A sow's first responsibility is to have a lot of pigs, but that could all be for naught, if she's a poor milker. A sow's milk production plays a vital role in weaning weights and other maternal traits.
"Other than producing a lot of pigs, the sow's major responsibility is to produce heavy pigs at weaning, which makes milk production important," says Duane Reese, University of Nebraska Extension swine specialist.
Todd See, North Carolina State University swine specialist, agrees but points out that the impact of milk production may be decreasing. "With the trend of weaning pigs early, milk production is becoming less important," says See. Many sows hit their lactation peak at 21 days after farrowing, which is a week after SEW pigs are weaned."
Still, milking ability and weaning weights remain important economic considerations for your sow herd.
"Milking ability is economically important, especially as more weaned-pig producers are paid premiums based on weights," says Ken Stalder, University of Tennessee Extension swine specialist.
It's tough to determine the exact economic costs or benefits from good milking sows. Poor milk production could lead to a higher pre-weaning mortality rate, which can become costly, if not remedied.
"The cost to you is the vitality of your pigs," says See. "If you want them to be heavy enough at weaning to earn a premium or get a strong start in the grow/finish stage, the sow's milk production is critical."
Building a herd of productive-milking sows is achieved by selecting for weaning weights, which is a significant part of the maternal-line index, says Stalder.
Weaning weight, is a lowly heritable trait – about 15 percent heritability for 21-day weaning weight – which means improvement through selection could take some time. The use of heterosis is beneficial in improving weaning weights, says Stalder. "In general, crossbred pigs have more ability to withstand adverse conditions," he says.
Of course, anytime you select for one trait you risk giving up ground in another area. To improve weaning weights you might have to sacrifice some carcass traits, he notes.
Once you've selected your genetics, there are still plenty of management options you can use to keep your sows milking well.
A la David Lettermen, Reese came up with a Top 10 list of tips to get the most milk production out of your sows. Here are his tips:
1. Have excellent maternal genetics. "Selecting for maternal traits is the most important thing," says Reese. "You can't manage around that."
2. See that you have highly trained, dedicated people managing and caring for the animals. You must have workers who come to work and do their best every day, says Reese.
3. Avoid over feeding energy to gilts in gestation. Females that are overfed energy during their first gestation have impaired mammary gland development.
4. Avoid over feeding females during the last two weeks of pregnancy. Reese suggests feeding about 4 to 4.5 pounds per sow per day, starting two to three days before farrowing.
5. Avoid under feeding energy or amino acids during lactation. "Often sows are not allowed to maximize the amount of feed they want to consume," says Reese. "Some producers don't feed lactating sows aggressively enough."
6. Be sure you have plenty of clean, fresh, water. Milk is about 80 percent water, it's an important element. The flow rate from nipple waterers should be about four cups per minute, says Reese. You should check every sow station before putting a sow in and watch her closely while she's there.
7. "All-in/all-out management is critical," he says. "It allows you to reduce the number of pathogens in the environment that can cause mastitis."
8. Maintain optimum temperature in the farrowing house. Reese says the ideal temperature range is 65°F to 70°F, assuming you have zone heat for the baby pigs. Evidence shows that a hot sow reduces milk production.
9. Record the amount of feed added to a sow's feeder daily, so you can detect feed consumption problems. You need to know quickly when a sow reduces her feed intake.
10. "The pigs need to consume the milk the sow is producing," says Reese. "If the pigs are sick, or the litter is small, the sow will get the signal to stop producing as much milk."
The sow's appetite and feed intake are keys to good milk production. "You need high feed quality," says See. "Make sure the feed is not moldy. Also, feed smaller portions, but feed more frequently."
The sow's environment also influences feed intake. "You have to manage the cooling and ventilation systems to keep the sow cool in hot weather," says Stalder. "Make sure fans are operating optimally and that cool cells work at their maximum potential. You need to keep up with everyday ventilation and cooling maintenance, so when you need maximum output your facilities have the ability to do so."
If your sows' feed intake drops you may need to adjust your rations. "If the decline is more than 10 percent, you need to feed a diet that is more nutrient dense, with higher concentrations of calories and lysine to ensure the sows get the nutrients they need," says Stalder.
For example, if the sows' normal feed intake is 14 pounds a day and that falls to 12 pounds (about a 15 percent decrease) you need to increase the nutrient density in their rations by 15 percent. That way they will get the same amount of nutrients even though they're eating less feed.
"Milk production is better overall today because the industry has done a better job of managing the key impacts," says Reese.
Making sure your sows are producing enough milk can lead to heavier, heartier pigs at weaning, which can promote strong growth into the finishing stage. So, it pays to do what you can to make sure your sows "got milk."
Signs of Poor Milk Production
Milk production problems can be devastating to your weaning weights and the number of pigs weaned. But how can you tell if you have a problem before it's too late? Trusting your eyes is one way.
"You should be able to get an idea if your sows are producing enough milk by watching the piglets," says Todd See, North Carolina State University swine specialist. "The pigs should be active and healthy, or you should probably put them on another sow."
Watching baby pigs' behavior while nursing also can clue you in to problems with milk production.
"If pigs are getting a good dose of milk they should nurse for 2 to 4 minutes every hour or so," says Duane Reese, University of Nebraska swine specialist. "If you see the pigs at the udder more often than that, it may mean they're not getting enough milk."
Of course, pigs with other visible traits like poor body condition, hairy coats, a gaunt appearance and scours are also indicators for poor milk production.
If you don't trust your eyes, review past weaning weights for the sow. Strong milkers will generally continue to stay strong throughout parities, says See.
Mastitis and What to Do about It
Mastitis is the most common disease or udder irregularity to limit a sow's milk production.
When a sow has mastitis, the affected mammary glands usually are enlarged, more firm, warmer, more sensitive and often discolored when compared to other mammary glands, according to the Pork Industry Handbook. Research by Charles Martin and Ronnie Elmore, University of Missouri; William Wagner, University of Illinois; and Richard Ross, Iowa State University; shows that palpation of the mammary glands of each sow several times during the early post-farrowing period may reveal developing mastitis and allow for early treatment.
"Affected sows will have red, hot, inflamed udders," says Ken Stalder, University of Tennessee swine specialist. "One of the signs that something is wrong is if the sow lays on her belly, so the pigs can't nurse. That tells you nursing is uncomfortable."
Treatment for mastitis should be directed toward creating milk flow, while preventing secondary complications in both the sow and the pigs. The researchers recommend injections of oxytocin. Multiple injections may be necessary to produce milk.
In a perfect world, you'll never need the treatment, because you will be able to prevent mastitis. Prevention centers on herd-health management and nutrition. Immunization can be done in advance of anticipated problems, such as bacterial mastitis. Culture's from an infected sow's milk can be used to prepare a bacterin – however, your veterinarian needs to be involved with this process.
Reducing stress during gestation also is an important preventative measure. Sow acclimatization to the farrowing facility is one such stress-reducer.
Gestation feeding influences the potential for mastitis, as well. The under-fed sow cannot maintain blood-glucose levels as well as the well-fed sow, so resistance may be lower.
Additives to reduce mammary gland edema may be necessary if the herd has problems. A mixture of 12 parts potassium nitrate NF, four parts methenamine USP and one part dicalcium phosphate by weight, given at the rate of one ounce twice a day for one week before and one week after farrowing may be helpful.
Being able to prevent, recognize and treat mastitis could help you avoid milk production problems in the future.