There are no less than seven different classes of animals for winter feeding on Tullamore Farm. Here, we go through each individual diet and the overall fodder situation on the farm.
A quick look budget on Tullamore Farm’s silage reserves for the current winter period paints a healthy picture – the farm has an overall fodder surplus of over 300t of fresh weight grass silage.
This is assuming an early turnout of weanling heifers (mid-March) and that the light dairy beef yearlings can go straight from the kale crop they’re currently grazing to grass on the driest parts of the farm around Valentine’s Day.
However, in reality, Tullamore Farm is in a pickle regarding silage this winter. Spring-calving suckler farms retaining progeny generally need two classes of silage – one low- to moderate-quality batch for maintaining or taking condition off dry cows and another to drive performance in growing and finishing stock.
Tullamore Farm’s main first-cut this year came in with poor feeding value for two reasons.
Firstly, the field it came off was old pasture with low levels of ryegrass – it has since been reseeded, as has a lot of the farm as part of a front-loaded reseeding strategy which will enable the management to get the most from the farm during the 15-year lease period.
However, it is still possible to get good silage from old pasture if it is managed correctly. The Tullamore Farm silage pasture was only semi-grazed off prior to cutting, with a view to being pitted in early June. However, the window was missed and the crop was cut and harvested three weeks later.
The result is a 770t first-cut that should have had a digestibility value in the 70s now having a digestibility value in the low 60s (Table 1).
The farm was extremely heavily stocked during the grazing season last year as much of the ground was taken out for reseeding. That being said, farm manager Ger O’Dwyer was still able to make over 200 unplanned round bales of surplus grass from the grazing platform.
Ger acted fast during the grazing season, sometimes taking bales from paddocks at a yield of less than five bales to the acre. Given the high demand for grass he had, this was necessary to get paddocks whipped out and back into play for grazing as quickly as possible. The result was one of the best Irish silage tests that I have seen (Table 1, P4 1Sep).
This silage was given to finishing cull cows and weanlings when they came in earlier in the autumn. It is now gone. At time of writing, these cattle had just moved on to the next batch of surplus paddock bales, another excellent-quality batch of which there are 90 bales in reserve (p32 grove).
These 90 bales represent a dry matter stock of 8,700kg and comprise the current entirety of Tullamore Farm’s silage that can be classified as having the ideal feed value for growing and finishing cattle.
Unfortunately, Tullamore Farm’s requirement for high-quality silage this winter is almost 10 times this (Table 2) and there is now a 77t dry matter deficit (350t fresh deficit, assuming 22% dry matter).
It’s decision time now. The obvious steps are to move the finishing cull cows and beef heifers on to a higher concentrate allowance to save this high-DMD silage for the weanling heifers and sheep.
Given that the bug population in the animal’s stomach evolves to digest the type of feed we offer (concentrate versus forage), any move to a high-concentrate diet would afford us the chance to offer these animals poorer-quality silage without affecting performance.
In a high-concentrate feeding scenario, much of the goodness in high-quality silage is wasted if offered to the animal, as the stomach has evolved to digest starch – silage simply acts as a roughage. This roughage is crucial in the diet. There is also scope to push the under-16 month bulls on slightly earlier and move these to poorer-quality silage also.
However, the harsh reality is that even if we freed up all of the high-quality (78% DMD) silage for the sheep and heifer weanlings, we would still be in a massive deficit. We will likely need to feed hay or straw to the ewes and very high rates of concentrate when they come indoors pre-lambing.
The weanling heifers will continue to get the high-quality silage and the energy deficit that comes about when they switch on to the main first-cut will have to be made up with concentrates.
The meal
We formulated two rations for Tullamore Farm this winter (see bottom of facing page). The growing ration is being fed to the weanling bulls and heifers. The bulls will move on to the finishing rations as they approach their first birthday and the cull cows and three beef heifers are currently on this ration.
Simple quality ingredients were used - many of which have proven themselves in recent research. Maize meal has been shown to increase growth, carcase weight and feed efficiency when replacing barley in bull finishing rations.
Molasses is included to drive palatability – crucial for encouraging intake when feeding young stock – and also to keep dust down – maize meal is an exceptionally dusty feed ingredient.
Our weanling ration contains a combination of a live yeast and a mineral mixture at a rate of 2%, while the finisher ration includes minerals and a rumen buffer product at a combined rate of 3%.
The rations were formulated using the net energy and protein systems. These are based on absolute energy available for maintenance and growth once all other needs have been met, and absolute amount of protein arriving in the animal’s small intestine for digestion.
A small number of feed companies use these systems in Ireland currently, though many still use metabolisable energy (ME). This system does not take into account the energy required to digest the feedstuff. Thus, it is slightly less accurate.
While the crude protein concentration on the rations presented here may come in below what is being marketed across the country, the net protein (PDI) values are generally similar.
This is based on the purity and quality of soya bean meal as a protein source. At the end of the day, crude protein is simply a multiplication sum based on the concentration of nitrogen in an ingredient.
Dry cows on track
Dry cows silage thin and maiden heifers
Dry cows kale
Cull cows
Weanling heifers
Weanling bulls
Dairy beef calves