Degradation characteristics and tannin bioassay of some browse forage from Kenya harvested during the dry season

Abstract

The potential nutritional value of six species of browse forage from Kenya harvested during the dry season were evaluated by chemical composition, in sacco dry matter (DM) degradation and in vitro gas production technique. The effect of tannins on the rumen fermentation of the forage was evaluated using polyethylene glycol (PEG) in an in vitro study. The chemical composition of the species of browse forage differed significantly (P < 0.05). The content of organic matter ranged from 846.7 to 946.5 g/kg DM. The forage had a high crude protein content (155.5-280.9 g/kg DM) and variable content of neutral detergent fiber (NDF, 236.2-682.8 g/kg DM). The content of total extractable tannins was generally low (0.6-38.5 g/kg DM). At 24 h of incubation, the in sacco DM disappearance ranged from 31.2% to 84.2%. The effective DM degradability also ranged from 29.7 to 73.5%. The gas production after 96 h incubation ranged from 17.5 to 44.2 mL/ 200 mg DM. Use of PEG indicated that tannins had an inhibitory effect on rumen microbial fermentation and this is dependant upon the amount and activity of the tannins present. The estimated in vitro organic matter digestibility and metabolizable energy also increased numerically with the PEG addition. The result of this study indicates that such species of browse forage have the potential to be used as feed supplements for ruminants, especially during the dry season.

Effect of supplementing Rhodes grass hay (Chloris gayana) with Berchemia discolor or Zizyphus mucronata on the performance of growing goats in Kenya

“…The CP content ranged from 50.9 g/kg DM in grass hay to 195.5 g/kg DM in B. discolor, while Z. mucronata had a CP content of 169.5 g/kg DM. The CP content of B. discolor and Z. mucronata was comparable with the reported CP content of similar browse forages (Ondiek et al., 1999; Osuga et al., 2006; Wambui et al., 2006). The maize bran used in the experiment was purchased from local commercial millers, who during milling used mechanical de‐hullers, and therefore, the bran had considerable amounts of the endosperm.…”

“…This may have contributed to the higher CP content of maize bran (156.9 g/kg DM) than that reported by other workers (Ondiek et al., 1999; Wambui et al., 2006). However, the low CP content of the hay was within the range reported (Ondiek et al., 1999; Osuga et al., 2006). The hay had numerically high fibre content (713.1 g/kg DM) than the other feeds used in the experiment.…”

“…Despite the presence of such browse species in the arid and semi‐arid ecosystem of East Africa, there is limited information available on their nutritive value. Previous studies have shown their potential nutritive value for the supplementation of poor‐quality diets consumed by animal (Osuga et al., 2006). The species had good palatability when they were offered with other species such as Acacia mellifera and Maerua angolensis (Osuga et al., 2008).…”

Assessment of Anti-nutritive Activity of Tannins in Tea By-products Based on <i>In vitro</i> Rumen Fermentation

“…The estimated IVOMD and ME content were higher in green by-product than in black tea ( Tables 4 and 5 ), and these values were comparable or higher than several ruminant browse forages containing tannin ( Rubanza et al, 2005 ; Osuga et al, 2006 ; 2007 ). None of the tannin binding agents affected IVOMD and ME content of green tea by-product, but PEG4000, 6000, and 20000 significantly increased IVOMD and ME content of black tea by-products (p<0.05).…”

Microcultures of lactic acid bacteria: characterization and selection of strains, optimization of nutrients and gallic acid concentration

“…Their presence in agro-industrial residues limits their use as animal feed mainly due to antinutritional and toxic effects [15,22]. Some lactic acid bacteria (LAB) are often used as inoculants for silage or as probiotics for ruminants [7,35] and can grow, tolerate or degrade PC.…”