Genetic analysis of disease resilience of wean-to-finish pigs under a natural disease challenge model using reaction norms

Table 2 Comparison of slope genetic variances for the linear and cubic reaction norm models for analysis of average daily gain (ADG, g) and treatment rate (TRT) in the challenge nursery (cNur), finisher (Fin) and across the nursery and finisher (All) for six challenge loads based on clinical disease traits or growth rate

Trait	Slope genetic variance (SE) using clinical disease traits			Slope genetic variance (SE) using growth rate
Trait	NurCLc	FinCLc	CLc	NurCLg	FinCLg	CLg
Linear RN
cNurADG	400 (300)	700 (300)	800 (300)	20 (300)	2300 (300)	2200 (400)
FinADG	4000 (700)	1000 (400)	800 (400)	2000 (500)	0	400 (400)
cNurTRT	0	0.10 (0.03)	0.09 (0.03)	NA	0.15 (0.04)	0.13 (0.04)
AllTRT	0.10 (0.05)	0.16 (0.05)	0.21 (0.06)	0.14 (0.05)	0.14 (0.05)	0.31 (0.07)
Cubic RN
cNurADG	700 (400)	900 (300)	1000 (300)	300 (300)	3000 (600)	2000 (400)
FinADG	4000 (600)	1000 (400)	1000 (400)	3000 (600)	800 (400)	1000 (400)
cNurTRT	0	0.11 (0.04)	0.11 (0.04)	0.024 (0.03)	0.15 (0.04)	0.13 (0.04)
AllTRT	0.10 (0.05)	0.19 (0.05)	0.26 (0.06)	0.15 (0.06)	0.14 (0.05)	0.31 (0.07)

All six different CL were fitted as fixed effects in the linear and cubic reaction norm model, but only the corresponding CL was fitted as random animal genetic slope. cNurADG: growth rate in the challenge nursery; FinADG: growth rate in the finisher; cNurTRT: medical treatment rate in the challenge nursery; AllTRT: medical treatment rate across the challenge nursery and finisher; NurCLc: challenge load derived from the clinical disease traits in the challenge nursery; FinCLc: challenge load derived from the clinical disease traits in early finisher; CLc: weighted challenge load of NurCLc and FinCLc; NurCLg: challenge load derived from the growth rate in the challenge nursery; FinCLg: challenge load derived from the growth rate in early finisher; CLg: weighted challenge load of NurCLg and FinCLg; figures in italic characters indicate the greatest genetic slope variance for that trait

ISSN: 1297-9686