Testes play a role in termination but not in initiation of the spring migration in the night-migratory blackheaded bunting

2013 ◽  
Vol 63 (3) ◽  
pp. 321-329 ◽  
Author(s):  
Neelu Jain Gupta ◽  
Vinod Kumar
Keyword(s):  
Spring Migration ◽  
Day Length ◽  
Gonadal Growth ◽  
Migratory Season ◽  
The Times ◽  
Blackheaded Bunting ◽  
Emberiza Melanocephala ◽  
Short Days ◽  
Migratory Phenotype

Day length regulates the development of seasonal phenotypes linked with both the spring migration (e.g., premigratory body fattening and intense nighttime restlessness, called Zugunruhe, in captive birds) and reproduction (e.g., gonadal growth and maturation). The apparent overlap in these photoinduced seasonal phenotypes could be taken to suggest that they are causally linked. The present study investigates this, using the night-migratory blackheaded bunting (Emberiza melanocephala). We continuously monitored activity of male buntings exposed for 19 weeks to short (8 h light : 16 h darkness; 8L : 16D) and long (16L : 8D) photoperiods. Long, but not short, days induced the spring migratory phenotype. Another experiment investigated the role of testes in spring migration by comparing the development of Zugunruhe between intact and castrated buntings held on natural day lengths, at Meerut (India, 29°01′N, 77°45′E) during the period from March to October, thus covering the times of both the spring and autumn migrations. Testes were not involved in induction of the migratory phenotype but probably influenced the end of the migratory season, since castrates delayed the termination of the Zugunruhe.

scholarly journals Increasing photoperiod stimulates the initiation of spring migratory behaviour and physiology in a facultative migrant, the pine siskin

2018 ◽  
Vol 5 (8) ◽  
pp. 180876 ◽  
Author(s):  
Ashley R. Robart ◽  
Mali M. K. McGuire ◽  
Heather E. Watts
Keyword(s):  
Experimental Test ◽  
Spring Migration ◽  
Fat Deposition ◽  
Day Length ◽  
Environmental Cues ◽  
Migratory Restlessness ◽  
Migratory Behaviour ◽  
Behavioural Changes ◽  
Short Day

The transition to a migratory state involves coordinated changes in physiology and behaviour. In species with regular, predictable (obligate) migrations, increasing day length triggers the expression of a spring migratory state and androgens play an important role in stimulating its development. By contrast, we know little about the environmental cues and endocrine mechanisms that regulate migration in species with less predictable (facultative) migrations. Here, we tested whether photoperiod stimulates a migratory state in a facultative nomadic migrant, the pine siskin ( Spinus pinus ). We exposed wintering birds to either a naturally increasing or short-day photoperiod and measured physiological and behavioural changes indicative of a migratory state. We also examined changes in circulating hormones that may play a role in the migratory transition. Natural-day, but not short-day, birds displayed physiological preparations for migration, including increases in fat deposition, and showed increased levels of migratory restlessness. We found no evidence for a role of corticosterone in the migratory transition, but testosterone may be important. This study is the first experimental test of the role of photoperiod in regulating facultative migration and demonstrates that the predictive cue used by many obligate migrants to time spring migration is also important in a facultative migrant.

Flower initiation in Trifolium subterraneum L. II. Limitations by vernalization, low temperatures, and photoperiod, in the field at Canberra

1959 ◽  
Vol 10 (1) ◽  
pp. 17 ◽  
Author(s):  
FHW Morley ◽  
LT Evans
Keyword(s):  
High Temperatures ◽  
Low Temperatures ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Day Length ◽  
Flower Initiation ◽  
Inhibitory Effects ◽  
Low Field ◽  
The Times ◽  
Short Days

At various times throughout the winter, autumn-sown plants of five strains of subterranean clover were removed from the field to a series of day length and temperature treatments. The times to inflorescence initiation in all treatments were determined by dissection. As vernalization proceeded the requirement of all strains for long days was progressively reduced until, by midwinter, several strains had become virtually independent of day length. Similarly, with the progress of vernalization the inhibitory effects of high temperatures during short days became progressively less marked. Whereas exposure to long days at high temperatures greatly accelerated inflorescence initiation in all strains, long days at low field temperatures had little effect. Evidence is presented which suggests that the limiting effect of very low temperatures on initiation is due not only to retardation of the rate of inflorescence primordium formation (realization), but also to limitation of an inductive process other than vernalization and dark period inhibition. The flowering behaviour of the various strains is discussed in terms of their responses to the partial processes leading to inflorescence initiation, and the interrelationships of these processes are considered.

