What is Ovulation in Camels?
Ovulation is a natural process in the reproductive system of camels, where the mature follicle (egg) bursts, and the egg is released from the ovary into the uterus. Here, fertilization occurs by the sperm from the camel, leading to embryo formation. Unlike other animals, ovulation in camels occurs only during mating (copulation) and not automatically as it does in other species.
Understanding the Ovulation or Estrous Cycle in Camels
The ovulation cycle in camels is divided into three main stages based on the size of the follicle (egg) present on the ovary:
- Egg Growth Stage
- Egg Maturation Stage
- Ovulation or Egg Degeneration Stage
Stage 1: Egg Growth Stage
Where Are the Eggs Located in Camels?
The eggs are located on the surface of the ovaries, which are connected to the uterus. Each female camel has two ovaries, and the ovary is the most crucial organ in the reproductive system of camels.
Egg Development Process
The ovulation cycle begins with the growth of numerous eggs simultaneously, ranging in size from 0.1 to 1 cm. This growth phase lasts between 6 to 10 days. The eggs gradually increase in size at a rate of 1 mm (0.1 cm) per day until they reach 1 cm in size. At this point, all the eggs except one begin to degenerate. The remaining egg continues to grow and enters the second stage: egg maturation.
It’s important to note that these immature follicles do not respond to hormones, so ovulation will not occur if the camel is mated during this stage (or if an ovulation injection is administered).
During this phase, the female camel shows no external signs of readiness for mating, whether she is receptive or not. Some camels may allow mating during this stage, but pregnancy will not occur due to the immaturity of the egg. In such cases, mating may have occurred earlier than the optimal time.
Stage 2: Egg Maturation Stage
This stage, also known as the Receptive Stage, begins when a mature egg is present, with a diameter ranging from 1 to 1.4 cm. At this point, the egg is ready for ovulation if mating occurs or if the ovulation injection is given.
Timing and Optimal Mating Period
The end of this stage depends on whether mating occurs. If mating does not occur, the follicle continues to grow until it reaches 2 cm. At this size, the follicle either begins to degenerate or continues to grow.
The Golden Window for Mating
The optimal egg size for mating is between 1 cm and 1.5 cm. The chances of successful ovulation decrease if the egg is larger or smaller than this range. This golden window for mating lasts for 4 to 5 days, during which time successful mating (fertilization) can occur.
Veterinarians can measure the egg size using ultrasound to determine the optimal timing for mating and can control the timing with specific medications and hormones.
If Mating Occurs (or Ovulation Hormone is Administered)
The egg bursts (ovulation), and the egg is released into the uterus, awaiting sperm for fertilization and embryo formation. During this stage, the female camel will be fully receptive to the male camel and will display all signs of receptivity.
Stage 3: Post-Ovulation Stage (In Case of Mating)
After ovulation, the burst egg transforms into what is known as the Corpus Luteum. The corpus luteum secretes the hormone Progesterone (the pregnancy hormone), which prepares the uterus for the developing embryo (the egg after fertilization).
Progesterone is the hormone responsible for the female camel becoming non-receptive. Any female camel that is mated with a mature egg will develop a corpus luteum and secrete progesterone, leading to signs of non-receptivity 3 to 5 days after mating. This hormone is also measured in blood tests to determine if the female camel is pregnant.
If Pregnancy Occurs
The corpus luteum enlarges and continues to secrete the pregnancy hormone (progesterone) until birth. No pregnancy in camels can continue without sufficient levels of progesterone.
If Pregnancy Does Not Occur
The corpus luteum begins to degenerate and die, and the progesterone level decreases until it almost reaches zero. Simultaneously, some eggs begin to grow again, starting a new cycle.
Conclusion
Understanding the ovulation cycle in camels is crucial for breeders and veterinarians. In upcoming articles, we will discuss the most common ovulation problems in camels and how to treat them.