Fertility in Cheviot ewes. 3. The effect of level of nutrition before and after mating on ovulation rate and early embryo mortality in South Country Cheviot ewes in moderate condition at mating

1979 ◽  
Vol 29 (1) ◽  
pp. 25-31 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney ◽  
W. F. Smith
Keyword(s):  
Food Intake ◽  
Body Condition ◽  
Good Condition ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Embryo Mortality ◽  
Low Level ◽  
Moderate Condition ◽  
High Level

ABSTRACTOne hundred and twenty South Country Cheviot hill ewes were differentially group-fed indoors over a 2-month period to achieve either moderately-good or poor body condition. Over 5 weeks prior to mating, ewes in moderately-good condition were brought down in condition by restricted feeding and ewes in poor body condition were raised in condition by a high level of feeding. The ewes were thus in moderate condition at mating. During the first 4 weeks after mating, half the ewes from each original condition group were fed at a high level and the other half were fed at a low level. Ewes were killed either on return to service or at 30 ± 10 days forcounts of corpora lutea and viable embryos.Ovulation rate was not significantly related to the level of pre-mating food intake at the condition level studied, although the trend was positive. Embryo mortality, as ova loss, was reduced by a high level of post-mating food intake but was increased by a high level of pre-mating intake. This latter result, however, may be influenced by the experimental confounding of high pre-mating food intake and very low initial body condition. The greatest loss was incurred by ewes, originally in poor condition, which were fed at a high pre-mating level and a low post-mating level. Potential lambing rate at slaughter was not affected by the level of food intake either before or after mating although the trend was for a low level of post-mating intake to be associated with an increase in the proportion of barren ewes.

The interaction of nutrition and body condition at mating on ovulation rate and early embryo mortality in Scottish Blackface ewes

1975 ◽  
Vol 85 (3) ◽  
pp. 465-470 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney
Keyword(s):  
Food Intake ◽  
Body Condition ◽  
Good Condition ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Service Rate ◽  
Corpora Lutea ◽  
Embryo Mortality ◽  
Poor Condition ◽  
High Level

SUMMARYOne hundred and fifty-six Scottish Blackface ewes were differentially group-fed over a 2-month period to achieve three distinct levels of body condition (good, moderate and very poor). Over 5 weeks prior to mating, one group of good-condition ewes was maintained in that condition, one group of good- and one of moderate-condition ewes were brought down in condition by restricted feeding and one group of moderate and the very poor condition ewes were raised in condition by a high level of feeding. Ewes were therefore in good, moderately good or poor condition at mating. After mating, ewes were killed either on return to service or at 25 ± 5 days for counts of corpora lutea and viable embryos.Poor body condition, irrespective of feeding level, was associated with a delay or suppression of oestrus and with a high return-to-service rate. Ovulation rate was positively related to body condition at mating but not to the level of pre-mating food intake at the condition levels studied.Embryo mortality decreased as body condition at mating increased and the interaction between condition and the level of pre-mating food intake had a differential effect on mortality of single- and multiple-shed ova. The lowest rate of embryo mortality was found in ewes in moderately good condition which had been well-fed before mating.

Fertility in Cheviot ewes. 2. The effect of level of pre-mating nutrition on ovulation rate and early embryo mortality in North and South Country Cheviot ewes in moderately-good condition at mating

1979 ◽  
Vol 29 (1) ◽  
pp. 17-23 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney ◽  
W. F. Smith
Keyword(s):  
Food Intake ◽  
Good Condition ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Restricted Feeding ◽  
Embryo Mortality ◽  
The North ◽  
Breed Difference ◽  
High Level

ABSTRACTIn two experiments over 2 years, 57 North Country Cheviot and 82 South Country Cheviot hill ewes were differentially group-fed indoors over a 2-month period to achieve either good or moderate body con- dition. Over 5 weeks prior to mating, ewes in good condition were brought down in condition by restricted feeding and ewes in mod- erate condition were raised in condition by a high level of feeding. The ewes were thus in moderately-good condition at mating. After mating, ewes were maintained in this condition until killed either on return to service or at 29 ± 8 days for counts of corpora lutea and viable embryos.Ovulation rate in each breed was positively related to the level of pre-mating food intake at the condition level studied. Embryo mortality, as ova loss, was not influenced overall by the level of pre-mating food intake but loss of multiple-shed ova was greater than that of single-shed ova in ewes which had been on restricted feeding before mating. Although a greater proportion of ewes in the North Country Cheviot breed were not pregnant at slaughter, this could not be identified as a breed difference since the breeds were studied in different years.

