SciELO - Scientific Electronic Library Online

vol.11Development and validation of two immunoassays for the detection of Brucella canis in dogsEffect of marine sulfurized polysaccharides as immunomodulators of the response to vaccination in broilers author indexsubject indexsearch form
Home Pagealphabetic serial listing  

Services on Demand




Related links

  • Have no similar articlesSimilars in SciELO


Abanico veterinario

On-line version ISSN 2448-6132Print version ISSN 2007-428X

Abanico vet vol.11  Tepic Jan./Dec. 2021  Epub Apr 04, 2022 

Short communication

The protein and fiber content of tropical forages does not affect its preference by fattening rabbits

María Milla-Luna1

Luis Cruz-Bacab*  1

Santiago Ramírez-Vera1

Guadalupe Arjona-Jiménez1

Cecilia Zapata-Campos2

1División Académica de Ciencias Agropecuarias - Universidad Juárez Autónoma de Tabasco. Tabasco, México.

2 Facultad de Medicina Veterinaria y Zootecnia “Norberto Treviño Zapata” - Universidad Autónoma de Tamaulipas. Carretera Victoria-Mante Km 5, Cd Victoria Tamaulipas. México.


The objective of this research was to evaluate the preference for forages commonly used in animal feed in tropical areas of Mexico. Forages of Guasimo (Guazuma ulmifolia), Cocohite (Gliricidia sepium), Swirl grass or Bahiagrass (Paspalum notatum), Egypt grass (Brachiaria mutica), and Humidicola grass (Brachiaria humidicola) were offered simultaneously to 24 New Zealand rabbits for 14 days. In this investigation it was shown that Gliricidia sepium and Brachiaria mutica were preferred compared to Guazuma ulmifolia, Paspalum notatum and Brachiaria humidicola (P <0.05). The consumption of crude protein, acid detergent fiber, and neutral detergent fiber were higher with Gliricidia sepium and Brachiaria mutica (P <0.05). In conclusion, fattening rabbits preferred Gliricidia septum, and Nutrient content was not related to consumption preference. Forage preference study and its relationship with nutritional content are necessary to include tropical resources in rabbit feeding.

Keywords: Brachiaria; Gliricidia sepium; Guazuma ulmifolia; intake; Paspalum notatum


El objetivo de esta investigación fue evaluar la preferencia de forrajes empleados comúnmente en la alimentación animal en zonas tropicales de México. El forraje de guasimo (Guazuma ulmifolia), cocohite (Gliricidia sepium), pasto remolino (Paspalum notatum), pasto Egipto (Brachiaria mutica) y pasto humidicola (Brachiaria humidicola) fueron ofrecidos simultáneamente a 24 conejos Nueva Zelanda durante 14 días. En esta investigación se demostró que Gliricidia sepium y Brachiaria mutica fueron preferidos en comparación con Guazuma ulmifolia, Paspalum notatum y Brachiaria humidicola (P<0.05). El consumo de proteína cruda, fibra detergente ácido, y fibra detergente neutro fueron mayores con Gliricidia sepium y Brachiaria mutica (P<0.05). En conclusión, Gliricidia sepium fue preferido por conejos de engorda. El contenido de nutrientes no tuvo relación con la preferencia de consumo. El estudio de la preferencia de forrajes y su relación con su contenido nutricional es necesario para la inclusión de recursos tropicales en la alimentación de conejos.

Palabras clave: Brachiaria; consumo; Gliricidia sepium; Guazuma ulmifolia; Paspalum notatum


