Combined Effects of Cottonseed Oil and Tannin from Tea By-Products (Camellia sinensis) Supplementation on Nutrient Digestibility, Performance and Enteric Methane Production of Fattening Cattle

The combined effect of cottonseed oil and tannin from tea by-products (Camellia sinensis) supplementation on feed intake, digestibility, growth performance and enteric methane production was studied using twenty-four fattening crossbred cattle (Brahman x Laisind) in a completely randomized block design (CRBD) experiment with six replications in each. All animals were fed a basal diet consisting of ensiled maize stover, elephant grass; concentrate; corn mill and cassava pulp. The treatments were four supplements of 1.5% oil plus 0.3% tannins (O1.5T0.3), 1.5% oil plus 0.5% tannins (O1.5T0.5), 3.0% oil plus 0.3% tannins (O3.0T0.3) và 3.0% oil plus 0.5% tannins (O3.0T0.5) (%DM intake). The results showed that the supplement of cottonseed oil and tea by-products containing tannins, respectively at 1.5% oil and 0.5% tannins provided higher nutrient digestibility, increased CP intake and daily gain, reducer FCR comparing to these other groups. This combination at these levels also reduced from 4.8 to 12.1% methane emission intensity (CH4 /kg LWG) of fattening cattle. It is likely that supplementation of cottonseed oil combined with tannin from tea by-products increased available energy to cattle in the fattening period, thus increasing weight gain and methane reduction. The lowest enteric methane production (CH4 /kg LWG) found in the group fed 1.5% cottonseed oil combined with 0.5% tannins from tea by-products.