Ploceus Philippinus Research Articles

Polymorphic sequence in the ND3 region of Java endemic Ploceidae birds mitochondrial DNA

Susanti R (2011) Polymorphic sequence in the ND3 region of Java endemic Ploceidae birds mitochondrial DNA. Biodiversitas 12: 70- 75. As part of biodiversity, Ploceidae bird family must be kept away from extinction and degradation of gene-diversity. This research was aimed to analyze ND3 gene from mitochondrial DNA of Java Island endemic of Ploceidae bird. Each species of Ploceidae birds family was identified based on their morphological character, then the blood sample was taken from the birds nail vein. DNA was isolated from blood using Dixit method. Fragment of ND3 gene was amplified using PCR method with specific primer pairs and sequenced using dideoxy termination method with ABI automatic sequencer. Multiple alignment of ND3 nucleotide sequences were analyzed using ClustalW of MEGA-3.1 program. Estimation of genetic distance and phylogenetic tree construction were analyzed with Neighbor-Joining method and calculation of distance matrix with Kimura 2 –parameter. The result of Java Island endemic of Ploceidaebird family exploration showed that Erythrura hyperythra and Lonchura ferruginosa can not be found anymore in nature, but the Lonchura malacca that are not actually Java island endemic was also found. Nucleotide sequence of mitochondrial ND3 gene of Ploceidae bird family showed a quite high polymorphism, with 122 substitutions from 334 nucleotides analyzed. Phylogenetic tree of nucleotide sequence of Ploceidae bird family formed 2 clusters. One cluster consisted of the Ploceus hypoxanthus, Ploceus philippinus, Ploceus manyar and Passer montanus, and the others species were included in the second cluster. ND3 gene sequence data from this Ploceidae family need to be analyzed further to see possible relationship with a particular phenotype.

Population ecology of a phthirapteran occurring on the common Baya (Ploceus philippinus) (Ploceidae: Passeriformes: Aves)

One hundred common Bayas (Ploceus philippinus) were examined for their ectoparasites, during April 2006 to December 2008 in the Rampur district of India (28°49'12"N 79°1'11"E). Seventy-four animals were found infested (mean intensity 13.97, sample mean abundance 10.3, range of infestation 1-45) with an ischnoceran louse, Brueelia plocea. The frequency distribution pattern of the louse on the aforesaid bird was aggregated but did not conform to the negative binomial model. The sex ratio was female biased while the nymphal population was dominant over adults.

Nesting behaviour of the Baya Weaver bird, Ploceus philippinus (Ploceidae) and the life-cycle of the Plains Cupid butterfly, Chilades pandava (Lycaenidae) with the red-listed Cycas sphaerica and C. beddomei (Cycadaceae)

The Baya Weaver bird, Ploceus philippinus utilizes the well developed leaves of Cycas sphaerica for nest construction and offspring production. It constructs nest on the leaf tips of this species; the nest material used is exclusively Dendrocalamus strictus. This bird species does not utilize Cycas beddomei for nest construction and offspring production. The Plains Cupid butterfly, Chilades pandava utilizes the newly emerging leaves of both C. sphaerica and C. beddomei for raising its offspring. In both the Cycas species, the new leaves emerge as a crown at the top of the plant; the larvae of C. pandava feed on these leaves and make the plant as leafless until the next leaf flushing season. New leaf production occurs after coning event in Cycas species; coning is not annual event. In consequence, the plants utilized by C. pandava for the production of its offspring remain leafless until the next coning season and their survival during this period depends on the nutrient status within the shoot system and in the soil system. The study suggests that there is no direct or indirect interaction between C. pandava and P. philippinus. C. sphaerica serves as a host plant for these two animal species at different times; but the interaction of these animal species is dependent on the leaves only; C. pandava on newly emerging leaves while P. philippinus on well developed leaves.

