Influence of transrectal and transabdominal ultrasound examination on salivary cortisol, heart rate, and heart rate variability in mares.
Abstract: Pregnancy diagnostics in equine reproduction are routinely performed using transrectal ultrasonography, although it is also possible to visualize the fetus by transabdominal ultrasound examinations from the 90th day of gestation onward. We hypothesized that ultrasound examinations may stress the mare and that the gestational stage status and lactation may influence the mare's stress reaction. To investigate the stress reaction, 25 thoroughbred mares of different age, pregnancy and lactational status underwent a transrectal examination. In pregnant mares, an additional transabdominal examination was performed. Salivary cortisol concentration, mean heart rate, and heart rate variability of mares were assessed to evaluate the reactions of hypothalamic-pituitary-adrenal (HPA) axis and of the autonomic nervous system. Significant differences were observed between lactating and nonlactating mares; with a lower responsiveness to stress in lactating mares. The transrectal ultrasound examination in nonlactating mares induced a significant increase in salivary cortisol (P < 0.05), and in the heart rate variability parameter, ratio of low to high frequencies (P < 0.05). This reflects an activation of the HPA axis and a shift to more sympathetic dominance. In contrast, a transabdominally performed pregnancy check did not induce an activation of the HPA axis over basal level but increased the mean heart rate and low to high frequency ratio. The results of this study indicate that checks of advanced pregnancies can be easily performed by transabdominal ultrasonography. With regard to animal welfare, this technique should be preferred during midgestation in nonlactating mares.
Copyright © 2015 Elsevier Inc. All rights reserved.
Publication Date: 2014-11-13 PubMed ID: 25529317DOI: 10.1016/j.theriogenology.2014.11.010Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research investigates the effects of transrectal and transabdominal ultrasound examinations on the stress levels of mares using salivary cortisol, heart rate, and heart rate variability. The study concludes that these examinations may cause stress, particularly in non-lactating mares, and suggests performing checks of advanced pregnancies using transabdominal ultrasonography for the sake of animal welfare.
Study Methodology
- Twenty-five thoroughbred mares with varied age, pregnancy, and lactation status were subject to a transrectal examination. Pregnant mares also had an additional transabdominal examination.
- The team evaluated the mares’ hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system based on salivary cortisol concentration, mean heart rate, and heart rate variability.
- The researchers observed the reactions to identify any stress response due to the ultrasound examinations.
Observations and Findings
- The study notes considerable differences between lactating and nonlactating mares. Lactating mares had lower stress responses compared to their non-lactating counterparts.
- Transrectal ultrasound examination in non-lactating mares triggered a significant increase in salivary cortisol and heart rate variability parameter. This indicates activation of the HPA axis and a shift towards more sympathetic dominance, reflecting a stress response.
- On the other hand, transabdominal pregnancy check did not induce HPA axis activation beyond the basal level but boosted the mean heart rate and ratio of low to high frequencies.
Conclusion and Recommendations
- The researchers inferred that the ultrasound examinations, particularly transrectal ones, could be stressful for mares, more so for those that are not lactating.
- It was recommended that checks of advanced pregnancies should be performed using transabdominal ultrasound examinations, especially in non-lactating mares. This technique is proposed to be better for animal welfare.
Cite This Article
APA
Schönbom H, Kassens A, Hopster-Iversen C, Klewitz J, Piechotta M, Martinsson G, Kißler A, Burger D, Sieme H.
(2014).
Influence of transrectal and transabdominal ultrasound examination on salivary cortisol, heart rate, and heart rate variability in mares.
Theriogenology, 83(4), 749-756.
https://doi.org/10.1016/j.theriogenology.2014.11.010 Publication
Researcher Affiliations
- Clinic for Horses-Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany; National Stud Lower Saxony, Celle, Germany.
- Clinic for Horses-Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany.
- Clinic for Horses-Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany.
- Clinic for Horses-Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany.
- Clinic for Cattle, University of Veterinary Medicine Hannover, Hannover, Germany.
- National Stud Lower Saxony, Celle, Germany.
- Thoroughbred Studfarm Harzburg, Bad Harzburg, Germany.
- Swiss Institute of Equine Medicine, Agroscope and University of Berne, Avenches, Switzerland.
- Clinic for Horses-Unit for Reproductive Medicine, University of Veterinary Medicine Hannover, Hannover, Germany. Electronic address: harald.sieme@tiho-hannover.de.
MeSH Terms
- Animals
- Female
- Heart Rate / physiology
- Horses / physiology
- Hydrocortisone / chemistry
- Hydrocortisone / metabolism
- Pregnancy
- Saliva / chemistry
- Ultrasonography / methods
- Ultrasonography / veterinary
Citations
This article has been cited 0 times.Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
