Backyard hens can get itchy just like other pets
AS a companion animal vet,
I work with animals whose role is to be companions for humans. This means 95% of my patients are dogs and cats, with the remaining 5% made up of rabbits, guinea pigs, gerbils, hamsters, rats, reptiles, cage birds and a few other rarities.
But what about hens? Are they companions or farm animals?
I’ve kept hens myself for the last fifteen years, and I know from experience that they fulfil both roles: they lay eggs every day, and they are valued for their produce. But they are also valued companions: if I want to have enjoyable “time out”, there’s nothing more relaxing than doing some work in the garden while the hens gather around, clucking, scraping, and having dust baths.
This double role of hens makes life complicated in some ways. The state treats hens as farm animals, which is fair enough, given that this country produces 70 million chickens for eating every year, along with an ongoing population of two million laying hens. Ireland is the highest consumer of poultry meat in the EU, and while our egg consumption is lower than many countries, most Irish people enjoy fresh eggs for breakfast from time to time.
In contrast, the number of backyard hens is tiny: there are no official figures, but I’d guess that the absolute maximum number would be 50000 hens, which would mean that these “companion animal hens” make up less than 0.1% of the nation’s hen population. It’s no wonder that they are almost completely disregarded by the State’s official bodies.
So I need to register my flock of five hens in the same way as a farmer needs to register his flock of twenty thousand chickens. And when my hens fall ill, the available licensed treatments are often only available in volumes to treat thousands of hens. If I want to treat just five birds, I could be left wasting over 95% of the medication because I just don’t have enough birds needing treatment. This can make life complicated, not just for my own hens, but for any other backyard hens that I am asked to treat.
This week, I had a health issue in my own small flock. One of the hens, named June, had become quieter than normal.
She was spending less time running around, staying in the nesting box in the daytime. And when she was out and about, I could see that the skin on her underside was pinker than normal, with some areas of feather loss. Some of her flockmates had started to peck at her from time to time, and she seemed to be spending more time pecking at herself too.
The most obvious cause of these signs is external parasites. These little creepy crawlies move into the hens’ plumage, biting their skin and feathers, or suck their blood. There are four common parasites that affect Irish hens, each one needing a different form of treatment.
The first three parasites are tiny pinpoint sized mites, the Northern Fowl Mite, the Red Mite, and the Scaly Leg Mite. These are so tiny as to be almost invisible to the naked eye: they can be seen as moving dust in the birds’ feathers in some cases, but samples from the hens may need to be examined under the microscope to completely confirm this diagnosis. We have had infestations of both of these in the past, but with rigorous measures (including power spray cleaning the henhouse) we have managed to eradicate them.
The fourth type of parasite is bigger, but still tiny: lice. These are big enough to see with the naked eye, measuring 2-4mm long, and moving slowly around the bird’s skin.
All of these external parasites cause similar signs: feather loss, reddened skin, and general ill thrift: affected birds then to become quieter, losing weight, lacking energy, and slowing down. If left untreated, the parasites can even cause death.
For this reason, regular plumage checks on any birds that seen under the weather are important. It is important to check under the hen’s tail, around the legs, and under the wings, looking for damaged skin and feathers, small moving bugs, and collecting samples to examine under the microscope if needed.
So I picked June up, and gave her a thorough check over. The diagnosis was easy: I could see dozens of lice, crawling slowly around her skin, hiding beneath her feathers.
This was a mystery: where could these lice have come from? We bought our hens over a year ago at a poultry fair, and there have been no new birds. Yet there have been no signs of lice up till now.
Lice spend their entire lives on the birds, from egg to nymph to adult. Their life cycle is about 4-5 weeks, and they can only survive off the host for about 1 week off the bird. So there are two possibilities: lice could have been lurking in low numbers on our hens since the beginning (but I’ve checked them on many occasions and never seen them). More likely, lice could have invaded our garden in the plumage of wild birds, hopping onto the hens from a fly by night visitor.
The good news is that once the diagnosis has been made, treatment is simple. It’s likely that all of our hens would have lice, because they spend time huddled together at night, so I gave them all an anti-parasite treatment, to be repeated in a few weeks.
And since there are only five hens, there is plenty left in the packet for me to do this!