There is a definite pattern starting to emerge from regularly testing my silage bales and I am almost tempted to say that as the dry matter rises, the D-value drops correspondingly.
This means that, on paper, low ME figures (9.3-10.6) are suggesting that I have made a pile of fodder with little or no feeding value, and yet I am perfectly happy to be offering this stuff to my pregnant ewes.
I realise that I have banged on about this before, but it is of overwhelming importance that sheep gorge themselves on whatever material is offered, and over the years, my experience is that the best way of achieving this is to make high dry matter (DM) silage in a bale.
If I ignore the low energy analysis from my samples, most other aspects are roughly where I want them to be. Dry matter is generally in excess of 40%, sugars are mostly above 4% and protein is averaging an acceptable 11%.
I am not trying to make excuses for making low energy fodder – it just seems that the more I tedd grass out to make something approaching haylage, the more adversely it appears to affect D-values.
All grass was mown during the last days of May and while some of it was more advanced than I would have liked, I was well pleased with how it looked at the point of wrapping.
When the first bales were opened and offered to in-calf dairy heifers, I carried out a visual analysis of my own, along with a simple taste test involving one bale from each of four different fields.
My visual assessment was slightly back to front and the stemmiest looking grass (DM of 30%) couldn’t possibly compare favourably with the 46% DM material that looked great and smelled like a summer’s day. I was wrong and I was possibly wrong on two fronts.
Firstly, the harder looking 30% DM silage analysed better (for energy) than the very dry grass and secondly, the cattle preferentially ate it (although they readily consumed all the bales). It will be interesting to see what the sheep have to say about it.
I suppose the six-million-dollar question is whether or not I would put my money where my mouth is. If I were given the choice to buy high energy, lower dry matter bales, or lower energy, high dry matter ones, which would I choose?
Honestly, the high dry matter option (for sheep) offers a more guaranteed fermentation in my experience, with the added bonus of a heck of a lot more feeding material in each bale. Ease of handling, particularly around individual lambing pens, is another advantage too.
It has been a funny old year and there are plenty of anecdotal stories of first-cuts analysing poorly compared with other years. I assumed this was because of delays in harvesting dates, but one nutritionist also suggested a lot of May-cut grass just did not analyse as well as expected.
Moving forward into next year, the high cost of making any sort of silage has to be balanced against record prices for concentrate feeds. I know that, theoretically, small crops of high-quality grass should help to offset expensive meal, but I suspect that I’ll continue to aim for ten-to-the-acre, very dry bales.
That really does lower the feed cost per unit significantly. Maybe I should stop analysing the bales and just tell the whole world that my silage is “quare stuff”.