Maximising Forage: Preserving more from less

4 April 2012

Preserving more from less will enable dairy farmers to improve the value of their silage clamp this season and make savings on bought in feed of more than £4,000 for a 1,000 tonne clamp, according to Volac’s Phil Jones. 

Silage making is firstly about preserving as many nutrients as possible during the fermentation process and secondly, retaining as many of those nutrients during feeding out.  Add the two together and they will help you to make the most of locally grown forage, and ultimately contribute towards improved global feed efficiency. 

The key to preserving more from less is investing in a silage inoculant to ensure efficient fermentation, enhanced stability, improved palatability and subsequent improved yield.  

1, Fermentation: introducing specially selected strains of lactic acid bacteria that can grow rapidly and efficiently improves the efficiency of the fermentation and leads to maximum recovery of dry matter (DM) and protein. The fermentation’s efficiency can be determined by pH, VFA levels, alcohol levels and ammonia levels.  See Table 1. 

Table 1: Treated vs untreated silage analysis

Source: IBERS

 The reductions in ammonia are indicative of less protein breakdown. Earlier research findings at IGER indicated that there was 28.2% more nitrogen retention with  inoculated silage and this was attributed to lower levels of free amino acids and hence less protein breakdown. 

The reduction in levels of other volatiles such as alcohols seen with inoculated silage is also of benefit in relation to interactions with various greenhouse gases. For instance Volatile Organic Compounds (VOC’S) from silage have been identified as significant contributors to the formation of smog in California due to the interaction with oxides of nitrogen.   

2, Aerobic stability: up to 20% DM losses can occur due to microbial activity when forage is opened and being fed out. Although these losses can be minimised through good management practice, silage additives that reduce the levels and inhibit the metabolism of those micro-organisms still present once the silage is exposed to air can significantly contribute to reducing DM loss. Their effectiveness will be determined by the strain’s particular metabolism and can be enhanced by including feed materials such as garlic or other chemical additives which have additional anti-microbial activity.   

3, Palatability and intake: measured benefits in forage quality have been correlated over the years to increases in intake. Trials at ADAS Liscombe with Agros Clamp treated silage showed a 5% increase in intake, however similar research work concluded that intakes may increase by up to 28%. 

4, Milk yield and liveweight gain: improvements in forage quality can improve milk yield and feed efficiency. US trial findings reported an average milk yield increase of 1.4 kg/cow per day in 47% of studies with microbial inoculant treated silage compared to untreated silage.  A further trial at Wye College gave an increase of 1.3 kg/cow per day for Agros Clamp treated silage compared with untreated silage.   

Cost benefits

Back to news