Store lamb sales are off to a positive start across NI, with prices up £10 to £15 year-on-year.
Buying competition is most intense for short-keep lambs in the region of 38kg to 40kg, with prices currently in the region of £100 to £110.
Lambs closer to weights around 35kg to 37kg are returning prices of £90 and above, particularly for animals with a strong Suffolk and Texel breeding influence.
Crossbred lambs at similar weights, but exhibiting a greater hill-breeding influence, are typically selling between £80 and £90.
Lighter lambs are a more difficult sell, with prices between £60 and £70 for hill lambs just weaned, rising to levels around £75 for stronger-framed animals.
Budget
For farmers new to purchasing store lambs, it would be worthwhile to draw up a simple break-even finishing budget before committing at a sale.
Key information for a budget includes purchase price, starting weight, target weight gain to slaughter, grazing costs and concentrate feeding.
Be aware that lambs are normally sold without weighing in the ring and pens are often a mix of male and female animals.
Weight gain
Good quality lambs are capable of gaining 150g to 200g/day on well-managed grazing swards in August, equating to 1kg to 1.4kg of liveweight per week.
In September and October, dry matter in grass will drop, resulting in lower liveweight gain from a grass only diet.
Weight gains of 0.75kg to 1.25kg/week are more realistic in late autumn, easing back towards 0.5kg to 1kg/week for hill-bred lambs.
Introducing concentrate will boost weight gain as grass quality and supply declines during autumn, but comes at a cost.
Example
As an example, take a farmer buying 50 crossbred lambs in mid-August to graze 10 acres after second-cut silage.
Lambs cost £98/head and average 37kg arriving on-farm. Target drafting weight is 50kg, which at 42% kill-out will yield a 21kg carcase.
Lambs average 1.25kg/week from mid-August to 30 September from grass only. From 1 October, lambs eat 0.25kg/day of concentrate (£280/t) and gain 1.1kg/week.
That means lambs reach slaughter weight by mid-November. Assuming 50 days of concentrate feeding, 12.5kg of concentrate is consumed per lamb at a cost of £3.50.
The 10-acre field receives 27 units/acre of CAN costing £325/t, meaning grazing costs come to £163, or £3.25/head. There is also an oral drench to kill parasites, costing £1/head.
Purchase and input costs come to £106. Factoring in a £20 profit margin, a factory price of 600p/kg on a 21kg carcase is required to breakeven.
Considerations
The example assumes that all animals are capable of high levels of weight gain from grass and there are no losses within the lambs purchased. However, in reality, it might be prudent to factor into the budget a 2% mortality rate.
When it comes to meal feeding, energy and starch is most important in a finishing ration. Grass should provide adequate protein in late summer and early autumn.
Therefore, there is scope to lower feed costs by offering a predominantly cereal-based ration to encourage fat cover in lambs.