
TY  - JOUR
A1  - Leibholz, J 
T1  - The development of ruminant digestion in the calf. II.* The digestion of barley and urea
JF  - Australian Journal of Agricultural Research
JO  - Aust. J.  Agric. Res.
Y1  - 1978
VL  - 29
IS  - 6
SP  - 1293
EP  - 1299
KW  - 
UR  - https://doi.org/10.1071/AR9781293 
N2  - Two Friesian calves were fitted with re-entrant cannulae in the duodenum and four Friesian calves were fitted with re-entrant cannulae in the duodenum and terminal ileum within 1 week of birth. At 35 days of age the calves were weaned from milk and offered a diet containing 72&#37; barley, 3.5&#37; urea and 15 % wheat chaff. Total collections of digesta flowing from the duodenum and ileum were made for 12 hr at weekly intervals for 6 weeks after weaning. Of the dry matter ingested, 26&#37; was apparently digested in the stomach 1 week after weaning, 40&#37; by 2 weeks after weaning and increasing to 51&#37; by 6 weeks after weaning. The flow of nitrogen to the duodenum was greater than the nitrogen intake in the first week after weaning, and it gradually decreased to 83&#37; of the nitrogen intake by 6 weeks after weaning. During this period the contribution of microbial nitrogen to the nitrogen flow increased from 28 to 71&#37;. The apparent absorption of amino acids from the small intestine increased with increasing feed intake, but the uptake of methionine was less than the methionine requirement for growth.  _________________ * Part I, Aust. J. Agric. Res., 26: 1081 (1975). 
ER  -

