Can science take pain and guilt off the menu?

Breeding animals that feel no pain

by Melody Thomas, science columnist

Ultimately, do our morals and ethics hold any sway over the way that we consume food? The increasing popularity and marketability of free-range meat products seems to answer in the affirmative. Apparently humans do care about the lives the beasts on their plates have led, before they were herded naively into the slaughterhouse. In his recently published paper “Knocking out pain in livestock: Can technology succeed where morality has stalled?” – the American academic Adam Shriver (his background is in philosophy, at Washington University, St Louis) offers a brand new technological solution to the issue : that is, by calling for the minimising of the suffering in animals, as a means of minimising the moral suffering in humans.

Shriver postulates that the vegetarian and animal rights movements aren’t moving fast enough to eliminate factory farms altogether, and that those who find these farming methods cruel or inhumane have a responsibility to at least consider what technology is close to allowing us to do – that is, genetically modify factory farm animals so they no longer feel pain.

It is almost impossible to deny that factory farmed animals suffer. Until recently, it was possible to believe that clean, green New Zealand factory farms treated their animals with more care than their international counterparts, but Mike King’s expose on the New Zealand pork industry has certainly taken the wind out of that argument. It doesn’t matter what your biology teacher told you about not attributing human emotions to animals, research supports that factory farmed animals often live lives of physical and psychological affliction.

The cows that produce our milk for instance, have been shown to display signs of distress when their calves are removed from them – a process which is done about once a year to keep their milk flowing more or less continuously. This near-constant state of lactation means anywhere between 38 and 49% of heifers have the intramammary bacterial infection mastitis (ask a human mother if this is a painful condition).

Pigs living in ultra-confined spaces like those we saw on television recently suffer from sores on their shoulders and knees, obesity, crippling leg disorders and neurotic coping behaviours like repetitive bar biting or sham chewing (chewing nothing). When it comes to the slaughterhouse most slaughters are quick – but there is always room for human error, and there will always be a few who are not slaughtered correctly and are therefore left to die more slow and painful deaths. Pigs who are not correctly stunned at the beginning phases of slaughter can remain conscious until they reach the ‘scalding tank,’ where they are then boiled alive. When it comes to lowering animal suffering at the hands of humans, a life of vegetarianism is the most obvious answer. But although the number of vegetarians in the world is steadily increasing, the amount of meat we consume is increasing much, much faster.

Official statistics from the UN Food and Agriculture Organisation (FAO) put worldwide meat consumption at over 250, 000, 000 tonnes per year (excluding seafood and shellfish). While New Zealand is not big enough to rank in the worldwide charts for total meat consumption, New Zealanders are continuously ranked in the top 5 and often in the very top spot for the most meat consumed per person on average.

Between 1986 and 2006 New Zealander’s poultry consumption alone rose from 14.05kgs per person per year to 36.5kgs. On average, a New Zealander consumes over 140kgs of meat every year – more than three times the world average. We are a country that chants the mantra “it’s not a meal without meat” and although there are many important vitamins and minerals present in meat that help with general nutrition and well-being, 140kgs per year per person is well above the FAO’s minimum recommendation of 33kgs annually per person for general good health and nourishment. And it’s not just New Zealand who have an insatiable taste for flesh foods – the average amount of meat people eat on planet Earth annually grows by about 5 million tonne every year.

Certainly, the animal rights and vegetarian movements are slowly and steadily gaining increasing support for fair treatment for all species. Free range pork is now offered in most city supermarkets in the form of leg, streaky and sandwich-ready shaved. Free-range whole chickens as well as pre-packaged breasts and legs fill freezers over the country (although some companies offer both free-range and non free-range options which makes you wonder whether their motivation is ethical or monetary). Humans are waking up to the concept of treating the animals we eat with more care.

Yet so long as meat consumption numbers as big as those above continue to work against this positive stream of action, any alternative solutions to the ethical dilemma of animal suffering in factory farms should be being considered, and discussed.

Adam ShriverIn putting forward the idea that livestock animals be genetically modified to no longer feel pain, Adam Shriver cites an abundance of research to support his view that we are very close to, if not already at, the point where such animals could be bred. First, we must deal with the concept of ‘pain’, which researchers have handily pre-packaged into two distinct dimensions for easy understanding – the sensory dimension and the affective dimension, both of which correspond to activation in separate parts of the brain.

