Heat Stress and Hormones

  • Anjali Aggarwal
  • Ramesh Upadhyay


Activation of the hypothalamic–pituitary–adrenal axis and the consequent increase in plasma glucocorticoid concentrations are two of the most important responses of the animals to heat stress. The short- and long-term environmental heat affects endocrine glands and in turn release of hormones, namely, thyroxine, cortisol, growth hormone and catecholamines. Some of them result in initial increase due to acute stressors and a decline in plasma levels after prolonged exposure to stressors has been observed. The relationship of amounts in plasma of these hormones to milk production appears to be related directly for cortisol, growth hormone and prolactin with an inverse relationship with thyroxine. Epinephrine and norepinephrine are elevated with prolonged environmental heat stress. Hormones in plasma are important as potential indicators of the physiological status of a cow and reflect the physiological compensations a cow undergoes at various stages of lactation and exposure to heat stress. The plasma thyroxine (T4) and triiodothyronine (T3) levels have been observed to decline under heat stress as compared to thermoneutral conditions. The decline in thyroid hormones along with decreased plasma growth hormone (GH) level has a synergistic effect to reduce heat production. A reduced secretion of GH is required for survival of the homeotherm during heat stress. The concentration of insulin-like growth factor-1 (IGF-1) has been observed to decrease during the summer months. Aldosterone concentration declines due to a fall in serum K levels and increased excretion in sweat during heat stress. Heat stress has a detrimental effect on animal reproduction partly by disrupting the normal release of gonadotrophin-releasing hormone from the hypothalamus and luteinising hormone (LH) and follicle-stimulating hormone from the anterior pituitary gland. Heat stress reduces the degree of dominance of the selected follicle as reduced steroidogenic capacity of its theca and granulosa cells and a fall in blood oestradiol concentrations. Plasma progesterone levels may be increased or decreased depending on whether the heat stress is acute or chronic and also on the metabolic state of the animal. Insufficient progesterone secretion by the corpus luteum during summer is a probable reason of low fertility in cattle and buffalo during summer months in tropical climates.


Heat Stress Luteinising Hormone Granulosa Cell Corpus Luteum Follicular Fluid 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


  1. Abdalla EB, Kotby EA, DJohnson H (1989) Environmental heat effects on metabolic and hormonal functions and milk yield of lactating ewes. J Dairy Sci 72:471 (Abstract)Google Scholar
  2. Abdalla EB, Johnson HD, Kotby EA (1991) Hormonal adjustments during heat exposure in pregnant and lactating ewes. J Dairy Sci 74:145 (Abstract)Google Scholar
  3. Abdel-Samee AM, Habeeb AAM, Kamal TH, Abdel-Razik MA (1989) The role of urea and mineral mixture supplementation in improving productivity of heat-stressed Friesian calves in the sub-tropics. In: Proceedings of 3rd Egyptian–British conference on animal, fish and poultry production, Alexandria University, Alexandria, vol 2, pp 637–641Google Scholar
  4. Abilay TA, Johnson HD, Madan M (1975a) Influence of environmental heat on peripheral plasma progesterone and cortisol during the bovine estrous cycle. J Dairy Sci 58:1836–1840Google Scholar
  5. Abilay TA, Mitra R, Johnson HD (1975b) Plasma cortisol and total progesterone levels in Holstein steers during acute exposure to high environmental temperature (42°C) conditions. J Anim Sci 41:113–118Google Scholar
  6. Aboul-Naga AI (1987) The role of aldosterone in improving productivity of heat stressed farm animals with different technique. PhD thesis, Faculty of Agriculture, Zagazig University, ZagazigGoogle Scholar
  7. Adams JM, Cory S (1998) The Bcl-2 protein family: arbiters of cell survival. Science 281:1322–1326Google Scholar
  8. Agarwal SK, Marshall GD Jr (2001) Dexamethasone promotes type 2 cytokine production primarily through inhibition of type 1 cytokines. J Interferon Cytokine Res 21:147–155Google Scholar
  9. Aggarwal A (2004) Effect of environment on hormones, blood metabolites, milk production and composition under two sets of management in cows and buffaloes. PhD thesis submitted to National Dairy Research Institute, Karnal (Haryana), IndiaGoogle Scholar
  10. Aggarwal A, Singh M (2009) Changes in hormonal levels during early lactation in summer calving cows kept under mist cooling system. Indian J Anim Nutr 26:337–340Google Scholar
  11. Aggarwal A, Singh M (2010) Hormonal changes in heat stressed Murrah buffaloes under two different cooling systems. Buffalo Bull 29:1–6Google Scholar
  12. Aggarwal A, Upadhyay RC, Singh SV, Kumar P (2005) Adrenal-thyroid pineal interaction and effect of exogenous melatonin during summer in crossbred cattle. Indian J Anim Sci 75:915–921Google Scholar
  13. Aggarwal A, Ashutosh, Kaur H, Mani V (2010) Effect of vitamin E supplementation on leptin and insulin hormones in crossbred and indigenous cows. Annual report. National Dairy Research Institute, Karnal, HaryanaGoogle Scholar
  14. Ahmad N, Schrick FN, Butcher RL, Inskeep EK (1995) Effect of persistent follicles on early embryonic losses in beef cows. Biol Reprod 52:1129–1135Google Scholar
  15. Ailhaud G (2006) Adipose tissue as a secretory organ: from adipogenesis to the metabolic syndrome. Comptes Rendus Biologies 329:570–577Google Scholar
  16. Al-Katanani YM, Webb DW, Hansen PJ (1999) Factors affecting seasonal variation in non-return rate to first service in lactating Holstein cow in a hot climate. J Dairy Sci 82:2611–2616Google Scholar
