Impact of superovulation and mating on the wellbeing of juvenile and adult C57BL/6N mice (original) (raw)
Related papers
Impaired fertility in T-stock female mice after superovulation
Reproduction, 2004
Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice.In vivomatings of superovulated T-stock females with B6C3F1 males resulted in a two-fold reduction (P< 0.001) in the frequencies of fertilized eggs compared with control B6C3F1 matings. In addition, approximately 22 h after mating, only 15% of fertilized eggs recovered in T-stock females had reached the metaphase stage of the first cleavage division versus 87% in B6C3F1 females (P< 0.0001). Matings with T-stock males did not improve the reproductive performance of T-stock females. To investigate the possible cause(s) for the impaired fertilization and zygotic development, the experiments were repeated usingin vitrofertilization. Under these conditions, the frequencies of fertilized eggs were not different in superovulated T-stock a...
REPRODUCTIONRESEA CH Impaired fertility in T-stock female mice after superovulation
2015
Superovulation of female mice with exogenous gonadotrophins is routinely used for increasing the number of eggs ovulated by each female in reproductive and developmental studies. We report an unusual effect of superovulation on fertilization in mice. In vivo matings of superovulated T-stock females with B6C3F1 males resulted in a two-fold reduction (P < 0.001) in the frequencies of fertilized eggs compared with control B6C3F1 matings. In addition, approximately 22 h after mating, only 15% of fertilized eggs recovered in T-stock females had reached the metaphase stage of the first cleavage division versus 87 % in B6C3F1 females (P < 0.0001). Matings with T-stock males did not improve the reproductive performance of T-stock females. To investigate the possible cause(s) for the impaired fertilization and zygotic development, the experiments were repeated using in vitro fertilization. Under these conditions, the frequencies of fertilized eggs were not different in superovulated T-...
Effects of prenatal stress on reproduction in male and female mice
Physiology & Behavior, 1984
POLITCH, J. A. AND L. R. HERRENKOHL. Effects of prenatal stress on reproduction in male and female mice. PHYSIOL BEHAV 32(1) 95-99, 1984.--Pregnant mice were exposed to heat-restraint stress from Days 14 through 21 of gestation. Feminine receptivity quotients were significantly higher in prenatally-stressed male offspring than in unhandled males; however there were no differences in testes weights or masculine copulatory behavior. Prenatally stressed females exhibited vaginal opening at a later date, had longer estrus cycles and higher median quality receptivity scores than unhandled controls. Prenatal stress had no profound effects on pregnancy, parturition or survival of young. However there was a significantly smaller proportion of parturient postnatally stressed females compared to unhandled controls.
Efficient Superovulation and Egg Collection from Mice
BIO-PROTOCOL
Superovulation is a method used to reduce the number of mice used per experiment by increasing the egg number. Conventionally, superovulation for obtaining mouse eggs involves the use of equine chorionic gonadotropin (eCG) for stimulation and human CG for induction. Female mice of the C57BL/6 inbred strain spontaneously ovulate approximately 10 eggs. The average number of eggs ovulated using the conventional superovulation method is approximately twice as high as that obtained by spontaneous ovulation. Here, we describe the conventional and non-conventional methods of intraperitoneal injection of superovulation reagents in mice and subsequent egg collection. The nonconventional superovulation method combining anti-inhibin serum (AIS) plus eCG for stimulation is more efficient than conventional superovulation. Appropriate intervals from each injection to sampling induce large numbers of high-quality eggs. Immediately after ovulation, eggs are surrounded by cumulus cells, forming an egg-cumulus complex. These cumulus cells are then removed from the egg-cumulus complex by treatment with hyaluronidase to obtain the exact number of eggs. This protocol is suitable for further manipulations such as intracytoplasmic sperm injection and cryopreservation of eggs, as well as for the analyses of responsivity to superovulation reagents in genetically modified mice obtained by genome editing.
Theriogenology, 2008
Mouse oocytes can be obtained via superovulation or using in vitro maturation although several factors, including genetic background, may affect response. Our previous studies have identified various mouse species as models to understand the role of sexual selection on the evolution of sperm traits and function. In order to do comparative studies of sperm-oocyte interaction, we sought reliable methods for oocyte superovulation and in vitro maturation in mature females of three mouse species (genus Mus). When 5 IU pregnant mare's serum gonadotrophin (PMSG) and 5 IU human chorionic gonadotrophin (hCG) were injected 48 h apart, and oocytes collected 14 h post-hCG, good responses were obtained in Mus musculus (18 AE 1.3 oocytes/female; mean AE S.E.M.) and Mus spretus (12 AE 0.8), but no ovulation was seen in Mus spicilegus. Changes in PMSG or hCG doses, or longer post-hCG intervals, did not improve results. Use of PMSG/luteinizing hormone (LH) resulted in good responses in M. musculus (19 AE 1.2) and M. spretus (12 AE 1.1) but not in M. spicilegus (5 AE 0.9) with ovulation not increasing with higher LH doses. Follicular puncture 48 h after PMSG followed by in vitro maturation led to a high oocyte yield in the three species (M. musculus, 23 AE 0.9; M. spretus, 17 AE 1.1; M. spicilegus, 10 AE 0.9) with a consistently high maturation rates. In vitro fertilization of both superovulated and in vitro matured oocytes resulted in a high proportion of fertilization (range: 83-87%) in the three species. Thus, in vitro maturation led to high yields in all three species. These results will allow future studies on gamete interaction in these closely related species and the role of sexual selection in gamete compatibility. #
Laboratory Animals, 2020
For a wide range of biomedical approaches, an accurate estimate of the age of embryos or pups is important. Overnight mating is the method that is mostly used to establish timed pregnancies. The oestrus cycle in mice repeats every four to five days. So, not all females will get pregnant because they are not in oestrus. Therefore, the aim of this study was to analyse whether polygamous mating could increase the rate of timed pregnancies per breeding cage and female. We compared overnight timed mating regimes with up to four females per male, using C57BL/6 and BALB/c mice as well as F1 hybrids of these two strains. The number of vaginal plugs, number of females that gave birth and weaned litter (including size and weaning weight) were recorded. Our results showed that the plug and pregnancy rate decreased, but the productivity per breeding cage increased for polygamous mating regimes. The proportion of females with vaginal plugs and females that gave birth was significantly higher in ...
