Urine features used to survey nitrogen excretion in rabbits

L. Gasco, L. Rotolo, G. Masoero, B. Miniscalbo, I. Zoccarato


The aim of this work was to estimate liquid and faecal nitrogen (N) excretion from rabbit herds using 2 clinical analyses of urine samples (urinary urea, UU and creatininury, CU) combined with the daily nitrogen intake (DNI) and metabolic weight of growing and lactating rabbit does. In the framework of 6 experiments, 81 growing rabbits, divided into 17 groups, weighing from 1.8 to 2.8 kg, and 18 multiparous lactating does, divided into 2 groups, were reared in metabolic cages. Five experimental groups of growing rabbits and one of lactating does received diets with lower crude protein content (from –8 to –19% less). The urine was collected (4-d and 1-d collection period for the growing rabbits and lactating does, respectively) and the daily weight (DUW: on av. 188±66 g/d), urinary urea (UU: 1012±463 mg/dL) and creatininury concentrations (CU: 46±25 mg/dL) were recorded. Lactating does showed higher DNI (+127%; P<0.001), which was excreted more in the faeces (DFN: +141%; P<0.001) than in the urine (DUN: +35%; P=0.36), compared to the growing rabbits on a daily per-capita basis. Consequently, the faecal-N to urine N ratio was higher for the does compared to growing rabbits (F/U: +93%; P<0.001). The percentage of retained N (PRN) for the lactating does and growing rabbits was not different (50.8 vs. 56.6%; P=0.31). Forward regression models were used to predict the daily nitrogen excretion. Successful r-square fit results were obtained (P<0.005) for the per-capita daily quantity of urinary N (DUN: R2=0.79) and faecal N (DFN: 0.93, mainly depending on DNI). The individual DNI was accurately fitted (R2=0.994; standard error=0.03), considering the 2 model estimates of the DUN and of the DFN, the metabolic weight and the type of animal. Relativising the N excreta as a percentage of the DNI, or as a ratio of the faecal –to urinary–N, led to less stable results of the regression models. The daily N intake, combined with the collection of urine samples and the measurement of urea and creatinine, led to a reliable estimate of the liquid N excretion.


nitrogen intake; nitrogen excretion; urine; urea; creatininury; rabbits

Full Text:



Aarnink A.J.A , Verstegen M.W.A. 2007. Nutrition, key factor to reduce environmental load from pig production. Livest. Sci., 109: 194-203. doi:10.1016/j.livsci.2007.01.112

Amber K.H., Yakout H.M., Hamed Rawya S. 2004. Effect of feeding diets containing yucca extract or probiotic on growth, digestibility, nitrogen balance and caecal microbial activity of growing new zealand white rabbits. In Proc.: 8th World Rabbit Congress, 7-10 September, 2004, Puebla, Mexico. 737-745.

Calvet S., Estellés F., Hermida B., Blumetto O., Torres A.G. 2008. Experimental balance to estimate efficiency in the use of nitrogen in rabbit breeding. World Rabbit Sci., 16: 205-211. doi:10.4995/wrs.2008.615

Ciszuk P., Gebregziabher T. 1994. Milk Urea as an Estimate of Urine Nitrogen of Dairy Cows and Goats. Acta Agriculturae Scandinavica, A, 44: 87-95. doi:10.1080/09064709409410187

ERM/AB-DLO. 1999. Establishment of criteria for the assessment of the nitrogen content of animal manures, European Commission, Final Report, Luxembourg.

Gidenne T., Lapanouse A., Segura M., Bannelier C., Tartié V. 2002. Effect of the dietary ratio “digestible fibre/crude protein” on rabbit nitrogen balance and on health status. COST Action 848, WG-1 and WG-4 joint meeting 2002, Ispra, Italy, 28.

Lebas F. 2010. Les reins et l'excrétion urinarie. In: Lebas, F. (ed.) La biologie du lapin. Available at: http://www.cuniculture.info/Docs/Biologie/biologie-06.htm

Maertens L., Cavani C., Petracci M. 2005. Nitrogen and phosphorus excretion on commercial rabbit farms: calculations based on the input-output balance. World Rabbit Sci. 13: 1-16. doi:10.4995/wrs.2005.533

Maertens L., Luzi F. 1996. Effect of dietary dilution on the performance and N-excretion of growing rabbits. In: Lebas, F. (ed.) Proceedings of 6th World Rabbit Congress, July 9-12, 1996, Toulouse, France, vol. 1. Association Francaise de Cuniculture, Lempdes, 237-241.

Masoero G., Baricco G., Cherubini R., Barge P., Sala G., de Poi E. 2008. Very low protein, aminoacid-supplied diet for heavy broiler rabbits: effects on nitrogen metabolism, and digital evaluation of excreta and products. In: Proc. 9th World Rabbit Congress, June 10-13, 2008, Verona, Italy, 729-734.

Masoero G., Miniscalco B., Mattioda R., Chicco R., Solomita M. 2011a. Relazioni fra escrezione urinaria, creatininuria e urea nel coniglio in accrescimento e nelle coniglie allattanti. Giornate di Coniglicoltura ASIC, 8-9 April, 2011, Forlì, Italy, 95-97.