scholarly journals The Role of Melatonin in Ewes Reproduction: a Review

2019 ◽  
Vol 12 (2) ◽  
Keyword(s):  
Physiological Role ◽  
Early Spring ◽  
Day Length ◽  
Late Winter ◽  
Seasonal Reproduction ◽  
Gnrh Secretion ◽  
Reproductive Activities ◽  
Short Days

This review was assigned to illustrate the melatonin (MLT) effect on reproduction in sheep (ewes). However, the pathway by which MLT charge the seasonal reproduction are imperfectly understood in sheep, the researchers consents that MLT regulates reproduction under influence of day length (photoperiod) to guarantee that birth happen in appropriate date of the year, it’s called neuro-endocrine process. This mechanism mediates by the pineal hormone (MLT). The major role of MLT in ewes is to translate the photo signals into endocrine pulses (gonadotropin-releasing hormone (GnRH) secretion) at the end of the retino-pineal pathway. In sheep, the MLT receptors distributed in premammillary hypothalamus (PMH), pituitary gland and Suprachiasmatic nucleus (SCN), therefore, many brain loci are participating for MLT pathways to modify the seasonal reproduction. Melatonin stimulates GnRH secretion through effect in different regions and neurons in hypothalamus such as a pre-mammillary nucleus, Arcuate and several factors like kisspeptin, RF-amide related peptide-3 (RFRP-3) and Tyrosine Hydroxylase (TH). In addition, its indirectly control prolactin (PRL) output via an effect on Tuberalin release, which is mediate the mechanism of MLT activity on pituitary PRL secretion and regulate his seasonal cyclicity. The alter in day length is the principle ecological factor that control the breeding in seasonal domestic animals. Several reproductive activities are related to short days and begin during autumn when the day becomes short and a decline in temperature (short-day breeder). While expanding in the duration of light lead to a cessation in reproduction activities during late winter and early spring. In conclusion, according to the major physiological role of MLT, it can be used in different aspects in ewes reproduction industry such as induce oestrus, increment the ovulation rate and In vitro embryo production.

cAbdullah Yūsuf cAlī & Muhammad Asad: Two Approaches to the English Translation of the Qur'an

2000 ◽  
Vol 2 (1) ◽  
pp. 107-123 ◽  
Author(s):  
Muzaffar Iqbal
Keyword(s):  
Twentieth Century ◽  
Comparative Study ◽  
Life Experiences ◽  
Academic Career ◽  
British India ◽  
Human Understanding ◽  
English Translations ◽  
Political Milieu ◽  
The Times

This article attempts to present a comparative study of the role of two twentieth-century English translations of the Qur'an: cAbdullah Yūsuf cAlī's The Meaning of the Glorious Qur'ān and Muḥammad Asad's The Message of the Qur'ān. No two men could have been more different in their background, social and political milieu and life experiences than Yūsuf cAlī and Asad. Yūsuf 'Alī was born and raised in British India and had a brilliant but traditional middle-class academic career. Asad traversed a vast cultural and geographical terrain: from a highly-disciplined childhood in Europe to the deserts of Arabia. Both men lived ‘intensely’ and with deep spiritual yearning. At some time in each of their lives they decided to embark upon the translation of the Qur'an. Their efforts have provided us with two incredibly rich monumental works, which both reflect their own unique approaches and the effects of the times and circumstances in which they lived. A comparative study of these two translations can provide rich insights into the exegesis and the phenomenon of human understanding of the divine text.

Reaktualisasi Proses Penyidikan oleh Kepolisian Berbasis Nilai-Nilai Pancasila dan Optimalisasi Pemanfaatan Teknologi

Jurnal Hukum ◽  
2016 ◽  
Vol 31 (2) ◽  
pp. 1737
Author(s):  
Ira Alia Maerani
Keyword(s):  
Criminal Justice ◽  
Rule Of Law ◽  
Justice System ◽  
Public Prosecutor ◽  
Public Confidence ◽  
The Rule Of Law ◽  
Positive Law ◽  
Use Of Technology ◽  
The Times

