The Use of Clay as a Methane Emission Mitigating Feed Additive in Djallonké Rams

Abstract

Four groups each composed of six rams with 15 kg average body weight were submitted to one of the following diet: Panicum maximum C1 (PM), Panicum maximum C1 plus concentrate (PM_Co), Panicum m. C1 plus clay (PM_Ar ) and Panicum maximum C1 plus concentrate plus clay (PM_Co_Ar). The concentrate is composed of 90% weat bran, 9.25% cottonseed cake, 0.5% premix and 0.25 cooking salt. The clay used was a mixture of 59% smectite, 14% kaolinite and 27% quartz. The significance of treatments on variation in physico-chemical characteristics (ruminal pH and concentration of ammonia nitrogen), as well as in the rumen fermentation profile i.e . Volatile Fatty Acid concentration and in the enteric methane (CH 4 ) production, depending on the rumen fluid collection time (at 9 o’clock and 13 o’clock), were studied using AOV. The highest ruminal pH was recorded in animals fed the mixture of Panicum plus clay, which is 7.02 ± 0.12 against 6.96 ± 0.12, 6.8 ± 0.06 and 6.69 ± 0.15, respectively in animals fed with PM, PM_Co and PM_Co_Ar. Incorporation of clay in the mixture of Panicum C1 plus concentrate had a stabilizing effect on ruminal pH. A significant decrease in the concentration of ruminal N-NH3 was recorded with PM_Ar (56.6 ± 15.2 g/ml), compared to PM (89.0 ± 18.9 g/ml). However, the ruminal N-NH 3 concentration of animals fed the PM_Co diet (71.0 ± 15.1g /ml) increased in comparison to that of the PM_Co_Ar diet fed animals. Compared to the enteric methane concentration of the PM ration fed animals, the decrease of CH4 concentration was 2% - 5%, 7% - 11% and 19% - 23% respectively in the PM_Ar, the PM_Co and the PM_Co_Ar diets fed rams. These results suggest that the methane reducing effect of clay might be emphasized by the concentrate supplementation of the diet.