The milk requirements of the newborn calf

Self Cite

Section: Management and Feedingmentioning

confidence: 99%

The protein requirement of the ruminant calf. I. The effect of protein content of the concentrate mixture on the performance of calves weaned at an early age

Stobo¹,

Roy²,

Gaston³

1967

Self Cite

“…RELIABLE estimates of the protein and energy requirements of milk fed calves have been obtained from the calorimetric and nitrogen balance studies carried out by Blaxter (1950), Blaxter and Wood (1951a, 1951b, 1952a, 1952b, Roy, Huffman and Reineke (1957), Cunningham and Brisson (1957), Brisson, Cunningham and Haskell (1957), Cunningham et al (1958), and Roy et al (1958). No such information is available for the ruminant calf which has been weaned from milk at an early age and fed subsequently on solid food.…”

Section: Rowett Research Institute Bucksburn Aberdeenmentioning

confidence: 99%

The nutrition of the early-weaned calf. I. The effect on nitrogen retention of diets containing different levels of groundnut meal

Whitelaw¹,

Preston²,

Ndumbe³

1961

1. Nitrogen balance studies were made on eight early weaned calves given diets varying in crude protein content from 11·6% to 22·6% in dry matter.2. Nitrogen retention increased significantly as the level of crude protein increased to 19·20%; there was no further increase in nitrogen retention when the level of protein was increased to 22·6%.3. Dry matter digestibility and apparent digestibility of dietary nitrogen rose progressively as the level of crude protein increased.4. The nitrogen retention of calves fed diets adequate in protein was calculated to be 2·88 g. per 100 g. gain in body weight.

“…The high-and low-protein concentrate mixtures (treatments 17 and 18) were the same as those described previously (Stobo et ah, 1967a), and in treatment 19 the amount of urea calculated to raise the crude protein content from 12% to 20% was added to the low-protein concentrate. They were given sufficient whole milk for maintenance (Roy, Shillam, Hawkins and Lang, 1958) from 3 weeks until they were weaned abruptly at 5 weeks of age. concentrates, and refusals were discarded every second day.…”

mentioning

confidence: 99%

The protein requirement of the ruminant calf. III. The ability of the calf weaned at five weeks of age to utilise urea given as a supplement to a low-protein concentrate

Stobo¹,

Roy²,

Gaston³

1967

(1) Forty-five Ayrshire and Shorthorn bull calves were used in an experiment to study the ability of the calf weaned at 5 weeks on to concentrates, hay and water, to utilise urea added to a low-protein concentrate.(2) Calves given the concentrate containing 20% crude protein gained weight significantly faster from 3 to 12 weeks than those given concentrates containing either 12% crude protein, or 18% crude protein of which 33% was in the form of urea. There was a tendency for calves given the urea supplement to gain weight at a slightly faster rate to 8 weeks than those given the low-protein diet, but this tendency was reversed between 8 and 12 weeks of age.(3) At 15 weeks, the coefficients of apparent digestibility of dry matter, crude protein, crude fibre and nitrogen-free extract were significantly greater when an all-concentrate diet containing 19·6% crude protein was given, than with a concentrate containing 12·2% crude protein. When the lowprotein concentrate supplemented with urea was given (18·5% crude protein) the apparent digestibility of dry matter, crude protein and ether extract was significantly greater than on the low-protein concentrate. The digestibility of crude fibre in the urea-supplemented diet was intermediate between the values obtained on the high- and low-protein diets.(4) Despite marked differences between treatments in the intakes of apparently digested nitrogen, similar amounts of nitrogen were retained, because of large differences in the amounts of nitrogen excreted in the urine. However, the amount of nitrogen stored per unit of body-weight gain was 27% higher in calves given the concentrate containing 19·6% crude protein than in those given either the low-protein concentrate or the urea-supplemented diet.