To treat or not to treat?

To treat or not to treat?

25 February 2019

As autumn approaches it’s time to start thinking about protecting your cows from worms.

There is no denying parasites affect adult dairy cows, impacting milk production and body condition1,2,3. The good news is both local and overseas studies have shown improved production in treated cows4.

Gains of four kilogram (kg) milk solids (MS) per cow on average were demonstrated in New Zealand studies. A trial at dry-off compared the effects of using a long-acting treatment versus a short-acting one to assess the impact parasites have on cows. Those treated with Cydectin® Pour-On (the long-acting treatment) produced on average 4.2 kg MS more than cows treated with the other drench4. The Cydectin-treated cows achieved better results because the parasite larvae present on the grass were prevented from establishing an infection in the cow, helping stop a cascade of production loss. These larvae can be present in large quantities, particularly in the autumn. Pasture contamination is worse where younger animals graze on the milking platform or if cows are forced to graze low feed covers. The cow’s immune system mounts a response to the ingested parasite larvae, costing the cow in terms of protein and energy which subsequently can’t be used to produce milk or gain weight. Controlling parasites for longer removes the need for the cow’s immune system to respond, hence production improves.

A targeted approach to treatment is more economical and is a sustainable way to delay drench resistance over a blanket approach. At-risk cows to target for treatment are those that were sick, lame or had mastitis during the season, young cows and any with low body condition scores. Cydectin Pour-On has a nil milk withholding period so treatment can be applied at any time during the lactation cycle. And, if the cow doesn’t make the grade by dry-off and has already been treated, she can still be culled as Cydectin Pour-On also has a nil meat withholding period (including bobby calves). These nil withholding periods, combined with persistent activity against key production-limiting worms, make Cydectin Pour-On an ideal treatment option to maximise the performance of your herd.

1 Charlier, J, et al. Gastrointestinal nematode infections in adult dairy cattle: Impact on production, diagnosis and control Vet. Parasitol., 2009
2 Gross, S.J., et al. Anthelmintic treatment of dairy cows and its effect on milk production. Vet. Rec. 1999
3 Sanchez, J., A meta-analysis of the milk-production response after anthelmintic treatment in naturally infected adult dairy cows. Prev. Vet. Med. 2004
4 Murphy A, The effect of treatment with moxidectin, a long-acting endectocide, on milk production in lactating dairy cows. Buiatrics, 1998 Zoetis New Zealand Limited. Tel: 0800 963 847; www.zoetis.co.nz. Cydectin is a registered trade mark of Zoetis. ACVM No. A6203.

If you think your cows may need a worm treatment this year, talk to your local Farm Source TSR about Cydectin Pour-On or visit your local Farm Source Store.