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Influence of lurogestone acetate on serum progesterone and histological characteristics in ewes

Published online by Cambridge University Press:  02 September 2010

H. M. Schoenemann  and
D. M. Hallford
H. M. Schoenemann
Affiliation:
Department of Animal and Range Sciences, New Mexico State University, Las Cruces, New Mexico 88003, USA
D. M. Hallford
Affiliation:
Department of Animal and Range Sciences, New Mexico State University, Las Cruces, New Mexico 88003, USA
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Abstract

At the beginning of the autumn breeding season, six Rambouillet ewes were treated with intravaginal pessaries containing 20 mg flurogestone acetate on day 10 (oestrus = day 0) of an oestrous cycle. Sponges were removed after 12 days. Five additional ewes served as untreated controls. Vasectomized rams were used twice daily to detect oestrus and blood samples were collected daily from day 1 until 3 days following the post-treatment oestrus. Animals were slaughtered and reproductive tracts were recovered 3 days after the oestrus followingpessary removal. Epithelial, endometrial and glandular measurements were recorded from sections of oviduct, uterus and cervix using a refrigerated microtome. Serum progesterone was quantified by radioimmunoassay. Intravaginal progestagen treatment prevented ewes from exhibiting oestrus during the period in which pessaries were in place. Oestrus was observed, however, in all treated animals within 2 days of sponge removal, resulting in a mean cycle length (±.e.) of 23·2 (±0·2) days compared with 17·6 (±0·2) days (P<0·01) for controls. Serum progesterone profiles in treated and control animals indicated that corpora lutea regression progressed normally in ewes receiving the exogenous progestagen. Neither reproductive tract weight, ovarian weight, ovulation rate nor follicle number differed between groups (P>0·10). Oviductal, uterine, uterine glandular and cervical epithelial cell heights, as well as uterine glandular proliferation and endometrial thickness, were also similar in treated and control ewes (P>0·10). These data suggest that intravaginal flurogestone acetate does not appreciably alter histology of the reproductive tract during the time in which the fertilized ova would enter the uterus. Overt histological changes, therefore, are not likely to be a significant cause of reduced fertility at a synchronized oestrus.

Type
Research Article
Information
Animal Production , Volume 35 , Issue 3 , December 1982 , pp. 321 - 326
Copyright
Copyright © British Society of Animal Science 1982

