Nutritive value of citrus co-products in rabbit feeding

J. Carlos de Blas, Pablo Ferrer, Carlos Alberto Rodríguez, Alba Cerisuelo, Paloma García-Rebollar, Salvador Calvet, Carlos Farias


Pulps from different citrus fruits are relevant agro-industrial co-products in the Mediterranean area in terms of amounts produced and availability. Moreover, part of the product is dehydrated, which increases its interest in monogastric species such as rabbits. Seventy eight samples from various Spanish producers using several types of fresh fruits (orange, tangerine, lemon and pomelo) and different processing methods of orange and tangerine samples (either fresh or dried after adding Ca(OH)2) were analysed for their chemical composition and in vitro digestibility. Average dry matter (DM) contents of ash, neutral detergent fibre, acid detergent fibre, acid detergent lignin (ADL), soluble fibre, crude protein (CP), insoluble neutral and acid detergent CP, ether extract and gross energy were 49.0, 226, 139, 12.1, 213, 71.2, 13.1, 4.2, 30.5 g and 17.8 MJ/kg DM, respectively. Mean DM and CP in vitro digestibility were 86.7 and 95.6%, respectively. Digestible energy was estimated to be 15.1 MJ/kg DM. A high variability (coefficient of variation from 17% for CP to 60% for ADL) was observed among the samples for most of the traits studied, which was partially explained by the effects of type of fruit and processing. Lemon pulps had on average higher ash and fibre but lower sugar contents than the other pulps. Dehydration processes increased ash content (almost double than for fresh pulp) due to lime addition. As regards the current results, citrus pulp has potential for use in rabbit diets as a source of energy and soluble fibre.


citrus pulp; type of fruit; processing; nutritive value; rabbits

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Abad R., Ibáñez, M.A., Carabaño, R., García, J. 2013. Quantification of soluble fibre in feedstuffs for rabbits and evaluation of the interference between the determinations of soluble fibre and intestinal mucin. Anim. Feed Sci. Technol., 182: 61-70.

Aba, R. 2015. Identification of the method to quantify soluble fibre and the effect of the source of fibre on the ileal and faecal digestibility of soluble and insoluble fibre in rabbits. PhD Thesis, UP Madrid.

Antezana, W., Calvet, S., Beccaccia, A., Ferrer, P., De Blas, C., García-Rebollar, P., Cerisuelo, A. 2015. Effects of nutrition on digestion efficiency and gaseous emissions from slurry in growing pigs: III. Influence of varying the dietary level of calcium soap of palm fatty acids distillate with or without orange pulp supplementation. Anim. Feed Sci. Technol., 209: 128-136.

AOAC, 2000. Official Methods of Analysis, 17th ed. Association of Official Analytical Chemists, Washington, DC.

Bampidis V.A., Robinson P.H. 2006. Citrus by-products as ruminant feeds: A review. Anim. Feed Sci. Technol., 128: 175-217.

Beccaccia A., Calvet S., Cerisuelo A., Ferrer P., García-Rebollar P., De Blas C. 2015. Effects of nutrition on digestion efficiency and gaseous emissions from slurry in growing pigs: I. Influence of the inclusion of two levels of orange pulp and carob meal in isofibrous diets. Anim. Feed Sci. Technol., 208:158-169.

Boisen, S. 1991. A model for feed evaluation based on in vitro digestibility dry matter and protein. In: Fuller, M.F. (Ed.), In vitro Digestion for Pigs and Poultry. CAB International, Wallington, 135-145.

Braddock R.J. 1999. Handbook of citrus by-products and processing technology. John Wiley & Sons Inc. CVB. 2016. Veevoedertabel (Livestock Feed Table) Centraal Veevoeder Bureau, Lelystad. The Netherlands.

De Blas J.C., Villamide M.J. 1990. Nutritive value of beet and citrus pulps for rabbits. Anim. Feed Sci. Technol., 31: 239-246.

De Blas J.C., Wiseman J., Fraga M.J., Villamide M.J. 1992. Prediction of the digestible energy and digestiblity of gross energy of feeds for rabbits. 2. Mixed diets. Anim. Feed Sci. Technol. 39: 39-59.

De Blas J.C., Mateos G.G. 2010. Feed formulation. In: J.C. de Blas and J. Wiseman (eds.) The nutrition of the rabbit (2nd ed), 222-232. CABI Publishing CAB International, Wallingford, UK.

De Blas J.C., Chamorro S., García-Alonso J., García-Rebollar P., García-Ruiz A.I., Gómez-Conde M.S., Menoyo D., Nicodemus N., Romero C., Carabaño R. 2012. Nutritional digestive disturbances in weaner rabbits. Anim. Feed Sci. Technol., 173: 102-110.

De Blas, J.C. 2013. Nutritional impact on health and performance in intensively reared rabbits. Animal, 7: 102-111.

FAOSTAT. 2017. Food and agriculture data. Food and Agriculture Organization of the United Nations. Available at Accessed May 2017.

FEDNA. 2010. Tablas Fedna de composición y valor nutritivo de alimentos para la fabricación de piensos compuestos. 3ª ed. C. de Blas, G.G. Mateos, P. García-Rebollar (eds), 502.

