Publications

2018

  • S.K.T. Taufique, A. Prabhat and V. Kumar (2018) Constant light environment suppresses maturation and reduces complexity of new born neuron processes in the hippocampus and caudal nidopallium of a diurnal corvid: Implication for impairment of the learning and cognitive performance. Neurobiology of Learning and Memory 147 (2018) 120–127
  • N. Agarwal, I. Mishra, S. Rani and V. Kumar (2018): Temporal expression of clock genes in central and peripheral tissues of spotted munia under varying light conditions: Evidence for circadian regulation of daily physiology in a nonphotoperiodic circannual songbird species, Chronobiology International, DOI: 10.1080/07420528.2017.1422742
  • Sharma A, Singh D, Das S, Kumar V. Hypothalamic and liver transcriptome from two crucial life-history stages in a migratory songbird. Exp Physiol. 2018;1–11. https://doi.org/10.1113/EP086831

2017

  • I. Mishra and V. Kumar (2017) Circadian basis of seasonal timing in higher vertebrates. Biological Rhythm Research. DOI: 10.1080/09291016.2017.1345447
  • I. Mishra, D. Singh and V. Kumar (2017) Temporal expression of c-fos and genes coding for neuropeptides and enzymes of amino acid and amine neurotransmitter biosynthesis in retina, pineal and hypothalamus of a migratory songbird: Evidence for circadian rhythm dependent seasonal responses. https://doi.org/10.1016/j.neuroscience.2017.12.016
  • A. Yadav, R. Kumar, J. Tiwari, V. Kumar and S. Rani (2017): Sleep in birds: lying on the continuum of activity and rest, Biological Rhythm Research, DOI: 10.1080/09291016.2017.1346850
  • N. Agarwal, I. Mishra, R. Komal, S. Rani and V. Kumar (2017) Circannual testis and moult cycles persist under photoperiods that disrupt circadian activity and clock gene cycles in Spotted Munia. J. Exp. Biol.
  • V. Kumar and I. Mishra (2017) Circannual Rhythms In Encyclopedia of Reproduction : Second Edition.
  • N. A. Jha and V. Kumar (2017) Effect of no-light environment on behaviour, learning performance and personality in zebra finches. Animal Behaviour 132 : 29-47.
  • I. Mishra, D. Singh and V. Kumar (2017) Daily levels and rhythms in circulating corticosterone and insulin alter with photostimulated seasonal states in night-migratory blackheaded buntings. Hormones and Behavior 114-123
  • T. Stevenson and V. Kumar (2017) Neural control of daily and seasonal timing of song bird migration. J. Comp. Physiol. A
  • V. Kumar (Editor) (2017) Biological Timekeeping: Clocks, Rhythms and Behaviour. Springer India Pvt. Ltd.
  • N. J. Gupta, V. Kumar, S. Panda (2017) A camera-phone based study reveals erratic eating pattern and disrupted daily eating-fasting cycle among adults in India. Plos One 12, 1-15.
  • I. Mishra, D. Singh and V. Kumar (2017) Seasonal alterations in the daily rhythms in hypothalamic expression of genes involved in the photoperiodic transduction and neurosteroid-dependent processes in migratory blackheaded buntings. Journal of Neuroendocrinology 29, 1-10.
  • N. A. Jha and V. Kumar (2017) Female conspecifics restore rhythmic singing behaviour in arrhythmic male Zebra finches. Journal of Biosciences 42, 139-147.
  • D. Singh, V. Kumar (2017) Extra hypothalamic brain clocks in song birds: Photoperiodic state dependent clock gene oscillation in night migratory blackheaded buntings (Emberiza melanocephala) Journal of Photochemistry and Photobiology, B: Biology 169, 13-20.

