Cystic ovarian disease in dairy cattle: Aetiology, pathogenesis, and risk factors;Cysteuze ovariële follikels bij melkvee: Etiologie, pathogenese en risicofactoren

Tijdschrift voor Diergeneeskunde

Volumn 127, Issue 5, 2002, Pages 146-155

  Vanholder, T ^a   Opsomer, G ^a   Govaere, J L J ^a   Coryn, M ^a   De Kruif, A ^a  

^a GHENT UNIVERSITY   (Belgium)

Author keywords

[No Author keywords available]

Indexed keywords

ANIMAL; ANIMAL DISEASE; CATTLE; CATTLE DISEASE; FEMALE; HYPOTHALAMUS HYPOPHYSIS SYSTEM; OVARY CYST; OVARY FOLLICLE; OVULATION; PARITY; PATHOLOGY; PATHOPHYSIOLOGY; PHYSIOLOGY; REVIEW; RISK FACTOR; SEASON; STRESS;

ANIMALS; CATTLE; CATTLE DISEASES; FEMALE; HYPOTHALAMO-HYPOPHYSEAL SYSTEM; OVARIAN CYSTS; OVARIAN FOLLICLE; OVULATION; PARITY; RISK FACTORS; SEASONS; STRESS;

EID: 0036518744     PISSN: 00407453     EISSN: None     Source Type: Journal    
DOI: None     Document Type: Article

References (122)

1. Al-Dahash SYA, and David JSE. Anatomical features of cystic ovaries found during an abattoir survey. Vet Rec 1977; 101: 320-4.
2. Austin EJ, Mihm M, Evans ACO, Knight PG, Ireland JLH, Ireland JJ, and Roche JF. Alterations in intrafollicular regulatory factors and apoptosis during selection of follicles in the first follicular wave of the bovine estrous cycle. Biol Reprod 2001; 64: 839-48.
3. Bamberg E, Choi HS, Mostl E, Klaring WJ, und Stockle W. Steroid Hormongehalt und Aromatasenaktivität in Ovarialzysten des Rindes. Mh Vet Med 1981; 28: 366-72.
4. Bartlett PC, Ngategize PK, Kaneene JB, Kirk JH, Anderson SM, and Mather EC. Cystic follicular disease in Michigan Holstein-Friesian cattle: incidence, descriptive epidemiology and economic impact. Prev Vet Med 1986; 4: 15-33.
5. Beg MA, Bergfelt DR, Kot K, Wiltbank MC, and Ginther OJ. Follicular fluid factors and granulosa-cell gene expression associated with follicle deviation in cattle. Biol Reprod 2001; 64: 24-33.
6. Booth JM. The milk progesterone test as an aid to the diagnosis of cystic ovaries in dairy cows. Vet Rec 1988; 123: 437-9.
7. Bosu WTK, and Peter AT. Evidence for a role of intrauterine infections in the pathogenesis of cystic ovaries in postpartum dairy cows. Theriogenology 1987; 28: 725-36.
8. Brown JL, Schoenemann HM, and Reeves JJ. Effect of treatment on LH and FSH receptors in chronic cystic-ovarian diseased dairy cows. J Anim Sci 1986; 62: 1063-71.
9. Butler WR, and Smith RD. Interrelationships between energy balance and postpartum reproductive function in dairy cattle. J Dairy Sci 1989; 72: 767-83.
10. Campbell BK, Scaramuzzi RJ, and Webb R. Induction and maintenance of oestradiol and immunoreactive inhibin production with FSH by ovine granulosa cells cultured in serum-free media. J Reprod Fertil 1996; 106: 7-16.
11. Canfield RW, and Butler WR. Energy balance and pulsatile LH secretion in early postpartum dairy cattle. Dom Anim Endocrinol 1990; 7: 323-30.