Photoperiodism, pineal clock and seasonal reproduction in the Indian Weaver Bird (Ploceus philippinus)

Previous studies show that, in birds, pineal melatonin is important for circadian rhythmicity, and circadian rhythms mediate photoperiodic effects. The effect of pinealectomy or melatonin administration in photoperiodic induction of testicular growth is not found in many bird species. This is inconsistent with the fact that avian pineal is a self-sustained circadian biological clock and decodes both the daily and annual photoperiodic information. Does this mean that the pineal clock in birds regulates circadian rhythms, but not the one that is involved in the photoperiodic induction of the seasonal response? We have examined this in experiments on the subtropical Indian Weaver Bird (Ploceus philippinus). We investigated the effects of the absence of the pineal gland or exogenous melatonin administration on circadian rhythmicity in activity, and on photoperiodic induction of testicular growth, androgen-dependent beak pigmentation and luteinizing hormone-specific plumage coloration. Weaver birds were subjected for several weeks to short day length (8 h light: 16 h darkness, 8L:16D), long day length (16L:8D) and to light–dark cycles that tested the involvement of circadian rhythmicity in photoperiodic time measurement. The results show that circadian pineal clock may regulate the circadian rhythm in activity, but is not essential for the expression of photoperiodism associated with the photoperiodic induction of testicular growth. This suggests that the circadian activity and photosensitivity rhythms are outputs of different circadian oscillators or of the same set of circadian oscillators, but that they are not closely coupled.

Sequential settlement by nesting male and female Baya weaverbirds Ploceus philippinus: the role of monsoon winds

Theory predicts that females should track resources while making decisions about where to reproduce, and males should track females. However, when males create the resource that females require, female settlement follows that of males. In this situation, how do individuals make settling decisions and what are the fitness consequences of these decisions? Here, I test the hypothesis that environmental factors (wind direction and velocity) affect optimal nest placement and orientation, and thus male and female settlement, in Baya weaver Ploceus philippinus colonies. Nests experimentally placed in windward locations with entrance tubes oriented toward the wind were more likely to lose clutches of artificial eggs than were nests placed in other combinations of placement and orientation. Correspondingly, males built their nests strongly clustered on the leeward side of colony trees, with entrance tubes oriented away from the wind. However, females did not discriminate amongst natural nests on the basis of nest placement or orientation. This may be because the effect of wind on the success of natural nests was small and was overwhelmed by other causes of nest loss. I suggest that, in some situations, female preference may remain undetected because the options available to females are constrained by preceding settlement decisions by males. In these cases, it is necessary to manipulate male distribution outside the range of natural variation to gain a better understanding of selective pressures imposed by female preferences.

What Makes a Good Nest? Benefits of Nest Choice to Female Baya Weavers (Ploceus Philippinus)

Abstract The nests of some birds are built exclusively by males and then displayed to females. In such species, one expects females to choose those nests that provide maximum safety to themselves and their offspring. What attributes of a nest should females use in making these choices? Here, I examine the correlates of nesting success in the Baya Weaver (Ploceus philippinus), a species in which males provide nests and little else. In particular, I examine which of two suites of nest attributes best predicts nesting success: nest location (which reflects male competitive ability) or nest architecture (which reflects male building skill). Because whether a nest has successfully fledged young is sometimes uncertain, I supplement generalized linear model analyses with survival analyses, which can incorporate ambiguity in nest fate. Together, these analyses reveal that nests built in thorny trees and woven with fine fiber have high success. Nesting success also increases with nest height and with thickness of the supporting branch. Overall, nest location is a slightly better predictor of success than nest architecture; this is consistent with previous findings that female choice of nests is influenced more by location than by architecture. ¿Qué Hace a un Nido un Buen Nido? Beneficios de la Selección de Nidos para las Hembras en Ploceus philippinus

WHAT MAKES A GOOD NEST? BENEFITS OF NEST CHOICE TO FEMALE BAYA WEAVERS (PLOCEUS PHILIPPINUS)

Abstract The nests of some birds are built exclusively by males and then displayed to females. In such species, one expects females to choose those nests that provide maximum safety to themselves and their offspring. What attributes of a nest should females use in making these choices? Here, I examine the correlates of nesting success in the Baya Weaver (Ploceus philippinus), a species in which males provide nests and little else. In particular, I examine which of two suites of nest attributes best predicts nesting success: nest location (which reflects male competitive ability) or nest architecture (which reflects male building skill). Because whether a nest has successfully fledged young is sometimes uncertain, I supplement generalized linear model analyses with survival analyses, which can incorporate ambiguity in nest fate. Together, these analyses reveal that nests built in thorny trees and woven with fine fiber have high success. Nesting success also increases with nest height and with thickness of ...

