When they get the injections from a rooster's comb, the rooster does have to be killed. They can get rid of a rooster's comb without killing it but it has to be on the first day that it is born.
It's called a rose comb usually a rooster breed from Spain.
A hen is officially an adult when she starts laying and has a full comb and wattle. A rooster is officially an adult when he starts crowing, fertilizing eggs, and has a full comb and wattle. Remember that a hen's comb and wattle should be smaller than a rooster's comb and wattle.
The comb of a young rooster (cockerel) should start to show by the end of the first month and will grow much faster than the comb of a pullet. Keep in mind not all chickens have combs, it depends on the breed of chicken you have.
If they have a comb
The thing on a rooster's head is called a comb.
A rooster
it is on top of their heads
It is called a comb.
The prepositional phrase in the sentence is "with the zigzag comb," which provides additional information about the White Leghorn rooster.
A rooster's comb is mainly used for regulation of body heat.
"With the zigzag comb"