  17. Allen TE, Bligh J (1969) A comparative study of the temporal patterns of cutaneous water vapor loss from some domesticated mammals with epithelial sweat glands. Comp Biochem Physiol 31:347Google Scholar
  18. Alvarez MB, Johnson HD (1973) Environmental heat exposure on cattle plasma catecholamine and glucocorticoids. J Dairy Sci 56:189–194Google Scholar
  19. Ambati S, Kim HK, Yang JY, Lin J, Della-Fera MA, Baile CA (2007) Effects of leptin on apoptosis and adipogenesis in 3T3-L1 adipocytes. Biochem Pharmacol 73:378–384Google Scholar
  20. Badinga L, Thatcher WW, Diaz T, Drost M, Wolfenson D (1993) Effect of environmental heat stress on follicular development and steroidogenesis in lactating Holstein cows. Theriogenology 39:797–810Google Scholar
  21. Badinga L, Thatcher WW, Wilcox CJ, Morris G, Entwistle K, Wolfenson D (1994) Effect of season on follicular dynamics and plasma concentrations of estradiol-17ß, progesterone and luteinizing hormone in lactating Holstein cows. Theriogenology 42:1263–1274Google Scholar
  22. Barr VA, Malide D, Zarnowski MJ, Taylor SI, Cushman SW (1997) Insulin stimulates both leptin secretion and production by rat white adipose tissue. Endocrinology 138:4463–4472Google Scholar
  23. Bauman DE, Currie WB (1980) Partitioning of nutrients during pregnancy and lactation. A review of mechanisms involving homeostasis and homeorhesis. J Dairy Sci 63:1514–1545Google Scholar
  24. Beam SW, Butler WR (1999) Effects of energy balance on follicular development and first ovulation in postpartum dairy cows. J Reprod Fertil 54:411–424Google Scholar
  25. Beede DK, Collier RJ (1986) Potential nutritional strategies for intensively managed cattle during thermal stress. J Anim Sci 62:543–554Google Scholar
  26. Beraidinell LJG, Godfrey RW, Adair R, Lunstra DD, Byerley DJ, Gardenas H, Randel RD (1992) Cortisol and prolactin concentrations during different seasons in relocated Brahma and Hereford bulls. Theriogenology 37:641–654Google Scholar
  27. Bernabucci U, Lacetera N, Basirico L, Ronchi B, Morera P, Seren E, Nardone A (2006) Hot season and BCS affect leptin secretion of periparturient dairy cows. J Dairy Sci 89:348–349Google Scholar
  28. Bernabucci U, Basirico L, Morera P, Lacetera N, Ronchi B, Nardone A (2009) Heat shock modulates adipokines expression in 3T3-L1 adipocytes. J Mol Endocrinol 42:139–147Google Scholar
  29. Bernabucci U, Lacetera N, Baumgard LH, Rhoads RP, Ronchi B, Nardone A (2010) Metabolic and hormonal acclimation to heat stress in domesticated ruminants. Animal 4:1167–1183 & The Animal Consortium, doi: 10.1017/S175173111000090X Google Scholar
  30. Billing H, Furuta I, Hsueh AJW (1993) Estrogens inhibit and androgens enhance ovarian granulosa cell apoptosis. Endocrinology 133:2204–2212Google Scholar
  31. Block SS, Butler WR, Ehrhardt RA, Bell AW, Van Amburgh ME, Boisclair YR (2001) Decreased concentration of plasma leptin in periparturient dairy cows is caused by negative energy balance. J Endocrinol 171:339–348Google Scholar
  32. Block SS, Smith JM, Ehrhardt RA, Diaz MC, Rhoads RP, Van Amburgh ME, Boisclair YR (2003) Nutritional and developmental regulation of plasma leptin in dairy cattle. J Dairy Sci 86:3206–3214Google Scholar
  33. Bocquier F, Bonnet M, Faulconnier Y, Guerre-Millo M, Martin P, Chilliard Y (1998) Effects of photoperiod and feeding level on adipose tissue metabolic activity and leptin synthesis in the ovariectomized ewe. Reprod Nutr Dev 38:489–498Google Scholar
  34. Bodensteiner KJ, Wiltbanl MC, Bergfelt DR, Ginther OJ (1995) Alternations in follicular estradiol and gonadotropin receptors during development of bovine antral follicles. Theriogenology 44:499–512Google Scholar
  35. Bousquet D, Bouchard E, DuTremblay D (2004) Decreasing fertility in dairy cows: myth or reality? In: Proceedings 23rd World Buiatrics Congress, Que’bec, 11–16 JulyGoogle Scholar
  36. Breuel KF, Spitzer JC, Thompson CE, Breuel J (1990) First-service pregnancy rate in beef heifers as influenced by human chorionic gonadotrophin administration before and/or after breeding. Theriogenology 34:139–145Google Scholar
  37. Butler WR, Smith RD (1989) Interrelationship between energy balance on postpartum reproductive function in dairy cattle. J Dairy Sci 7:767–783Google Scholar
  38. Butler WR, Calaman JJ, Beam SW (1996) Plasma and milk urea nitrogen in relation to pregnancy rate in lactating dairy cattle. J Anim Sci 74:858–865Google Scholar
  39. Camp TA, Rahal JO, Mayo KE (1991) Cellular localization and hormonal regulation of follicle-stimulating hormone and luteinizing hormone receptor messenger RNAs in the rat ovary. Mol Endocrinol 5:1405–1417Google Scholar
  40. Carlson JR (1969) Growth regulators. In: Hafez ESE, Dyer IA (eds) Animal growth and nutrition. Lea and Febiger, Philadelphia, pp 138–155Google Scholar
  41. Chaiyabuter N, Buranakarl C, Muangcharoen V, Loypetjra P, Pichaicharnarong A (1987) Effects of acute heat stress on changes in the rate of liquid flow from the rumen and turnover of body water of swamp buffalo (Bubalus bubalis). J Agric Sci (Camb) 108:549–553Google Scholar
  42. Chaiyabutr N, Chanpongsang S, Suadsong S (2008) Effects of evaporative cooling on the regulation of body water and milk production in crossbred Holstein cattle in a tropical environment. Int J Biometeorol 52:575–585. doi: 10.1007/s00484-008-0151-x Google Scholar
  43. Chowers I, Hammel HT, Eisenman J, Abrams RM, McCann SM (1966) Comparison of effect of environmental and preoptic heating and pyrogen on plasma cortisol. Am J Physiol 210:606Google Scholar
  44. Christison GI, Johnson HD (1972) Cortisol turnover in heat stressed cows. J Anim Sci 35:1005–1010Google Scholar
  45. Chun SY, Eisenhauer KM, Minami S, Billig H, Perlas E, Hsueh AJ (1996) Hormonal regulation of apoptosis in early antral follicles: follicle-stimulating hormone as a major survival factor. Endocrinology 137:1447–1456Google Scholar
