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Maternal and foetal heart rates during exercise in horses

Published online by Cambridge University Press:  02 June 2009

Robert A. Lehnhard ,
Hélio C. Manso Filho ,
Robert C. Causey ,
Malcolm Watford  and
Kenneth H. McKeever
Robert A. Lehnhard
Affiliation:
Department of Exercise Science, University of Maine, Orono, ME, USA
Hélio C. Manso Filho
Affiliation:
Department of Animal Sciences, Equine Science Center, Rutgers the State University of New Jersey, New Brunswick, NJ08901, USA Federal Rural University of Pernambuco, Recife52171-900, Pernambuco, Brazil
Robert C. Causey
Affiliation:
Department of Exercise Science, University of Maine, Orono, ME, USA
Malcolm Watford
Affiliation:
Department of Nutritional Sciences, Rutgers the State University of New Jersey, New Brunswick, NJ08901, USA
Kenneth H. McKeever*
Affiliation:
Department of Animal Sciences, Equine Science Center, Rutgers the State University of New Jersey, New Brunswick, NJ08901, USA
*
*Corresponding author: mckeever@aesop.rutgers.edu
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Abstract

This study tested two hypotheses. First, that moderate exercise would alter maternal and foetal heart rate (HR) in the horse. Second, that pregnancy would alter the HR, plasma cortisol and plasma lactate response to moderate exercise in mares. Six unfit, pregnant Standardbred mares (6–19 years) underwent two incremental graded exercise tests (GXT). The first GXT was performed at approximately 9 months of gestation, which represents c. 80% of the total pregnancy time, and the second GXT at approximately 6 months post-parturition. During the GXT, mares ran on a treadmill up a fixed 6% incline completing three 1 min steps at velocities of 4, 6 and 7 m s− 1. Maternal HR was obtained via both electrocardiograph (ECG) and the ventricular waveform obtained from a micromanometer catheter. Data were recorded at rest, at 4, 6 and 7 m s− 1 of the GXT and at 0, 1, 2, 3, 4 and 5 min post-GXT. Foetal HR rate was measured via ECG before, immediately after and at 1, 2, 3, 4 and 5 min post-GXT. Radioimmunoassay (RIA) kits were used to measure plasma cortisol concentration in samples collected before the GXT, immediately after exercise and after 5 min of recovery. Plasma lactate concentrations (LA) were measured at rest, at 4, 6 and 7 m s− 1 and at 5 min post-GXT. Plasma cortisol concentrations were measured using RIA and the samples collected at rest, immediately after and at 5 min post-GXT. Exercise caused no change (P>0.05) in foetal HR. Maternal HR, plasma LA and plasma cortisol concentration were greater (P < 0.05) during the post-parturient GXT compared with the pre-parturition GXT. Body weight (mean ± SE) was lower after parturition (570 ± 20 vs. 505 ± 22 kg; P < 0.05). Consequentially, there were differences (P < 0.05) in work rate (watts) at each step of the GXT (1557 ± 53 vs. 1381 ± 60; 2339 ± 80 vs. 2071 ± 90; and 2571 ± 121 vs. 2416 ± 105 W). These data suggest that mares benefit from greater cardiovascular efficiency during pregnancy. Additionally, the lack of a change in foetal HR suggests that the unborn foal is not stressed during moderate maternal exercise.

Keywords

horseheart rateexercisepregnancycortisollactate
Type
Research Paper
Information
Comparative Exercise Physiology , Volume 6 , Issue 1 , February 2009 , pp. 43 - 48
Copyright
Copyright © Cambridge University Press 2009

