scholarly journals Effect of the Interaction of Body Weight and Daily Estradiol Benzoate Injections on the Onset of Estrous Cyclicity in Rats

1980 ◽  
Vol 23 (4) ◽  
pp. 733-736 ◽  
Author(s):  
R. Thomas Gentry ◽  
George N. Wade
Keyword(s):  
Body Weight ◽  
Estradiol Benzoate ◽  
Estrous Cyclicity

THE INFLUENCE OF GILT AGE ON THE ENDOCRINE AND OVULATORY RESPONSE TO DIFFERENT DOSES OF ESTRADIOL BENZOATE

1988 ◽  
Vol 68 (3) ◽  
pp. 979-982 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
F. X. AHERNE
Keyword(s):  
Body Weight ◽  
Luteinizing Hormone ◽  
Key Words ◽  
Jugular Vein ◽  
Estradiol Benzoate ◽  
Blood Samples ◽  
Estrous Cyclicity ◽  
The Mean ◽  
Different Doses ◽  
Phasic Release

Fifty-five prepubertal Yorkshire × Landrace gilts were randomly assigned to one of six treatments involving the injection (i.m.) of estradiol benzoate (EB) at either 10 or 20 μg kg−1 body weight at gilt ages of 130, 150 or 170 d. Blood samples were taken by jugular vein puncture at 0, 24, and 36 h, and then at 6-h intervals until 84 h, after injection and assayed for plasma luteinizing hormone (LH) concentrations. The mean magnitude of the EB-induced LH peak was 6.1 ± 0.2 ng mL−1, and was not affected by treatment. Fifty-six percent of gilts ovulated in response to EB injection, and 34% had a subsequent ovulation. The initial ovulation rate was unaffected by EB dose, but was higher (P < 0.05) in 170 d (9.9 ± 1.0) compared to younger gilts (4.2 ± 1.1 and 5.5 ± 1.1 for 130-dand 150-d gilts, respectively). Subsequent ovulation rates were unaffected by treatment. It is concluded that EB treatment will usually induce a phasic release of LH from prepubertal gilts, but this release is not necessarily accompanied by normal estrous cyclicity. Key words: Estradiol, gilts, ovulation

PSX-B-5 Effect of replacement of dry-rolled corn with un-processed rye on growth performance, efficiency of dietary net energy utilization, and carcass traits of finishing heifers

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 458-459
Author(s):  
Keith M Buckhaus ◽  
Warren C Rusche ◽  
Zachary K Smith
Keyword(s):  
Body Weight ◽  
Growth Performance ◽  
Block Design ◽  
Average Daily Gain ◽  
Estradiol Benzoate ◽  
Energy Utilization ◽  
Net Energy ◽  
Final Body Weight ◽  
Trenbolone Acetate ◽  
Finishing Diets

Abstract Continental × British beef heifers were used in a randomized complete block design experiment to evaluate the effects of replacing dry-rolled corn with unprocessed rye on growth performance, efficiency of dietary net energy (NE) utilization, and carcass trait responses in finishing heifers. Heifers (n = 56; 433 ± 34.0 kg) were transported 241 km from a regional sale barn to the Ruminant Nutrition Center in Brookings, SD. Heifers were blocked by weight grouping and then allotted to pens (n = 7 heifers/pen and 4 pens/treatment). Treatments included a finishing diet that contained 60% grain (DM basis) as dry-rolled corn (DRC) or unprocessed rye grain (RYE). On d 14, heifers were consuming the final diet and were implanted with 200 mg of trenbolone acetate and 28 mg of estradiol benzoate (Synovex-Plus, Zoetis, Parsippany, NJ). RYE heifers had decreased (P ≤ 0.01) final body weight, average daily gain, and gain efficiency; but tended (P = 0.08) to have a greater dry matter intake compared to DRC. RYE had decreased (P ≤ 0.01) observed dietary NE and decreased (P ≤ 0.01) observed-to-expected dietary NE ratio for maintenance and gain compared to DRC. Dressing percentage, 12th rib fat thickness, ribeye area, and the distribution of USDA yield and quality grades were not altered (P ≥ 0.12) by diet. Hot carcass weight, yield grade, estimated empty body fat (EBF), and body weight at 28% EBF decreased (P ≤ 0.02) and retail yield increased (P= 0.01) in RYE compared to DRC. These data indicate that unprocessed rye is a palatable feed ingredient for inclusion in finishing diets for beef cattle and that rye inclusion only minimally influences carcass quality. The feeding value of unprocessed rye is considerably less (21.4%) than that of dry-rolled corn using current standards and approximately 91% of the NE value of processed rye.

scholarly journals Perinatal exposure to low doses of bisphenol A affects body weight, patterns of estrous cyclicity, and plasma LH levels.

