Before introducing new birds to an established flock, they should be quarantined. You will also have to quarantine chickens that have fallen ill or shows signs of illness.
The reason for separating new birds from the established flock is eight parts sensible to two parts paranoia. If you source the new chickens from a reputable supplier or have hatched the birds yourself, there is little chance of the birds harboring illnesses. However, the potential problems you are guarding against are not easy to spot. Chickens may have internal or external parasites, or the bacteria and viruses that cause disease may be lurking out of sight.
Quarantine significantly lowers the risk of the new chickens spreading parasites or infection in your established flock. In the age of Covid-19, the idea of quarantining has negative associations with isolation and inconvenience. With new chickens, all you’re doing is giving them some space away from the main flock. Other than that, it’s chicken business as usual!
What is quarantine, and when should I quarantine my flock?
Quarantine simply means separating one or more chickens from the rest of the flock. The aim is to minimize the danger of illness spreading between ill and/or new chickens and the existing flock.
All new birds should be put into quarantine. Chickens bought at a show or fair will have been in close proximity with lots of other birds. Chickens from reputable suppliers are not immune to disease either, and even a new-hatched chick may harbor illness, as certain bacteria can penetrate eggshells and infect unhatched birds.
Why do chickens need quarantining?
Bird diseases and parasites spread quickly, and by the time you spot the symptoms, it’s often too late to prevent the other chickens from falling ill. Stressed birds are particularly prone to illness, and a new hen will always be a stressed hen. There’s nothing you can do about this, as it’s a symptom of moving from the world she knew previously to the world of your backyard chickens.
A bird that falls ill needs isolating from the rest of the flock to minimize the risk of the illness spreading. If the issue is parasites – lice, fleas or worms – by the time you spot the problem it will probably be present in every bird, so in these cases, you need to buy the appropriate parasite treatment rather than quarantining single birds.
How long do new chickens need to be quarantined?
New birds should be quarantined for at least four weeks. If there are any illnesses, they will show in the first week, following the stress associated with the move. Give the new birds a thorough health check every few days.
In the final week of quarantine, keepers with a larger existing flock often introduce an older bird – perhaps one that has stopped laying – into the quarantine shed. If at the end of this week the introduced hen is healthy, all is well. If there is any disease lurking unseen, the older bird will begin to look unwell. This is the so-called ‘Canary in the mine’ method, and not everyone will be happy putting an older bird at risk. However, the main point is that you are 90% sure that there is no problem in the quarantined flock by this stage.
Note: bird flu, or avian influenza, has an incubation period of around 21 days, so a hen that was infected on the day you brought her home will not show symptoms for three weeks. This is one of the reasons why the quarantine period is so long.
Setting up a quarantine area for new chickens
There is a simple checklist that gives the quarantine the best chance of being successful:
1. Give the new birds a physical check, looking for signs of lice or fleas. Check the consistency of their droppings and their general posture, referring to our guide to healthy chickens for reference.
2. Make sure the enclosure and coop have everything the new birds need, including a roosting perch, an egg-laying box, fresh food and water, and shelter from the elements.
3. Ensure that no feathers, sawdust, dander, food or water from the quarantined new birds enter the main flock’s enclosure.
4. Don’t wear the same shoes and clothes when tending the healthy and the ill birds. Infection can spread quickly, especially on your hands and the soles of your shoes.
5. The new birds should be kept as far from the other chickens as possible. Ideally, they should be at least 10 metres (33 feet) from the main flock, and downwind as much as possible. However, this will not always be practical, and simply keeping the new chickens in a separate enclosure will be as far as many owners can go. If there is an enclosed building to keep them in, that’s perfect. Keeping the new birds upwind of the existing flock is even more important in these close-proximity set-ups.
What to do if the quarantined chickens fall ill
If any of the new birds become ill, you will need to identify the illness. If you are uncertain, call in expert help to assist with the diagnosis. Depending on the problem, the new chickens will need to be treated and isolated for another month or so. If the illness turns out to be avian flu or another lethal disease, the birds will have to be culled. In the case of the bird flu, check out our bird flu article for the latest advice.
Quarantine of new hens is a better-safe-than-sorry routine that ensures health and happiness in your ever-changing flock of chickens. It also has the advantage of acclimating newcomers to the sights and sounds of your garden before they mingle with the existing flock.