A study of the herbage intake and efficiency of feed utilization of grazing cattle previously fed two winter planes of nutrition

Abstract

An experiment was conducted using 36 Hereford x Shorthorn bullocks of about 350 kg initial live weight. Winter planes of nutrition 13 December to 23 March were 'low' (hay only) and 'medium' (hay plus 1-8 kg concentrate); the former group of 18 bullocks lost on average 21-5 kg while the latter gained 26-5 kg. Each group was then stocked at 2-5 (low), 4-3 (medium) and 6-2 (high) bullocks per hectare and rotationally grazed on 10 plots, 7 of which contained H.I.-white clover mixture and the remaining 3 contained permanent pasture. Pasture digestibility and intake were determined for 16 weekly periods between early April and the end of September. Organic matter digestibility (OMD) of grazed herbage was determined in vitro on samples obtained by means of two rumen-fistulated bullocks. One gelatin capsule containing about 10 g of chromic oxide was daily administered to each bullock to estimate organic matter output. Winter feeding planes had no significant effect on OMD, and increasing the stocking rate increased herbage OMD only during the final 6 weeks. Significantly more organic matter was ingested during the grazing season by animals which had previously been fed on a low plane of nutrition. Stocking rates also significantly affected OMI. Bullocks fed on a low plane during winter were slightly more efficient subsequently in converting herbage into live-weight gain but this was a reflection of their lower average body weight; when feed efficiency was expressed on the basis of metabolic size, bullocks fed on a medium plane were more efficient in converting feed to liveweight gain. It is concluded that the higher daily gains on pasture of bullocks previously fed on a low plane is largely the result of a significantly higher feed intake by these animals.It has been observed that animals which are fed If increased herbage consumption accounts, at on a low or medium plane of nutrition during winter least in part, for the higher rate of gain full expresoutgain those fed on a high plane when all are sion to this potential should result from ungrazed during the subsequent summer (Meyer & restricted access to good quality pasture. More Clawson, 1964;Lawrence & Pearce, 1964). A full compensation, therefore, is to be expected when explanation for this phenomenon, however, is less animals are stocked at a low rather than a high readily available. Studies have been conducted on intensity and this has been demonstrated by Meyer the influence of winter feeding planes on subse-et al. (1965). The relative efficiency of animals quent responses of beef steers (Bohman, 1955; previously fed on two planes of nutrition, in terms Heinemann & van Keuren, 1956). Detailed experi-of converting herbage into meat, is of particular ments at the University of California (Meyer et al. importance where these animals reach slaughter 1965;Hull et al. 1965) have contributed much to weight at the end of the grazing season, our present understanding of this subject. TheseThe objectives of the present experiment were authors offer two explanations for th...

Comparative feeding value of forages from two cereal-legume based cropping systems for beef production from crossbred (Bos taurus × Bos indicus) steers and subsequent performance of underfed and realimented steers

“…This observation agreed with reports on cattle (O'Donovan, Conway and O'Shea, 1972;Ehoche, Alhassan, Umoh, Buvanendran and Umunna, 1992) and sheep (Lakpini, Adu, Buvanendran and Umunna, 1982) that restricted animals eat more per kg M during re-alimentation than unrestricted ones. Similarly, Butler-Hogg and Tulloh (1982) recorded greater compensatory growth with increased restriction of DM intake.…”

Relationship between live weight, age and dry-matter intake for beef cattle after different levels of food restriction

“…Holmes, Jones and Drake-Brockman (1961) found that in Ayrshire cows, heifers and calves, the relationship between intake and weight in animals weighing less than 180 kg was different from that found in heavier animals. O'Donovan, Conway and O'Shea (1972) obtained similar results with cattle, as did Torres (1971 and and Flores, Verde, Joandet, Gil and Torres (1974). They found a clear negative relationship between intake and live weight.…”

Effect of age of fattening and body condition of draught oxen fed teff straw (Eragrostis teff) based diets

“…However, the exact cause of the phenomenon in cattle has been the subject of much debate. Compensatory growth has been associated with reduced maintenance requirements (Saubidet and Verde, 1976;Ledger and Sayers, 1977), increased food intake (Meyer et al, 1965;O'Donovan et al, 1972;Wright et al, 1986Wright et al, , 1987 and changes in the composition of tissue gained (Meyer et al, 1965;Fox et aL, 1972;Baker et al, 1985).…”