Table 3.

The number of trials (n = 113) by production stage at intervention, type of intervention, and housing group size with citations

Production stage at intervention	Intervention	Pen/paddock size	N	Citations
Cow-calf (n = 7)	Feeding	≤ 15	1	Larson et al., 2009
		Unspecified	2	Mulliniks et al., 2012; Stalker et al., 2006
	Management	Unspecified	3	Karren et al., 1987; Peterson et al., 1989
	Vaccination	Unspecified	1	Kirkpatrick et al., 2008
Cow-calf and backgrounder or stocker (n = 2)	Management	Unspecified	1	Shike et al., 2007
	Multiple	16–50	1	Anderson et al., 2005
Cow-calf and Feedlot (n = 1)	Vaccination	Unspecified	1	Bechtol et al., 1991
Backgrounder or stocker (n = 8)	Feeding	≤ 15	2	Forte et al., 2018; Mir et al., 2008
		Unspecified	3	Parish et al., 2013; Lewis et al., 1990; Bedwell et al., 2008
	Management	Unspecified	3	McCartney et al., 2008
Backgrounder or stocker and Feedlot (n = 5)	Feeding	≤ 15	3	Berthiaume, 2006; Şentürklü et al., 2018; Lewis et al., 1990
		Unspecified	2	Gillespie-Lewis et al., 2016
Feedlot (n = 90)	Feeding	≤ 15	8	Price et al., 1978; Xiong et al., 1991; Bartle et al., 1994; Flatt et al., 2003; Sawyer et al., 2004; Swyers et al., 2014; Loerch and Fluharty, 1998; Hinman et al., 1999
		16–50	2	Rivera et al., 2018
		51–350	6	Gallo and Berg, 1995; Vázquez-Añón et al., 2007; Perrett et al., 2008b; Van Donkersgoed et al., 2011; Van Donkersgoed et al., 2014; Sides et al., 2009
		Unspecified	5	Louis et al., 1988; Dubeski et al., 1997; DeRouen and Foster, 2006
	Management	≤ 151	4	Jim et al., 1991; Elam et al., 2008; Step et al., 2008; Cooprider et al., 2011
		51–3502	4	Edwards and Laudert, 1984; Macken et al., 2003; Blaine and Nsahlai, 2011; Kononoff et al., 2015
		Unspecified	1	Kadel et al., 1985
	Multiple	≤15	5	McEwen et al., 2007; Stanton et al., 1989; Sawyer et al., 2003; Lefebvre et al., 2006
		51–350	2	Macken et al., 2003
	Parasite control	≤15	3	Grimson et al., 1987; Campbell et al., 1987; Williams et al., 1991
		16–50	4	Grimson et al., 1987; Alexander and Miller, 1972
		51–350	6	Flack et al., 1967; Schunicht et al., 2000; MacGregor et al., 2001
		≥351	2	Flack et al., 1967
		Pen size varied	1	Guichon et al., 2000
		Unspecified	5	Bauck et al., 1989; Soll et al., 1991; Leland et al., 1980; Wellington and Van Schalkwyk, 1982
	Parenteral antimicrobial	16–50	1	Hannon et al., 2009
		51–350	17	Mechor et al., 1988; Jim et al., 1992; Jim et al., 1999; Schunicht et al., 2002a; Schunicht et al., 2002b; Booker et al., 2007; Van Donkersgoed et al., 2008a; Van Donkersgoed et al., 2008b; Abutarbush et al., 2012; Van Donkersgoed and Merrill, 2012; Van Donkersgoed et al., 2013; Van Donkersgoed and Hendrick, 2013; Van Donkersgoed and Merrill, 2013a; Van Donkersgoed and Merrill, 2013b; Tennant et al., 2014; Van Donkersgoed et al., 2017
		Pen size varied	3	Booker et al., 2006; Schunicht et al., 2007; Perrett et al., 2008a
		Unspecified	2	Stegner et al., 2013; Booker et al., 1992
	Vaccination	51-350	6	Gummow and Mapham, 2000; Schunicht et al., 2003; Bryant et al., 2008; Perrett et al., 2008c; Wildman et al., 2008; Rogers et al., 2015
		Pen size varied	2	MacGregor and Wray, 2004; Wildman et al., 2009
		Unspecified	1	Bechtol et al., 1991

In one trial (Step et al., 2008), 13–16 animals were housed per pen.

One trial (Kononoff et al., 2015) reported 52 head per pen plus or minus 5.69 head.