The most common problem encountered by pigeon keeper is embryonic death. For some reasons, there have been cases in the past when more than 5% of all the eggs would not hatch because the bird embryos inside simply die. It is said that when the embryonic death rate reaches this level, pigeon keepers should act fact and immediately reassess the condition of the entire population kept in the pigeon loft or pen. It was found out that the most common reason why the death rate of the embryos reaches to this level is the presence of the salmonella virus. This virus can cause infections which are fatal to the yet undeveloped bird. Pigeon keepers should make themselves aware of the many reasons why pigeon embryos die in order to prevent further deaths. In general, embryonic deaths can happen during the three different stages of development of the pigeon. These are:
Phase 1: 2-3 days after the eggs are laid (the onset of the incubation)
Phase 2: During the 10-day growth period of the embryo (that is between the 4th and the 14th day)
Phase 3: 2-3 days before the egg hatches
The main reason why embryonic deaths happen during this stage is temperature dropdowns. Once the egg is subjected to inadequate temperatures, the embryo inside it becomes injured and after subsequent injuries, it will experience genetic problems which can lead to death. Genetic problems include anomalies that mutate the embryo into something which cannot support life. The only way to diagnose if the embryo is experiencing this mutation is through an autopsy. Pigeon owners should invest in the autopsy in order to know what the cause of the embryonic death is. This is the most viable way to know how to deal with the problem and avoid further deaths in the future.
Embryos would get injuries because of temperature changes because of their excessive sensitivity to vibrations. When the temperature is not right, the embryo inside the egg vibrates, jarring itself into the egg shell which in turn can cause the injuries. The main reason why the temperature drops is poor parenting. When the adult female pigeons prove to be incapable of incubating their own eggs, then it is imperative that the owner take the initiative and place the eggs in an incubator. Some owners do not even wait to see if the female pigeons would incubate their eggs properly; right after the eggs are laid, owners are quick to remove them from the nests and place them in an incubator to make sure that they hatch.
Embryonic deaths at this stage are primarily caused by malnutrition. The embryo needs extra nourishment during this stage because of the growth that it experiences. This is also the longest phase in the incubation process. The good news is that only a modicum fraction of all embryonic deaths happen during this stage. The main reason is probably because of the fact that the egg in itself is already capable of providing the embryo with all the nutrition that it needs. However, in cases when the egg contains less than the required amount of nutrition, then the bird would die. Unhealthy female pigeons are most likely to lay such kinds of eggs.
Nevertheless, apart from malnutrition, the embryos at this stage can also die out of infection. The cause of the infection is the bacteria commonly called as Salmonella; the other bacteria that causes the same infection is called Chlamydia. The female pigeon may be the carrier of the bacteria and hand it down to its offspring, but is some cases; the bacteria may directly infect the eggs right after they are laid. This happens when the egg shells are contaminated by anything that is a carrier of the bacteria. The first signs of infection are: appearance of fine lines on the egg surface and translucency of the egg.
The most obvious reason why embryos die right before they are hatch is the hatching process itself. This happens because the bird would have to undergo a "difficult" shift as it is being prepared to be hatched. While it is still inside the egg, it gets the air it breathes from the chorioallantois which is found inside the eggs membrane. A few days after hatching, the bird is made to breath outside the membrane without the chorioallantois. This process happens in two stages and in some cases; the birds are only able to survive the first stage.
During the first stage, the bird would have to use its small beak to prick a small hole into the egg's membrane and starts to breathe the air in this portion of the egg. After 12 to 24 hours, the little pigeon will then be able to break through the egg shell itself for its first glimpse of the outside world. The second stage would then start as the bird "drinks" the last remaining amniotic fluid inside the egg. It is during this stage when the chick gets the antibodies that it needs in order to withstand the different pathogens outside the shell. Now, some chicks would already become so exposed to the outside world before the antibodies get into their bodies and they become infected with different kinds of diseases before these antibodies can help them combat the viruses and bacteria that cause them. Thus, the chick dies before it completely gets out of the egg shell.