Why are only a few of my hen's incubated eggs hatching properly?

Hi there. So sorry you are having this issue. No way to tell why she stopped sitting on them. It is a very common occurrence actually. Something may have started her or one of the other hens may have tried to bully her off of them. Those are the two most common reasons. Sometimes it is the movement starting in the eggs that startles them. Who knows....you will probably never know. She may also continue to do this behavior in the future - some are just weird like that. You are doing everything right. I can't think of anything else you should do. If you have more questions feel free to ask again! Best wishes!

You can candle the remaining eggs to see if they are fertile or viable. Chicken eggs need about 21 days incubation before chicks hatch. Fowl cholera is spread through the mucus of infected chickens and can survive for up to 3 months in the environment under optimal conditions. It is not likely the chicks will hatch already infected.

If you just added in new birds it's likely stressing your hen a bit which can disrupt laying. I would give her at least a week or two before I worry about the fact that she is not laying eggs regularly. Making sure she is on a balanced layer feed along with being given plenty of fresh water and enough nesting space (usually 2-3 birds MAX per nest box) can also help ensure she feels comfortable enough to lay. Another possibility is that she is still laying but has moved her nest to somewhere else, especially if she is free-ranged. Searching for a hidden nest, and if found, keeping her cooped for a few days may help encourage her to begin using the nesting box again.

The eggs will only hatch if they have chicks in them, ie were fertile. This would only be possible if your female was with a male. Usually the eggs should hatch after 18 full days of incubation. You should inspect the egg with the crack. The chick may be too weak to open the shell and you may have to help by opening the crack a bit. and see if the chick is still alive. If so you can open the egg more if the chick is not able to open it by itself.

This is a complicated question with no simple fix. IT is possible even though they are having mating behavior they are actually both females. Also, the male might not be able to produce appropriate sperm to make fertile eggs. Typically the eggs need certain temperatures and care to grow live birds too. I would recommend taking them to a vet for a good exam and proper sexing. hope that helps

That can be normal, yes. You can check the eggs when they are not sitting on them to see if they are viable - eggs that are fertile usually start off very translucent and then become more opaque (darker/more solid color) as the embryo develops inside. (12 days should be enough to see this change.) If the eggs don't seem viable, or the parents stop sitting on them, they can be removed. If they aren't hatched after 3-4 weeks, they are likely not viable and should be discarded. Make sure you offer an extra source of calcium for your female in the form of eggfood or a cuttlebone. This can help replenish the calcium that was used in making eggs and prevent egg-binding (an egg getting stuck) if she decides to lay more.

Thanks for your question, and it sounds like you have quite the situation going on. With that severe of a drop in egg production, I would be concerned about severe stress, nutritional deficiency, or some kind of an environmental issue. I would recommend evaluating the husbandry to see if everything is ideal. If you have had any changes in diet, with a focus on a lack of calcium, that can cause a drop in egg production for many birds. Also, if you have had any stressful events, that also can cause a short term drop in egg production. From what I can find, the stress pack should not be harmful to your chickens, but ensure that adding it to their routine doesn't cause them to not want to ingest the food/water that it is added to. I hope that gives you a place to start, and that the egg production starts to turn around very soon.