12. Cole WJ, Bierschwal CJ, Youngquist RS, and Braun WF. Cystic ovarian disease in a herd of Holstein cows: a hereditary correlation. Theriogenology 1986; 25: 813-20.
13. Cook DL, Parfet JR, Smith CA, Moss GE, Youngquist RS, and Garverick HA. Secretory patterns of LH and FSH during development and hypothalamic and hypophysial characteristics following development of steroid-induced ovarian follicular cysts in dairy cattle. J Reprod Fertil 1991; 91: 19-28.
14. Cook DL, Smith CA, Parfet JR, Youngquist RS, Brown EM, and Garverick HA. Fate and turnover rate of ovarian follicular cysts in dairy cows. J Reprod Fertil 1990; 89: 155-66.
15. Crump AD, and Rodway RG. Hypoglycemia and LH release in the ewe. Proceedings of the Nutr Soc 1986; 45: 100A.
16. Day N. The diagnosis, differentiation, and pathogenesis of cystic ovarian disease. Vet Med 1991; 86: 753-60.
17. Day N. The treatment and prevention of cystic ovarian disease. Vet Med 1991; 86: 761-6.
18. De Silva M, and Reeves JJ. Hypothalamic-pituitary function in chronically cystic and regularly cycling dairy cows. Biol Reprod 1988; 38: 264-9.
19. Dinsmore RP, White ME, Guard CL, Jasko DJ, Perdrizet JA, Powers PM, and Smith MC. Effect of gonadotropin-releasing hormone on clinical response and fertility in cows with cystic ovaries, as related to milk progesterone concentration and days after parturition. J Am Vet Med Assoc 1989; 195: 327-30.
20. Dobson H, Rankin JEF, and Ward WR. Bovine cystic ovarian disease: plasma hormone concentrations and treatment. Vet Rec 1977; 101: 459-61.
21. Dobson H, Campbell BK, Gordon BM, and Scaramuzzi RJ. Endocrine activity of induced persistent follicles in sheep. Biol Reprod 1997; 56: 208-13.
22. Dobson H, and Nanda AS. Reliability of cyst diagnosis and effect of energy status on LH released by estradiol or GnRH in cows with ovarian cysts. Theriogenology 1992; 37: 465-72.
23. Dobson H, Ribadu AY, Noble KM, Tebble JE, and Ward WR. Ultrasonography and hormone profiles of adrenocorticotrophic hormone (ACTH)-induced persistent ovarian follicles (cysts) in cattle. J Reprod Fertil 2000; 120: 405-10.
24. Douthwaite R, and Dobson H. Comparison of different methods of diagnosis of cystic ovarian disease in cattle and an assessment of its treatment with a progesterone-releasing intravaginal device. Vet Rec 2000; 147: 355-9.
25. Dunaif A. Adrenal disorders and Polycystic Ovary Syndrome. Horm Res 1992; 37, suppl 3: 39-44.
26. Edmondson AJ, Fissore RA, Pashen RL, and Bondurant RH. The use of ultrasonography for the study of the bovine reproductive tract 1. Normal and pathological ovarian structures. Anim Reprod Sci 1986; 12: 157-65.
27. Emanuelson U, and Bendixen PH. Occurrence of cystic ovaries in dairy cows in Sweden. Prev Vet Med 1991; 10: 261-71.
28. Erb HN, and White ME. Incidence rates of cystic follicles in Holstein cows according to 15-day and 30-day intervals. Cornell Vet 1981; 71: 326-31.
29. Erickson GG, Hsueh AJW, Quigley ME, Raber RW, and Yen SSC. Functional studies of aromatase activity in human granulosa cells from normal and polycystic ovaries. J Clin Endocrinol and Metab 1979; 49: 514-9.
30. Eyestone WH, and Ax RL. A review of ovarian follicular cysts in cows, with comparisons to the condition in women, rats and rabbits. Theriogenology 1984; 22: 109-25.
