Female Budgerigars Research Articles

Cere Colour as a Basis for Extra‐pair Preferences of Paired Male Budgerigars (Melopsittacus undulatus: Psittacidae: Aves)

AbstractMale budgerigars may be limited in the time they have available to pursue extra‐pair copulations because of conflicts with other reproductive behaviour. If males could selectively court only immediately fertilizable extra‐pair females they should do so. The cere colour of a female budgerigar may be used as a cue to her reproductive readiness. We experimentally tested the hypothesis that males prefer females with dark ceres, which are indicative of developed ovaries, over females with light‐coloured ceres, characteristic of birds with undeveloped ovaries. In a pairwise choice experiment between females that had their cere colour artificially manipulated, pair‐bonded males were more likely to choose the female with the dark‐coloured cere.

Mate choice and reproductive success in the domesticated budgerigar,Melopsittacus undulatus

Abstract Female budgerigars that had been given the opportunity to choose their mate laid more promptly, produced a higher number of eggs and reared a higher number of fledgings than females that had been denied the possibility to choose a mate and had been paired at ran dom. In addition, males of self‐selected pairs performed courtship singing at higher rate than those of random pairs. However, in the following brood most differences disappeared as the number of eggs laid and young fledged increased in the random group and the rate of courtship singing decreased in the self‐selected group. It appears, therefore, that choosy females do enjoy a reproductive advantage even though they do not necessarily choose genetically superior males. Male budgerigars singing too little might be simply unable to stimulate ovarian development and sexual response of the female.

Leiomyosarcoma in a Budgerigar (Melopsittacus undulatus)

A tumor mass defined as a leiomyosarcoma was found in the thoracic cavity of a 3-year-old female budgerigar. Disseminated leiomyosarcomas were found in various body tissues, including bone marrow, spleen, and liver.

Adenocarcinoma of the kidney in two budgerigars

Two female budgerigars with kidney tumours are described. They both had a history of gradual emaciation. One bird also had abdominal distention and a paralysed left leg. Histologically, the tumours appeared to be adenocarcinomas. The occurrence and histological appearance of kidney tumours in budgerigars are compared to findings of other authors.

Temporal relationships between nesting behaviour, ovary and oviduct development during the reproductive cycles of female budgerigars.

The development of nesting behaviour in female budgerigars was observed from nestbox entry until three days after the last egg was laid and correlated with the development of the ovary, oviduct and brood patch. Female budgerigars entered nestboxes eight to nine days (median: 9; range: 8-22) before laying the first egg. Behaviour patterns performed in the nestbox included walking about, looking out of the entrance hole, preening, gnawing the floor and sitting or standing in the nest hollow. After the first egg was laid the females spent 98%-100% of the observation period in the incubation posture sitting in the nest hollow. Males paired with these females began to enter the nestboxes intermittently six days before the first egg was laid. Males entered the nestboxes for short durations throughout the reproductive cycle and did not participate in nesting behaviour. The gnawing behaviour of females provided with hard and soft nesting substrates was compared. The durations of gnawing were approximately four times longer for females with the soft nesting substrate. But there was no difference between the groups in latency to egg-laying, suggesting that gnawing does not play a regulatory role in nesting behaviour. No changes in the brood patch area occurred in females on the first day of nest entry. Defeathering of the abdominal region was first evident six days before the first egg was laid and coincided with the onset of intensive nesting behaviour. Further increases in the rate of defeathering and vascularity of the abdominal-thorax and crop regions commenced one to two days before the first egg was laid. Maximum brood patch development occurred after the second egg was laid. The oviducts were small with tubular glands being formed in the magnum region in females on the first and second days of nestbox entry. But, three to four days after entering the nest-boxes, females which showed a daily increase in duration in the nestboxes also showed an increase in oviduct weight with albumen formed in the tubular glands of the magnum region. The temporal relationships between oviduct and ovarian development and nesting behaviour were similar to those of nest-building species such as the canary. Brood patch development was temporally related to incubation behaviour and egg-laying. It can be suggested that the integration of temporal patterning of nesting behaviour and somatic development in a non-nest building species such as budgerigars depends on relatively similar hormonal factors and environmental stimuli to those species which construct a nest.

Effect of male vocalizations on the nest-occupation response of female budgerigars to oestrogen and prolactin.

Effect of male vocalizations on the nest-occupation response of female budgerigars to oestrogen and prolactin.

Changes in the sensitivity of female budgerigars to male vocalizations

Journal of ZoologyVolume 179, Issue 3 p. 407-410 Changes in the sensitivity of female budgerigars to male vocalizations Susan Gosney, Susan Gosney MRC Unit on the Development and Integration of Behaviour, Sub-Department of Animal Behaviour, Madingley, CambridgeSearch for more papers by this authorR. A. Hinde, R. A. Hinde MRC Unit on the Development and Integration of Behaviour, Sub-Department of Animal Behaviour, Madingley, CambridgeSearch for more papers by this author Susan Gosney, Susan Gosney MRC Unit on the Development and Integration of Behaviour, Sub-Department of Animal Behaviour, Madingley, CambridgeSearch for more papers by this authorR. A. Hinde, R. A. Hinde MRC Unit on the Development and Integration of Behaviour, Sub-Department of Animal Behaviour, Madingley, CambridgeSearch for more papers by this author First published: July 1976 https://doi.org/10.1111/j.1469-7998.1976.tb02303.xCitations: 12AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume179, Issue3July 1976Pages 407-410 RelatedInformation

