Lovell, 61, stripped to his socks and shoes and tried to insert his manhood into the cow's mouth in a field next to Tottenham's new training ground.
When the animal ambled off Lovell turned his attention to a bemused ewe and tried to have sex with it from behind.
Jurors laughed when they heard the detail of the case and were told to get over their giggling fits by the judge at Wood Green Crown Court.
Still wearing his beige suit, married man Lovell showed no emotion in the dock as the jury read the verdict.
'This is a case which as far as I am concerned is unique,' Judge James Patrick told Lovell.
'At the moment I do not know what sentence I am going to impose - custody is a possibility, so you should not assume I have ruled that out.'
Tree surgeon Lawrence Stephen, 23, was enjoying picnicking with his girlfriend underneath their favourite oak tree when they were startled by the sight of the married man frolicking with the animals.
'The way he was walking around the field, I could tell that he felt like he was the only person in the field,' he said.
'He seemed like he was very comfortable with what he was doing - as if it was normal.
'He was trying to thrust his waist towards the cows and using his hands to get the cow's mouth towards his crotch,' he said,
'I can't remember him forcing the cow - he wasn't actually grabbing the cow, but he was trying what he could.'
But the cows wandered off into the next field, leaving Lovell to walk over towards some sheep, clutching a can of Skol and a Sainsbury's bag with his clothes in, the court heard.
Robert Hutchinson, prosecuting, told the judge before the trial that the bag also contained an adult nappy.
'The sheep don't stand still, they turn to just walk away or move their head so he was unsuccessful a number of times after going towards the main flock of sheep,' Mr Stephen said.
'I don't know what he was trying to do but it seems he was trying to get some sort of sexual act performed from sheep,' he said.
'I felt sick for what was happening, it sort of disturbed me, I felt worried about him, also it is not right to do that to animals you know?'
Looking visibly shaken, Mr Stephen's girlfriend Natasha Brennan, 23, told the court that she was 'horrified' by the disturbing acts.
'Well, it was quite bizarre.
'I don't think that was normal behaviour and I was concerned for his mental well being,' she said.
Prosecutors claim he was trying to get the sheep to perform oral sex on him and then attempted to insert his penis either into the animal's anus or vagina.
Lovell said he had been sleeping and the idea that he had thrust against sheep was 'completely ridiculous'.
'The only time that I saw the sheep was when I woke up... I was surrounded by sheep about 2 metres away, about 10-12 sheep, something like that,' he said.
'I don't particularly like animals hanging around me when I am sleeping so I sat up and sort of clapped my hands a bit but they didn't take much notice of that so I stood up briefly and stamped my feet on the ground and clapped my hands again,' he said.
'I can understand that somebody from a long distance away would have wondered what was happening when I was trying to chase the sheep away from my location.'
Police claimed when they arrived Lovell had his shorts down, but he insisted they were up at all times.
Prosecutor Richard Hutchinson insisted Lovell was 'interested sexually' in the farmyard animals.
'Mr Stephen and Ms Brennan saw him attempt to make a penetrative motion, thrusting towards the rear of the sheep's vagina or anus again and again.'
Lovell then lay down in the field and pulled his shorts up, the court heard.
The shocked and disgusted couple rang 999 and Lovell was found in the field near Archers Wood by the police and taken to Edmonton police station.
He told the police he was 'just relaxing'.
Lovell of Enfield, was found guilty of outraging decency by trying to commit sexual acts with animals in public places.
He will be sentenced on Friday 7 March and was released on bail until then.
Conditions that he must not go to Whitewebbs Lane or the Archers Wood area were lifted by Judge Patrick.