{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,12]],"date-time":"2026-10-12T21:04:17Z","timestamp":1791839057505,"version":"4.3.4"},"reference-count":84,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T00:00:00Z","timestamp":1638835200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Humans who care for pigs prefer an environment that not only allows the pigs to express their natural behaviors but also limits the development of aggression and stereotypes. Most of the behavioral and health problems encountered by pigs in barren, conventional conditions are solved by alternative housing systems. However, it is not known whether these systems are advantageous in terms of the performance of pigs. In this work, we review the effects of housing systems on pigs\u2019 behaviors and performance, which are among the major indicators of the welfare of these animals. Research results point out that outdoor systems are more ideal for sows and fatteners than buildings. Nonetheless, outdoor housing is associated with two major effects in both groups: increased activity due to environmental exploration and higher space allowance, and increased incidence of injuries compared to indoor systems. Sows are more active when housed in groups, but they experience an increased frequency of injuries. According to the literature, group-housed sows give birth to healthy piglets with good daily weight gains. The difference in the fattening and slaughter performance of pigs raised indoors vs. outdoors remains unclear, and the results reported so far are inconsistent. Outdoor systems seem to be associated with a higher incidence of osteochondrosis and lesions of elbow and hock joints, whereas indoor systems cause a greater degree of body soiling in pigs. Based on the reviewed literature, it may be concluded that outdoor housing helps to solve behavioral issues in pigs but leads to other problems in pig production.<\/jats:p>","DOI":"10.3390\/ani11123484","type":"journal-article","created":{"date-parts":[[2021,12,7]],"date-time":"2021-12-07T09:52:29Z","timestamp":1638870749000},"page":"3484","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["How Housing Conditions Determine the Welfare of Pigs"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3009-3346","authenticated-orcid":false,"given":"Agnieszka","family":"Ludwiczak","sequence":"first","affiliation":[{"name":"Department of Animal Breeding and Product Quality Assessment, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3904-7925","authenticated-orcid":false,"given":"Ewa","family":"Skrzypczak","sequence":"additional","affiliation":[{"name":"Department of Animal Breeding and Product Quality Assessment, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2626-9329","authenticated-orcid":false,"given":"Joanna","family":"Sk\u0142adanowska-Baryza","sequence":"additional","affiliation":[{"name":"Department of Animal Breeding and Product Quality Assessment, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8943-0266","authenticated-orcid":false,"given":"Marek","family":"Stanisz","sequence":"additional","affiliation":[{"name":"Department of Animal Breeding and Product Quality Assessment, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3179-503X","authenticated-orcid":false,"given":"Piotr","family":"\u015al\u00f3sarz","sequence":"additional","affiliation":[{"name":"Department of Animal Breeding and Product Quality Assessment, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Przemys\u0142aw","family":"Racewicz","sequence":"additional","affiliation":[{"name":"Laboratory of Veterinary Public Health Protection, Pozna\u0144 University of Life Sciences, S\u0142oneczna 1, 62-002 Suchy Las, Poland"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,7]]},"reference":[{"key":"ref_1","unstructured":"FAWC (1993). 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