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References

1 England, GCW (2005). Normal pregnancy. Fertility and Obstetrics in the Horse. 3rd edn., Chapter 7. Oxford, UK: Blackwell Publishing, pp. 60–70.CrossRefGoogle Scholar
2 Vaala, WE, Marr, CM, Maxson, AD and Sertich, PL (1995). Perinatology. In: Higgins, AJ and Wright, IM (eds) The Equine Manual. Chapter 14, Philadelphia, PA: Saunders, pp. 639–659.Google Scholar
3 Silver, M and Fowden, AB (1995). Sympathoadrenal and other endocrine and metabolic responses to hypoglycaemia in the fetal foals during late gestation. Experimental Physiology 80: 651–662.CrossRefGoogle ScholarPubMed
4 Silver, M (1984). Some aspects of equine placental exchange and foetal physiology. Equine Veterinary Journal 16: 227–233.CrossRefGoogle ScholarPubMed
5 Taylor, PM, Silver, M and Fowden, AL (1992). Intravenous catheterisation of foetus and mares in late pregnancy: management and respiratory, circulatory and metabolic effects. Equine Veterinary Journal 24: 391–396.CrossRefGoogle Scholar
6 Pomerance, JJ, Gluck, L and Lynch, VA (1974). Physical fitness in pregnancy: its effect on pregnancy outcome. American Journal of Obstetrics and Gynecology 119: 867–876.CrossRefGoogle ScholarPubMed
7 Artal, R, Platt, LD, Sperling, M, Kammula, RK, Jilek, J and Nakamura, R (1981). Maternal cardiovascular and metabolic responses in normal pregnancy. American Journal of Obstetrics and Gynecology 140: 123–127.CrossRefGoogle ScholarPubMed
8 Rauramo, I, Andersson, B, Laatikainen, T and Pettersson, J (1982). Stress hormones and placental steroids in physical exercise during pregnancy. British Journal of Obstetrics and Gynaecology 89: 921–925.CrossRefGoogle ScholarPubMed
9 Hall, DC and Kaufmann, DA (1987). Effects of aerobic and strength conditioning on pregnancy outcomes. American Journal of Obstetrics and Gynecology 157: 1199–1203.CrossRefGoogle ScholarPubMed
10 Kardel, KR and Kase, T (1998). Training in pregnant women: effects on fetal development and birth. American Journal of Obstetrics and Gynecology 178: 280–286.CrossRefGoogle ScholarPubMed
11 Rice, PL and Fort, IL (1991). The relationship of maternal exercise on labor, delivery and health of the newborn. Journal of Sports Medicine and Physical Fitness 31: 95–99.Google ScholarPubMed
12 Carpenter, MW, Sady, SP, Hoegsberg, B, Sady, MA, Haydon, B, Cullinane, EM, Coustan, DR and Thompson, PD (1988). Fetal heart rate response to maternal exertion. Journal of the American Medical Association 259: 3006–3009.CrossRefGoogle ScholarPubMed
13 Jovanovic, L, Kessler, A and Peterson, CM (1985). Human maternal and fetal response to graded exercise. Journal of Applied Physiology 58: 1719–1722.CrossRefGoogle ScholarPubMed
14 Bell, R and O'Neill, M (1994). Exercise and pregnancy: a review. Birth 21: 85–95.CrossRefGoogle ScholarPubMed
15 Webb, KA, Wolfe, LA and McGrath, MJ (1994). Effects of acute and chronic maternal exercise on fetal heart rate. Journal of Applied Physiology 77: 2207–2213.CrossRefGoogle ScholarPubMed
16 Wolfe, LA and Weissgerber, TL (2003). Clinical physiology of exercise in pregnancy: a literature review. Journal of Obstetrics and Gynaecology Canada 25: 473–483.CrossRefGoogle ScholarPubMed
17 Sady, MA, Haydon, BB, Sady, SP, Carpenter, MW, Thompson, PD and Coustan, DR (1990). Cardiovascular response to maximal cycle exercise during pregnancy and at two and seven months post partum. American Journal of Obstetrics and Gynecology 162: 1181–1185.CrossRefGoogle ScholarPubMed
18 Sady, SP and Carpenter, MW (1989). Aerobic exercise during pregnancy. Special considerations. Sports Medicine 7: 357–375 Review.CrossRefGoogle ScholarPubMed
19 Sady, SP, Carpenter, MW, Thompson, PD, Sady, MA, Haydon, B and Coustan, DR (1989). Cardiovascular response to cycle exercise during and after pregnancy. Journal of Applied Physiology 66: 336–341.CrossRefGoogle Scholar
20 Carpenter, MW, Sady, SP, Sady, MA, Haydon, B, Coustan, DR and Thompson, PD (1990). Effect of maternal weight gain during pregnancy on exercise performance. Journal of Applied Physiology 68: 1173–1176.CrossRefGoogle ScholarPubMed