  46. Cohick WS, Clemmons DR (1993) The insulin like growth factor. Annu Rev Physiol 55:131–153Google Scholar
  47. Collier RJ, Beede DK, Thatcher WW, Israel LA, Wilcox CJ (1982a) Influences of environment and its modification on dairy animal health and production. J Dairy Sci 65:2213–2227Google Scholar
  48. Collier RJ, Doelger SG, Head HH, Thatcher WW, Wilcox CJ (1982b) Effects of heat stress on maternal hormone concentrations, calf birth weight, and postpartum milk yield of Holstein cows. J Anim Sci 54:309–319Google Scholar
  49. Collier RJ, Dahl GE, VanBaale MJ (2006a) Major advances associated with environmental effects on dairy cattle. J Dairy Sci 89:1244–1253Google Scholar
  50. Collier RJ, Stiening CM, Pollard BC, VanBaale MJ, Baumgard LH, Gentry PC, Coussens PM (2006b) Use of gene expression microarrays for evaluating environmental stress tolerance at the cellular level in cattle. J Anim Sci 84:1–13Google Scholar
  51. Cunningham JG, Klein BG (2007) Veterinary physiology, 4th edn. Saunders Elsevier, MissouriGoogle Scholar
  52. Darwash AO, Lamming GE, Woolliams JA (1999) The potential for identifying heritable endocrine parameters associated with fertility in post-partum dairy cows. Anim Reprod Sci 68:333–347Google Scholar
  53. De Rensis F, Scaramuzzi RJ (2003) Heat stress and seasonal effects on reproduction in dairy cow-a review. Theriogenology 60:1139–1151Google Scholar
  54. Diskin MG, Stagg K, Mackey DR, Roche JF, Sreenan JM (1999) Nutrition and oestrus and ovarian cycles in cattle, http://www.teagasc.ie/research/reports/beef/4009/eopr-4009.pdf. ISBN No. 1841700894
  55. Dobson H, Ghuman S, Prabhakar S, Smith R (2003) A conceptual model of the influence of stress on female reproduction. Reproduction 125:151–163Google Scholar
  56. Dorrington JH, Moon YS, Armstrong DT (1975) Estradiol-17b biosynthesis in cultured granulosa cells from hypophysectomized immature rats: stimulation by follicle-stimulating hormone. Endocrinology 97:1328–1331Google Scholar
  57. Dunkel L, Tilly JL, Shikone T, Nishimori S, Hsueh AJW (1994) Follicle-stimulating hormone receptor expression in the rat ovary: increases during prepubertal development and regulation by the opposing actions of transforming growth factors b and a. Biol Reprod 50:940–948Google Scholar
  58. Dwaraknath PIC, Agarwal SP, Agarwal VK, Dixit NIC, Sharma IJ (1984) Hormonal profiles in buffalo bulls. In: The use of nuclear techniques to improve domestic buffalo production in Asia, Proceedings of isotope & radiation applications of agricultural development, ManilaGoogle Scholar
  59. Ebling FJP, Wood RI, Karsch FJ, Vannerson LA, Suttie JM, Bucholtz DC, Scball RE, Foster DL (1990) Metabolic interfaces between growth and reproduction. 111. Central mechanisms controlling pulsatile luteinizing hormone secretion in the nutritionally growth-limited female lamb. Endocrinology 126:2719–2727Google Scholar
  60. Edwards RI, Omtvedt IT, Turman EJ, Stephens DE, Mahoney GWA (1968) Reproductive performance of gilts following heat stress prior to breeding and in early lactation. J Anim Sci 27:1634Google Scholar
  61. Elenkov IJ, Chrousos GP (1999) Stress hormones, Th1/Th2 patterns, pro/anti-inflammatory cytokines and susceptibility to disease. Trends Endrocr Metab 10:359–368Google Scholar
  62. El-Mastry KA, Habeeb AA (1989) Thyroid function in lactating Friesian cows and water buffaloes in winter and summer Egyptian conditions. In: 3rd Egyptian – British conference on animal, fish and poultry production, Alexandria University, Cairo, pp 613–620Google Scholar
  63. El-Nouty FD, Hassan GA (1983) Thyroid hormone status and water metabolism in Hereford cows exposed to high ambient temperature and water deprivation. Indian J Anim Sci 53:807–812Google Scholar
  64. El-Nouty FD, El-Banna IM, Daandon IP, Johnson HD (1980) Aldosterone and ADH response to heat and dehydration in cattle. J Appl Physiol 48:249–255Google Scholar
  65. Elvinger F, Natzke RP, Hansen PJ (1992) Interactions of heat stress and bovine somatotropin affecting physio­logy and immunology of lactating cows. J Dairy Sci 75:449–462Google Scholar
  66. Engler D, Pham T, Fullerton MJ, Ooi G, Funder JW, Clarke IJ (1989) Studies of the secretion of corticotrophin-releasing factor and arginine vasopressin into the hypophysial-portal circulation of the conscious sheep. Neuroendocrinology 49:367–381Google Scholar
  67. Erickson GF, Hsueh AJW (1978) Stimulation of aromatase activity by follicle-stimulating hormone in rat granulosa cells in vivo and in vitro. Endocrinology 102:1275–1282Google Scholar
  68. Fajardo LF, Prionas SD, Kowalski J, Kwan HH (1988) Hyperthermia inhibits angiogenesis. Radiat Res 114:297–306Google Scholar
  69. Fantuzzi G (2005) Adipose tissue, adipokines and inflammation. J Allergy Clin Immunol 115:911–919Google Scholar
  70. Findlay JK (1993) An update on the role of inhibin, activin, and follistatin as local regulators of folliculogenesis. Biol Reprod 48:15–23Google Scholar
  71. Fortune JE (1994) Ovarian follicular growth and development in mammals. Biol Reprod 50:225–232Google Scholar
  72. Foster DL, Ebling FJP, Micka AF, Vannerson LA, Bucholtz DC, Wood RI, Suttie JM, Fenner DE (1989) Metabolic interfaces between growth and reproduction. I. Nutritional modulation of gonadotropin, prolactin and growth hormone secretion in the growth-limited female lamb. Endocrinology 125:342–350Google Scholar
  73. Franchimont D, Louis E, Dewe W, Martens H, Vrindts-Gevaert Y, de Groote D, Belaiche J, Greenen V (1998) Effects of dexamethasone on the profile of cytokine secretion in human whole blood cell cultures. Regul Pept 73:59–65Google Scholar
  74. Friedman JM (2002) The function of leptin in nutrition, weight and physiology. Nutr Rev 60:1–14Google Scholar
