Effects of biochar in lactating dairy cows diet

Summary in the original language of the document

The feeding of biochar (BC) in livestock as a carbon dioxide sink or carbon storage is controversially discussed. BC has been suggested to improve animal health and performance and reduce enteric methane emissions. However, there is a lack of reliable data for its methane mitigating effect. Therefore, in the present study we investigated the addition of BC to a balanced ration of lactating dairy cows. For the study eight lactating Holstein dairy cows received a basal ration with and without 1% BC on a dry matter basis and were fed over two 36-day periods in a crossover design the respective diet. During the last week of each period, the cows were kept in tie stalls where milk yield and quality, feed intake and nutrient digestibility were quantified. Additionally, the animals were kept for the last two days of the feeding period in respiration chambers for gas emission measurements. The results showed that BC feeding had no significant effect on milk yield, nutrient digestibility and enteric methane emissions compared to the control diet without the addition of BC. Furthermore, feed intake was not affected by the addition of BC and no health problems of the animals in response to the treatment were observed. The results indicate that BC is not an effective feed additive for methane mitigation in dairy cows. However, the beneficial effects of feeding BC to animals suffering from health problems cannot be excluded.