The need for animal protein in developing countries has generated growing interest in the study of alternative, cheap and available food sources for animal production (Nieves et al, 2011; Malavé et al, 2013). In tropical areas around the world, a wide variety of plant species with potential for feeding herbivores, such as rabbits, have been identified, considering their availability, biomass production and chemical composition (Nieves et al, 2011; Malavé et al, 2013). Different studies conducted in Latin America and the world, show that the inclusion of tropical forages in the feed of fattening rabbits allows obtaining satisfactory productive yields (Nieves et al, 2011); however, the information generated on the preference of these resources in rabbits is still scarce (Safwat et al, 2014; Hafsa et al, 2016). Feed consumption and preference in rabbits have been evaluated under farm and laboratory conditions, demonstrating that it is influenced by multiple factors, including fiber content, digestible energy, fat, amino acid composition, gut fill, and the physical form of the consumed material and environmental conditions (Prebble & Meredith 2014). The simultaneous forage offering method is the closest to reality for determining forage preference in rabbits (Safwat et al, 2014). The study of forage preference may favor the development of local resource-based rabbit production in tropical areas (Safwat et al, 2014; Ozakwe & Ekwe, 2017).

The objective of the present study was to evaluate the preference of tropical forages in fattening rabbits and the relationship with chemical composition.


Study area

The study was carried out in the tropical zone of southeastern Mexico (17°58'20" North Latitude and 92°35'20" West Longitude, at an average altitude of 0 meters; mean annual temperature of 27°C and mean annual precipitation of 2550 mm. The experiment was carried out in the facilities of the production area and rabbits studies of the Academic Division of Agricultural Sciences of the Universidad Autónoma Juárez de Tabasco, Mexico.

Animals and experimental procedures

Twenty-four male New Zealand rabbits of eight weeks of age and 1±0.25 kg live weight were used, they were housed individually in cages of 60 x 40 x 80 cm, equipped with an automatic plastic feeder and waterer; an adaptation period of 7 days and an evaluation period of 15 days were carried out according to Somers et al, (2008). Forage of guasimo (Guazuma ulmifolia), cocohite (Gliricidia sepium), bahiagrass (Paspalum notatum), Egypt grass (Brachiaria mutica) and humidicola grass (Brachiaria humidicola) was evaluated. The animals received 40 g of commercial feed daily to cover the digestible energy requirement for maintenance reported by Xiccato and Trocino (2010) (102.77 kcal/kg live weight0.75). The forages evaluated were offered daily and simultaneously, 50 g of each fresh forage, suspended from the cage ceiling by elastic bands; once 85 % of the offered forage was consumed, 10 g were added to ensure availability.

Chemical analysis and variables studied

Proximal chemical analysis was performed on samples of commercial feed and forages (Table 1). For dry matter (DM) determination, the samples were processed in a forced air oven at 50-60 °C for 48 h. An aliquot of these samples was taken from the commercial feed and forages (Table 1). An aliquot of these samples was placed in an oven at 110 °C to determine total moisture, and subsequently crushed to pass a 1 mm sieve using a Wiley mill (Model 4; Arthur H. Thomas Co. Philadelphia, Pa., USA). Crude protein (CP) (method 954.05) was determined by the macro-Kjeldahl procedure (N x 6.25) (AOAC 1990). Acid detergent fiber (ADF) and neutral detergent fiber (NDF) were determined according to Van Soest (1963) and Van Soest et al. (1991).

Table 1 Proximate chemical analysis of commercial feed and tropical forages offered to fattening rabbits 

Variables (%) Commercial feed Guasimo (Guazuma ulmifolia) Cocohite (Gliricidia sepium) Swirl Grass (Paspalum notatum) Humidicola Grass (Brachiaria humidicola) Egypt Grass (Brachiaria mutica)
Dry matter 87.73 32.44 94.50 24.70 74.00 92.90
Crude protein 20.59 17.70 15.84 14.20 9.00 11.65
Acid detergent fiber 38.95 22.72 32.12 37.00 40.80 48.55
Neutral detergent fiber 21.89 37.61 41.74 66.90 67.70 70.45

The variables studied were fresh consumption, dry matter consumption and consumption of CP, ADF and NDF fractions; in addition, the relative preference index (RPI) was estimated according to Ben Salem et al, (1994) using commercial feed as reference material. The parameters were defined as follows: feed intake on day 1 (FI1), average commercial feed intake for the first 5-day period (FI5), average commercial feed intake for the second 5-day period (FI10), average commercial feed intake for the third 5-day period, forage intake on day 1 (I1), average forage intake during the first 5 days (I5), average forage intake for the second 5-day period (I10), average forage intake for the third 5-day period (I15), amount of feed offered on day 1 (OF1), average amount of feed offered in the first 5-day period (OF5), average amount of feed offered in the second 5-day period (OF10), average amount of feed offered in the third 5-day period (OF15), amount of forage offered on day 1 (D1), amount of forage offered in the first 5 days (D5), amount of forage offered in the second 5-day period (D10) and amount of forage offered in the third 5-day period (D15).

