SAC Research

Recent research at SAC has shown that:

• Lambs reared on chicory without drenches had lower worm egg counts than lambs grazing grass/clover, and grew at similar rates as lambs reared on grass/clover with drenches. 
• Short term grazing on chicory can result in reduced worm numbers.

Lambs grazing on chicory cope well with parasites and grow as well as if they were drenched with wormers

Targeting The Ewes
From weaning their lambs to mid pregnancy, ewes are usually resistant to worms. Then, twin-bearing and rearing ewes are less resistant to worms than single bearing and rearing ewes, whilst barren ewes continue to remain resistant.

Single rearing and barren ewes can safely graze your more dirty pastures, but speak to your vet to determine worm egg counts on mob (bulk) samples.

Focus worm control strategies on the twin-rearing ewe (HISHA Leaflet and MOSES leaflet). One of the options is the targeted drenching i.e. drench the ewes that actually need it (SCOPS). Nutritional interventions can also be considered to reduce wormer use.

Recent research at SAC has shown that:

• Feeding twin-rearing ewes on more protein increases milk production and reduces worm egg output with more than 60%. This was achieved through feeding ~20% more protein than what is usually advised. These benefits can be achieved within a matter of days.
• Ewes in a good condition have less worm problems; a condition score around 2¾-3 in the last few weeks before lambing can help to reduce worm egg output during the lactation period. 

Protein supplementation to twin-rearing ewes has a double benefit. On the one hand, it reduces the ewe’s contribution to pasture contamination with worm eggs, which, in turn, reduces worm challenge to their lambs. On the other hand, protein supplementation results in increased milk production. Both reduced worm challenge and increased milk production result in improved lamb growth performance.

Feeding twin-rearing ewes more protein gives you fewer parasites and heavier lambs quicker!!

Integrate nutritional control measures to your worm control strategy. Discuss these opportunities with your adviser, to reduce your costs of wormers and help to reduce the rapid development of drench resistance.

Current work at SAC is looking at the combined effects of protein supplementation around lambing and subsequent grazing on chicory plots. Preliminary results show that the combined use resulted in lower parasite burdens and better performance compared to either of the effects alone.

Further research on how the nutritional options can affect parasitism in breeds that differ in perceived worm resistance (e.g. Blackface sheep are considered more resistant than Greyface sheep) is currently being carried out.