Plasticity in growth of farmed and wild Atlantic salmon: is the increased growth rate of farmed salmon caused by evolutionary adaptations to the commercial diet?

Table 3 Model selection of the linear mixed effect model used to investigate the influence of diet treatment, genetic group and egg size upon body weight of Atlantic salmon at termination

Model	N	Response Variable	Random effects				Fixed effects
Model	N	Response Variable	Variable	Chi.sq	Chi.df	P	Variable	Sum.sq	Num.df	Den.df	F	P
	1972	Log Weight	T:r	0.54	1	0.46	T x G	0.068	4	11.30	0.52	0.72
			T/G:f	85.06	5	<1e-07	G x E	0.094	2	9.22	1.46	0.28
							T x E	0.25	2	13.01	3.74	0.052
							T	41.76	2	13.80	645.12	<1e07
							G	6.85	2	11.56	105.35	<1e07
							E	0.34	1	11.92	10.29	0.0076

Significance levels of random and fixed effects included in the full LME model investigating variation in log body weight at termination. N; number of individuals. Log weight; log10 (wet weight + 1) at termination. Random effects: T:r; replicate (r) nested within treatment (T) (random intercept). T/G:f; familiy (f) nested within group (G), across treatments (T) (random intercept and slope). Chi.sq; the value of the Chi square statistics. Chi Df; the degrees of freedom for the test. P; P-value of the likelihood ratio test for the random effect. Fixed effects: T, diet treatment (control, carp, natural). G; genetic group (farmed, wild, hybrid). E; mean family (log10) centred egg diameter. Two-way interactions terms included in the full model: T x G, T x E and G x E. Sum.Sq; sum of squares. Num Df, numerator degrees of freedom. Den Df; denominator degrees of freedom based on Sattherwaithe’s approximations. F; F-value. The variables in bold were retained in the final model

ISSN: 2730-7182