What is puberty?
Puberty is a period at which sexually organs are functionally developed and animals become able to release the gametes.
Puberty is defined as the achievement of the ability to reproduce. In domestic animals, it is characterized by the expression of estrus in females and by the presence of sperm (at least 50 millions of which >10% are motile) in the ejaculates in males.
Note: Amongst females of the domestic species, puberty precedes the development of physical
maturity and although they become capable of reproducing, their efficiency, particularly with respect to their fecundity, has not reached its maximum. When the female animal reaches puberty, the genital organs increase in size. During the prepubertal period, the growth of the genital organs is very similar to that of other organ systems, but at puberty their growth rate is accelerated.
Females of domestic species reach the age of puberty at the following times:
Bitch: 6 – 20 months
Cow: 7 – 18 months
Dow: 4 – 8 months
Ewe: 6 – 15 months
Mare: 1 – 2 years
Queen: 7 – 12 months
Sow: 6 – 8 months
The changes that occur at puberty depend directly upon the activity of the ovaries.
Generally age at first oestrus is not accompanied by ovulation in females thus it is not a
true measurement of puberty. The age at first ovulation is difficult to be determined.
Sexual maturity
Stage of well growth and development of reproductive system,reached after puberty,capable tp produce offspring.
Sexual maturity in female
Reproductive tracts enough to fertilize and conceive a fertile zygote and produce a viable offspring.
Sexual maturity in male
Production of standard sperm concentration per ejaculate (8-16 billions),number of spermatozoa 500 millions/ml,motility rate 70-80%,standard testicular size 34-36 cm.
Factor's affecting the onset of puberty
There have two main factors responsible for onset of puberty
Genetic factors
1.Breed: Smaller,European, Dairy=Early puberty
2.Species: Smaller =Early puberty
3.Testicular size: Large in size=Early puberty
4.Types of breeding: Crossbreed=Early puberty
Environmental factors
1.Nutrition and body weight: Malnutrition causes delayed puberty,if animal gains about 70-80% body weight easily reach in puberty.
2.Season: Green grass causes early puberty
3.Growth: Slower growth causes delayed puberty.
4.Climate: In temperate zone -early puberty, Tropical zone-delayed puberty.
5.Disease condition causes loss of body weight as a result puberty is delayed.
6.Social cause- presence of bull enhance estrus cycle.
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