Effect of dietary carbohydrates and time of year on ACTH and cortisol concentrations in adult and aged horses

Jacob, S.; Geor, R. J.; Weber, P.S.D.; Harries, Priscilla; McCue, Molly E.

doi:10.1016/j.domaniend.2017.10.005

Cited by 28 publications

(41 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Nonetheless, the rest of donkeys tested in both farms and considered healthy (without PPID and not included in the study) had ACTH concentrations lower than the cut-off value and those previously described [22][23][24]. Breed, species, age, geographical location, starch-content diet and feeding status, and seasonal or diurnal circadian rhythm have been shown to influence baseline ACTH concentrations in horses [25][26][27][28][29][30][31][32]. Regarding the diet, higher ACTH values have been demonstrated in aged horses feeding a high-starch diet [25].…”

Section: Discussionmentioning

confidence: 94%

“…Breed, species, age, geographical location, starch-content diet and feeding status, and seasonal or diurnal circadian rhythm have been shown to influence baseline ACTH concentrations in horses [25][26][27][28][29][30][31][32]. Regarding the diet, higher ACTH values have been demonstrated in aged horses feeding a high-starch diet [25]. This issue is important when interpreting ACTH concentrations (both basal and after TRH stimulation test) for PPID diagnosis.…”

Section: Discussionmentioning

confidence: 99%

“…Breed, species, age, geographical location, starch‐content diet and feeding status, and seasonal or diurnal circadian rhythm have been shown to influence baseline ACTH concentrations in horses . Regarding the diet, higher ACTH values have been demonstrated in aged horses feeding a high‐starch diet .…”

Section: Discussionmentioning

confidence: 99%

See 2 more Smart Citations

Evaluation of dynamic testing for pituitary pars intermedia dysfunction diagnosis in donkeys

Mejia‐Pereira¹,

Pérez-Écija

Buchanan³

et al. 2018

Equine Veterinary Journal

View full text Add to dashboard Cite

Summary Background Endocrine disorders are common in donkeys. Pituitary pars intermedia dysfunction (PPID) is thought to be a frequent disturbance in donkeys due to their longevity. However, information on PPID dynamic testing in donkeys is lacking. Objectives The objective of this study was to evaluate the previously described guidelines for PPID diagnosis in horses in donkeys with suspicion of PPID. Study design Prospective experimental study. Methods Eighty donkeys were evaluated for PPID suspicion based on clinical signs and baseline adrenocorticotropic hormone (ACTH) concentrations. Six mix‐breed donkeys (one jack and five non‐pregnant jennies) fulfilling inclusion criteria were subjected to dexamethasone suppression test (DST), thyrotropin‐releasing hormone stimulation test (TRH) and combined DST–TRH challenge. Tests were interpreted according to guidelines for PPID diagnosis in horses. Results Donkeys fulfilling inclusion criteria were diagnosed with PPID by TRH stimulation test (six of six). Both DST (three of six) and DST–TRH (4/6) challenges failed to detect those animals and showed conflicting results. Similarly, cortisol basal concentrations were not consistent with PPID suspicion. Main limitations Characterisation of seasonal and geographical location effect on baseline ACTH concentrations and response to TRH is compelling in this species. Further studies with a larger number of donkeys are needed. Conclusions This is the first study in donkeys to evaluate common dynamic tests used for PPID diagnosis in horses. Preliminary results agree with the guidelines for PPID diagnosis in horses and baseline ACTH measurement followed by TRH challenge are recommended tests for diagnosis of PPID in donkeys.

show abstract

Section: Discussionmentioning

confidence: 94%

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Evaluation of dynamic testing for pituitary pars intermedia dysfunction diagnosis in donkeys

Mejia‐Pereira¹,

Pérez-Écija

Buchanan³

et al. 2018

Equine Veterinary Journal

View full text Add to dashboard Cite

show abstract

“…However, the external environment provided by the paddocks could ensure important behaviors and physiological needs [29]. Diet composition and changes in feeding frequency can produce fluctuations in horse hormone patterns, including cortisol [30,31]. Interestingly, cows relocated from their habitual environment, and nutrition conditions had higher HCCs [32].…”

Section: Discussionmentioning

confidence: 99%

Temporary Relocation during Rest Periods: Relocation Stress and Other Factors Influence Hair Cortisol Concentrations in Horses

