This is my third year writing on the issue of silage quality. At this time of year, the effects of poor and average quality silage start to become clearly visible through disappointing winter performance. From the hundreds of silage samples that are presented to me to formulate rations around, I have seen a continued trend of low levels of both energy and protein, poor preservation and depleted mineral and trace element profiles. These types of results have been common for many years.
For someone who works on both sides of the border, the contrast between silage qualities is very stark.
North of the border there is a much greater emphasis on ensuring that the silage is of consistent drymatter, energy and protein levels are optimised, and the correct pH is achieved for fermentation. It's the norm rather than the exception to see silages on Northern beef farms higher than 75 drymatter digestibility, protein levels over 14pc, pHs within the ideal range of 3.8-4.1, and drymatters between 25-30pc.
Why are these standards not being achieved consistently by beef farmers in the south? Is it the weather? Soil types? Grass varieties? Crop yield? Advice on offer to farmers? Contractors? I regularly hear a combination of these reasons being offered while standing at the face of a sub-standard pit of silage or looking at a poor silage analysis sheet.
Contrary to common views, grass silage is a very expensive feed to produce, which further rises in cost as quality decreases. As silage is produced primarily for its energy content, the poorer the quality the more expensive it becomes.
Collectively, farmers and advisors must move away from the notion that grass silage harvesting is only carried out to facilitate good grassland management. Also, in many cases, grass silage is viewed as being a filler for growing and finishing beef animals rather than an important energy component of the diet. If a filler is required, straw is a much cheaper option.
The margins within all beef production systems demonstrate that there should be no let-up in performance during the lifetime of an animal.
The tradition of storing animals over the winter and allowing for compensatory growth when they hit grass, in my opinion, has no place in a modern, quality beef production system. Average to poor quality grass silage only facilitates this practice.
Factors such as harvest date, grass variety and harvest management are all within the farmer's control and can have a huge bearing on silage quality. A return to the basic principles of correct slurry and fertiliser application time, spring rolling to avoid soil contamination at harvest, analysing grass for nitrogen and sugar levels prior to harvesting, mowing from late morning onwards, allowing for a moderate wilt, applying a suitable additive and clamping and covering as rapidly as possible will all contribute to improvements in quality.
None of the above are methods that farmers weren't practicing 40 years ago, which leads me to question why they are being currently neglected. I feel the onus is on Teagasc to ensure that the quality of our grass silage production does not continue to spiral downwards. The great work carried out over the years by Dr Padraig O'Kiely at Teagasc's research centre at Grange needs to be re-emphasised. Excellent work has been carried out on maximising the utilisation of grass at grazing time, which beef farmers have benefitted hugely from. However, there is an obvious need for an equal emphasis to be placed on the area of silage making.
Another area where attitudes north and south differ is on the use of silage additives. A much broader view is taken by farmers, contractors and advisors in Northern Ireland.
Rather than continuing to make below average quality grass silage, it may make more sense for some farmers to grow or source an alternative forage such as cereal wholecrop or maize silage.
These crops are more consistent, will ensile better and will guarantee performance, while having a lower cost per unit energy compared to the majority of grass silage that is currently the norm throughout the country.
Gerry Giggins is an animal nutritionist based in Co Louth