When a hen breeds

When the hen becomes a mother hen

The hen lies in her nesting place, a small shuttlecock digs into the daylight under her feathers. Take a few steps, look around curiously. And then disappears again under the protective wings of his mother. What reads so idyllically can unfortunately only seldom be observed today with the chickens. Most hens do not see their young growing up. There is no way you can help them choose what to eat, show them where to run or protect them from the cold. Today, most of the tens of millions of chickens around the world are incubated in an incubator and raised in special chick shelters.

For the chickens in the wild, broodiness is still vital for survival. Without them there would be no offspring and the species would become extinct. In commercial poultry breeding, on the other hand, broodiness is perceived as a nuisance. Because the hens do not lay eggs during this time. Therefore one has tried again and again to breed away the broodiness. With very good success if the breed continued to be bred.

The desire to brood increases when it is hot
When crossing different breeds, however, brooding hens could again and again be observed. As described in Alfred Mehner's textbook on poultry breeding, the former director of the Federal Research Institute for Small Animal Breeding, it is assumed that several genes are responsible for broodiness. It is therefore an extremely complex mechanism that is not simply inherited.

When and whether hens start breeding varies greatly and depends on the animal itself, the breed and external conditions. Some hens start hatching as soon as a dozen eggs are in their nest. Others only feel the breeding instinct in their second or even third year of life. Since chickens rarely reach this age, it is often wrongly assumed that these animals have completely lost their breeding instinct. According to Mehner, German chicken performance tests show that even a relatively high percentage of the high-performance leghorn animals, known as a breed with very little brood instinct, become broody. However, they are only brief.

The Orpington, silkie or dwarf Cochin are especially known for their desire to breed. The weather also has an influence on the broodiness. Hot, humid conditions favor the desire to brood as well as the darkness. Leaving it there or collecting several eggs can also have a stimulating effect. When you think of brooding, you might think of a hen, but that doesn't necessarily have to be the case. So-called capons, castrated roosters, can also become broody.

The broodiness is comparable to pregnancy in humans. Hens also go through a number of changes during this time. This not only increases the prolactin content of the thyroid, but also the body temperature of the animals. Although their body temperature rises only slightly, they still feel significantly warmer. The so-called brood spot appears on the abdomen. Due to the strong blood circulation at this point, the skin appears reddish and no longer has any feathers. The hen feels the greater body heat and sits on the eggs to cool down. In order to have the cooling sides under her body again and again, she turns the eggs.

Brooding hens give the impression that they would like to be alone. They eat, scratch or have fun in the dust bath very intensively, but alone and usually only once a day. If a higher-ranking hen arrives, it will quickly leave its location. A brooding hen also evades the rooster whenever possible. This isolation from herd members can cause some inconvenience. After three weeks of incubation, it is quite possible that her coop mates no longer recognize the hen and that she has to face new battles for ranking.

Some hens start hatching when there are eggs in the nest.
Image: Fabienne Schenkel

Chickens sit in the made nest
Even before the hen begins to sit firmly on the nest, she makes her typical chuckling noises. Hens are not picky about their breeding place. Since they do not collect the nesting material themselves, they are not allowed to be either. They usually decide in favor of the laying nest or look for another, well-equipped place in the barn or in the run that they think is suitable. By sliding back and forth on the nesting material, they only improve the shape of the nest. Every now and then they take a straw in their beak or peck in the nesting material. But one cannot speak of building a nest. In the vicinity of the nesting site, the brooding hens show a great willingness to fight, which, however, decreases the further they move away from it.

A broody hen shows changes not only in her behavior, during this time there are also some physical differences. For example her metabolism. The hen then only eats and defecates once a day. In comparison, hens that are laying lay their feces about six times an hour. So if laying hens were to eat just as little as brooding hens, they would lose weight and lay significantly fewer eggs. The mother hen lose about 15 percent of their weight during brood. However, once the breeding season is over, they will have made up for this loss within a month.

The broodiness can be induced by artificial prolactin supply. The prerequisites for this to work are a temperature of over 27 degrees, the hen has to find enough eggs in her nest and be in a darkened room. The generous feeding of grain is also held in breeding circles as a trigger factor for the brood. However, this is not possible with all breeds, because with some of the chicks have not been reared in the natural brood for several generations and with them the breeding instinct is therefore practically non-existent today.