Gardela

Carbajal

Talló-Parra

et al. 2020

Animals

View full text Add to dashboard Cite

Horse transportation for temporary relocation during rest periods is a common and widespread practice among horse owners, either from sport competition or working tasks. This study aimed to determine the effect of a relocation period and the multiple factors associated with a rest period on hair cortisol concentrations (HCCs) in horses. Additionally, this study reports the seasonal effect on HCCs and hair growth over a year. Thirteen police horses, Pure Spanish stallions of various ages (5–13 y), were selected to participate in this study. Hair sample collection was carried out approximately every 30 d for seven months (Study 1) and a year (Study 2). Cortisol determinations were performed by enzyme immunoassay. Interestingly, Study 1 revealed that relocated horses (n = 4) exhibited elevated HCCs compared with control horses (n = 4) after the relocation period (p < 0.05). Study 2 (n = 5) showed higher HCCs during summer compared with autumn and winter, and higher hair growth rates in winter compared with the other seasons (p < 0.05). Relocated horses had higher HCCs, suggesting a change in their welfare status, probably related to the sudden change in their surrounding conditions. However, these results should be interpreted cautiously due to the low sample size used. The nature of the relationship between HCCs and horse welfare needs to be further examined.

show abstract

“…In cycling mares, studies on the hypothalamic pituitary adrenal (HPA) axis response to stress under different physiological conditions such, transport [1], and gynecological manipulations for artificial insemination [2], pregnancy [3], weaning [4], nutritional imbalances [5], exercise [6], pain [7], and social stress [8] have been widely documented. Stress, inducing an increase of adrenocorticotropic pituitary hormone (ACTH) and cortisol (CORT) responses, exerts negative effects on reproduction; in fact, it suppresses the release of gonadotropin-releasing hormone (GnRH), interferencing with the pulsatility and the peak of luteinizing hormone (LH) and changing the secretion of oestradiol-17β (E2) with a decrease of the sexual behavior, ovulation, and fertility [9].…”

Section: Introductionmentioning

confidence: 99%

Endocrine and Electrolyte Balances during Periovulatory Period in Cycling Mares

Satué

Fazio

Muñoz

et al. 2021

Animals

View full text Add to dashboard Cite

In cycling females, the periovulatory period is characterized by stimulation of the hypothalamic pituitary adrenal (HPA) axis. The aim of present study was to analyze the pattern and interrelationships among adrenocorticotropic hormone (ACTH), cortisol (CORT), aldosterone (ALD) and electrolytes (sodium—Na+, potassium—K+ and chloride—Cl−) during periovulatory period in cycling mares. Venous blood samples were obtained daily from a total of 23 Purebred Spanish broodmares, aged 7.09 ± 2.5 years, from day −5 to day +5 of estrous cycle, considering day 0, the day of ovulation. Plasma ACTH was measured by a fluorescent immunoassay kit, serum CORT and ALD by means of a competitive ELISA immunoassay, and plasma Na+, K+ and Cl− were quantified by an analyzer with selective electrodes for the three ions. ACTH showed higher concentrations at day 0 compared to days −5 to −1 and +1 to +3 (p < 0.05). CORT showed higher concentrations at day 0 compared to days −5 to −2 and +1 to +5 (p < 0.05). ALD showed higher concentrations at day 0 compared to days −5 to −2 (p < 0.05) and +2 (p < 0.05). Na+ and Cl− showed higher concentrations at day 0, compared to day −5 and +5. K+ showed lower concentrations at day 0 compared to day +1 (p < 0.05). The significant correlations obtained between ACTH and CORT (r = 0.20) and between ACTH and ALD (r = 0.32) suggest that although ACTH may have an effect both on CORT and ALD, there are other very important determinants that could be considered. Hence, it is possible to presume that the pituitary adrenocortical response and ALD may be involved in the ovulatory mechanisms without a direct relation with electrolyte pattern.

show abstract

Effect of dietary carbohydrates and time of year on ACTH and cortisol concentrations in adult and aged horses

Cited by 28 publications

References 25 publications

Evaluation of dynamic testing for pituitary pars intermedia dysfunction diagnosis in donkeys

Evaluation of dynamic testing for pituitary pars intermedia dysfunction diagnosis in donkeys

Temporary Relocation during Rest Periods: Relocation Stress and Other Factors Influence Hair Cortisol Concentrations in Horses

Endocrine and Electrolyte Balances during Periovulatory Period in Cycling Mares

Contact Info

Product

Resources

About