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The effects of dietary urea on embryo development in superovulated donor ewes and on early embryo survival and development in recipient ewes

Published online by Cambridge University Press:  18 August 2016

J. Fahey ,
M.P. Boland  and
D. O’Callaghan1
J. Fahey
Affiliation:
Faculty of Veterinary Medicine, University College Dublin, Ireland
M.P. Boland
Affiliation:
Faculty of Agriculture, University College Dublin, Ireland Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland
D. O’Callaghan1*
Affiliation:
Faculty of Veterinary Medicine, University College Dublin, Ireland Conway Institute of Biomolecular and Biomedical Research, University College Dublin, Ireland
*
†Corresponding author; address to Faculty of Veterinary Medicine.
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Abstract

The aim was to examine the effect of dietary urea on yield and quality of embryos in superovulated donor ewes, and on embryo survival in recipient ewes. Ewes (25 donors and 34 recipients) were offered 1·25 kg of grass meal containing 50 g urea per ewe per day on a group basis; the remaining ewes (30 donors and 32 recipients) received 1·25 kg untreated grass meal per day. After 5 days, ewes were synchronized using a progestagen pessary for 14 days and stimulated with pregnant mare serum gonadotropin. Donors were naturally mated; recipients were detected in oestrus using vasectomized rams. On day 4 following the onset of oestrus, embryos were recovered from donors, graded morphologically and cell number counted. Two embryos of acceptable morphological grade (≥ eight cells on day 4) were then surgically transferred to recipient ewes. Recipients were slaughtered between days 34 and 36 post oestrus. The mean number of embryos recovered per ewe [3·68 (s.e. 0·41) v. 3·83 (s.e. 0·45)] was not different between untreated and urea-treated ewes, respectively. However, urea treatment of donor ewes reduced the mean cell number per embryo (10·27 (s.e. 0·27) v. 8·17 (s.e. 0·29) for untreated and urea-treated donor ewes, respectively, P < 0·001). Similarly, the percentage of embryos recovered that had ≥ 10 cells and their mean cell number was reduced following urea treatment of donor ewes (82/113 (73%) v. 39/93 (42%), P < 0·01 and 11·61 (s.e. 0·20) v. 10·41 (s.e. 0·29), P < 0·001) for untreated and urea-treated ewes, respectively. The diet offered to recipient ewes had no effect on the number of ewes confirmed pregnant (24/32 (75%) v. 28/34 (82%)) or on embryo survival following transfer (45/64 (70%) v. 51/68 (75%) for untreated and urea-treated ewes, respectively, P > 0·05). Excess nonprotein nitrogen in the form of dietary urea reduced embryo quality. However, embryo survival in recipient ewes was not affected when good quality embryos were transferred. This suggests that the deleterious effects of excess dietary urea are due to alterations to the oocyte and (or) the oviductal environment rather than changes in the uterine environment.

Keywords

embryosewessuperovulationurea.
Type
Reproduction
Information
Animal Science , Volume 72 , Issue 2 , April 2001 , pp. 395 - 400
Copyright
Copyright © British Society of Animal Science 2001

