by the chromic oxide dilution and difference techniques. There was no significant difference between the two methods. The average daily ME intake was 47.3 MJ. The annual requirement of a Friesian bull growing from 90 to 330 kg was 17,027 MJ of ME (1470 kg DM), a conversion efficiency of 6.9 kg DM/kg liveweight gain.

Seasonal intakes were 3.50, 3.21, 3.16 and 6.22 kg DM/bull/day for summer, autumn, winter and spring. Pasture allowances varied from 2.9 to 11.8 kg OM/100 kg LW/day in summer and autumn and from 2.1 to 4.6 in the winter and spring. In vitro organic matter digestibilities varied from 62 to 79% in summer and autumn and 67 to 82% in winter and spring. Daily liveweight gain was linearly related to allowance in winter and spring (0.6 kg/kg OM/100 kg LW), but quadratically related in summer and autumn with a maximum at 8.5 kg OM/100kg LW), but quadratically related in summer and autumn with a maximum at 8.5 kg OM/100 kg LW/day. Organic matter digestibility was related to liveweight gain (0.036 kg/% OMD) in the summer and autumn but had no effect in winter and spring.

Keywords: NZSAPAB;

Last Updated 12-09-1998