Effect of inbreeding on ovulation rate and foetal mortality in mice

Dissections were made of 16-day-pregnant female mice with the object of discovering the developmental stage at which litter size is reduced by inbreeding. Counts were made of the numbers of corpora lutea, implantation sites, and live embryos, and comparisons were made between females with inbreeding coefficients of 50–60% and non-inbred females. Except in one group the embryos were all non-inbred, so that the comparisons showed the effect of inbreeding in the mother of the litter. No influence of inbreeding in the male parent was found.The only difference found between inbred and non-inbred females was in the number of eggs or embryos lost before implantation. The greater pre-implantation loss in inbred females was enough to account for the smaller number of young born alive in their litters.There was no difference between the inbred and non-inbred females in the ovulation rate, measured by the number of corpora lutea, or in the post-implantation mortality of the embryos.There was a positive correlation between ovulation rate and weight at 6 weeks. For reasons explained in the Discussion, the inbred females did not differ in weight from the non-inbred females. If, under other conditions, the weight declined on inbreeding, the ovulation rate would be expected to decline also.

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Active immunization against the proregions of GDF9 or BMP15 alters ovulation rate and litter size in mice

Reproduction ◽

10.1530/rep-11-0336 ◽

2012 ◽

Vol 143 (2) ◽

pp. 195-201 ◽

Cited By ~ 20

Author(s):

C Joy McIntosh ◽

Steve Lawrence ◽

Peter Smith ◽

Jennifer L Juengel ◽

Kenneth P McNatty

Keyword(s):

Litter Size ◽

Transforming Growth Factor ◽

Transforming Growth Factor Β ◽

Cross Reactivity ◽

Full Length ◽

Ovulation Rate ◽

Corpora Lutea ◽

Immunization Group

The transforming growth factor β (TGFB) superfamily proteins bone morphogenetic protein 15 (BMP15) and growth differentiation factor 9 (GDF9), are essential for mammalian fertility. Recent in vitro evidence suggests that the proregions of mouse BMP15 and GDF9 interact with their mature proteins after secretion. In this study, we have actively immunized mice against these proregions to test the potential in vivo roles on fertility. Mice were immunized with either N- or C-terminus proregion peptides of BMP15 or GDF9, or a full-length GDF9 proregion protein, each conjugated to keyhole limpet hemocyanin (KLH). For each immunization group, ovaries were collected from ten mice for histology after immunization, while a further 20 mice were allowed to breed and litter sizes were counted. To link the ovulation and fertility data of these two experimental end points, mice were joined during the time period identified by histology as being the ovulatory period resulting in to the corpora lutea (CL) counted. Antibody titers in sera increased throughout the study period, with no cross-reactivity observed between BMP15 and GDF9 sera and antigens. Compared with KLH controls, mice immunized with the N-terminus BMP15 proregion peptide had ovaries with fewer CL (P<0.05) and produced smaller litters (P<0.05). In contrast, mice immunized with the full-length GDF9 proregion not only had more CL (P<0.01) but also had significantly smaller litter sizes (P<0.01). None of the treatments affected the number of antral follicles per ovary. These findings are consistent with the hypothesis that the proregions of BMP15 and GDF9, after secretion by the oocyte, have physiologically important roles in regulating ovulation rate and litter size in mice.

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The effect of melatonin treatment during the seasonal anoestrus on the superovulatory response and embryo production of high-prolificacy Rasa Aragonesa ewes before culling

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200012412 ◽

2003 ◽

Vol 2003 ◽

pp. 82-82

Author(s):

F. Forcada ◽

J.A. Abecia ◽

J.A. Valares

Keyword(s):