Elaborate Nests in a Weaverbird: A Role for Female Choice?

AbstractStudies on sexual selection have focused on behaviour and morphology, but several groups of animals build elaborate structures associated with acquiring a mate. I investigated female choice for nests built by male baya weavers (Ploceus philippinus). Nest choice by females should be strong, as nests are obvious direct benefits provided by males. I used a field experiment supplemented with correlational information to ask whether females appear to base mate choice decisions on male behaviour, nest architecture, and nest location. When the nests of highly visited males were exchanged with those of poorly visited males, female visits remained highest at the original male and location. I found no relationship between female choice and male display or other behaviour. Correlational analyses show that nest location was a better predictor of female choice than was nest architecture. These data suggest that current female choice is driven more by access to safe nesting sites rather than to well‐built nests, possibly because all males are able to build nests of adequate quality. However, nest architecture is unlikely to be irrelevant to females, and its role deserves further investigation.

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

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 sham-operated (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 (LLdim). 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 LLdim, 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.

Selection of nest platforms and the differential use of nest building fibres by the Baya weaver,Ploceus philippinusLinnaeus 1766

The choice by the Baya weaver between different plant species as nesting platforms and sources of nesting fibre was analysed on an agricultural study plot at Chorao (15°30’N, 73°50’E), an island in the Mandovi estuary in Goa, India. The bird chose eucalyptus over coconut palms, as shown by a higher ratio of utilised trees to available trees and by the maintenance of significantly higher numbers of total nests (t = 2.92, P < 0.05) and viable nests (t = 3.10, P < 0.05). The wider anchoring area, providing a better display front for the male birds competing for mates, and the protection against monsoon vagaries (such as rains and winds) provided by the extensive drooping canopy of profuse branches seem to have favoured of eucalyptus trees over coconut palms. The choice went against short and medium sized coconut palms and tall eucalyptus trees, as probably the former were more prone to the menace of intruders and the latter were more exposed to strong monsoon winds. The birds exhibited a differential use of nesting fibres to fabricate the different zones of the nest. Sugarcane fibres, which probably provided better anchorage and stability due to their interlocking silicious spicules, were used for the base, stalk and roof of the brood chamber. Fibres from coconut leaves went into the construction of the entrance tube and floor of the brood chamber, probably to provide added comfort to the altricial young and incubating parent and to afford the required resistance against wear and tear owing to frequent movements of the mother bird while ferrying food to the young. KEY WORDS: Baya weaver, Ploceus philippinus, bird, breeding, nest platforms.

Use of Baya Ploceus philippinus nests in pottery and crop protection in Rajasthan

Use of Baya Ploceus philippinus nests in pottery and crop protection in Rajasthan

Role of melatonin in photoperiodic time measurement in the migratory redheaded bunting (Emberiza bruniceps) and the nonmigratory Indian weaver bird (Ploceus philippinus).

In the present study, we asked the question whether physiological responses to day length of migratory redheaded bunting (Emberiza bruniceps) and nonmigratory Indian weaver bird (Ploceus philippinus) are mediated by the daily rhythm of melatonin. Melatonin was given either by injection at certain times of the day or as an implant. In series I experiments on the redheaded bunting, melatonin was administered by subcutaneous injections daily at zeitgeber time (ZT) 4 (morning) or ZT10 (evening) and by silastic capsules in photosensitive unstimulated buntings that were held in natural day lengths (NDL) at 27 degrees N beginning from mid February, and in artificial day lengths (ADL, 12L:12D and 14L:10D). Melatonin did not affect the photoperiod-induced cycles of gain and loss in body mass and testicular growth-involution, but there was an effect on temporal phasing of the growth-involution cycle of testes in some groups. For example, the rate of testicular growth and development was faster in birds that received melatonin injection at ZT4 in NDL, and was slower in birds that carried melatonin implants both in NDL and ADL. In series II experiments on Indian weaver birds, melatonin was given in silastic capsules in the first week of September when they still had large gonads. Birds were exposed for 12 weeks to short day length (8L:16D; group 1), to long day length (eight weeks of 16L:8D and four weeks of 18L:6D; group 2), or to both short and long day lengths (four weeks each of 8L:16D, 16L:8D, and 18L:6D; groups 3 and 4). Whereas groups 1 to 3 carried melatonin or empty implant from the beginning, group 4 received one after four weeks. All birds underwent testicular regression during the first four weeks irrespective of the photoperiod they were exposed to or the implant they carried in, and there was a slight re-initiation of testis growth in some birds during the next eight weeks of long day lengths. However, with the exception of group 2, there was no difference in mean testis volume during the period of experiment between the melatonin- and empty-implant birds. The data on androgen-dependent beak color also supported the observations on testes. Together, these results do not support the idea that the daily rhythm of melatonin is involved in the photoperiodic time measurement in birds. However, there may still be a role of melatonin in temporal phasing of the annual reproductive cycle in birds.

