Using a GnRH agonist to obtain an index of testosterone secretory capacity in the cockatiel (<i>Nymphicus hollandicus</i>) and sulphur‐crested cockatoo (<i>Cacatua galerita)</i>

Lovas, EM; Johnston, S. D.; Filippich, L. J.

doi:10.1111/j.1751-0813.2009.00533.x

Cited by 16 publications

(5 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recovery tests were performed by combining equal volumes of diluted urofecal extract and known amounts of exogenous hormone and calculating the difference between the expected and observed concentrations of exogenous hormone (androgens: y = 1.06x + 1.59, R 2 = 0.99; and progestagens: y = 0.80 x À 4.24, R 2 = 0.98;). To assess the physiological relevance of immunoreactive urofecal androgen metabolites, we challenged two adult Blue-fronted males with buserelin acetate (Conceptal, Intervet, Cotia, Brazil) at a dosage of 8 mg/kg (Lovas et al, 2010). This resulted in a three-fold increase in androgen levels within 4-8 hs following administration.…”

Section: Steroid Extraction and Analysismentioning

confidence: 99%

“…These numbers emphasize the importance of captive breeding to promote either sustainability of global trade of parrots or their conservation. However, large-scale production of psittacines to satisfy pet market demand is restricted to a few species (mostly budgerigars, cockatiels, lovebirds and small conures; Engebretson, 2006), and even for them very little information exists on reproductive endocrinology (Myers et al, 1989;Lee et al, 1999;Costantini et al, 2009;Lovas et al, 2010;Hahn et al, 2011). This lack of endocrinological data for Neotropical parrots hinders future research involving manipulation of reproductive cycles (through artificial lighting or hormone treatments) or adjustments to existing biotechnologies (e.g., artificial insemination).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Urofecal steroid profiles of captive Blue-fronted parrots (Amazona aestiva) with different reproductive outcomes

Pereira

Christofoletti

Blank

et al. 2018

General and Comparative Endocrinology

View full text Add to dashboard Cite

Despite Psitaciformes (parrots) being the third largest nonpasserine order (398 species), it currently ranks second in number of threatened species (28%) according to the Internatinal Union for Conservation of Nature (IUCN) criteria. Since most of the literature concerning reproductive endocrinology in avian species derives from domestic and song birds, it is puzzling that advances in reproductive science for the Psitaciformes order lags far behind, in spite of the growing threats against them. In order to expand our knowledge of Neotropical parrots (Psittacidae), we examined annual changes in urofecal sex steroid metabolites of Blue-fronted amazon pairs (Amazona aestiva) exhibiting successful (nestlings) and unsuccessful breeding (infertile or no eggs). Urofecal samples were collected over a year from eight breeding pairs housed under the same environmental and management conditions. Fecal androgen and progestagen concentrations were determined in males and females, respectively, by enzyme immunoassays previously validated for this species. All eggs were registered between late winter and mid-spring, and egg-laying intervals varied between females (range: 1-8 days; average 3.60 ± 0.51 days). Similar profiles of urofecal progestagens were observed in reproductively successful females and females producing infertile eggs, with progestagen peaks preceding egg laying events (1.77 ± 0.50 days). In contrast, non-laying females had no rises in progestagens during the year. Successful and unsuccessful males did not displayed distinct annual patterns of androgen production, and apart from the peaks during the breeding season, more than half of the individuals intriguingly presented significant increases from late summer to early autumn, a period without reproductive activity. Finally, we noticed that samples with progestagen levels exceeding 40 ng/g had very high probability (>97.5%) to be from females in pre-laying or laying phases, suggesting a feasible application of this characteristic to noninvasively discriminate the reproductive status in amazon females with an accuracy and sensitivity of 94.55% and 58.13%, respectively. Our findings confirmed that urofecal progestagens and androgens are good indicators of the gonadal condition in Blue-fronted amazons, but there is still much to be done for their extensive use in artificial insemination or selection of the most suitable breeding birds for the season.

show abstract

Section: Steroid Extraction and Analysismentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Urofecal steroid profiles of captive Blue-fronted parrots (Amazona aestiva) with different reproductive outcomes

Pereira

Christofoletti

Blank

et al. 2018

General and Comparative Endocrinology

View full text Add to dashboard Cite

show abstract

“…0,26 ng/ml (Halsbandsittiche). Im Vergleich zu den in der Literatur angegebenen Testosteronkonzentrationen für Nymphensittiche (29), Amazonen (32) und Halsbandsittiche (26, 31) sind die in dieser Studie ermittelten Testosteronwerte deutlich geringer. Das kann einerseits mit den Unterschieden in den Methoden der Hormonanalytik, andererseits mit den Haltungs-und Umweltbedingungen erklärt werden.…”