2016

  • N. A. Jha and V. Kumar (2016) Protein rich food does not affect singing behaviour and song quality in adult Zebra finches (Taeniopygia guttata) Current Science 111, 1693-96.
  • I. Mishra, S.K. Bhardwaj, S. Malik and V. Kumar (2016) Concurrent hypothalamic gene expression under acute and chronic long days: Implications for initiation and maintenance of photoperiodic response in migratory songbirds. Molecular and Cellular Endocrinology 439, 81-94.
  • SK. Taufique,V. Kumar(2016) Differential activation and tyrosine hydroxylase distribution in the hippocampal, pallial and midbrain brain regions in response to cognitive performance in Indian house crows exposed to abrupt light environment. Behavioural Brain Research 314:21-9.
  • D. Singh, N. Trivedi, S. Malik, S. Rani and V. Kumar (2016) Timed food availability affects circadian behavior but not the neuropeptide Y expression in Indian weaverbirds exposed to atypical light environment. Physiology & Behavior 161: 81-89.
  • Surbhi, A. Rastogi, S. Malik, S. Rani and V. Kumar (2016) Seasonal neuronal plasticity in song-control and auditory forebrain areas in subtropical non-migratory and Palearctic-Indian migratory male songbirds. Journal of Comparative Neurology 524: 2914-2929
  • O. P. Singh, S. Kumar, U. Singh, V. Kumar, R. Lechan and P. Singru (2016) Cocaine-and mphetamine regulated transcript peptide (CART) in the brain of zebra finch, Taeniopygiaguttata: Organization, interaction with neuropeptide Y, and response to changes in energy status. Journal of Comparative Neurology 524: 3014-3041.
  • Surbhi, A. Rastogi, S. Malik, S. Rani and V. Kumar (2016) Changes in brain peptides associated with reproduction and energy homeostasis in photosensitive and photorefractory migratory redheaded buntings. General and Comparative Endocrinology 230-231: 67-75.
  • D. Singh, N. Trivedi, S. Malik, S. Rani and V. Kumar (2016) Timed food availability affects circadian behavior but not the neuropeptide Y expression in Indian weaverbirds exposed to atypical light environment. Physiology & Behavior 161: 81-89.
  • I. Mishra, D. Singh and V. Kumar (2016) Daily expression of genes coding for neurotransmitters in central and peripheral tissues of redheaded bunting: implication for circadian regulation of physiology in songbirds. Chronobiology International 33: 280-292.
  • A. K. Trivedi, J. Kumar, S. Rani, V. Kumar (2016) Pinealectomy abolishes circadian behavior and interferes with circadian clock gene oscillations in brain and liver but not retina in a migratory songbird. Physiology & Behavior 156: 156-163.
  • S. K. T. Taufique, N. A. Jha and V. Kumar (2016) Circadian rhythm determines the timing of activity, and ingestive and grooming behaviours in Indian house crows, Corvussplendens. Current Science 110: 897-901.

2015

  • A. Rastogi, Surbhi, S. Malik, S. Rani and V. Kumar (2015) Annual life-history dependent differences in the seasonal change in neural activity of the olfactory system between non-migratory and migratory songbirds. Behavioral Brain Research 296: 233-239.
  • D. Singh, A. K. Trivedi, S. Rani, S. Panda and V. Kumar (2015) Circadian timing in central and peripheral tissues in a migratory songbird: Dependence on annual life-history states. The FASEB Journal 29: 4248-4255.
  • G. Majumdar, G. Yadav, S. Rani and V. Kumar (2015) Bird eyes distinguish summer from winter: Retinal response to acute photoperiod change in the night-migratory redheaded bunting. Journal of Chemical Neuroanatomy 68: 55-60.
  • G. Majumdar, S. Rani and V. Kumar (2015) Hypothalamic gene switches control transitions between seasonal life history states in a night-migratory photoperiodic songbird. Molecular and Cellular Endocrinology 399: 110-121.
  • Surbhi, A. Rastogi, S. Rani and V. Kumar (2015) Seasonal plasticity in the peptide neuronal systems: Potential roles of GnRH, GnIH, NPY and VIP in regulation of reproductive axis in subtropical Indian weaver birds. Journal of Neuroendocrinology 27: 357-369.
  • G. Majumdar, A. K. Trivedi, N. J. Gupta and V. Kumar (2015) Circadian synchronization determines critical day length for seasonal responses. Physiology and Behavior 47: 282-290.
  • A. K. Trivedi, J. Kumar, S. Rani and V. Kumar (2015) Adaptation of oxidative phosphorylation to photoperiod-induced seasonal metabolic states in migratory songbirds. Comparative Biochemistry Physiology AMolIntegrPhysiol 184C: 34-40.
  • S. Malik, J. Singh, A. K. Trivedi, S. Singh, S. Rani and V. Kumar (2015) Nocturnal melatonin levels decode daily light environment and reflect seasonal states in night-migratory blackheaded bunting (Emberizamelanocephala) Photochemistry and Photobiological Sciences 14: 963-971.
  • G. Yadav, S. Malik, S. Rani and V.  Kumar (2015) Role of light wavelengths in synchronization of circadian physiology in songbirds. Physiology and Behavior 140:164-171.
  • T. J. Stevenson, M. E. Visser, ………..V. Kumar,….. B. Helm (2015; multi-authored review) Disrupted seasonal biology impacts health, food security and ecosystems Proceeding of Royal Society. B. 282: 20151453. (Review).
  • V. M. Cassone and V. Kumar (2015) Circadian Rhythms. In: Sturkie’s Avian Physiology. Sixth Edition (Ed. C. G. Scanes). Elsevier (Academic Press), Amsterdam. pp. 811-828.
  • Surbhi and V. Kumar (2014) Avian photoreceptors and their role in the regulation of daily and seasonal physiology. Gen. Comp. Endocr. 220: 13-22. (Review).

