Post-partum anoestrus in dairy cows: A review

Veterinary Quarterly

Volumn 18, Issue 2, 1996, Pages 68-75

  Opsomer, G ^a   Mijten, P ^a   Coryn, M ^a   de Kruif, A ^a  

^a GHENT UNIVERSITY   (Belgium)

Author keywords

[No Author keywords available]

Indexed keywords

ANIMAL; ANIMAL DISEASE; BREEDING; CATTLE; CATTLE DISEASE; FEMALE; INCIDENCE; METHODOLOGY; OVARY; OVULATION; OVULATION DETECTION; PATHOPHYSIOLOGY; PHYSIOLOGY; PREGNANCY; PREGNANCY RATE; PUERPERIUM; REPRODUCTION; REVIEW; TIME; UTERUS;

ANIMALS; BREEDING; CATTLE; CATTLE DISEASES; FEMALE; INCIDENCE; OVARY; OVULATION; OVULATION DETECTION; POSTPARTUM PERIOD; PREGNANCY; PREGNANCY RATE; REPRODUCTION; TIME FACTORS; UTERUS;

EID: 0030163017     PISSN: 01652176     EISSN: 18755941     Source Type: Journal    
DOI: 10.1080/01652176.1996.9694620     Document Type: Article

References (133)

1. Arthur OH, Noakcs DE, and Pearson H. Veterinary reproduction and obstetrics. Baillicrc Tindall, London/Philadelphia/Toronto/Mexico City/Rio de Janeiro/Sydney/Tokyo/Hong Kong; 5th edition 1985.
2. Ball P. Milk progesterone profiles in relation to dairy herd fertility, Brit Vet J 1982; 138:546–51.
3. Ball P. Fertility problems in dairy herds. In practice 1983: 189–94.
4. Barth T, Kießling J, Walther A, und Zulle D. Ergebnisse diagnostischer Untersuchungen mit dem Milchprogesterontcst bei Kühen mit Anöstrie post partum. Monatsh Veterinärmed 1986; 41:289–92.
5. Barth T, Kießling J, Walther A, Koban G, Mai H, Beyer R, und Brauer E. Untersuchungsergebnisse zum Vorkommen, zur Diagnose und Therapie der Azyklie bei Kühen. Monatsh Veterinärmed 1990; 45: 329–33.
6. Bartlett PC, Kirk J, Coe P, Marteniuk S, and Mather EC. Descriptive epidemiology of ancstrus in Michigan Holstcin-Fresian cattlc. Theriogcnology 1987; 27:459–76.
7. Bostcdt II. Kozicki LE, Finger KH, und Karg H. Untersuchungen über den Einfluß verschiedener Haltungsbcdingungen auf postpartale Regenerations-vorgänge am Genitaltrakt von Milchkühen unter besonderer Berücksichtigung der Progcsteron-profilc. Reprod Dornest Anim 1985; 20:17–33.
8. Boyd H. Anoestrus in cattle. Vet Rec 1977; 100: 150–3.
9. Bretzlaff KN. Rationale for treatment of endometritis in the dairy cow. Vet clin N Am Food A 1987; 3:593–607.
10. Buch NC, Tyler WS, and Casida LE. Postpartum estrus and involution of the uterus in an experimental herd of Holstein-Fresian cows. J Dairy Sei 1955;38:73–9.
11. Buchholz GW, und Busch W. Untersuchungen über Beziehungen zwischen ovarieller Aktivität und Utcrusinvolution bei Kühen post partum. Monatsh Veterinärmed 1976:95–7.
12. Bulman DC, and Lamming GE. Milk progesterone levels in relation to conception, repeat breeding and factors influencing acyclicity in dairy cows. J Reprod Fertil 1978; 54:447–58.
13. Bulman DC, and Wood PDP. Abnormal patterns of ovarian activity in dairy cows and their relationships with reproductive performance. AnimProd 1980; 30: 177–88.
