The amount of Freedom Food labeled products in supermarkets has also increased 30 per cent in the last two years.

It is further proof, says Freedom Food, that ethical shoppers remain committed to farm animal welfare despite a tough economy.

This news echoes a prediction at the Oxford Farming Conference by Dr Alan Renwick that: “People buying RSPCA Freedom Food are more likely to stay loyal during the recession than organic buyers.“

It also follows The Co-operative Bank’s latest Ethical Consumerism Report (2010), that sales of Freedom Food labelled products tripled in two years to reach 3122m.

Freedom Food saw a rise in animal numbers from more than 49m at the end of 2006, to more than 75m at the end of last year. This means that about 26m more animals are now benefitting from being reared to the RSPCA’s higher welfare standards, compared to five years ago.

Pigs up 84 per cent

The number of pigs under Freedom Food has grown nearly 84 per cent - from 1.4m (2006) to 2.7m (2011) - including a 16 per cent increase last year. This means pigs farmed under Freedom Food to RSPCA standards now account for about 28 per cent of UK pig production.

Chickens rise 60 per cent

Chicken numbers have risen 60 per cent in five years - from 25m to nearly 40m birds – with a 13 per cent rise last year. This accounts for about five per cent of the 860m chickens farmed every year in the UK.

Other key figures:

Egg laying hens increased 53 per cent overall from 11.6m to 17.8m birds, despite a 6.28 per cent blip last year. This means the vast majority of UK cage-free egg production is under Freedom Food.

Ducks rose 21.5 per cent from about 3.8m to nearly 4.7m but took a 28 per cent fall last year. However, this still accounts for about 36 per cent of UK duck production.

Turkeys quadrupled from just over 247,000 in 2006, to more than 1.2m birds. However, Leigh Grant, Chief Executive of RSPCA Freedom Food, said: “The trend for ethical purchasing has had a huge impact on farm animal welfare. Consistent consumer demand for Freedom Food products has helped millions more farm animals have a better life than they did just five years ago.

“But despite this growth, only around eight per cent of the UK’s billion farm animals are under Freedom Food. And with some animals like ducks and turkeys dropping in number last year, there is clearly still much more work to do.

“And we need people to help us. The more shoppers demand Freedom Food products, the more supermarkets will stock them and the more farm animals will have a better life.“

There are now more than 900 different Freedom Food labeled product lines available in major retailers, independents and online. These include chicken, eggs, salmon, pork, duck and dairy products.