2014

  • A. K. Trivedi, J. Kumar, S. Rani, V. Kumar (2014) Annual life history-dependent gene expression in the hypothalamus and liver of a migratory songbird: Insights into the molecular regulation of seasonal metabolism. J. Biol. Rhythms 29: 332-345.
  • P. Budki, S. Malik, S. Rani and V. Kumar (2014) Circadian rhythms are not involved in the regulation of circannual reproductive cycles in a sub-tropical bird, the spotted munia.  J. Exp. Biol. 217: 2569-2579.
  • Surbhi, Y. Kumari, S. Rani, K. Tsutsui and V. Kumar (2014) Duration of melatonin regulates seasonal plasticity in subtropical Indian weaver bird, Ploceusphilippinus. Gen. Comp. Endocr. 220: 46-54.
  • A. Srivastava, N. Trivedi, S. Malik, S. Rani and V. Kumar (2014) Molecular basis of photoperiodic control of reproductive cycle in a subtropical songbird, the Indian weaverbird (Ploceusphilippinus). Gen. Comp. Endocr. 220: 41-45.
  • S. Srivastava, S. Rani and V. Kumar (2014) Photoperiodic induction of pre-migratory phenotype in a migratory songbird: Identification of metabolic proteins in flight muscles. J. Comp. Physiol. B. 184: 741-751.
  • G. Majumdar, G. Yadav, S. Rani and V. Kumar (2014) A photoperiodic molecular response in migratory redheaded bunting exposed to a single long day. Gen. Comp. Endocr. 204:104-113.
  • S. Malik, S. Singh, S. Rani and V. Kumar (2014). Life at a different pace: Annual itineraries are conserved in seasonal songbirds. J. Biosci. 39: 485-491.
  • S. Malik, P. Budki, S. Rani and V. Kumar (2014) Optimization of circadian adaptation to physical enrichment: Effects on activity behavior in a subtropical songbird. J. Ornithology 155: 283-290.
  • A. K. Trivedi, S. Rani and V. Kumar (2014) Circadian adaptation to seasons: Effects on activity behavior in subtropical house sparrow, Passer domestic. Biol. Rhythm Res. 45: 465-475.
  • S. Rani and V. Kumar (2014) Photoperiodic regulation of seasonal reproduction in higher vertebrates. Indian J. of Exp. Biol. 52: 413-419.
  • S. Malik, G. Yadav, S. Rani and V. Kumar (2014) Light wavelength dependent circadian and seasonal responses in blackheaded bunting. Indian J. of Exp. Biol. 52: 448-459.
  • I. Mishra, A. K. Trivedi and V. Kumar (2014) Daily behavior can differ between colour morphs of the same species: A study on circadian activity behavior of grey and pied zebra finches. Indian J. of Exp. Biol. 52:516-520.
  • A. K. Trivedi and V. Kumar (2014) Melatonin: An internal signal for daily and seasonal timing. Indian J. Exp. Biol. 52:425-437. (Review).

2013

  • D. Singh, S. Rani and V. Kumar (2013). Daily expression of six clock genes in central and peripheral tissues of a night-migratory songbird: Evidence for tissue specific circadian timing. Chronobiol. Int. 30: 1208-1217.
  • D. Singh, Y. Kumari, A. Rastogi, S. Rani and V. Kumar (2013). Neuropeptide Y mRNA and peptide in the night-migratory redheaded bunting brain. Cell and Tissue Res. 354: 551-562.
  • A. Rastogi, Y. Kumari, S. Rani and V. Kumar (2013). Neural correlates of migration: Activation of putative hypothalamic clock(s) in and out of migratory state in the night-migratory blackheaded bunting (Emberizamelanocephala). PLoS One 8: e70065.
  • N. J. Gupta and V. Kumar (2013). Testes play a role in termination but not in initiation of the spring migration in the night-migratory blackheaded bunting. Anim. Biol. 63:321-329.
  • S. Rani and V. Kumar (2013). Avian circannual systems: persistence and sex differences. Gen. Comp. Endocrinol. 190: 61-67. (Review)

2012

  • J. Singh, P. Budki, S. Rani and V. Kumar (2012). Temperature alters the photoperiodically controlled phenologies linked with migration and reproduction in a night-migratory songbird. Proc. R. Soc. B. 279: 509-515.
  • J. Singh, A. Rastogi, S. Rani and V. Kumar (2012). Food availability affects circadian clock-controlled activity and zugunruhe in the night migratory male blackheaded bunting (Emberizamelanocephala). Chronobiology Int. 29: 15-25.
  • J. Singh, A. Rastogi, S. Rani and V. Kumar (2012) Functional similarity in relation to the external environment between circadian behavioral and melatonin rhythms in the subtropical Indian weaver bird. Horm. Behav. 61: 527-534.
  • P. Budki, S. Rani and V. Kumar (2012). Persistence of Circannual Rhythms under Constant Periodic and Aperiodic Light Conditions: Sex Differences and Relationship with the External Environment. J. Exp. Biol. 215:3774-3785.

2011

  • A. Rastogi, Y. Kumari, S. Rani and V. Kumar (2011). Phase inversion of neural activity in the olfactory and visual systems of a night-migratory bird during migration. European J. Neurosci. 34: 99-109.

