EFFECT OF FEEDING ETHINYLOESTRADIOL FOR VARIOUS PERIODS BEFORE MATING ON REPRODUCTION IN THE HAMSTER

1972 ◽  
Vol 70 (3) ◽  
pp. 582-590
Author(s):  
B. K. Davis ◽  
I. Noske ◽  
M. C. Chang

ABSTRACT Ethinyloestradiol (EO) fed for various periods before mating to female hamsters affected the timing of mating and pregnancy rate. Slight effects on ovulation, foetal-crown rump length and resorption may have occurred, but effects on implantation were not apparent among pregnant hamsters. The response observed depended upon the feeding schedule adopted: hamsters fed 2.5 mg EO in a single dose, on day 3 before mating, mated normally but had a significantly lower pregnancy rate; on the other hand, animals fed 2.5 mg EO (0.21 mg/day) over three oestrous cycles, days 14–3 before mating, showed variations in the time of mating but had an essentially normal pregnancy rate; and, a group of hamsters who received the same total amount of EO (0.63 mg/day) over one oestrous cycle, days 6–3 premating, showed untowards effects by the steroid on both the timing of mating and pregnancy rate. The implications of these results are considered in relation to fertility control.

1966 ◽  
Vol 53 (2) ◽  
pp. 212-224 ◽  
Author(s):  
Carla Rossi Cartoni ◽  
G. Bignami

ABSTRACT The formation of deciduomata was investigated in ovariectomized rats treated with various combinations of oestrogen and progesterone before traumatization. The hormonal treatment was kept constant for all groups of animals during the period between traumatization and autopsy (4 mg of progesterone and 0.2 μg of oestradiol benzoate daily). Uterine weight and carbonic anhydrase activity were measured 96 hours after trauma and compared with those of intact controls receiving traumatization on day 4 of pseudopregnancy. When a single dose of oestrogen was given on the day before traumatization, induction of decidualization was successful under a wide variety of experimental conditions (presence or absence of oestrogen »priming« before the beginning of the progesterone treatment; progesterone treatment of varying duration). On the contrary, treatment with divided doses of oestrogen, given for 3 days before trauma, allowed extensive decidualization only in rats »primed« with oestrogen, and traumatized on the fourth day of a progesterone treatment started 24 hours after vaginal keratinization. It appears therefore that only the »oestrogen surge« hypothesis of Shelesnyak and his collaborators can account for those conditions in which implantation occurs at variable intervals of time after the last oestrus (lactation, hypophyseal autotransplantation, administration of a tranquilizer and early ovariectomy followed by hormonal treatment). On the other hand, both the hypothesis of Shelesnyak and that proposed by Yochim & DeFeo (1963) (i. e. continuous secretion of small amounts of oestrogen during the first three days of pregnancy and pseudopregnancy) could account for the rapid waxing and waning of endometrial sensitivity to deciduoma-inducing stimuli observed in normal pregnancy and pseudo-pregnancy.


Author(s):  
Marianela Lorier ◽  
Pietro Fagiolino ◽  
Marta Vázquez ◽  
Manuel Ibarra ◽  
Natalia Guevara

Background: The aim was to determine the effect of feeding on chiral inversion of Ibuprofen isomers. Method: Six healthy volunteers participated in a two-treatment crossover study where a single dose of Ibuprofen racemate was given. One stage consisted in an 8-hour interval of fasting, while in the other, the drug was administered with a solution of saccharose and a standard food intake regimen was implemented.


Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 538
Author(s):  
Vita Maria Marino ◽  
Teresa Rapisarda ◽  
Margherita Caccamo ◽  
Bernardo Valenti ◽  
Alessandro Priolo ◽  
...  

Hazelnut peel (HNP), a by-product from the chocolate industry, is considered to be a suitable ingredient to be included in the diet of ruminants. This study aimed to evaluate the effect of feeding dairy ewes with a diet containing HNP on ripened cheese quality, including fatty acid (FA) profile, cholesterol, and tocopherol content, as well as stability during storage under commercial conditions. In total, 10 experimental cheeses were produced with bulk milk obtained from ewes fed a commercial concentrate (C group; n = 5) or a concentrate containing 36% HNP in dry matter (HNP group; n = 5). After 40 days of aging, each cheese was sub-sampled into three slices: one was analyzed immediately (C0 and HNP0), and the other two were refrigerated and analyzed after seven days (C7 and HNP7) and 14 days (C14 and HNP14), respectively. Compared to C, HNP cheese had more than twice as many tocopherols and mono-unsaturated FA and respectively 38% and 24% less of cholesterol and saturated FA. Tocopherols and cholesterol levels remained rather stable up to 14 days of storage regardless of the experimental group, suggesting no cholesterol oxidation. Therefore, the inclusion of HNP in ewe diets could be a valid resource to produce cheese with a healthier lipid profile and higher tocopherols content.