  75. Gale CC (1973) Neuroendocrine aspects of thermoregulation. Annu Rev Physiol 35:391Google Scholar
  76. Gangwar PC, Branton C, Evans DL (1965) Reproductive and physiological response of Holstein heifers to controlled and natural climatic conditions. J Dairy Sci 48:222–227Google Scholar
  77. Gauthier D (1986) The influence of season and shade on oestrous behaviour, timing of preovulatory LH surge and the pattern of progesterone secretion in FFPN and Creole heifers in a tropical climate. Reprod Nutr Dev 26:767–775Google Scholar
  78. Gilad E, Meidan R, Berman A, Graber Y, Wolfenson D (1993) Effect of heat stress on tonic and GnRH-induced gonadotropin secretion in relation to concentration of estradiol in plasma of cyclic cows. J Reprod Fertil 99:315–321Google Scholar
  79. Goldstein BJ, Scalia R (2004) Adiponectin: a novel adipokine linking adipocytes and vascular function. J Clin Endocrinol Metabol 89:2563–2568Google Scholar
  80. Gwazdauskas FC, Thatcher WW, Kiddy CA, Paper MJ, Wilcox CJ (1981) Hormonal pattern during heat stress following PGF2alpha-tham salt induced luteal regression in heifers. Theriogenology 16:271–285Google Scholar
  81. Habeeb AAM (1987) The role of insulin in improving productivity of heat stressed farm animals with different techniques. PhD thesis, Faculty of Agriculture, Zagazig University, ZagazigGoogle Scholar
  82. Habeeb AAM, Ibrahim MKH, Yousef HM (2000) Blood and milk contents of triiodothyronine (T3) and cortisol in lactating buffaloes and changes in milk yield and composition as a function of lactation number and ambient temperature. Arab J Nucl Sci Appl 33:313–322Google Scholar
  83. Habeeb AAM, Aboulnaga AJ, Kamal TH (2001) Heat-induced changes in body water concentration, Ts, cortisol, glucose and cholesterol levels and their relationships with thermoneutral bodyweight gain in Friesian calves. In: Proceedings of 2nd international conference on animal production and health in semi-arid areas, El-Arish, North Sinai, pp 97–108Google Scholar
  84. Habeeb AAM, Fatma FIT, Osman SF (2007) Detection of heat adaptability using heat shock proteins and some hormones in Egyptian buffalo calves. Egypt J Appl Sci 22:28–53Google Scholar
  85. Hall JE, Crook ED, Jones DW, Wofford MR, Dubbert PM (2002) Mechanisms of obesity-associated cardiovascular and renal disease. Am J Med Sci 324:127–137Google Scholar
  86. Hamilton TD, Vizcarra JA, Wettermann RP, Keefer BE, Spicer LJ (1999) Ovarian function in nutritionally induced anoestrus cows: effect of exogenous gonadotrophin-releasing hormone in vivo and effect of insulin and insulin-like growth factor I in vitro. J Reprod Fertil 117:179–187Google Scholar
  87. Havel PJ (2002) Control of energy homeostasis and insulin action by adipocyte hormones: leptin, acylation stimulating protein, and adiponectin. Curr Opin Lipidol 13:51–59Google Scholar
  88. Havel PJ (2004) Update on adipocytes hormones. Regulation of energy balance and carbohydrate/lipid metabolism. Diabetes 53:143–151Google Scholar
  89. Hein KG, Allrich RD (1992) Influence of exogenous adrenocorticotropic hormone on estrous behavior in cattle. J Anim Sci 70:243–247Google Scholar
  90. Horowitz M (2001) Heat acclimation: phenotypic plasticity and cues to the underlying molecular mechanism. J Therm Biol 26:357–363Google Scholar
  91. Houseknecht KL, Baile CA, Matteri RL, Spurlock ME (1998) The biology of leptin: a review. J Anim Sci 76:1405–1420Google Scholar
  92. Howell JL, Fuquay JW, Smith AE (1994) Corpus luteum growth and function in lactating Holstein cows during spring and summer. J Dairy Sci 77:735–739Google Scholar
  93. Hsueh AJW, Billig H, Tsafriri A (1994) Ovarian follicle atresia: a hormonally controlled apoptotic process. Endocr Rev 15:707–724Google Scholar
  94. Igono MO, Johnson HD, Steevens BJ, Krause GF, Shanklin MD (1987) Physiological, productive, and economic benefits of shade, spray, and fan system versus shade for Holstein cows during summer heat. J Dairy Sci 70:1069–1079Google Scholar
  95. Igono MO, Johnson HD, Steevens BJ, Hainen WA, Shanklin MD (1988) Effect of season on milk temperature, milk growth hormone, prolactin, and somatic cell counts of lactating cattle. Int J Biometeorol 32:194–200Google Scholar
  96. Ingraham RH, Gillette DD, Wagner WD (1974) Relationship of temperature and humidity to conception of Holstein cows in tropical climate. J Dairy Sci 54:476–481Google Scholar
  97. Ingraham RH, Kappel LC, Morgan EB, Babcock DK (1982) Temperature-humidity vs seasonal effects on concentrations of blood constituents of dairy cows during the pre and post-calving periods: relationship to lactation level and reproductive functions. In: Proceedings of 2nd international livestock and environment symposium, American Society of Agricultural Engineers, St. Joseph, pp 565–570Google Scholar
  98. Johnson HD, Van Jonack WJ (1976) Effects of environmental and other stressors on blood hormone patterns in lactating animals. J Dairy Sci 59:1603–1617Google Scholar
  99. Johnson HD, Katti PS, Hahn L, Shanklin MD (1988) Short-term heat acclimation effects on hormonal profile of lactating cows. University of Missouri Research Bulletin no 1061, ColumbiaGoogle Scholar
  100. Johnson HD, Shanklin MD, Hahn L (1989) Productive adaptability indices of Holstein cattle to environmental heat. In: Agriculture and forest and meteorology conference, pp 291–297, Boston, USA; American Meteorological SocietyGoogle Scholar
  101. Johnson HD, Li R, Manalu W, Spencer-Johnson KJ (1991) Effects of somatotropin on milk yield and physiological responses during summer farm and hot laboratory conditions. J Dairy Sci 74:1250–1262Google Scholar
  102. Jonsson NN, McGowan MR, Mcguigan K, Davison TM, Hussian AM, Kafi M, Matschoss A (1997) Relationships among calving season, heat load, energy balance and postpartum ovulation of dairy cows in a subtropical environment. Anim Reprod Sci 47:315–326Google Scholar