Section: Diskussionunclassified

Endokrinologische Untersuchung männlicher Papageienvögel zur Beurteilung ihres Reproduktionsstatus

Hahn¹,

Reitemeier²,

Gottschalk³

et al. 2011

Tierarztl Prax Ausg K

View full text Add to dashboard Cite

Zusammenfassung Gegenstand und Ziel: Etablierung von Methoden zur Hormonbestimmung in verschiedenen Medien bei männlichen Papageienvögeln mit dem Ziel, deren Reproduktionsstatus und Stressachse zu ermitteln. Material und Methoden: Als Vertreter der Papageienartigen (Psittaciformes) wurden Nymphen- und Halsbandsittiche endokrinologisch untersucht. Vorversuche dienten der Etablierung geeigneter Methoden zur Bestimmung von Testosteron in Plasma, Speichel und Kot. Zur Extraktion der Blut- und Kotproben erwies sich Diethylether als Mittel der Wahl, während der Speichel direkt ohne Extraktion in den Testosteron-Enzymimmunoassay eingesetzt werden konnte. Da Papageien hauptsächlich konjugierte Testosteronmetaboliten im Kot ausscheiden, wurden die Kotproben vor der Etherextraktion mithilfe der β-Glucuronidase/Arylsulfatase hydrolysiert. Neben Testosteron wurde das Stresshormon Kortikosteron im Blut untersucht. Die Kortikosteronanalyse erfolgte durch Fällung der Proteine mittels absolutem Alkohol und Einsatz der Plasmaextrakte im Radioimmunoassay. Ergebnisse: Die untersuchten Papageienspezies zeigten sowohl für Testosteron als auch für Kortikosteron unterschiedliche jahreszeitlich bedingte Sekretionsmuster. Die Nymphensittiche erreichten im Februar und die Halsbandsittiche im November maximale Testosteronspiegel im Blut. Bedingt durch die kumulative Ausscheidung lagen die Testosteronkonzentrationen im Kot wesentlich höher als im Blut. Bezüglich der Stresshormonspiegel wiesen die Halsbandsittiche insgesamt deutlich höhere Werte auf als die Nymphensittiche. Schlussfolgerung: Durch diese Studie ließen sich geeignete Methoden zur Testosteronanalyse in Blut und Kot beim Nymphen- und Halsbandsittich etablieren, mit deren Hilfe eine Einordnung ihres Reproduktionsstatus möglich ist. Die Hormonanalyse im Speichel stellt zum jetzigen Zeitpunkt keine zuverlässige Methode dar und bedarf weiterer Untersuchungen. Klinische Relevanz: Durch Verlaufsuntersuchungen können ein Anstieg der Testosteronkonzentration und/oder pathologische Veränderungen ermittelt und bei der Zuchtplanung berücksichtigt werden.

show abstract

“…This study reports the validation of a stimulation test using a synthetic gonadotrophin releasing hormone agonist (GnRHa), buserelin, for determining the steroidogenic capacity of the testis of cockatiels and cockatoos 9 . Baseline blood sampling followed by buserelin injection and blood sampling 60 to 90 min later gave a reliable index of testosterone secretion in the cockatiels.…”

Section: Avianmentioning

confidence: 99%

In this issue – January/February 2010

Jackson

2010

Aust Veterinary J

View full text Add to dashboard Cite

show abstract

Using a GnRH agonist to obtain an index of testosterone secretory capacity in the cockatiel (Nymphicus hollandicus) and sulphur‐crested cockatoo (Cacatua galerita)

Abstract: Buserelin can be used to obtain a reliable index of the prevailing testosterone capacity of the cockatiel and cockatoo testis. With further studies, this test may be incorporated into clinical assessment of reproductive status.

Cited by 16 publications

References 13 publications

Urofecal steroid profiles of captive Blue-fronted parrots (Amazona aestiva) with different reproductive outcomes

Urofecal steroid profiles of captive Blue-fronted parrots (Amazona aestiva) with different reproductive outcomes

Endokrinologische Untersuchung männlicher Papageienvögel zur Beurteilung ihres Reproduktionsstatus

In this issue – January/February 2010

Contact Info

Product

Resources

About