HOUSING
PIH-55
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
Space Requirements for Swine
Authors
R. D. Fritschen, University of Nebraska
Arthur J. Muehling, University of Illinois
Reviewers
Al H. Jensen, University of Illinois
Ray Stevermer, Easton, Minnesota
The space requirement per pig reared on dirt lots or pasture has previously been given little special attention. However, as confinement production developed, the amount of space needed per pig for optimal performance became an important planning-management consideration. This fact sheet deals with space management in confinement production.
Table 1. Space recommendations for pigs using partial or total slats.	
Pig weight or class	Sq. ft. for partial or total slats
15-30 lb.	1.7-2.5
30-60 lb.	3-4
60-100 lb.	5
100-150 lb.	6
150-market	8*
Gestating sows or gilts	14-16
Boars (developing)	20
Boars (mature)	40
	
*Adjusting pig numbers per pen seasonally may result in improved performance. For example, increasing the number per pen by 1 or 2 pigs during winter may be desirable.
Table 2. Space requirement recommendations for pigs using building with outside apron.	
Pig class	Sq. ft.
Growing-Finishing	6 sq. ft. inside plus 6 sq. ft. outside
Sows	11-12 sq. ft. inside plus 11-12 sq.ft.outside
Boars	40 sq. ft. inside plus 40 sq. ft. outside
General Space Management
Too few pigs per pen reduces the return on initial building investment. However, care must be taken to prevent overcrowding. The results of overcrowding may include tail biting or cannibalism, reduced gain, increased feed required/unit gain, gastric ulcers and/or additive stress factors. Various levels of these, plus others, may cause increased susceptibility to disease or other adverse effects on performance or reproduction.

It is generally impractical to provide the optimal area per pig at all stages of the life cycle. Since, for most phases of life, the pig is continuously increasing in size, the space requirement changes at a similar rate. Movement of pigs from one building to another to provide optimal space has, in at least one study, caused setback in pig performance and health. Moving pigs to larger pens to adjust for increased size may be best accomplished when the move is within a building rather than between buildings, especially for young pigs. For most producers, providing optimal space must be a manageable compromise between adjusting the pen size and/or the number of pigs per pen. Maximizing pen occupancy is perhaps best achieved by utilizing pens of increasing size. Mixing groups of pigs is a somewhat risky method of obtaining optimum occupancy.

Tables 1-3 give space recommendations based upon current research that take into account most factors. (Space recommendations may vary slightly between sources.)
Table 3. Space requirement recommendations for pigs using pasture and shade space.		
Pig class	Pasture	Shade or winter housing
Sows	10 sows/acre	15-20 sq. ft./sow
Sows and titters	7 sows and litters	20-30 sq. ft./sow and litter
Boars	1/4 acre/boar	40-60 sq. ft./boar
Cooperative Extension Work in Agriculture and Home Economics, State of Indiana, Purdue University and U.S. Department of Agricultre Cooperating. H.G. Diesslin, Director,West Lafayette, IN. Issued in furtherance of the Acts of May 8 and June 30, 1914. It is the policy of the Cooperative Extension Service of Purdue University that all persons shall have equal opportunity and access to its programs and facilities without regard to race, color, sex, religion, national origin, age or handicap.