  103. Juniewicz PE, Johnson BH, Bolt DJ (1987) Effect of adrenal steroids on testosterone and luteinizing hormone secretion in the ram. J Androl 8:190–196Google Scholar
  104. Kamal TH, Ibrahim II (1969) The effect of the natural climate of the Sahara and controlled climate on thyroid gland activity in Friesian cattle and water buffaloes. Int J Biometeorol 13:287–294Google Scholar
  105. Kamal TH, Habeeb AA, Abdel-Samee AM, Abdel-Razik MA (1989) Supplementation of heat-stressed Friesian cows with urea and mineral mixture and its effect on milk production in the subtropics. In: Proceedings of symposium on ruminant production in the dry subtropics: constraints and potentials, Cairo. EAAP Publication no. 38, Pudoc Science Publication, Wageningen, pp 183–185Google Scholar
  106. Kamigaki M, Sakaue S, Tsujino I, Ohira H, Ikeda D, Itoh N, Ishimaru S, Ohtsuka Y, Nishimura M (2006) Oxidative stress provokes atherogenic changes in adipokine gene expression in 3T3-L1 adipocytes. Biochem Biophys Res Commun 339:624–632Google Scholar
  107. Kaneko H, Nakanishi Y, Akagi S, Arai K, Watanabe G, Sasamoto S, Hasegawa S (1995) Immunoneutralization of inhibin and estradiol during the follicular phase of the estrus cycle in cows. Biol Reprod 53:931–939Google Scholar
  108. Kaneko H, Taya K, Watanabe G, Noguchi J, Kikuchi K, Shimada A, Hasegawa S (1997) Inhibin is involved in suppression of FSH secretion in the growth phase of the dominant follicle during the early luteal phase in cows. Domest Anim Endocrinol 14:263–271Google Scholar
  109. Kaufman FL, Mills DE, Hughson RL, Peake GT (1988) Effects of bromocriptine on sweat gland function during heat acclimatization. Horm Res 29:31–38Google Scholar
  110. Khodaei MM (2003) Study of some effective factors in reproductive performance of Iranian Holstein Cows. Thesis, Animal Physiology, Tehran University, TehranGoogle Scholar
  111. Khodaei M, Roohani MZ, Zare A, Moradi Share Babak M (2006) Study of some effective factors in reproductive performance in sharif abad Ghazvin company and Shir-o-dame Boniad. In: Proceedings of 2nd congress animal science, TehranGoogle Scholar
  112. Kim JM, Boone DL, Auyeung A, Tsang BK (1998) Granulosa cell apoptosis induced at penultimate stage of follicular development is associated with increased levels of Fas and Fas ligand in the rat ovary. Biol Reprod 58:1170–1176Google Scholar
  113. Kok FW, Heijnen CJ, Bruijn JA, Westenberg HGM, Van Ree JM (1995) Immunoglobulin production in vitro in major depression: a pilot study on the modulating action of endogenous cortisol. Biol Psychiatry 38:217–226Google Scholar
  114. Lacetera N, Bernabucci U, Basirico L, Morera P, Nardone A (2009) Heat shock impairs DNA synthesis and down-regulates gene expression for leptin and Ob-Rb receptor in concanavalin A-stimulated bovine peripheral blood mononuclear cells. Vet Immunol Immunopathol 127:190–194Google Scholar
  115. Lafontan M, Viguerie N (2006) Role of adipokines in the control of energy metabolism: focus on adiponectin. Curr Opin Pharmacol 6:1–6Google Scholar
  116. Lamming GE, Royal MD (2001) Ovarian hormone patterns and subfertility in dairy cows. In: Diskin MG (ed) Fertility in the high producing dairy cow, BSAS Edinburgh: Occasional Publication 26, pp 105–118Google Scholar
  117. Lamming GE, Darwash A, Black HL (1989) Corpus luteum function in dairy cows and embryo mortality. J Reprod Fertil 37:245–252Google Scholar
  118. LaPolt PS, Tilly JL, Aihara T, Nishimori K, Hsueh AJ (1992) Gonadotropin-induced up- and down-regulation of ovarian follicle-stimulating hormone (FSH) receptor gene expression in immature rats: effects of pregnant mare’s serum gonadotropin, human chorionic gonadotropin, and recombinant FSH. Endocrinology 130:1289–1295Google Scholar
  119. Leining KB, Bourne RA, Tucker HA (1979) Prolactin response to duration and wavelength of light in prepubertal bulls. Endocrinology 104:289–294Google Scholar
  120. Leining DB, Tucker HA, Kesner JS (1980) Growth hormone, glucocorticoids and thyroxine response to duration, intensity and wave length of light in pre-pubertal bulls. J Anim Sci 51:932–942Google Scholar
  121. Lindner HR (1964) Comparative aspects of cortisol transport. Lack of firm binding to plasma proteins in domestic ruminants. J Endocrinol 28:301Google Scholar
  122. Linquist S (1986) The heat–shock response. Annu Rev Biochem 55:1151–1191Google Scholar
  123. Lippsett MB, Schwartz TL, Thon NA (1961) Hormonal control of sodium, potassium, chloride and water metabolism. In: Comar CL, Bonner F (eds) Mineral metabolism, lBth edn. Academic, New YorkGoogle Scholar
  124. Lublin A, Wolfenson D (1996) Effect of blood flow to mammary and reproductive systems in heat-stressed rabbits. Comp Biochem Physiol 115:277–285. Sinauer Associates, MAGoogle Scholar
  125. MacMurray JP, Barker JP, Armstrong JD, Bozzetti LP, Kuhn IN (1983) Circannual changes in immune function. Life Sci 32:2363–2370Google Scholar
  126. Madan ML, Johnson HD (1973) Environmental heat effects on bovine luteinizing hormone. J Dairy Sci 56:1420–1423Google Scholar
  127. Magdub A, Johnson HD, Belvea RL (1982) Effect of environmental heat and dietary fiber on thyroid physiology of lactating cows. J Dairy Sci 65:2323Google Scholar
  128. Malayer JR, Hansen PJ (1990) Differences between Brahman and Holstein cows in heat-shock induced alterations of protein secretion by oviducts and uterine endometrium. J Anim Sci 68:266–280Google Scholar
  129. Mann GE, Lamming GE (2001) Relationship between maternal endocrine environment, early embryo development and inhibition of leutolytic mechanism in cows. Reproduction 121:175–180Google Scholar