2010

  • J. Singh, S. Rani, and V. Kumar (2010) Presence of a conspecific renders survival advantages in the migratory redheaded bunting: test through the effects of restricted feeding on activity pattern and survivorship. Chronobiol. Int. 27: 111-127.
  • V. Kumar, J. C. Wingfield, A. Dawson, M. Ramenofsky, S. Rani, and P. Bartell (2010). Biological Clocks and Regulation of Seasonal Reproduction and Migration in Birds. Physiol. Biochem. Zool. 83:827-35 (Review).

2009

  • S. Rani, S. Singh, S. Malik, J. Singh, and V. Kumar (2009) Synchronization of Indian weaverbird circadian rhythms to food and light zeitgebers: Role of pineal. Chronobiol. Int. 26: 653-665.
  • P. Budki, S. Rani, and V. Kumar (2009) Food deprivation during photosensitive and photorefractory life history stages affects reproductive cycle in the migratory redheaded bunting (Emberizabruniceps). J. Exp. Biol. 212:225-230.

2008

  • S. P. Karaganis, V. Kumar, P. D. Beremand, M. J. Baliey, T. L. Thomas, V. M. Cassone (2008) Circadian genomics of the chick pineal gland in vitro. BMC Genomics 9: 206.
  • V. M. Cassone, P.  A. Bartell, B. J. Earnest, V. Kumar (2008) Duration of Melatonin Regulates Seasonal Changes in Song Control Nuclei of the House Sparrow Passer domesticus: Independence from Gonads and Circadian Entrainment. J. Biol. Rhythms 23: 49-58.
  • J. Singh, P. Budki, S. Rani and V. Kumar (2008) Regulation of seasonal responses in birds: Role of photoperiod and biological clocks. Proceedings of the 4th CBP Meeting in Africa: Mara 2008, “Molecules to Migration: The Pressures of Life” Madimond, pp 487 – 496.
  • S. Rani, S. Malik, J. Singh, S. Singh and V. Kumar (2008) The photoperiodic and circadian control of migratory restlessness (Zugunruhe) in Palaearctic Indian migratory bunting: a new model to study migratory physiology. Proceedings of the 4th CBP Meeting in Africa: Mara 2008, “Molecules to Migration: The Pressures of Life”, Madimond, pp 551 – 558.

2007

  • V. Kumar, S. Rani, S. Malik, A. K. Trivedi, I. Schwabl, B. Helm, E. Gwinner (2007) Daytime light intensity affects seasonal timing via changes in the nocturnal melatonin levels. Naturwissenchaften 94: 693-696.
  • V. Kumar, T. J. Van’t Hof, and EberhardGwinner (2007) Circadian behavioral and melatonin rhythms in the European starling under light-dark cycles with steadily changing periods: Evidence for close mutual coupling? Horm. Behav. 52: 409-416.
  • S. Rani, S. Singh and V. Kumar (2007) Photoperiodism, pineal clock and seasonal reproduction in the Indian weaver bird (Ploceusphilippinus). J. Ornithology 148: 601-610.

2006

  • S. Rani, S. Malik, A. K. Trivedi, S. Singh and V. Kumar (2006) A circadian clock regulates migratory restlessness in the blackheaded bunting (Emberizamelanocephala) Current Sci. 91: 1093-1095.
  • A. K. Trivedi, S. Rani and V. Kumar (2006) Natural light restricted to twilight delays the timing of testicular regression but does not affect the timing of the daily activity rhythm of the house sparrow (Passer domesticus). BMC: J. Circa. Rhythms 4: 5.
  • A. K. Trivedi, S. Rani and V. Kumar (2006) Control of annual reproductive cycle in the subtropical house sparrow (Passer domesticus): Evidence for conservation of photoperiodic control mechanisms in birds. BMC: Frontiers in Zoology 3: 12.
  • V. Kumar, S. Rani and B. P. Singh (2006) Biological clocks help reduce the physiological conflicts in avian migrants. J. Ornithology 147: 281-286.

2005

  • S. Rani, S. Singh and V. Kumar (2005) The pineal clock affects behavioural circadian rhythms but not photoperiodic induction in the Indian weaver bird (Ploceusphilippinus). J. Ornithology 146: 355-364.
  • A. K. Trivedi, S. Rani and V. Kumar (2005) Differential responses of the photoperiodic clock in two passerine birds possessing strongly self-sustained circadian system. Chronobiol. Int. 22: 801-806.
  • V. Kumar and E. Gwinner (2005) Pinealectomy shortens resynchronisation times of house sparrow (Passer domesticus) circadian rhythms. Naturwissenschaften 92: 419-422.
  • S. Rani, S. Singh, M. Misra, S. Malik, B. P. Singh, and V. Kumar (2005) Daily light regulates seasonal responses in the migratory male redheaded bunting (Emberizabruniceps). Journal of Experimental Zoology 303A: 541-550.
  • V. Kumar and B. P. Singh (2005) The timekeeping system in birds. Proc. Indian Nat Sci. Academy B (Biological sciences) 5&6: 267-284.
  • V. M. Cassone, M. J. Bailey, S. P. Karaganis, V. Kumar and P. A. Bartell (2005) Functional Genomics of the Avian Pineal Gland. In: Avian Endocrinology (eds. P. Sharp and A. Dawson), Narosa Publ.  House.  N.  Delhi. pp. 11-26.