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References

REFERENCES

Baird, D. T., Land, R. B., Scaramuzzi, R. J. and Wheeler, A. G. 1976. Endocrine changes associated with luteal regression in the ewe; the secretion of ovarian oestradiol, progesterone and androstenedione and uterine prostaglandin F2α throughout the oestrous cycle. J. Endocr. 69: 275–286.CrossRefGoogle ScholarPubMed
Bancroft, J. D. 1977. Frozen and related sections. In Theory and Practice of Histological Technique (ed. Bancroft, J. and Stevens, A.), pp. 65–69. Churchill Livingstone, New York.Google Scholar
Casjda, L. E. and McKenzie, F. F. 1932. The oestrous cycle of the ewe: histology of the genital tract. Bull. Mo. agric. Exp. Stn, No. 170.Google Scholar
Cumming, I. A., Buckmaster, J. M., Blockey, M. A. DeB., Goding, J. R., Winfield, C. G. and Baxter, R. W. 1973. Constancy of interval between luteinizing hormone release and ovulation in the ewe. Biol. Reprod. 9: 24–29.CrossRefGoogle ScholarPubMed
Deweese, W. P., Gump, H. A. and Dutt, R. H. 1970. Comparison of medroxyprogesterone acetate orally and in vaginal sponges for synchronizing estrus in ewes. J. Anim. Sci. 31: 394–397.CrossRefGoogle ScholarPubMed
Echternkamp, S. E., Bolt, D. J. and Hawk, H. W. 1976. Ovarian and pituitary hormones in blood of progestogen-treated ewes. J. Anim. Sci. 42: 893–900.CrossRefGoogle ScholarPubMed
Gibori, G., Antczak, E. and Rothchild, I. 1977. The role of estrogen in the regulation of luteal progesterone ?ecretion in the rat after day 12 of pregnancy. Endocrinology 100: 1483–1495.CrossRefGoogle Scholar
Gill, J. L. and Hafs, H. D. 1971. Analysis of repeated measurements of animals. J. Anim. Sci. 33: 331–336.CrossRefGoogle ScholarPubMed
Haresign, W. 1978. Ovulation control in the sheep. In Control of Ovulation (ed. Crighton, D., Haynes, N., Foxcroft, G. and Lamming, G.), pp. 435–451. Butterworth, London.CrossRefGoogle Scholar
Hawk, H. W. 1975. Hormonal control of changes in the direction of uterine contractions in the estrous ewe. Biol. Reprod. 12: 423–430.CrossRefGoogle ScholarPubMed
Hawk, H. W. and Conley, H. H. 1973. Route of progestagen administration to the ewe and spermicidal action in the vagina at the ensuing estrus. J. Anim. Sci. 37: 957–961.CrossRefGoogle Scholar
Hawk, H. W. and Cooper, B. S. 1975. Improvement of sperm transport by the administration of estradiol to estrous ewes. J. Anim. Sci. 41: 1400–1406.CrossRefGoogle ScholarPubMed
Hawk, H. W. and Cooper, B. S. 1977. Sperm transport into the cervix of the ewe after regulation of estrus with prostaglandin or progestagen. J. Anim. Sci. 44: 638–644.CrossRefGoogle ScholarPubMed
Hoermann, A. L. and Sorensen, A. M. Jr 1970. Histology of the synchronized ewe. J. Anim. Sci. 30: 321(Abstr.).Google Scholar
Inskeep, E. K., Stevens, L. P. and Rudy, C. R. 1979. Fertility in ewes receiving low doses of estradiol during synchronized estrus. J. Anim. Sci. 48: 52–53.CrossRefGoogle ScholarPubMed
Kittok, R. J., Britt, J. H. and Convey, E. M. 1973. Endocrine response after GnRH in luteal phase cows and cows with ovarian follicular cysts. J. Anim. Sci. 37: 985–989.CrossRefGoogle ScholarPubMed
Langford, G. A., Marcus, G. J., Hackett, A. J., Ainsworth, L. and Wolynetz, M. S. 1980. Influence of estradiol- 17β on fertility in confined sheep inseminated with frozen semen. J. Anim. Sci. 51: 911–916.CrossRefGoogle ScholarPubMed
Lintin, K. and Lamming, G. E. 1973. The effects of progestagens and PMSG on peripheral plasma LH levels in the Clun Forest ewe. J. Reprod. Fert. 35: 607–609.CrossRefGoogle ScholarPubMed
Quinltvan, T. D. and Robinson, T. J. 1969. Numbers of spermatozoa in the genital tract after artificial insemination of progestagen-treated ewes. J. Reprod. Fert. 19: 73–86.CrossRefGoogle Scholar
Ruttle, J. L. and Menzies, J. M. 1975. Reproductive performance of ewes treated with intravaginal progestin. Bull. New Mex. agric. Exp. Sin, No. 630.Google Scholar
Snedecor, G. W. and Cochran, W. G. 1967. Statistical Methods. 6th ed. Iowa State University Press, Ames, la.Google Scholar
Stabenfeldt, G. H., Holt, J. A. and Ewing, L. L. 1969. Peripheral plasma progesterone levels during the ovine estrous cycle. Endocrinology 85: 11–15.CrossRefGoogle ScholarPubMed
Swanson, L. V., Hafs, H. D. and Morrow, D. A. 1972. Ovarian characteristics and serum LH, prolactin, progesterone and glucocorticoid from first estrus to breeding size in Holstein heifers. J. Anim. Sci. 34: 284–293.CrossRefGoogle ScholarPubMed
Thorburn, G. D., Bassett, J. M. and Smith, I. D. 1969. Progesterone concentration in the peripheral plasma of sheep during the oestrous cycle. J. Endocr. 45: 459–469.CrossRefGoogle ScholarPubMed