EFFECTS OF OVARIAN STEROIDS AND PROLACTIN ON THE SEQUENTIAL DEVELOPMENT OF NESTING BEHAVIOUR IN FEMALE BUDGERIGARS

As intact, breeding female budgerigars approach egg-laying, they spend an increasing amount of time in the nestbox and nest hollow. The brood patch area begins to defeather and becomes vascular and the oviduct increases in weight. Precursory albumen forms in the tubular glands of the oviduct. Oestradiol (OB) treatment in combination with prolactin (OB+PL) induced ovariectomized budgerigars to display nesting behaviour which did not differ from that shown by intact females in the 3 days immediately preceding egg-laying. In contrast, OB induced only the initial phase of the nesting sequence and the effects of OB in combination with progesterone (OB+PR) were intermediate between treatments with OB alone and OB+PL. Incubation of artificial eggs occurred only in the OB+PL group and the latency to display of the incubation posture was shorter in the OB+PL group than in the OB+PR group. No incubation posture was displayed by the OB-treated group. Oviduct development was not influenced by prolactin, but progesterone induced precocious development of tubular glands in the magnum region of the oviduct. Treatment with OB+PR induced uniform development of precursor albumen in the tubular glands. Development of the brood patch occurred with both OB+PL and OB+PR treatment. However, OB+PR resulted in defeathering which was advanced in relation to vascularity when compared with intact breeding females, whereas defeathering and vascularity of the OB+PL group did not differ from that of intact females at egg-laying. These results indicate that prolactin in combination with oestradiol was more effective than progesterone not only in inducing the later phases of nesting behaviour but also in initiating incubation behaviour and defeathering of the brood patch area.

Photoperiodic control of budgerigar reproduction: circadian changes in sensitivity

Female budgerigars provided with nest boxes and exposed to male vocalizations were kept on light regimes involving 6 h of light and then a further 2 h of light starting 8, 12, 16, 17 or 18 h after the initial dawn. A higher proportion of females laid when the second light period started 6 h after the first one, than when it started earlier or later. That the effect was not due merely to the males vocalizing more on this light regime than on others was shown by substituting for the males taped vocalizations played during the light periods. It remains possible that females are more responsive to those vocalizations instead of/as well as to light at some points of the circadian cycle than others.

Temporal patterning of external stimuli and reproductive behaviour in female budgerigars

The role of stimuli from the nestbox, the male and breeding females in regulating the course of reproductive development in female budgerigars is examined. When females were paired with males but deprived of nestboxes no development of the overy, oviduct or brood patch occurred. Females visually and auditorily isolated from males entered their nestboxes, but fewer (8 per cent) laid eggs than females paired with males (75 per cent). More females (50 per cent) hearing only breeding females laid eggs than females (8 per cent) isolated from breeding females and males. The differential effects of the stimuli are discussed.

The Influence of Some Experiential and Genetic Factors, Including Hormones, On the Visible Courtship Behavior of Budgerigars (Melopsit Tacus)

Eight precopulatory behaviors were quantified for singly-caged, visually male and female Budgerigars that were castrated and/or given different dosages of testosterone progesterone, estradiol with or without progesterone or a placebo. Feminine soliciting for copulation seemed to be influenced mainly by blood estrogen levels, and not by other genetic and/or experiential factors associated with a feminine sexual identity. Estrogen and testosterone both stimulated to mount, but only in males. Of the remaining six typically precopulatory displays, no one factor seems to explain why, under typical breeding conditions, these precopulatory activities are observed to be performed mainly by male Budgerigars - to the extent that they have been denoted as behaviors. This study identifies three factors apart from the different and specific stimuli presented by a mate: (1) the presence of high levels of plasma gonadal hormones; (2) other genetic and/or experiential factors related to a sexual identity; and (3) an interaction of I and 2 whereby 2 prevents a greater responsiveness to hormonal stimuli. Data suggest that, when the varying and specific signals from a mate are disregarded, factor I may be most responsible for the masculine nature of Pumping and factor 2 for Bill-hooking and factor 3 for intention to mount and displays containing the nudging component, whereas those displays that also contain the Bill-hooking component seem to be associated with a baseline sexual difference and those displays that begin with Nudging followed by Pumping are stimulated by gonadal hormone levels. Thus, different interactions of hormonal and other factors associated with a sexual identity seem to influence the quantities of different precopulatory displays performed by isolated Budgerigars.

Effects of the light regime and breeding experience on budgerigar reproduction

Female budgerigars, provided with nest‐boxes and exposed to male vocalizations, lay more rapidly under a 14 L: 10 D photoregime than under regimes involving shorter light periods, though some birds will lay even when kept under continuous darkness. The photoperiod affects principally the interval between nest‐box entry and egg‐laying. Birds with previous breeding experience lay sooner than naive birds.

Hormonal and experiential factors influencing the nestbox oriented behaviour of budgerigars (Melopsittacus undulatus).

Hormonal and experiential factors influencing the nestbox oriented behaviour of budgerigars (Melopsittacus undulatus).

The W-chromosome of the budgerigar, Melopsittacus undulatus

The chromosome complement of male and female budgerigars (Melopsittacus undulatus) was studied in primary kidney cell cultures. van Brink's description of the male complement was confirmed. The 26 largest chromosomes can unequivocally be placed in 13 pairs. In the female the fifth largest chromosome is single ; it is the Z-chromosome, again confirming van Brink. In addition in all females and none of the males a previously undescribed extra chromosome was found, in size between pairs 9 and 10 with arm ratio 1∶1.5 and negatively heteropycnotic at metaphase. It is identified as the W-chromosome.