21 Causey, RC, Lehnhard, RA, Finucane, KA and Oliver, TM (2005). Effects of exercise on maternal and foetal heart rate in pregnant mares. Equine and Comparative Exercise Physiology 2: 225–228.CrossRefGoogle Scholar
22 McKeever, KH and Malinowski, K (1999). Endocrine response to exercise in young and old female horses. Equine Veterinary Journal Supplement 30: 561–566.CrossRefGoogle Scholar
23 Freestone, JF, Wolfsheimer, KJ, Kamerling, SG, Church, G, Hamra, J and Bagwell, C (1991). Exercise induced hormonal and metabolic changes in Thoroughbred horses: effects of conditioning and acepromazine. Equine Veterinary Journal 23: 219–223.CrossRefGoogle ScholarPubMed
24 Fowden, AL, Taylor, PM, White, KL and Forhead, AJ (2000). Ontogenic and nutritionally induced changes in fetal metabolism in the horse. Journal of Physiology 528(1): 209–219.CrossRefGoogle ScholarPubMed
25 Lindsay, JR and Nieman, LK (2005). The hypothalamic–pituitary–adrenal axis in pregnancy: challenges in disease detection and treatment. Endocrine Reviews 26: 775–799.CrossRefGoogle ScholarPubMed
26 McCarthy, RN, Jeffcott, LB, Funder, JW, Fullerton, M and Clarke, IJ (1991). Plasma beta-endorphin and adrenocorticotrophin in young horses in training. Australian Veterinary Journal 68: 359–361.CrossRefGoogle ScholarPubMed
27 Jimenez, MA, Hinchcliff, KW and Farris, JW (1993). Catecholamine and cortisol responses of horses to incremental exertion. Veterinary Research Communications 22: 107–118.CrossRefGoogle Scholar
28 Nagata, S, Takeda, F, Kurosawa, M, Mima, K, Hiraga, A, Kai, M and Taya, K (1999). Plasma adrenocorticotropin, cortisol and catecholamines response to various exercises. Equine Veterinary Journal Supplement 30: 570–574.CrossRefGoogle Scholar
29 Golland, LC, Evans, DL, Stone, GM, Tyler-McGowan, CM, Hodgson, DR and Rose, RJ (1999). Plasma cortisol and beta-endorphin concentrations in trained and over-trained Standardbred racehorses. Pflugers Archive 439: 11–17.Google ScholarPubMed
30 McKeever, KH and Gordon, ME (2008). Endocrine alterations in the equine athlete. In: Hinchcliff, KW, Kaneps, A and Geor, R (eds) Equine Exercise Physiology. Chapter 5.2. Philadelphia, PA: Elsevier, pp. 278–304.Google Scholar
31 Malinowski, K, Shock, E, Roegner, V, Rochelle, P, Kearns, CF, Guirnalda, PD and McKeever, KH (2006). Plasma β-endorphin, cortisol, and immune responses to acute exercise are altered by age and exercise training in horses. Equine Veterinary Journal Supplement 36: 2267–2273.Google Scholar
32 Gordon, ME, McKeever, KH, Betros, CL and Manso Filho, HC (2007). Exercise-induced alterations in plasma concentrations of ghrelin, adiponectin, leptin, glucose, insulin, and cortisol in horses. The Veterinary Journal 173: 532–540.CrossRefGoogle ScholarPubMed
33 Lassourd, V, Gayrard, V, Laroute, V, Alvinerie, M, Benard, P, Courtot, D and Toutain, PL (1996). Cortisol disposition and production rate in horses during rest and exercise. American Journal of Physiology 271: R25–R33.Google ScholarPubMed
34 Bruin, G, Kuipers, H, Keizer, HA and Vander Vusse, GJ (1994). Adaptation and overtraining in horses subjected to increasing training loads. Journal of Applied Physiology 76: 1908–1913.CrossRefGoogle ScholarPubMed
35 Toutain, PL, Lassourd, V, Popot, MA, Laroute, V, Alvinerie, M and Bonnaire, Y (1995). Urinary cortisol excretion in the resting and exercising horse. Equine Veterinary Journal Supplement 18: 457–462.CrossRefGoogle Scholar
36 Alexander, SL, Irvine, CH, Ellis, MJ and Donald, RA (1991). The effect of acute exercise on the secretion of corticotropin-releasing factor, arginine vasopressin, and adrenocorticotropin as measured in pituitary venous blood from the horse. Endocrinology 128: 65–72.CrossRefGoogle ScholarPubMed
37 Marc, M, Parvizi, N, Ellendorff, F, Kallweit, E and Elsaesser, F (2000). Plasma cortisol and ACTH concentrations in the warmblood horse in response to a standardized treadmill exercise test as physiological markers for evaluation of training status. Journal of Animal Science 78: 1936–1946.CrossRefGoogle ScholarPubMed