Black nostrils, head shaking & gaping

[clucking hell]

Hi, I've had my chickens 3 weeks today. They're ex commercial free range hens around 18 months old. We were advised to work them as soon as they arrived so I did that last week using Marriages pellets with flubenvet 5kg bag for 5 hens.
I also spotted lice on one hen so I treated them all with Ivermectin.
But they still seem a bit poorly to me. One hen makes a gurgly sound when breathing.
Another hen has black nostrils and gapes occasionally. I've noticed a couple of others seem to be getting black nostrils too and one looked a bit purplish at the end of her comb

They're all eating well. We were getting some soft shelled eggs, but haven't this week. We average about 3 eggs a day.
So I've been giving them antibiotics for the past 2 days and intend to give 5 days in total.
Does this sound like a reasonable course of action? Is there anything else I should be doing? They're drinking and eating.
Should I be seeing improvements by now?

 

[azygous]

You've treated your chickens with two different worming meds, do you realize that? I don't know if that has any connection to the black nares and gaping beaks, but if they have worms, the worms are likely toast.

Without a photo of the black nares, I can't comment on what it could signify. But sometimes worming causes shock when a heavy worm load clogs the system. You could treat for shock as a start. Give the hens electrolytes such as Gatoraid or mix your own solution with one cup of water and a teaspoon of sugar and a quarter teaspoon pf salt and baking soda.

Have you checked their crops? If an obstruction is occurring due to dying worms obstructing the intestines, the crops may start to back up. That would be a sign that you also need to treat for an obstruction with oil such as coconut oil giving orally.

 

[clucking hell]

You've treated your chickens with two different worming meds, do you realize that? I don't know if that has any connection to the black nares and gaping beaks, but if they have worms, the worms are likely toast.

Without a photo of the black nares, I can't comment on what it could signify. But sometimes worming causes shock when a heavy worm load clogs the system. You could treat for shock as a start. Give the hens electrolytes such as Gatoraid or mix your own solution with one cup of water and a teaspoon of sugar and a quarter teaspoon pf salt and baking soda.

Have you checked their crops? If an obstruction is occurring due to dying worms obstructing the intestines, the crops may start to back up. That would be a sign that you also need to treat for an obstruction with oil such as coconut oil giving orally.

From what I understand ivermectin treats for roundworm well but not all chicken worms so you still need to do the flubenvet treatment. I'm going to keep an eye on them for now. The gurgly chicken doesn't sound as bad now, but will listen again tonight. Haven't seen anymore gaping and still need to catch a chicken to wipe nostrils with damp cloth and check it's not just dirt. I'll check crops tonight too. Thanks for the reply.