Table 1.

Phenotypic variances and proportions of phenotypic variance explained by dam, service sire, and maternal effects for total number born (TNB) and number born alive as a proportion of TNB (NBA/TNB), with standard errors in parentheses

Parameter		TNB	NBA/TNB
Phenotypic variance	${\mathrm{\sigma }}_p^2$	9.218	0.014
Dam (genetic)	${\mathrm{\sigma }}_u^2$/${\mathrm{\sigma }}_p^2$	0.097 (0.003)	0.115 (0.008)
Service sire	${\mathrm{\sigma }}_v^2$/${\mathrm{\sigma }}_p^2$	0.053 (0.053)	0.023 (0.002)
Dam (non-genetic)	${\mathrm{\sigma }}_w^2$/${\mathrm{\sigma }}_p^2$	0.071 (0.003)	0.000 (0.000)

The phenotypic variance was estimated as ${\mathrm{\sigma }}_p^2={\mathrm{\sigma }}_u^2+{\mathrm{\sigma }}_v^2+{\mathrm{\sigma }}_w^2+{\mathrm{\sigma }}_{\mathrm{\epsilon }}^2$