The effect of level of pre-mating nutrition on ovulation rate in Scottish Blackface ewes in different body conditions at mating

1984 ◽  
Vol 39 (2) ◽  
pp. 235-239 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney ◽  
W. F. Smith
Keyword(s):  
Food Intake ◽  
Body Condition ◽  
Good Condition ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Restricted Feeding ◽  
Good Level ◽  
Good Score ◽  
Moderate Condition ◽  
High Level

ABSTRACTIn two experiments over 2 years, 181 Scottish Blackface ewes were differentially group-fed indoors to achieve moderately-good (score 2·5), moderate (score 2) or poor (score 1·5) body condition. Over 5 weeks prior to mating, ewes in moderately-good condition were either maintained or brought down to moderate condition by restricted feeding and ewes in moderate and poor condition were raised, respectively, to moderately-good and moderate condition by a high level of feeding. After mating, ewes were maintained in condition until slaughtered for a count of corpora lutea relating to first service. Ovulation rate was positively and significantly related to the level of pre-mating food intake at the moderate level of condition but not significantly so at the moderately-good level. It is postulated that ewes of this breed are more sensitive to the level of pre-mating food intake when in moderate condition at mating than they are when condition has risen to a moderately-good level.

Fertility in Cheviot ewes. 1. The effect of body condition at mating on ovulation rate and early embryo mortality in North and South Country Cheviot ewes

1979 ◽  
Vol 29 (1) ◽  
pp. 11-16 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney
Keyword(s):  
Body Condition ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Embryo Mortality ◽  
Breed Type ◽  
The North ◽  
Breed Difference ◽  
North And South ◽  
Lambing Rate

ABSTRACTIn two experiments over 2 years, 113 North Country Cheviot and 132 South Country Cheviot hill ewes were differentially group-fed over a 10-week period to achieve either good or moderate body con- dition. Ewes were maintained in these levels of condition over the 5 weeks prior to mating. After mating, ewes were killed either on return to service or between days 23 and 85 for counts of corpora lutea and viable embryos.Ovulation rate in each breed was positively related to body condition at mating. Embryo mortality, as ova loss, was not influenced overall by breed, type of ovulation, year of recording, or body condition. Although comparisons of loss were partly confounded by a differen- tial distribution in the number of ova shed in each breed and body condition group, there was an apparent breed difference in loss of single- and multiple-shed ova. Potential lambing rate therefore showed greater response to improved body condition at mating in the North Country Cheviot breed than it did in the South Country Cheviot.

The effect of time of mating on ovulation rate and potential lambing rate of Greyface ewes

1979 ◽  
Vol 29 (2) ◽  
pp. 277-282 ◽  
Author(s):  
R. G. Gunn ◽  
J. M. Doney ◽  
W. F. Smith
Keyword(s):  
Body Condition ◽  
Body Condition Score ◽  
Ovulation Rate ◽  
Stress Factors ◽  
Corpora Lutea ◽  
Differential Group ◽  
Condition Score ◽  
Group Feeding ◽  
Lambing Rate

ABSTRACTOver 2 years, 104 Greyface ewes were mated at a synchronized oestrus either in early October or early November. From late September until slaughter at return to service or between 4 and 7 weeks after mating, ewes were fed to maintain their body condition score as previously adjusted by differential group feeding on grass. Ovulation rate and potential lambing rate were derived from counts of corpora lutea and viable embryos at slaughter. Both rates were higher in the early-mated ewes in comparable body condition. Stress factors were implicated as contributing to the decline in ovulation rate with time, while ewes which failed to hold to first mating were largely responsible for the decline in potential lambing rate.

scholarly journals Effects of Incubation Conditions and Offspring Sex on Embryonic Development and Survival in the Zebra Finch (Taeniopygia Guttata)

