| Literature DB >> 34944127 |
Jadwiga Topczewska1, Wanda Krupa2, Zofia Sokołowicz1, Jadwiga Lechowska1.
Abstract
The aim of the study was to determine whether experience related to horse age and number of starts in championships influences stress level, measured by salivary cortisol concentration. The study involved 18 clinically healthy Hucul mares who participated in the Polish Championships for Hucul Horses. Evaluation of performance value was carried out in accordance with the guidelines specified in the breeding and genetic resources conservation program for this breed. The championship lasted two days, consisting of conformation evaluation, endurance, and Hucul path. Saliva was collected at baseline (T1), after arena assessment (T2), after endurance (T3), and on the second day after the Hucul path (T4). Cortisol levels increased from an average of 2.73 ± 1.18 ng/mL (T1) to 10.46 ± 8.03 ng/mL after T3. Significantly lower levels of free cortisol were detected in the saliva of the younger mares, up to 9 years old, and mares who participated in only one qualifying path after each element of the championship. The highest levels of cortisol (T3) were found in mares competing repeatedly on the qualifying path. No correlation was found between cortisol levels and the championship results. Participation of mares in the championship was associated with stress, which was reflected in the increase in cortisol levels in saliva.Entities:
Keywords: horses; performance assessment; saliva cortisol; stress response
Year: 2021 PMID: 34944127 PMCID: PMC8697891 DOI: 10.3390/ani11123345
Source DB: PubMed Journal: Animals (Basel) ISSN: 2076-2615 Impact factor: 2.752
Figure 1A diagram showing the order of competition during the Polish Championships for Hucul Horse in 2019.
Cortisol level relative to mares’ age (ng/mL).
| Mares | T1 | T2 | T3 | T4 | ||
|---|---|---|---|---|---|---|
| Total | n | 18 | 18 | 18 | 18 | |
| mean ± SD | 2.73 ± 1.18 | 3.19 ± 1.28 | 10.46 ± 8.03 | 7.10 ± 3.41 | - | |
| range | 0.85–5.10 | 0.86–6.12 | 2.81–29.07 | 3.14–15.15 | - | |
| ≤9 years | n | 9 | 9 | 9 | 9 | |
| mean ± SD | 2.60 ± 1.26 AD | 2.74 ± 1.15 D | 10.40 ± 8.27 C | 6.49 ± 3.03 BC | 0.0001 | |
| V % | 48.5 | 42.0 | 79.5 | 46.7 | ||
| range | 0.85–4.30 | 0.86–4.80 | 3.91–28.72 | 3.14–12.62 | ||
| ≥10 years | n | 9 | 9 | 9 | 9 | |
| mean ± SD | 2.86 ± 1.16 A | 3.64 ± 1.31 ABC | 10.51 ± 8.28 C | 7.71 ± 3.84 B | 0.0010 | |
| V % | 40.5 | 35.9 | 78.8 | 49.8 | ||
| range | 1.47–5.10 | 2.03–6.12 | 2.87–29.07 | 3.35–15.15 | ||
| 0.6571 | 0.1420 | 0.9790 | 0.4671 |
Saliva samples were collected: T1—baseline samples prior to the competition; T2—after breeding assessment; T3—after the endurance–condition test; T4—after the Hucul path. Means in rows marked with different letters statistically differ.
Figure 2Cortisol level in mare saliva taking into account age, median, percentiles and Kruskal–Wallis test (≤9 years of age—KW-H(3.36) = 22.083; p = 0.0001; ≥10 years of age: KW-H(3.36) = 16.1772; p = 0.0010). The variables after the endurance–condition test are characterized by right-handed asymmetry. In contrast, half of the most typical data (box) are characterized by high similarity. Explanations as in Table 1.
