| Animal husbandry: Animal diseases; How animals reproduce |
We have studied how plants reproduce themselves (see Booklet No. 3, page 14).
We shall now study how animals reproduce.
It is very important to study this, in order to improve animal husbandry.
When you have a good knowledge of how animals give birth to their young, of how they reproduce, you can make a better choice of the animals for breeding.
To get a good harvest, a farmer chooses good seed (see Booklet No. 3, page 24).
To get good animals, a farmer chooses good breeding stock.
To get a good harvest, a farmer chooses good varieties of seed (see Booklet No. 3, page 22).
To get good animals, a farmer chooses good breeds.
To understand how animals reproduce, we must study the reproductive organs of the females and males.
The reproductive organs of the female are all inside the animal.
You can see only the entry to the system which is called the vulva.
Flowers have ovaries which contain ovules (see Booklet No. 3, page 11).
When the ovules are fertilized by pollen, the ovules become seeds.
Female animals have two ovaries which normally produce one or more ova. (In animals the female reproductive cell is called ovum, plural ova.)
If the female is covered (served) by the male at this time, the ovum is fertilized. It develops and becomes a young one in its mother's womb.
This system consists of two testicles, which hang between the hind legs, the penis, and two ducts which connect the testicles with the penis.
Stamens give the pollen that fertilizes the ovule in a flower (see Booklet No. 3, page 14).
Testicles give the semen that fertilizes the ovum.
The fertilized ovum becomes a young one in its mother's womb.
When the female carries a young one in her womb, we say she is pregnant. Pregnancy begins with fertilization and ends with the birth of the young animal. It lasts a shorter or longer time depending on the kind of animal.
If the mother already has a young one, she must not feed it during the last stage of pregnancy, because the baby the female is carrying needs more food (see Booklet No. 8, page 21 ). The female cannot feed both the young animal already born and the one that is growing in her womb.
Some days before the birth, the udder of the mother swells.
At the time of birth, some of the membranes which cover the baby in the womb come out. These membranes contain water. Next, you see the legs come out, either the two forelegs or the two hind legs.
Sometimes you have to pull downward a little on the legs of the young animal so as to help the birth.
When the young animal has come out, if it is still joined to the mother by the umbilical cord: cut this and clean it carefully.
After the birth, the rest of the membranes come out. They must all come out. Otherwise they may rot inside the mother and cause her to die.
When the young animal is born the mother licks it with her tongue.
Let her do this.
At this time the mother is often thirsty. Give her water to drink.
During the first few days after the birth, the mother's milk is thick and yellow.
The young animal must drink this milk, which will clean its digestive tract.
Take great care of new- born animals. They are delicate. They easily catch parasites and diseases.
To protect them, have them vaccinated (see page 10).
Take good care of the young animals. feed them well and house them well. Otherwise they may die and you may lose a lot of money.
Animals that are to produce offspring must be well chosen.
Breeding animals must be well chosen because the offspring are like the parents.
Cows that give a lot of milk usually produce females that will also give a lot of milk.
This quality is passed on from the mother (dam) to the daughter. (In animal breeding the mother is called the dam).
Pigs that grow and gain weight quickly usually produce males and females that grow and gain weight quickly.
This good quality is passed on from the dam to her young ones.
Sheep that have well- developed bones and muscles usually produce offspring that have well- developed bones and muscles.
This good quality is passed on from the dam to her young ones.
Pigs that grow and gain weight quickly, that have well- developed bones and muscles, usually produce offspring that grow and gain weight quickly, that have well- developed bones and muscles.
The young ones often have the good qualities of their father (sire). (In animal breeding the father is called the sire.)
Bulls born from a cow that gave a lot of milk often sire females that will also give a lot of milk.
The good qualities of the bull's dam are often passed on to the bull's daughter.
Cattle that have little resistance to sleeping sickness produce calves that have little resistance to this disease.
The parents' bed quality is passed on to their young.
A badly formed pig with poorly developed bones and muscles often produces badly formed offspring.
The parents' bad qualities are passed on to their young.
The good qualities of the male and the female are often passed on to their young.
The bad qualities of the male and the female are also passed on to their young.
So it is very important to make a good choice of males and females.
It is easier to improve a herd by a good choice of male.
A female passes on her good qualities to a few offspring each year.
A male passes on his good qualities to all the offspring of the herd.
• A male should not produce young from one of his daughters.
The offspring would not be of good quality.
If you want to have animals that are strong for work; that give a lot of milk; that gain weight quickly and make plenty of meat, you must choose breeding animals that are:
• well formed.
You must eat or sell all poorly developed animals. Keep animals that have plenty of muscle. The muscles of the back and rump are the most important, because they give the best meat.
• resistant to disease.
For example, do not raise zebu cattle in forest country where there is tsetse fly.
• good producers.
It is important to choose animals that produce a lot. For example: pigs that gain weight quickly; cows that give a lot of milk; chickens that lay plenty of eggs; ewes that produce two lambs.
• not too young or too old.
A breeding animal that is too young, not yet fully grown, gets tired, does not gain weight. It becomes a bad breeder. Its offspring will be poorly nourished, for a female cannot both feed the young she is carrying, and go on growing herself.