Disease Screening Guide
Chicken Disease Testing Explained
What PCR screening detects, when it is worth running, and how to read the result.
Disease PCR looks for a specific pathogen’s genetic material in a sample from your bird. Unlike a visual diagnosis or a guess based on symptoms, it names the organism. That is what you need before you buy medication, cull, or bring new birds into a flock.
A PCR result is laboratory information, not veterinary treatment advice. It tells you what is present. Your vet decides what to do about it, and a positive on a reportable disease should go to your state veterinarian.
🧬 What we screen for
| Pathogen | Why people test | Typical sample |
| Marek’s disease virus | Sudden paralysis, wasting, unexplained young bird deaths, or checking new stock | Feather shaft or blood |
| Mycoplasma gallisepticum | Chronic respiratory rattle, swollen eyes, bubbly eye, sneezing that never fully clears | Choanal or oral swab |
| Mycoplasma synoviae | Lameness, swollen hocks, respiratory signs | Choanal or oral swab |
| Salmonella | Flock health screening, hatching egg sales, unexplained chick losses | Cloacal swab |
Disease screening is currently available for chickens. Swab collection instructions walk through oral, choanal, and cloacal sampling.
⚠️ When it is worth running
- Before adding birds to your flock. The single most common reason people wish they had tested. A carrier can look completely healthy and still infect everything you own.
- Respiratory signs that keep coming back. Mycoplasma does not resolve on its own and does not respond to guessing at antibiotics.
- Unexplained deaths in young birds. Marek’s is common and often mistaken for injury or a nutrition problem.
- Selling hatching eggs, chicks, or breeding stock. Screening your breeders is what serious buyers ask about.
- Rehoming or exhibition. Shows and many rescues want a clean screen first.
📋 Reading your result
| Result | What it means |
| Not detected | The pathogen’s genetic material was not found in that sample from that bird on that day. It is not a lifetime clearance, and a bird sampled too early can test negative |
| Detected | That pathogen is present in that bird. It does not by itself tell you how sick the bird is or will get. This is the point to involve your vet |
Testing one bird tells you about one bird. For a flock question, sample several birds, and prioritize the ones showing signs plus a couple that look fine, since carriers are usually the ones that look fine.
⏳ Practical details
Swabs go back to us in a plain envelope. There is no kit to buy or wait for. Turnaround is 2 to 3 business days from the day your samples arrive at the lab, results load into your Pullidex account, and samples are held for one week after testing.