Healthy user bias in this study is used to describe the behavior that those who have negative outcomes on OC cease using OC.
Other uses of the term healthy user bias within this study:
Research on the effect of oral contraceptive (OC) use on the risk of depression shows inconsistent findings, especially in adult OC users. One possible reason for this inconsistency is the omission of women who discontinue OCs due to adverse mood effects, leading to healthy user bias.
Similar underestimation of effects can be seen in observational studies not considering previous OC use, as exemplified in the Netherlands Study of Depression and Anxiety cohort, which found that current OC use in a between-person analysis was associated with lower risk of depression, while the within-analysis showed that the time during OC use was associated with an increased risk of depression. This discrepancy is likely explained by a healthy user bias as those negatively affected by OC use had discontinued and thus represented nonusers in the between-person analysis (Morssinkhof et al., Reference Morssinkhof, Lamers, Hoogendoorn, de Wit, Riese, Giltay, van den Heuvel, Penninx and Broekman2021).
This sentence you're quoting indicates the exact opposite of what you've attributed it to.
Most children who allege to be trans are influenced by their mother.
Ok? Are atheist groups that perform this behavior better or worse? I don't understand what you're objecting to, exactly. Seems like an opinion piece.
- Chickens have been artificially selected to produce an insane amount of eggs compared to their wild ancestors. This has negative health implications. For example, they often struggle keeping their bones strong because a lot of calcium is needed for the egg shells.
Even more so today than a century ago. Feed formulations from 100 years ago list a prize leghorn (the most prolific egg layers, and what most egg laying factory farms keep) producing about 100 eggs a year. Contrast that with today's typical leghorns which produce 280 eggs a year. That's what an average leghorn today can lay. Most of that can be attributed to how good we've gotten at feeding them over the years.
However, a chicken will cease laying eggs before she begins to struggle with weak bones. Typically it's the eggshell which becomes weakened first. Or she may lay a shell-less egg. Or cease laying entirely.
This year there has been a shameful amount of people claiming that their chickens have stopped laying eggs because the feed producer is allegedly putting something in the subpar cheap feed to cease them laying. These people claim that once they put the chickens on a homemade feed-- which is often even worse than the already subpar commercial feed-- the chickens begin laying again. It's a total lack of knowledge about chicken biology and embarrassing to watch. Chickens slow or stop production of eggs naturally during the winter or during molt. They may also stop when it becomes too hot. I'm not exaggerating when I say that each individual claiming this was feeding subpar, cheap, 16% protein layer feed with no additional supplemental calcium.
Anyway I'm getting too far in the weeds. I don't particularly take issue with veganism, so I'm not trying to debate. Just offering some info.
Whoops, I screwed up some info in that post so lemme try and redeem myself.
I screwed up the chicken chromosomes... The Rooster has ZZ and the hen has ZW. When I was typing it up, I was like... "hey is this right? This is right, right?" I should have just checked...
Anyway, it's only relevant to sex link chicken breed hybrids and has practically nothing to do with a typical breed. I was just trying to demonstrate that sex links (which can be sexed reliably at day one) don't solve anything about the surplus male chicks, and only results in one generation of chicks which can be reliably sexed.
Here's a quick punnett square, I guess. The barred gene is located on the Z chromosome.
So a barred hen has ZW in this example and a solid non barred rooster has zz, just for legibility. So the males resulting from the breeding of a solid rooster to a barred hen would inherit one barred Z from the hen and one solid z from the rooster.
| Z | W | |
|---|---|---|
| z | Zz | zW |
| z | Zz | zW |
However, the resulting chicks cannot be used to produce more sex linked chickens. The female chicks have no barred Z, and the males have only one solid z. Barred to solid doesn't work as it results in all chicks being barred.
| z | W | |
|---|---|---|
| Z | Zz | ZW |
| Z | Zz | ZW |
But yeah... I mean, if it doesn't matter if you have female or male chicks, because you have purposes for both, then you don't need to sex them so quick, so you can just have a normal, sustainable breeding population.
Meat birds like cornish cross have this same problem. You can't reliably have a cornish cross through breeding cornish crosses. I mean, there's more problems with cornish crosses than that, as typically they're not able to reach breeding age, anyway. When they live much longer than their intended slaughter date, they usually have heart attacks or break their legs. It's also possible to overfeed them to weights that will crush their organs.
I got my rooster for free, and didn't end up eating him. I'm allowed to keep roosters and he does a good job looking after his flock. And, I want fertile eggs. So, not every free rooster finds himself in a cookpot.
In general, I really enjoy having chickens, and they're fun to have around. They do an excellent job keeping my property free of ticks, and they also eat maggots out of cow patties, which keeps the flies down.
Hi, I get what you mean on practically everything you're saying here. I raise chickens for meat and eggs.
Most people who keep backyard chickens are banned from having roosters at all, so I think that explains a lot of the male surplus. That's mostly HOA ridiculousness. Roosters aren't that loud imo.
Sexing chicks can be a little more reliable than that, though. For sexing chicks, there's autosexing breeds and sexlink hybrids that take advantage of the ZW male chicken chromosomes and WW of the females. For sex links, a solid color male mates a barred colored female. The males inherit one W from the females, resulting in a barred chick (white dot on head). The females have solid coloring. But, those males are subject to the various disposal methods of male chicks, as you say.
And the female chicks, having heterozygous coloration genes, can't produce reliably sexed chicks. So for my purposes I don't consider them sustainable, as I would like to be able to subsequently hatch chickens from orginal stock. I don't want to rely on hatcheries. Idk if you had seen this, but hatcheries were SLAMMED this year, with many orders of cornish cross (meat bird hybrids) being cancelled from many different hatcheries.
For autosexing breeds, it can be a bit more hit and miss. Typically they also take advantage of solid / barred genetics. Some of these include California Grey, Creme Legbar, Crele Penedesenca, Welsummers, Bielefelders, and Dorkings. But these must be very purebred (inbred) to maintain the autosexing. So... Idk. I like many of those breeds and plan on bringing some into my flock, but I also plan on eating surplus roosters.
Seeing the rooster rehoming also an irritation of mine. I feel like if people insist on not having their roosters eaten, they need to provide that home for them, themselves. Bachelor flocks are a possibility. But it's also very possible to just... allow people to eat them? But I see people rehoming roosters for $50 to prevent someone "just eating them" as though feeding someone could possibly be an ignoble end for a rooster.
Anyway for the wider discussion, I think domestic animals have a large role to play in solarpunk. Even raised for meat. I think there can definitely be a better collaborative, symbiotic relationship with animals and the earth with homereared animals.
Some hatcheries will sell the male chicks (cockerels) as meat birds instead of just culling them. But supply vastly outstrips demand...