An on-farm trial aimed at economically improving lamb survival by lambing triplet-bearing ewes indoors and rearing mis-mothered lambs has got off to an encouraging start.
The Marlborough-based Dawkins family is running the three-year trial on their sheep and beef property as part of Beef + Lamb New Zealand’s Innovation Farm programme.
With the support of AbacusBio consultant Simon Glennie, local vet Pete Anderson and scanner Jeff Sewell, Chris and Julia Dawkins and their son Richard set-up an indoor lambing system, drawing on the experiences of farming colleagues and the results of previous triplet-survival and hand-rearing lamb trials run through the Innovation farm programme. These include Andrew and Gretchen Freeman’s triplet transfer system and Matt and Lynley Wyeth’s indoor triplet management and orphan lamb rearing systems.
The Dawkins particularly sought to minimise losses in the week after lambing and Richard says they found they needed to keep a close eye on the triplet ewes and their lambs up to a week after lambing.
While they may appear to have bonded, he says 41 per cent of their mis-mothered lambs were picked up several days after lambing- after the ewes and lambs had left the shed.
Overall, the family achieved a 246 per cent lambing in their triplet mob – this is 320 lambs out of a potential of 390.
Pete Anderson carried out post-mortems on the 70 dead lambs and found the causes of death included abortions, still births, lambs in dead ewes, infections and suffocation.
Triplet survival indoors totalled 95 per cent, with 337 lambs out of 355 surviving birth making it outdoors. Five triplet-bearing wes died.
Richard says there was some mothering on, with 17 triplet lambs mothered onto spare ewes collected from the outdoor lambing beat. The remaining 36 triplet lambs were hand-reared.
How it worked
At mating, the family used ram harnesses to identify mating cycles and the triplet-bearing ewes were then marked at scanning.
Twenty-one days before their lambing date, the first two cycles of triplet-bearing ewes were drafted off and started on a half supplement (1kg of lucerne hay and 150g Reliance triplet nuts) half pasture diet.
One week before lambing, they were run indoors and fed on a full ration of supplement comprising 2kg lucerne hay and 300gms of nuts. This allowed the ewes to become accustomed to both being indoors and the diet.
Once they had lambed, the ewes were put into an individual bonding pen for 24 hours before beginning a gradual transition outside. They initially went into an outdoor holding pen for 48 hours- where they were given pasture and a half-ration of supplement – before going onto a vineyard headland for one week. The Dawkins continued feeding a half-ration of supplement over that week to allow the rumen to readjust and prevent metabolic problems.
After one week, the ewes and lambs were moved onto a high-quality forage of plantain, subterranean and red clover.
Richard says after the first two cycles they decided to modify the system by beginning the supplement 14 days before the ewe’s lambing date and running them into the shed just one day before lambing.
“This eliminated a full week of them being inside and the labour that came with it as well as $7.35/ ewe in supplements.”
They also hastened the transition period to their final paddock, reducing it to five days instead on seven, but the close monitoring continued.
Richard says two days in the holding pen and seven on the headland was quite a lengthy period on average feed.
“While they were still getting the half ration of supplements but really did need to get over to that final paddock of plantain and clover sooner.”
He says they had to find a balance between getting them onto the best feed but also monitoring them closely for long enough (plus allowing enough time for their rumen to readjust to a pasture based diet). Trimming that headland phase down a couple of days was about the only option.
This year the family will be sowing the headland and another paddock close-by in winter-active clover. This means the ewes will have access to top quality feed straight after the two days in the holding pen.
Similarly, after following a strict best-practice shed hygiene routine for two weeks – including changing straw weekly, dipping navels in iodine and disinfecting trough- they eased off what was a labour-intensive routine.
Richard says they had had no deaths from animal hygiene issues – and this clean-bill of health continued even with a more relaxed routine.
He believes their shed set-up and Marlborough’s relatively dry environment contributed to the success of their system. Despite the wet spring, the shed was dry and well ventilated and proved ideal for this indoor system.
“In wetter climates or in a different shed, this relaxed approach may not have had the same success.”
Next week read about the economics of the system and how it impacted on the outdoor lambing ewes.