• In 1958, Cargill designs a system that provides sows with a better birthing experience and improves the health and longevity of newborn piglets.
  • The Pigloo allows sows to birth without assistance. Afterward, the baby pigs move to the center, where a lamp lends warmth and bars protect them from being crushed.
  • Inside the Pigloo, the litter is isolated from other animals, protecting them from the possible spread of disease and allowing them to develop antibodies.
  • With the innovative system, piglet mortality rates drop and average weights go up. At two months old, babies born in Pigloos weigh 6 to 10 pounds more than those raised in popular housing.
  • The Pigloo’s success inspires Cargill to apply the same thinking to the dairy industry, introducing the Calfloo system to reduce disease-related deaths among calves.

Pigloos help baby pigs prosper


A new system shields piglets from disease and other dangers, while offering hog farms a more profitable way to produce pork.

When Cargill acquired Nutrena Mills, Inc., in 1945, it significantly expanded its animal feed portfolio. Nutrena was a pioneer in the animal nutrition business, producing a variety of scientifically blended feeds that offered better nutrition for animals, including hogs. By the mid-1950s, Cargill noticed a troubling trend across hog farms: they were losing newborn piglets due to accidents within birthing pens and diseases passed between animals. The trend inspired Cargill to develop an innovative isolation system based on prior research—one that would offer safer settings for newborn piglets and, in effect, a more profitable system for hog farmers.

The Pigloo system was first revealed on April 16, 1958. It quickly gained industry attention, described as “likely to revolutionize the present hog-raising methods.” Built with wood, the structure featured a unique, 12-sided design, much like an igloo. It allowed sows to lie with their backs against the wall and their udders facing a metal guard, safely isolating the sow for a natural birth without need for human assistance. Newborn piglets were then coaxed toward an electric heat lamp to find warmth, distanced from their mother who could accidentally crush them. When the piglets needed milk, they nursed from beneath the metal guard, ensuring continued safety. And because each Pigloo housed a single litter, the baby pigs were shielded from possible diseases spread by other animals. The isolation also afforded them the opportunity to build up their own antibodies, further protecting them from illness.

After the Pigloo’s initial development, Cargill performed preliminary testing over the course of three years with approximately 5,000 animals. The results proved promising: mortality rates from crushing dropped from 14% to less than 2%, and deaths related to disease fell from 10% to almost zero. Additionally, piglets born and raised using Pigloos weighed several pounds more after their first two months than those raised in popular housing. Pigloos helped pork producers with a base of about 120 sows reduce their initial investment in facilities, increase productivity, decrease labor, enhance profits and make larger supplies of pork available to consumers.

Recognizing the success of Pigloos, Cargill sought to apply the same idea to another important industry: dairy. At the time, one-fifth of the company’s newborn cows were dying from contracted diseases. With the Calfloo system, Cargill was able to isolate calves for the first three months of their lives, sharply decreasing their exposure to harmful parasites and reducing disease-related deaths from the national average of 20% to less than 5%.

Today, Cargill continues to be a leader in the pork industry, meeting the evolving demands of both customers and consumers. Recently, there has been growing concern about confining pregnant sows to small spaces for the duration of their pregnancy—a practice that differs from the Pigloo system, which waits to isolate pigs until they are close to giving birth. A majority of Cargill’s operations are now much larger in scale and feature advanced technologies in place of Pigloos and Calfloos. In response to industry concerns, the company is also vowing to achieve 100% group housing for pregnant sows by 2016 and is requiring its contract hog farms to make the same change by 2018.