Comparative Rumen Degradability of Some Legume Forages between Wet and Dry Season in West Sumatra, Indonesia

Abstract

An experiment was conducted to evaluate the potential nutritive value of five legume forages (leaves and twigs) in West Sumatra during wet and dry seasons. The chemical composition, in vitro dry matter (IVDMD), organic matter (IVOMD) and crude protein digestibility (IVCPD), in vitro gas characteristics and estimated metabolizable energy (ME) showed variation among legume forages and between different seasons. Crude protein (CP) ranged from 14.2 to 27.8% DM in the wet season, with a significant (p<0.05) reduction in dry season. C. pubescens, G. maculata, L. leucocephala and P. phaseloides showed the least reduction in CP content. The NDF, ADF and lignin were about 39.0, 26.5 and 6.1% DM, respectively in the wet season, and significantly (p<0.05) increased in the dry season, except for NDF of C. mucunoides and C. pubescens. For IVDMD, IVOMD and IVCPD significantly increased in the wet season, but values remained as high as over 50.0% of DM. The in vitro gas characteristics and metabolizable energy were significantly (p<0.05) higher in wet season than the dry season. During both seasons, the rate of constant (c) for G. maculata and ME content for C. pubescens and P. phaseloides were not significantly (p<0.05). Results demonstrated that P. phaseloides and L. leucocephala have a good nutritive value during both wet and dry seasons. Further studies on feeding trials are needed to quantify the animal responses when offered these legume forages.

Nutritive value of selected grasses in North Sumatra, Indonesia

“…Such seasonal changes in the chemical compositions of grasses in tropical climates are a result of the maturity and age of the grass species with the progression of seasons from the dry to rainy season. The lower CP content in the dry season was in agreement with the results reported by Aregheore (2002) and Evitayani et al . (2004a).…”

“…In both of the seasons, the highest ME content was prominent for P. purpureum and C. plectostachyus . The ME content of grasses in the present study was relatively higher than the ME content of several legumes in North Sumatra, varying from 6.4 to 7.8 MJ/kg in the dry season and from 6.9 to 7.8 MJ/kg in the wet season (Evitayani et al . 2004a).…”

“…A previous study has showed that the nutritive value of legumes assessed by nutrient digestibility and metabolizable energy (ME) content varied greatly among species and it was higher in the rainy season than in the dry season (Evitayani et al . 2004a).…”

Impact of season of harvest on in vitro gas production and dry matter degradability of Acacia saligna leaves with inoculum from three ruminant species

“…In the current study, large differences in the nutritive value of Acacia leaves (as assessed by gas production and DM degradability) were observed, which were primarily the result of changes in maturity. Reduction (P<0.01) in the CP content of ASL in summer versus other seasons, is consistent with other studies, as was the observation that the minimum CP content of fodder tree leaves in the dry season was more than twice that of grasses in the wet season (Skarpe and Bergstrom, 1986;Evitayani et al, 2004). However, the CP content of ASL remained relatively high (143 g/kg DM) in the dry season, suggesting the possibility that Acacia sp.…”

“…Our observations are similar to Evitayani et al (2004), who found that IVGP and IVDMD of some legume species increased in the wet season (winter) compared with the dry season (summer). The effect of season on gas production for cattle and sheep, and in DM degradability for all species could be due to effects of CT on available N in leaves which, in summer, had a highly negative effect resulting in low rumen ammonia concentrations (Bonsi et al, 1995), which then reduced microbial growth.…”