The British Government's draft Animal Health Bill has been published, with horse owners unhappy authorities have failed to address provisions they say will impose what is effectively a tax on horse owners.
The planned law provides for a levy on horse owners to help pay for a new Government agency to oversee animal health.
Horse owners have been critical of the plans since they were published last year, with many angry that the proposed new system of charges would place a heavy burden on the horse sector without offering any clear benefits to equestrians.
The equine industry says the proposal amounts to a tax in all but name.
The draft bill was published on January 24.
The British Horse Society said: "Despite Minister for the Horse Jim Fitzpatrick telling MPs that the Government is 'keen for there to be as much scrutiny as possible', the publication of the Bill comes well before a cross-sector Advisory Group set up to examine the proposals has had a chance to have its say."
Critics have pointed to the poor value for money which taxpayers would receive from a new organisation, arguing that any new body would spend much of its time collecting charges from people who own just a single horse - a group that makes up 65 per cent of all owners.
With the administrative cost of collecting the charge almost outweighing the charge itself in these cases, an estimated £2.3 million would need to be spent to collect just £4.5 million, says Rethink the Horse Tax, the campaign behind the petition.
Veterinarians, too, have warned that creating a new layer of bureaucracy will complicate the process of responding to animal disease outbreaks.
Welfare groups have also joined animal keepers and vets in expressing opposition to the plans, as they artificially separate animal health and welfare.
Mark Weston, Director of Access Safety and Welfare at The British Horse Society, said: "It seems ridiculous to issue this bill before the cross-sector Advisory Group set up to examine the proposals has had a chance to have its say.
"As it stands at present the bill does not contain sufficient detail and it is a real concern that equestrians will not have a proper opportunity to comment on the detail if it is to be brought into effect by secondary legislation rather than being set out in the Act."
The British Government recently published a Draft Bill on Cost Sharing in respect of the so-called "horse tax".
Horse Minister Fitzpatrick has agreed to attend the next meeting of the All Party Parliamentary Group for the Horse on March 2 to answer questions on the draft bill.
The group was set up by The British Horse Society in 2005 to raise the awareness of politicians to issues affecting all equines. The group meets three times a year, and the secretariat is provided by the society.
The society says ministers are under pressure to reconsider its plans over the tax, with a petition in opposition attracting more than 10,000 people.