A pensioner from west London has been found guilty of two counts of outraging public decency and banned from every farm in Britain after being caught masturbating with his hand fully inside a cow.

Uxbridge Magistrates Court heard that 80-year-old John Curno had twice been spotted assaulting cows at Park Lodge Farm in Uxbridge, west London.

Farmer Susan Howie told the court that, the first time she saw Curno in her field, he "had his left hand interfering with the cow and his right hand on a part of his lower body [...] he was masturbating – you could see it moving up and down, and his trousers and his boxer shorts were at his ankles".

The second time, said Howie, Curno "had his whole hand in the cow", and when he realised he'd been rumbled "he grabbed his trousers and boxers and he ran for the stile and he actually fell over the stile because his trousers fell down when he was trying to get over it".

"I was disgusted," continued Howie. "We gave nobody permission to touch or interfere with our cows. It might seem funny to you, but they are family, they are not just cows."

Curno claimed he visited a church near the farm once a week merely because he "liked the view" – but, according to two more eyewitnesses, he was there for more than just the sights.

After the pensioner had somehow managed to escape Mrs Howie twice with his pants around his ankles, he allegedly went back for more and was spotted by two sisters, who watched him – from 150 yards away – try to have sex with a cow for up to half an hour. After watching, for some reason, for that period of time, they called the police, who apprehended Curno nearby.

Curno was found guilty of two counts of outraging public decency and banned from every farm with animals for the duration of his bail, but has said he's going to appeal the decision and "sue the police", claiming he hasn't masturbated in three years because of the medication he's on.

"Why would I drop my trousers?" he said. "I never did it. It is their word against mine."