Danish pork producers out-distance U.S. producers in weaned pigs/sow/year performance, fueled in large part by age at weaning.

While U.S. pork producers contemplate boosting weaning age, Danish producers have excelled at the management practice for years.

By stretching the length of the lactation period, the Danes have vastly increased numbers of weaned pigs produced/sow/year (Table 1). The chart reflects the top five breeding herds in Denmark using Danbred genetics.

How They Wean More Pigs

Danish producers are a pig and a half/litter ahead of their American counterparts and wean pigs at 25-30 days of age. Live born pigs/litter can exceed 13.5, while Danbred North America's best customers are achieving 12.0, states Larry Himmelberg, swine nutritionist and director of Customer Support at Danbred North America.

John Waddell, a Sutton, NE, swine veterinarian who consults with Danbred, says the ban on antibiotic growth promoters (AGPs) prompted the Danes to extend weaning age.

“When the ban on AGPs in the nursery phase in Denmark occurred at the start of 2000, there were a lot of farms with enteric problems when weaning pigs,” he notes. “So one of the things they did to get around that was to start weaning older, taking a more robust pig into the nursery.” The next year Europe imposed a ban on weaning under 21 days old.

Table 1. Top Five Danish Breeding Herds Using Danbred Genetics, 2002
Herd Number 1 2 3 4 5
Herd Size 429 661 518 483 216
Pigs weaned/sow/year * 30.5 29.9 29.9 29.4 29.4
Litters/sow 2.38 2.36 2.42 2.40 2.43
Born alive/litter 13.9 14.1 13.3 13.4 12.9
Pigs weaned/litter 12.8 12.8 12.4 12.2 12.1
Age at weaning (days) 30 27 28 28 25
Weight at weaning (lb.) 15.2 15.2 15.4 15.8 16.1
Prewean mortality (%) 7.8 9.0 6.9 8.5 11.0
Farrowing rate (%) 95.1 87.0 93.5 - 90.3


A side benefit the Danes saw from later weaning was that subsequent litters of pigs were bigger (one-tenth of a pig/day of increased weaning age), says Waddell.

Himmelberg says Danbred North America producers have reported like results.

Tom Rathje, Danbred's geneticist, doubts the gains seen in weaned pigs by later weaning are unique to Danbred genetics.

“You are dealing with a lot of factors here, but a couple that stand out is letting the uterus return to normal (after farrowing); you are not forcing the pregnancy before the complete involution of the uterus (return to normalcy) occurs in the sow,” he explains. “More time is also advantageous to reestablishing a normal hormonal pattern and estrous cycle.”

Another factor in the Danes' favor, which has a huge impact on live born, is age at first mating, says Waddell. Danish farmers don't rush to get gilts mated right away.

“If you hold that gilt for another month before she is bred, in her lifetime she may produce way more pigs to make up for 30 non-productive days that we have been afraid we are going to lose by breeding her late,” he states.

They advise gilts should be 230 to 250 days old and at least 320 lb. at first mating.

Himmelberg says some of Danbred's U.S. customers have been able to improve live born averages of Parity 1 females from 10.5 pigs to 11.25. Key to that is breeding gilts older and heavier, he says.

Waddell says Danish producers also delay all boar exposure until gilts reach maturity and move to the breeding barn. This practice enhances gilts' ability to cycle, breed and settle.

Danbred North America is also studying the benefits of foregoing boar exposure until 25-30 days prior to mating.

And the genetics company is urging producers to look at later weaning. The economics of increasing weaning age look especially attractive if postweaning pig performance is improved, in addition to sow productivity, says Himmelberg.

But producers have one other option, says Waddell. “If you wean once a week, you've got a seven-day age spread from the oldest to the youngest pig. If you go to twice-a-week weaning, you narrow that age spread down to 3.5 days, taking off that lower weaning age.”