When to cull
Quick backstory, I replaced a rooster with a hen into my total flock of 3 about Dec 16. New hen showed sickness soon after and both my remaining birds got it. Virus right? Here's the questions. When introducing Terramycin to water they seemed to get better but not all the way back, especially the new one. I stopped after 7 days because improvement was minor and not at all in the new bird, and now they are worse. Was it a bacterial thing? Can I restart antibiotic? What is the best way to go about this, should I just kill them and start over? Very squeamish about culling! Ha. Thanks for any help! First time having chickens
Yes. Antibiotics can be used again after a period of time. Consider trying a different antibiotic. I use Tetracycline with good results.
What are the bird's symptoms? Antibiotics will not work on many poultry diseases.
While a chicken is alive there is hope. I've seen many chickens appearing very ill looking normal the next day. While a vet is the best option it is not always affordable. Try a different antibiotic. Be sure it is for respiratory/intestinal infections-Ornacycline/tetracycline. Not all antibiotics are for the same problem. Good luck.