That is why the normal development of a pigeon is often closely and thoroughly examined. What came first, the chicken or the egg? Let’s start with the egg that develops inside the hen. Five days after the hen has coupled two ova are formed inside the ovary. They grow fairly quickly, depending on the ovum, until they have outgrown the ovary itself. That is when the couple starts to build a simple nest. About 44 hours before the first egg is laid the protective skin of the bulging ovum bursts open and enters the fallopian tube. This is the so called ovulation. The second ovulation takes place about 40 to 44 hours later. The first ovulation happens at 22 o’clock, followed by a night’s rest of ten hours. This is to make sure that the egg is not accidentally damaged, for instance in a fight. The fertilisation of the nucleus occurs in the first 20 hours after the ovulation; it takes place deep in the fallopian tube, close to the ovary.
In theory a pigeon’s sperm can stay alive in the hen’s genital region for two weeks. In practice, however, the last cock that fertilises the hen will be the biological father of the youngster. If you want certainty about the fatherhood you have to make sure the hen does not come into contact with any other cock for the full two weeks. If the hen has had sperm of her first partner for three or four days, the sperm has significantly diluted and weakened over that period. As a result it is no match for the fresh sperm of a new partner, which is more vital. There are exceptions of course. Sometimes the nest partner is cheated by a cock from the same loft.
Fertilisation occurs at least 24 hours before the egg is laid. Immediately after the fertilization, the nucleus starts to develop, even before the egg shell is formed. This takes place during the night and the day before the ovulation. With the help of particular motions in the fallopian tube the ovum takes a relatively long way along the genital region. Meanwhile there are three events in chronological order. In the magnum, which is the first part of the ovula, a layer of egg white is formed around the yolk. The chalaza, a special structure of egg white, holds the yolk and the nucleus in place. The egg white or albumin serves as food supply for the embryo. In the body of the uterus three parchment like membranes are formed around the shell of egg white. Their function is to offer protection. In the uterus the so called shell gland secretes the substance required for forming the eggshell. At this point the fallopian tube is approximately 50 times bigger than normal. The entire egg stays in the uterus for another 24 hours. Under the influence of the mammalian hormone Oxytocin the hen lays an egg between 4 and 6 pm. This first egg should not be brooded to prevent the embryo from developing. 24 hours later, in the early afternoon, the second egg comes out and the two partners start brooding it for 17 or 18 days. The cock sits only in the afternoon; the hen sits her eggs from the late evening until the following noon.
A freshly laid egg already contains a developing brain; by the end of the second day the heart of the embryo starts to beat. On the twelfth day you can determine the sex of the bird. Seventeen days after the egg was laid the two youngsters will hatch simultaneously. Since the second egg is laid 44 hours after the first one the first egg will not be sat in the first 44 hours. To avoid accidents you should not take pecked eggs in the hand on the seventeenth day after they were laid. The cracking sounds you can sometimes hear are caused by the young pigeon trying to crack the eggshell with its egg tooth, which sits above its beak. The widest part of the pecked egg, where the air chamber is located, is forced open with the shoulder girdle. As soon as this has happened the young pigeon can stretch its neck. At this point it takes a rest in the remaining eggshells until the blood vessel of the yolk sac detaches from the egg shell. The remaining yolk sac is then ingested into the bird’s stomach. This serves as food supply for the first few hours after the birth.
There is no other type of bird that raises its youngsters in the same way a pigeon does. The production of crop milk is caused by the hormone prolactin. This milk is a creamy substance which looks a bit like coagulated milk. The production of pigeon milk in the crop wall is caused by a gland. Eight days after the egg was laid there is a modification in the crop wall: a large number of feeding blood vessels start to form and the growth cells start to multiply. On the twelfth day the crop wall is fully developed. A layer consisting of nutrients is pushed out by the layer formed by the growth zone and new cells. The cells that are pushed out die away, detach from the crop wall and they fill up the crop. The dead cells that come from the crop wall are rich in fat and transform into crop milk. Crop milk consists of 70% water, 18% proteins, 9% fat, 2% minerals and 1% sugar and other elements. As soon as the newly born youngster is dried up and the neck has enough strength to stretch out the hen knows it is time to give her offspring a first meal.
The beak of the youngster is placed in the beak of the hen in such a way that it can suck up as much of the milk as possible in a short period of time. The crop is under tension. Both the cock and the hen produce crop milk. This sounds normal but is in fact very unusual for a bird. On the fourth day the youngsters starts eating very small seeds from the hen’s beak and on the twelfth day the cock and hen no longer produce crop milk; they feed the youngster with small seeds. The longer the youngster is fed by its parents the stronger it becomes. In its first days a young pigeon will eats its own weight in food and in the first 48 hours they double in weight. The youngster should sit quietly in its nest bowl. Restlessness indicates a lack of food or a disease and is not at all a sign of vitality. A restless youngster is not likely to become a champion. 20 to 25 days after the birth the youngster is weaned, depending on the season and the weather. We prefer youngsters that are weaned as soon as possible. After a few days the youngster will be able to eat from the feeding tray independently. The earlier they wean, the sooner they become independent.