31. Farin PW, Youngquist RS, Parfet JR, and Garverick HA. Hormonal changes by the development of ovarian cysts in cows. Theriogenology 1990; 34: 633-41.
32. Franks S, Robinson S, and Willis DS. Nutrition, insulin and polycystic ovary syndrome. Rev Reprod 1996; 1: 47-54.
33. Garverick HA. Ovarian follicular cysts in dairy cows. J Dairy Sci 1997; 80: 995-1004.
34. Ginther OJ. Selection of the dominant follicle in cattle and horses. Anim Reprod Sci 2000; 60-61: 61-79.
35. Ginther OJ, Beg MA, Bergfelt DR, Donadeu FX, and Kot K. Follicle selection in monovular species - minireview. Biol Reprod 2001; 65: 638-47.
36. Ginther OJ, Bergfelt DR, Kulick LJ, and Kot K. Pulsatility of systemic FSH and LH concentrations during follicular-wave development in cattle. Theriogenology 1998; 50: 507-19.
37. Ginther OJ, Bergfelt DR, Kulick LJ, and Kot K. Selection of the dominant follicle in cattle: establishment of follicle deviation in less than 8 hours through depression of FSH concentrations. Theriogenology 1999; 52: 1079-93.
38. Ginther OJ, Bergfelt DR, Kulick LJ, and Kot K. Selection of the dominant follicle in cattle: role of two-way functional coupling between follicle-stimulating hormone and the follicles. Biol Reprod 2000; 62: 920-7.
39. Ginther OJ, Bergfelt DR, Kulick LJ, and Kot K. Selection of the dominant follicle in cattle: role of estradiol. Biol Reprod 2000; 63: 383-9.
40. Ginther OJ, Kot K, Kulick LJ, and Wiltbank MC. Emergence and deviation of follicles during the development of follicular waves in cattle. Theriogenology 1997; 48: 75-87.
41. Gong JG, Campbell BK, Bramley TA, Gutierrez CG, Peters AR, and Webb R. Suppression in the secretion of follicle-stimulating hormone and luteinizing hormone, and ovarian follicle develoment in heifers continuously infused with a gonadotropin-releasing hormone agonist. Biol Reprod 1996; 55: 68-74.
42. Grimard B, Humblot P, Ponter AA, Mialot JP, Sauvant D, and Thibier M. Influence of postpartum energy restriction on energy status, plasma LH and oestradiol secretion and follicular development in suckled beef cows. J Reprod Fertil 1995; 104: 173-9.
43. Gutierrez-Aguilar CG. The effect of nutrition and metabolic hormones on follicular development in cattle. PhD Dissertation, University of Edinburgh, 1997: 146-66.
44. Haavisto AM, Pettersson K, Bergendahl M, Virkamäki A, and Huhtaniemi I. Occurrence and biological properties of a common genetic variant of luteinizing hormone. J Clin Endocrinol and Metab 1995; 80: 1257-63.
45. Hamilton SA, Garverick HA, Keisler DH, Xu ZZ, Loos K, Youngquist RS, and Salfen BE. Characterization of ovarian follicular cysts and associated endocrine profiles in dairy cows. Biol Reprod 1995; 53: 890-8.
46. Hooijer GA, Kaal-Lansbergen LMTE, Lubbers R, en Arendonk JAM van. Cysteuze eierstokken te lijf. Veeteelt 1999; 16: 296-8.
47. Hooijer GA, Lubbers RBF, Ducro BJ, Arendonk JAM van, Kaal-Lansbergen LMTE, and Lende T van der. Genetic parameters for cystic ovarian disease in Dutch black and white dairy cattle. J Dairy Sci 2001; 84: 286-91.
48. Huszenicza G, Haraszti J, Molnár L, Solti L, Fekete S, Ekés K, and Yaro AC. Some metabolic characteristics of dairy cows with different post partum ovarian function. J Vet Med A 1988; 35: 506-15.