2004 ◽  
Vol 16 (2) ◽  
pp. 197 ◽  
Author(s):  
A. Fischer-Brown ◽  
R. Monson ◽  
D. Northey ◽  
T. Kuhlka ◽  
J. Rutledge

Developmental aberrations following transfer of in vitro-produced bovine embryos can result in early gestational losses and offspring abnormalities. An ongoing study tests the hypothesis that such aberrations occur with equal frequency among commonly employed culture systems. In year 1, embryos were produced using oocytes from abattoir-derived ovaries (breed unspecified) and a proven Angus bull selected for low birth weight. IVC treatments were 2×2 factorial for medium (KSOMaa or SOFaa) and oxygen concentration (5% or 20%). Angus recipients (n=61; 32 cows, 29 heifers) were randomly allotted to treatments for Day 7 transfers. Pregnancy was diagnosed with ultrasound several times during gestation (Table 1). At parturition calf weight, shoulder height, chest circumference, crown-rump length, and humeral and femoral length data were collected. Statistical analyses (Statistical Analysis System, Cary, NC) were logistic regression with a binomial distribution for pregnancy rate, and the general linear models procedure for calf measurements; included were fixed effects of medium, oxygen, and their interaction, with additional fixed effects of dam parity and calf sex where appropriate. No significant effects of medium or oxygen were found for pregnancy rate or calf measurements other than birth weight. Mean birth weight was higher in the KSOM, 20% oxygen treatment (Table 1), and medium-oxygen interaction for calf weight was also significant (P<0.01). In year 2 embryos were produced using the same Angus bull and Angus oocytes. Angus recipients (n=38; 32 cows, 6 heifers) were randomly allotted to treatments. Fetal crown-rump lengths were measured by ultrasound weekly from Days 33 to 54 and were analyzed as repeated measures using the mixed procedure. Pregnancy outcome and LS means for crown-rump lengths are included in Table 1. Though insufficient recipient numbers preclude determination of statistical significance, of interest is the relatively small fetal size in early gestation and large birth weights in the KSOM, 20% oxygen treatment. This treatment also contained a Day 33 pregnancy, subsequently lost by Day 40, in which the fetus was too small to obtain an accurate measurement. Fetal growth will continue to be monitored throughout gestation. Data will be collected at parturition as in year 1, and pooled analyses will be done. Table 1


1972 ◽  
Vol 53 (1) ◽  
pp. 31-35 ◽  
Author(s):  
K. BROWN-GRANT ◽  
C. S. CORKER ◽  
F. NAFTOLIN

SUMMARY Plasma luteinizing hormone (LH) concentrations were already lower on Day 2 of pregnancy than at the same time after the preceding ovulation in the non-pregnant rat, and fell progressively up to Day 16 of pregnancy. No evidence was obtained of any increase at the time when the ovulatory surge of LH would have occurred if the animal had not become pregnant. Pituitary LH concentration was lower in mated rats on the morning of Day 0 of pregnancy than in unmated controls on the morning of the day of oestrus. Subsequently it increased slowly to reach a level higher than at any stage of the oestrous cycle by Day 8 of pregnancy and remained high until at least Day 16 of pregnancy. Peripheral plasma oestradiol concentration increased late on Day 2 of pregnancy and was still raised on Day 4 but was never more than about one fourth of the peak concentration seen on the morning of prooestrus during the oestrous cycle. There were similar changes in plasma LH and oestradiol concentrations in the 48 h after a single injection of 2·5mg progesterone on the morning of the day of dioestrus, a procedure that delays ovulation by 1 or 2 days. Administration of a synthetic progestational compound (medroxyprogesterone acetate) to pregnant rats delayed blastocyst implantation and the delay was associated with a marked decrease in peripheral plasma LH to levels below those of normal pregnancy.


1996 ◽  
Vol 1996 ◽  
pp. 78-78
Author(s):  
N.B. Prescott ◽  
T.T.F. Mottram ◽  
A.J.F. Webster

An automatic milking system (AMS) has the potential to milk cows when the cow chooses. However cows must attend the system at an appropriate frequency. The provision of food in the AMS is a robust, way of luring cows into the system. The system can be arranged such that the cows have to visit the AMS to access food in the exit area the other side. Here they can be fed forage or concentrate. It has been shown that feeding cows forage as a lure can result in modified forage feeding behaviour, and this may be to the detriment of the cows (Winter, 1993, Ketelaar-de-Lauwere, 1992). Feeding concentrate in the exit area may be an alternative design if the level of attendance generated is high enough. Cows can also be fed concentrate in the milking stall of the AMS. The aim of this experiment was to compare die effects of feeding forage or concentrate in the exit area and the effect of feeding or not feeding concentrate in the milking stall on attendances, and lying and feeding behaviour.