Activation of the primary and secondary somatosensory cortices is related to the sensory aspect of pain – its intensity, location and quality (i.e. whether it’s dull, sharp or burning etc.). Activation of the anterior cingulate however is related to the affective aspect of pain – how much the physical sensation bothers or discomforts us. In 1997 Rainville and colleagues successfully isolated the affective and sensory dimensions of pain and demonstrated that they could be modulated independently. They found that lesions to the primary somatosensory cortex resulted in patients who had a vague feeling of discomfort but who could not pinpoint the location or quality of the pain whereas lesions to the anterior cingulate resulted in patients who felt the pain but no longer minded it.

Several authors have argued that it is the affective dimension of pain that is relevant to what we term “suffering” – with human patients taking morphine given as an easily palatable example. Patients given morphine mimic the effects of those with anterior cingulate lesions – ie, they feel the pain, but no longer mind it so much. Unfortunately though, non-human animals can’t talk. Deciphering their experience of pain is not as easy as asking them if this or that bothers them, but researchers have thought up some pretty clever ways to measure the affective dimension of pain in nonhuman animals.

One of the most common methods used for measuring the affective dimension of pain in nonhuman animals is by using what’s called a conditioned place reference (CPP) paradigm. What it basically involves is the placement of a nonhuman animal in varying degrees of an uncomfortable environment (usually due to the presence of noxious stimuli), and comparing its preferences before and after the administration of lesions or injections that stimulate or inhibit the different dimensions of pain.

For example : rats with hypersensitive paws that are “stimulated” (i.e. hurt) in a dark room develop a preference for a light room – a preference that disappears after one administers a lesion to the anterior cingulate. The rats still withdraw their paws at the “stimulation”, but they no longer take action to avoid a situation they have come to associate in previous experiments with pain.

The micro-injecting of inhibitory neurotransmitters into the anterior cingulate at the very beginning of the experiment prevented the rats from developing any aversion in the first place. This research has evolved to the point now where specific enzymes which are essential for the affective dimension of pain can be targeted and removed, creating a “knockout” creature with a severely reduced if not completely eliminated capacity to suffer.

Shriver does identify potential constraints or problems, were livestock animals to be genetically modified in this way. One issue is that of bruising in meat. Bruised meat tends to be of a lesser quality and a deadening of the affective dimension of pain could result in a lessened ability for livestock to avoid situations where bruising occurs (if you don’t feel your toe stubbing the concrete you’re likely to continue dragging your feet).

Another issue is the fear of opening potential floodgates – so far no GM animals have been approved for human consumption. Will approving knockout livestock make it harder to disallow the genetic modification of other creatures? And could modifying animals so they don’t feel or respond to pain encourage cruelty towards them? Then of course there is the issue of how Joe Consumer is likely to feel about eating GM meat, although it can be argued that the selectively-bred, hormone injected meat we eat today is far from what God or nature intended.

From a strategic point of view, the idea of mass-producing knockout livestock for factory farming certainly makes sense. Genetically modified meat is certainly likely to get more support from the conglomerates who would be left out of pocket were vegetarianism to be the primary strategy, and such companies undoubtedly hold the ability to shape public discourse. And genetically modifying livestock is inexpensive – once you have the phenotype you can breed it over and over again.

No matter how much of a logical or ethical argument can be made for the idea, some people will be outraged at the prospect of genetically modifying livestock for human consumption. After all, doesn’t this solution miss the point a little bit? Isn’t genetically modifying knockout livestock as a means of easing our moral suffering just whacking a band-aid on top of a bullet wound?

Tom Regan – a well-known American philosopher who specialises in animal rights theory – argues that all living animals deserve the right to be treated with respect, and when we fail to do so we become morally blameworthy. Does the minimisation or elimination of livestock animal’s capacity to suffer equate to respect? Because if not, the genetic modification of livestock for factory farming could leave humans with an even heavier load on their moral conscience.

Shriver, for his part, does believe that the best way to avoid suffering in animals is to stop consuming them. But with mass vegetarianism seemingly not on the horizon, he believes it’s not a question of whether we continue to violate animals rights anymore – it’s a question of whether we’d rather violate their rights and cause them suffering, or just violate their rights.