Calculation and statistical analysis

The results obtained were analyzed by descriptive statistics and analysis of variance (ANOVA) completely at random; Pearson's correlation was also used to examine the association between chemical composition and total forage consumption using the STATGRAPHICS 5.1 statistical program. The relative preference index was determined from the ratio for day 1, RPI1 = ((I1/D1)/(FI1/OF1)); for the first 5-day period, RPI2= ((I5/D5)/(FI5/OF5)), for the second 5-day period, RPI3 =((I10/D10)/(FI10/OF10)) and for the third 5-day period, RPI4= ((I15/D15)/(FI15/OF/15)).


Table 1 shows that the highest CP content in forages corresponded to Guazuma ulmifolia (17.70%), followed by Gliricidia sepium (15.84%); the lowest CP content was found in Brachiaria humidicola (9.00%). Regarding fibrous content, the genus Brachiaria presented the highest values of ADF (40.80-48.55%), Guazuma ulmifolia had the lowest value of ADF with 22.72%; also, the FDN content was higher in the genus Brachiaria forages (67.7- 70.45%); the forages Guazuma ulmifolia and Gliricidia sepium obtained values of 37.61% and 41.74%, respectively.

Table 2 shows that Gliricidia sepium was the species with the highest intake with 51 g (p<0.05) per day, followed by commercial feed (37 g) and Brachiaria mutica (36 g); the lowest intake was observed with Guazuma ulmifolia and Paspalum notatum. Likewise, Gliricidia sepium showed a higher total DM intake of 16.5 kg and total crude protein intake of 2.7 kg (p <0.05). Brachiaria mutica was the second highest total DM intake 11.20 kg. With respect to NDF and ADF intake, Brachiaria mutica showed the highest total intake with 8.49 kg and 5.85 kg, respectively (p <0.05), compared to the other species evaluated.

Table 2 Consumption of tropical forages, dry matter, crude protein, ADF and NDF in fattening rabbits 

Variable Commerci al feed Guasim(Guazuma ulmifolia) Cocohite (Gliricidia sepium) Swirl grass (Paspalum notatum) Humidicola grass (Brachiaria humidicola) Egypt grass(Brachiaria mutica)
Total consumption Kg (14 days) 12.42b 7.65c 17.09ª 7.47c 7.70c 12.06b
Average consumption per animal Kg (14 days) 0.564b 0.34c 0.777a 0.34c 0.350c 0.548b
Average daily consumption g 37b 23c 51a 14c 23c 36b
Total DM consumption Kg 10.89b 2.48C 16.15a 1.84C 5.70c 11.20b
Total CP consumption Kg 2.56a 1.35c 2.70a 1.06c 0.69c 1.40b
Total ADF consumption Kg 4.83b 1.73d 5.49a 2.76c 3.14c 5.85ª
Total NDF consumption Kg 2.71c 2.87d 7.13a 4.99d 5.21b 8.49a

a, b, c Different letters in the same column P<0.05

Table 3 shows that the correlation coefficient between total forage intake and CP, NDF and ADF content is low (P> 0.05); therefore, there is no relationship between the elements.