  130. Mann GE, Lamming GE, Fray MD (1995) Plasma estradiol and progesterone during early pregnancy in the cow and the effects of treatment with buserelin. Anim Reprod Sci 37:121–131Google Scholar
  131. Mann GE, Lamming GE, Robinson RS, Wathes DC (1999) The regulation of interferon-tau production and uterine hormone receptors during early pregnancy. J Reprod Fertil 54:317–328Google Scholar
  132. Mann GE, Merson P, Fray MD, Lamming GE (2001) Conception rate following progesterone supplementation after second insemination in dairy cows. Vet J 162:161–162Google Scholar
  133. McEwen BS, Goodman HM (eds) (2001) Handbook of physiology; section 7: The endocrine system, vol IV: Coping with the environment: neural and endocrine mechanisms. Oxford University Press, New YorkGoogle Scholar
  134. McGuire MA, Beede DK, DeLorenzo MA, Wilcox CJ, Huntington GB, Reynolds CK, Collier RJ (1989) Effects of thermal stress and level of feed intake on portal plasma flow and net fluxes of metabolites in lactating Holstein cows. J Anim Sci 67:1050–1060Google Scholar
  135. McGuire MA, Beede DK, Collier RJ, Buonomo FC, Delorenzo MA, Wilcox CJ, Huntington GB, Reynolds CK (1991) Effect of acute thermal stress and amount of feed intake on concentrations of somatotropin, insulin-like growth factor I (IGF-I) and IGF-II and thyroid hormones in plasma of lactating dairy cows. J Anim Sci 69:2050–2056Google Scholar
  136. McNatty KP, Heath DA, Henderson KM, Lun S, Hurst PR, Ellis LM, WMntgomery G, Morrison L, Hurly DC (1984) Some aspects of thecal and granulosa cell function during follicular development in the bovine ovary. J Reprod Fertil 72:39–53Google Scholar
  137. McVeign JM, Tarrent PV (1982) Behavioral stress and skeletal muscle glycogen metabolism in young bulls. J Anim Sci 54:790Google Scholar
  138. Mitra R, Christison GI, Johnson HD (1972) Effect of prolonged thermal exposure on growth hormone (GH) secretion in cattle. J Anim Sci 34:776–779Google Scholar
  139. Moseley PL (1998) Heat shock proteins and the inflam­matory response. Ann N Y Acad Sci 856:206–213Google Scholar
  140. Moynihan JA (2003) Mechanisms of stress-induced modulation of immunity. Brain Behav Immun 17:11–16Google Scholar
  141. Nakamura K, Minegishi T, Takakura Y, Miyamoto K, Hasegawa Y, Ibuki Y, Igarashi M (1991) Hormonal regulation of gonadotropin receptor mRNA in rat ovary during follicular growth and luteinization. Mol Cell Endocrinol 82:259–263Google Scholar
  142. Nakamura H, Seto T, Nagase H, Yoshida M, Dan S, Ogino K (1997) Inhibitory effect of pregnancy on stress-induced immunosuppression through corticotropin releasing hormone (CRH) and dopaminergic systems. J Neuroimmunol 75:1–8Google Scholar
  143. Nardone A, Lacetera NG, Bernabucci U, Ronchi B (1997) Composition of colostrum from dairy heifers exposed to high air temperatures during late pregnancy and early postpartum period. J Dairy Sci 80:838–844Google Scholar
  144. Nelson RJ (2005) An introduction to behavioral endocrinology, 3rd edn. Sinauer Associates, SunderlandGoogle Scholar
  145. Nessim MG (2004) Heat-induced biological changes as heat tolerance indices related to growth performance in buffaloes. PhD thesis, Faculty of Agriculture, Ain Shams University, CairoGoogle Scholar
  146. Niles MA, Collier RJ, Croom WJ (1980) Effect of heat stress on rumen and plasma metabolite and plasma hormone concentration of Holstein cows. J Anim Sci (Suppl) 152 (Abstract)Google Scholar
  147. Norman AW, Litwack G (1987) Hormones. Academic, New York, pp 408–415Google Scholar
  148. Norris DO (2007) Vertebrate endocrinology, 4th edn. Academic, BostonGoogle Scholar
  149. Oltvai ZN, Milliman CL, Korsmeyer SJ (1993) Bcl-2 heterodimerizes in vivo with a conserved homolog, Bax, that accelerates programmed cell death. Cell 74:609–619Google Scholar
  150. Overton TR, Waldron MR (2004) Nutritional management of transition dairy cows: strategies to optimize metabolic health. J Dairy Sci 87(13 suppl):105–199Google Scholar
  151. Palta P, Mondal S, Prakas BS, Madan ML (1997) Peripheral inhibin levels in relation to climatic variations and stage of estrous cycle in buffalo (Bubalus bubalis). Theriogenology 47:898–995Google Scholar
  152. Palumbo A, Yeh J (1994) In situ localization of apoptosis in the rat ovary during follicular atresia. Biol Reprod 51:888–895Google Scholar
  153. Parr RA, Davis IF, Miles MA, Squires TJ (1993) Liver blood flow and metabolic clearance rate of progesterone in sheep. Res Vet Sci 55:311–316Google Scholar
  154. Perera KS, Gwazdauskas FC, Akers RM, Pearson RE (1985) Seasonal and lactational effects on response to thyrotropin releasing hormone injection in Holstein cows. Domest Anim Endocrinol 2:43–52Google Scholar
  155. Perez JH, Fernandez O (1988) Thyroid hormone levels in heat tolerant and non-tolerant Friesian heifers. Revista de Salud Anim 10:121–130Google Scholar
  156. Perez H, Mendoza E, Alvarez JL, Fernandez O (1997) Effect of the temperature humidity index on secretion of thyroid hormones in Holstein heifers. Revista de Salud Anim 19(2):131–135Google Scholar
  157. Pittas AG, Joseph NA, Greenberg AS (2004) Adipocytokines and insulin resistance. J Clin Endocrinol Metabol 89:447–452Google Scholar
  158. Plasse D, Warnick AC, Koger J (1970) Reproductive behavior of Bos indicus females in a subtropical environment. IV. Length of estrous cycle, duration of estrus, time of ovulation, fertilization and embryo survival in grade Brahman heifers. J Anim Sci 30:63Google Scholar
  159. Pusta D, Odagiu A, Ersek A, Pascal I (2003) The variation of triiodothyronine (T3) level in milking cows exposed to direct solar radiation. J Cent Euro Agric 4:308–312Google Scholar
  160. Putney DJ, Malayer JR, Gross TS, Thatcher WW, Hansen PJ, Drost M (1988) Heat-stress induced alterations in the synthesis and secretion of proteins and prostaglandins by cultured bovine conceptuses and uterine endometrium. Biol Reprod 39:717–728Google Scholar