2004

  • A. K. Trivedi, S. Rani and V. Kumar (2004) Melatonin blocks inhibitory effects of prolactin on photoperiodic induction of gain in body mass, testicular growth and feather regeneration in the migratory male redheaded bunting (Emberizabruniceps). BMC: Reprod Biol. Endocr. 2: 79.
  • M. Misra, S. Rani, S. Singh and V. Kumar (2004) Regulation of seasonality in the migratory male blackheaded bunting (Emberizamelanocephala). Reprod. Nutr. Dev. 44: 341-352.
  • S. Malik, S. Rani and V. Kumar (2004) Wavelength dependency of light induced effects on photoperiodic clock in the migratory blackheaded bunting (Emberizamelanocephala). Chronobiol. Int. 21: 367–384.
  • V. Kumar, B. P. Singh and S. Rani (2004) The Bird Clock: A complex multi-oscillatory and highly diversified system. Biol. Rhythm Research 35: 121-144.

2002

  • S. Malik, S. Rani and V. Kumar (2002) The influence of light wavelength on phase-dependent responsiveness of the photoperiodic clock in migratory blackheaded bunting. Biol. Rhythm Res. 33: 65-73.
  • S. Singh, M. Misra, S. Rani and V. Kumar (2002) The photoperiodic entrainment and induction of the circadian clock regulating seasonal responses in the migratory blackheaded bunting. Chronobiol.  Int.  19: 865-881.
  • V. Kumar, S. Singh, M. Misra, S. Malik and S. Rani (2002) Role of melatonin in photoperiodic time measurement in the migratory redheaded bunting (Emberizabruniceps) and the nonmigratory Indian weaver bird (Ploceusphilippinus). J. Exp. Zool. 292: 277-286.
  • S. Rani, S. Singh and V. Kumar (2002) Light sensitivity of the biological clock. Biological Rhythms (ed. V. Kumar), Narosa Publishing House, New Delhi/ Springer-Verlag, Germany. pp. 232-243.

2001

  • V. Kumar, S. Singh, M. Misra and S. Malik (2001) Effects of duration and time of food availability on photoperiodic responses in the migratory male blackheaded bunting (Emberizamelanocephala). J. Exp. Biol. 204: 2843-2848.
  • S. Rani, S. Singh, M. Misra and V. Kumar (2001) The influence of light wavelength on reproductive photorefractoriness in migratory blackheaded bunting (Emberizamelanocephala). Reprod. Nutr. Dev. 41: 277-284.
  • R. Brandstaetter, V. Kumar, T. J. Van’t Hof and E. Gwinner (2001) Seasonal variations of in vivo and in vitro melatonin production in a passeriform bird, the house sparrow (Passer domesticus). J. Pineal Res. 31: 120-126.
  • V. Kumar (2001) Melatonin   and   circadian   rhythmicity   in   birds.  In: Avian Endocrinology (eds. A. Dawson & C. M. Chaturvedi), Narosa Publ.  N.  Delhi. pp 93-112.

2000

  • S. Rani and V. Kumar (2000) Phasic response of the photoperiodic clock to wavelength and intensity of light in the redheaded bunting, Emberizabruniceps. Physiol. Behav. 69: 277-283.
  • V. Kumar, S. Rani and S. Malik (2000) Wavelength of light mimics the effects of the duration and intensity of a long photoperiod in stimulation of gonadal responses in the male blackheaded bunting (Emberizamelanocephala). Curr. Sci. 79: 508-510.
  • R. Brandstaetter, V, Kumar, U. Abraham and E. Gwinner (2000) Photoperiodic information acquired and stored in vivo is retained in vitro by a circadian oscillator, the avian pineal gland. Proc. Natl. Acad. Sci. USA, 97: 12324-12328.
  • V. Kumar, E. Gwinner and T. J. Van’t Hof (2000) Circadian rhythms of melatonin in the European starling exposed to different lighting conditions: Relationship with locomotor and feeding rhythms. J. Comp. Physiol. A 186: 205-215.

1999

  • V. Kumar and S. Rani (1999) Differential responses to complete and corresponding skeleton photoperiods in male blackheaded bunting. Curr. Sci. 77: 283-285.
  • S. Rani and V. Kumar (1999) Time course of senstivity of the photoinducible phase to light in the redheaded bunting (Emberizabruniceps).  Biol. Rhythm Res. 30: 555-562.
  • V. Kumar and S. Rani (1999) Light sensitivity of the photoperiodic response system in higher vertebrates: Wavelength and intensity effects. Indian J. Exp. Biol. 37: 1053-1064.

