אסיף מאגר המחקר החקלאי

Ontogeny of ovarian follicle development in Booroola sheep fetuses that are homozygous carriers or non-carriers of the Fec(B) gene

Year:

1994

Source of publication :

Authors :

Volume :

100

Co-Authors:

Smith, P., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand
Braw-Tal, R., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand
Corrigan, K., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand
Hudson, N.L., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand
Heath, D.A., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand
McNatty, K.P., Wallaceville Animal Research Centre, PO Box 40063, Upper Hutt, New Zealand

Facilitators :

Link :

Abstract:

The aims of this study were to examine the effects of the Booroola Fec(B) gene on ovarian development and reproductive hormones (FSH, LH and inhibin) at days 90, 100, 120 and 135 of gestation (term = 147 days). The effects of litter size were eliminated by transferring equal numbers of homozygous BB and control (++) embryos to recipient ewes. The ovary, but not the body, pituitary, adrenal, kidney or thymus, was heavier (P < 0.05) in BB compared with ++ fetuses at day 90 but not thereafter. In the ovary, gene-specific differences were observed in the total number of germ cells present at days 90 (P < 0.01) and 135 (P < 0.05) with the same tendency being noted at day 100 (P < 0.07); at all of these ages the mean numbers of germ cells in the BB genotype exceeded those in ++ animals. Gene-specific differences were observed in the numbers of oogonia and isolated oocytes at day 90 (i.e. BB > ++), in the number of primordial follicles at days 100 (BB > ++) and 135 (BB > ++), and also in the number of primary or secondary follicles (++ > BB) at day 135. At each gestational age examined no differences were noted with respect to the plasma concentrations of FSH, LH or inhibin between the BB and ++ fetuses. However, the highest mean plasma concentrations of FSH and LH occurred at days 90 and 100 of gestation, which coincided with the first developing primary follicles. Collectively, the results from this and previous studies show that the different effects of the Fec(B) gene in germ cell development in early gestation continue throughout fetal development independently of litter size. Moreover, during the growth of the first primary and secondary follicles at days 100 and 120, respectively, there are no differences in the plasma concentrations of FSH, LH and inhibin with respect to Booroola genotype.

Note:

Related Files :

Related Content

More details

You may also be interested in