Embryonic Development ◽

Breeding Season ◽

Litter Size ◽

Direct Effect ◽

Ovulation Rate ◽

Corpora Lutea ◽

Melatonin Treatment ◽

Embryo Production ◽

Spring Equinox

The efficacy of melatonin implants inserted around the spring equinox to improve fertility and ovulation rate or litter size in Mediterranean ewes has been previously reported (Chemineau et al., 1996; Forcada et al., 2002a.), indicating the ability of the hormone to regulate the hypothalamic activity (Viguié et al., 1995). Moreover, a direct effect of melatonin on corpora lutea and embryonic development has been also reported (Wallace et al., 1988; Abecia et al., 2002). The use of prolific Rasa Aragonesa (RA) ewes (a Mediterranean breed) before culling as embryo donors has been previously tested in the breeding season (Forcada et al., 2002b.). The aim of this experiment was to improve embryo production during the seasonal anoestrus period in selected superovulated RA ewes at the end of their reproductive lives through the use of melatonin.

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Litter size components traits in two Algerian rabbit lines

World Rabbit Science ◽

10.4995/wrs.2021.14247 ◽

2021 ◽

Vol 29 (1) ◽

pp. 51

Author(s):

Rafik Belabbas ◽

Maria de la Luz García ◽

Hacina AinBaziz ◽

Ali Berbar ◽

Maria José Argente

Keyword(s):

Body Weight ◽

Litter Size ◽

Principal Components ◽

Local Population ◽

The Body ◽

Ovulation Rate ◽

Phenotypic Correlation ◽

Limiting Factor ◽

Corpora Lutea ◽

Synthetic Line

The aim of this study was to estimate the limiting litter size components in rabbit females from a Synthetic line (n=32) and a Local population (n=34). Ovulation rate, number of implanted and live embryos were counted by laparoscopy at 12 d after mating. Prolificacy (total newborn, number born alive and mortality) and embryonic, foetal and prenatal survival at day of birth of the 3rd gestation were measured. The analysed traits were body weight of the female at mating, ovulation rate, implanted, live and resorbed embryos, embryonic, foetal and prenatal survival, as well as total newborn, number born alive and mortality at birth. Synthetic line females had a higher ovulation rate compared to the Local population (11.03±0.23 vs. 8.41±0.23 corpora lutea; P<0.0001). Synthetic line displayed a higher number of implanted embryos (10.00±0.25 vs. 7.85±0.25 embryos; P<0.0001). No difference was found between groups for number of resorbed embryos. Similar embryonic, foetal and prenatal survival rates were reported between the Synthetic line and the Local population. Additionally, total newborn was higher in the Synthetic line than in the Local population (+1.46 kits; P<0.05). A principal components analysis was performed. The first four principal components (PC) explained more than 90% of the total variation in both lines. Total newborn, number born alive and live embryos were the main variables defining the 1st PC. Resorbed embryos and foetal survival were located in the 2nd PC. Ovulation rate and embryonic survival were the predominant variables defining the 3rd PC. The body weight of females was located in the 4th PC. The phenotypic correlation between total newborn and its components were high and positive in both lines, except for ovulation rate and total newborn, where it was moderate in Synthetic line. In conclusion, the females from Synthetic line have a higher total newborn than those from Local population, as a consequence of a higher number of released oocytes and embryos that successfully reach implantation. However, a higher uterine crowding in Synthetic line seems to limit survival of foetuses that reach term of gestation, while ovulation rate is the principal limiting factor of total newborn in Local population.

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A note on ovulation rate and embryonic survival in D'man ewes

Animal Science ◽

10.1017/s0003356100025071 ◽

1981 ◽

Vol 32 (2) ◽

pp. 227-229 ◽

Cited By ~ 8

Author(s):

A. Lahlou-Kassi ◽

M. Marie

Keyword(s):

Litter Size ◽

Ovulation Rate ◽

Corpora Lutea ◽

Embryonic Survival ◽

Average Litter Size ◽

Simultaneous Activity

ABSTRACTThe elements of prolificacy have been analysed for the D'man sheep, a prolific Moroccan breed, by laparotomy on 38 animals. The average ovulation rate was 2·50 (s.e.0·45); a slight difference was observed between nulliparous and multiparous ewes due to high simultaneous activity by both ovaries in the latter group. Embryonic survival (42% overall) was 94% (87 to 100%) for multiparous and 44% (36 to 52%) for the nulliparous ewes at one ovulation, decreasing with increasing numbers of corpora lutea. The average litter size showed an optimum at four ovulations.

