Effect of unwilted and wilted silages and hay, supplemented with different amounts of concentrate, on live-weight gain of calves

Abstract

Three experiments were carried out to investigate the effect of different forage types on the performance of male British Friesian calves up to 6 months of age. Unwilted and wilted silages were compared in all experiments, and in experiment 1 hay was also compared with the two silages. All the forages were compared at different levels of concentrate supplementation ranging, in different experiments, from none to ad libitum.Calves fed wilted silage consumed 490, 90 and 200g/kg more forage dry matter respectively than those fed unwilted silage in the three experiments but this extra intake was generally not reflected in an increased rate of gain. Hay which was of lower digestibility than silage gave significantly lower live-weight gain. Quantities of silage consumed at an early age were small, with a mean daily intake over the first five weeks of 0·13 kg dry matter. Concentrate reduced silage dry-matter intake by 0·49 kg/kg concentrate dry matter consumed. Estimated mean concentrate intake required to achieve a daily gain of 0·75 kg in 1- to 6-month-old calves with silage offered ad libitum was 0·83 kg dry matter.

Microstructure of skeletal muscles of growing calves fed silage-based vs hay-based diets. I. Fibre diameters

“…Krosowski and KTosowska (1984) and KTosowski et al (1988) reported that the faster the animals' growth as affected by feeding, the larger the fibre diameter and higher the percentage of FTG fibers. In growing calves reared on hayfree low-concentrate diets based on grass silage, satisfactory gains have been reported (Marsh, 1975(Marsh, , 1976Bartholomew et al, 1981;Bidwell-Porgbska et al, 1987;Piotrowski et al, 1988) (Ziegan, 1979 (Brooke, 1970) In the younger calves the intake of crude protein (CP) and gross energy (GE) was also slightly higher in the SD fed group. In the older animals the daily intake of GE was considerably higher, while the intake of CP was lower in the SD than in the HD fed group (table I).…”