Sanjay Kumar Bhardwaj

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Two experiments studied the relative effects on body mass and testicular growth of stimulatory photoperiods applied simultaneously to two photosensitive species, the house sparrow (Passer domesticus) and brahminy myna (Sturnus pagodarum). Experiment 1 on the house sparrow consisted of two parts. In experiment 1A, beginning on 24 March 2002, short day(More)
We investigated the effects of food availability on the seasonal testicular growth in the photoperiodic house sparrow (Passer domesticus). Two experiments were performed, each lasting 4 weeks. In experiment 1, sparrows were exposed to natural (NDL; group 1), short (8L:16D; group 2) and long (16L:8D; groups 3-5) day lengths with access to food ad libitum(More)
Hypothalamic expression of the thyroid hormone (TH) responsive gonadostimulatory (eya3, cga, tshβ, dio2, dio3, gnrh, gnih) and neurosteroid pathway genes (androgen receptor [ar], aromatase [cyp19], estrogen receptor [er] α and β) was examined in photosensitive redheaded buntings exposed to 2 (acute, experiment 1) or 12 (chronic, experiment 2) long days(More)
Circadian (locomotor activity/perching) behaviour of the weaverbird (Ploceus philippinus) under different light intensities was studied. Six groups of birds were subjected to 12L:12D (L = 1000 and 10 lux and D = 0.3 lux) for two weeks, and thereafter released into constant dim illumination (LL(dim) = 0.3 lux). After two weeks of LL(dim), birds were given a(More)
Day length regulates annual reproductive cycle in many birds including subtropical Indian Weaver birds (Ploceus philippinus). We investigated whether light intensity modulated the effects of the duration of photoperiod in inducing testicular recrudescence- regression cycle, and whether such effects are influenced by the seasons. Two experiments were(More)
This study investigated whether changes in illumination modify perception of day and night conditions in a diurnal species, the Indian weaver bird. Birds were initially subjected to a 12-h light:12-h dark regime (12L:12D; L=20 lux, D =0.5 lux). After every 2 wks, the combinations of light illumination in L and D phases were changed as follows: 20:2 lux,(More)
A study was performed to investigate the effects of complete and skeleton photoperiods on gonadal stimulation in baya weaver, Ploceus philippinus. In August 2003, five groups of acclimatized birds (n = 7 each) were exposed to 6L: 13D: 1L: 4D, 6L: 6D: 1L: 11D, 11L: 13D and 13L: 11D. Birds were refractory and their exposure to 6L:13D:1L:4D, 6L:6D:1L:11D,(More)
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