1997

  • V. Kumar (1997) Photoperiodism in higher vertebrates: An adaptive strategy in temporal environment. Indian J. Exp. Biol. 35: 427-437.
  • V. Kumar (1997) Effects of complete and skeleton photoperiods in altering the timing of spontaneous fat depletion and gonadal regression in migratory male blackheaded bunting (Emberizamelanocephala). Indian J. Exp. Biol. 35: 1161-65.
  • V. Kumar, D. Goguen, M. E. Guido and B. Rusak (1997) Melatonin does not influence the expression of c-fos in the suprachiasmatic nucleus of rats and hamster. Mol. Brain Res. 52: 242-248.

1996

  • V. Kumar and S. Rani (1996) Effects of wavelength and intensity of light in initiation of body fattening and gonadal growth in a migratory bunting under complete and skeleton photoperiods.  Physiol. Behav. 60: 625-631.
  • V. Kumar, N. Jain and B. K. Follett (1996) The photoperiodic clock in blackheaded buntings (Emberizamelanocephala) is mediated by a self-sustaining circadian system. J. Comp. Physiol. A 179: 59-64.
  • V. Kumar (1996) Effects of melatonin in blocking the response to a skeleton photoperiod in the blackheaded bunting. Physiol. Behav. 59: 617-620.
  • V. Kumar, B. S. Kumar and N. Jain (1996) Effect of late afternoon administration of melatonin on photoperiod-induced responses in buntings. Indian J. Exp. Biol. 34: 220-225

1995

  • T. S. Juss, V. M. King, V. Kumar and B. K. Follett (1995) Does unusual entrainment of the circadian system under T36h photocycles reduce the critical daylength for photoperiodic induction in Japanese quail?  J. Biol. Rhythms 10: 17-32.
  • V. Kumar and N. Jain (1995) Circadian regulation of melatonin secretion in blackheaded buntings EmberizamelanocephalaScopoli. Indian J. Exp. Biol. 33: 333-336.
  • V. Kumar and G. A. Lincoln (1995) Effects of a one-hour light pulse on the timing of the circadian rhythm in melatonin secretion in rams. J. Pineal. Res. 18: 21-27.
  •  N. Jain and V. Kumar (1995) Changes in food intake, body weight, gonads and plasma concentrations of thyroxine, luteinizing hormone and testosterone in captive male buntings exposed to natural daylengths at 29oN. J. Biosci. 20: 417-426.
  • V. Kumar and B. S. Kumar (1995) Entrainment of circadian system under variable photocycles (T-photocycles) alters the critical daylength for photoperiodic induction in blackheaded buntings. J. Exp. Zool. 273: 297-302.

1994

  • V. Kumar, N. Jain and B. P. Singh (1994) Nature of circadian rhythm of photoperiodic photosensitivity in the blackheaded buntings (Emberizamelanocephala). Indian J. Exp. Biol. 32: 789-792.

1993

  • B. S. Kumar and V. Kumar (1993) Photoperiodic control of annual reproductive cycle in subtropical brahminy myna, Sturnuspagodarum. Gen. Comp. Endocrinol. 89: 149-160.
  • V. Kumar and B. K. Follett (1993) The circadian nature of melatonin secretion in Japanese quail (Coturnixcoturnix japonica). J. Pineal Res. 14: 192-200.
  • V. Kumar, N. Jain, B. P. Singh and B. S. Kumar (1993) Plasma levels of luteinizing hormone in intact and castrated photosensitive blackheaded bunting (Emberizamelanocephala) exposed to stimulatory and nonstimulatory photoperiods. Reprod. Nutr. Dev. 33: 143-150.
  • V. Kumar, G. A. Lincoln and D. J. Tortonese (1993) Effects of excitatory amino acid receptor agonists and antagonists on the secretion of melatonin, luteinizing hormone and prolactin in the ram. J.  Neuroendocrinol. 5: 649-654.
  • V. Kumar and B. K. Follett (1993) The nature of the photoperiodic clock in vertebrates. Proc. Zool. Soc. Calcutta (J. B. S. Haldane Commemoration Vol.) pp 217-227.
  • V. Kumar, T. S. Juss and B. K. Follett (1993) Melatonin secretion in quail provides a seasonal calendar but not one used for photoperiodic time-measurement. In: Melatonin and the Pineal Gland – from Basic Science to Clinical Application (eds. Y. Touitou, J. Arendt and P. Pevet), Elsevier Science Publ., pp. 163-168.

1992

  • V. Kumar and B. S. Kumar (1992) Termination of photorefractoriness in the brahminy myna, Sturnuspagodarum: Role of photoperiods and gonadal hormones. Indian J. Exp. Biol. 30: 48-53.
  • V. Kumar, B. S. Kumar and B. P. Singh (1992) Photostimulation of blackheaded bunting: Subjective interpretation of day and night depends upon both photophase contrast and light intensity. Physiol. Behav. 51: 1213-1217.
  • T. S. Juss, V. Kumar and B. K. Follett (1992) Melatonin secretion in birds: A seasonal calendar not used for photoperiodic time measurement. Neuroscience Letters 42 (suppl.): 45.
  • B. K. Follett, V. Kumar and T. S. Juss (1992) Circadian nature of the photoperiodic clock in Japanese quail. J. Comp. Physiol. A. 171: 533-540.

