Plumage Control in Indian Weaver Bird (Ploceus philippinus)

Thapliyal, J. P.; Saxena, R. N.

doi:10.1007/bf00590633

Cited by 24 publications

(11 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Birds darkened and lightened their beak as they grew and regress their testes, respectively (Fig. 1a-h), which confirms a previous finding of Thapliyal and Saxena (1961). Also, there were increased numbers of bright yellow feathers over the head and breast regions in birds that were stimulated under long days, reflecting activity of the hypothalamo-hypophyseal axis (Fig.…”

Section: Discussionsupporting

confidence: 86%

“…In males, beak color changes over seasons from nonbreeding straw to breeding dark black, and feather color over the head and breast regions from nonbreeding ''female-like'' to breeding (nuptial) bright yellow. Therefore, we recorded changes in the beak and feather colors over the head and in the breast regions, using subjective criterion, and considered them an indicator of endogenous androgen (Saxena and Thapliyal 1962) and LH (Thapliyal and Saxena 1961) levels. For better illustration of the observations and statistical comparisons, the beak pigmentation and plumage colors were scored, as described by Trivedi (2004).…”

Section: Methodsmentioning

confidence: 99%

“…Saxena (1964) divided annual testicular cycle of these birds into four (preparatory (quiescent), progressive, breeding and regressive) phases. During breeding season, males develop luteinizing hormone (LH)-specific bright yellow plumage (Thapliyal and Saxena 1961) and a dark pigmented beak, which is indicative of the androgen level (Saxena and Thapliyal 1962). During nonbreeding (quiescent) phase, males have female-like plumage and non-pigmented beak (Thapliyal and Saxena 1961;Saxena and Thapliyal 1962).…”

Section: Introductionmentioning

confidence: 99%

“…During breeding season, males develop luteinizing hormone (LH)-specific bright yellow plumage (Thapliyal and Saxena 1961) and a dark pigmented beak, which is indicative of the androgen level (Saxena and Thapliyal 1962). During nonbreeding (quiescent) phase, males have female-like plumage and non-pigmented beak (Thapliyal and Saxena 1961;Saxena and Thapliyal 1962). Previous studies have shown that, (1) it is a photoperiodic species (Thapliyal and Tewary 1964), (2) circadian photosensitivity rhythm mediates photoperiodic induction (Chandola et al 1976) and (3) pinealectomy accelerates photoperiodic induction under long days, and appears to change the perception of short days (Balasubramanian and Saxena 1973).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

The pineal clock affects behavioral circadian rhythms but not photoperiodic induction in the Indian weaver bird (Ploceus philippinus)

2005

View full text Add to dashboard Cite

We investigated whether pineal is part of the circadian clock system which regulates circadian rhythms of activity and photosensitivity in the Indian weaver bird (Ploceus philippinus). Two experiments were performed. The first experiment examined the induction of testicular growth, and androgen-dependent beak pigmentation and luteinizing hormone (LH)-specific plumage coloration in pinealectomised (pinx) and shamoperated (sham) birds exposed to short day (8 h light: 16 h darkness, 8L:16D) and long day (16L:8D) for 9 months in the late breeding and early regressive phase (October), or the late regressive and preparatory phase (January) of the annual testicular cycle. As expected, short days were non-stimulatory, and long days stimulated testicular growth, beak pigmentation and plumage coloration. There was no difference in the response between pinx and sham birds subjected to short or long days in October, but the response was enhanced in pinx birds that were subjected to long day in January. In the second experiment circadian behavioral rhythms were studied (activity pattern in singly housed birds) in weaver birds first exposed at two different phases of the annual testicular cycle to a stimulatory photoperiod (12L:12D in preparatory phase or 13L:11D in early breeding phase) and then released into dim continuous light (LL dim ). All birds showed synchronization to the light period before and after the pinealectomy; there was no difference in the response between pinx and sham birds. When released into LL dim , sham birds exhibited circadian rhythmicity continuously, whereas pinx birds lost circadian rhythmicity after some cycles. Considered together, these results suggest that circadian clock residing within the pineal gland regulates the circadian rhythm in activity, but not the circadian rhythm involved in photoperiodic induction of the Indian weaver bird.

show abstract

Section: Discussionsupporting

confidence: 86%

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The pineal clock affects behavioral circadian rhythms but not photoperiodic induction in the Indian weaver bird (Ploceus philippinus)

2005

View full text Add to dashboard Cite

show abstract

“…As in human skin cytosol (Mowszowicz et al 1981), androgen receptors have been reported in the uropygial glands of male ducks (Daniel et al 1977) which would be quite typical of an androgen target site. Interestingly, an extragonadal direct effect of luteinizing hormone (LH) on the seasonal plumage changes has been proposed in the orange weaver finch Euplectes franciscanus (Witchi 1950) and Indian weaver bird Ploceus philippinus (L) Tewary 1961, 1963 ;Thapliyal and Saxena 1961). It would be noteworthy to find out the advantage of gonadotrophic control over gonadal steroids in the formation of nuptial plumage in the weaver birds.…”

Section: Introductionmentioning

confidence: 99%

Steroid metabolism in target related to nuptial plumage production in the Baya weaver bird

Kotak

Menon

1982

Proc Ani Sci

View full text Add to dashboard Cite

To elucidate the possible utilization of gonadal sex hormones by the nuptial plumage producing skin, histochemical localization of 3P-, 3a-and 17P-hydroxysteroid dehydrogenases was carried out in the skin from crown region (characterized by bright yellow plumage) and ventrum, and testes of the Baya weaver bird Ploceus philippinus (L) during the breeding phase. Results indicate higher activity of 17P-hydroxysteroid dehydrogenase in the crown skin, when testosterone was used as substrate. Possibly, skin from the crown region actively metabolizes androgens and this in turn is correlated to the production of nuptial plumage.

show abstract