Aspects of diet selection and parasitology of grazing calves: A dissertation submitted in partial fulfilment of the requirements for the degree of Bachelor of Agricultural Science (Hons) in the University of Canterbury [Lincoln College]

Abstract

The grazing behaviour and selective ability of animals means that parameters of the diet selected will differ from those of the available sward.

The first trial will examine the in vitro digestibility, proportion of plant parts and numbers of parasitic larvae in the oesophageal fistula extrusae from the nine month Friesian steer calves, Comparisons will be made with the same parameters measured on the herbage available for grazing.

Similar experimental work has been carries out with older cattle on subtropical pastures (Chacon and Stubbs, 1976; Ellis, 1979). The most comparable work is that reported by Jamieson and Hodgson (1979a and b). They examined some of these parameters, for calves on temperate pastures, under conditions of increasing grazing pressure.

In the second trail, the liveweight gain responses of nine-month Friesian steer calves is examined, comparing two-weekly and six-weekly anthelmintic drenching. This experiment was carried out over a 12 week period in the late autumn/winter.