Oestrogens in Faeces as an Indicator of the Foeto-Placental Unit Function in Mares

Abstract

Total of 30 pregnant mares were used in this study: 17 Thoroughbred and 13 Primitive Polish Horse. The concentration of total unconjugated oestrogens was determined by radioimmunoassay in faecal samples obtained every second week after mating until delivery or interruption of pregnancy. Concentration of oestrogens in pregnant healthy mares ranged from 40 to 200 ng/g and showed typical profiles for pregnancy. In 5 of 30 mares (16.6%) of either breed abortions and cases of embryonic death occurred. Abortions were preceded by sharp or gradual decrease in oestrogen concentration, whereas prior to embryonic death no elevation of the level of these hormones was noted. The present data suggest that determination of faecal oestrogens may serve as an indicator of the foeto-placental unit function during either the physiological or pathological pregnancy.

Key words

oestrogen - faeces - foeto-placental unit - gestation - horse

References

• 1 Allen WR. Fetomaternal interactions by endocrine organs during equine pregnancy.  Reprod. 2001;  121 513-527
• 2 Bamberg E, Choi HS, Möstl E, Wurm W, Lorin D, Arbeiter K. Enzymatic determination of unconjugated oestrogens in faeces for pregnancy diagnosis in mares.  Equ Vet J. 1984;  16 537-539
• 3 Cox JE. Estrone and equilin in plasma of pregnant mare.  J Reprod Fert. 1975;  23 ((suppl.)) 463-468
• 4 Daels PF, Shideler S, Lasley BL, Hyghes JP, Stabenfeldt GH. Source of oestrogens in early pregnancy in the mare.  J Reprod Fert. 1990;  90 55-61
• 5 Darenius K, Kindahl H, Knudsen O, Madej A, Edqvist LE. PMSG, progesterone and oestrone sulphate during normal pregnancy and early fetal death.  J Reprod Fert. 1983;  32 ((suppl)) 625-626
• 6 Darenius K, Kindahl H, Madej A. Clinical and endocrine aspects of early foetal death in the mare.  J Reprod Fert. 1988;  35 ((suppl)) 497-498
• 7 Henderson KM, Perkins NR, Wards RL, Stewart JI. Non-invasive pregnancy determination in mares by enzymeimmunoassay of oestrone sulphate concentration in faeces.  Proceed NZ Soc Anim Prod. 1997;  57 234
• 8 Henderson K, Stevens S, Bailey C, Hall G, Stewart J, Wards R. Comparison of the merits of measuring equine chorionic gonadotrophin (eCG) and blood and faecal concentrations of oestrone sulphate for determining the pregnancy status of miniature horses.  Reprod Fert Dev. 1998;  10 441-444
• 9 Hoffmann B, Gentz F, Failing K. Investigations into the course of progesterone-, oestrogen- and eCG-concentrations during normal and impaired pregnancy in the mare.  Reprod Dom Anim. 1996;  31 717-723
• 10 Hoffmann B, Leiser R, Schuler G. Physiologie und Anatomie der Trächtigkeit, Trächtigkeitsdiagnostik. In: Aurich Ch, ed. Reproduktionsmedizin beim Pferd. Stuttgart: Parey Verlag 2005: 125-154
• 11 Hyland JH, Wright PJ, Manning SJ. An investigation of the use of plasma oestrone sulphate concentrations for the diagnosis of pregnancy in mares.  Australian Vet J. 1984;  61 123-124
• 12 Kasman LH, Hughes JP, Stabenfeldt GH, Starr MD, Lasley BL. Estrone sulfate concentrations as an indicator of fetal demise in horses.  Am J Vet Med Res. 1988;  49 184-187
• 13 Kirckpatrick F, Shideler SE, Turner JW. Pregnancy determination in uncapured feral horses based on steroid metabolites in urine-soaked snow and free steroids in feces.  Can J Zool. 1990;  68 2576-2579
• 14 Kindahl H, Knudsen O, Madej A, Edqvist LE. Progesterone, prostaglandin F₂α, PMSG and oestrone sulfate during early pregnancy in the mare.  J Reprod Fert. 1982;  32 ((suppl)) 353-359
• 15 Kuckelkorn B. Assessment of pregnancy in kiang mares (Equus hemionus holdereri) using estrogen determination in faeces.  Theriogenology. 1994;  42 37-41
• 16 Lucas Z, Raeside JI, Rossdale PD, Rowlands IW. Non-invasive assessment of the incidences of pregnancy and pregnancy loss in feral horses of Sable Island.  Proceed 5th Intern Symp Equine Reprod. 1991;  479-488
• 17 Möstl E. The horse feto-placental unit.  Exp Clin Endocrinol. 1994;  102 166-168
• 18 Möstl E, Nobauer H, Choi HS, Wurm W, Bamberg E. Trächtigkeitsdiagnose bei der Stute mittels Östrogenbestimmung im Kot.  Prakt Tierarzt. 1983;  64 491-492
• 19 Ousey JC. Peripartal endocrinology in the mare and fetus.  Reprod Dom Anim. 2004;  39 222-231
• 20 Palme R, Entenfellner U, Choi H, Möstl E. Faecal oestrogens and progesterone metabolites in mares of different breeds during the last trimester of pregnancy.  Reprod Dom Anim. 2001;  36 273-277
• 21 Parkes RD, Blackmore DJ, Rance TA. Plasma concentrations of equilin and estrone in assessment of fetoplacental function in mare.  Vet Rec. 1977;  100 511-512
• 22 Pashen RL, Allen WR. The role of fetal gonads and placenta in steroid production, maintenance of pregnancy, and parturition in the mare.  J Reprod Fert. 1979a;  27 ((suppl)) 499-509
• 23 Pashen RL, Allen WR. Endocrine changes after foetal gonadectomy and during normal and induced parturition in the mare.  Anim Reprod Sci. 1979b;  2 271-288
• 24 Schwarzenberg F, Möstl E, Palme R, Bamber E. Faecal steroid analysis for non-invasive monitoring of reproductive status in farm, wild and zoo animals.  Anim Reprod Sci. 1996;  42 515-526
• 25 Skolimowska A, Janowski T, Golonka M. Estrogen concentration in the feces and blood of full-blood and Polish Horse mares during pregnancy (in polish).  Medycyna Wet. 2004a;  60 96-99
• 26 Skolimowska A, Janowski T, Krause I, Golonka M. Monitoring of pregnancy be fecal estrogen measurement in sanctuary and zoological Equide (in polish).  Medycyna Wet. 2004b;  60 857-860
• 27 Terqui M, Palmer E. Oestrogen pattern during early pregnancy in the mare.  J Reprod Fert. 1979;  27 ((suppl)) 441-446

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