  161. Ray DE, Halbach TJ, Armstrong DV (1992) Season and lactation number effects on milk production and reproduction in dairy cattle in Arizona. J Dairy Sci 75:2976–2983Google Scholar
  162. Richards JI (1985) Effect of high daytime temperature on the intake and utilization of water in lactating Friesian cows. Trop Anim Health Prod 17:209–217Google Scholar
  163. Robinson NA, Leslie KE, Walton JS (1989) Effect of treatment with progesterone on pregnancy rate and plasma concentrations of progesterone in Holstein cows. J Dairy Sci 72:202–207Google Scholar
  164. Roche JR, Kolver ES, Kay JK (2005) Influence of precalving feed allowance on periparturient metabolic and hormonal responses and milk production in grazing dairy cows. J Dairy Sci 88:677–689Google Scholar
  165. Roman-Ponce H, Thatcher WW, Wilcox CJ (1981) Hormonal interrelationships and physiological responses of lactating dairy cows to a shade management system in a subtropical environment. Theriogenology 16:139–154Google Scholar
  166. Romero LM (2004) Physiological stress in ecology: lessons from biomedical research. Trends Ecol Evol 19:249–255Google Scholar
  167. Ronchi B, Bernabucci U, Lacetera N, Verini Supplizi A, Nardone A (1999) Distinct and common effects of heat stress and restricted feeding on metabolic status of Holstein heifers. Zootecnica e Nutrizione Animale 25:11–20Google Scholar
  168. Ronchi B, Stradaioli G, Verini Supplizi A, Bernabucci U, Lacetera N, Accorsi PA, Nardone A, Seren E (2001) Influence of heat stress or feed restriction on plasma progesterone, oestradiol–17b, LH, FSH, prolactin and cortisol in Holstein heifers. Livest Prod Sci 68:231–241Google Scholar
  169. Rosenberg M, Folman Y, Herz Z, Flamenbaum I, Berman A, Kaim M (1982) Effect of climatic conditions on peri0pheral concentrations of LH, progesterone and oestradiol-17b in high milk-yielding cows. J Reprod Fertil 66:13–146Google Scholar
  170. Roth Z, Arav A, Bor A, Zeron Y, Ocheretny A, Wolfenson D (1999) Enhanced removal of impaired follicles improves the quality of oocytes collected in the autumn from summer heat-stressed cows. J Reprod Fertil Abstr Ser 23:78 (Abstract)Google Scholar
  171. Roth Z, Meidan R, Braw-Tal R, Wolfenson D (2000) Immediate and delayed effect of heat stress on follicular development and its association with plasma FSH and inhibin concentration in cows. J Reprod Fertil 120:83–90Google Scholar
  172. Roth Z, Meidan R, Shaham-Albalancy A, Braw-Tal R, Wolfenson D (2001) Delayed effect of heat stress on steroid production in medium-sized and preovulatory bovine follicles. Anim Reprod Sci 121:745–751Google Scholar
  173. Roy KS, Prakash BS (2007) Seasonal variation and circadian rhythmicity of the prolactin profile during the summer months in repeat-breeding Murrah buffalo heifers. Reprod Fertil Dev 19:569–575Google Scholar
  174. Sangsritavong S, Combs DK, Satori R, Armentano LE, Wiltbank MC (2002) High feed intake increase liver blood flow and metabolism of progesterone and estradiol 17 beta in dairy cattle. J Dairy Sci 85:2831–2842Google Scholar
  175. Santos JEP, Thatcher WW, Chebela RC, Cerria RLA, Galvãoa KN (2004) The effect of embryonic death rates in cattle on the efficacy of estrus synchronization programs. Anim Reprod Sci 82–83:513–535Google Scholar
  176. Sapolsky RM, Romero LM, Munck AU (2000) How do glucocorticoids influence stress-responses? Integrating permissive, suppressive, stimulatory, and adaptive actions. Endocr Rev 21:55–89Google Scholar
  177. Scott IM, Johnson HD, Hahn GL (1983) Effect of programmed diurnal temperature cycles on plasma thyroxine level, body temperature, and feed intake of Holstein dairy cows. Int J Biometeorol 27:47–62Google Scholar
  178. Sejrsen K, Fitzgerald EM, Tucker HA, Huber JT (1980) Effect of plane of nutrition on serum prolactin and insulin in pre-and post-pubertal heifers. J Dairy Sci 53(suppl 1):326–327, AbstractGoogle Scholar
  179. Shimizu T, Ohshima I, Kanai Y (2000) Effect of heat stress on follicular development in PMSG-treated immature rats. Anim Sci J 71:32–37Google Scholar
  180. Shimizu T, Izumi O, Manabu O, Satoko T, Atsushi T, Masayuki S, Hitoshi M, Yukio K (2005) Heat stress diminishes gonadotropin receptor expression and enhances susceptibility to apoptosis of rat granulosa cells. Reproduction 129:463–472Google Scholar
  181. Silanikove N (2000) Effects of heat stress on the welfare of extensively managed domestic ruminants. Livest Prod Sci 67:1–18Google Scholar
  182. Spicer LJ, Tucker WB, Adams GD (1990) Insulin-like growth factor-I in dairy cows: relationships among energy balance, body condition, ovarian activity, and estrous behavior. J Dairy Sci 13:929–931Google Scholar
  183. Stott GH (1972) Climatic thermal stress. A cause of hormone depression and low fertility in bovine. Biometeorogy 5:113 (Abstract)Google Scholar
  184. Stott GH, Wiersma F (1971) Plasma corticoids as an index of acute and chronic environmental stress. Presented at First conference on biometeorology and tenth conference on agricultural meteorology, ColumbiaGoogle Scholar
  185. Thibier M, Rolland O (1976) The effect of dexamethasone (DXM) on circulating testosterone (T) and luteinizing hormone (LH) in young postpubertal bulls. Theriogenology 5:53–60Google Scholar
  186. Thompson JA, Magee DD, Tomaszewski MA, Wilks DL, Fourdraine RH (1996) Management of summer infertility in Texas Holstein dairy cattle. Theriogenology 46:547–558Google Scholar
  187. Thwaites CJ (1968) The influence of age of ewe on embryo mortality under heat stress conditions. Int J Biometeor 12:29Google Scholar
  188. Tilbrook AJ, Turner AI, Clarke IJ (2000) Effects of heat stress on reproduction in non-rodent mammals: the role of glucocorticoids and sex differences. J Reprod Fertil 5:105–113Google Scholar