14. Bush W, Kuhnkc J, Mcums D, und Lusky K. Untersuchungen zur Behandlung der Pyometra beim Rind. Monatsh Veterinärmed 1983; 38; 331–5.
15. Butler WR, and Smith RD. Interrelationships between energy balance and postpartum reproductive function in dairy cattlc. J Dairy Sei 1989; 72; 767–83.
16. Butler WR. Everett RW, and Coppock CE. The relationships between energy balance, milk production and ovulation in postpartum Holstein cows. J Anim Sei 1981; 53:742–8.
17. Callahan CJ. Erb RE, Surve AH. and Randel RD. Variables influencing ovarian cycles in postpartum dairy cows. J Anim Sei 1971; 33: 1053–9.
18. Canfield RW, and Butler WR. Energy balance, first ovulation and the effects of naloxone on LH secretion in early postpartum dairy cows. J AnimSci 1991;69:740–6.
19. Cook DL, Smith CA, Parfet JR, Youngquist RS, Brown EM, and Garvcrick HA. Fate and turnover rate of ovarian follicular cysts in dairy cattlc. J Reprod Fertil 1990; 90:37–46.
20. Dachir S, Blake RW, and Harms PG. Ovarian activity of Holstein and Jersey Cows of diverse transmitting abilities for milk. J Dairy Sei 1984; 67: 1776–82.
21. Day N. The diagnosis, differentiation and pathogenesis of cystic ovarian disease. Vet Med 1991; 86:753–60.
22. Bois CHE de. Endometritis cn vruchtbaarheid bij het rund. PhD Thesis, University of Utrecht, the Netherlands (1961).
23. Kruif A de en Brand A. Bchandcling van subocstus bij runderen met prostaglandinen. Tijdschr Diergeneeskd 1976; 101:491–3.
24. Kruif A de en Mijten P. De praktische tocpassing van ccn bedrijfsbe-gclcidingsprogramma voor melkvcc. Vlaams Dicrgen Tijdschr 1989; 58:195–9.
25. Kruif A de. Een ondcrzock van runderen in anoestrus. Tijdschr Diergeneeskd 1977; 102:247–53.
26. Dijkhuizcn AA, Stclwagen J, and Rcnkcma JA. Economic aspects of reproductive failure level in dairy cattlc. 1. Financial loss at farm level. Prcv Vet Med 1984/1985; 3:251–63.
27. Dufour JJ, and Roy GL. Distribution of ovarian follicular populations in the dairy cow within 35 days after parturition. J Reprod Fertil 1985; 73:229–35.
28. Elliott L, McMahon KJ, and Gier HT. Uterus of the cow after parturition: Bacterial content. Am J Vet Res 1968; 29:77–81.
29. Elsacsscr F, Ellcndorff F, und Smidt D. Die Milchprogesteron-Bcstimmung als Mittel zur Objektivierung des Fruchtbarkeitsstatus von Milchkuhherden in der Post-partum Phase. Dtsch Ticrärztl Wochsch 1979; 86:53–4.
30. Enbcrgs H, und Völl St. Zyklusstörungen bei Milchkühen mit Spitzenleistungen. Prakt Tierarzt 1991; 11:959–71.
31. Esslemont RJ, Bailie JH. and Cooper MJ. Fertility and profitable milk production, ln: ‘Fertility management in dairy cattle’. eds Esslemont RJ, Bailie JH, and Cooper MJ. Collins, London 1985: 18–38.
32. Esslemont RJ. Economic aspects related to cattle infertility and the postpartum interval. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallcnbcrgcr E. Current topics in veterinary medicine and animal science. Martinus Nijhoff Publishers, The Hague 1982; 20:442–58.
33. Ethcrington WG, Christie KA, Walton JS, Leslie KE, Wickstrom S, and Johnson WH. Progesterone profiles in postpartum Holstein dairy cows as an aid in the study of retained fetal membranes, pyomctra and anestrus. Theriogcnology 1991; 35: 731–46.
34. Fagan JG, and Roche JF. Reproductive activity in postpartum dairy cows based on progesterone concentrations in milk or rectal cxamina-tion. Irish Vet J 1986; 40:124–31.
