Table 2.

Effect of time from last meal until the onset of farrowing (TLMUOF) on farrowing duration adjusted for litter size, mean piglet BW at birth (BWB), and farrowing assistance

Items	Estimate	SEM	P-value	LCL1	UCL1
Intercept2	−3.60	1.54	0.06	−7.34	0.16
Break point	3.13	0.34	< 0.001	2.30	3.97
TLMUOF3	1.14	0.10	< 0.001	0.90	1.38
Litter size	0.21	0.04	0.003	0.10	0.32
BWB	2.72	0.74	0.01	0.91	4.54
Farrowing assistance4	0.72	0.32	0.06	−0.05	1.50

¹LCL = lower confidence limit and UCL= upper confidence limit.

²The mean farrowing duration before the break point (shown in Figure 1) is 3.8 h and can be derived as follows: −3.60 + 0.21 × average litter size + 2.72 × average BWB + 0.24 × 0.72 (see footnote 4).

³The estimate of 1.14 indicates the slope after the breakpoint (shown in Figure 1).

⁴Twenty-four percent of the farrowings received farrowing assistance, and this estimate shows that farrowing duration on average was prolonged 0.72 h when farrowing assistance was required.