I think it is the distinction between "livestock" and "pets".

I would also be very surprised if any vets ever managed to treat a hen successfully. They tend to hide any illness until very sick.

> I would also be very surprised if any vets ever managed to treat a hen successfully.

I know for a fact it is possible. I am acquainted with veterinaries and have kept chickens temporarily while they were recuperating.

> They tend to hide any illness until very sick.

Indeed. So do rabbits and other “exotic” pets. It does make treatment harder, but experienced people tend to develop a sense to notice it sooner. You yourself have probably already developed that skill to some extent and might be able to identify “strange” behaviour is specific individual chickens.

My neighbor‘s dog bit one of our chickens. We ended up taking her to the vet and got some antibiotics. she made a full recovery.

And yes, there’s a bit of the mix of pets and livestock. We only have five hens, and they all have names. If you’re naming your animal, is it a pet?

Our hen was treated successfully, but it wasn't for a sickness, in this case it was an injury:

She somehow got one of her talons very loose and it ripped off, naturally becoming infected. The treatment was antibiotics and later full amputation of the toe in question + chicken house rest. She's still living happily, but would've died without treatment. Overall, it was a surprisingly cheap treatment ($130CAD?)

Really? I have taken chickens to the vet twice (in 8 years).

First was one taken by a fox. My wife chased the fox and he dropped the chicken (she was too heavy for him). She had a broken leg and a broken wing. Both perfectly treatable and she went on to make a full recovery, resumed laying. As result of her closer contact with people during her recuperation she became very tame and socialized with visitors on the deck in the evening. Arguable she became a pet after her vet treatment.

Second was one with an eye infection (eyelids swollen so she couldn't see). She also made a full recovery.

I don't take every sick chicken to the vet, but if you've kept chickens for long enough you get an idea when it's likely to be mworthwhile (it's never financially worthwhilte). What's worthwhile will vary according to what you can afford and how you relate to your flock generally, the age and health of the hen and likelihood of recovery.