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The good news is that it's reversible. When you stop feeding antibiotics to animals, the amount of resistance bacteria in the gut seems to reduce as well.

Additionally, good management practices (clean pens, good hygiene, low stress) and proper feed could make the use of antibiotics in animals (almost) obsolete.

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> The good news is that it's reversible.

While bacteria evolution can't be reversed, stopping antibiotics in animals can help lower the number of resistant bacteria. Good care practices can reduce the need for antibiotics.

It actually can. Bacteria reproduce and die off rapidly. That means the rates of mutation are high. If there's no selective pressure from the antibiotics, then there's nothing reinforcing that resistance and it can mutate away in a few generations. This has actually been tested in laboratory settings: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6707769/

While bacteria evolution can't be reversed, the antibiotic resistance usually have a cost to maintain (the fitness cost¹) and without the evolutive pressure cause by the antibiotic, bacteria without those costly genes will eventually dominate.

1) https://www.nature.com/articles/nrmicro2319

The latter is not really the case. There seems to be something that causes animals being fed antibiotics to gain weight faster than without, all other circumstances being equal. This might have something to do with gut flora.

While it's true they experience more weight gain, that's more of an off-label use. That doesn't negate the claim that proper procedures/care/environment could make the use of animal antibiotics more rare. There are other alternatives to increasing weight gain, although the use of any medication to induce weight gain should require careful consideration.

The off label use of "makes animals gain weight faster" is why the entire industrial animal meat industry has been feeding antibiotics to cows for over a generation now. It's why "antibiotic free" is a marketing label now, because the opposite was the previous default. The antibiotic properties of antibiotics are basically a side effect.

Eh, sort of. It's still mostly secondary. If you aren't feeding cattle antibiotic in a CAFO where they're crowded, eating spent brewers grain (mostly from fuel production), and living in filth, then they will get sick and die. Same thing for most chicken houses until changes were made a few years ago. The 10% or so of production that takes place on small farms generally didn't use antibiotics as a standard ration because they didn't need to, even if it would have slightly improved weight gain. Even the industry is try to voluntarily eliminate it in pork because they want access to international markets.

> If you aren't feeding cattle antibiotic in a CAFO where they're crowded, eating spent brewers grain (mostly from fuel production), and living in filth, then they will get sick and die

Much citation needed. I don't know exactly what you mean by CAFO when it comes to cattle, but the EU banned routine administration of antibiotics with no noticable effect on the practice of permanently housing cows or beef cattle

Plenty of citation is available if you google the term you don't know. Here's a basic overview of a CAFO (common in US, rare in EU).

https://www.sierraclub.org/grassroots-network/food-agricultu...

Thanks for the patronizing answer to a question I didn't ask

The EU has no shortage of feedlots and zero-grazed cow herds, and yet has phased out routine administration of antibiotics without any noticeable reduction in the animals in these conditions.

Therefore...

I'm asking for a citation for your claim that it's not possible to keep animals alive in these conditions without the use of antibiotics

> If you aren't feeding cattle antibiotic in a CAFO where they're crowded, eating spent brewers grain (mostly from fuel production), and living in filth, then they will get sick and die

Do you have a source?

Greater weight gain is the PRIMARY use of antibiotics on animals. There are not given to the animals because they are sick, or to ward off sickness; they are given to ALL animals in a flock/herd to increase their size and therefore their value.

Even supposing that’s true, perhaps the same effect can be achieved without antibiotics? For example maybe some kind of probiotic feed that displaces the undesirable gut flora?

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