Influence of breeding experience on the sexual behavior of Criollo stallions during semen collection with an estrous mare

Santos, Fernanda Carlini Cunha dos; Nogueira, Carlos Eduardo Wayne; Curcio, Bruna da Rosa

doi:10.1590/0103-8478cr20250394

Stallion sexual behavior is modulated by factors such as the seasonality, handling, age, and sexual experience, and the behavioral patterns observed during semen collection differ from those during natural mating. This study characterized the sexual behavior of Criollo stallions during semen collection and compared the precopulatory and copulatory behavior responses between inexperienced and experienced. Fifty-five stallions were evaluated including reaction time, mount time, mount to ejaculation time, mounts without erection or ejaculation, Flehmen’s response, sniffing, biting, kicking, and vocalizations. The animals were classified as inexperienced (≤ 4 years, n=14) or experienced (5-16 years, n=41). Subsequently, experienced were also subdivided by age (5-8, 9-12, and 13-16 years). Statistical analyses included the Wilcoxon test, Kruskal-Wallis, analysis of variance, and Tukey’s test (P < 0.05). Inexperienced stallions exhibited significantly longer reaction (47.5 ± 31.9 s) and mount times (85.8 ± 56.3 s) than experienced (21 ± 8.1 s and 34.3 ± 11.6 s, respectively), whereas mount to ejaculation duration (~35 s) did not differ between groups. Subdivision of experienced showed that reaction and mount time significantly decreased with age, whereas mount to ejaculation interval were similar across three age groups. The most consistent precopulatory behaviors were vocalization and sniffing, regardless of sexual experience. Inexperienced stallions tended to require multiple mounts more often to achieve ejaculation. In conclusion, breeding experience influenced the behavioral patterns of Criollo stallions during semen collection with an estrous mare, resulting in shorter collection times in experienced stallions. Criollo stallions exhibited typical precopulatory and copulatory behaviors.

Key words:
behavioral assessment; copulatory; precopulatory; reproductive behavior; sexual arousal; sexual maturity.

[TFN1] ^*Parameters expressed in seconds.

[TFN2] ^a,b Indicates significant difference between inexperienced and experienced stallions.

	Inexperienced (n=14)	Experienced (n=41)
Reaction time	47.5 ± 31.9^a	21 ± 8.1^b
Mount time	85.8 ± 56.3^a	34.3 ± 11.6^b
Mount and ejaculation time	34.8 ± 5.3^a	35.8 ± 3.5^a

	5-8y (n=12)	9-12y (n=15)	13-16y (n=14)
Reaction time	27.5 ± 5.9^a	10 ± 1.4^b	10.5 ± 1.9^b
Mount time	48.3 ± 13^a	22.9 ± 2.7^b	18.9 ± 3.8^b
Mount and ejaculation time	36.4 ± 1.8^a	36.1 ± 1.2^a	34.6 ± 1.6^a

	Inexperienced (n=14)	Experienced (n=41)
Sniffing	100	70.7
Vocalizations	100	95.1
Flehmen response	0	12.2
Biting	64.3	19.5
Kicking	0	12.2
Mount without erection	0	0
One mount without ejaculation	35.7	19.5
Two mounts without ejaculation	14.2	12.2
Three mounts without ejaculation	0	2.4

Influence of breeding experience on the sexual behavior of Criollo stallions during semen collection with an estrous mare

Influência da experiência reprodutiva no comportamento sexual de garanhões Crioulos durante a coleta de sêmen com égua em cio