1991

  • B. S. Kumar and V. Kumar (1991) Seasonal reproduction in a tropical myna, Sturnuspagodarum: Role of photoperiod. Gen. Comp. Endocrinol. 83: 354-365.
  • V. Kumar and B. S. Kumar (1991) The development of photorefractoriness in termination of the breeding season in the tropical brahminy myna: Role of photoperiod. Reprod. Nutr. Dev. 31: 27-36.
  • V. Kumar, B. S. Kumar, B. P. Singh and A. Sarkar (1991) A common functional basis for the photoperiodic mechanism regulating reproductive and metabolic responses in the migratory redheaded bunting. Period. Biolog. 93: 169-174.

1990

  • V. Kumar and B. S. Kumar (1990) Effects of testosterone on the testes, body weight and plumage regeneration in photorefractory male redheaded bunting, Emberizabruniceps. Indian J. Exp.Biol. 28: 417-420.
  • V. Kumar and B. S. Kumar (1990) Effects of photoperiod, gonadectomy and testosterone therapy on food intake and body weight in male redheaded bunting, Emberizabruniceps. J. Reprod. Biol. Comp. Endocrinol. 2: 80-87.

1989

  • V. Kumar and S. Tiwari (1989) Response to experimental photoperiods by an estrilid finch the white throated munia (Lonchuramalabarica). J. Zool. Soc. India 40: 13-20.

1988

  • V. Kumar (1988) Investigations of photoperiodically induced fattening in migratory     blackheaded bunting (Emberizamelanocephala) (Aves). J. Zool. (London) 216: 253-263.

1986

  • V. Kumar (1986) Carry-over effects of long and short and short photoperiods on body fattening and gonadal weight of blackheaded bunting, (Emberizamelanocephala). Acta Physiol. Hungarica 67: 193-198.
  • V. Kumar (1986) The photoperiodic entrainment and induction of reproductive rhythms in male blackheaded buntings (Emberizamelanocephala). Chronobiol. Int. 3: 165-170.

1985

  • V. Kumar, P. D. Tewary and A. S. Dixit (1985) Participation of the circadian component in the photoperiodic mechanism of the blackheaded bunting Emberizamelanocephala. Anim. Reprod. Sci. 9: 375-382.
  • V. Kumar and P. D. Tewary (1985) The seasonal gonadal and body weight cycles of migratory rosefinch (Carpodacuserythrinus) at Varanasi in relation to environmental factors. Indian J. Zool. 13: 25-31.

1984

  • V. Kumar and P. D. Tewary (1984) Circadian rhythmicity and the termination of photorefractoriness in the blackheaded bunting. Condor 86: 27-29.
  •  P. D. Tewary and V. Kumar (1984) Control of testes function in blackheaded bunting, Emberizamelanocephala. Curr. Sci. 53: 113-114
  • P. D. Tewary ,V. Kumar and B. K. Tripathi (1984) Response to exogenous prolactin during gonadal photostimulation in blackheaded bunting. Curr. Sci. 53: 1307-1308.
  •  P. D. Tewary, A. S. Dixit and V. Kumar (1984) Circadian rhythmicity and the initiation of reproductive functions in female passerines. Physiol. Zool. 57: 563-566.

1983

  •  P. D. Tewary, V. Kumar and B. N. Prasad (1983) Influence of photoperiod in a subtropical migratory finch, the common Indian rosefinch, Carpodacuserythrinus. Ibis 125: 115-120.
  • V. Kumar and P. D. Tewary (1983) Response to experimental photoperiods by a migratory bunting, Emberizamelanocephala. Ibis 125: 305-312.
  • P. D. Tewary, V. Kumar and V. P. Srivastava (1983) Photoperiodically induced ovarian growth in common Indian rosefinch (Carpodacuserythrinus). Comp. Physiol. Ecol. 8: 234-236.
  •  P. D. Tewary and V. Kumar (1983) Biochronometry of photoperiodically induced fat deposition in a migratory finch, the blackheaded bunting (Emberizamelanocephala) (Aves). J. Zool. (London) 200: 421-430.
  • V. Kumar, P. D. Tewary and P. M. Tripathi (1983) Photoperiodicity in the male rosefinch. Experientia 39: 1101-1102.
  •  P. D. Tewary, B. K. Tripathi and V. Kumar (1983) Effects of exogenous prolactin on ovarian growth and fattening in the redheaded bunting, Emberizabruniceps. Gen. Comp. Endocrinol. 52: 315-318.
  •  P. D. Tewary and V. Kumar (1983) Effect of light on the gonad and body weight in crested bunting (Melophuslathami). Environ. Control in Biol. 21: 7-10.