Testosterone accelerates the onset of photorefractoriness in baya weaver Ploceus philippinus.

The baya weaver Ploceus philippinus, despite its purely tropical origin and tropical/subtropical distribution, exhibits all features of a typically photoperiodic species. The onset of reproduction in this species is triggered by increasing daylength and breeding is terminated by the development of distinct photorefractory phase. In order to ascertain the involvement of androgens in the development of photorefractoriness the long day response of birds was tested after a prior exposure to varied doses of testosterone. Testosterone treatment accelerated the onset of photorefractoriness as judged from the gonadal status, LH-dependent yellow plumage and testosterone-dependent beak pigmentation. While gonadal development and yellow plumage occurred in the control birds due to the stimulatory long photoperiod, the testosterone administered birds failed to show such developments. These findings indicate that testosterone might impair the higher photoresponding mechanisms resulting in the development of photorefractoriness.

Exogenous melatonin may act as a reproductive‐phase dependent modulator of the relationship in morphology between pineal and adrenal cortex in male blossomheaded parakeet(Psittacula cyanocephala)and Indian Weaver bird (Ploceus philippinus)

Abstract The influence of melatonin, at a daily dose of 250 μg/100 g b.w. for ten consecutive days on morphological parameters of the pineal and adrenal cortex was investigated in two diverse avian species, Blossomheaded parakeet (Psittacula cyanocephala) and Indian Weaver bird (Ploceus philippinus). The results suggest that melatonin administered during the breeding phase caused stimulation of the adrenal cortex as evidenced from the significant increase in adrenocortical cord width and nuclear size in both avian species. However, the pineal gland in both species remained unaltered during this phase. On the contrary, melatonin given during the non‐breeding phase failed to alter the adrenal cortex but stimulated the pineal gland activity as evidenced from the significant increase in pinealocyte nuclear diameter in both species alike. It is suggested that melatonin can act as a reproductive‐phase dependent modulator of the pineal gland and adrenal cortex in these birds.

Photoperiodic Regulation of Follicle-Stimulating Hormone Binding to Gonads and of Plasma Gonadotropin Concentrations in Indian Weaver Birds

Previous studies showed that changes of gonadal weight and of follicle-stimulating hormone (FSH) receptor number in response to fluctuations in natural environmental conditions are smaller in female than in male Indian weaver bird ( Ploceus philippinus). Therefore, we studied whether the response to artificial photoperiodic changes differs between the sexes. Birds were transferred to short-day (SD) photoperiods during the breeding phase (June). Other birds were subjected to long-day (LD) photoperiods during the nonbreeding phase (December). Exposure to SD for 10 weeks induced a marked testicular weight decrease. Similarly, FSH binding per unit testicular weight as well as per two testes decreased after SD exposure. The influence of photoperiodic manipulations on the ovarian weight was much smaller than that on the testicular weight. SD exposure did not alter FSH binding either per unit ovarian weight or per ovary. Plasma gonadotropin concentration significantly decreased in both sexes subjected to SD environment. On the other hand, exposure to LD significantly increased testicular weight. LD exposure slightly increased ovarian weight, but the increase was statistically not significant. FSH binding per unit testicular weight markedly increased 10 weeks after transfer to LD. The total FSH binding per two testes showed a parallel change with the testicular weight. However, there was no significant increase in FSH binding per unit ovarian weight during 10 weeks of LD exposure. Although LD exposure for 10 weeks significantly increased the total FSH binding per ovary, the rate of increase was much smaller than that in the testes. The plasma gonadotropin level in both sexes was increased by LD exposure. Scatchard plot analyses of FSH binding indicated that FSH binding changes were due to changes in binding site number. These results suggest that photoperiod regulates FSH receptor numbers particularly in the testis. Such an effect is manifested by marked changes in the testicular weight under different photoperiodic conditions in the subtropical bird.

