Demand for higher-welfare poultry continues to soar on the back of media scrutiny, producers and retailers have claimed.

South-west poultry specialist Lloyd Maunder, a subsidiary of the 2 Sisters Food Group, worked with Jamie Oliver and Hugh Fearnley-Whittingstall in the making of their C4 programmes in January.

The company said it was providing record numbers of higher-welfare chickens in response to growing consumer concern over animal welfare. "Five months down the road consumers are still choosing higher-welfare chicken products," said commercial director Andrew Maunder. "We've been working hard with our local farmers to increase production to meet that demand."

In the next two months the company's indoor-reared Freedom Food labelled chicken would become the biggest part of its production, he added. In January Lloyd Maunder was producing 75,000 chickens under the Freedom Food scheme each week, which represented 15% of its total output. By August it would be producing 250,000 per week under the label, representing 39% of its total output and a 330% increase in seven months, he said.

New RSPCA figures confirmed that sales of higher-welfare chicken continued to rise. Waitrose had increased Select Farm chicken sales by 15% since January, with free-range sales up 22% and organic 39%, said the charity.

Somerfield had seen free-range poultry increases of 50%, with higher-welfare fresh poultry up 40%, taking the level of higher-welfare birds it sells from 5% in January to a predicted 15% by December.

M&S and Asda had also recorded an increase in demand, the RSPCA said.

Meanwhile a further sign of the confidence among breeders of the popularity of higher-welfare birds came with the launch this month of two slower-growing chicken breeds by Cobb Europe. The Cobb Sasso 150 has been developed to meet RSPCA's Freedom Food accreditation and is expected to be available in UK retailers this year.