Maximising Weanling Performance this Winter

By John Kilboyle, B&T Drystock Adviser, Teagasc Galway/Clare

Over the coming weeks weanling’s will start to be housed.  The aim is for them to put on 70kg between now and turnout next spring or 0.6kg of live weight on average per day.  This level of performance should not affect compensatory growth at grass next spring.  It has always been suspected that weanlings are not achieving this target at farm level.  A number of years ago a Teagasc study on farms investigated this very question.

Teagasc Weanling Study:

Teagasc examined the performance of weanlings across 17 monitor farms by weighing them at housing and again at turnout.  The main results to come from it showed:

• Only one farm achieved 0.6kg of live weight per day
• Half had a satisfactory performance at 0.55kg per day on average
• The other half had a poor performance at an average daily gain of 0.20kg

The nine farms in the satisfactory group housed their weanlings on average at 348 kg and they gained 82 kg over the winter to come out at 430 kg.  The eight farms in the poor group had a lower daily gain from birth and housed theirs weanlings at an average of 302 kg and then only put on 32 kg over the winter.  Their turnout weight was only 334 kg.  Almost 100 kg already behind the weanlings in the satisfactory group at much the same age!

This study clearly showed that as far as weight for age was concerned the first winter indoors is a period that can cause a serious setback to the lifetime performance of cattle.

There was very little difference between the satisfactory and the poor groups in the quality of silage fed.  Both were feeding on average 67% DMD silage.  This by the way is the average quality of silage cut in this country over the last couple of decades.  All 17 farms also had a satisfactory parasite control programme in place at this time of the year.

The main difference between the two groups was in the amount of meals being fed.  The better group fed on average 280 kg of ration over the winter while the poor group only fed 160 kg on average.  Weanlings are very good converters of meal compared to older cattle.  Money spent on meals for weanlings is money well spent.  A subsequent on farm Teagasc study carried out some years after this one, found that the amount of lying space given to weanlings can also have a big impact on their performance.  Putting too many weanlings in a pen is one sure way of reducing performance.  Taking one or two out of each pen can be a big help to the performance of the whole pen.

Meal Levels for Weanlings:

To achieve 0.6 kg per day over the winter with weanlings you need to match your meal feeding level to your forage quality.  Taking three different silage qualities, the table below shows the amount of meal that should be fed per day over a typical 140 day winter.  It shows the amount per day, the total amount for the winter and the recommended feeding pattern.

For example if you are feeding 68% DMD silage, weanlings should get 2 kg of meal per day with it to achieve 0.6 kg ADG.  However, rather than giving this amount every day right up to turnout it is better to feed more of it at the start of the winter and less towards the end.

Table 2 – Meal feeding recommendations for weanlings on grass silage

* 140 day winter

What Ration?

After you have decided on your level of meals to be fed the next question is what ration.  Whether you are buying in a commercial ration or are deciding yourself on the ingredients, aim for a ration that is high in energy.   Concentrates that have a higher inclusion rate of cereals, maize, pulps, distillers, gluten and soya should be targeted.

As far as protein is concerned, there is evidence from research work done in Grange that the overall diet of weanlings need not be as high in protein as might have previously been thought.  They are recommending an overall crude protein in the winter diet of the weanling of 14%.  With high protein grass silages (16% +) you would in fact get away with straight cereals if you were not feeding high levels.  With more typical grass silages (12 -14% C.P) a ration containing 14 – 15% C.P. should be adequate.