The effect of additional nitrate and sulfur in the diet on the methane production in cattle
A growing population together with a change in food habits to a more diverse diet containing more animal products such as meat and milk makes the possibility to produce and sell products of cattle a growing market. And at the same time there is an ongoing debate about global warming, where raising cattle is questioned due to their high production of enteric methane. To be able to raise animals in a more environmental friendly way and at the same time improve productivity in a developing country such as Vietnam would be favorable. The use of feed additives with high electron affinity could decrease the methane production and at the same time improve the gross energy digested. Nitrate and Sulfur are both good electron acceptors, but due to its toxic effects the use of nitrate in feed has been neglected. Recently scientists have recorded that animals adapted to high amounts of nitrate can overcome these toxic effects. This present study used 4 male Yellow cattle which were fed a basal diet added with either of Urea, Urea + Sulfur, Nitrate or Nitrate + Sulfur in a Latin square design. There was a significant lower ratio of CH4/CO2 with the treatment of Nitrate + Sulfur compared with the treatment of Urea which indicate a lower eneric methane production. The study also showed a significantly lower feed intake of the treatments Nitrate, Urea + Sulfur and Nitrate + Sulfur compared with the Urea treatment. Due to a low animal number the study can only be seen as a pilot study. Furthermore, it could also be discussed if the use of nitrate is likely to be used of small-scale farmers due to the high risk of poisoning if used inaccurate.