Table 3 Pearson's correlation coefficient between total intake, I1, I5, I10, I15 and Crude Protein, Neutral Detergent Fiber and Acid Detergent Fiber content of tropical forages fed to fattening rabbits 

Element Correlation coefficient r2 P Value
Total consumption Crude protein 0.12 3.74 0.7552
Neutral detergent fiber 0.33 10.04 0.6034
Acid detergent fiber 0.03 0.89 0.8798
Consumption on day 1 (I1) Crude protein -0.374 13.99 0.5351
Neutral detergent fiber 0.4466 21.71 0.4289
Acid detergent fiber 0.0676 0.4577 0.9139
Consumption of the first 5-day period (I5) Crude protein -0.1966 3.868 0.7512
Neutral detergent fiber 0.2347 5.5108 0.7039
Acid detergent fiber -0.1509 2.2796 0.8085
Consumption of the second 5-day period (I10) Crude protein 0.1052 1.1075 0.8663
Neutral detergent fiber -0.1222 1.4947 0.8447
Acid detergent fiber -0.4282 18.336 0.4719
Consumption of the third 5-day period (I15) Crude protein -0.0164 0.0269 0.9791
Neutral detergent fiber 0.0464 0.2154 0.9409
Acid detergent fiber -0.2979 8.8761 0.6264

With respect to the relative preference index, Table 4 shows that Gliricidia sepium had the highest consumption preference (P<0.05), while Brachiaria mutica, Brachiaria humidicola, Paspalum notatum and Guazuma ulmifolia forages did not show significant variations (P>0.05) in consumption preference during the experimental period.

Table 4 Relative consumption preference index of Gliricidia sepium, Brachiaria mutica, Brachiaria humidicola, Paspalum notatum and Guazuma Ulmifolia in fattening rabbits 

Consumption (DM kg day-1) Consumption (% offered)
Forage I1 I5 I10 I15 I1/D1 I5/D5 I10/D10 I15/D15
Cocohite (Gliricidia. Sepium) 27.43 29.21 35.11 35.11 0.55a 0.79a 0.95a 0.95a
Egypt grass (Brachiaria Mutica) 23.41 18.23 9.20 13.71 0.47b 0.79b 0.25b 0.37b
Humidcola grass (Brachiaria Humidicola) 20.04 18.53 15.51 16.85 0.40b 0.50b 0.42b 0.46b
Swirl grass (paspalum notatum) 6.23 5.78 5.42 5.77 0.12c 0.16c 0.15c 0.16c
Guasimo (Guazuma Ulmifolia) 7.29 7.97 7.45 6.22 0.15c 0.22c 0.20c 0.17c
Forage RPI1 Rank RPI 2 Rank RPI 3 Rank RPI 4 Rank
Cocohite (Gliricidia. Sepium) 0.59 1 0.85 1 1.03 1 1.03 1
Egypt grass (Brachiaria Mutica) 0.51 2 0.53 3 0.27 3 0.40 3
Humidcola grass Brachiaria Humidicola.) 0.43 3 0.54 2 0.45 2 0.50 2
Swirl grass (paspalum notatum) 0.13 5 0.17 5 0.16 5 0.17 5
Guasimo (Guazuma Ulmifolia) 0.16 4 0.23 4 0.21 4 0.18 4

RPI1= (I1/D1)/(FI1/OF1).; RPI 2 = ((I5/D5)/(FI5/OF5); RPI 3 = (I10/D10)/(FI10/OF10); RPI4=(I15/D15)/(FI15/OF/15)

a, b, c Different letters in the same column P<0.05


In the present study, the simultaneous forage offering method and the relative preference index were used to measure consumption preference. Gliricidia sepium tree forage had higher consumption and preference compared to Brachiaria mutica grass, Guazuma ulmifolia tree, and Paspalum notatum and Brachiaria humidicola grasses (P <0.05). (Kontsiotis et al, 2015), as well as (Clauss & Hatt, 2017), mention that the diet composition of wild rabbits is composed of different plants and food types (grasses, shrubs, herbs and leaves), depending largely on the availability and quality of food resources in the environment. According to the results of (DeJaco & Batzli, 2013), cottontail rabbits (Sylvilagus floridanus) prefer in their diet herbaceous plants such as: Trifolium pratense, Medicago sativa, Persicaria vulgaris, Aster ericoides and Viola pranticola; as well as woody plants, which it may preferentially consume depending on their availability. (Ozakwe & Ekwe, 2017) indicate that preference measured through forage consumption (palatability) in rabbits, is a phenomenon influenced by dietary and environmental factors. However, (Bobadilla et al, 2020) points out that the trophic selection of rabbits is positive for grasses, while forages and shrubs are avoided; however in these animals the consumption of more nutritious plants (rich in protein) can be of great importance in ecosystems where the available plants have low nutritional value. In this sense, it has been shown that the consumption of woody species by rabbits increases when the availability of grasses decreases, due to seasonal variations.

