How do cattle mate? -Baidu Encyclopedia

(1) Natural mating (natural mating)

Refers to the direct mating of male and female animals. According to the degree of human intervention, it can be divided into the following four ways:

1. Free mating is found in the herd. Male and female animals are mixed grazing all year round. Once the female animal is in estrus, the male animal will mate with it at will, which is the most primitive mating method without artificial control.

Grouping mating

During the breeding season, females are divided into several groups, and one or several selected males are put into each group for natural mating. In this way, the reproductive times of male animals are properly controlled, and a certain degree of group selection and matching is realized. However, it is still impossible to prevent the spread of reproductive diseases, the mating utilization rate of male livestock is still limited, and the expected date of delivery of female livestock is difficult to predict.

Mating in a circle

Male and female animals are usually kept in isolation. When a female animal is in estrus, she is put into a pen to mate with a specific male animal. This method overcomes the shortcomings of free mating to a certain extent, and the mating utilization rate of male animals is improved, and the selection and pairing are also strict.

4. Artificial assisted mating

Male and female animals are kept strictly separately at ordinary times. Only when the female animal is in estrus, will it mate with a specific male animal according to the original matching scheme, and prepare the female animal for Baoding and detoxification, and at the same time take other necessary measures to help the male animal mate smoothly. Compared with the above three natural breeding methods, it increases the number of females that can be bred with stallions and prolongs the service life of stallions; It can control the time of calving, which is beneficial to the planning and management of production; Strict individual selection and matching can be carried out, and pedigree can be established, which is beneficial to variety improvement; According to the breeding records, the expected date of delivery of the female livestock can be calculated; And prevent the spread of diseases to some extent. It is a more scientific and artificially controlled natural mating method.

(2) mating time

The process of combining with a fertilized egg and implanting it into the uterus. Therefore, breeding must combine sperm and eggs at the best time to achieve the best pregnancy effect. In pig production, breeders must master the characteristics of each pig and breed oestrus sows in time. The best breeding time is influenced by the following two factors:

Fertilization ability of sow reproductive organs sperm: within 30 minutes after natural mating, some sperm can reach the fallopian tube. After several hours of mating, most of the sperm are in the uterine body and the uterine horn, and after 15.6 hours, most of the sperm can appear in the fallopian tube and the front of the uterine horn. The longest survival time of sperm in sow reproductive organs is 42 hours. In fact, sperm usually have 25-30 hours of stress after mating.

Energy absorption of eggs: the energy absorption time of an egg is very short, usually several hours, and the longest can reach 15.5 hours.

Appropriate mating time: the more accurate mating time is after mating, and ovulation is the best time for sperm to just reach the fallopian tube. But in production, this time is difficult to master. Breeding can be carried out according to the following rules:

The breeder presses the sow's back, and if the static reflex begins to appear, breed in time after 12 hours; If the sow has obvious oestrus symptoms and gently presses the sow's back, there will be standing reflex, so it has reached the peak of oestrus and must be bred immediately.

The mating times should be more than two times, and the mating should be repeated 8- 12 hours after the first mating to ensure a better pregnancy rate. According to the test report, sows are bred within 25 hours after starting to accept the boar climbing, and the conception rate is good, especially 10-25.5 hours, which can reach 100%. After breeding, the results are poor.

There are generally three ways of sow reproduction: single mating, compound mating and double mating.

Monogamy: Sows mate only once in estrus. Its advantage is that it can reduce the burden of boars, raise fewer boars and improve the utilization rate of boars. However, this method may reduce the pregnancy rate and litter size.

Compound: in the estrus of a sow, the same boar is used twice. That is to say, sows are mated once after the first mating and once every 8- 12 hours. Its disadvantage is that it increases the number of boars.

Reducing the utilization rate of boars can improve the conception rate and litter size of sows. According to some data, mating sows three times every 12 hours can increase the pregnancy rate by 3.4%, and the average number of live piglets per litter can be increased by 0.5 to 1.3.

Double mating: in large-scale pig farms, it is best to use double mating to improve the reproductive performance of sows. The method is to mate with two boars of the same breed or their semen (artificial insemination) when sows are fertilized. For the first time, when a boar is directly mated or artificially inseminated, another boar is directly mated or artificially inseminated after 12 hours.

The advantages are that it can make up for the loss caused by the first boar mating failure or poor semen quality, reduce the burden on boars, ensure sperm vitality, and thus improve the conception rate and litter size of sows.