Table 7.

Scoring systems for estrus expression of Large white and Mi gilts.

Estrus expression		Standing reflex	Reddening and swelling of the vulva	Mucus discharge from the vulva
Scoring standards	0	No standing reflex for the back-pressure test within 5 min, or weakly exhibits the standing reflex for the back-pressure test after 5 min	White, or no difference with skin color, no swelling	No mucus
	1	Moderately exhibits the standing reflex after the back-pressure test (stands for boar but moves around some) within 5 min	Pink, slightly heavier than the skin color, slight swelling, a little fold	A small amount of mucus, pussy humid, can’t be pulled into filamentous
	2	Strongly exhibits the standing reflex after the back-pressure test (stands firm without any movement)	Red to fuchsia, significantly deeper than the skin color, swelling significantly, no fold, present bullate	Mucus presents transparent to yellow and viscous, can be formed mucus drops in the corner below the vulva, and mucus can be pulled into filamentous