Efeito do aditivo químico a base de ácido propiônico e ácido fórmico em silagens de milho: perfil fermentativo e desempenho de vacas leiteiras

Abstract

Effect of propionic acid and formic acid-based chemical additives on corn silages: fermentative profile and performance of dairy vaccines Organic acids have a great impact on silage fermentation and aerobic stability, acting very effectively against fungi and yeast. The objective of the present study was to evaluate the impact of a chemical additive in the fermentation profile of whole plant corn silage (WPCS) with high dry matter content and the dairy cows' performance fed with re-ensiled WPCS. The study was divided into two trials: Trial 1) The chemical additive Lupro-Mix® NA (35% propionic acid, 21% sodium formate, 20% formic acid, 4% sodium propionate and 20% water) was added in whole plant corn with high dry matter (~40%) and ensiled in experimental silos. The treatments were as follows: (i) without additive (control); (ii) Lupro-Mix® NA (4L per ton of natural matter). A completely randomized design with four replications per treatment was used. The additive was significantly efficient in reducing ethanol content, 1.2 propanediol, ethyl lactate, ethyl acetate, as well as DM losses. There was also a significant increase of propionic acid in relation to the control treatment, thus reflecting in greater aerobic stability of the treated mass. The silage with Lupro-Mix® NA showed a satisfactory result in the maintenance of the aerobic stability and reduction of the silage losses. Trial 2) The same additive tested in laboratory silos was tested on commercial scale silages in bag silos to feed lactating. In a cross over design, the cows were distributed in randomized blocks in 10 pairs of two animals, randomly distributed, within each block, in two treatments (i) silage without additive (control); (ii) silage with Lupro-Mix® NA (4L per ton of natural matter). The results pointed to a numerical reduction in the ingestion time of the animals fed treated silages. Similarly, numerically there was an increase in dry matter intake, milk yield, 4% fat corrected milk, and milk energy, as well as a trend towards increased protein content and yield. The use of Lupro-Mix® NA chemical additive reduces DM losses, improves aerobic stability and dairy cow performance.