2001 ◽  
Vol 109 (7) ◽  
pp. 675-680 ◽  
Author(s):  
B S Rubin ◽  
M K Murray ◽  
D A Damassa ◽  
J C King ◽  
A M Soto
Keyword(s):  
Body Weight ◽  
Bisphenol A ◽  
Perinatal Exposure ◽  
Low Doses ◽  
Estrous Cyclicity

Food intake, body weight, and adiposity in female rats: actions and interactions of progestins and antiestrogens

1981 ◽  
Vol 240 (5) ◽  
pp. E474-E481 ◽  
Author(s):  
J. M. Gray ◽  
G. N. Wade
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Food Intake ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
Antiestrogenic Activity ◽  
Ovx Rats ◽  
Increase Food Intake ◽  
Series Of Experiments ◽  
Adipose Tissue Lipoprotein Lipase

A series of experiments examined the effects of two progestins, progesterone and R 5020, and two nonsteroidal antiestrogens, nafoxidine and MER-25, on body weight and composition in female rats. Both progesterone and R 5020 increased food intake, body weight, and carcass adiposity in ovariectomized (OVX) rats treated with estradiol benzoate (EB), but neither progestin had any effect on these measures in OVX rats not treated with EB. R 5020 was substantially more effective than progesterone on all end points. Nafoxidine and MER-25 mimicked the actions of estradiol and decreased adipose tissue lipoprotein lipase (LPL) activity by 75–80%. For adipose tissue LPL activity, both nafoxidine and MER-25 were full estrogen agonists and without antiestrogenic activity. Nafoxidine also mimicked the effects of EB by reducing food intake, body weight, and carcass adiposity in OVX rats. In contrast, nafoxidine antagonized the induction of cytoplasmic progestin ([3H]R 5020) binding sites by EB in parametrial adipose tissue of OVX rats. In nafoxidine-treated OVX rats, concurrent progesterone administration had no effect on adipose tissue LPL activity, but progesterone did increase food intake, body weight, and carcass fat content. Some physiological mechanisms by which gonadal steroids may act to influence eating and adiposity are discussed.

The effect of a single injection of estradiol benzoate on thyroid function in intact male rats

1968 ◽  
Vol 46 (4) ◽  
pp. 697-700 ◽  
Author(s):  
K. Brown-Grant
Keyword(s):  
Body Weight ◽  
Thyroid Gland ◽  
Thyroid Function ◽  
Dose Level ◽  
Adult Male ◽  
Single Injection ◽  
Estradiol Benzoate ◽  
Male Rats ◽  
Intact Male ◽  
Federation Proc

The changes observed in the metabolism of radioiodide and radiophosphorus by the thyroid gland of intact adult male rats following a single injection of estradiol benzoate (4 μg/100 g body weight) are consistent with the suggestion (F. Labrie, G. Pelletier, and C. Fortier. Federation Proc. 26, 484 (1967). Abstr.) that at this dose level estrogen causes a hypersecretion of TSH in such animals.

scholarly journals SUN-239 Effects of High-Fat Diet-Induced Obesity on Pulsatile LH Secretion and Hypothalamic KISS1 Expression in Female Rats

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Shiori Minabe ◽  
Kinuyo Iwata ◽  
Youki Watanabe ◽  
Hitoshi Ozawa
Keyword(s):  
Body Weight ◽  
High Fat Diet ◽  
Pulse Frequency ◽  
Female Rats ◽  
Standard Diet ◽  
High Fat ◽  
Estrous Cycles ◽  
Menstrual Dysfunction ◽  
Estrous Cyclicity ◽  
Lh Secretion

