1. Ejaculation quantity: The ejaculation quantity of boars varies with breed, age, sperm collection method, sperm collection technology level, sperm collection frequency and nutritional status, and varies greatly among individuals. 2. Semen color. Normal semen is generally grayish white or milky white. If the color is abnormal, it belongs to abnormal semen and cannot be used for insemination. 3.pH: Pig semen is weakly alkaline, and the pH value of normal semen is between 7.0 and 7.5. Take a little semen on the acid-base test paper with a glass rod. Compared with standard colorimetric paper, anything beyond the normal range can not be used for insemination.

4. Smell: Normal semen has a special fishy smell. If there is foul smell or other rancid smell, it belongs to abnormal semen and cannot be used for insemination. Stinky semen is a sign of inflammation, and semen contaminated by foreskin has a strong odor. Semen that smells like urine and ammonia should not be used.

5, sperm motility check. The vitality of fresh semen is generally 0.7 ~ 0.8, and semen with vitality lower than 0.6 should be discarded.

6. Sperm density refers to the number of sperm contained in each milliliter of semen, which is counted by blood cell counting plate or determined by semen densitometer. See the instructions for use of semen densitometer.

7, deformity rate inspection. Abnormal sperm include giant, short, broken tail, decapitated, acrosome shedding, protoplasm drop, big head, double head, double tail, broken tail and other sperm. They generally can't move in a straight line and have poor fertilization ability. The abnormal rate of pig sperm is above 20%, so it is not suitable for use.