Limits...
Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758).

Ferreira JC, Fujihara CJ, Fruhvald E, Trevisol E, Destro FC, Teixeira CR, Pantoja JC, Schmidt EM, Palme R - PLoS ONE (2015)

Bottom Line: A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment).Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations).This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, Unesp - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, Brazil.

ABSTRACT
Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots' physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3-9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management.

Show MeSH

Related in: MedlinePlus

Boxplots (description see Fig 1) of concentrations of glucocorticoid metabolites (GCM; ng/g droppings) of female Blue-fronted parrots (Amazona aestiva), kept under natural light variation (sunrise: 06:02 ± 0:11 a.m.—sunset: 06:09 ± 0:03 p.m.–mean ± standard deviation), after an injection of saline solution (0.9% NaCl; white boxes), dexamethasone (1 mg/Kg; white striped boxes) and adrenocorticotropic hormone (25 IU of ACTH; gray striped boxes).The control group was kept in the same room but remained undisturbed (gray boxes). Please note the different y-axis scale in the upper (Dexamethasone; ACTH) and lower (Saline; Control) panels. Asterisks beside the gray striped boxes indicate significant differences compared with the same interval of the control group (P < 0.01). The P values of time (T), treatments (Treat) and the interaction time*treatments (T*Treat) are shown.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4696673&req=5

pone.0145909.g002: Boxplots (description see Fig 1) of concentrations of glucocorticoid metabolites (GCM; ng/g droppings) of female Blue-fronted parrots (Amazona aestiva), kept under natural light variation (sunrise: 06:02 ± 0:11 a.m.—sunset: 06:09 ± 0:03 p.m.–mean ± standard deviation), after an injection of saline solution (0.9% NaCl; white boxes), dexamethasone (1 mg/Kg; white striped boxes) and adrenocorticotropic hormone (25 IU of ACTH; gray striped boxes).The control group was kept in the same room but remained undisturbed (gray boxes). Please note the different y-axis scale in the upper (Dexamethasone; ACTH) and lower (Saline; Control) panels. Asterisks beside the gray striped boxes indicate significant differences compared with the same interval of the control group (P < 0.01). The P values of time (T), treatments (Treat) and the interaction time*treatments (T*Treat) are shown.

Mentions: As observed in experiment 1, GCM concentrations also showed a marked time effect (P < 0.001) in the undisturbed control treatment in females. Droppings voided between 5 to 8 p.m. (9 to 12 h interval–Fig 2) had the lowest GCM concentration of the day. Afterwards concentrations started to increase and returned to initial values. In males, no time effect was detected in the control treatment (P > 0.05; Fig 3). Following the saline injection, GCM concentrations in females and males were similar to those observed in the control treatment (P > 0.5). Dexamethasone administration led to a transient increase in GCM in males, between 0 to 3 h after treatment (P = 0.004), followed by a return to pre-treatment concentrations after 3 h (Fig 3). This effect was not observed in female birds. When comparing the baseline concentrations derived from control and saline treatments, no significant effect was observed after dexamethasone administration.


Non-Invasive Measurement of Adrenocortical Activity in Blue-Fronted Parrots (Amazona aestiva, Linnaeus, 1758).

Ferreira JC, Fujihara CJ, Fruhvald E, Trevisol E, Destro FC, Teixeira CR, Pantoja JC, Schmidt EM, Palme R - PLoS ONE (2015)

Boxplots (description see Fig 1) of concentrations of glucocorticoid metabolites (GCM; ng/g droppings) of female Blue-fronted parrots (Amazona aestiva), kept under natural light variation (sunrise: 06:02 ± 0:11 a.m.—sunset: 06:09 ± 0:03 p.m.–mean ± standard deviation), after an injection of saline solution (0.9% NaCl; white boxes), dexamethasone (1 mg/Kg; white striped boxes) and adrenocorticotropic hormone (25 IU of ACTH; gray striped boxes).The control group was kept in the same room but remained undisturbed (gray boxes). Please note the different y-axis scale in the upper (Dexamethasone; ACTH) and lower (Saline; Control) panels. Asterisks beside the gray striped boxes indicate significant differences compared with the same interval of the control group (P < 0.01). The P values of time (T), treatments (Treat) and the interaction time*treatments (T*Treat) are shown.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4696673&req=5

