In vitro and ruminal characteristics of the three selected Nigerian herbs: Phyllantus amarus, Ocimum gratissimum and Lactuca taraxacifolia as feed additives in ruminant production

Özet

The study was conducted to evaluate the effects of herbal feed additives on the in vitro and ruminal fermentation by West African dwarf goats. A total of 20 goats were subjected to five dietary treatments for a 12- week feeding study in a completely randomized design: Feed only (control) (T1), Feed + Ocimun gratissimum leaf meal (T2), Feed + Phyllantus amarus leaf meal (T3), Feed + Lactuca taraxacifolia leaf meal (T4), Feed + P. amarus + O. gratissimum + L. taraxacifolia leaf meal (T5). Phytochemical Screening of the three herbs were carried out. Herbs were added at 3g/kg feed and were given at 5% body weight of the animal. The feed samples were subjected to 24 hours incubation. Gas volume were measured at the interval of 3hrs. At the end of incubation, methane volume was estimated. The gas volume produced was used to calculate metabolizable energy (ME), organic matter digestibility (OMD) and short chain fatty acid (SCFA) concentrations. At the end of the feeding trial, rumen liquor was collected to determine ruminal characteristics and the microbial population as may be affected by the medical plants. The results showed that the leaves of the herbs were rich in saponin, tannin and alkaloid. The three medicinal plants were relatively high in crude protein (CP) and moderate in carbohydrate (CHO) content. Treatment containing the mixture of O. gratissimum, P. amarus and L. taxifolia (T5) contained more CP than the rest of the treatments while T2 had the highest CF. There was apparent increase in the value of potential gas production as the incubation period increases in in-vitro study. T1 and T4 produced more gas than the rest of the treatments. Methane production was lower in T3 and T5 compared to other treatments. T1 and T4 equally had the highest ME, OMD and SCFA concentrations. However, T3 and T5 improved the ruminal characteristics and microbial population in the rumen as the population was significantly modified. It is therefore concluded that T3 (Phallantus amarus) and the combination of the three herbs (T5) be used as feed additives for mitigating methane emission and improve rumen ecology of the animals for enhanced ruminant productivity.