Faecal Glucocorticoid Metabolites and H/L Ratio Are Related Markers of Stress in Semi-Captive Asian Timber Elephants
Abstract
:Simple Summary
Abstract
1. Introduction
2. Materials and Methods
2.1. Study Population
2.2. Study Outline
2.3. Physiological Markers of Stress
2.3.1. Faecal Sample Collection and FGM Analysis
2.3.2. Blood Smear Preparation and Heterophils/Lymphocytes Ratio
2.4. Body Weight
2.5. Statistical Analysis
3. Results
3.1. Minima, Maxima and Averages of FGM Concentrations and H/L Ratios
3.2. The General Correlation between H/L Ratio and FGM Concentrations
3.3. Correlations between H/L Ratio and FGM Concentrations Depending on Sex
3.4. Correlations between H/L Ratio and FGM Depending on Age Classes
3.5. Correlations between H/L Ratio and FGM Concentrations Depending on Season
3.6. FGM Concentrations and H/L Ratio and Their Links to Body Weight
4. Discussion
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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FGM Concentration (ng/g)/H/L Ratio | ||||
---|---|---|---|---|
Minimum | Average | Maximum | ||
Sex | male | 24.0/0.363 | 78.9/1.05 | 195/2.79 |
female | 19.6/0.296 | 71.5/1.08 | 162/2.53 | |
Age | taming | 24.30/0.363 | 80.0/1.05 | 195/2.79 |
training | 22.9/0.296 | 73.9/1.09 | 162/2.28 | |
working | 25.8/0.323 | 65.6/1.01 | 142/2.23 | |
retired | 19.6/0.371 | 63.3/1.23 | 143/2.53 | |
Season | hot | 19.6/0.296 | 66.8/0.976 | 195/2.53 |
monsoon | 44.9/0.488 | 91.6/0.975 | 158/2.17 | |
cold | 24.3/0.425 | 81.5/1.31 | 150/2.79 |
Parameter | Variable | F | DF | p-Value |
---|---|---|---|---|
Model 1 | ||||
FCM | H/L | 6.06 | 1, 186 | 0.0147 |
sex | 8.38 | 1, 121 | <0.01 | |
origin | 13.5 | 1, 121 | <0.001 | |
season | 15.0 | 2, 186 | <0.0001 | |
age | 0.163 | 3, 186 | 0.921 | |
Model 2 | ||||
FCM | H/L | 6.34 | 1, 185 | <0.01 |
sex | 7.92 | 1, 121 | <0.01 | |
origin | 13.3 | 1, 121 | <0.001 | |
season | 15.0 | 2, 185 | <0.0001 | |
age | 0.171 | 3, 185 | 0.916 | |
H/L*sex | 0.570 | 1, 185 | 0.451 | |
Model 3 | ||||
FCM | H/L | 6.11 | 1, 183 | <0.01 |
age | 4.28 | 3, 183 | <0.01 | |
sex | 3.64 | 1, 121 | 0.0586 | |
origin | 7.19 | 1, 121 | <0.01 | |
season | 14.4 | 2, 183 | <0.0001 | |
H/L*age | 0.817 | 3, 183 | 0.486 | |
Model 4 | ||||
FCM | H/L | 2.32 | 1, 184 | 0.130 |
season | 19.9 | 2, 184 | <0.0001 | |
origin | 8.28 | 1, 121 | <0.01 | |
sex | 7.27 | 1, 121 | <0.01 | |
age | 0.162 | 3, 184 | 0.922 | |
H/L*season | 0.246 | 2, 184 | 0.782 | |
Model 5 | ||||
Standardised body weight | FCM | 7.14 | 1, 80 | 0.00920 |
season | 2.02 | 2, 80 | 0.139 | |
sex | 0.0927 | 1, 110 | 0.761 | |
age | 0.876 | 3, 80 | 0.457 | |
origin | 0.000800 | 1, 110 | 0.977 |
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Seltmann, M.W.; Ukonaho, S.; Reichert, S.; Dos Santos, D.; Nyein, U.K.; Htut, W.; Lummaa, V. Faecal Glucocorticoid Metabolites and H/L Ratio Are Related Markers of Stress in Semi-Captive Asian Timber Elephants. Animals 2020, 10, 94. https://doi.org/10.3390/ani10010094
Seltmann MW, Ukonaho S, Reichert S, Dos Santos D, Nyein UK, Htut W, Lummaa V. Faecal Glucocorticoid Metabolites and H/L Ratio Are Related Markers of Stress in Semi-Captive Asian Timber Elephants. Animals. 2020; 10(1):94. https://doi.org/10.3390/ani10010094
Chicago/Turabian StyleSeltmann, Martin W., Susanna Ukonaho, Sophie Reichert, Diogo Dos Santos, U Kyaw Nyein, Win Htut, and Virpi Lummaa. 2020. "Faecal Glucocorticoid Metabolites and H/L Ratio Are Related Markers of Stress in Semi-Captive Asian Timber Elephants" Animals 10, no. 1: 94. https://doi.org/10.3390/ani10010094