However, demand is rising and there is a growth in the global pig population and a growth in per capita consumption.

With population growth and growth in wealth, the demand for pork products is also expected to grow.

According to the United National the world production of food will have to rise by 50 per cent by 2030 in order to meet the increasing demand.

One of the more immediate issues that is taxing the minds of politicians and the public at large at present is the question of climate change and in this respect production of biofuels are becoming more and more prevalent.

The demand for more biofuels has created competition for land and for cropping areas and this has in turn had an effect on prices both of grain and meat, as production and feed costs rise.

All these factors that are concerns for climate change can also give the pig meat industry as competitive marketing advantage if the correct answers are found and the correct message is delivered.

One of the major concerns that has arisen out of the climate change argument is the realisation that the total set of greenhouse gas emissions are caused both directly and indirectly by products. Every time something is produced it leaves a carbon footprint and it is contributing to the production of Carbon Dioxide, Methane and Nitrous Oxide.

At the recent IMS World Pork Conference in Qingdao in China, Matthew Curtis from the UK pig genetics company ACMC asked the question whether genetics could alter the carbon footprint of pig meat production.

He said that in order to be able to test the theory it was necessary to understand where the main energy usage and emissions were taking place and then to discover whether there are any traits that can influence this.

Once the factors for energy usage have been laid down then it should be possible to create genetic change to improve these traits.

He said that to assess whether these traits should be included in breeding objectives, it was necessary to look at what happened historically to assess future success.

However he added: "Even if it is possible to improve the carbon footprint of pig production, it has to be questioned whether it is economically viable. We need to keep out farmers in business."

A recent life cycle analysis study by Cranfield University showed that across the species - particularly for pig meat and poultry meat - the use of concentrates in the feed uses the most energy.

The study also showed that more energy is used in the production and finishing cycle of production rather than in the breeding cycle.

Mr Curtis said that it has been possible to reduce greenhouse gas emissions and the global warming potential of livestock through genetic improvements and pigs and poultry have a third of the global warming potential of beef and sheep production.

Between 1988 and 2007 genetic improvements had reduced the global warming potential of poultry by 23 per cent and in pig meat production by 15 per cent. The major gains for pigs have come in improvements in feed conversion.

"If you improve the feed conversion ratio then you can improve the carbon footprint," Mr Curtis said.

"Feed intake is important and you need to be feed efficient."

However he said that some breeders do not actually measure feed intake.

He said that slaughter pigs need to put on lean tissue at a fast rate so they have to be feed efficient and feed intake also plays a significant role for breeding sows so that they can have a high reproductive output, and a high lactational output.

Feed is also important for the slaughter pigs through the sows because they proving 50 per cent of the slaughter pig genetics.

Historically up to the 1990s efficiency was achieved through reduced feed intake.

However, Mr Curtis said that limiting feed intake could lead to constraints on growth and sow productivity.

He added that it is necessary to control feed intake in both the sire and dam lines to ensure best growth and greatest sow productivity.

He concluded that the feed conversion ratio is as important today as it has ever been, but it can have an impact on profitability in volatile feed markets.

By optimising the feed conversion ratio helps provide meat for an increasing population and at the same time reduce the carbon footprint of pig meat production.

To achieve the optimum feed conversion ratio, the producer has to ensure the "correct weighting factors for traits in the selection indexes for specialised lines to ensure optimal progress despite possible genetic antagonisms between feed intake and other production traits under selection".

By improving the feed conversion ratio through controlling feed intake and through genetics the carbon footprint of pig meat production can be improved.