Abstract                Indonesian Criminal Justice System consists of the police, public prosecutor and the courts. The role of the police investigators is certainly vital as the frontline in building public confidence in the rule of law in Indonesia. The role of the investigator is quite important in realizing society’s  justice. The era of globalization requires a pattern fast-paced, instant, measurable, and transparent of life and it requires investigators to follow the times by optimizing the use of technology. The aim of this study is to give effect to the rule of law in Indonesia that provides fairness, expediency and certainty. However, it considers to have priority of Pancasila values in the process of inquiry and investigation. The values of supreme divinity, God (religious), humanity, unity, democracy and justice are values that establish a balance (harmony) in enforcing the law. Law and its implementation can create product which meets the demands for social justice. This paper will examine the role of the investigator according to positive law currently in force as well as the role of investigator in implementing the values of Pancasila, accompanied by optimizing the use of technology. Keywords: Re-actualizing, Investigation, Police, values of Pancasila, Technology   AbstrakSistem Peradilan Pidana Indonesia meliputi institusi kepolisian, kejaksaan, dan pengadilan. Peran penyidik dalam institusi kepolisian tentunya amat vital sebagai garda terdepan dalam membangun kepercayaan masyarakat terhadap penegakan hukum di Indonesia. Peran penyidik amat besar dalam terwujudnya keadilan di masyarakat. Era globalisasi yang menuntut pola kehidupan yang serba cepat, instan, terukur, dan transparan menuntut penyidik untuk mengikuti perkembangan zaman dengan mengoptimalkan pemanfaatan teknologi. Tujuannya adalah untuk memberikan arti bagi penegakan hukum di Indonesia yakni memberikan keadilan, kemanfaatan, dan kepastian. Namun yang harus diperhatikan adalah mengutamakan nilai-nilai Pancasila dalam melakukan proses penyelidikan dan penyidikan. Nilai-nilai ketuhanan yang maha esa (religius), kemanusiaan, persatuan, kerakyatan dan keadilan merupakan nilai-nilai yang membangun keseimbangan (harmoni) dalam menegakkan hukum. Sehingga produk hukum dan pelaksanaannya memenuhi rasa keadilan masyarakat. Tulisan ini akan mengkaji tentang peran penyidik menurut hukum positif yang saat ini berlaku serta peran penyidik dalam mengimplementasikan  nilai-nilai Pancasila dengan diiringi optimalisasi pemanfaatan teknologi.Kata Kunci: Reaktualisasi,Penyidikan,Kepolisian,Nilai-nilai Pancasila,Teknologi

Pondok Pesantren Sebagai Lembaga Pendidikan Alternatif

KUTTAB ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 50-57
Author(s):  
Salman Zahidi
Keyword(s):  
Cultural Identity ◽  
Boarding Schools ◽  
Islamic Education ◽  
Educational Institutions ◽  
Learning Models ◽  
Literature Study ◽  
Exploratory Approach ◽  
The Times ◽  
Modern Era

Ali Bin Abi Talib once said that children should be educated in accordance with the  development of the times. The Ali bin Abi Talib’s statement could be considered as his attention more to the development of human civilization. For that reason, there should be studies focused on the role of educational institutions in facing the challenges of the times. On this stand, the writer raises the existence of pesantren (Islamic boarding schools) for being considered to have been able to survive amid the onslaught of civilization increasingly obscuring cultural identity. In addition, this study also aims to identify and discuss the role of pesantren in the modern era. This is a literature study using a descriptive and exploratory approach. It can be concluded that pesantren are non-formal Islamic educational institutions. Pesantren have permanent and distictive methods and learning models. The purpose of pesantren education is the same as Islamic education in general, instilling a sense of virtue, familiarizing themselves with courtesy, preparing for a holy, sincere and honest life entirely. Pesantren could be seen from three aspects: (a) pesantren that are seen from facilities and infrastructures, (b) pesantren that are seen from disciplines taught, and (c) pesantren that are seen from the fields of knowledge.

scholarly journals A Revised and Improved Version of the Northern Wheatear (Oenanthe oenanthe) Transcriptome

Diversity ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 151
Author(s):  
Roberto Carlos Frias-Soler ◽  
Lilian Villarín Pildaín ◽  
Michael Wink ◽  
Franz Bairlein
Keyword(s):  
Quality Parameters ◽  
Northern Wheatear ◽  
Long Distance ◽  
Assembly Quality ◽  
Oenanthe Oenanthe ◽  
Mrna Sequencing ◽  
Sequencing Coverage ◽  
Muscle Tissues ◽  
Migratory Season ◽  
Migratory Phenotype

This work presents an updated and more complete version of the transcriptome of a long-distance migrant, the Northern Wheatear (Oenanthe oenanthe). The improved transcriptome was produced from the independent mRNA sequencing of adipose tissue, brain, intestines, liver, skin, and muscle tissues sampled during the autumnal migratory season. This new transcriptome has better sequencing coverage and is more representative of the species’ migratory phenotype. We assembled 20,248 transcripts grouped into 16,430 genes, from which 78% were successfully annotated. All the standard assembly quality parameters were improved in the second transcriptome version.

