Stallion Mate Choice and Mare Sexual Behaviour in a Herd of Sorraia Horses (Equus caballus)

Table 2

Influence of dominance status and reproductive state on male mate choice and female receptivity, as measured by the Mann-Whitney U-test.

	Mean ± S.D.	Dominance			Reproductive state
		𝑁D	𝑁S	U	𝑁B	𝑁F	U
2003
Simultaneous oestrus frequency (h^−1)	0.91 ± 0.65	6	2	10	5	3	15*
Total oestrus frequency (h^−1)	0.72 ± 0.45	6	2	10	5	3	15*
Total success (%)	14.9 ± 11.7	7	2	6	6	3	11.5
Success in oestrus (%)	27.8 ± 17.1	6	2	7	5	3	5
Oestrus discrimination (%)	74.3 ± 17.3	6	2	0	5	3	3
Receptivity (%)	55.3 ± 23.0	6	2	10	5	3	8
2005
Simultaneous oestrus frequency (h^−1)	0.86 ± 0.57	6	3	7	6	3	4
Total oestrus frequency (h^−1)	0.87 ± 0.61	7	3	7.5	6	4	10
Total success (%)	10.6 ± 12.9	7	3	10	6	4	10
Success in oestrus (%)	17.2 ± 20.4	7	3	8	6	4	9
Oestrus discrimination (%)	72.9 ± 18.0	7	3	21*	6	4	22*
Receptivity (%)	57.9 ± 23.0	7	3	8	6	4	17

Number of mares: 𝑁_D: dominants, 𝑁_S: subordinates, 𝑁_B: barren and 𝑁_F: with foals; *𝑃<.05.