1982

  • P. D. Tewary and V. Kumar (1982) Photoperiodic responses of a subtropical migratory finch, the blackheaded bunting (Emberizamelanocephala). Condor 84: 168-171.
  • V. Kumar and P. D. Tewary (1982) Photoperiodic testicular response and photorefractoriness in common Indian rosefinch. Environ. Control in Biol. 20: 39-42.
  •  P. D. Tewary, B. N. Prasad and V. Kumar (1982) Circadian basis of photoperiodically induced testicular growth in redheaded bunting, Emberizabruniceps. Anim. Reprod. Sci. 4:
  • V. Kumar and P. D. Tewary (1982) Circadian basis for the photoperiodic response in the male blackheaded bunting (Emberizamelanocephala). Proc. Indian Acad. Sci. 91: 357-360.
  •  P. D. Tewary and V. Kumar (1982) Evidence for a circadian component in the photoperiodic mechanism of the blackheaded bunting, Emberizamelanocephala. Anim. Reprod.Sci.5: 65-73.
  • V. Kumar and P. D. Tewary (1982) Circadian function in the photoperiodic induction of the testicular growth in common Indian  rosefinch,  Carpodacuserythrinus. Anim. Reprod. Sci. 5: 223-228.
  •  B. N. Prasad, V. Kumar and P. D. Tewary (1982) Thephotogonadal response of a migratory bunting: Evidence of an external coincidence system. J. Exp. Zool. 221:131-135.
  • V. Kumar and P. D. Tewary (1982) Photoperiodic regulation of the gonadal recrudescence in common Indian rosefinch: Dependence on circadian rhythms. J. Exp. Zool. 223: 37-40.

1981

  •  P. D. Tewary and V. Kumar (1981) Circadian periodicity and the initiation of gonadal growth in male blackheaded buntings (Emberizamelanocephala). J. Comp. Physiol. 144: 201-203.
  •  P. D. Tewary and V. Kumar (1981) Involvement of circadian rhythm in photoperiodic response in the male common Indian rosefinchCarpodacuserythrinus. Indian J. Exp. Biol. 19: 77-79.
  •  P. D. Tewary and V. Kumar (1981) Effect of castration on photoperiodically induced weight gain in a migratory finch: Blackheaded bunting Emberizamelanocephala. Indian J. Exp. Biol. 19: 469-471.

BOOK CHAPETRS AND ARTICLES

2008

  • J. Singh, P. Budki, S. Rani and V. Kumar (2008) Regulation of seasonal responses in birds: Role of photoperiod and biological clocks. Proceedings of the 4th CBP Meeting in Africa: Mara 2008, “Molecules to Migration: The Pressures of Life” Madimond, pp 487 – 496.
  • S. Rani, S. Malik, J. Singh, S. Singh and V. Kumar (2008) The photoperiodic and circadian control of migratory restlessness (Zugunruhe) in Palaearctic Indian migratory bunting: a new model to study migratory physiology. Proceedings of the 4th CBP Meeting in Africa: Mara 2008, “Molecules to Migration: The Pressures of Life”, Madimond, pp 551 – 558.

2005

  • V. M. Cassone, M. J. Bailey, S. P. Karaganis, V. Kumar and P. A. Bartell (2005) Functional Genomics of the Avian Pineal Gland. In: Avian Endocrinology (eds. P. Sharp and A. Dawson), Narosa Publ. House. N. Delhi. pp. 11-26.
  • V. Kumar (2005) Vertebrate circadian clock research: Do experiments on birds and lower vertebrates promise better insights. Curr. Sci. 89: 743-746.

2002

  • S. Rani, S. Singh and V. Kumar (2002) Light sensitivity of the biological clock. Biological Rhythms (ed. V. Kumar), Narosa Publishing House, New Delhi/ Springer-Verlag, Germany. pp. 232-243.
  • S. Rani, S. Singh, A. K. Trivedi and V. Kumar (2002) Photoperiodism in Birds: An Ecological Perspective. Prof. S. B. Singh Comm. Vol. Zool. Soc. India Publ., pp 65-76.

2001

  • V. Kumar (2001) Melatonin and circadian rhythmicity in birds. In: Avian Endocrinology (eds. A. Dawson & C. M. Chaturvedi), Narosa Publ. N. Delhi. pp 93-112.

1997

  • V. Kumar (1997) Photoperiodism in Vertebrates. In: Frontiers in Environmental and Metabolic Endocrinology” (Ed. S. K. Maitra), The Univ. Burdwan Publ., India, pp. 59-66.

1993

  • V. Kumar and B. K. Follett (1993) The nature of the photoperiodic clock in vertebrates. Proc. Zool. Soc. Calcutta (J. B. S. Haldane Commemoration Vol.) pp 217-227.
  • V. Kumar, T. S. Juss and B. K. Follett (1993) Melatonin secretion in quail provides a seasonal calendar but not one used for photoperiodic time-measurement. In: Melatonin and the Pineal Gland – from Basic Science to Clinical Application (eds. Y. Touitou, J. Arendt and P. Pevet), Elsevier Science Publ., pp. 163-168.