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 (CH4) 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-NH3 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.