Indigestion in young calves. V. The influence of grass silage and fine hay.

In an experiment with 24 young calves, lasting 45 days, all were fed a high lactose milk replacer causing some diarrhoea. Eight calves received grass silage and 8 fine hay in addition, while 8 received no solid supplement to the milk replacer (NS). Somewhat more (P < 0.05) dry matter was ingested from silage than hay. Weight gain was similar on the 2 supplements and much greater (P < 0.001) than on NS. Both silage and fine hay reduced (P < 0.01) the frequency of diarrhoea, approximately to the same extent. Further, silage or hay gave higher pH (P = 6.0.01 and 0.02, respectively) and less gram positive cocci and rods in the rumen fluid, better developed ruminai papillae and heavier (P < 0.01) empty reticulo-rumens than NS. Some calves fed silage had ulcers in the rumen, the same having occurred on fine hay in earlier experiments, but not in the present one. Althogether, the 2 roughages gave very similar results.