In cattle breeding, reproduction is an important factor affecting the profitability of live cattle and milk production. Therefore, a very important aspect is the constant observation of animals and detection in time of heat in the herd.
What is estrus and the oestrus cycle?
Heat is the main phase of the oestrus cycle, in which there is an increased activity of the female reproductive system. Cows typically reach sexual maturity at 7-9 months of age and begin their oestrus cycle upon reaching puberty. This period is 17-25 days and is counted from the day of the onset of heat symptoms to the beginning of the next heat. Cows are polycyclic, which means that their oestrus cycle lasts all year round, compared to other livestock (sheep, goats, horses) that only have it a few times a year.
Symptoms of estrus
Recognizing the symptoms of oestrus is the key to successful breeding of cows. What should you pay attention to?
Behavioral changes: anxiety, growling, jumping up, licking neighboring cows, looking for physical contact, flexing the back, loss of performance and appetite;
Changes in external appearance: congestion of the external genitalia, swelling of the vulva, discharge of mucus from the reproductive organs.
Often a cow does not show symptoms or the symptoms are so faint that it is difficult to spot heat.
Reasons for silent heat:
- Insufficient environmental conditions;
- Incorrect nutrition;
- Mineral and vitamin deficiencies;
- Lack of movement;
- No expression of natural behavior.
Frequent problems with reproduction and the effectiveness of insemination cause growing interest among breeders in new methods of heat detection. Belong to them:
- Visual observations – at least 3 times a day;
- Progesterone tests in milk or plasma;
- Electrical resistance of vaginal mucus – reduction by 20-30 units;
- PH measurement of vaginal mucus;
- Measurement of body and milk temperature
- The use of devices monitoring changes in activity (pedometers, actinometers).
- The more methods are used, the greater the probability of heat detection.
Optimum mating date
Heat lasts only 12-28 hours, so it is important to monitor the cows and detect the first symptoms early for a successful insemination. In malnourished cows, in poor condition, heat may be shorter and its symptoms imperceptible.
Cattle breeding is the basis for profitability of breeding and milk and live cattle production. The multitude of available devices and methods of heat detection will allow you to choose solutions that will work in a specific herd.