NUTRITIONAL COMPOSITION, IN VITRO DEGRADATION AND POTENTIAL FERMENTATION OF TREE SPECIES GRAZED BY RUMINANTS IN SECONDARY VEGETATION (ACAHUAL) OF DECIDUOUS FOREST
S. Albores-Moreno1, J. A. Alayón-Gamboa1*, L. A. Miranda-Romero2, G. Jiménez-Ferrer1, J. C. Ku-Vera3, L. Vargas-Villamil4
1Southern Frontier College (ECOSUR), Avenida Rancho, Polígono 2-A, Ciudad Industrial, Zip 24500, Lerma, Campeche, México
2Graduate Department of Animal Production, Autonomous University of Chapingo, Chapingo, México
3Department of Veterinary Medicine and Animal Science, Autonomous University of Yucatan, Yucatán, México
4 Department Animal Production, Postgraduate College Campus Tabasco, Tabasco, México
*Corresponding author E-mail address: email@example.com
Study conducted to know the nutritional composition, in vitro degradation and the potential fermentation of tree leaves species grazed by ruminants in secondary vegetation of a deciduous forest. Tree leaves were selected from 18 tree species that were subjected to in vitro fermentation. Fermentation variables were analyzed with a designed block repeated over time. The content of CP, NDF and ADF fluctuated among species, from 109 to 262, 391 to 641 and 322 to 579 g kg-1of DM, respectively. The concentrations of condensed tannins (CT) presented a wide variation among species and ranged from 1.73 to 233.45 g kg-1 DM. The significant differences (P <0.05) observed among species in fermentation and digestibility. G. floribundum, M. lindeniana, V. gaumeri, H. barvensis, T. amygdalifolia and C. gaumeri had the highest gas volume (155 to 293.88 mL g-1), total fermentation (379.45 to 677.39 mg g-1), fermentation rate (0.031 to 0.038 h-1), and soluble fraction (178.3 to 265 g kg of DM-1). In addition, they had highest values of the rapid fermentation fractions (123.58 a 214.88 mg g-1), medium fermentation (37.07 to 217.87 mg g-1), and slow fermentation fractions (162.33 to 244.64 mg g-1), and the highest IVDMD values (39.71 to 54.93%) and IVOMD (47.96 to 66.50%). The species H. albicans, P. piscipula, B. divaricata, L. rugosus, N. emarginata and M. bahamensis had the lowest potential fermented gas emission index (181.13, 181.19, 200.59, 206.36 and 217.24 mL g-1MOD). It is concluded that the species G. floribundum,M. lindeniana, V. gaumeri, H. barvensis, T. amygdalifolia and C. gaumeri present in the secondary vegetation of the forest have a good potential in the feeding of ruminants due to their highest fermentability in the rumen.
Key words: IVOMD, fermentation kinetics, tree leaves, secondary metabolites.