Nitrogen Balance and Uric Acid Excretion in Lohmann-Brown Hens Fed Diets with Different Crude Protein and Metabolizable Energy Levels

  • Mădălina CIOARIC (DEGENARO) U.A.S.V.M. of Bucharest, 59 Marasti Blvd, District 1, 011464 Bucharest, RO
  • Rosalie BĂLĂCEANU D.S.V.S.A. Ilfov, 8 Ion Ionescu de la Brad str., District 1 013811 Bucharest, RO
  • Andrei Tudor KACENCO U.A.S.V.M. of Bucharest, 59 Marasti Blvd, District 1, 011464 Bucharest, RO
  • Ivona ZĂBAVĂ U.A.S.V.M. of Bucharest, 59 Marasti Blvd, District 1, 011464 Bucharest, RO
  • Ilinca IOZON U.A.S.V.M. of Cluj Napoca, 3-5 Mănăștur str., 400372 Cluj Napoca,
  • Nicolae DOJANĂ U.A.S.V.M. of Bucharest, 59 Marasti Blvd, District 1, 011464 Bucharest, RO
DOI: https://doi.org/10.15835/10.15835/buasvmcn-vm:2024.0008
Keywords: Diet crude protein content; diet metabolizable energy content; laying hens; nitrogen balance.

Abstract

This study aimed to determine the effect of dietary metabolizable energy (ME) and crude protein (CP) levels on nitrogen excretion and laying performance in laying hens. Four groups of 20-week-old Lohmann hens were fed different ME and CP level diets, expressed as higher (H) or lower (L) versus control: group HME/HCP (2,820 kcal ME/16.7% CP), group HME/LCP (2,820 kcal/14.8% CP), group LME/HCP (2,690 kcal/16.7% CP) and group LME/LCP (2,690 kcal/14.8% CP). The control group was fed a commercial diet (2,754 kcal/15.5% CP). Experimental feeding lasted 12 weeks. Egg production was significantly improved (P=0,015) in HME/HCP group. Feed conversion ratio was significantly lower (P=0.013) in HCP groups versus control). The amount of uric acid excreted by HCP groups was 40% higher versus LCP groups (P=0.000) and excreted uric nitrogen was 24.2% higher in HCP versus LCP groups (P=0.001). HCP groups excreted 0.43 g/cap./day more nitrogen versus LCP groups (P=0.001). HCP groups retained 0.21 g/egg mass/day more nitrogen versus LCP groups. ME-supplements did not significantly modify the amount of nitrogen excretion.  In conclusion, the tested CP diet supplementations increase faecal nitrogen excretion and egg-retained nitrogen in layers. Effect on laying performances depends of CP level and CP/ME ratio in the diet.             

Published
2024-11-15
Issue
Vol. 81 No. 2 (2024): BULLETIN OF UNIVERSITY OF AGRICULTURAL SCIENCES AND VETERINARY MEDICINE CLUJ-NAPOCA. VETERINARY MEDICINE
Section
Research Articles
 Authors who publish with this journal agree to the following terms:

a) Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.

b) Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.

c) Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).