Published in Scientific Papers. Series D. Animal Science, Vol. LV
Written by NASSER MOHAMED EMAD ABD EL-WAHAB
The objectives of this work are to characterise the in vitro fermentation contribution of both soluble and insoluble fractions, and the effects of ensiling of acacia (Acacia saligna, AC) and leucaena (Leucaena leucocephala, LE) leaves with different levels of urea (U, 0, 1, 3 or 5%) on gas production, energy value and organic matter digestibility (OMD%) of AC and LE. The acacia and leucaena were ensiled for 35 days. Ground samples (200 mg DM) of the ensiled materials from the eight treatments were incubated in glass syringes with rumen fluid obtained from fistulated sheep fed berseem hay and commercial concentrate mixture twice a day. Cumulative gas production was recorded at 3, 6, 9, 12, 24, 48, 72 and 96 h of incubation and the kinetics of gas production was described by using the equation: Gas (Y) = a + b (1-exp-ct).Ensiling of AC and LE leaves with U increased crude protein and ash, while the contents of tested samples of total phenol (TP), total tannins (TT) and condensed tannins (CT) were decreased. Also, ensiling of AC and LE leaves with U significantly (P <0.05) decreased gas production. All washed samples showed losses of soluble material. The gas production was, in general, significantly (P<0.05) higher for the unwashed substrates. Leucaena gave the highest values of gas production compared with acacia. The gas production volume was significantly (P <0.05) higher for ensiled AC and LE leaves without U than ensiled AC with 5%U or ensiled LE with 3%U. The maximum rate of gas production increased after ensiling AC and LE leaves with 5% and 3% U, respectively. The calculated values of metabolizable energy (ME) and net energy (NE) were significantly (P<0.05) increased for ensiled AC with 3 and 5%U, while ensiled LE with U was not significantly affected. The organic matter digestibility (OMD %) and microbial protein production were significantly (P<0.05) higher for ensiled AC and LE with U, while short chain fatty acids (SCFA) were significantly (P<0.05) decreased. The concentrations of TP, TT and CT were strongly correlated (p<0.01). The TP, TT and CT were negatively related (p<0.01) with neutral detergent fiber (NDF) and acid detergent fiber (ADF), but not with hemicelluloses (HEMI). The crude protein was strongly correlated (p<0.01) with NDF, ADF and CT and negatively related (p<0.01) with TF and TT, but not with HEMI. In conclusion, there were negative effects on the in vitro gas production occurring more consistently when AC and LE were ensiled with different levels of U, while OMD% and microbial proteins were significantly (P<0.05) increased. The in vitro digestibility and gas production parameters were significantly correlated with chemical composition of shrubs. Finally, it is generally more appropriate to measure the degradation of organic matter as usual dry matter can give problems of interpretation of the significance of the soluble fraction.
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{tag}meta name="citation_title" content="Contribution of both soluble and insoluble fractions of untreated and treated Acacia saligna and Leucaena leucocephala with different levels of urea to rumen fermentation, in vitro"{/tag} {tag}meta name="citation_journal_title" content="Scientific Papers. Series D. Animal Science"{/tag} {tag}meta name="citation_publication_date" content="2012"{/tag} {tag}meta name="citation_author" content="NASSER MOHAMED EMAD ABD EL-WAHAB" {/tag}
Acacia saligna