49. Ireland JJ. Control of follicular growth and development. J Reprod Fertil, supplement 1987; 34: 39-54.
50. Jánosi S, Huszenicza G, Kulcsár M, and Kóródi P. Endocrine and reproductive consequences of certain endotoxin-mediated diseases in farm animals: a review. Acta Vet Hung 1998; 46: 71-84.
51. Jeffcoate IA, and Ayliffe TR. An ultrasonographic study of bovine cystic ovarian disease and its treatment. Vet Rec 1995; 136: 406-10.
52. Kawate N, Inaba T, and Mori J. A quantitative comparison in the bovine of steroids and gonadotropin receptors in normally developing follicles and in follicular and luteinized cysts. Anim Reprod Sci 1990; 23: 273-81.
53. Kesler DJ, and Garverick HA. Ovarian cysts in dairy cattle: a review. J Anim Sci 1982; 55: 1147-59.
54. Kesler DJ, Garverick HA, Caudle AB, Bierschwal CJ, Elmore RG, and Youngquist RS. Testosterone concentrations in plasma of dairy cows with ovarian cysts. J Dairy Sci 1979; 62: 1825-8.
55. Kesler DJ, Garverick HA, Caudle AB, Elmore RG, Youngquist RS, and Bierschwal CJ. Reproductive hormone and ovarian changes in cows with ovarian cysts. J Dairy Sci 1980; 63: 166-70.
56. Kesner JS, Padmanabhan V, and Concey EM. Estradiol induces and progesterone inhibits the preovulatory surges of luteinizing hormone and follicle-stimulating hormone in heifers. Biol Reprod 1982; 26: 571-8.
57. Kirk JH, Huffman EM, and Lane M. Bovine cystic ovarian disease: hereditary relationships and case study. J Am Vet Med Assoc 1982; 181: 474-6.
58. nd ed., Philadelphia: WB Saunders Co.; 1986: 117-25.
59. Kolb E. Recent findings on secretion of gonadoliberin in sheep and cattle-Regulation and controllability (review paper). Mh Vet Med 1989; 44: 490-3.
60. Laporte HM, Hogeveen H, Schukken YH, and Noordhuizen JPTM. Cystic ovarian disease in Dutch dairy cattle I. Incidence, risk factors and consequences. Livest Prod Sci 1994; 38: 191-7.
61. Leathem JH. Hormonal influences on the gonadotropin-sensitive hypothyroid rat ovary. Anat Rec 1958; 131: 487-97.
62. Lee CN, Cook DL, Parfet JR, Smith CA, Youngquist RS, and Garverick HA. Induction of persistent ovarian follicular structures following administration of progesterone near the onset of estrus in dairy cattle. J Dairy Sci 1988; 71: 3505-8.
63. Leslie KE, and Bosu WTK. Plasma progesterone concentrations in dairy cows with cystic ovaries and clinical response following fenprostalene. Can Vet J 1983; 24: 352-6.
64. Lopez-Diaz MC, and Bosu WTK. A review of cystic ovarian degeneration in ruminants. Theriogenology 1992; 37: 1163-83.
65. Marcek JM, Appell LH, Hoffman CC, Moredick PT, and Swanson V. Effect of supplemental ß-carotene on incidence and responsiveness of ovarian cysts to hormone treatment. J Dairy Sci 1985; 68: 71-7.
66. MartinTL, Fogwell RL, and Ireland JJ. Concentrations of inhibins and steroids in follicular fluid during development of dominant follicles in heifers. Biol Reprod 1991; 44: 693-700.
67. Matamaros IA, Cox NM, and Moore AB. Exogenous insulin and additional energy affect follicular distribution, follicular steroid concentrations, and granulosa cell human chorionic gonadotropin binding in swine. Biol Reprod 1990; 43: 1-7.
