Knowing your chicken and its behavior will help you spot problems early on. You should really handle your chicken every week and check it over for injury and mites. Disclaimer: I am no expert, the following is what I personally do, but I accept no responsibility if you follow it.
Chickens have one exit point called the vent. | This link show how eggs and droppings are separated within the chicken so that eggs are sterile when layed. | This link shows the flight feathers in a chicken. There are primary and secondary flight feathers, the former which will need to be trimmed on one wing to unbalance the chicken in flight and reduce the possibility of escape. Chickens with full flight feathers can fly up to 5 or 6 feet, the hight increasing as the weight of chicken decreases down to bantams. The crown/crest and wattles become redder as the chicken matures, if they are pale it could be down to illness. The legs of a chicken turn from yellow to white as she matures and can be an indicator, along with crest colour of when she will lay an egg. The body becomes less slim and fills out, and the hips widen so the legs may seem slightly further apart. The chicken starts to squat shortly before laying.
Very small red mites, or northern mites can live in crevices in the chicken house and come out at night to feed on your chicken. Mites can be found in the feathers, or sometimes on the legs manifesting in scaly legs. usually they are only found at night underneath wooden roosting bars, if you wipe the underneath of the bars and see streaks this indicates blood from mites. They can be treated with powder on the chicken and roosting area, and Microshield poultry shield is a cleaner which erradicates mites and can be used as a preventative measure. I use diatom pressed onto the ends of the roosting bars which is natural and works by breaking parasites open on a cellular level.
Lice if present can be found under the feathers crawling on the skin. Poultry shield as with mites can help prevent parasites. Lice can be treated with powder on the chicken and roosting area. We have used lice/mite powder, diatom and deosect which we made into a spray, just follow the directions. We found the spray easiest but treatment is very unpopular with the chickens. You can treat at intervals to prevent lice, or check regularly for organgy brown creatures crawling around if you separate the feathers. Lice can live around the eyes, around the vent, under the wings in particular. You need to treat very thoroughly on the skin at the base of the feathers. There is a 14 days wait between treatments of deosect. Trinny had scraggly tail feathers when she had lice, so scraggly/missing feathers is a good indicator. Chickens can catch lice from wild birds.
Worming every six months prevents a large number of potential worms species infesting your beloved chicken. In gapeworm the chicken opens their beak wide as gasping for breath. I play cautious and worm early when I have seen this, although hard to say if actually gapeworm or stretching their beak. Flubenvet powder can be mixed in with their food every six months, or even 3 months for 7 consecutive days. It can also be mixed into treats and fed to individual chickens, or mixed with a little water and syringed down the throat to make sure the chickens get the dose. Verm X is a herbal wormer given for a few days as pellets mixed with the food,or in the water, but is much more expensive. With Verm X and flubenvet, eggs can be eaten through treatment.
Panacur is given to cats/dogs and has a withdrawal period, but is not technically licensed for chickens in the UK. It may be prescribed by a vet, 4ml of the 2.5% suspension is syringed down the throat. Note if you syringe incorrectly you can get the airpipe and effectively drown the chicken. We’ve found you can add drops to the beak and the chicken drinks it, or you can add to a favourite food. Chickens should not stay on the same area of ground for longer than a year (spread of disease) unless there is covering on the floor that can be changed e.g. wood chips, which are better than bark chips which go mouldy. Some people use aubiose-a horse bedding.
Garlic, apple cider vinegar and diatom are also suggested to help with worms/internal parasites. You could also get a worm count to see if worming is successful, if there may be a worms problem, or to see if treatment is needed if you would like to avoid worming. It can cost £40 a sample though.
The loss of a nail or a minor scrape may happen e.g. if introducing new hens and the pecking order is disturbed an antiseptic e.g. teatree oil can be applied. Wound powder, (or even flour!) can be used to stem bleeding. We found blood from the vent which the vet advised was probably from straining to lay a soft egg. remove blood from injured chickens as it can encourage pecking/cannibalism from other chickens. Anti-peck spray may be needed.
The crop is part of the digestive system and forms a bump on the chickens chest when the chicken has been eating food all day, if blocked the lump will be present in the morning. Hay or long grass is a classic trigger for this. massaging it/dropping oil down the chicken’s throat/visiting a vet may be needed. You can feed bread soaked in cooking oil as it is easier than putting down the chicken’s throat. We took Trinny to the vet and they fed her water to soften it. They said using a tube to empty the crop could cause diahorrhea, which is recommended by some people, an operation may be needed if the crop does not go down. Trinny had some stretchy material tied around her front to put pressure on the crop.
Geels like a balloon full of water. This can be caused by the chicken just having had a big drink, or the crop not emptying. It may be from a distended crop where the crop is stretched irreversibly. The chicken may also have weak muscles and be prone to crop problems.
Sometimes an egg may not be laid and remain in the chicken. The chicken may hunch up, walk funny, perhaps look like they are straining. I’m sure Katy’s eyes watered a bit too. Soft eggs can be harder to lay as they don’t just slide out. You can hold the chicken over steam (not too close) to warm the muscles and help pass the egg. It should be for about 20 minutes and repeated if it doesn’t work, but I’ve not lasted that long.
I find you need to get a kettle of water ready, get the chicken in position over a bowl, wrap with a towel, add boiling water, find a point that is warm but not too hot (as judged by my hand holding chicken). Lower as the water cools, and replace if it cools too much.
The chicken may also take a few weeks or months to start laying from the point of lay stage. Short daylight hours in winter, illness (commonly worms or lice/mites), and moulting can stop egg production. Young chickens may also lay smaller eggs than normal. Chicken’s eggs increase in size over the year after the Winter break.
Chicken can often get soft eggs where there is a lack of calcium in the diet, or it is not absorbed. Shellstim (commercial supplements) can be added to the water, but not indefinately as it affects absorption. Eggshells can be baked in the oven, cooled, crushed and mixed with the food. Apple cider vinegar is also thought to increase calcium absorption. Vets can also give a calcium injection, presumably if the above don’t work. We’ve found shellstim to work after a few days.