35. Farin PW, Ball L, Olson JD, Mortimer RG, Jones RL, Adney WS, and McChesney AE. Effect of Actinomyces pyogenes and gram-negative anaerobic bacteria on the development of bovine pyomctra. Theriogenology 1989; 31:979–89.
36. Farin PW, Youngquist RS, Parfct JR. and Garverick HA. Diagnosis of luteal and follicular ovarian cysts in dairy cows by sector scan ultrasonography. Theriogenology 1990; 34:633–42.
37. Fernandes LC. Thatcher WW, Wilcox CJ, and Call EP. LH Release in response to GnRH during the postpartum period of dairy cows. J Anim Sei 1978;46:443–8.
38. Fonseca FA, Britt JH, McDaniel BT, Wilk JC, and Rakes AH. Reproductive traits of Holsteins and Jerseys. Effects of age, milk yield and clinical abnormalities on involution of cervix and uterus, ovulation, estrous cycles, detection of estrus, conception rate and days open. J Dairy Sei 1983; 66: 1128–47.
39. Foote RH. Estrus detection and estrus detection aids. J Dairy Sei 1975; 58:248.
40. Foster JP, Lamming GE, and Peters AR. Short-term relationships between plasma LH, FSIl and progesterone concentrations in post-partum dairy cows and the effect of GnRH injection. J Reprod Fert 1980; 59:321–7.
41. Francos G, and Mayer E. Analysis of fertility indices of cows with extended postpartum ancstrus and other reproductive disorders compared to normal cows. Theriogenology 1988; 29:399–412.
42. Gier HT, and Marion GB. Uterus of the cow after parturition: involutional changes. Am J Vet Res 1968; 29:83.
43. Giessen RC van. Intravaginale bchandeling van cysteuze ovariclc follikcls bij het rund met progestcron (PR1D®) waarbij ccn bchandeling met GnRH nict tot resultaat leiddc. Tijdschr Diergeneeskd 1981; 106: 881–3.
44. th internat. Congress Diseases in cattle. Tel Aviv (Israël) 1980; 2:895–905.
45. Griffin JFT, Hartigan PJ, and Nunn WR. Non-specific uterine infection and bovine fertility. Theriogenology 1974; 1: 107–14.
46. Gruncrt E. Zur Ovardystrophie beim Rind. Collegium Veterinarium 1981:73–7.
47. Gruncrt E. Ursachen und Behandlungsmöglichkeiten der Endometritis beim Rind. Collegium Veterinarium XVII 1986:43–7.
48. Gustafsson B, Backstrom G, and Edqvist L-E. Treatment of bovine pyomctra with prostaglandin F2a: An evaluation of a field study. Theriogenology 1976; 6:45–50.
49. Haraszti J, Huszcnicza G, Molnar L, Solti L, and Csemus V. Postpartal ovarian activity of healthy cows and those affected by subclinical metabolic disorders. Anim Reprod Sei 1985; 9: 125–36.
50. Haraszti J. Die diagnostische und prognostische Bedeutung der Ketonurie bei den Fruchtbarkeitsstörungen des Rindes. Dtsch Tierärztl Woch 1990; 97:407–11.
51. Harrison RO, Ford SP, Young JW, Conley AJ, and Freeman AE. Increased milk production versus reproductive and energy status of high producing dairy cows. J Dairy Sei 1990; 73:2749–58.
52. Hopkins SM. Bovine anestrus. In: Current therapy in Theriogenology, ed Morrow DA. WB Saunders Company, Philadelphia/ London/Toronto/Mexico City/Rio de Janeiro/Sydney/Tokyo/Hong Kong 1986:247–50.
53. Huffman EM, Mortimer RG, Olson JD, Ball L, and Farin PW. Risk factors for prebreeding pyomctra on four Colorado dairy farms. Prev Vet Med 1984; 2:785–90.
