5. CLASSIFICATION OF FARM ANIMALS BASED ON THE CLASS THE ANIMAL BELONGS TO:
The class the animal belongs to refers to the group that a particular animal belongs to in the animal kingdom.
Farm animals are therefore classified into two groups based on their classes. These two classes in the animal kingdom are: (a) Mammalia and (b) Aves
(a) Mammalia: All mammals belong to this group. Their bodies are covered with hairs. They have heterodont dentition, that is, they possess different sets of teeth. Reproduction is sexual and fertilisation is internal. They have strong bones that give support to the body. They have two pairs of limbs (forelimbs) and the hind limbs (legs) which enable them to move. They do not lay eggs and they have mammary glands that produce milk to feed the young ones.
(b) Aves: All birds belong to this group. They have beaks without teeth used for feeding. They possess feathers which aid them in warmth, protection and for flight. They have wings which may be used for flight. Their entire bodies are covered with feathers except the hind legs which are covered with scales. They have rigid and hollow bones with air sacs which make then light during flight. They lay eggs and do not have mammary glands
6. CLASSIFICATION OF FARM ANIMALS BASED ON THEIR MODE OF REPRODUCTION
The mode of reprodcution refers to the way in which the adult female animals give birth to the young ones.
Farm animals are therefore classified into two groups based on the mode of reproduction. These two groups are: (a) Oviparity and (b)
(a) Oviparity: This is defined as a process of reproduction in animals in which the animals lay eggs. The embryos grow and develop within the eggs after which the eggs are hatched to give rise to new offspring. The eggs may be fertilised inside or outside the body of the female animal. However, the development of the embryo inside the egg takes place externally i.e. outside the body of the female.
Animals which lay eggs or do not give birth to the young ones alive are called Oviparous animals. Examples include domestic fowls, ducks, geese, ostrich, pigeons, etc.
(b) Viviparity: This is defined as a process or mode of reproduction in animals in which such animals give birth to young ones alive. In other words, these animals do not lay eggs. The eggs or ova are fertilized internally inside the body of the female animals. The development of the embryo inside the egg or ovum takes place internally.
Animals which give birth to the young ones alive are called viviparous animals. Examples are found in mammals only such as cows, sheep, goats, rabbits, pigs, etc.For more class notes, videos, homework help etc download our Mobile App HERE
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