Animal Models and Experimental Research in Medicine [Working Title]
In most research involving female reproductive function, female animals particularly mice and rats are usually employed. This may perhaps be due to their well-defined reproductive cycle (estrous cycle) as well as the ability to breed and handle them easily. The short and precise length of estrus cycle usually 4–5 days make mice models the choicest mammal when it comes to human related research. Also, they possess very short reproductive age typically 7–8 months reaching sexual maturity at weeks 4–7 following their birth. Although many similarities exist between this model and humans, however, there also exist obvious distinctions between the human female reproductive system and that of mice. Humans have average length of their reproductive or menstrual cycle of about 28–29 days with their reproductive ages between 10–40 years. These relevant differences between mice and human reproductive system constitute the limitations to the use of this models. Therefore, the scope of this chapt...
Superovulation of female mice delays embryonic and fetal development
Human Reproduction, 2001
This delay can be caused by suboptimal culture conditions, but possible influences of ovarian stimulation cannot be excluded. The objective of this study was to test the hypothesis that both in vitro and in vivo, preimplantation embryonic development and postimplantation fetal development are impaired in superovulated female mice when compared with naturally cycling controls. A delay in in-vitro blastocyst hatching and in-vivo blastocyst formation (P < 0.03 and P < 0.0001 respectively) and a 40% fetal growth retardation (P < 0.0001) were observed after superovulation in comparison with naturally cycling controls. After transfer to non-stimulated foster mothers, blastocysts from stimulated females had a lower implantation rate (P < 0.005), and developed into fewer living fetuses (P < 0.02), more resorption sites (P < 0.02) and had more pronounced growth retardation (P < 0.0001) when compared with blastocysts from naturally cycling controls. In conclusion, superovulation in the mouse causes a delayed embryonic development in vitro and in vivo, an increased abnormal blastocyst formation, a pronounced fetal growth retardation, and an increased number of resorption sites. If this observation in mice can be extrapolated to humans, it may offer an explanation for the delay in embryonic development and the low birth weight observed after IVF.
Journal of assisted reproduction and genetics, 1999
This study was conducted to determine whether the omission of spermiogenesis and all prefertilization events for five generations in mice affects the fertility or behavior of offspring. Fifth-generation hybrid (C57BL/6 x DBA/2) mice were produced using round spermatid injection (ROSI). Control groups consisted of mice born after natural mating with and without sham operation. The growth, fertility, and behavior of offspring were compared. Behavior tests conducted assessed elementary reasoning (Krushinsky test), emotionality (Mouse Defense Test Battery), and spatial learning and memory (Morris water maze). There were no significant differences in the growth and fertility of fifth-generation ROSI mice compared to natural fertilization mice. We also found no evidence of significant learning or behavioral deficits of the fifth-generation ROSI mice. In this study, we found no evidence that bypassing the natural biological processes involved in spermiogenesis produces adverse effects on t...
Mice selected for age of puberty: reverse selection and reproductive characteristics
Biology of Reproduction, 1983
Previous investigations have hypothesized a link between regulation of population size in various rodent species and changes in allele frequencies for certain loci that exert their effects on particular behaviors or processes related to reproduction. Drickamer (1981a) has shown that age of first vaginal estrus can be shifted by artificial selection and that there is a relatively high heritability for this trait in laboratory Mus. This paper reports on two related experiments, one a test of reverse selection on strains of mice previously selected for early and late first vaginal estrus, and the other a compilation of data for a variety of traits related to reproduction for the original base stock and four artificially selected stocks. The original selection for early and late onset of puberty did not result in fixation of the trait-enough residual variation remained so that in eight generations of selection it was possible to significantly reverse the timing of first estrus. Traits related to reproduction including litter size, pup weight, survival of pups to 21 days, weight at 21 days, fertility and birth intervals all were not affected by the selection process across all five stocks tested. These results are discussed with regard to changes in puberty and generation time in Mus as a factor in population regulation.