Reproduction is the amazing process through which farm animals give birth to young ones. It all begins when the animals reach sexual maturity, which varies depending on the species.
For instance, cattle become sexually mature around 15 months, while goats and sheep take about 6 months. Poultry, on the other hand, mature at approximately 18 weeks.
The Oestrus Cycle
The oestrus cycle marks the reproductive cycle in female farm animals when they are not pregnant. It’s influenced by a hormone called oestrogen and varies among species:
1. Cows: Every 20-21 days
2. Ewes: Every 17-21 days
3. Sows: Every 14-28 days
4. Does (goats): Every 17-21 days
5. Does (rabbits): Spontaneous
Ovulation
Ovulation is the release of eggs from the ovaries into the fallopian tubes, controlled by hormones like luteinizing hormone (LH) and follicle-stimulating hormone (FSH). The timing varies among farm animals:
1. Cows: 10-14 hours
2. Ewes: 20-24 hours
3. Sows: 24-36 hours
4. Does (goats): 12-36 hours
5. Does (rabbits): Spontaneous
Heat Period
The heat period is when female animals are receptive to mating. Signs include restlessness, mucus secretion, and a swollen vulva. This period varies:
1. Cows: 5-24 hours
2. Ewes: 35-36 hours
3. Sows: 40-48 hours
4. Does (goats): 40-50 hours
5. Does (rabbits): Spontaneous
Signs of Heat in Farm Animals
1. Restlessness
2. Mucus secretion
3. Swollen vulva
4. Loss of appetite
5. Viscous vaginal secretion
6. Abnormal body temperature
7. Grunting
8. Frequent urination
9. Standing still to be mounted
In summary, ovulation (egg release), heat period (mating readiness), and oestrus (preparation for the next ovulation) or pregnancy follow successful mating.
Mating
Mating, or sexual intercourse, involves the male’s penis entering the female’s vagina, leading to sperm introduction. It can occur naturally or artificially.
Natural Mating
Examples include:
1. Flock Mating: Males and females freely mate.
2. Pen Mating: Used in pigs and poultry, where a male is paired with several females.
3. Stud Mating: Involves a male with proven qualities mating selectively.
Artificial Mating
Also known as artificial insemination, where sperm is collected and inserted into the female’s vagina. It offers advantages like prolonged semen use but requires expertise for success.
Fertilization and Gestation
Fertilization occurs when sperm and egg fuse, followed by implantation in the uterus. Gestation, under progesterone’s influence, varies:
1. Cattle: 283 days
2. Goats and Sheep: 150 days
3. Pigs: 114 days
4. Rabbits: 31 days
5. Chickens: 21 days
Parturition
This is when animals give birth, such as calving for cows or lambing for ewes. Signs include mammary gland enlargement and restlessness.
Lactation
Lactation is the production of milk triggered by oxytocin, essential for nurturing newborns. Colostrum, produced in the first days after birth, is vital for its high protein and vitamin content.
Egg Formation in Poultry
Eggs form in the ovary and move through the oviduct, where they undergo various stages before being laid.
Male and Female Reproductive Hormones
Hormones like testosterone (male) and oestrogen (female) influence reproductive functions, including secondary sexual characteristics and sperm/egg production.
Understanding these reproductive processes is crucial for farmers to manage breeding effectively and ensure healthy offspring in their livestock..