- Jun 10, 2018
As breed birds – this question can have especially leisure character, and can be dictated by quite pragmatic purposes. Owners of domestic birds surely face this problem. Especially relevant this subject becomes for those who decided to get the birds who are on the semi-free contents. Most often in such mode domestic pigeons , sometimes geese and ducks get divorced
Особенности reproductive system of birds
Birds diclinous . Bodies of reproduction at males are presented by two testicles located in belly area. They are connected by semyaprovodnik to a foul place.
At females bodies of reproduction are presented by one ovary located in the left part of a body. From this rule there are exceptions: females of some species of parrots and birds of prey can have also the right ovary.
Despite complexity of the building, high intellectual level and ability to maintain high temperature of a body, birds have no external genitals though pairing at them internal.
The majority of birds provide internal fertilization with pressing of an opening of a foul place of a male to a foul place of a female. At this moment there is a sperm injection. Such process demands development of a large amount of sperm and aggression of behavior of a male who has to provide immovability of a female. Otherwise sexual intercourse can take place, but there will be no fertilization.
But in the course of evolution and at birds similarity of genitalia begin to be formed. For example, at strausoobrazny, guseobrazny, kuroobrazny males the sovokupitelny body departs from a wall of a foul place. When such birds copulate, this body moves forward and located in a foul place of a female.
Sexual dimorphism and behavior
At birds sexual selection is well developed, and it is shown differently.
Difficult rituals which allow females to choose a male from the general crowd of applicants for creation of family. the Ritual behavior connected with sexual selection can be divided into 2 parts: duels and courtings.
Duels are oppositions of males in full view of females. Such rituals can be shown in the form of fights, dances which actually represent imitation of duels, tokovaniye, that is dances with voice maintenance.
Courtings are shown in the most different way. For example, cooing and dance of a pigeon before a female. The right to make family is acquired by the most persistent and vigorous dancer. Demonstrations of a tail at a peacock, rough stickings of crowd of sparrows to a female when they as younger school students, push and poklevyvat a female until she does not choose somebody belong to the category of courting. Vorobyikh, of course, are more pragmatic, than females of peacocks . It is better to have in husbands of the vigorous and energetic impudent fellow for bringing up of posterity, than the decorated peacock hardly bearing the huge tail.
Bright coloring which gives the chance to females to choose males as clothes in department store. Colouring as means of sexual selection works only if this bird species has a sexual dimorphism. Peacocks, ducks, orioles, hens, black grouses, wood-grouses, pheasants can carry out such selection. And here parrots cannot select males on coloring – all of them are brightly painted. This coloring performs function of identification of members of the pack. Pigeons so sexual selection at that and others happens through ritual behavior have no sexual dimorphism and. Just females behave as females, and males – as males.
Special sound communications. each bird has usual sound signals serving, for example, for a danger warning or gathering of fellows in pack. However there is also a song as ritual sound behavior. Even those birds who cannot do it sing. The crow has the marriage song and sorok. Pigeons cannot shout at all, they only sing, that is coo. And the woodpeckers deprived even of such ability to singing are able to play on a wood shchepochka, managing to extend a marriage drumbeat.
There are birds whom evolution did not offend by voice. They and are called – choristers. are not necessary to the Nightingale bright clothes and complex dances . It is enough to it to sing many hours in a row, informing other males that this nested territory is occupied. On such groom with the ready apartment there will always be brides.
Over birds evolution worked thoroughly, having created a set of views with difficult behavior. The sexual selection is more difficult and more various, the more there are types which can adapt to special conditions of the environment or to become cosmopolitans with a wide range of adaptive reactions. There is also a regularity of an opposite direction: the more types, the competition is stronger, so, sexual selection is more difficult.
Postponement of eggs
During evolution from reptiles 2 directions of development – mammals and birds were formed. So the era of warm-blooded animals who could fill the being empty ecological niches began. However some of them passed to live birth, and others and inherited from the ancestors reproduction by means of eggs. Why so it turned out?
the Baby bird in egg actually continues pre-natal development. It creates the mass of risks. The best protection for a cub is a stay in mother's womb. Egg in a nest even under protection of parents is subject to big risks. Prematurity of a germ is shown that birds are forced to hatch out baby birds in eggs, creating it temperature of the body.
It would seem, an obvious defect of evolution here. However the bird exempted from egg becomes easy, capable to fast and maneuverable flight again. So difficult process of incubation of eggs and bringing up of cubs is a way to support ability of birds to flight.
Division of birds into 2 parts also is connected with maintenance of ability of birds to flight: ptentsovy and vyvodkovy. Ptentsovy are birds at whom cubs are brought naked, helpless, blind. There are they cannot therefore parents are forced to bring up them to full plumage and emergence of ability to flight. As a rule, the birds capable to fast, maneuverable and far flights belong to this category.
At vyvodkovy birds though they also hatch out the eggs, baby birds are from the very first days capable to move and be fed independently under protection of the parents. Usually birds who do not fly belong to this category or all natatorial fly badly and also.
Reproduction of pigeons
In different regions reproduction of pigeons happens at different times. However anyway they begin the cooings, dances and other courtings in the early spring when snow descends.
Pairing of pigeons can begin from 6 months. it would Seem, the earlier, the better – at young strong individuals and the posterity has to be strong and healthy. However it not absolutely so. At such age it is better not to make pairing of birds. The matter is that if too young birds also copulate, then can lay not oosperms. Early pairing badly affects also health of birds. They slow down growth, they live not for long, can be ill and lag behind in development from the peers.
The best period for receiving posterity is the age 1-2 years. During this period at birds the organism is already well created, the immunity developed. Then with age the fertility increases and remains for about five years.
It is the best of all to stimulate reproduction of pigeons aged from 1 year. It is possible to determine maturity of pigeons by a voskovitsa. It serves as the best indicator of a polovozrelost of birds. Parovka of pigeons stops when couple reaches age of 5 years. At this time pigeons give weak posterity again or lay fruitless eggs. The century of pigeons is short.
Reproduction of birds, especially ptentsovy which pigeons, business troublesome treat. It demands patience, knowledge and understanding that each look has features which should be considered.