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References

Bishonga, C., Robinson, J. J., McEvoy, T. G., Aitken, R. P., Findlay, P. A. and Robertson, I. 1994. The effects of excess rumen degradable protein in ewes on ovulation rate, fertilization and embryo survival in vivo and during in vitro culture. Animal Production 58: 447 (abstr. ).Google Scholar
Bishonga, C., Robinson, J. J., McEvoy, T. G., Findlay, P., Aitken, R. P. and Robertson, I. 1996. Excess dietary urea intake in ewes and its effects on ovulation rate and embryo development. Japanese Journal of Veterinary Research 44: 139–151.Google ScholarPubMed
Blanchard, T., Ferguson, J., Love, L., Takeda, T., Henderson, B., Hasler, J. and Chalupa, W. 1990. Effect of dietary crude-protein type on fertilization and embryo quality in dairy cattle. American Journal of Veterinary Research 51: 905–908.CrossRefGoogle ScholarPubMed
Boland, M. P., Crosby, T. F. and Gordon, I. 1983. Ovarian response in ewes following horse anterior pituitary extract and progestagen treatment. Animal Reproduction Science 6: 119–127.CrossRefGoogle Scholar
Butler, W. R., Calaman, J. J. and Beam, S. W. 1996. Plasma and milk urea nitrogen in relation to pregnancy rate in lactating dairy cattle. Journal of Animal Science 74: 858–865.CrossRefGoogle ScholarPubMed
Canfield, R. W., Sniffen, C. J. and Butler, W. R. 1990. Effects of excess degradable protein on postpartum reproduction and energy balance in dairy cattle. Journal of Dairy Science 73: 2342–2349.CrossRefGoogle ScholarPubMed
Elrod, C. C. 1992. High dietary protein and high fertility can we have both? In Proceedings of the 1992 Cornell nutrition conference for feed manufacturers, pp. 32–39. Cornell University, Ithaca, New York.Google Scholar
Elrod, C. C. and Butler, W. R. 1993. Reduction of fertility and alteration of uterine pH in heifers fed excess ruminally degradable protein. Journal of Animal Science 71: 694–701.Google Scholar
Folman, Y., Neumark, H., Kaim, M. and Kaufmann, W. 1981. Performance, rumen and blood metabolites in high-yielding cows fed varying protein percents and protected soyabean. Journal of Dairy Science 64: 759–768.Google Scholar
Garcia-Bojalil, C.M., Staples, C. R., Thatcher, W. W. and Drost, M. 1994. Protein intake and development of ovarian follicles and embryos of superovulated nonlactating dairy cows. Journal of Dairy Science 77: 2537–2548.CrossRefGoogle ScholarPubMed
Gath, V., Lonergan, P., Boland, M. P. and O’Callaghan, D. 1999. Effects of diet type on establishment of pregnancy and embryo development in beef heifers. Proceedings of the 25th Irish Grassland and Animal Production Association, 25-26 March, pp. 97–98.Google Scholar
Grings, E. E., Roffler, R. E. and Deitelhoff, D. P. 1991. Response of dairy cows in early lactation to additions of cottonseed meal in alfalfa-based diets. Journal of Dairy Science 74: 2580–2587.Google Scholar
Jordan, E. R., Chapman, T. E., Holtan, D. W. and Swanson, L. V. 1983. Relationship of dietary crude protein to composition of uterine secretions and blood in high-producing postpartum dairy cows. Journal of Dairy Science 66: 1854–1862.Google Scholar
Jordan, E. R. and Swanson, L. V. 1979. Effect of crude protein on reproductive efficiency, serum total protein, and albumin in the high-producing dairy cow. Journal of Dairy Science 62: 58–63.CrossRefGoogle Scholar
Kennedy, L. G., Boland, M. P. and Gordon, I. 1983. The effect of embryo quality at freezing on subsequent development of thawed cow embryos. Theriogenology 19: 823–832.Google Scholar
Kenny, D. A., Boland, M. P., Diskin, M. G. and Sreenan, J. M. 1999. The effect of crude protein and fermentable carbohydrate intake on blood metabolite concentrations and fertility in cattle grazing spring pasture. Proceedings of the 25th Irish Grassland and Animal Production Association, 25-26 March, pp. 95–96.Google Scholar
Lane, M. and Gardner, D. K. 1994. Increase in postimplantation development of cultured mouse embryos by amino acids and induction of fetal retardation and exencephaly by ammonium ions. Journal of Reproduction and Fertility 102: 305–312.Google Scholar
McEvoy, T. G., Robinson, J. J., Aitken, R. P., Findlay, P. A. and Robertson, I. S. 1997. Dietary excesses of urea influence the viability and metabolism of preimplantation sheep embryos and may affect fetal growth among survivors. Animal Reproduction Science 47: 71–90.Google Scholar
Sonderman, J. P. and Larson, L. L. 1989. Effect of dietary protein and exogenous gonadotropin-releasing hormone on circulating progesterone concentrations and performance of Holstein cows. Journal of Dairy Science 72: 2179–2183.Google Scholar
Systat. 1990. Systat version 5·03. Systat Inc., IL, USA.Google Scholar