Understanding ammonia emissions: the impact of feed chemical composition on dairy Holstein farms

The aim of this study was to explore the relationship between the chemical composition of cattle feed and the emission of ammonia. To achieve this, we conducted a thorough chemical analysis of the feed, examining factors such as digestible crude protein, rumen undegradable protein, bacterial production of metabolic protein, and levels of methionine and lysine. Our research focused on how these feed components impact both milk yield and ammonia emissions. The study found that there was a positive correlation between digestible crude protein and milk yield, while rumen undegradable protein had a strong positive correlation with milk yield. Additionally, the study revealed a negative correlation between bacterial production of metabolic protein and daily milk yield. The concentration of methionine was weakly positively associated with milk yield, while lysine had a weak negative association with milk yield. The concentration of lysine in the rations was positively correlated with ammonia emissions, while methionine was negatively correlated with it. The study also found that rumen undegradable protein had a significant negative correlation with ammonia emission. Overall, the study highlights the importance of effective feeding management practices in optimizing animal productivity and minimizing ammonia emissions, to promote sustainable agriculture.