Regarding the relationship between consumption and chemical composition of diets, according to (Franz et al, 2011) and (Somers et al, 2008) rabbits are selective consumers, so they prefer parts with high protein content, since in nature the consumption of protein- rich materials guarantees a higher nutritional value of a low-energy diet. For their part (Crowell et al, 2018), points out that in the wild, pygmy rabbits (Brachylagus idahoensis) and cottontail rabbits (Sylvilagus nuttallii) employ behavioral strategies to consume materials with specific characteristics, such as low or high amount of fiber according to the availability in the meadow, or with higher crude protein content to decrease exposure times to predators and obtain food of higher nutritional quality; or to regulate or decrease the amount of secondary metabolites present in the plants they consume. According to (Wallage Drees & Deinum, 1985), the nutritional composition of the diet of wild rabbits represents crude fiber (CF) levels of 25 to 30% (DM) and neutral detergent fiber (NDF) levels of 50 to 60%. (Ogbuewu et al, 2017) (Ozakwe & Ekwe, 2017) indicate that there is a relationship between crude protein content and the preference of rabbits in consumption terms. The authors found that forages with high crude protein content such as Centrosema pubescence, Calopogonium mucunoides and Elaeis guinensis were the most consumed in a cafeteria trial. (Lush et al, 2017) report that rabbits prefer short grasses with lower fiber concentration and select forages for higher quality rather than higher quantity to meet their nutritional needs. However (Safwat et al, 2014) and (Abubakar et al, 2015) reported a large variability in the response of rabbits to forage supplementation; besides, (Kontsiotis et al, 2015) and (Lush et al, 2017), note that changes in feeding strategies are likely an adaptation to seasonal changes imposed by environmental conditions, which affect both forage availability and quality and that the diet of herbivorous mammals such as rabbits, can be affected by a myriad of factors such as resource availability, forage quality, area available for foraging and the presence of predators. (Lush et al, 2017) note that lagomorphs such as rabbits and hares are selective consumers, capable of consuming large amounts of low quality food and adapting to the availability of resources with higher nutritional quality.

In the present study, the content of crude protein, acid detergent fiber and neutral detergent fiber in the forages studied (crude protein, ADF and NDF) did not affect the preference in terms of consumption in any of the consumption periods evaluated (I1, I5, I10, I15) (P> 0. 05); which is contrary to that reported by (Ulappa et al, 2014), who point out that the odds of a forage being consumed increase 1.64 times for every 1% increase in crude protein content. According to (Somers et al, 2008), the selection of higher nutritional quality diets is a behavioral adaptation by which herbivores maximize their nutrient intake by selecting plants with high crude protein content. (Schmalz et al, 2014) reports that pygmy rabbits (Brachilagus Idahoensis) prefer to feed on sagebrush (Artemisa vulgaris); which has higher crude protein and lower fiber content (ADF-NDF); such preference may be associated more with the energy density it presents, being richer in protein than fiber, which may be especially important during winter when pygmy rabbit diets are 99.1% sagebrush, because energy requirements are especially high for thermoregulation at low temperatures, which could be contrary in tropical areas where temperatures are high. On the other hand (Hernández et al, 2017) and (Carpio et al, 2017) point out that the differences observed in consumption preference in rabbits, may be related to the presence of secondary metabolites such as saponins, flavonoids, total phenolic compounds and tannins, in cover crops and some fruits, which were not quantified in the foods studied in the present work. (Malavé et al, 2013) and (Ogbuewu et al, 2017) point out that the study and use of resources with high protein content in tropical areas, represent a viable option for rabbit feeding without relying on commercial feeds.


