A neutered Jack Russell went in to season and started losing fur after being exposed to its owner’s HRT gel.

Owner Sue Burgess was concerned when her dog Rosie began attracting male dogs and showed symptoms of being in season despite being spayed.

She took the three-year-old to North Downs Specialist Referrals (NDSR) after becoming concerned about swelling and hair loss around Rosie’s neck and chest.

The animal hospital, in Bletchingley, Surrey, found Rosie was displaying signs of secondary exposure to hormonal cream containing oestrogen.

Sue had only started using hormone replacement therapy gel around six weeks prior and vets have now highlighted a worrying rise in similar HRT poisoning cases.

Since the start of the year, NDSR said they had diagnosed five dogs with secondary exposure to HRT – which can cause fatal bone marrow toxicity in dogs.

Ms Burgess, from Hove, said: “Rosie had been spayed in October 2021 with no complications, so we were mystified to see her apparent ‘season’.