54. Hussain AM. Bovine uterine defence mechanisms: A review. J Vet Med 1989; 36:641–51.
55. Hussain AM, and Daniel RCW. Bovine normal and abnormal reproductive and endocrine functions during the postpartum period: A review. Reprod Domest Animl 991;26:101-ll.
56. Huszcnicza G, Haraszti J, Molnàr L, Solti L, Fckcte S, Ekes K, and Yaro AC. Some metabolic characteristics of dairy cows with different post partum ovarian function. J Vet Med A 1988; 35:506–15.
57. Huszenicza G, Molnar L, Solti L, and Haraszti J. Postpartal ovarian function in Holstein and crossbred cows on large scale farms in Hungary. J Vet Med A 1987; 34:249–63.
58. Ijaz A, Fahning ML, and Zemjanis R. Treatment and control of cystic ovarian disease in dairy cattle: A review. Brit Vct J 1987; 143:226–37.
59. Kähn W. Gelbkörper mit und ohne Hohlraum bei Rindern. Tierärztl Praxis 1989; 4:1–6.
60. Kaidi R, Brown PJ, and David JSE. Uterine involution in cattle. The Veterinary Annual 1991; 31:38–50.
61. Kamimura S, Ohgi T, Takahaski M, and Tsukamoto T. Postpartum resumption of ovarian activity and uterine involution monitored by ul-trasonography in Holstein cows. J Vet Med Sei 1993; 55: 643–7.
62. Karg H, und Schallcnbcrgcr E. Regulation der ovariellen Steroidhormonsekretion post partum. Wien Tierärztl Monat 1983- 70238–43.
63. Kesler DJ, Garverick HA, Caudlc AB, Bierschwal CJ, Elmore RG, and Youngquist RS. Clinical and endocrine responses of dairy cows with ovarian cysts to GnRH and PFG2α. J Anim Sci 1978;46:719–25.
64. Kesler DJ, and Garverick HA. Ovarian cysts in dairy cattle: A review. J Anim Sei 1982; 55: 1147–59.
65. Kindahl H, Edqvist L-E, Larsson K, and Malmqvist A. Influence of prostaglandins on ovarian function postpartum. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallenberger E. Current topics in veterinary medicine and animal science Vol 20 MartinusNijhoff Publishers, The Hague 1982: 173–96.
66. Kindahl H, Odensvik K, Aiumlamai S, and Frcdriksson G. Utero-ovarian relationships during the bovine postpartum period. Anim Reprod Sei 1992; 28:363–9.
67. King GJ, Humik JF, and Robertson HA. Ovarian function and estrus in dairy cows during early lactation. J Anim Sei 1976; 42:688–92.
68. Lamming GE, and Bulman DC. The use of milk progesterone radioimmunoassay in the diagnosis and treatment of subfertility in dairy cows. Brit Vet J 1976; 132:507–17.
69. Lamming GE, Peters AR, Riley GM, and Fisher MW. Endocrine regulation of postpartum function. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallenberger E. Current topics in veterinary medicine and animal science Vol 20 Martinus Nijhoff Publishers, The Hague 1982:148–72.
70. Lamming GE, Wathcs DC, and Peters AR. Endocrine patterns of the post-partum cow. J Reprod Fertil 1981; 30: 155–70.
71. Larsson K, Jansson L, Berglund B, Edqvist L-E, and Kindahl H. Postpartum reproductive performance in dairy cows. I: Influence of animal, breed and parity. Acta Vet Scand 1984; 25:445–61.
72. Lehrer AR, Lewis OS, and Aizinbud E. Oestrus detection in cattle: Recent developments. Anim Reprod Sei 1992; 28:355–61.
73. Leslie KE, and Bosu WTK. Plasma progesterone concentrations in dairy cows with cystic ovaries and clinical responses following treatment with fenprostalene. Can Vet J 1983; 24:352–6.
74. Lindell J-O. Kindahl H, Jansson L, and Edqvist L-E. Postpartum release of prostaglandin F2a and uterine involution in the cow. Theriogenology 1982; 17:237–45.
75. Lopez-Diaz MC, and Bosu WTK. A review and an update of cystic ovarian degeneration in ruminants. Theriogenology 1992; 37: 1163–83.
