Table 3.

Variables included in the final models for self-bite environmental risk factor analysis. Variables with positive beta (ß) estimates positively predict self-bite, variables with negative beta estimates negatively predict self-bite. Categorical variables all have a “referent” variable, the variable to which other levels of the variable are compared. Referent variables do not have beta estimates. For categorical variables all variables compared to the referent are indented. A linear covariate is included in the model for age, however since it is intended to be a covariate and not a predictor it is not reported.

Variable	ß Estimate (SE)	Lower 95% CI	Upper 95% CI
Model 1: Self-bite ~ rearing, sex, years outdoors, cage level, cage position
Rearing – Field Cage	–	–	–
Rearing – Corn Crib	0.08 (1.20)	−2.27	2.43
Rearing – Indoor Mother	1.05 (0.78)	−0.48	2.58
Rearing – Nursery	1.60 (0.63)	0.37	2.83
Sex – Female	–	–	–
Sex – Male	0.82 (0.44)	−0.042	1.68
Years Outdoors	−0.61 (0.16)	−0.92	−0.30
Cage Level - Bottom	–	–	–
Cage Level – Top	−0.34 (0.23)	−0.79	0.11
Cage Position	−0.04 (0.02)	−0.09	0.001
Model 2: Self-bite ~ rearing, sex, years outdoors, pair separations, cage position
Rearing – Field Cage	–	–	–
Rearing – Corn Crib	0.08 (1.18)	−2.24	2.39
Rearing – Indoor Mother	1.11 (0.78)	−0.42	2.64
Rearing – Nursery	1.69 (0.63)	0.46	2.92
Sex – Female	–	–	–
Sex – Male	0.82 (0.44)	−0.04	1.68
Years Outdoors	−0.55 (0.16)	−0.86	−0.24
Pair Separations	0.15 (0.12)	−0.09	0.38
Cage Position	−0.05 (0.02)	−0.09	−0.004
Contrasts
Corn Crib– Field Cage	0.08	−2.27	2.43
Indoor Mother– Field Cage	1.05	−0.48	2.58
Nursery– Field Cage	1.60	0.37	2.83
Indoor Mother– Corn Crib	0.97	−1.45	3.39
Nursery–Corn Crib	1.52	−0.74	3.77
Nursery– Indoor Mother	0.55	−0.60	1.69
Motor stereotypic behavior (MSB) and Self-bite
MSB	0.23 (0.05)	0.13	0.33