  189. Tilly JL (1993) Ovarian follicular atresia: a model to study the mechanisms of physiological cell death. Endocr J 1:67–72Google Scholar
  190. Tilly JL (1996) Apoptosis and ovarian function. Rev Reprod 1:162–172Google Scholar
  191. Tilly JL, Tilly KI, Kenton ML, Johnson AL (1995) Expression of members of the bcl-2 gene family in the immature rat ovary: equine chorionic gonadotropin-mediated inhibition of granulosa cell apoptosis is associated with decreased bax and constitutive bcl-2 and bcl-xlong messenger ribonucleic acid levels. Endocrinology 136:232–241Google Scholar
  192. Trayhurn P (2005) Endocrine and signalling role of adipose tissue: new perspectives on fat. Acta Physiol Scand 184:285–293Google Scholar
  193. Trout JP, Mcdowell LR, Hansen PJ (1998) Characteristics of the estrus cycle and antioxidant status of lactating Holstein cows exposed to stress. J Dairy Sci 81:1244–1250Google Scholar
  194. Vasconcelos JLM, Sangsritavong S, Tsai SJ, Wiltbank MC (2003) Acute reduction in serum progesterone concentrations after feed intake in dairy cows. Theriogenology 60:795–807Google Scholar
  195. Wang M, Orci L, Ravazzola M, Unger RH (2005) Fat storage in adipocytes requires inactivation of leptin’s paracrine activity: implication for treatment of human obesity. PNAS 102:18011–18016Google Scholar
  196. Webb R, Garnsworthy PC, Gong JG, Robinson RS, Wathes DC (1999) Consequences for reproductive function of metabolic adaptation to load. British Society of Animal Science, Occasional Publication 24, pp 99–112Google Scholar
  197. Webster JI, Tonelli L, Sternberg EM (2002) Neuroendocrine regulation of immunity. Annu Rev Immunol 20:125–163Google Scholar
  198. Wetteman RP, Tucker HA (1979) Relationship of ambient temperature to serum prolactin in heifers. In: Proceedings of the Society for Experimental Biology and Medicine 146. Academic, New York, pp 909–911Google Scholar
  199. Wilson SJ, Kirby CJ, Koenigsfeld AT, Keisler DH, Lucy MC (1998a) Effects of controlled heat stress on ovarian function of dairy cattle. II. Heifers. J Dairy Sci 81:2132–2138Google Scholar
  200. Wilson SJ, Marion RS, Spain JN, Spiers DE, Keisler DH, Lucy MC (1998b) Effects of controlled heat stress on ovarian function of dairy cattle. I. Lactating cows. J Dairy Sci 81:2124–2131Google Scholar
  201. Wise ME, Armstrong DV, Huber JT, Hunter R, Wiersma F (1988a) Hormonal alteration in the lactating dairy cow in response to thermal stress. J Dairy Sci 71:2480–2485Google Scholar
  202. Wise ME, Rodriguez RE, Armstrong DV, Huber JT, Wiersma F, Hunter R (1988b) Fertility and hormonal response to thermal relief of heat stress in lactating dairy cows. Theriogenology 29:1027–1035Google Scholar
  203. Wolfenson D, Flamenbaum I, Berman A (1988) Hyper­thermia and body energy store effects on oestrus behaviour, conception rate, and corpus luteum function in dairy cows. J Dairy Sci 71:3497–3504Google Scholar
  204. Wolfenson D, Bartol FF, Badinga L, Barros CM, Marple DN, Cummings K, Wolfe D, Lucy MC, Spencer TE, Thatcher WW (1993) Secretion of PGF2a and oxytocin during hyperthermia in cyclic and pregnant heifers. Theriogenology 39:1129–1141Google Scholar
  205. Wolfenson D, Thatcher WW, Badinga L, Savio JD, Meidan R, Lew BJ, Braw-Tai R, Berman R (1995) Effect of heat stress on follicular development during the estrus cycle in lactating dairy cattle. Biol Reprod 52:1106–1113Google Scholar
  206. Wolfenson D, Lew BJ, Thatcher WW, Graber Y, Meidan R (1997) Seasonal and acute heat stress effects on steroid production by dominant follicles in cow. Anim Reprod Sci 47:9–19Google Scholar
  207. Wolfenson D, Roth Z, Meidan R (2000) Impaired reproduction in heat stressed cattle: basic and applied aspects. Anim Reprod Sci 60–61:537–547Google Scholar
  208. Wolfenson D, Sonego H, Bloch A, Shaham-Albalancy A, Kaim M, Folman Y, Meidan R (2002) Seasonal differences in progesterone production by luteinized bovine thecal and granulosa cells. Domest Anim Endocrinol 2:81–90Google Scholar
  209. Yang E, Zha J, Jockel J, Boise LH, Thompson CB, Korsmeyer SJ (1995) Bad, a heterodimeric partner for Bcl-XL and Bcl-2, displaces Bax and promotes cell death. Cell 80:285–291Google Scholar
  210. Younas M, Fuquay JW, Smith AE, Moore AB (1993) Estrus and endocrine responses of lactating Holstein to forced ventilation during summer. J Dairy Sci 76:430–434Google Scholar
  211. Yousef MMM (1992) Growth patterns of calves in relation to rumen development. PhD thesis, Faculty of Agriculture, Cairo University, GizaGoogle Scholar
  212. Yousef MK, Johnson HD (1966a) Blood thyroxine degradation rate in cattle as influenced by temperature and feed intake. Life Sci 5:1349Google Scholar
  213. Yousef MK, Johnson HD (1966b) Calorigenesis of cattle as influenced by growth hormone and environmental temperature. J Anim Sci 25:1076Google Scholar
  214. Yousef JLM, Habeeb AA, EL-Kousey H (1997) Body weight gain and some physiological changes in Friesian calves protected with wood or reinforced concrete sheds during hot summer season of Egypt. Egypt J Anim Prod 34:89–101Google Scholar
  215. Zhengkang H, Zhenzhong C, Shaohua Z, Vale WG, Barnabe VH, Mattos JCA (1994) Rumen metabolism, blood cortisol and T3, T4 levels and other physiological parameters of swamp buffalo subjected to solar radiation. In: Proceedings of world buffalo Congress, San Paulo, vol 2, pp 39–40Google Scholar
  216. Zhou J, Kumar RT, Matzuk MM, Bondy C (1997) Insulin-like growth factor I regulates gonadotropin responsiveness in the murine ovary. Mol Endocrinol 11:1924–1933Google Scholar

Copyright information

© Springer India 2013

Authors and Affiliations

  • Anjali Aggarwal
    • 1
  • Ramesh Upadhyay
    • 1
  1. 1.Dairy Cattle Physiology DivisionNational Dairy Research InstituteKarnalIndia

Personalised recommendations