68. Mihm M, Austin EJ, Good TEM, Ireland JLH, Knight PG, Roche JF, and Ireland JJ. Identification of potential intrafollicular factors involved in selection of dominant follicles in heifers. Biol Reprod 2000; 63: 811-9.
69. Nakao T, Sugihashi A, Saga N, Tsunoda N, and Kawata K. Use of milk progesterone enzyme immunoassay for differential diagnosis of follicular cyst, luteal cyst, and cystic corpus luteum in cows. Am J Vet Res 1983; 44: 888-90.
70. Nanda AS, Ward WR, and Dobson H. The relationship between milk yield and cystic ovarian disease in cattle. Br Vet J 1989; 145: 39-45.
71. Nesbitt REL, Abdul-Karim RJ, Prior JT, Shelly TJ, and Rourke JE. Study of the effect of experimentally induced endocrine insults upon pregnant and non pregnant ewes III ACTH and propylthiouracil administration and the production of polycystic ovaries. Fertil Steril 1967; 18: 739-58.
72. Nessan GK, and King GJ. Relationship of peripheral estrogens and testosterone concentrations to sexual behavior in normal and cystic cows. Can Vet J 1981; 22: 9-11.
73. Nestler JE. Insulin regulation of human ovarian androgens. Hum Reprod 1997; 12, supplement 1: 53-62.
74. Nestler JE. Polycystic ovary syndrome: a disorder for the generalist. Fertil Steril 1998; 70: 811-2.
75. Nett TM. Function of the hypothalamic-hypophysial axis during the post-partum period in ewes and cows. J Reprod Fertil 1987; supplement 34: 201-13.
76. Nilsson C, Pettersson K, Millar RP, Coerver KA, Matzuk MM, and Huhtaniemi IT. Worldwide frequency of a common genetic variant of luteinizing hormone: an international collaborative research. Fertil Steril 1997; 67: 998-1004.
77. Opsomer G, Coryn M, Deluyker H, and Kruif A de. An analysis of ovarian dysfunction in high yielding dairy cows after calving based on progesterone profiles. Reprod Dom Anim 1998; 33: 193-204.
78. Opsomer G, Coryn M, Mijten P en Kruif A de. Post-partum anoestrus bij melkvee. Vlaams Diergeneesk Tijdsch 1997; 66: 61-7.
79. Opsomer G, Gröhn Y.T, Hertl J, Coryn M, Deluyker H, and Kruif A de. Risk factors for postpartum ovarian dysfunction in high producing dairy cows in Belgium: a field study. Theriogenology 2000; 53: 841-57.
80. Opsomer G, Wensing T, Laevens H, Coryn M, and Kruif A de. Insulin resistance: the link between metabolic disorders and cystic ovarian disease in high yielding dairy cows? Anim Reprod Sci 1999; 56: 211-22.
81. Ozturk M, Smith RF, and Dobson H. Effect of prolonged exposure to oestradiol on subsequent LH secretion in ewes. J Reprod Fertil 1998; 114: 1-9.
82. Padmanabhan V, Keech C, and Convey ME. Cortisol inhibits and ACTH has no effect on LHRH-induced release of LH from bovine pituitary cells in vitro. Endocrinology 1983; 112: 1782-7.
83. Peter AT, and Bosu WTK. Influence of intrauterine infections and follicular development on the response to GnRH administration in post-partum dairy cows. Theriogenology 1988; 29: 1163-75.
84. Peter AT, Bosu WTK, and Dedecker RJ. Suppression of preovulatory luteinizing hormone surges in heifers after intrauterine infusions of Eschcrichia coli endotoxin. Am J Vet Res 1989; 50: 368-73.
85. Peters AR, and Lamming GE. Regulation of ovarian function in the post partum cow: an endocrine model. Vet Rec 1986; 118: 236-9.
86. Price CA, and Silva JM. Intracellular regulation of P450 aromatase by FSH and insulin in bovine granulosa cells. J Reprod Fertil 1999; Abstract Series 23: 5.
