Choosing a Silage Inoculant
For high yielding herds the demand for silage to improve overall intakes and have maximum palatability to sustain production is greater than ever. 2nd 3rd and 4th cut grass, whole crop and maize do contain the ideal nutrients for a balanced diet of protein, starch, sugar and NDF. The requirement of inoculants is to keep these nutrients in a form available to cows and their rumen bacteria after ensiling.
Probably the most important requirement to achieve from silage is stability. This is essential for high intakes along with a pH that doesn’t dip too low. High sugar, leafy grasses offer more potential for the anaerobic lactic acid bacteria (lactobacillus) to convert more sugar into lactic acid. Although lactic acid is an energy source for rumen bacteria, intakes can be impaired.
To consistently achieve stable silage over a wide range of crops and dry matters choose an inoculant which actively combats spoilage organisms on the crop e.g. yeasts, moulds, listeria, clostridia. The bacillus strains, B Subtilis and B Pumilus used in combination has proved successful on UK dairy farms over the past 13 years. The benefits are seen in higher intakes and healthier, more productive animals and is supported by research at Lancaster University and Kingshay. Stability was the key focus and how this impacts silage wastage.
These bacillus are most active in pH range 7 to 5, where a good fermentation needs to be quickly established as spoilage organisms use vital nutrients and create patchy silage. If a 24 hour wilt is achieved, followed by efficient harvesting and good clamp compaction in the pit, the next 24 - 48 hours are crucial in establishing palatability. After this time the silage pH will be below 5.00 offering the ideal environment to naturally occurring lactobacillus present on the crop. These further acidify and stabilise the silage to pH 4, or with very young material 3.8.
To optimize the microbial activity in the rumen ideally a combination of crops should be offered in the TMR. For farmers who cannot grow whole crop or maize, round bale silage complements high quality clamp silage for maintaining rumen pH. Cows need longer fibre to help with cudding but the energy is less available to the rumen microbes and often passes though undigested. A new enzyme used in conjunction with bacillus strains successfully opens up the bound fibre to enable the microbes to use up to another Mj/ME /kilo of DM intake.
Mr Rogerson of Game Farm, Singleton said of the combination “We achieved higher yields than ever from forage last winter as well as increases in butterfat and protein of 0.3% and 0.2% respectively. Cow condition has never been better and we have reduced our calving interval.”
Roy Fawcett of Edinburgh based Bioparametrics said “when comparing analysis we noticed the NDF fermentation rates increase and lag times reduce with the combination inoculant which increases the available energy supply from the forage”.