Abstract Female obesity is associated with menstrual dysfunction leading to anovulation and infertility. It has recently been reported obesity-induced infertility is involved in the dysfunction of a kisspeptin neuron, a key player in reproduction via direct stimulation of gonadotropin releasing hormone (GnRH) and subsequent gonadotropin release in mammalian species. Previous studies reported that obesity due to high-fat diet (HFD) for 8 months induced a disruption in estrous cyclicity, caused by a decrease in Kiss1 (coding kisspeptin) expression in the hypothalamic arcuate nucleus (ARC) in female rodents. Here we showed the effects of shorter-term (4 months) HFD on pulsatile LH secretion and hypothalamic Kiss1 expression to show pathogenic mechanism underlying obesity-induced infertility. Female Wistar-Imamichi strain rats (7 weeks old) fed on either a standard diet (10% calories from fat) or a high-fat diet (45% calories from fat) for 4 months. Estrous cyclicity and body weight were monitored regularly. All animals were implanted with a jugular catheter and collected blood samples to analyze pulsatile LH secretion, after a week of the ovariectomy with low-dose replacement estradiol to negate influence of changes in ovarian steroid levels and mimic diestrous levels of plasma estrogen. On the next day of the blood sampling, rats were perfused with 0.05 M PBS followed by 4% paraformaldehyde and their brains were collected for in situ hybridization of Kiss1 and Gnrh1. The HFD-fed rats showed progressive increases in body weight, along with hyperphagia and adipose tissue accumulation, compared with control animals. Fifty-eight percent of the HFD-fed rats exhibited irregular estrous cycles, whereas remaining HFD-fed rats showed regular cycles. Two out of 7 rats showing HFD-induced irregular estrous cycles exhibited profound suppression of the LH pulse frequency and the number of Kiss1-expressing cells in the ARC, whereas remaining HFD-fed rats showed normal LH pulses and ARC Kiss1 expressions. The number of Kiss1-expressing cells in the ARC had close positive correlation with LH pulse frequency (R2=0.6872, P&lt;0.001) in both groups. Additionally, the number of Kiss1- or Gnrh1-expressing cells in the anteroventral periventricular nucleus or the preoptic area, were comparable between groups. Taken together, our finding reveals the possibility that irregular menstruation was also induced by changes in the kisspeptin-GnRH independent pathway during the incipient stage of obese infertility.

scholarly journals Effects of estradiol and progesterone on food intake, body weight, and carcass adiposity in weanling rats

1981 ◽  
Vol 240 (5) ◽  
pp. E499-E503 ◽  
Author(s):  
S. M. Schwartz ◽  
G. N. Wade
Keyword(s):  
Body Weight ◽  
Adipose Tissue ◽  
Weight Gain ◽  
Food Intake ◽  
Body Weight Gain ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
Reduce Food Intake ◽  
Reduced Body ◽  
Adipose Tissue Lipoprotein Lipase

The effects of estradiol and progesterone on food intake, body weight, carcass adiposity, and adipose tissue lipoprotein lipase (LPL) activity were investigated in weanling female rats. Treatment with estradiol benzoate (EB) reduced body weight gain in ovariectomized (OVX) weanlings as it does in adults. However, other responses to EB were attenuated or absent in weanlings. EB treatment did not reduce food intake, carcass adiposity, or adipose tissue LPL activity. This impaired responsiveness to EB may be due to decreased levels of cytoplasmic estrogen receptors in liver and adipose tissue (but not hypothalamus) in weanlings. On the other hand, responsiveness to progesterone was adultlike in weanlings. Treatment of OVX, EB-primed weanlings with progesterone increased food intake, body weight gain, and carcass adiposity. This adultlike responsiveness to progesterone was associated with adultlike levels of adipose tissue progestin receptors. However, progesterone treatment did not increase adipose tissue LPL activity in weanlings, indicating that changes in LPL activity are not necessary for progesterone-induced obesity.

160 PREGNANCY RATES AFTER USING THE CIDR-G DEVICE AND FIXED-TIMED ARTIFICIAL INSEMINATION IN WHITE-TAIL DEER

2008 ◽  
Vol 20 (1) ◽  
pp. 160
Author(s):  
G. T. Gentry Jr ◽  
J. Saenz ◽  
W. Forbes ◽  
K. Whitehead ◽  
D. Sanders ◽  
...  
Keyword(s):  
Body Weight ◽  
Treatment Group ◽  
Artificial Insemination ◽  
Prostaglandin F2α ◽  
Estradiol Benzoate ◽  
Pregnancy Rates ◽  
Gestation Length ◽  
Treatment Groups ◽  
Timed Artificial Insemination ◽  
Synchronization Protocol