Masoero G., Miniscalco B., Mattioda R., Chicco R., Solomita M. 2011b. Diete miniazotate integrate con Aminoacidi: prove di crescita e bilancio azotato. Giornate di Coniglicoltura ASIC, 8-9 April, 2011, Forlì, Italy.

Meineri G., Peiretti P.G., Masoero G., 2009. Appraisal of ingestion and digestibility in growing rabbits using near infrared reflectance spectroscopy (NIRS) of feeds and faeces. Ital. J. Anim. Sci., 8: 75-82

Moen R., Del Giudice G., 1997. Simulating Nitrogen Metabolism and Urinary Urea Nitrogen: Creatinine Ratios in Ruminants. J. Wildlife Manage., 61: 881-894. doi:10.2307/3802197

Nahm K.H. 2007. Feed formulations to reduce N excretion and ammonia emission from poultry manure. Bioresource Technol., 98: 2282-2300. doi:10.1016/j.biortech.2006.07.039

Núñez-Sánchez N., Martínez Marín A.L., Hernández M.P., Carrion D., Castro G.G., Pérez Alba L.M. 2012. Faecal near infrared spectroscopy (NIRS) as a tool to asses rabbit’s feed digestibility. Livest. Sci., 150: 386-390. doi:10.1016/j.livsci.2012.07.030

Oluokun J.A., 2005. Intake, digestion and nitrogen balance of diets blended with urea treated and untreated cowpea husk by growing rabbit. Afr. J. Biotechnol. 4: 1203-1208, Available online at http://www.academicjournals.org/AJB

Palomares J., Carabaño R., García-Rebollar P., De Blas J.C., García-Ruíz A.I 2006. Effects of dietary protein reduction during weaning on the performance of does and suckling rabbits. World Rabbit Sci., 14: 23-26. doi:10.4995/wrs.2006.545

Parigi-Bini R., Xiccato G., Cinetto M., Dalle Zotte A. 1992. Energy and protein utilization and partition in rabbit does concurrently pregnant and lactating. Anim. Prod., 55: 153-162. doi:10.1017/S0003356100037387

Pascual J.J., Tolosa C., Cervera C., Blas E., Fernández-Carmona J. 1999. Effect of diets with different digestible energy content on the performance of rabbit does. Anim. Feed Sci. Tech., 81: 105-117. doi:10.1016/S0377-8401(99)00052-8

Peiretti P.G., Masoero G., Meineri G. 2011. Effects of replacing palm oil with maize oil and Curcuma longa supplementation on the performance, carcass characteristics, meat quality and fatty acid profile of the perirenal fat and muscle of growing rabbits. Animal, 5: 795-801. doi:10.1017/S175173111000234X

Perez J.M., Lebas F., Gidenne T., Maertens L., Xiccato G., Parigi-Bini R., Dalle Zotte A., Cossu M.E., Carazzolo A., Villamide M.J., Carabaño R., Fraga M.J., Ramos M.A., Cervera C., Blas E., Falção-e-Cunha L., Bengala Freire J. 1995. European reference method for in vivo determination of diet digestibility in rabbits. World Rabbit Sci., 3: 41-43. doi:10.4995/wrs.1995.239

Rademacher M. 2000. How can diets be modified to minimize the impact of pig production on the environment?. AminoNews, by Degussa-Huls AG, Feed Additives Division, Hanau, DE, 1: 3-10.

Xiccato G., Trocino A., De Boever J.L., Maertens L., Carabaño R., Pascual J.J., Perez J.M., Gidenne T., Falção-e-Cunha L. 2003. Prediction of chemical composition, nutritive value and ingredient composition of European compound feeds for rabbits by near infrared reflectance spectroscopy (NIRS). Anim. Feed Sci. Technol., 104: 153-168. doi:10.1016/S0377-8401(02)00294-8

Xiccato G., Schiavon S., Gallo L., Bailoni L., Bittante G. 2005. Nitrogen excretion in dairy cow, beef and veal cattle, pig, and rabbit farms in Northern Italy. Ital. J. Anim. Sci., 4: 103-111.

Xiccato G., Trocino A., Fragkiadakis M., Majolini D. 2007. Indagine sugli allevamenti di conigli in Veneto: risultati di gestione tecnica e stima dell’escrezione azotata. Giornate di Coniglicoltura ASIC, 26-27 september, 2007, Forlì, Italy, 115-117.

Zoccarato I., Gasco L., Schiavone A., Guo K., Barge P., Rotolo L., Savarino G., Masoero G. 2008. Effect of extract of chestnut wood inclusion (Enc®) in normal and low protein aminoacid supplemented diets on heavy broiler rabbits. 9th World Rabbit Congress, June 10-13, 2008, Verona, Italy, 873-878

Zunino V., Meineri G., Peiretti P.G. 2010. Curcuma longa and dietary plant oils for growing rabbits: Effect on apparent digestibility. J. Food Agric. Environ. 8: 435-438.

Abstract Views

Metrics Loading ...

Metrics powered by PLOS ALM


 Universitat Politècnica de València


Official journal of the World Rabbit Science Association (WRSA)


e-ISSN: 1989-8886     ISSN: 1257-5011   https://doi.org/10.4995/wrs