ISSN:
0003-276X
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Medicine
Notes:
A control group of guinea pigs ovulated 3.43 ± 0.41 ova or 1.72 ova per ovary. Unilateral ovariectomy (semispaying) on day 1 resulted in the ovulation of 3.71 ± 0.37 ova from the remaining ovary, whereas after semispaying on days 5 and 10, 2.80 ± 0.12 eggs were ovaluated. Unilateral ovariectomy during days 12, 14 and just prior to ovulation resulted in the same number of ova being ovulated from the remaining ovary as from the initial ovary removed. Semispaying at any day during the cycle did not alter cycle length.At day 1, all follicles from the previous cycle were atretic. At day 5 the current population of follicles were well developed with no atresia present. Ovaries removed on days 5, 10, and 12 had approximately the same distribution of large follicles with atresia appearing in all size ranges. At day 14, the number of large follicles was markedly decreased. However, after semispaying at day 5, the remaining ovary at day 14 had twice the number of Graafian follicles and twice the amount of atresia in these size ranges as the normal day 14 ovary.It is therefore likely that the compensatory response after unilateral ovariectomy in the guinea pig is due to an increase in the rate of proliferation of smaller sized follicles into larger ones. Day 12 seems to be the critical period of the guinea pig cycle. At this time, regression of the corpora lutea occurs, and perhaps of significance, the ability of the animal to compensate for unilateral ovariectomy is also lost.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/ar.1091480207
