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Case Study: Animal Dewormer



This case involves an equine dewormer used by a horse breeding operation. Fifty-four horses deceased shortly after use of the product, and their owner alleged over $2 million in damages in a products liability lawsuit against the manufacturer of the dewormer. Ultimately, this claim cost the manufacturer $674,000.


LiveStockRx is a manufacturer and distributor of homeopathic and veterinary medical supplies for large animals. Among their products is an equine dewormer that is administered orally to treat and prevent hook worms, round worms, and other intestinal parasites commonly affecting horses.


Mary is the owner of Fairfield Sport Horses, a thoroughbred breeding and training operation specializing in raising and producing racehorses. Mary has more than 70 horses at her farm. To treat them for parasites, Mary purchased and administered the dewormer made by LiveStockRx. Within hours of administration of the dewormer, Mary noticed disconcerting behavior and symptoms of pain in 60 of her horses. These behaviors included drooling, muscle twitching, loss of coordination, apparent blindness, ataxia and collapse. The level of symptoms were not uniform among the affected horses and varied in kind and severity.

The animals were attended to by a veterinarian within an hour of the onset of their symptoms. They were treated with IV fluids and under constant care for the next 24 hours. Despite this, 54 horses died, and the six horses that recovered were rendered lame (and thus useless for racing).


With the help of her attorney, Mary filed suit against LiveStockRx, alleging that the dewormer was responsible for the death of her 54 horses and the laminitis of six. Her complaint enumerated the traditional array of products liability causes of action and negligence in the manufacture and distribution of a toxic product.


Mary claimed over $2 million in damages, the cumulative amount of the fair market value of the horses and/or their likely winnings in a career average of six years of racing. She also had several stallions for which the stud fee (cost to breed to) was more than $10,000, and the fair market value of the animals neared $100,000 each.


Acting prudently, LiveStockRx immediately instituted a recall of the product lots associated with the dewormer used by Mary at an expense of $300,000. Once the product had been recalled, LiveStockRx undertook extensive chemical analysis of the dewormer, also at a significant expense. The results of the analysis, however, confirmed that the chemical composition of the dewormer was fully conforming, and no toxins that could have contributed to the death and illness in Mary’s horses were found. LiveStockRx retained counsel and moved to dismiss Mary’s case. The motion was denied, and discovery was ordered. By way of discovery, LiveStockRx was permitted to have necropsies performed on several of the deceased horses, as well as take samples from the horses’ pasture.

The combination of the pasture samples and horse necropsies revealed a new culprit: a weed commonly known as Nightshade. Indeed, this plant (almost always fatal when consumed by horses) was present in large quantities in the horses’ pasture and in the intestines of those animals that were necropsied.

Armed with this evidence, LiveStockRx was able to win on a motion for summary judgment, and exit the case.


Although LiveStockRx was ultimately able to escape liability for causing the death of the horses, the company still incurred massive expenses in the undertaking of a recall and refunding hundreds of consumers the purchase price of the dewormer, temporarily ceasing production, reporting to the FDA, retaining legal counsel and paying court fees, and performing chemical analysis on its own product, pasture analysis and horse necropsies. Unfortunately, these costs were necessary to avoid a judgment potentially worth millions of dollars.

Ultimately, this claim cost LiveStockRx a total of $674,000.


Even when a manufacturer of animal products produces a safe and effective product, external variables make the probability of a products liability claim real.

Though damages in animal claims are limited—in theory— to the market value of the animal, the legal fees and, frequently, scientific investigations that must accompany defending such a claim can accumulate to become significant expenditures.


  • Frequent Punitive Damages— Though compensatory damages may be limited in such cases, pain and suffering to animals garners an emotional reaction from jurors, frequently resulting in large punitive damages awards against manufacturers of animal products.
  • Role of veterinary experts is crucial— Because of the innate complexity of specialty animal health and the procedures various conditions necessitating intervention, it is usually necessary for both sides to produce veterinary experts, at significant expense, to explain things to the jury at trial.
  • Vet frequently implicates manufacturer— When something goes wrong with a veterinary medical device, it can usually only be the fault of the veterinarian or the device itself. Thus, doctors may be very quick to claim a defect in the product, to protect their own practices and reputations. Of additional concern: vets are more sympathetic to injuries than are manufacturers, and also benefit from malpractice liability caps in many states.

For additional resources contact the Marketing department

Phone: 888-633-6272

Medmarc is a member of ProAssurance Group, a family of specialty liability insurance companies. The product material is for informational purposes only. In the event any of the information presented conflicts with the terms and conditions of any policy of insurance offered from ProAssurance, its subsidiaries, and its affiliates, the terms and conditions of the actual policy will apply.

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