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Ovulation and post-ovulational losses in strains of mice selected from large and small litters

Genetics Research ◽

10.1017/s0016672300010089 ◽

1966 ◽

Vol 8 (2) ◽

pp. 229-241 ◽

Cited By ~ 12

Author(s):

Nigel Bateman

Keyword(s):

Litter Size ◽

Male Fertility ◽

Ovulation Rate ◽

Foetal Mortality

This paper describes the aspects of fertility that had been affected by selection on litter size. For twelve generations previously the mice used as parents were chosen because they had been born in large or small litters. At the end of this time, litters in the fertile strain averaged 11·1 young born alive, while the less fertile strain averaged 5·5.It was found that male fertility and inherent viability of the young had nothing to do with the response although neither was excluded by the method of selection. Several contributions, however, were made by the females, who were affected not only in ovulation rate, but also in their control of pre-implantational losses, foetal mortality and mortality of the newly born.Females from the less fertile strain were particularly prone to pre-implantational loss of eggs. It remains to be shown whether these were due to fertilizational or implantational failure.The incidence of earlier and later embroyonic losses in females of the same strain were uncorrelated—Utters that were depleted early were neither more nor less inclined to be depleted later.

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Female Mice Haploinsufficient for an Inactivated Androgen Receptor (AR) Exhibit Age-Dependent Defects That Resemble the AR Null Phenotype of Dysfunctional Late Follicle Development, Ovulation, and Fertility

Endocrinology ◽

10.1210/en.2007-0248 ◽

2007 ◽

Vol 148 (8) ◽

pp. 3674-3684 ◽

Cited By ~ 90

Author(s):

K. A. Walters ◽

C. M. Allan ◽

M. Jimenez ◽

P. R. Lim ◽

R. A. Davey ◽

...

Keyword(s):

Androgen Receptor ◽

Ovarian Function ◽

Gene Dosage ◽

Early Embryo ◽

Ovulation Rate ◽

Corpora Lutea ◽

Cell Stage ◽

Gene Dosage Effect ◽

Female Mice ◽

Age Dependent

The role of classical genomic androgen receptor (AR) mediated actions in female reproductive physiology remains unclear. Female mice homozygous for an in-frame deletion of exon 3 of the Ar (AR−/−) were subfertile, exhibiting delayed production of their first litter (AR+/+ = 22 d vs. AR−/− = 61 d, P < 0.05) and producing 60% fewer pups/litter (AR+/+: 8.1 ± 0.4 vs. AR−/−: 3.2 ± 0.9, P < 0.01). Heterozygous females (AR+/−) exhibited an age-dependent 55% reduction (P < 0.01) in pups per litter, evident from 6 months of age (P < 0.05), compared with AR+/+, indicating a significant gene dosage effect on female fertility. Ovulation was defective with a significant reduction in corpora lutea numbers (48–79%, P < 0.01) in 10- to 12- and 26-wk-old AR+/− and AR−/− females and a 57% reduction in oocytes recovered from naturally mated AR−/− females (AR+/+: 9.8 ± 1.0 vs. AR−/−: 4.2 ± 1.2, P < 0.01); however, early embryo development to the two-cell stage was unaltered. The delay in first litter, reduction in natural ovulation rate, and aromatase expression in AR+/− and AR−/− ovaries, coupled with the restored ovulation rate by gonadotropin hyperstimulation in AR−/− females, suggest aberrant gonadotropin regulation. A 2.7-fold increase (AR+/+: 35.4 ± 13.4 vs. AR−/−: 93.9 ± 6.1, P < 0.01) in morphologically unhealthy antral follicles demonstrated deficiencies in late follicular development, although growing follicle populations and growth rates were unaltered. This novel model reveals that classical genomic AR action is critical for normal ovarian function, although not for follicle depletion and that haploinsufficiency for an inactivated AR may contribute to a premature reduction in female fecundity.