Two synchronization protocols for fixed-timed AI (FTAI) in White-tail deer were evaluated over a 2-year period. InYear 1, White-tail does (n = 38), with a mean body weight of 55 kg and mean age of 2.4 years, were stratified by weight, age, and last fawning date randomly across 2 estrous cycle synchronization treatment groups. Does received either a CIDR-G device for 14 days (CIDR 14) and underwent AI 60 h post-CIDR removal, or received a CIDR-G device for 7 days (CIDR 7) with 1 mg of estradiol benzoate (i.m.) at CIDR insertion (Day 0), 25 mg of prostaglandin F2α (PGF2α; Dinoprost) on Day 6 and 1 mg of estradiol benzoate (i.m.) on Day 7 with AI occurring 52 h post-CIDR removal. In Year 2, White-tail does (n = 36), with a mean body weight of 60 kg and mean age of 3.9 years, were stratified as described for Year 1 and allotted to 2 treatments. Does received a CIDR-G device for 14 days and were inseminated 60 h post-CIDR removal (Treatment A) or were synchronized in the same way as does inTreatment A but also received 200 IU (i.m.) of eCG (Sigma, St. Louis, MO) at CIDR removal (Treatment B). All does received 1 mg of Domosedan (i.v.) before initiating the AI procedure. In both years, electroejaculated semen was collected from a single buck and frozen for AI. In both years, clean-up bucks were introduced into the pen with does for natural cover at no less than 14 days following AI. A gestation length of 195 � 7 days was used to determine whether the fawn(s) resulted from AI or from natural mating. In Year 1, FTAI pregnancy rates were not different between the CIDR 14 (56%) and CIDR 7 (24%) treatment groups. Likewise, pregnancy rates were not different between CIDR 14 FTAI (56%) and clean-up bucks (75%). However, the FTAI pregnancy rate was lower (P < 0.001) for the CIDR 7 treatment group (24%) compared with the clean-up bucks (100%). Treatments did not affect fecundity rates; however, those females pregnant from FTAI had lower (P < 0.001) fecundity rates compared with those females pregnant from natural cover (1.2 v. 1.9 fawns/doe). In Year 2, treatment did not affect FTAI pregnancy rates across treatments (33% for Treatment A and 55% Treatment B); however, fewer (P = 0.024) does in Treatment A were pregnant following FTAI (33%) compared with those pregnant from clean-up bucks (75%). There was no difference in FTAI fecundity rates across treatment groups (1.3 v. 1.7 for Treatments A and B, respectively) or between FTAI treatments and natural cover (1.3, 1.7, and 1.5 for Treatments A, B, and clean-up bucks, respectively). These results indicate that the use of a 14-day CIDR synchronization protocol with FTAI occurring 60 h after CIDR removal yields acceptable pregnancy rates of White-tail does following transcervical AI.

scholarly journals The Effect of Vertical Sleeve Gastrectomy on a Rat Model of Polycystic Ovarian Syndrome

Endocrinology ◽  
2011 ◽  
Vol 152 (10) ◽  
pp. 3700-3705 ◽  
Author(s):  
Hilary E. Wilson-Pérez ◽  
Randy J. Seeley
Keyword(s):  
Bariatric Surgery ◽  
Weight Loss ◽  
Body Weight ◽  
Glucose Tolerance ◽  
Polycystic Ovarian Syndrome ◽  
Vertical Sleeve Gastrectomy ◽  
Metabolic Disturbances ◽  
Menstrual Dysfunction ◽  
Estrous Cyclicity ◽  
Ovarian Syndrome

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder of women of reproductive age. Although some of the primary symptoms of PCOS are reproductive abnormalities, including hyperandrogenism, menstrual dysfunction, and hirsutism, other metabolic disturbances are also common, including obesity and insulin resistance. Women with PCOS who have undergone weight-loss bariatric surgery have reported surprising postoperative benefits beyond weight loss, including resolution of menstrual dysfunction and improvement of hirsutism. Here, we use a chronic dihydrotestosterone (DHT) exposure model of PCOS in female rats and investigate the efficacy of a specific type of bariatric surgery, namely vertical sleeve gastrectomy (VSG), to resolve the reproductive and metabolic disturbances induced by DHT treatment. We find that VSG causes loss of body weight and body fat in DHT-treated rats but does not improve glucose tolerance or restore estrous cyclicity. Although human PCOS patients have shown decreased androgen levels after bariatric surgery, the chronic nature of DHT administration in this rat model both before and after VSG renders this effect impossible in this case. Therefore, the lack of improvement in glucose tolerance and estrous cyclicity may implicate a direct effect of androgen knockdown as a mechanism for the improvements seen in human PCOS patients after bariatric surgery. In addition, the dissociation of body weight loss without improved glucose tolerance suggests that glucose intolerance may be a body weight-independent phenomenon in women with PCOS.

Sign in / Sign up

Export Citation Format

Share Document