Invertebrate Welfare — April 2020
I hope you’re staying safe through the ongoing pandemic. Here’s the latest news on insect and invertebrate welfare.
Insect Abundance
A meta-analysis of 166 surveys of insect abundance provides nuance to the ongoing insect declines.
The study found that since the 1980s, there has been an average decline of terrestrial insects of around 9% per decade, but an increase in aquatic insects of around 11% per decade
Crustacean Welfare
Crustacean Compassion is seeking proposals for a research consultant to produce a report on the state of the crustacean farming and harvesting industries.
Farmed shrimp have suffered from massive bouts of an early mortality syndrome caused by a bacterial infection (referred to as acute hepatopancreatic necrosis syndrome or AHNS).
The mortality rate from these infections on some farms has been as high as 100%.
Decreasing this mortality rate would decrease the total number of shrimp raised on farms.
A new study has found that replacing fishmeal and fish oil in shrimp’s diets with algal oil and a plant feed significantly reduces early mortality syndrome in shrimp. So, if this feeding approach becomes widespread, there would likely be an effect on fishmeal production, decreasing the number of fish farmed globally.
(lightly) Diving into the economics of raising insects as livestock feed
I’ve been exploring the growing industry developing large-scale insect farming for livestock feed in North America and Europe. There seems to be extensive venture capital interest in this space, and several farms that produce insects for human consumption have pivoted to producing insects for animal feed over the last few years.
This raises an interesting question — why would it be advantageous to feed livestock insects instead of soy (the usual crop insects are proposed as a replacement for)? The answer is ultimately that it may be cheaper to feed some animals, especially chickens and fish, insects instead of at least some grain feed or fishmeal. Additionally, some farms also tout potential animal welfare benefits for livestock from eating insects.
It was counterintuitive to me that insect farming could be a cheaper source of animal feed than plants. This was especially strange after surveying insect farmers in the US, and finding that the most common food fed to crickets, for example, is commercial chicken feed (soy and corn). This question doesn’t seem to have come up explicitly in the literature, which I found odd, but I’ve found some reasons to believe that raising insects as animal feed could be cheaper in the long run than feeding animals soy.
Feed efficiency and protein content
Insect feeds are very high in protein (35% to 50% crude protein, depending on the insect). Insects also convert feed to protein at an incredibly efficient rate, in part because they are cold-blooded, and don’t expend energy regulating body temperature
The grain feed conversion rate (how much feed has to be consumed to gain a unit of body mass) for crickets is around 1.7. For chickens it is 2.5, and for cattle it is 10
It might be the case that due to this higher protein content, eating crickets provides an improved feed conversion rate.
For example, if a cow eating grain converts feed mass to body mass at a 10:1 ratio, but cricket mass to body mass at an 8.7:1 or better ratio, from an energy standpoint it would be more efficient to feed crickets grains, and then feed crickets to cows. I haven’t seen evidence of the gains from feeding insects to livestock being this extreme, but there is some belief among the insect farming community that there would be some improvement in feed conversion rates if livestock ate insects
Relatedly, when you grow a cricket, you get an entirely edible product, but when you grow a chicken, you have to grow bones, organs, etc, which aren’t edible. It might be the case that consuming crickets specifically improves the feed conversion efficiency of growing the parts of animals that are eaten (muscles)
Insects are incredibly efficient at converting grains into proteins. A producer claims that farming black soldier fly larvae produces over 1,000 times as much protein per acre of farmland than soy, and many thousands times as many as animal proteins
Yield increase
Some insect farmers claim that feeding livestock insects produces higher yields
I’d guess this is either because changing feed increases growth rates, or because insects are just better nutritionally for some animals (especially chickens and fish).
A Rwandan startup claims that their product improves poultry yields by 3.9%, and is cheaper than other animal feeds by up to 20%.
These claims all come from the industry, and are hard to verify, but if true, they would represent enormous cost-savings for a very low-margin industry.
Insects don’t have to eat feed
Insects can be raised on waste products, which are potentially cheaper than grains, or free.
One startup told me in an interview that they could produce cheaper animal feed by simply offering local breweries free waste removal of their brewing grains. They used this waste to feed black soldier fly larvae, which they plan on selling as animal feed
It is unclear how scalable this approach is
Replacing other animal-based feeds
Chickens, fish, piglets, and other livestock are fed fishmeal, which requires rearing or catching wild fish
It might be the case that raising insects is simply cheaper than acquiring fishmeal
Some startups are exploring using insects, especially black soldier fly larvae and mealworms, as an alternative to fishmeal
And, ironically, feeding insects to chickens and possibly fish might improve chicken and fish welfare on farms. One study released this year found welfare benefits for laying hens from a diet of black soldier fly larvae. This claim that insects could improve animal welfare seems potentially reasonable since many species of farmed fish and chickens eat a wide range of insects in the wild, and the grain and fishmeal diets they are fed today are likely well outside their “natural” diets.
Insects raised for food were in the news this month as the EU approved serving insects for human consumption following a long period of lobbying from industry groups. The biggest priority for US and European insect farming industry groups is getting approval to feed insects to livestock raised for human consumption.
In the US and Europe, insects for direct human consumption have not proven that they can break out of being a novelty food item. But if the economics work out in their favor, the industry may shift toward raising insects for livestock, a worrying prospect for insect advocates.
Further Research on Sea Lice
Phys.org released a news article on the ethics of using cleaner fish to treat sea lice on salmon
Quote: “...Is it right or wrong to sacrifice 50-60 million cleaner fish in order to give salmon a better life?" asks Edgar Brun, department head at the Norwegian Veterinary Institute, in a recent article in the Norwegian newspaper Dagens Næringsliv.
Miscellaneous
China produces ¼ of the world’s honey. Its bee farmers are apparently primarily itinerant, and the lockdowns due to the COVID-19 pandemic have resulted in large losses for the industry