The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1239-1248 ◽  
Author(s):  
Helen E. Gorman ◽  
Kate J. Orr ◽  
Aileen Adam ◽  
Ruedi G. Nager
Keyword(s):  
Embryonic Development ◽  
Body Condition ◽  
Egg Quality ◽  
Good Condition ◽  
Taeniopygia Guttata ◽  
Egg Laying ◽  
Male And Female ◽  
Embryo Mortality ◽  
Offspring Fitness ◽  
Offspring Sex

AbstractSuboptimal conditions during embryonic development can affect offspring fitness. Both egg quality and incubation behavior can affect hatching success, hatching mass, and subsequent offspring performance. These effects may differ between male and female offspring. We manipulated the prebreeding body condition of Zebra Finches (Taeniopygia guttata), using diets of different protein content. To separate possible effects on egg quality of parental body condition and incubation conditions, we did a cross-fostering experiment. We analyzed embryo survival and hatching mass with respect to body condition of the egg-laying parent, body condition of the incubating foster parent, and offspring sex. Embryos were not affected by the condition of the egg-laying parent. Eggs incubated by parents in better condition suffered less embryo mortality than those incubated by parents in poorer condition, but only when overall embryo mortality was low. Hatching mass was also affected by the incubating foster parent’s body condition. And hatchlings incubated by parents in good condition were heavier than those incubated by parents in poor condition. Female hatchlings from late-laid eggs were heavier, in comparison with the size of the egg from which they hatched, than female hatchlings from earlier-laid eggs. No such effect was found for males. Therefore, male and female embryos may differ in their sensitivity to suboptimal conditions during embryonic development. These results suggest that parental body condition during incubation can affect offspring fitness.Efectos de las Condiciones de Incubación y el Sexo de las Crías sobre el Desarrollo Embrional y la Supervivencia en Taeniopygia guttata

scholarly journals 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 ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 3674-3684 ◽  
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.

The effect of body condition on ovulation rate in the sow

1969 ◽  
Vol 11 (4) ◽  
pp. 505-510 ◽  
Author(s):  
B. Hardy ◽  
G. A. Lodge
Keyword(s):  
Weight Loss ◽  
Body Weight ◽  
Body Condition ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Pooled Data ◽  
Conception Rates

SUMMARYTwenty-four sows from three nutritional regimes imposed until weaning of their third litters were used to investigate the influence of weight and body condition on ovulation rate.For low-, medium- and high-plane sows respectively, mean corpora lutea numbers at 3 to 6 days post coitus were 13·8±0·78, 16·4±0·87 and 15·2±1·01 (not significantly different); conception rates at first service were 50, 87·5 and 100% percentages prenatal mortality were 36·1±7·95, 67·2±7·26 and 41·7±7·26, and mean numbers of pigs born alive were 9·0±1·19, 5·2±1·09 and 8·8±1·09.Pooled data indicated no significant effect of body weight but a significant effect of weight loss during the preceding lactation on ovulation rate (P<0–01).

scholarly journals Effects of flush feeding strategy before breeding on reproductive performance of modern replacement gilts: impacts on ovulation rate and litter traits

2020 ◽  
Vol 98 (6) ◽  
Author(s):  
André L Mallmann ◽  
Lidia S Arend ◽  
Gabriela S Oliveira ◽  
Ana P G Mellagi ◽  
Rafael R Ulguim ◽  
...  
Keyword(s):  
Litter Size ◽  
Reproductive Performance ◽  
Feeding Strategy ◽  
Early Embryo ◽  
Ovulation Rate ◽  
Breeding Cycle ◽  
Corpora Lutea ◽  
Embryo Survival ◽  
Estrous Cycles ◽  
Litter Traits