A Comparative Study of Annual Changes in the Pineal Gland Morphology with Reference to the Influence of Melatonin on Testicular Activity in Tropical Birds, Psittacula cyanocephala and Ploceus philippinus

The aim of the present comparative investigation was to examine annual pineal cytological changes and the action of melatonin in relation to testicular activity in two wild tropical avian species. The findings revealed that in both blossomheaded parakeets (Psittacula cyanocephala) and Indian weaver birds (Ploceus philippinus) the pineal gland was inactive, with reduced karyometric values during the breeding season. A pinealoactive phase showing significantly increased pinealocyte nuclear diameter corresponded with the nonbreeding phase. Administration of melatonin (250 μg/100 g body wt) for 10 consecutive days caused significant involution of testes during the breeding phase, although it failed to alter reproductive activity during the nonbreeding phase. The results indicated that the pineal gland activity varied inversely with the seasonal testicular weight cycle and the antigonadal influence of melatonin appeared to be phase dependent, which corroborated the inverse temporal relationship of the pineal gland and male reproductive activity examined in the two tropical avian species.

Short-day experience is not a prerequisite for the termination of photorefractoriness in the reproductive cycle of baya weaver,Ploceus philippinus

In most photoperiodic avian forms (irrespective of temperate or tropical distribution) including the baya weaver,Ploceus philippinus, seasonal reproduction comes to an end due to the development of a photoperiodically controlled photorefractory phase when birds cease to respond to the stimulatory effect of long days. In the present paper photoperiodic control of the termination of photorefractory phase has been examined by studying the effect of short-day exposure lasting 4–6 months on long-day response of birds. Results indicate that unlike in other photoperiodic birds short-day exposure of winter is not a prerequisite for the termination of photorefractory phase in the reproductive cycle of baya weaver. Artificial long days on the other hand hasten the termination of this phase. Refractory phase in baya weaver, therefore, unlike that in temperate forms, is a temporary state resulting most likely from a sequel of physiological events triggered by long days of spring/summer which temporarily mask the photostimulatory response. Spontaneous termination of photorefractoriness in birds of tropical habitats may have a selective value imparting to the reproductive cycle the necessary elasticity for adaptation to diverse ecological conditions.

Environmental and hormonal interactions in the regulation of seasonal breeding in free‐living male Indian baya weaver birds (Ploceus philippinus)

Environmental and hormonal interactions in the regulation of seasonal breeding in free‐living male Indian baya weaver birds (<i>Ploceus philippinus</i>)

The mechanism of action of epinephrine on the testis of weaver bird Ploceus philippinus.

The present study confirms the extreme degenerative effects of epinephrine on the testis of weaver bird (Ploceus philippinus). Further, the recovery of testicular activities following conjoint administration of Duvadilan proves the vasoconstrictor action of the sympathomimetic amine. Similar testicular response was obtained after application of FSH-gonadotrophin with epinephrine.

Hematological changes produced by lindane (γ-HCH) in six species of birds

Hematological changes were studied after oral administration of lindane (γ-hexachlorocyclohexane) at 5 mg/kg body weight twice in 1 week in 6 species of agriculturally important birds: house sparrow, baya weaver bird, common myna, rose-ringed parakeet, blue rock pigeon and domestic duck. Lindane induced anemia in the birds as judged by reduced RBC count, hematocrit and hemoglobin content with corresponding changes in MCV, MCH and MCHC. Bleeding and clotting time were markedly prolonged. Splenic cell counts were decreased with marginal increase of splenic weight in most of the lindane fed birds. Total leucocyte counts were increased while the differential counts of WBC show marked heterophilia and eosinophilia with a decrease in monocyte, lymphocyte and basophil numbers. Domestic duck appears to be somewhat resistant compared to the wild birds studied. Besides anemia the results suggest both immunosuppression and stress effects and indicate that early hematological changes induced by lindane may serve as an initial warning for pesticide toxicity.