title: [Utilization of 15N-labelled urea by laying hens. 1. Survey of the literature, 15N-excretion in feces and urine].
abstract: Three colostomated leghorn hybrids with an average laying performance of 75% received a ration with 17.7% crude protein and an energy content of 519 energetic feed units for hens per kg mixed feed over a period of 8 days. In the first six days of the experiment the 1%-supplement of urea to the ration was labelled. Its atom-% 15N excess (15N') amounted to 96.06%. During the last two days the urea supplement was not labelled. The total N, trichloracetic acid (TCA)-soluble N and the ammonia N were determined in the feces samples collected daily. In the urine samples collected daily the total N, urea N and ammonia N per hen were determined as well. In all samples the atom-% 15N excess (15N') was measured. The percentage of 14N in feces of the 14N dose was, on an average of the three hens, 21.3% and the analogous quota of 15N' 4.6%. The quota of ammonia 14N of the total 14N in feces had an average of 2.5%, the corresponding 15N' quota was 10.1%. The atom-% 15N' of the urea N in urine was considerably above that of the total urine N and had a maximum of more than 50%. The quota of urine 14N of the 14N taken in had an average of 44.4%, and the corresponding 15N' quota was 56.9%. On an average of the three hens, 61.6% of the 15N' were excreted in feces and urine during the 8-day test period.
mesh_terms: D000641:Ammonia / Q000378:metabolism; D000818:Animals; D002645:Chickens / Q000378:metabolism*; D005243:Feces / Q000378:metabolism*; D005260:Female; D009584:Nitrogen / Q000378:metabolism; D009587:Nitrogen Isotopes; D014508:Urea / Q000378:metabolism* / Q000652:urine
chemical_list: D009587:Nitrogen Isotopes; D000641:Ammonia; D014508:Urea; D009584:Nitrogen
vernacular_title: Zur Verwertung von 15N-markiertem Harnstoff bei der Legehenne. 1. Mitteilung. Literaturübersicht, 15N-Exkretion über Kot und Harn.