87. Rajamahendran R, and Taylor C. Characterization of ovarian activity in post partum dairy cows using ultrasound imaging and progesterone profiles. Anim Reprod Sci 1990; 22: 171-80.
88. Rajaniemi HJ, Ronbell L, Kauppila A, Ylostalo R, and Viako R. Luteinizing hormone receptors in ovarian follicles of patients with polycystic ovarian disease. J Clin Endocrinol Metab 1980; 51: 1054-7.
89. Refsal KR, Jarrin-Maldonado JH, and Nachreiner RF. Endocrine profiles in cows with ovarian cysts experimentally induced by treatment with exogenous estradiol or adrenocorticotropic hormone. Theriogenology 1987; 28: 871-89.
90. Refsal KR, Jarrin-Maldonado JH, and Nachreiner RF. Basal and estradiol-induced release of gonadotropins in dairy cows with naturally occuring ovarian cysts. Theriogenology 1988; 30: 679-93.
91. Refsdal AO. Ovariecyster hos mclkekyr. Norsk Veterinærtidsskrift 1982; 94: 789-96.
92. Ribadu AY, Nakada K, Moriyoshi M, Zhang WC, Tanaka Y, and Nakao T. The role of LH pulse frequency in ACTH-induced ovarian follicular cysts in heifers. Anim Reprod Sci 2000; 64: 21-31.
93. Riddlesberger MM, Kuhn EP, and Munschauer RW. The association of juvenile hypothyroidism and cystic ovaries. Radiology 1981; 139: 77-80.
94. Rittmaster RS, Deshwal N, and Lehman L. The role of adrenal hyperandrogenism, insulin resistance, and obesity in the pathogenesis of polycystic ovarian syndrome. J Clin Endocrinol Metab 1993; 76: 1295-9.
95. Rivera GM, Chandrasekher YA, Evans AC, Giudice LC, and Fortune JE. A potential role for insulin-like growth factor binding protein-4 proteolysis in the establishment of ovarian follicular dominance in cattle. Biol Reprod 2001; 65: 102-11.
96. rd ed., Vermont: Woodstock; 1986: 421-33.
97. Roche JF, and Diskin MG. Hormonal regulation of reproduction and interactions with nutrition in female ruminants. In: v Engelhardt W, Leonhard-Marek S, Breves G, Giesecke D (editors). Ruminant Physiology: Digestion, Metabolism, Growth and Reproduction. Proceedings of the Eighth International Symposium on Ruminant Physiology. Stuttgart: Ferdinand Enke Verlag; 1995: 409-28.
98. th Congress of the World Association for Buiatrics, Edinburgh 8-12 July 1996, United Kingdom; 1996: p. 157-63.
99. Savio JD, Keenan L, Boland MP, and Roche JF. Pattern of growth of dominant follicles during the oestrous cycle in heifers. J Reprod Fertil 1988; 83: 663-71.
100. Savio JD, Boland MP, Hynes N, and Roche JF. Resumption of follicular activity in the early post partum period of dairy cows. J Reprod Fertil 1990; 88: 569-80.
101. Schallenberger E, and Peterson AJ. Effect of ovariectomy on tonic gonadotrophin secretion in cyclic and post-partum dairy cows. J Reprod Fertil 1982; 64: 47-52.
102. Schallenberger E, and Prokopp S. Gonadotrophins and ovarian steroids in cattlE IV Re-establishment of the stimulatory feedback action of oestradiol-17 beta on LH and FSH. Acta Endocrinol 1985; 109: 44-9.
103. Simpson RB, Chase CC, Spicer LJ, Vernon RK, Hammond AC, and Rae DO. Effect of exogenous insulin on plasma and follicular insulin-like growth factor I, insulin-like growth factor binding protein activity, follicular oestradiol and progesterone, and follicular growth in super-ovulated Angus and Brahman cows. J Reprod Fertil 1994; 102: 483-92.
