Mineral Concentrations and Rumen Degradability of Biodegraded &amp;lt;i&amp;gt;Enterolobium cyclocarpum&amp;lt;/i&amp;gt; (Jacq) and &amp;lt;i&amp;gt;Pterocarpus santalinoides&amp;lt;/i&amp;gt; (L’Her) with &amp;lt;i&amp;gt;Aspergillus niger&amp;lt;/i&amp;gt;

A A Ayuk,J O Ayuk,B I Okon,E A Iyayi

doi:10.4236/as.2014.512118

Abstract

The effects of solid state fermentation on the mineral concentrations and in sacco degradation characteristics of dry matter in two multipurpose tree leaves was investigated. Biodegraded Enterolobium cyclocarpum (EC) and Pterocarpus santalinoides (PS) leaves were previously inoculated with Aspergillus niger and incubated at 30&degC for five incubation periods (0, 7, 14, 21 and 28 days). After each incubation period, samples were oven dried at 60&degC, allowed to cool and ground for mineral analysis and in sacco dry matter degradability. Three fistulated West African Dwarf (WAD) rams (Ovis aries) were then used for the dry matter degradability. Five grams of each sample was emptied into nylon bag (Polymon, Switzeland) with pore size of 4 μ and effective size of 5 cm × 18 cm and incubated in the rumen of the fistulated animals for 6, 12, 24, 48, 72, and 96 h. The results showed that the mineral contents of biodegraded EC samples were affected by incubation period. Mean values of Ca, Cu, K, Na, and Zn were significantly increased (0.05), while mean values of Fe, Mg, and Mn were first reduced before significantly increasing (0.05). However, the composition of P showed significant reduction (0.05) up to day 28 where no change was observed. Mineral concentrations in biodegraded PS were also affected by incubation periods. Values of Ca, Fe, K, Mg, Mn, Na, and Zn were significantly increased (0.05). However values of Cu, and Fe only increased after day 14, while the value of P was reduced significantly over the different incubation periods. Potential degradability (PD) for biodegraded EC was highest at day 0 (50.79%) but not significantly different from potential degradability of longer incubation periods to day 28 (48.68%). PS had higher PD than EC. In spite of high PD values, PS comparatively degraded faster than EC. Effective degradability (ED) for EC was highest for day28 (36.71%) and not significantly different from days 21 (34.83%) and 7 (35.29%) but significantly different from days 0 (31.32%) and 14 (31.75%) respectively. However, the ED for PS was highest for day 0 (31.39) samples and significantly differed from other incubation periods, further increase in period only showed lower but similar ED values for days 7 (27.52%), 14 (26.76%), 21 (27.42%) and 28 (26.86%) respectively. In this study, the continued reduction in P concentrations in both biodegraded EC and PS suggest that Aspergillus niger has preferential demand for P and in sacco degradation showed increase in PD and ED values for fungal biodegraded EC and reduction in PS, suggesting improved quality of EC.

Highlights

Ruminant production in the tropics is hampered by scarcity of protein and energy rich feedstuffs especially in the dry season
This is so because tropical forages are generally of low quality and their intake by animals is usually limited by high levels of fibre and low nutrient content, protein which is essential for both animal and rumen microbial growth [1]
Small-holder farmers of Sub-Saharan African countries [6] are increasingly relying on various potential multipurpose trees (MPTs) that can provide a green feed throughout the year which may be useful as feed supplements to the typical low-quality diets [7]

Summary

Introduction

Ruminant production in the tropics is hampered by scarcity of protein and energy rich feedstuffs especially in the dry season. MPTs contain high levels of crude protein and minerals and many show high levels of digestibility [3] and are potential sources of cheap feed for ruminant animals, especially during dry seasons [4]. They maintain higher protein and mineral contents during growth than do grasses, which decline rapidly in quality with progress to maturity [5]. The effects of solid state fermentation on the mineral profile and in sacco degradation characteristics of dry matter in Enterolobium cyclocarpum (EC) and Pterocarpus santalinoides (PS) were evaluated

Location and Forage

Results and Discussion

Rumen Degradation

Conclusion