1990 ◽  
Vol 36 (12) ◽  
pp. 2097-2101 ◽  
Author(s):  
K Emancipator ◽  
J L Bock ◽  
M D Burke

Abstract We compare three methods for using the rate of change of human choriogonadotropin (hCG) concentration in serum to diagnose ectopic pregnancy. With Method I, the lower limit for the rate of increase of serum hCG in normal pregnancy is 66% per 48 h. With Method II, a different lower limit of normal is specified for each of four discrete sampling intervals of hCG. With Method III, the lower limit of normal is determined by a continuous discriminant function of the initial hCG concentration. If the initial hCG concentration is less than or equal to 2000 int. units/L (Second International Standard), all three methods have acceptable diagnostic efficiencies, and there are no statistically significant differences among conclusions from the methods. None of the three methods performs satisfactorily if the initial hCG concentration is greater than 2000 int. units/L. We recommend Method I because it is simpler than the other two.


1997 ◽  
Vol 43 (12) ◽  
pp. 2233-2243 ◽  
Author(s):  
Laurence A Cole

Abstract Multiple hCG-related molecules are present in pregnancy serum and urine samples. These include nonnicked hCG (the hormone), nicked hCG, hyper- and hypoglycosylated hCG, hCG missing the C-terminal extension, free α-subunit, large free α-subunit, free β-subunit, nicked free β-subunit, and β-core fragment. Over 100 immunoassays are sold for quantifying hCG-related molecules in serum or urine. Each measures nonnicked hCG and one of seven combinations of the other hCG-related molecules. This is the source of interassay discordance in hCG determinations. Whereas minor variations are noted in different kit results in normal pregnancy samples (more than twofold variation), much larger variations may be found in two immunoassay results in irregular gestations (spontaneous abortion, aneuploidy, preeclampsia, cancers, and trophoblast disease). Care is needed in choosing an immunoassay. What the assay measures may be more important than its cost or speed. This article reviews the structure of hCG and related molecules. It examines the stability and degradation of hCG, and recognition of hCG-related molecules by different types of immunoassay. Also reviewed are new assays for specifically detecting these other hCG-related molecules.


2019 ◽  
Vol 31 (12) ◽  
pp. 1904 ◽  
Author(s):  
Juan Cuervo-Arango ◽  
Anthony N. Claes ◽  
Tom A. E. Stout

In recent years, the number of equine invitro-produced embryos (IVP) has increased markedly; as yet, there are few reports on what constitutes an ‘ideal’ recipient for an IVP embryo. This study retrospectively investigated the effects of recipient mare oestrous cycle characteristics on the likelihood of pregnancy after transfer of IVP (n=264) and invivo-derived embryos (n=262). IVP embryos tolerated only a narrow window of recipient mare ‘synchrony’, with transfer on Day 4 after ovulation resulting in a higher likelihood of ongoing pregnancy (69%) than transfer on Days 3, 5 or 6 (53.2%, 41.3% and 23.1% respectively; P=0.02). In contrast, Day 8 invivo-derived embryos tolerated a wide range of uterine (a)synchrony, with no difference in pregnancy or pregnancy loss for recipients that ovulated between Day 4 and Day 9 before transfer. However, transferring invivo-derived embryos to recipients that had a longer oestrus preceding transfer resulted in higher Day 12 and ongoing pregnancy rate (P<0.01). This effect was not significant in IVP embryos. In conclusion, Day 6–8 IVP blastocysts survive best after transfer to Day 4 recipient mares; Day 8 invivo-derived embryos survive equally well in Day 4–9 recipients, but do better in mares that have a long preceding oestrus.


1987 ◽  
Vol 65 (2) ◽  
pp. 130-135 ◽  
Author(s):  
S. G. A. Power ◽  
J. R. G. Challis

Changes in estrogen production are considered important in the sequence of events leading to parturition. We sought tissue-specific changes in the concentration of unconjugated estrone (E1) and estradiol (E2) in intrauterine fetal (amnion, chorion) and maternal (endometrium, myometrium) tissues during normal pregnancy, labour, and ACTH-induced labour in sheep. The mean concentrations of E1 and E2 in the fetal membranes were higher than in endometrium and myometrium. In amnion there were no consistent changes in estrone concentrations with gestation, although estradiol concentrations increased between day 130 and term. In the endometrium there were increases in both estrone and estradiol between day 100 and term, whereas in the myometrium increases in the concentrations of E1 and E2 occurred between days 130–135 and term. Animals showing a labourlike pattern of uterine contractions after intrafetal ACTH administration did not show significant differences in estrone or estradiol concentrations in amnion, chorion, or endometrium compared with saline-infused controls. However, there was a progressive increase in the concentration of estrone and estradiol in the myometrium during ACTH-induced labour. We conclude that changes in the concentrations of estrone and estradiol in intrauterine tissues vary between the tissues studied and the two estrogens. In general, estrogen concentrations increased towards term, but this trend was more marked in the maternal than fetal tissues. The changes in estrone concentrations in myometrium, but not in the other tissues, were replicated during ACTH-induced labour. Our results would be compatible with the suggestion that tissue-specific changes in estrogen concentrations may contribute to the local intrauterine steroid milieu during pregnancy and at term.


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