Thursday, December 06, 2012

Breeding happier animals: no futuristic tech required


[Cross-posted from Overcoming Bias; edited to remove tactless commentary 2017. Also, the possibility of reducing the misery in factory farming through genetic alteration discussed in this post does not and would not justify factory farming.]
I have spoken with a lot of people who are enthusiastic about the possibility that advanced genetic engineering technologies will improve animal welfare.

But would it really take radical new technologies to produce genetics reducing animal suffering? 

Modern animal breeding is able to shape almost any quantitative trait with significant heritable variation in a population. One carefully measures the trait in different animals, and selects sperm for the next generation on that basis. So far this has not been done to reduce animals' capacity for pain, or to increase their capacity for pleasure, but it has been applied to great effect elsewhere.

One could test varied behavioral measures of fear response, and physiological measures like cortisol levels, and select for them. As long as the measurements in aggregate tracked one's conception of animal welfare closely enough, breeders could generate increases in farmed animal welfare, potentially initially at low marginal cost in other traits.

Just how powerful are ordinary animal breeding techniques? Consider cattle:
In 1942, when my father was born, the average dairy cow produced less than 5,000 pounds of milk in its lifetime. Now, the average cow produces over 21,000 pounds of milk. At the same time, the number of dairy cows has decreased from a high of 25 million around the end of World War II to fewer than nine million today. This is an indisputable environmental win as fewer cows create less methane, a potent greenhouse gas, and require less land.
 Wired has an impressive chart of turkey weight over time:

New_sweet_chart
Anderson, who has bred the birds for 26 years, said the key technical advance was artificial insemination, which came into widespread use in the 1960s, right around the time that turkey size starts to skyrocket...
This process, compounded over dozens of generations, has yielded turkeys with genes that make them very big. In one study in the journal Poultry Science, turkeys genetically representative of old birds from 1966 and modern turkeys were each fed the exact same old-school diet. The 2003 birds grew to 39 pounds while the legacy birds only made it to 21 pounds. Other researchers have estimated that 90 percent of the changes in turkey size are genetic.
Moreover, breeders are able to improve complex weighted mixtures of diverse traits:

The bull market (heh) can be reduced to one key statistic, lifetime net merit, though there are many nuances that the single number cannot capture. Net merit denotes the likely additive value of a bull's genetics. The number is actually denominated in dollars because it is an estimate of how much a bull's genetic material will likely improve the revenue from a given cow. A very complicated equation weights all of the factors that go into dairy breeding and -- voila -- you come out with this single number. For example, a bull that could help a cow make an extra 1000 pounds of milk over her lifetime only gets an increase of $1 in net merit while a bull who will help that same cow produce a pound more protein will get $3.41 more in net merit. An increase of a single month of predicted productive life yields $35 more.
No futuristic technologies are needed to make progress, although they would expedite the process: just feed accurate enough measurements of animal welfare into the net merit equation and similar progress could begin on the new trait.

4 comments:

  1. The crux of the argument, which I feel you don't really establish, is that one can select for less pain/fear. It's very clear that one can breed bigger/more productive farm animals, but not at all clear that one can do the same for pain/fear. Have you any evidence for this claim?

    This is a very interesting topic, and I'd like to see more on it.

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  2. What level of pain reduction would make it morally ok to eat meat though? Even if the animal is unable to feel pain at all you are still depriving it of life for taste or convinince. Neither of these factors hold any moral weight. Aswell as this the environmental impact of livestock would not be mitigated by this endeavour. So even with significant changes in the animals ability to feel pain vitro meat or veganism is still by far a much more tenable position.

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  3. Anonymous,

    This post wasn't arguing that eating meat would be good, it was pointing out that biological changes along the lines David Pearce suggests are possible with more prosaic technology, which would at least reduce the pain and fear involved.

    If this sort of thing were done, classify it with cage-free campaigns or selecting broiler chickens that get fewer leg injuries, not with animal product substitutes or veganism.

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  4. Looking back, I think the framing of the post was tactless and distracting, and I have edited it to just leave the substantive point.

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