Table 1.

Average fixed effects of Improvest [immunologically castrated barrows (IC)– physically castrated barrows (PC)] on whole and trimmed primal cut-out values from a summary of previously reported data¹

Item	IC	PC	Effect IC- PC	95% CI	SED	P-value
Studies, n	7	6
Carcasses, n	511	320
HCW, kg	96.26	96.25	0.01	(−3.27, 3.31)	3.57	0.99
Chilled side wt, kg	46.22	46.19	0.03	(−1.97, 2.03)	2.15	0.98
Estimated lean, %	53.18	52.60	0.58	(−0.40, 1.55)	0.47	0.29
Lean cutting yield, %2	70.89	69.50	1.39	(0.88, 1.90)	0.24	< 0.01
Carcass cutting yield, %3	86.80	85.56	1.24	(0.62, 1.85)	0.31	0.02
Whole ham, kg	11.49	11.38	0.11	(−0.26, 0.50)	0.41	0.56
% chilled side wt	24.67	24.43	0.24	(−0.23, 0.71)	0.23	0.34
Trimmed ham, kg	9.85	9.56	0.29	(−0.02, 0.60)	0.33	0.11
% chilled side wt	21.36	20.74	0.62	(0.13, 1.12)	0.24	0.05
Trimmed loin, kg	10.65	10.47	0.18	(−0.23, 0.60)	0.48	0.40
% chilled side wt	22.19	21.86	0.33	(−0.11, 0.78)	0.22	0.19
Boston butt, kg	4.21	4.02	0.19	(0.03, 0.36)	0.18	0.05
% chilled side wt	9.14	8.69	0.45	(0.19, 0.69)	0.12	0.01
Picnic shoulder, kg	5.11	4.93	0.18	(−0.06, 0.42)	0.26	0.17
% chilled side wt	10.76	10.38	0.38	(0.14, 0.63)	0.12	0.02
Spareribs, kg	1.79	1.71	0.08	(−0.03, 0.18)	0.11	0.18
% chilled side wt	3.71	3.59	0.12	(0.00, 0.24)	0.06	0.10
Natural fall belly, kg	7.58	7.69	−0.11	(−0.39, 0.17)	0.31	0.45
% chilled side wt	15.50	15.80	−0.30	(−0.61, 0.01)	0.15	0.10

¹Sources include Boler et al. (2011a, 2012, and 2014), Lowe et al. (2014, 2016b), Tavárez et al. (2014), and Harris (2014).

²Lean cutting yield = [(whole ham + trimmed loin + Boston butt + picnic + spareribs)/chilled side wt] × 100.

³Carcass cutting yield = [(lean cutting yield components + natural fall belly)/chilled side wt] × 100.