76. Lucy MC, Staples CR, Michel FM, and Thatcher W W. Energy balance and size and number of ovarian follicles detected by ultrasonography in early postpartum dairy cows. J Dairy Sei 1991; 74:473–82.
77. MacMillan KL, and Peterson AJ. A new intravaginal progesterone releasing device for cattle (C1DR-B) for oestrous synchronisation, increasing pregnancy rates and the treatment of post partum anoestrus. Anim Reprod Sei 1993; 33: 1–25.
78. Madej A, Kindahl H, Woyno W, Edqvist L-E, and Stupnicki R. Blood levels of 15-kcto-l3, 14-dihydroprostaglandin F2n during the postpartum period in primiparous cows. Theriogenology 1984; 21:279–87.
79. Marion GB, and Gier HT. Factors affecting bovine ovarian activity after parturition. J Anim Sei 1968; 27:1621–6.
80. Markusfeld O. Inactive ovaries in high-yielding dairy cows before service: Aetiology and effect on conception. Vet Rec 1987; 121: 149–53.
81. Masilo BS, Stevenson JS, Schalles RR, and Shirley JE. Influence of genotype and yield and composition of milk on interval to first postpartum ovulation in milked beef and dairy cows. J Anint Sei 1992; 70: 379–85.
82. Mayer E, Francos G, und Nervia A. Eierstockbefundc und FertilitätsParameter bei Kühen mit ‘unbeobachteter Brunst’. Tierärztl Umschau 1987;42:506–9.
83. McLeod BJ, and Williams ME. Incidence of ovarian dysfunction in postpartum dairy cows and the effectiveness of its clinical diagnosis and treatment. Vet Rec 1991; 128: 121–4.
84. McNatty KP, Hudson N, Gibb M, Henderson KM. Lun S, Heath D. and Montgomery GW. Seasonal differences in ovarian activity in cows. J Endocrinol 1984; 102: 189–98.
85. Moberg GP. How behavioural stress disrupts the endocrine control of reproduction in domestic animals. J Dairy Sei 1991; 74:304–11.
86. Möller K. A review of uterine involution and ovarian acivity during the postparturient period in the cow. New Zeal Vet J 1970; 18:83–90.
87. Morrow DA, Roberts SJ, McEntee K, and Gray HG. Postpartum ovarian activity and uterine involution in dairy cattle. J Am Vet Med Assoc 1966; 149: 1596–1609.
88. Morrow DA, Roberts SJ, and McEntee K. Postpartum ovarian activityand involution of the uterus and cervix in dairy cattle. IV. A review of post partum ovarian activity and involution of the uterus and cervix in dairy cattle. Cornell Vet 1969; 59: 134–54.
89. Munro CD, Boyd II, Watson ED, McBride B, Martin B, Booth JM, and Holdsworth RJ. Monitoring pre-service reproductive status in dairy cows. Vet Rec 1982; 110:77–81.
90. th World Buiatrics Congress: Salvador dc Bahia 1990:203–7.
91. Nett TM. Function of the hypothalamic-hypophysial axis during the post-partum period in ewes and cows. J Reprod Fertil 1987; 34:201–13.
92. O’Fanell KJ. Effects of management factors on the reproductive performance of the post partum dairy cow. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallcnbergcr E. Current topics in veterinary medicine and animal science Vol 20 Martinus Nijhoff Publishers, The Hague 1982:510–29.
93. Olson JD, Brctzlaff KN, Mortimer RG, and Ball L. The metritis-pyomctra complex. In: ‘Current therapy in Theriogcnology’, ed Morrow DA. WB Saunders Company, Philadelphia/London/Toronto/Mexico City/Rio de Janciro/Sydney/Tokyo/Hong Kong 1986:227–36.
94. Paisley LG, Mickelsen WD, and Anderson PB. Mechanisms and therapy for retained fetal membranes and uterine infections of cows: A review. Theriogenology 1986; 25:353–81.