pone.0145909.g002: Boxplots (description see Fig 1) of concentrations of glucocorticoid metabolites (GCM; ng/g droppings) of female Blue-fronted parrots (Amazona aestiva), kept under natural light variation (sunrise: 06:02 ± 0:11 a.m.—sunset: 06:09 ± 0:03 p.m.–mean ± standard deviation), after an injection of saline solution (0.9% NaCl; white boxes), dexamethasone (1 mg/Kg; white striped boxes) and adrenocorticotropic hormone (25 IU of ACTH; gray striped boxes).The control group was kept in the same room but remained undisturbed (gray boxes). Please note the different y-axis scale in the upper (Dexamethasone; ACTH) and lower (Saline; Control) panels. Asterisks beside the gray striped boxes indicate significant differences compared with the same interval of the control group (P < 0.01). The P values of time (T), treatments (Treat) and the interaction time*treatments (T*Treat) are shown.
Mentions: As observed in experiment 1, GCM concentrations also showed a marked time effect (P < 0.001) in the undisturbed control treatment in females. Droppings voided between 5 to 8 p.m. (9 to 12 h interval–Fig 2) had the lowest GCM concentration of the day. Afterwards concentrations started to increase and returned to initial values. In males, no time effect was detected in the control treatment (P > 0.05; Fig 3). Following the saline injection, GCM concentrations in females and males were similar to those observed in the control treatment (P > 0.5). Dexamethasone administration led to a transient increase in GCM in males, between 0 to 3 h after treatment (P = 0.004), followed by a return to pre-treatment concentrations after 3 h (Fig 3). This effect was not observed in female birds. When comparing the baseline concentrations derived from control and saline treatments, no significant effect was observed after dexamethasone administration.

Bottom Line: A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment).Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations).This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management.

View Article: PubMed Central - PubMed

Affiliation: Department of Animal Reproduction and Veterinary Radiology, School of Veterinary Medicine and Animal Science, Unesp - Univ Estadual Paulista, Rubião Junior s/n, 18.618-970, Botucatu, Brazil.

ABSTRACT
Parrots kept in zoos and private households often develop psychological and behavioural disorders. Despite knowing that such disorders have a multifactorial aetiology and that chronic stress is involved, little is known about their development mainly due to a poor understanding of the parrots' physiology and the lack of validated methods to measure stress in these species. In birds, blood corticosterone concentrations provide information about adrenocortical activity. However, blood sampling techniques are difficult, highly invasive and inappropriate to investigate stressful situations and welfare conditions. Thus, a non-invasive method to measure steroid hormones is critically needed. Aiming to perform a physiological validation of a cortisone enzyme immunoassay (EIA) to measure glucocorticoid metabolites (GCM) in droppings of 24 Blue-fronted parrots (Amazona aestiva), two experiments were designed. During the experiments all droppings were collected at 3-h intervals. Initially, birds were sampled for 24 h (experiment 1) and one week later assigned to four different treatments (experiment 2): Control (undisturbed), Saline (0.2 mL of 0.9% NaCl IM), Dexamethasone (1 mg/kg IM) and Adrenocorticotropic hormone (ACTH; 25 IU IM). Treatments (always one week apart) were applied to all animals in a cross-over study design. A daily rhythm pattern in GCM excretion was detected but there were no sex differences (first experiment). Saline and dexamethasone treatments had no effect on GCM (not different from control concentrations). Following ACTH injection, GCM concentration increased about 13.1-fold (median) at the peak (after 3-9 h), and then dropped to pre-treatment concentrations. By a successful physiological validation, we demonstrated the suitability of the cortisone EIA to non-invasively monitor increased adrenocortical activity, and thus, stress in the Blue-fronted parrot. This method opens up new perspectives for investigating the connection between behavioural disorders and stress in this bird species, and could also help in their captive management.

Show MeSH
Related in: MedlinePlus