The declaration agreed by all EU countries in 2010 stated that surgical castration should be phased out by 2018 and that castration would only be performed with prolonged pain reducing medication (analgesia) and/or anaesthetic by 2012.

The goal of this is to reduce discomfort and pain to the animals caused by castration. The researchers say that effective protocols and guidance on the use of these medicines needs to be established by the EU if they are to meet the terms of the declaration.

With the 2012 deadline already gone and only a short time left until the 2018 deadline, the vast majority of EU countries are still surgically castrating animals, many without effective pain relief.

Survey data and interviews with specialists from EU countries revealed that in 18 out of 24 surveyed countries more than 80 per cent of pigs are surgically castrated. Germany, Norway and Sweden are the only three countries to ensure that all of their castrated pigs are given either anaesthesia or analgesia.

Across the EU countries surveyed just over 40 per cent of castrations involved either medication.

The UK fared poorly in comparison with 91 per cent of its castrations taking place with no pain management at all. However, the UK only castrates 2 per cent of its male pigs, bettered only by Ireland which does not carry out any castrations. The authors suggest a farming model which involves no surgical castrations is one that could be taken up by other EU countries to help fulfil the 2010 declaration. However, farmers, buyers and consumers have concerns over boar taint in meat from male pigs that have not been castrated.

The main reasons cited by respondents to the survey why the declaration was not being met were that use of analgesia and anaesthesia was not practical for reasons including extra costs and work to the farmer and a lack of workable protocols. For example, in some countries a vet or specialist is only allowed to administer the medication.

The study was conducted by researchers from Sweden, Germany and Spain, and was commissioned by the Federation of Veterinarians of Europe and the European Commission.