Bilateral maintenance of rabbit corpora lutea by the feto-placental unit

1986 ◽  
Vol 109 (1) ◽  
pp. 107-110
Author(s):  
R. A. Nowak ◽  
J. S. Klein ◽  
D. M. Pulido ◽  
J. M. Bahr
Keyword(s):  
Corpus Luteum ◽  
Normal Serum ◽  
High Rate ◽  
Corpora Lutea ◽  
Serum Progesterone ◽  
Blood Samples ◽  
Treatment Groups ◽  
Pregnancy Failure ◽  
Group I ◽  
Group Ii

ABSTRACT The present study was undertaken to determine (1) whether the rabbit feto-placental unit maintains corpora lutea systematically and/or locally and (2) the interrelationships between conceptus number, luteal weight, luteal progesterone concentrations and serum progesterone levels. Thirty-three does were divided into the following treatment groups: (I) bilaterally pregnant, two ovaries; (II) unilaterally pregnant, two ovaries; (III) bilaterally pregnant, one ovary; (IV) unilaterally pregnant, one ovary, contralateral and (V) unilaterally pregnant, one ovary, ipsilateral. Blood samples were obtained from all rabbits on days 6, 9, 12, 15, 18 and 21 post coitum. Does were killed on day 21, and the percentage of viable fetuses, fetal weights, and luteal weights recorded. Blood samples and corpora lutea were analysed for progesterone. Serum progesterone levels were similar for all groups until day 9 post coitum. Levels in groups III, IV and V declined significantly between days 9 and 12 following removal of one ovary at day 9. Fetal viability, fetal weights and luteal progesterone concentrations did not differ among any of the groups. Luteal weights did not differ among groups I, III, IV and V, but luteal weights of animals in group II were lower than those of group I (P<0·05). Ratios of viable fetuses to number of corpora lutea ranged from 1:11–10:5. No differences were observed in serum progesterone, luteal weights or luteal progesterone concentrations among animals with two conceptuses and those with seven or more, but serum progesterone levels in does with only one conceptus were lower than those in does with more (P<0·05). These results indicate that the feto-placental unit maintains corpora lutea systemically and that the high rate of pregnancy failure by day 21 in does with only one conceptus is due to the inability of a single conceptus to maintain normal serum progesterone levels even though the corpus luteum weight is not affected. J. Endocr. (1986) 109, 107–110

Serum Endocrine Profile in Relation to Estrus Synchronization in Surti Does

2018 ◽  
Vol 13 (03) ◽  
Author(s):  
M. M. Chaudhary ◽  
C. T. Khasatiya ◽  
S. B. Patel ◽  
S. S. Chaudhary ◽  
V. B. Atara ◽  
...  
Keyword(s):  
Jugular Vein ◽  
Estrus Synchronization ◽  
Progesterone Concentration ◽  
Serum Progesterone ◽  
Blood Samples ◽  
Group Iii ◽  
Group I ◽  
Endocrine Profile ◽  
Group Ii ◽  
And Control

The serum progesterone and estradiol profiles during synchronization of estrus by buck effect and PGF2α treatments were monitored in Surti does. Total eighteen non-pregnant does selected were evenly divided into 3 groups, 6 does in each group. The does of Group I were teased with a sexuallyactive- apronized buck; and those of Group II were treated with PGF2α, i.e., Inj. Lutalyse® @ 7.5 mg/doe IM twice 11 days apart, while the Group III served as untreated control. Blood samples were collected from all the animals on day 0 (before 1st PGF2α injection), 3rd day (during treatment), 11th day (before 2nd PGF2α injection), 14th day (after treatment) and 40th day (post-service) by jugular vein puncture. The serum separated was stored at -20°C till further analysis. In all the three groups, 83.33% does, conceived at first service in the sampling cycle. The overall mean serum progesterone concentration of Group I does (5.82±0.72 ng/ml) was significantly higher (p less than 0.01) as compared to Group II (2.93±0.38 ng/ml) and III (2.88±0.30 ng/ml). Similarly, the overall mean serum progesterone concentration of Surti does on day 0 (2.65±0.46 ng/ml), 3rd (2.56±0.80 ng/ml), 11th (4.45±0.84 ng/ml) and 14th (3.40±0.63 ng/ml) did not differ significantly, but the overall mean level at day 40 (6.31±0.45 ng/ml) was significantly (p less than 0.01) higher, because most of animals became pregnant at that time. The overall mean serum oestradiol-17β levels of Group I (24.40±2.98 pg/ ml) was significantly higher (p less than 0.01) than in Group II (15.77±1.77 pg/ml) and III (12.21±1.45 pg/ ml). On the other hand, the overall mean serum oestradiol-17β levels of Surti does on day 0 (12.89±1.21 pg/ml), 3rd (15.84±1.74 pg/ml), 11th (14.81±1.96 pg/ml), 14th (22.15±2.97 pg/ml) and 40th (21.64±5.16 pg/ml) did not differ significantly (p>0.05) and the slightly higher overall mean level found at 40th day might be the influence of the non-pregnant does at first service in the cumulative animals. The hormonal profile reflected the initiation of cyclicity and establishment of pregnancy in treated and control animals.