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Reproductive performance over repeated parities of lines of mice selected for appetite, lean growth and fatness

Animal Science ◽

10.1017/s0003356100018183 ◽

1986 ◽

Vol 42 (3) ◽

pp. 397-410 ◽

Cited By ~ 4

Author(s):

F. D. Brien ◽

W. G. Hill

Keyword(s):

Body Weight ◽

Litter Size ◽

Lean Mass ◽

Reproductive Performance ◽

Late Pregnancy ◽

Reproductive Rate ◽

Lean Growth ◽

Implantation Sites ◽

Average Total Number ◽

Post Implantation

ABSTRACTFemale reproductive performance over four parities was studied for lines of mice selected for one three criteria: appetite (A), total lean mass (P), or proportion of fat (F). Female mice were first bred 8 weeks of age, and thereafter at intervals of about 7 weeks until fourth parity when they were dissected in late pregnancy to measure components of litter size.The high A lines had higher litter sizes at the first three parities and higher ovulation rates, numbers of implantation sites and live foetuses at the fourth parity than the low A lines. The high P lines were also higher than the low P lines for each of these traits. In contrast, litter sizes and ovulation rates differed little between the high and low F lines. Fitting body weight as a covariate removed the high-low differences in ovulation rate and litter size between the P lines, but not all the differences between the A lines.Pre-implantation survival at the fourth parity was slightly lower in the high than in low A and in high than in low P lines. Differences in post-implantation survival were very small. No component of prenatal survival differed substantially at fourth parity between the high and low F lines.Differences in fertility at each parity and the percentages of females surviving to the end of the study were small. At each litter, dams of the high A lines produced heavier total weights of litters at 12 and 21 days than dams of the low A lines and the corresponding high-low differences in the P lines were larger. There were only small differences in these traits between the F lines. When litter size, fertility and survival were summed over parities, the average total number of young produced per female was substantially higher in the high than in the low A lines (5·0 young born alive or dead) and the P lines (7·2), but the high-low difference was small in the F lines (2-0). For all lines, litter size at first parity gave a reliable indication of reproductive rate during a major portion of the reproductive lifespan.

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The effects of inbreeding on the components of litter size in mice

Genetics Research ◽

10.1017/s0016672300010776 ◽

1967 ◽

Vol 10 (1) ◽

pp. 73-80 ◽

Cited By ~ 23

Author(s):

J. C. McCarthy

Keyword(s):

Litter Size ◽

Inbreeding Depression ◽

First Generation ◽

Inbreeding Coefficient ◽

Ovulation Rate ◽

Corpora Lutea ◽

Base Population ◽

Pregnant Females ◽

Sib Mating ◽

Size At Birth

Twenty-four lines were bred from a base population of outbred Q mice by continued full-sib mating. Inbreeding depression in litter size at birth was observed. This decline in litter size was analysed in terms of ovulation rate, the incidence of preimplantation mortality and the incidence of postimplantation mortality. Pregnant females were dissected at 17½ days' gestation and the numbers of corpora lutea, or eggs, and of live and dead embryos were counted. Matings were arranged so that separate estimates of the effects of inbreeding in the mother and in the litter on the components of litter size could be obtained.In the first generation of inbreeding when the inbreeding coefficient of the litter was raised from 0 to 25% decline in litter size was attributable to an increased incidence of preimplantation mortality.In the second and fourth generations decline in litter size was attributable to (1) a reduction in the number of eggs ovulated by the inbred mothers, (2) an increased incidence of preimplantation mortality which resulted from inbreeding in the mother. No evidence of significant effects on mortality of inbreeding in the litter was obtained in the later generation of inbreeding.These findings are discussed in the context of previous work on the effects of inbreeding and crossing on litter size and its components in mice and pigs.

