Photograph of pigs in rows of pig pens illustrating the 'business system' and layout on farms in the early/mid 20th century.

Photograph of several choice pigs in a pen in the late 19th or early 20th century.

Photograph of the exterior of a large hog house showing the pig pens along one side in the early 20th century.

Photograph of covered yards to house in-pig sows at Gogar Mains, Edinburgh, Scotland in 1937.

Photograph of an interior of a barn showing the feeding and sleeping quarters of a piggery in the early/mid 20th century [Seton Mains, 1937?]

Photograph of an interior of a barn showing the feeding and sleeping quarters of a piggery with pigs at Seton Mains, 1937.

Photograph of pigs in several pens on a farm behind a barn. Possibly part of the Survey of India Office, Calcutta, March 1903.

Photograph of several prime heavy hogs in a pen with a group of men standing in the background.

Photograph of a badly kept pen for pigs in a farm yard. With farm buildings in the background, there is a pool of water with broken timber, broken fences and crowded conditions for pigs.

Photograph of a portable house for pigs at the University of Wisconsin Agricultural Experiment Station in the early/mid 20th century.