104. Spicer LJ, Chamberlain CS, and Morgan GL. Proteolysis of insulin-like growth factor binding proteins during preovulatory follicular development in cattle. Dom Anim Endocrinol 2001; 21: 1-15.
105. Spicer LJ, and Echternkamp SE. The ovarian insulin and insulin-like growth factor system with an emphasis on domestic animals. Dom Anim Endocrinol 1995; 12: 223-45.
106. Stoebel DP, and Moberg GP. Repeated acute stress during the follicular phase and luteinizing hormone surge of dairy heifers. J Dairy Sci 1982; 65: 92-6.
107. Stoebel DP, and Moberg GP. Effect of adrenocorticotropin and cortisol on luteinizing hormone surge and estrous behavior of cows. J Dairy Sci 1982; 65: 1016-24.
108. Sunderland SJ, Knight PG, Boland MP, Roche JF, and Ireland JJ. Alterations in intrafollicular levels of different molecular mass forms of inhibin during developmet of follicular- and luteal-phase dominant follicles in heifers. Biol Reprod 1996; 54: 453-62.
109. Swedish Agriculture. Statistics Yearbook for 1976 to 1977. 1978: 114.
110. Thorsoe H. Development of polycystic ovaries following thyroidectomy. Acta Endrocrinol 1962; 40: 161-74.
111. Torres E, Nakao T, Osawa T, Moriyoshi M, Kawata K, and Nakada K. Pospartum adrenal, pituitary and ovarian functions in dairy cows. J Vet Med A 1997; 44: 133-42.
112. Turzillo AM, and Fortune JE. Suppression of the secondary FSH surge with bovine follicular fluid is associated with delayed ovarian follicular development in heifers. J Reprod Fertil 1990; 89: 643-53.
113. Watson ED, and Munro CD. Adrenal progesterone production in the cow. Br Vet J 1984; 14: 300-6.
114. White ME, and Erb HN. Treatment of ovarian cysts in dairy cattle. A decision analysis. Cornell Vet 1980; 70: 247-57.
115. Woolums AR, and Peter AT. Cystic Ovarian Condition in Cattle. Part I Folliculogenesis and Ovulation. Compend Contin Educ Pract Vet (Food Animal) 1994; 16: 935-42.
116. Woolums AR, and Peter AT. Cystic Ovarian Condition in Cattle. Part II Pathogenesis and Treatment. Compend Contin Educ Pract Vet (Food Animal) 1994; 16: 1247-52.
117. Wright IA, Rhind SM, Smith AJ, and Whyte TK. Effects of body condition and estradiol on luteinizing hormone secretion in post-partum beef cows. Dom Anim Endocrinol 1992; 9: 305-12.
118. Yen SSC. Polycystic Ovary Syndrome (Hyperandrogenic Chronic Anovulation). In: Reproductive endocrinology: physiology, pathophysiology and clinical management. Philadelphia (Pa.): Saunders; 1999: p. 436-78.
119. Yoshioka K, Iwamura S, and Kamomae H. Ultrasonic observations on the turnover of ovarian follicular cysts and associated changes of plasma LH, FSH, progesterone and oestradiol-17ß in cows. Res Vet Sci 1996; 61: 240-4.
120. Yoshioka K, Iwamura S, and Kamomae H. Changes of ovarian structures, plasma LH, FSH, progesterone and estradiol-17ß in a cow with ovarian cysts showing spontaneous recovery and relapse. J Vet Med Sci 1998; 60: 257-60.
121. nd ed., Philadelphia: WB Saunders Co.; 1986: 243-6.
122. Zaied AA, Garverick HA, Kesler DJ, Bierschwal CJ, Elmore RG, and Youngquist RS. Luteinizing hormone response to estradiol benzoate in cows postpartum and cows with ovarian cysts. Theriogenology 1981; 16: 349-58.