At least 11 Conservative MPs have written to the North Shropshire MP to ask for the information which will determine whether pilot culls in Somerset and Gloucestershire are successful.
Earlier this week Mr Paterson, who introduced the cull in a bid to eradicate Bovine TB in cattle, admitted the Gloucestershire cull had killed less than half of the animals it set out to. He has applied to extend the six-week trial that has just finished in Gloucestershire by eight weeks, after it killed just 708 badgers, or 30 per cent of the local population. To be successful 70 per cent of the local population needs to be eliminated, or 1,650 badgers, meaning the trial succeeded in killing 43 per cent of the animals it intended to.
The letter to Mr Paterson, which was drafted by Anne Main MP for St Albans, said: "As you know there remains considerable anxiety within the party about the current pilot badger culls in England.
"There is a need to keep Parliament informed of the results once the trial period has finished and before any decision is made on future culls.
"Now that the pilot culls in Somerset and Gloucestershire are nearing the end of their allocated time frame, we remain concerned that the government will not release any further information on how the humaneness of the cull is being assessed or what threshold will be used to assess if the cull has reached its humaneness target.
"Whilst we appreciate that the Government will release data on the cull, this will only be after you have reached a decision on whether the pilots have met their targets and can be rolled out to wider areas.
"We therefore urge you to commit to publishing the independently assessed evidence from the pilot culls, as well as taking advice from a range of experts on humaneness, after culling in the pilot areas has finished and before any decision has been made.
Mr Paterson was unavailable for comment.