Spearman R correlation coefficient and p value; above—up to 9-year-old mares; below—10-year-old and older mares.
| A | T1 | B | T2 | C | D | T3 | E | F | T4 | G | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| A | ns | ns | 0.82 | ns | ns | ns | ns | ns | ns | ns | |
| T1 | ns | ns | ns | ns | ns | ns | ns | −0.81 | ns | ns | |
| B | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| T2 | 0.67 | ns | 0.67 | ns | ns | ns | ns | −0.71 | ns | ns | |
| C | −0.83 | ns | ns | 0.69 | ns | ns | ns | ns | ns | ns | |
| D | 0.76 | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| T3 | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| E | ns | −0.67 | ns | ns | ns | ns | ns | ns | ns | 0.88 | |
| F | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| T4 | ns | 0.67 | ns | ns | ns | ns | 0.67 | ns | ns | ns | |
| G | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns |
A—resting heart rate, T1—cortisol baseline, B-breeding assessment—points, T2—cortisol after breeding assessment, C—endurance condition test—points, D—average speed of endurance condition test, T3—cortisol after endurance condition test, E—Hucul path—points, F—average speed of Hucul path, T4—cortisol after Hucul path, G—the result of the championship—points; ns—no significant relationship.
Cortisol levels in Hucul mare saliva (ng/mL) relative to their number of starts in the qualification paths.
| Number of Starts | T1 | T2 | T3 | T4 | ||
|---|---|---|---|---|---|---|
| ≥2 | n | 12 | 12 | 12 | 12 | |
| mean ± SD | 3.16 ± 1.07 AD | 3.26 ± 1.30 D | 11.99 ± 8.74 C | 7.49 ± 3.87 B | 0.0000 | |
| V % | 33.9 | 39.9 | 72.9 | 51.7 | ||
| range | 1.55–5.10 | 2.03–6.12 | 2.81–29.07 | 3.14–15.15 | ||
| =1 | n | 6 | 6 | 6 | 6 | |
| mean ± SD | 1.87 ± 0.94 A | 3.04 ± 1.35 ABC | 7.38 ± 5.82 C | 6.33 ± 2.36 B | 0.0030 | |
| V % | 50.3 | 44.4 | 78.7 | 37.3 | ||
| range | 0.85–3.44 | 0.86–4.27 | 3.81–18.36 | 3.39–10.34 | ||
| 0.0351 | 0.7715 | 0.3297 | 0.5703 |
Saliva samples were collected: T1—baseline samples prior to the competition; T2—after breeding assessment; T3—after the endurance–condition test; T4—after the Hucul path. Means in rows marked with different letters statistically differ.
Figure 3Free cortisol level in saliva of mares competing in one and more qualifying paths, median, percentiles and Kruskal–Wallis test (one: KW-H(3.24) = 13.94 p = 0.0030; more than one: KW-H(3.48) = 26.2968 p = 0.00001). The variables after the endurance–condition test are characterized by right-handed asymmetry. Explanations as in Table 1.
Spearman R correlation coefficient and p value for number of qualifications; above—1 start; below—2 and more starts.
| A | T1 | B | T2 | C | D | T3 | E | F | T4 | G | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| A | ns | ns | 0.88 | ns | ns | ns | ns | ns | ns | ns | |
| T1 | ns | ns | 0.83 | ns | ns | ns | ns | −0.94 | ns | ns | |
| B | ns | ns | ns | ns | ns | ns | 0.83 | ns | ns | ns | |
| T2 | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| C | ns | ns | ns | −0.96 | ns | ns | ns | ns | ns | ||
| D | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| T3 | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| E | ns | ns | ns | ns | ns | ns | ns | ns | ns | 0.88 | |
| F | ns | ns | ns | ns | ns | ns | ns | ns | ns | ns | |
| T4 | ns | ns | ns | ns | ns | ns | 0.83 | ns | ns | ns | |
| G | ns | ns | ns | ns | 0.80 | ns | ns | ns | ns | ns |
A—resting heart rate, T1—cortisol baseline, B-breeding assessment—points, T2—cortisol after breeding assessment, C—endurance–condition test—points, D—average speed of endurance–condition test, T3—cortisol after endurance–condition test, E—Hucul path—points, F—average speed of Hucul path, T4—cortisol after Hucul path, G—the result of the championship—points; ns—no significant relationship.