A cock can fertilize 6 to 10 hens in flocks. With the cock, the hens produce fertile eggs that can hatch after 21 days hatching process. It will be difficult to produce fertile eggs if we have more hens than the roosters. Let says, I a flocks there are 40 hens with one roosters only. I think the rosters will not able to fertile the hens even you give it Viagra.
To overcome it, you can do artificial insemination in poultry. It is not easy. You have to message the chicken back to release the sperm. It needs time to learn it. It is better to collect the sperm at early morning. Do not let the sun shine the sperm that could damage the quality of it.
Mix the sperm Nacl normal saline at ratio 1:10. The sperm is only 5 ml so you can use 50 ml NaCl. In my country, some breeder use chicken yolk sac or green coconut water.
Inject the sperm to the hens. You can use the sperm mix for 30 hens.
With artificial insemination, the hens will not be suffered with the male pressure; while, the roosters does not need to fertile so many hens.
We can cross any chicken that we like to produce high quality breed or improve the breed quality.
In my country, the breeder uses this method to produce bekisar chicken. Bekisar is a descendant of green jungle rooster (Gallus Varrius) and landrace hens (Gallus domesticus. The Rooster is a wild chicken that is difficult to tame. It is also difficult to match it with landrace hens. The Rooster is nervous and does not dare with bigger hens. Some hens often bully the roosters too.
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