SCOTLAND'S second biggest pig farmer has been thrown out of a quality assurance scheme after investigations uncovered serious breaches of animal

welfare.

Quality Meat Scotland (QMS), which ensures pork is produced in top conditions ''from the farm gate to the plate'', said it had run out of patience with Scotpigs, run by Arthur Simmers, known as King Arthur in the industry.

It said it was not prepared to let ''one rotten apple in the barrel'' wreck the industry's reputation north of the border.

The move came as animal welfare activists released secretly-filmed footage of the conditions they found on several of the company's premises.

Advocates for Animals found bins overflowing with dead pigs, rat infestation, pigs biting at the flesh of dead pigs, and animals with open sores.

One investigator said: ''I've been on many pig farms in the UK, but these were the worst I've seen.

''The stench on the farms was overpowering and we saw a seething mass of rats running in and out of the sheds. If a pig can be allowed to lie there rotting, one has to wonder what else can go unnoticed?''

QMS has criticised Scotpigs before, throwing two of its farms, one in West Lothian and one in Aberdeenshire, out of the quality assurance scheme since the turn of the year. This week it took similar action against four others.

The move means that, with ''non-assured'' pigs having no outlet in the Scottish industry, the company's market north of the border has been virtually eradicated.

This has led to Mr Simmers, credited with helping to pioneer modern pig farming in the 1960s, seeking business opportunities in England, where he is also facing prosecution for conditions at one of his farms in Melton Constable, Norfolk.

Mr Simmers, a former chairman of the Scottish Pig Association, has previously been cleared of charges of animal cruelty. He was not available for comment yesterday.

The action by QMS, which said the industry was justifiably proud of standards and would not allow individual companies to bring the whole sector into disrepute, coincided with the release of film from the undercover operation.

Advocates for Animals infiltrated four Scotpigs farms in the past week: Mains of Bogfechel and Woodlands, both Aberdeenshire; Muir of Perth, Tayside; and Ormiston Farm, West Lothian.

Last year, animal welfare inspectors described a rat infestation at Ormiston as one of the worst they had ever seen.

Advocates for Animals said the state veterinary service and Scottish SPCA had been told about the new findings.

Ross Minett, its campaigns director, said: ''These intelligent and sentient animals are being kept in terrible conditions. I'm sure people will be disgusted to see how pigs are treated behind the closed doors of Scotland's factory farms. This is the shameful reality of modern intensive pig farming in Scotland.''

Mr Minett said this was its third visit to one of the farms yet nothing had changed.

''The Scottish Executive must start taking the welfare of farmed animals seriously and stop turning a deaf ear to our pleas for action.''

Scotpigs was set up after Mr Simmers's previous pig breeding business went into liquidation in 1998 with debts of (pounds) 10m.

The failure of the original empire, which was Scotland's biggest pig breeding operation, was blamed on the collapse of pig prices.

The state veterinary service confirmed yesterday that officials were visiting the farms to investigate welfare allegations. Findings may be reported to the procurator-fiscal.

A spokesman for the SSPCA said it had been monitoring the situation. Welcoming the QMS move, it said: ''It has been made clear by Scotpigs that we are not welcome on their premises.''