| 2013-08-14 |    |
Achieving five tonnes of lamb output each year from a tup is a realistic target for commercial flocks with productive ewes, according to EBLEX calculations.
However, its Business Pointers data indicates the average is closer to 2.9 tonnes a tup, making it worth calculating how well an individual flock performed last year and how to make improvements.
Liz Genever
To calculate how much lamb your rams produced last year, multiply the numbers of ewes put to each tup by the number of lambs reared per ewe and then multiply by the average sale weight, says EBLEX senior livestock scientist, Liz Genever.
For example: 70 x 1.71 x 42 = 5 tonnes of lamb per tup.
The first step in achieving a five tonne target is having the confidence to go for the optimum ewe to ram ratio, which needs rams to be fit, ready to work and fertile.
"This year there is a risk that recent hot weather will reduce ram fertility,
as testicular degeneration can occur after over-heating. The scrotum is rich
in sweat glands that cool the testicles if it is able to hang in the breeze.
However, sheep will pant and lie down when they are hot, to transfer heat
away from their bodies through their abdomen," said Liz. "By doing
this, rams are lying on their testicles and ‘cooking’ them. To help avoid
this, ensure rams are shorn, have adequate shade, plenty of water and are
not over-fat. Remember, it takes around seven weeks for sperm to be produced."
So it’s vital to do a simple ram MOT 10 weeks before tupping to allow
replacements to be sourced or treatments to be given. This involves
the five Ts:
Toes - Check his locomotion, arthritis and feet
Teeth - Check for under or over shot teeth, gaps and molar abscesses
Tone - Aim for body condition between 3.5 and 4.0 (spine well covered)
Treat - Ensure vaccinations are up-to-date and check for parasites and lameness
Testicles - Check firmness (they should feel like a flexed bicep) with no lumps or bumps. Measure the circumference around the widest part, with the targets for mature rams being >36 cm and ram lambs >34 cm.
EBLEX
Better Returns Programme (BRP) is working with vets in Cumbria,
Northumberland and Devon, to survey commercial rams before the start
of this breeding season. These vets will be doing more than 200 ram
MOTs, across a range of breeds and locations. The information collected
will be used to understand if and why rams are failing their annual
MOT and the level of fertility problems. Results will be available
from late autumn 2013.
