Farm Ireland

Tuesday 12 December 2017

Lamb weights have to meet factory limits

The poor weather conditions are continuing to present problems, making grazing conditions difficult and impacting on lamb performance.

We are constantly hearing of new rainfall records being set, but there will be no records this year for grass-based lamb finishing. Following weaning last month, there has been a growth check for the lambs with growth rates from birth running at 215g/day.

Some of the grass-fed lambs and some concentrate-fed lambs were slaughtered last week but at the time of writing I don't have the factory data on these.

The concentrate-fed lambs are all repeats from the mid- season flock and, as you would expect, have significantly out-performed the grass fed lambs.

Due to the costs of the system I would not recommend it for finishing mid-season lamb, but it does highlight the growth potential that exists within the lamb when they are offered a high quality consistent diet, with minimal (or no) parasite challenge.

This is a message we can all take to managing our grass-fed lambs, bearing in mind the great imponderable that is the Irish weather.

Our ewes held up well during lactation and were weaned with an average body condition score (BCS) of 2.75 for the twins and 2.7 for the triplets (although the triplets were supplemented during early lactation).

Management activities on the farm are focussed on parasite control and foot-care, with our thoughts turning to preparation for the breeding season.

Also Read

A group of French visitors to Lyons last week asked what the main factors driving profitability of Irish sheep production were. Leaving scale to one side, optimising output from the available inputs on the farm is key.

Saleable product on most farms is limited to lamb sales (largely for slaughter but with breeding stock having an important role to play on some farms also).


This will be driven by two important factors, stocking rate and weaning rate. All the data collected indicate that the Irish sheep industry is failing to meet the targets in relation to these parameters, obviously with individual exceptions.

This leads into a discussion about the type of ewe you have on the farm. Our ewes probably average 75kg liveweight just after lambing and wean in the region of 1.6 to 1.8 lambs, depending on the year.

You will frequently hear of systems with ewes around 90-100kg weaning 1.3-1.4 lambs and you would have to wonder what is the benefit of these big ewes?

You will see some growth rate advantage from the lambs but you will still have fewer lambs to sell, your stocking rate will also be restricted by these bigger ewes and they will require more feeding throughout the year. With breeding just around the corner, it is a topic worthy of consideration.

Lamb drafting is also a key issue at this time of year. My in-laws spent the first weekend of July with us in Wexford, when my father (a farmer), father-in-law (a butcher) and I spent some time weighing the lambs at home -- a considerable labour force for the small number of sheep I have.

It was interesting to see the difference in opinion arising between the three of us: a farmer with a lifetime of experience, a butcher with a lifetime of experience and myself.


The discussion about the difference between the butchers lamb and the factory lamb inevitably arose and quality issues including level of finish (fat cover), carcass size and castration of male lambs were all cited by the butcher as crucial elements in producing a quality product.

While I didn't argue, I was paying close attention to the reading on the weighing scales and doing my mental arithmetic to ensure the lambs selected for the factory were meeting the payment cut-off point and I was not giving away lamb for free to the factory.

It is essential that we all keep in mind the market we are producing for when rearing lamb.

There is no point in producing a product the buyer doesn't want and then complaining when he won't pay you for it.

We are producers and, as such, are dependent on our customers satisfaction with our product to ensure our income.

Dr Tommy Boland is a lecturer in sheep production at Lyons Research Farm, UCD.

Indo Farming