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Pre- and peri-pubertal feed intake: effects on age at puberty and potential litter size of replacement gilts

Animal Production Science ◽

10.1071/an15871 ◽

2017 ◽

Vol 57 (6) ◽

pp. 1040

Author(s):

W. H. E. J. van Wettere ◽

M. Mitchell ◽

D. K. Revell ◽

P. E. Hughes

Keyword(s):

Litter Size ◽

Dietary Restriction ◽

Feed Intake ◽

Ovulation Rate ◽

Corpora Lutea ◽

Short Term ◽

Large White ◽

Embryo Number ◽

Age At Puberty

The effect of moderate restriction of pre- and peri-pubertal liveweight gain on puberty attainment and potential litter size was investigated. At 69 days of age, 48 Large White/Landrace crossbred gilts (28.3 ± 0.3 kg), were fed to attain a liveweight of 70 kg (LIGHT) or 100 kg (HEAVY) at 161 days of age (n = 24 gilts/treatment). At 161 days of age, half the gilts in each group were fed to gain liveweight at 0.5 (LOW) or 1.0 (HIGH) kg/day until puberty (n = 12 gilts/treatment). From 175 days of age, gilts received 20 min/day of full, physical boar contact. Gilts were artificially inseminated at the pubertal oestrus, with reproductive tracts collected 22 ± 0.1 days later, and the number of corpora lutea and viable embryos recorded. LIGHT-LOW gilts were older (P < 0.05) at puberty compared with LIGHT-HIGH, HEAVY-LOW and HEAVY-HIGH gilts; 207.7 ± 3.50 versus 191.7 ± 3.65, 193.1 ± 3.50 and 192.5 ± 3.65, respectively. Treatment (HIGH vs LOW) increased (P < 0.05) pubertal ovulation rate (15.2 ± 0.43 vs 13.1 ± 0.47), oestradiol at oestrus (13.4 ± 1.87 vs 9.1 ± 1.22 pg/mL) and progesterone 72 h post-oestrus (7.1 ± 0.48 vs 4.6 ± 0.50 ng/mL). Embryo number (10.8 ± 0.46) and survival (77.0 ± 3.21) were unaffected (P > 0.05) by treatment. To conclude, puberty was delayed by chronic, but not acute, dietary restriction. Although short-term, moderate increases in feed intake increased pubertal ovulation rates, embryo numbers and survival were unaffected.

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Reproduction in the pseudomyine rodent Mesembriomys gouldii (Gray) (Muridae)

Australian Journal of Zoology ◽

10.1071/zo9690785 ◽

1969 ◽

Vol 17 (5) ◽

pp. 785 ◽

Cited By ~ 7

Author(s):

EG Crichton

Keyword(s):

Epithelial Cells ◽

Litter Size ◽

Post Partum ◽

Oestrous Cycle ◽

Pregnant Female ◽

Corpora Lutea ◽

Limited Data ◽

Unmated Female

M. gouldii is polyoestrous and polyovular. In the non-pregnant female the oestrous cycle is 26 � 3.5 days (range 21-35 days). Mucus appears irregularly during the dioestrous interval and seems to be derived from epithelial cells of the vagina. Ovulation is spontaneous and usually alternate, one to four corpora lutea being formed. The corpora lutea of the unmated female are functional until the 15th-17th day of the cycle. Gestation lasted from 43 to 44 days, a "placental sign" occurring between the 22nd and 33rd day. A post-partum oestrus and mating occur but no delay in implantation was recorded. Litter size ranges from one to three. The young are well developed at birth, and cling tenaciously to the teats for the first few weeks. Growth is rapid and the young can be weaned after 42 days. This pattern of reproduction is compared with the limited data from other Australian Muridae.

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