95. Peters AR, and Lamming GE. Reproductive activity of the cow in the post-partum period: II. Endocrine patterns and induction of ovulation. Brit Vet J 1984; 140:269–80.
96. Peters AR, and Lamming GE. Regulation of ovarian function in the postpartum cow: An endocrine model. Vet Rcc 1986; 118:236–9.
97. Pirchncr F, Zwiaucr D, Butler IV, Claus R, and Karg H. Environmental and genetic influences on post-partum milk progesterone profiles of cows. Z Tierzüchtg Züchtsbiol 1983; 100:304–15.
98. Plunkett SS, Stevenson JS, and Call F.P. Prostaglandin F2a for lactating dairy cows with a palpable corpus luteum but unobserved estrus. J Dairy Sei 1984;67:380–7.
99. Radostits OM, Leslie KF, and Fetrow J. Herd Health: Food animal production medicine. WB Saunders company, Philadelphia/London/ Toronto/Montreal/Sydncy/Tokyo. 2nd edition 1994: 141–58.
100. Rajamahendran R, and Taylor C. Characterization of ovarian activity in postpartum dairy cows using ultrasound imaging and progesterone profiles. Anim Reprod Sei 1990; 22: 171–80.
101. Roche JF, Crowe MA, and Boland MP. Postpartum anoestrus in dairy and beef cows. Anim Reprod Sei 1992; 28:371–8.
102. Ruiz FJ, Oltcnacu PA, and Smith RD. Cost-bcncfit evaluation of on-farm milk progesterone testing to monitor return to cyclicity and to classify ovarian cysts. J Dairy Sei 1992; 75:1036.
103. Saiduddin S, Riesen JW, Tyler WJ, and Casida LE. Relation of postpartum interval to pituitary gonadotropins, ovarian follicular development and fertility in dairy cows. In Research Bulletin 270: ‘Studies on the postpartum cow’. The University ofWisconsin, 1968: 15–22.
104. 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; 88:569–79.
105. Savio JD, Boland MP, and Roche JF. Development of dominant follicles and length of ovarian cycles in post-partum dairy cows. J Reprod Fertil 1990; 88:581–91.
106. Schallenberger E. Charakterisierung von Sekretionsrythmen der Gonadotropine und Ovarsteroide während des Brunstzyklus, der Gravidität und post partum beim Rind. Advances in Veterinary Medicine 1990; 40: 117.
107. Schams D, Schallenberger E, Menzer Ch, Stangl J, Zottmcier K, Hoffmann B, and Karg H. Profiles of LH, FSH and progesterone in postpartum dairy cows and their relationship to the commencement of cyclic functions. Theriogcnology 1978; 10:453–68.
108. Schirar A, and Martinet J. Post partum ovarian activity and its interaction with the uterus in resuming cyclic activity post partum. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallenberger E. CurTcnt topics in veterinary medicine and animal science Vol 20 Martinus Nijhoff Publishers, The Hague 1982: 67–94.
109. Schmidt GH. Effect of length of calving intervals on income over feed and variable costs. J Dairy Sei 1989; 72:1605–11.
110. Schopper D, and Claus R. Progesterone concentrations in milkfat around ovulation in the dairy cow: differences between observed and silent heat. Reprod Domest Anim 1986; 21:237–40.
111. Schopper D, Schemer R, und Claus R. Analyse der Fruchtbarkcits-situation von Milchkühen post partum in Praxisbetrieben anhand von Progesteronprofilen. Reprod Dom Anim 1989; 24:67–78.
112. Schopper D, Schemer R, Weiler U, und Claus R. Einfluß der Milchleistung auf Fruchtbarkeitskriterien der Milchkuh post partum: Auswertung von Progesteronprofilen. Reprod Domest Anim 1993; 28: 225–35.
113. Scguin BE. Use of prostaglandin in cows with unobserved oestrus. Acta Vet Scand 1981; 77:343–52.
114. Spicer LJ, and Echtemkamp SE. Ovarian follicular growth, function and turnover in cattle: a review. J Anim Sei 1986; 62:428–51.
