Stamina Plus has not seen Pin Worm infections in its research horses for the last 25 year, even though horses are purchased yearly.
This week one of the horses purchased 6 months ago and housed in a pen with one other horse developed a Pin Worm infection with classic signs of irritation to the perineal area, with severe rubbing and loss of hair. This horse has been wormed with both Ivermectin and Panacur over the last 6 months.
There have been reports of resistance to both of these products.
If your horse develops signs of Pin worm infection it would be advisable to contact your Veterinarian for treatment options.