Question: What are the benefits of artificial insemination (AI) and how is it done?
Joël Kotzé from Taurus, an AI company, sums up the benefits:
“Dairies don’t use bulls. Imagine a bull among 200 cows… In beef cattle farming AI is normally only used for the top 20% of the cows, because beef farming tends to be expensive. For developing or subsistence farmers, however, AI is the answer, because it’s cheaper than buying a quality bull.
“A bull that services 25 to 30 cows per season will cost between R20 000 and R30 000. Semen, on the other hand, costs about R50 a dose, which means you can artificially inseminate 400 cows for the price of one R20 000 bull! That makes more economic sense.”
Here’s a step-by-step procedure:
HOW TO HANDLE SEMEN SAFELY
- Ensure the semen straws are always covered with liquid nitrogen. (If they are not covered, the semen will thaw and be useless).
- Do not expose the semen straws to direct sunlight, dust, water, soap or powder.
- Identify the bull before removing any straws. Most farmers store the semen of more than one bull in a flask. You can identify the semen of individual bulls correctly with the help of a disc, supplied by most registered AI companies.Place it inside the flask lid so you can see where each bull’s semen is stored. It is a good idea to keep records detailing which bull has been used to inseminate which cow. You’d be very disappointed if you inseminated semen from the wrong bull!
- Make sure the storage tank is upright during transport.
- Check the outside for signs of frost and spills of liquid nitrogen.
- Close the storage tank with its own lid.
- If nitrogen gas accidentally burns you, pour cold water on the sore and apply a cold compress. Go to a doctor if it gets into your eyes or if the skin forms blisters.
IS THE COW ON HEAT?
- A cow goes on heat every 21 days, which is the normal cycle.
- When a cow is on heat, you will notice mounting of cows by cows, clear or turbid bull string, swollen or red vulva,
- bellowing or restlessness and tail hairs tousled because of mounting.
- If you notice a cow is on heat in the morning, you have to perform AI on the afternoon of the same day.
- If you detect she is on heat in the afternoon, you have to perform AI the next morning.
PREPARING FOR ARTIFICIAL INSEMINATION
Buy good, fertile semen, preferably from a registered AI company, and ask for the certificate that shows the semen has been tested. Semen sometimes carries deadly diseases that can wipe out your entire herd.
- Make sure the cow is on heat and in good health.
- Inseminate no less than 60 days after calving.
- Use a crush pen.
- Make sure that the instruments are in good working order.
Use the following:
- Sharp scissors
- Paper towels or cotton wool
- Full arm-length gloves
- Sanitary sheaths
- Wide-mouthed thermos flask of water (35°C to 37°C)
- Nitrogen flask
FINDING THE CERVIX
- Apply lubricant to the back of your gloved hand and the opening of the rectum.
- Put 1 finger into the rectum, gently stretching the finger forward.
- Now put in the other fingers, holding them together.
- Gently push your arm wrist-deep into the rectum.
- Apply downward pressure on the reproductive organs and move your hand from side to side along the pelvic rim, where the abdominal cavity starts.
- Press the fingers down to feel where the cervix is.
- It is important not to use disinfecting soaps that irritate a cow’s rectum and are very harmful to sperm.
- Most soap sold to dairies contains strong disinfectants.
- Use a soap recommended by the AI company.
THE INSEMINATION PROCEDURE
- When your instruments are ready, place the thermometer in the thermos, close to the nitrogen flask.
- Warm the pistolet between your hands.
- Thaw the semen straw in warm water for 20 seconds.
- Remove the straw and dry it with a paper towel.
- Insert the straw into the pistolet.
- Stand behind the cow, clean the vulva and remove any faeces (in that order).
- Apply downward pressure to the open vulva lips.
- Insert the pistolet into the vagina without touching the vulva.
- Find the cervix as described above.
- Inseminate and remove the pistolet.
- Bulls in good condition should produce thick, creamy semen.
Also read: Get the best from your new bull
The conception rate is the percentage of cows that become pregnant through AI, or by natural mating.
Factors that affect conception rate are:
- Nutrition – cows in good condition and with good body mass come on heat and get pregnant quicker.
- Semen and semen straws – handle with great care.
- Insemination techniques – be careful not to damage the fragile lining of the uterus. Good hygiene prevents infection of the uterus.
Always insert the semen into the uterus in the correct way. Make sure that the cow is on heat.
- This article was written by Malixole Gwatyu and first appeared in Farming SA.