Pineal denervation by cervical sympathetic ganglionectomy suppresses the role of photoperiod on pregnancy or pseudopregnancy, body weight and moulting periods in the mink (Mustela vison)

1985 ◽  
Vol 107 (1) ◽  
pp. 31-39 ◽  
Author(s):  
L. Martinet ◽  
D. Allain ◽  
Y. Chabi
Keyword(s):  
Body Weight ◽  
Environmental Factors ◽  
Prolactin Secretion ◽  
Corpora Lutea ◽  
Progesterone Secretion ◽  
Cervical Ganglion ◽  
Cervical Sympathetic ◽  
Implantation Period ◽  
Short Days

ABSTRACT In mink, termination of the delayed implantation period, following reactivation of the corpora lutea, and onset of the spring moult are associated with a rise in prolactin secretion triggered by increasing daylength, while decreasing daylength induces the autumn moult. To establish whether suppression of the function of the pineal rendered the mink unresponsive to daylength changes, the superior cervical ganglion was removed bilaterally 2–4 weeks before mating. Intact and operated females were then left outdoors or were put under a lighting regime of either 15 h light: 9 h darkness (15L: 9D) or 8L: 16D. In July, at the end of the spring moult, the 15L: 9D lighting regime was changed to one of 8L: 16D. Under artificial photoperiods ganglionectomy suppressed the stimulatory role of long days and the inhibitory role of short days on prolactin secretion, and consequently on progesterone secretion and spring moult. Neither was the autumn moult, induced early in intact females by the change to a short photoperiod, advanced in ganglionectomized females, showing that the latter were unresponsive to the artificial modification of the photoperiod. However, in animals kept outdoors, prolactin and progesterone secretion and spring moult were not changed by ganglionectomy. Increase in body weight and autumn moult were only slightly delayed by the operation suggesting that other environmental factors had replaced the synchronizing effect of the daylength changes. Alternatively the desynchronization between intact females responsive to photoperiodism and those rendered unresponsive may be too slow to be observed soon after ganglionectomy. J. Endocr. (1985) 107, 31–39

INFLUENCE OF PHOTOPERIOD ON THYROTROPIN RELEASING HORMONE-INDUCED PROLACTIN RELEASE IN EWES

1983 ◽  
Vol 63 (1) ◽  
pp. 67-73 ◽  
Author(s):  
B. E. HOWLAND ◽  
D. SONYA ◽  
L. M. SANFORD ◽  
W. M. PALMER
Keyword(s):  
Thyrotropin Releasing Hormone ◽  
Day Length ◽  
Constant Light ◽  
Serum Prolactin ◽  
Prolactin Release ◽  
Blood Samples ◽  
Releasing Hormone ◽  
Before And After ◽  
Release Curve ◽  
Short Days

The influence of photoperiod on serum prolactin levels and prolactin release induced by thyrotropin releasing hormone (TRH) was determined in ewes maintained under the following lighting regimes: Room 1, lighting mimicked natural changes in photoperiod; Room 2, annual photoperiod changes condensed into 6 mo with short days in June; Room 3, same as Room 2 except photoperiod changed abruptly from 16.5 to 8.0 h on 21 Mar. and back to 16.5 h on 21 June; Room 4, constant light. Weekly blood samples were obtained from February to August. Additionally, blood samples were collected before and after treatment with 10 μg TRH on 19 May, 13 June, 27 June and 19 July. Prolactin levels were elevated in ewes exposed to long days or constant light. The mean of all pre-TRH samples was significantly correlated with stress-induced elevations in prolactin (highest pre-TRH value) (r = 0.72) and area under the TRH-induced release curve (r = 0.56). The prolactin release in response to TRH was greatest in ewes exposed to long days or constant light. Abrupt increase of day length elevated pretreatment prolactin levels (P < 0.01) and increased area under the response curve (P < 0.05). Key words: Photoperiod, TRH, prolactin, ewes

Sign in / Sign up

Export Citation Format

Share Document