Today, world-class reproduction targets are 30 pigs born per sow per year, a litter average of 14 pigs and a 96 percent survival rate. That means your operation has to be managed to near perfection to achieve those targets. Within that effort, successful artificial insemination strategies can be among the more crucial points to tackle.
To help you achieve world-class status, Phil Burke, a technical services manager for the sireline business at
Genetics. Start with valuable genetics. Find out what you need and what your packer needs, he says. Then identify the best package to deliver that product consistently.
Also consider whether you should buy boar semen or adopt on-farm collection. Buying semen means you can have it delivered on the day you want it, at the time you want it and in the amount you want. Purchased semen comes from boars that have a high genetic turnover. Boars on your farm probably are kept longer, which means you are losing out on the latest genetics.
Guilt development. The goal here is to have gilts entering your herd at the right age, body weight and body condition, as well as the right genetic package. To get the right gilts, however, you have to follow the rules. For instance, you must realize that gilt development begins early in life and that you cannot raise or feed a gilt as a commercial animal. The goal is to maximize longevity, not throughput, which is the goal in the finisher.
“Using commercial feed rations means the gilt will grow so quickly and so large that she’ll face unnecessary stress on joints, feet and skeletal mass before those things are fully developed,” he explains.
Proper gilt development includes setting targets for the first breeding. He points out that breeding at third estrus is better than breeding at second estrus. Preferably, it occurs when the gilt is at 225 to 230 days of age and at least 280 pounds. The gilt also should have 16 mm to 18 mm of backfat, with a minimum of 14 mm.
Boar exposure during the finishing phase (at 150 days old and older) will naturally inhibit growth and weight gain by stimulating hormones that trigger reproductive development.
Herd and parity management. When culling females, monitor the parity mix and make sure that quality gilts are always coming into the system.
Also, maintain a strong culling policy. “I work with some farms that have a three-strikes-per-lifetime rule,” notes Burke. This is severe, but if a sow or gilt returns three times in her lifetime, she is eliminated.
Of course, in order to enforce such a policy, you first have to ensure that you have enough gilts coming back into the herd.
Boar semen source. Producers who don’t buy boar semen believe it is less expensive to process it on the farm. While that is correct, “it’s not nearly as cheap as people think,” says Burke. He contends that there is less than a dollar difference between buying semen and on-farm collection. “On-farm collection costs include your time; the person who fills in when you’re not there; efforts to ensure semen is always available; regular boar replacements; and efforts to maintain semen quality.” On-farm costs are $3.50 to $4 per dose, without including the boar’s purchase price.
Sometimes it is best to collect semen on the farm, but always think about what an off-farm source could provide. Burke says those things include time spent on semen collection, extension, morphology and fertility; as well as checking semen samples on day two, three, four or five. If you buy semen, ask about its concentration, the quality-control measures, extenders used and shelf life. Also, does the supplier periodically send semen samples elsewhere for third-party validation?
Semen management. This is one of the simpler things to do on the farm, but it’s a common weakness. The challenge is making sure that you have the right amount of semen on the right day. “In most cases, with purchased semen you can adjust your order as needs change, even on the morning of delivery,” notes Burke.
Many producers don’t rotate semen doses, but Burke is an advocate of the practice. “Because every time you physically rotate semen you have an opportunity to check the storage temperature to make sure that everything is ok and that the doses aren’t leaking,” he notes. “Every time you rotate semen, you expose the sperm cells to nutrients that extend shelf life.” When you rotate semen, do it slowly. Do not shake it. Temperature fluctuations negatively affect semen shelf life and fertility. Whenever you move boar semen from the cooler to the barn, try to maintain a temperature as close to that of the cooler, even while inside the barn.
This can be especially difficult on a hot, summer day, so take only as much semen as is needed for an hour of inseminations. Go back and get more when you need it.
Heat detection. Everyone knows that sows and gilts should only be bred when they’re in heat. Still, Burke is amazed at how many farms he visits where people are inseminating animals that are just coming into heat.
“Producers and employees don’t always wait for animals to be in full standing heat,” says Burke. “If you know for sure that a sow or gilt would stand for a boar, then you should go ahead a breed her. Otherwise she’s not ready.”
Check for heat twice a day, and don’t use the vulva as the only indication of her heat status. Check out her ears, head and eyes, says Burke. “A sow in heat has glazed eyes. She should be oblivious to your presence.”
Timing. Burke recommends dividing animals into six distinct groups: 1) gilts, 2) early cycling sows, 3) normal-cycling sows, 4) late-cycling sows, 5) recycles and 6) hardheads. “They all need to be treated as individuals and managed accordingly,” he says.
Optimal insemination timing is based on twice-a-day heat checks. For sows that have just been weaned, insemination timing varies from five to six days for sows in the early cycling group; six to seven days for normal-cycling sows; and almost seven days for late-cycling sows, gilts and re-breeds or recycles. (See accompanying chart.)
Insemination practices. Heat checks should be done separately from semen insemination in order to prevent pre-exposing other animals. On large farms, Burke believes inseminations should be done as a group effort. He advocates having two or three people work together. It provides support and helps reduce boredom.
See that technicians use only sealed semen catheters, as well as single-use, dry paper towels to clean vulvas before inseminating sows.
Maintain continuous boar exposure during and after the A.I. process. “I recommend using the smelliest, nastiest-looking boar you can find,” says Burke. Have technicians see that continuous underline stimulation occurs. This will encourage the sow to release oxcytocin, which helps semen move to the right place at the right time.
Aim for six to eight inseminations an hour per technician. After one hour, the technician should take a break, then go get more semen before returning to the barn. It’s important that the technician is relaxed and focused.
Records. Keep precise records, including graphics, that relate directly to gilts and sows so that different personnel can easily review an animal’s history. Consider color coding the data to help differentiate important areas. Train personnel to understand records as well as the implications of various data.
Pregnancy detection and gestation management. The best pregnancy check in the world is a large, mature boar, says Burke. “The new machines are excellent, but you can’t beat a big, ugly boar. Give him time to walk the barn and he will find a female in heat earlier and more consistently than any machine on the market.”
Walk the boar slowly, giving sows and gilts a chance to respond. A technician should walk four feet or so behind the boar, all the while looking around the barn, to see if surrounding females also are responding.
“If in doubt, get her out,” is Burke’s favorite motto. “If a sow is in heat and you put her into a pen with a boar, she’ll go into a standing reflex, no matter what type of sow she is.”
Finally, if you need to move a sow or gilt, do so within the first 48 hours after the final A.I. session. If you can’t move her then, wait for 30 days, says Burke. The most critical time not to move her is 10 to 14 days after breeding. Always move a sow or gilt patiently, slowly and by itself. Don’t crowd the animal through doorways, and never move it during the afternoon heat.
Follow these steps and your artificial insemination program will be on its way to world-class status. n
By Roger Stevens, a freelance writer in