Press Release – NZ Veterinarians Association
Veterinarians in western Wellington suburbs have reported treating dogs poisoned by karaka berries.
Dr Brendon Bullen, a representative of NZVA’s Companion Animal Society, practises at Pet Doctors in Kelburn. “I’ve treated one case of karaka berry poisoning at Kelburn, and Karori Vet Clinic has had one suspected and one definite case,” he says.
Karaka is an endemic tree to New Zealand and found spread throughout both the North Island and northern South Island. Karaka trees are fairly well distributed throughout Wellington city suburbs, as well as the Hutt Valley. “Karaka berries are orange, 25-45mm long and produced January to April,” says Dr Bullen.
“They are a major food source for kereru, but the fresh kernels contain the alkaloid karakin which is highly toxic to other animals.”
Owing to their foraging nature, dogs will often hunt out and consume berry kernels, which are plentiful right now across bushy areas in Wellington suburbs. NZVA advises dog owners to take extreme care when walking their dogs, as even consumption of older berry kernels carries toxic risk.
“There is a high amount of variability in the concentration of karakin depending on maturity of the plant, soil factors, climate and season, so clinical signs and toxic dose is variable,” says Dr Bullen. “Berries remain toxic for a long time, and animals can be poisoned by previous year’s fruit.”
Clinical signs of karaka poisoning in dogs are neurological. “Signs include weakness, hind leg paralysis, proprioceptive deficits, progressive dystonia and convulsions which can lead to death,” Dr Bullen explains. “There is often a delay of 24-48 hours between ingestion and clinical signs,” he adds.
Treatment is symptomatic and supportive. Reported cases have taken up to six weeks for normal neurological function to return.