
In autumn, harnesses will indicate whether a ewe has been mated and these ewes can then be taken off high quality “flushing” forages and put back onto maintenance rations (with a back-up ram).
The Hodgen family, who farm in North Canterbury, found the use of ram harnesses has thrown some surprising results. They discovered 93% of the ewes were mated in their first cycle and so could be put straight back onto maintenance feed with a follow-up ram.
“It’s phenomenal how much feed we have saved for the price of ram harness and crayon,” says Dan Hodgen.
The ewes remain marked and at set-stocking are run in mobs according to their mating dates. This means the family is not set-stocking earlier than they need to and management over lambing is much more targeted.
Reece Cleland manages the 2700ha Annavale Station near Springfield in Central Canterbury. With limited cultivable country upon which to grow high-quality feed for flushing their 4,500 ewes, he has found ram harnesses to be a cheap and easy way to ensure this feed is partitioned into the ewes that need it.
He says he begins flushing the ewes a fortnight before the harnessed rams go out. The rams are out with the ewes for 32 days. When the ewes are marked they are removed from the mob and run out onto the hill country with a follow-up ram.
Reece drafts the ewes every three to four days and finds that 90 per cent of ewes are mated within the first cycle.
Scanning results showed that the ram harnesses were “surprisingly accurate.” Reece says out of the 50 ewes that weren’t marked 25% were dry.
Canterbury-based farm consultant Wayne Allan says there are pluses and minuses to using ram harnesses – but they can provide valuable information that can help in the allocation of feed resources and management around mating and lambing.
He says today’s ewes tend to be heavier and more fecund, so a higher proportion of the flock can be mated within the first cycle (80-90%). If marked, these ewes can be put back onto maintenance – although Allan cautions against under-feeding ewes at this stage.
At lambing, the marked ewes can then be managed according to their lambing date, so later-lambing ewes can be set-stocked later which again provides an opportunity to be more strategic with feed resources.
Allan points out that foetal aging at scanning does provide this same information, but it is slightly more expensive and doesn’t allow for feed management over mating.
He says the downside of ram harnesses is the work involved in changing crayons and, on properties with a lot of scrub, there is always a danger of the harnessed ram getting caught up, or losing crayons.
On larger, extensive, properties with large numbers of rams, the logistics of finding rams and changing crayons can make them a less impractical option.
Where the focus is on determining when rather than whether the ewes have been mated, Allan suggests not putting the harnesses on until 10 – 17 days into mating. This reduces the workload and means unmarked ewes will be early lambing or are dry.