Effects of restriction of silage fermentation with formic acid on milk production

Abstract

The study was conducted to evaluate the effects of silage fermentation quality and type of supplementation on milk production. Thirty two Finnish Ayrshire dairy cows were used in a cyclic change-over experiment with four 21-day experimental periods and 4 × 2 × 2 factorial arrangement of treatments. Silage fermentation was modified with formic acid (FA), which was applied at the rates equivalent to 0 (FA 0 ), 2 (FA 2 ), 4 (FA 4 ) or 6 (FA 6 ) litres t -1 grass of pure formic acid (as 100% FA). Dietary treatments consisted of four silages, a protein supplementation (no supplement or rapeseed meal 1.8 kg d -1 ) and a glucogenic substrate (no supplement or propylene glycol 225 g d -1 ). Increasing the application rate of FA restricted silage fermentation curvilinearly, as evidenced by higher concentrations of ammonia N and butyric acid in FA 4 than FA 2 silage. Similarly the use of FA resulted in curvilinear changes in the silage dry matter intake and milk yield. The highest milk and protein yields were achieved with FA 6 , while the milk yield with FA 2 was higher than with FA 4 . Interactions were observed between silage type and supplementation. Rapeseed meal increased milk yield irrespective of the extent of silage fermentation, but the magnitude of response was variable. Propylene glycol was most beneficial with restrictively fermented silages FA 4 and FA 6 . In conclusion, restriction of silage fermentation with a high rate of formic acid is beneficial in milk production. Interactions between silage composition and concentrate types suggest that the responses to supplementary feeding depend on silage fermentation characteristics.

Gas production kinetics in predictions of voluntary intake of grass silage by cattle

“…We did not determine the partitioning factor in this study, which could have been valid to distinguish silage fermentation qualities with regard to energy available for rumen microbes during early hours of in vitro fermentation. The large increase in explained variation of forage DMI from including the partitioning factor would be consistent with observations of higher intake of restrictively than extensively fermented silages (Jaakkola et al, 2006b;. However, to be truly valid in relation to intake the partitioning factor should be measured close to peak microbial yield and before substantial microbial lysis have occured, which can be difficult to address to one time point representative for many feeds.…”

Formic acid treated whole crop barley and wheat silages in dairy cow diets: effects of crop maturity, proportion in the diet, and level and type of concentrate supplementation

“…The changes in the ratio of silage WSC to lactic acid affect the nutrient supply to the rumen microbes, and subsequently modify the microbial protein synthesis and molar proportions of VFA in the rumen (Jaakkola et al 2006a) and affect milk production (Jaakkola et al 2006b). With cereal silage, the intake of starch further complicates the nutrient supply and modifies the rumen fermentation pattern.…”

Effect of dietary formic acid on the in vitro ruminal fermentation parameters of barley-based concentrated mix feed of beef cattle

“…In the Europe Union Feed Additives List, it has been advised that formic acid can add up to 10 g/kg in livestock animal rations (Papatsiros & Billinis 2012;EFSA 2014). This volatile organic acid is used as a silage additive for stimulating the lactic acid fermentation and inhibiting the butyric acid production (Baytok et al 2005) and the conversion of feed protein to non-protein-nitrogen (Jaakkola 2006). However, higher doses of formic acid in diet may cause increasing dietary acidity, disturbing the acid-base status, lowering feed intake, damaging the stomach and duodenal mucosa, and also corrosive structure materials of cage and feeder (Eckel et al 1992;Papatsiros & Billinis 2012) and increase the in vitro methane emission of ruminant feed (Kara et al 2015a).…”