Abstract AbstractThe effects of two feed levels offered during two estrous cycles before insemination were evaluated on the reproductive performance of gilts. A total of 93 gilts (PIC Hendersonville, TN) were individually housed and manually fed twice a day with 2.1 or 3.6 kg/d of a corn and soybean meal-based diet (3.15 Mcal ME/kg and 0.64% standardized ileal digestible lysine), during two estrous cycles before breeding (cycle 1, between first and second estrus; cycle 2, between second and third estrus). Gilts were weighed at the beginning of the experiment, at second and third estrus, and at slaughter (30.2 ± 1.2 d of gestation). Follicles were counted at second estrus, and the embryo-placental units and the corpora lutea were individually counted, measured, and weighed at slaughter. Gilts fed 3.6 kg/d had greater BW gain during cycle 1 and cycle 2 (P &lt; 0.001; + 9.8 kg and + 10.0 kg, respectively) becoming heavier at second and third estrus (P &lt; 0.001). At second estrus, gilts fed 3.6 kg/d had 1.6 more medium-large follicles (P = 0.074) but no difference in follicle size (P = 0.530) was observed. Gilts fed 3.6 kg/d in cycle 1 or cycle 2 had a greater ovulation rate at third estrus (P &lt; 0.016) than those receiving 2.1 kg/d. Also, 3.6 kg/d in cycle 2 increased early embryo mortality (P = 0.006; 2.3 vs. 1.1 dead embryos) and consequently reduced total embryo survival (P = 0.002; 84.6 vs. 90.1%). Gilts fed 3.6 kg/d during cycle 1 had two more total embryos (P &lt; 0.001; 17.2 vs. 15.1) and two more vital embryos on day 30 (P &lt; 0.001; 16.7 vs. 14.5) in comparison with gilts fed 2.1 kg/d. The coefficient of variation for placental length was greater for gilts fed 3.6 kg/d during cycle 1 (P = 0.003). No further significant effects of feeding levels were observed on embryo and placental traits (P ≥ 0.063). These results suggest that the feeding level during the first cycle after pubertal estrus is crucial to set ovulation rate and potential litter size for breeding at next estrus. However, flush feeding gilts before insemination can negatively impact litter size by reducing embryo survival when breeding at third estrus.

Pre-mating herbage intake and the reproductive performance of north Country Cheviot ewes in different levels of body condition

1991 ◽  
Vol 52 (1) ◽  
pp. 149-156 ◽  
Author(s):  
R. G. Gunn ◽  
W. F. Smith ◽  
A. J. Senior ◽  
E. Barthram ◽  
D. A. Sim ◽  
...  
Keyword(s):  
Body Condition ◽  
Reproductive Performance ◽  
The Body ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Mating Period ◽  
The North ◽  
Herbage Intake ◽  
Low Sensitivity ◽  
Body Condition Scores

ABSTRACTOver 4 years, a flock of mature North Country Cheviot ewes was grazed on different swards between weaning in August and mid October to achieve a range of condition scores at 5 weeks before mating (post-weaning period). During the subsequent 5 weeks before a synchronized mating (pre-mating period), all ewes were grazed on a perennial ryegrass/white clover sward, provided at high (H) or low (L) herbage masses (1600 to 2100 or 1200 to 1400 kg dry matter (DM) per ha, respectively). Ovulation rate was derived from the number of corpora lutea in 101 ewes slaughtered after first mating. Conception and lambing rates were derived from the number of lambs born to first mating of 406 ewes. In 2 out of the 4 years, 79 ewes were used to estimate herbage intake.There was no effect of post-weaning management on reproductive performance. Herbage intake and reproductive performance were examined in relation to the body condition of the ewes at 5 weeks before mating. On an H herbage mass pre-mating, herbage intake in the period immediately prior to mating was greatest in ewes in low body condition and declined significantly with increasing condition. On an L herbage mass pre-mating, herbage intake did not vary significantly with condition. Ovulation rate was low in ewes in low body condition (scores =≤·25) at 5 weeks before mating, increased significantly with increasing condition up to scores 2·50/2·75 but did not change significantly above such intermediate scores. Conception and lambing rates increased significantly with increasing body condition up to scores 2·50/2·75 and then decreased significantly as condition increased above these levels. These effects of body condition were greater on an L herbage mass pre-mating than they were on an H herbage mass. Ewes in the intermediate body condition scores of 2·50 and 2·75 at 5 weeks before mating had a low sensitivity to contemporary nutrition pre-mating. Such condition levels are therefore considered to be above the range of condition in the North Country Cheviot breed within which reproductive response is affected by contemporary nutrition pre-mating.The lower reproductive performance of ewes in high body condition (scores 3=3·00) at 5 weeks before mating was related to an increase in estimated ova and embryo loss and may be associated with a reduced herbage intake.

Sign in / Sign up

Export Citation Format

Share Document