Using silage inoculants to improve the quality of pasture and maize silage in New Zealand

Abstract

Silage is an important supplement in New Zealand dairy systems, however quality can be variable. Challenges with pasture silage lie mainly in the fermentation process, while maize silages tend to have a better fermentation profile, but are prone to heating and spoilage at feed-out. A series of laboratory scale silo trials were used to investigate the effect of different silage inoculants on aerobic stability in maize silage (n=8) and fermentation quality in pasture silage (n=6). Inoculants affected aerobic stability in maize silage, and pH, fermentation losses, ammonia-N and fermentation acid profile in pasture silage, however products differed in their efficacy. Farmers can make better inoculant purchase decisions by choosing products that have supporting trial data as well as guaranteed bacteria numbers.

An investigation of the effects of stage of ensilage on Nassella neesiana seeds, for reducing seed viability and injury to livestock

“…Notwithstanding this, sufficient quantity of lactic acid was produced to ensure efficient silage preservation, so the use of commercial inoculum is positively indicated. By contrast, not using an inoculum resulted in relatively higher concentrations of acetic acid, propionic acid and ethanol 4 21 22 23 24 .…”

“…There is also a positive indication of the development of favourable ensilage profile in the grass species used in this experiment, since relatively more lactic acid was produced with the use of ensilage inoculant. Other researchers have concluded that the production of higher concentrations of lactic acid relative to other organic acids ensures longevity of silage preservation 17 18 19 20 21 24 .…”

“…Additionally, the mechanisms by which seed viability is extinguished through the ensilage process are of interest. Several researchers have investigated the use of commercial ensilage inoculants, which are substances that contain bacteria known to promote efficient conversion of harvested forage to silage, and which produce a variety of organic acids 17 18 19 20 21 . Some of these compounds, specifically lactic and acetic acids, have been implicated in seed viability extinguishment 14 , but have not been recently investigated and nor have they been investigated for their effect on N. neesiana seed viability.…”

“…To determine the minimum time of ensilage required to achieve zero seed viability, as indicated by Viability Adjusted Germination (VAG) (defined in the “Methods” section, below), we used mini-silos 21 to ensile mature N. neesiana seeds within a matrix of shredded and wilted pasture grass, for four different time periods. A commercial ensilage inoculant (a bacterial inoculum) was added to half of the samples, and seeds that had not been ensilaged were germinated as a ‘control’ to compare the effects of time of ensilage and addition of inoculum.…”

Plantain silage quality under variable management practices

“…Low pH caused by lactic acid preserves the forage preventing accumulation of harmful bacteria (Bolsen et al 1996). Management factors which have shown to influence silage preservation and quality include: use of additives (Chamberlain & Robertson 1992;Kleinmans et al 2011), regrowth interval and N fertilisation (Jacobs et al 1998). Consequently, the protocols for ensiling ryegrass-based pastures are well established.…”