115. Sprecher DJ, Nebel RL, and Whittier WD. Predictive value of palpation per rectum vs milk and serum progesterone levels for the diagnosis of bovine follicular and luteal cysts. Theriogenology 1988; 30:701–9.
116. Staples CR, Thatcher WW, and Clarck JH. Relationship between ovarian activity and energy status during the early postpartum period of high producing dairy cows. J Dairy Sei 1990; 73: 938–47.
117. Stevenson JS, and Britt JH. Relationships among luteinizing hormone, estradiol, progesterone, glucocorticoids, milk yield, body weight and postpartum ovarian activity in Holstein cows. J Anim Sei 1979; 48: 570–7.
118. Stevenson JS, and Call EP. Influence of early estrus, ovulation and insemination on fertility in postpartum Holstein cows. Theriogenology 1983; 19:367–75.
119. Stevenson JS, and Purslcy JR. Resumption of follicular activity and interval to post partum ovulation after exogenous progcstins. J Dairy Sei 1994; 77:725–34.
120. Tennant B, and Peddicord RG. The influence of delayed uterine involution and endometritis on bovine fertility. Cornell Vet 1968; 58: 185–92.
121. Thatcher WW, and Wilcox CJ. Postpartum estrus as an indicator of reproductive status in the dairy cow. J Dairy Sei 1973; 56: 608–10.
122. Watts TL, and Fuquay JW. Response and fcrtiliy of dairy heifers following injection with prostaglandin F2n during early, middle or late diestrus. Theriogenology 1985; 23:655–61.
123. Webb R, Lamming GE, Haynes NB, and Foxcroft GR. Plasma progesterone and gonadotrophin concentrations and ovarian activity in postpartum dairy cows. J Reprod Fertil 1980; 59: 133–43.
124. White ME, and Erb HN. Treatment of ovarian cysts in dairy cattle. A decision analysis. Cornell Vet 1980; 70:247–57.
125. White ME, and Erb HN. Optimum postpartum interval for screening dairy cows for ovarian cysts by rectal palpation. Cornell Vet 1982; 72: 137–41.
126. 2α usage in a dairy reproduction program for treatment of unobserved estrus, pyometra and ovarian luteal cysts. Theriogenology 1989; 32: 693–704.
127. Wiel DFM van de, Kalis CHJ, and Nasir Hussain Shah S. Combined use of milk progesterone profiles, clinical examination and oestrus observation for the study of fertility in the post partum period of dairy cows. Bril Vet J 1979; 135: 568–77.
128. Willemsc AH, Nicuwenhuis HUR, Dieleman SJ, and Pieterse MC. Treatment of true anoestrus in dairy cows with a progesterone releasing intravaginal device (PR1D). In: ‘Factors influencing fertility in the postpartum cow’, eds Karg II, and Schallenberger E. Current topics in veterinary medicine and animal science Vol 20 Martinus Nijhoff Publishers, The Hague 1982:536–41.
129. Wohanka K. Zur Frage der sogenannten stallspezifischen Genitalinfektionen des Rindes. Monatsh Veterinärmed 1971; 26:401–7.
130. Wright PJ, and Malnto J. Pharmacologic manipulation of fertility. Vet Clin N Am-Food A 1992; 8:1,57–89.
131. Youngquist RS. Cystic follicular degeneration in the cow. In: ‘Current therapy in Theriogenology’, ed Morrow DA. WB Saunders Company, Philadelphia/London/Toronto/Mcxico City/Rio de Janeiro/Sydney/ Tokyo/Hong Kong 1986:243–6.
132. Zcddies J. Special economic aspects of fertility related to central European farming conditions. In: ‘Factors influencing fertility in the postpartum cow’, eds Karg H, and Schallcnbergcr E. Current topics in veterinary medicine and animal science Vol 20 Martinus Nijhoff Publishers, The Hague 1982:425–41.
133. Zikken A. Enkele klinische cn biochemische aspecten van hct puerperium van het rund. PhD Thesis, University of Utrecht, the Netherlands (1978).