Beziehungen Zwischen der 15N-Exkretion über den Kot nach Oraler 15N-Harnstoffaufnahme und der Blutharnstoffkonzentration in Abhängigkeit von der Rohfaseraufnahme bei Schweinen

Publisher Website
Google Scholar
Abstract
9 pigs of a live weight at the beginning of the experiment of 33 kg received in 3 consecutive series of experiments (3 animals/group) a basic barley ration of 1.0-1.2 kg per animal and day. In groups 1 to 9 the following supplements were given: 1=without N-supplement, 2=10.5 g urea, 3=79 g dried skin milk, 4=11 g area, 5=without N-supplement, 6=110 g horse bean coarse meal, 7=without N-supplement, 8=95 g dried skim milk, 9=120 g horse bean coarse meal. In groups 1-6 the ration was supplemented with 150-165 g DM partly hydrolyzed straw mean per animal and day. After 20 days the animals received a single dose of 0.5 g/kg0.75 15N-urea (72.1 atom-% 15N-excess) with the morning meal of the first day of the experiment. During the four days of the experiment groups 1-6, due to the straw meal supplement, excreted significantly higher N-amounts than the corresponding groups 7-9. In comparison with the first day of the experiment (1 h after the morning meal) urea concentration in the blood decreased to the following percentage in the sequence 1-9:64; 65; 77; 54: 64; 73; 82; 88; 84 on the second day of the experiment (1 h before the evening meal). Between the excretion of 15N-excess in faeces (y=mg) during the four days of the experiment and the concentration of urea in the blood (x=mmol/l) there was the following significant negative correlation: y= -40.1 x + 340. Urea elimination by means of urea inflow into the large intestine and subsequent bacterial protein synthesis (in the presence of fermentable crude fibre) significantly decreased urea concentration in the blood.