Strategic Parasite Control Around Lambing: Maximizing Ewe and Lamb Health with Closantel and Ivermectin (IVOSAN)
Lambing season presents a unique challenge for sheep farmers: the Periparturient Egg Rise (PER). This period of decreased ewe immunity creates a perfect storm for internal parasites, particularly fluke and worms, to proliferate. Effectively managing this surge is critical for ensuring the health of both ewes and their vulnerable lambs. In this article, we’ll delve into the strategic use of a combination product, specifically closantel and ivermectin (IVOSAN), to combat these parasitic threats.
Understanding the Periparturient Egg Rise (PER) and Its Impact
As we’ve discussed, the PER is a physiological phenomenon where a ewe’s immune system temporarily weakens around lambing. This allows existing adult fluke and worms to thrive, leading to:
- Increased Egg Output: A significant rise in parasite egg deposition onto pastures, creating a high-risk environment for grazing lambs.
- Larval Reactivation: Dormant larval stages of worms like Teladorsagia circumcincta and Haemonchus contortus resume development, further increasing the parasite burden.
- Reduced Ewe Resilience: Ewes are less able to expel existing parasites or resist new infections.
The Strategic Role of Closantel and Ivermectin (IVOSAN)
IVOSAN, a combination of closantel and ivermectin, offers a powerful tool for managing these parasitic challenges. Here’s a closer look at how each component works:
- Closantel: Targeting Adult Fluke:
- Closantel is particularly effective against adult fluke, including those that have matured during the ewes’ housing period.
- Its action is crucial during the post-lambing phase, as fluke populations within the ewe will be maturing, leading to a large output of eggs.
- By strategically administering closantel, farmers can significantly reduce the need for triclabendazole, a flukicide facing widespread resistance.
- Closantel is effective against adult fluke down to 7 weeks of age.
- Ivermectin: Broad-Spectrum Worm Control:
- Ivermectin provides broad-spectrum control against a wide range of internal parasites, including gastrointestinal worms and lungworms.
- It effectively targets various larval and adult stages, reducing the overall worm burden in ewes.
- This helps to reduce the number of worm eggs being deposited onto the pasture.
Optimizing IVOSAN Use During Lambing
To maximize the benefits of IVOSAN, consider these key strategies:
- Timing is Crucial:
- Consult your veterinarian or SQP to determine the optimal timing for administration. They can help you balance the need to protect lambs with the importance of minimizing anthelmintic resistance.
- Treating the ewes shortly after lambing will have a large effect on the amount of parasite eggs that are deposited onto the pasture.
- Accurate Dosing:
- Administer IVOSAN at the recommended dose rate of 1ml per 25kg bodyweight.
- Weigh your animals and group them accordingly to ensure accurate dosing. Underdosing can lead to treatment failure and contribute to resistance development.
- IVOSAN is given by subcutaneous injection.
- Withdrawal Periods:
- Adhere strictly to the 28-day meat withdrawal period.
- Do not use IVOSAN in sheep producing milk for human consumption.
- Integrated Parasite Management:
- Combine IVOSAN use with other parasite control strategies, such as pasture management and rotational grazing.
- Monitor your flock for signs of parasite infestation.
Veterinary Guidance is Essential
While IVOSAN offers a powerful tool, it’s crucial to remember that veterinary guidance is paramount. Your veterinarian or SQP can:
- Provide tailored advice based on your specific farm conditions.
- Help you develop a comprehensive parasite control plan.
- Monitor for anthelmintic resistance.
By understanding the Periparturient Egg Rise (PER) and strategically utilizing closantel and ivermectin (IVOSAN), sheep farmers can effectively protect their ewes and lambs, ensuring a healthy and productive lambing season.
