Abstract

An in vitro study was undertaken to explore the impact of individual vs. combined supplementation of tannin and saponin containing phyto-sources on total gas and methane production, feed fermentation and rumen protozoa. These phyto-sources constituted individually or in combination represented the supplementation level equivalent to 17% of concentrate or 5.1% of total diet. In this study, control treatment (T₀) was formulated without any supplementation of tannin or saponin source. Among the treatments, lowest methane production was recorded in treatment T₁ (3.91 ml/200 mg DM). Combined supplementation of tamarind seed husk and soapnut (T₃ and T₇) in this study exhibited lower methane production as compared to control (T₀). On the contrary, other treatments either with individual supplementation of soap nut (T₂) or combined supplementation (T₄, T₅ and T₆) have not shown any decrease in methane production with reference to control. In general, the magnitude of methane reduction was comparatively higher in the treatments where tamarind seed husk was supplemented individually (T₁, 29.8%) or in higher proportion in combined preparation with soapnut (T₃, 19.4%). A decrease of 2.5 units in dry matter digestibility irrespective of the treatments was recorded due to the supplementation. A significant reduction in rumen protozoa (x10⁵/ml) was recorded in all the test treatments and the intensity of reduction was comparatively more with individual or combined preparation where soapnut made the larger proportion. Results indicated that the reduction in protozoa always not accompany with a concurrent decrease in methane production.

Keywords: Environment; Methane; Mitigation; Soapnut; Tamarind seed husk