Fraga M.J., Pérez de Ayala P., Carabaño R., de Blas C. 1991. Effect of type of fiber on the rate of passage and on the contribution of soft feces to nutrient intake of finishing rabbits. J. Anim. Sci., 69: 1566-1574.

Garau M.C., Simal S., Rossello C. Femenia A. 2007. Effect of airdrying temperature on physico-chemical properties of dietary fibre and antioxidant capacity of orange (Citrus aurantium v. Canoneta) by-products. Food chemistry, 104: 1014-1024.

García J., Carabaño R., Pérez Alba L., De Blas J.C. 2000. Effect of fiber source on cecal fermentation and nitrogen recycled through cecotrophy in rabbits. J. Anim. Sci., 78: 638-646.

Gidenne T., Carabaño R., García J, de Blas C. 2008. Fibre digestion. In: J.C. de Blas and J. Wiseman (eds.) The nutrition of the rabbit (2nd ed), 66-82. CABI Publishing CAB International, Wallingford, UK.

Gidenne T. 2015. Dietary fibres in the nutrition of the growing rabbit and recommendations to preserve digestive health: a review. Animal, 9: 227-242.

Heuzé V., Tran G., Hassoun P., Lebas F. 2017. Citrus pulp, dried. Feedipedia, a programme by INRA, CIRAD, AFZ and FAO, Available at Last updated on January 1, 2017, 17:52.

Licitra, G., Hernández, T.M., Van Soest, P.J. 1996. Standardization of procedures for nitrogen fractionation of ruminant feed. Anim. Feed Sci. Technol. 57, 347-358.

MAPAMA. 2017. Anuario de Estadística 2015. Ministerio de Agricultura, Pesca, Alimentación y Medio Ambiente. Available at Accessed May 2017.

Martínez-Pascual J.L. 1977. Utilización de la pulpa de cítricos en la alimentación de terneros, corderos y conejos. PhD Thesis, ETSIA, Valencia.

Martínez-Pascual, J.L and Fernández-Carmona, J. 1980a. Citrus pulp in diets for fattening rabbits. Anim. Feed Sci. Technol., 5: 23-31.

Martínez-Pascual J.L., Fernández-Carmona J. 1980b. Composition, digestibility, nutritive value and relations among them of several feeds for rabbits. In Proc.: II Rabbit World Congress, Barcelona, 214-223.

Mertens D.R., Allen M., Carmany J., Clegg J., Davidowicz A., Drouches M., Frank K., Gambin D., Garkie M., Gildemeister B., Jeffress D., Jeon C.S., Jones D., Kaplan D., Kim G.N., Kobata S., Main D., Moua X., Paul B., Robertson J., Taysom D., Thiex N., Williams J., Wolf M. 2002. Gravimetric determination of amylase-treated neutral detergent fiber in feeds with refluxing in beakers or crucibles: Collaborative study. J. AOAC Int., 85: 1217-1240.

Pérez de Ayala P., Fraga M.J., Carabaño R., de Blas J.C. 1991. Effect of fiber source on diet digestbility and growth in fattening rabbits. J. Appl. Rabbit Res., 14: 159-165.

Ramos M.A., Carabaño R., Boisen S. 1992. An in vitro method for estimating digestibility in rabbits. J. Appl. Rabbit Res., 15: 938-946.

SAS Institute. 2008. SAS/STAT® User’s guide, version 9.3. SAS Institute Inc., Cary, NC.

SIA. 2017. Servicio de Información sobre alimentos. Available at Accessed January 2017.

Trocino A., García J., Carabaño R., Xiccato G. 2013. A metaanalysis on the role of soluble fibre in diets for growing rabbits. World Rabbit Sci., 21: 1-15.

USDA. 2016. Citrus Fruits 2016 Summary. National Agricultural Statistics Service. United States Department of Agriculture.

Van Soest P.J., Robertson J.B., Lewis B.A. 1991. Methods for dietary fibre, neutral detergent fiber, and non starch polysaccharides in relation to animal nutrition. J. Dairy Sci., 74: 3583-3597.

Villamide M.J., Carabaño R., Maertens L., Pascual J., Gidenne T., Falcão-E-Cunha L., Xiccato, G. 2009. Prediction of the nutritional value of European compound feeds for rabbits by chemical components and in vitro analysis. Anim. Feed Sci. Technol., 150: 283-294.

Wiseman J., Villamide M.J., de Blas J.C., Carabaño R. 1992. Prediction of the digestible energy and digestibility of gross energy of feeds for rabbits. 1. Individual classes of feeds. Anim. Feed Sci. Technol., 39: 27-38.

Yemm E.W., Willis A.U. 1954. The estimation of carbohydrates in plant extracts by anthrone. Biochem. J., 57: 508-514.

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World Rabbit Science  vol: 27  issue: 1  first page: 15  year: 2019  
doi: 10.4995/wrs.2019.10450


 Universitat Politècnica de València


Official journal of the World Rabbit Science Association (WRSA)


e-ISSN: 1989-8886     ISSN: 1257-5011