The CP, NDF and ADF content of tropical forages did not modify the consumption preference in fattening rabbits. Gliricidia sepium forage was preferred by fattening rabbits compared to Brachiaria mutica, Guazuma ulmifolia, Paspalum notatum and Brachiaria humicola forages. The study of forage preference in rabbits and its relationship with nutrient content is necessary to improve the use of these resources in tropical areas.


Abubakar M, Ibrahim U, Yusuf AU, Muhammad AS, Adamu N. 2015. Growth performance, carcass and organ characteristics of growing rabbits fed graded levels of Moringa oleifera leaf meal in diets. Bayero Journal of Pure and Applied Sciences. 8: 7-9. ISSN: 2006-6996. [ Links ]

AOAC (1990) Official Methods of Analysis. Association of Official Analysis Chemists. EUA. [ Links ]

Ben Salem H, Nefzaoui A, Abdouli H. 1994. Palatability of shrubs and fodder trees measured on sheep and dromedaries: 1. Methodological approach. Animal Feed Science and Technology. 46: 143-153. ISSN: 0377-8401. [ Links ]

Bobadilla SY, Marchetta A, Dacar MA, Ojeda RA, Cuevas MF. 2020. Food habits of European rabbit and its role as seed dispersal of two Mosqueta roses: Facilitation among non-native species in a semiarid protected area of Argentina. Biological Invasions. 22: 1565-1571. ISSN: 1387-3547. [ Links ]

Clauss M, Hatt JM. 2017. Evidence-based rabbit housing and nutrition. Veterinary clinics: exotic animal practice. 20: 871-884. ISSN: 1094-9194. [ Links ]

Carpio JA, Soriano MA, Guerrero - Casado J, Prada LM, Tortosa FS, Lora A, Gómez JA. 2017. Evaluation of an unpalatable species (Anthemis arvensis L.) as an alternative cover crop in olive groves under high grazing pressure by rabbits. Agriculture, ecosystems and environment. 246:48-54. ISSN: 0167-8809. [ Links ]

Crowell MM, Shipley LA, Forbey JS, Rachlow JL, Kelsey RG. 2018. Dietary partitioning of toxic leaves and fibrous stems differs between sympatric specialist and generalist mammalian herbivores. Journal of mammalogy. 99(3): 565-577. ISSN 0022-2372 [ Links ]

Dejaco CE, Batzli GO. 2013. Palatability to small mammals in nonnative grasslands of eas-central Illinonis. Journal of mammalogy. 94 (2): 427-435. ISSN 0022-2372. [ Links ]

Franz R, Kreuzer M, Hummel J, Hatt J M, Clauss M. 2011. Intake, selection, digesta retention, digestion and gut fill of two coprophageous species, rabbits (Oryctolagus cuniculus) and guinea pigs (Cavia porcellus), on a hay‐only diet. Journal of animal physiology and animal nutrition. 95: 564-570. Online ISSN: 1439-0396. [ Links ]

Hafsa S A, Salem A Z M, Hassan A A, Kholif A E, Elghandour M M Y, Barbabosa A, López S. 2016. Digestion, growth performance and caecal fermentation in growing rabbits fed diets containing foliage of browse trees. World Rabbit Science. 24: 283-293. ISSN: 1257-5011. [ Links ]

Hernández-hernández E, López - Ortiz S, Villaruel-Fuentes M, Pérez-Hernández P., Velasco-Velasco J, Salinas Ruíz J. 2017. Feeding rabbits (Oryctolagus cuniculus) with tree fruits from tropical deciduous forest. World Rabbit Science. 25: 135 - 145. ISSN: 1257-5011. [ Links ]

