Background: Nitrite and hexamine are used as silage additives because of their adverse effects on Clostridia and Clostridia spores. The effect of sodium nitrite and sodium nitrite/hexamine mixtures on silage quality was investigated. A white lupin-wheat mixture was treated with sodium nitrite (NaHe0) (900 g t-1 forage), or mixtures of sodium nitrite (900 g t-1 ) and hexamine. The application rate of hexamine was 300 g t-1 (NaHe300) or 600 g t-1 (NaHe600). Additional treatments were the untreated control (Con), and formic acid (FA) applied at a rate of 4 L t-1 (1000 g kg-1 ).
Results: Additives improved silage quality noticeably only by reducing silage ammonia content compared with the control. The addition of hexamine to a sodium nitrite solution did not improve silage quality compared with the solution containing sodium nitrite alone. The increasing addition of hexamine resulted in linearly rising pH values (P < 0.001) and decreasing amounts of lactic acid (P < 0.01). Sodium nitrite based additives were more effective than formic acid in preventing butyric acid formation. Additives did not restrict the growth of Saccharomyces cerevisiae compared to the control.
Conclusion: The addition of hexamine did not improve silage quality compared with a solution of sodium nitrite. © 2018 Society of Chemical Industry.
Keywords: Clostridia; hexamine; qPCR; silage; sodium nitrite; white lupin.
© 2018 Society of Chemical Industry.