Kontsiotis VJ, Bakaloudis DE, Merou T, Xofis P. 2015. Trophic ecology of the European wild rabbit Oryctolagus cuniculus on the mediterranean island of Lemnos, Greece. Ecologycal Research. 30: 683-691. Online ISSN: 1440-1703. [ Links ]

Lush L, Ward AI, Wheeler P. 2017. Dietary niche partitioning between sympatric brown hares and rabbits. Journal of zoology. 303(1): 36-45. Online ISSN: 1469-7998. [ Links ]

Malavé AA, Córdova RL, García RA, Méndez NJ. 2013. Composición bromatológica de la carne de conejos suplementados con mataratón y cachaza de palma aceitera. Revista MVZ Córdoba. 18: 3452-3458. ISSN-L: 0122-0268. [ Links ]

Nieves D, Terán O, Cruz L, Mena M, Gutiérrez F, Ly J. 2011. Digestibilidad de nutrientes en follaje de árnica (Tithonia diversifolia) en conejos de engorde. Tropical and subtropical Agroecosystems. 14: 309-314. E-ISSN: 1870-0462. ]

Ogbuewu IP, Emenalom OO, Okoli IC. 2017. Alternative feedstuffs and their effects on blood chemistry and haematology of rabbits and chickens: a review. Comparative Clinical Pathology. 26: 277-286. Electronic. ISSN: 1618-565X. [ Links ]

Osakwe II, Ekwe OO. 2017. Variation in relative palatability of different forages fed to rabbits. Animal Research International. 4: 608-610. eISSN: 1597-3115. [ Links ]

Prebble JL, Meredith AL. 2014. Food and water intake and selective feeding I rabbits on four feeding regimes. Journal Animal Physiology and Animal Nutrition. 98: 991-1000. Online ISSN: 1439-0396. [ Links ]

Safwat AM, Sarmiento-Franco L, Santos-Ricalde RH, Nieves D. 2014. Determination of tropical forage preferences using two offering methods in rabbits. Asian-Australasian Journal of Animal Science. 27(4):524-529. ISSN: 1011-2367. [ Links ]

Schmalz JM, Wachocki B, Wright M, Zeveloff SI, Skopec MM. 2014. Habitat selection by the pigmy rabbit (Brachylagus Idahoensis) in Northeastern Utah. Western North American Naturalist. 74: 456-466. ISSN: 1527-0904. ]

Somers N, D’Haese B, Bossuyt B, Lens L, Hoffmann M. 2008. Food quality affects diet preference of rabbits: experimental evidence. Belgian Journal of Zoology. 138 (2): 170-176. ISSN: 0777-6276. ]

Ulappa AC, Kelsey RG, Graham GF, Rachlow JL, Shipley LA, Bond L, Pu X, Sorensen FJ. 2014. Plant protein and secondary metabolites influence diet selection in a mammalian specialist herbivore. Journal of mammalogy. 95(4): 834-842. ISSN: 0022-2372. [ Links ]

Van Soest PV. 1963. Use of Detergents in the Analysis of Fibrous Feeds. II. A Rapid Method for the Determination of Fiber and Lignin. Journal of Association of Official Agricultural Chemists. ISSN 1944-7922. 46(5):829 - 835. [ Links ]

Van Soest PV, Robertson JB, Lewis B. 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. Journal of dairy science. 74(10): 3583-3597. ISSN 0022-0302. [ Links ]

Xiccato G, Trocino A. 2010. Energy and protein metabolism and requirements. In: De Blas C, Wiseman J, editors. Nutrition of the rabbit, 2nd edition. London UK, CABI. P. 93 - 118. ISBN-13: 978-1845936693 [ Links ]

Wallage-Drees JM, Deinum B. 1985. Quality of the diet selected by wild rabbits (Oryctolagus cuniculus) in autumn and winter. Netherlands Journal of Zoology. 36(4):438-448. ISSN: 0028-2960. [ Links ]

Code: e2021-25.

Received: May 02, 2021; Accepted: September 06, 2021

Creative Commons License Este es un artículo publicado en acceso abierto bajo una licencia Creative Commons