57 DIETARY CLA SUPPLEMENTATION AFFECTS LUTEAL GENE EXPRESSION AND PERIPHERAL BLOOD PROGESTERONE CONCENTRATION IN CATTLE

2012 ◽  
Vol 24 (1) ◽  
pp. 140
Author(s):  
H. Stinshoff ◽  
E. Onnen-Lübben ◽  
S. Wilkening ◽  
A. Hanstedt ◽  
H. Bollwein ◽  
...  
Keyword(s):  
Gene Expression ◽  
Corpus Luteum ◽  
Control Group ◽  
Progesterone Concentration ◽  
Blood Samples ◽  
Oral Supplementation ◽  
Group I ◽  
Pregnancy Status ◽  
Gene Transcripts ◽  
Group Ii

Shortly after parturition the metabolic situation of high-yielding dairy cows is often dominated by a negative energy balance. These effects affect the whole animal and may especially be detected in the reproductive tract, where they result in reduced fertility. An oral supplementation with dietary fats is often used to counteract by reducing milk fat content and, thus, supplying the individual animal with an increased amount of energy. The focus of the present study was to analyse the effects of an oral supplementation with conjugated linoleic acids (CLA) on corpus luteum (CL) function. Healthy Holstein-Friesian cows and heifers were randomly allocated to 2 treatment groups (Group 1: 50 g of CLA day–1 per animal, 2 heifers, 6 cows; Group 2: 100 g of CLA day–1 per animal, 2 heifers, 6 cows) and 1 control group (Ctl; 0 g of CLA day–1 per animal, 3 heifers, 4 cows). Feeding of the supplement began shortly after calving. After calving, all animals were subjected to a standard synchronisation protocol and experienced AI on Day 59 ± 3. Following AI, transvaginal biopsies of the corpus luteum were obtained of pregnant (Group I: n = 4; Group II: n = 4; Ctl: n = 4) and nonpregnant (Group I: n = 4; Group II: n = 4; Ctl: n = 3) animals on Days 6, 13 and 20 post-AI. Animals deemed pregnant on Day 28 were again biopsied on Day 42. Additionally, blood samples were taken from the vena sacralis mediana at the time of each biopsy. The biopsies were analysed regarding the relative abundance of 8 gene transcripts (VEGF, ECE1, PLA2G4A, PTGS2, PTGFR, PPARG, STAR and HSD3B1) via RT-qPCR. Blood samples were analysed for their concentration of progesterone through a radioimmunoassay (RIA). Statistical analysis for both datasets was performed via a 3-way ANOVA with adjoining Tukey test. The expression of 7 of these genes was affected by 1, 2, or all 3 of the following factors: day of cycle (VEGF, ECE1, PLA2G4A, PTGFR, STAR and HSD3B1), pregnancy status (ECE1, PTGFR and HSD3B1) and CLA supplementation (ECE1, PTGS2, PTGFR, STAR and HSD3B1). The effects of the CLA supplementation could be seen as a down-regulation in the mentioned gene transcripts. Progesterone concentrations differed significantly in dependency of the pregnancy status (significantly higher in pregnant vs nonpregnant individuals) of the animals, as well as during the days of the oestrous cycle (physiological progesterone curve with highest values on Day 13 of these samples). An effect of the oral supplementation with CLA could be detected during the early luteal phase (Day 6) where animals that had received 100 g of CLA day–1 had a significantly lower blood progesterone concentration than those receiving 50 g of CLA day–1 or no CLA. In conclusion, dietary CLA supplementation has an effect on luteal gene expression and functionality. The authors thank the DFG (German Research Foundation) for their financial support (PAK286/1; WR154/1-1).

scholarly journals Changes in serum cortisol concentrations in West African Dwarf (WAD) bucks during electroejaculation

2021 ◽  
Vol 39 (1) ◽  
pp. 31-36
Author(s):  
J. O Daramola ◽  
A. A Adeloye ◽  
I. A Balogun ◽  
M. B Yousuf ◽  
A. O. Olatunde ◽  
...  
Keyword(s):  
Ambient Temperature ◽  
Serum Cortisol ◽  
West African ◽  
Blood Samples ◽  
Late Afternoon ◽  
Treatment Groups ◽  
West African Dwarf ◽  
Group I ◽  
Cortisol Levels ◽  
Group Ii

Changes in the concentration of serum cortisol in blood samples of twenty healthy West African Dwarf (WAD) bucks were determined during electro-ejaculation. The animals were randomly assigned to one of two treatment groups. Group I consisted of bucks that had rectal probe inserted but were not electroejaculated (NEE), and group II consisted of bucks that were electroejaculated (EE) in the morning (0900hr), afternoon (1400hr) and late afternoon (1800hr). The results showed that serum cortisol values found in both groups were similar (P>0.05). Increase in cortisol levels were observed (P<0.05) in the afternoon in both EE and NEE animals in comparison with morning and late afternoon. The findings of this study indicate that the increase observed in cortisol concentrations in the afternoon in both groups reflects stress stimuli due to slight increase in ambient temperature.

Different Treatment Protocols of Retained Fetal Membranes and its Effect on Serum Profile, Uterine Involution and Postpartum Fertility in Cows

2019 ◽  
Vol 14 (04) ◽  
Author(s):  
A. I. Shah ◽  
D. M. Patel ◽  
N. P. Sarvaiya ◽  
S. P. Madhira
Keyword(s):  
Group Iv ◽  
Fetal Membranes ◽  
Serum Progesterone ◽  
Group V ◽  
Manual Removal ◽  
Uterine Involution ◽  
Group I ◽  
Medicinal Treatment ◽  
Group Ii ◽  
Postpartum Estrus

This study was undertaken on 36 freshly calved cows randomly divided into 6 equal groups under field conditions. Cows of group-VI that shed placenta within 8-12 hours postpartum naturally served as healthy control. The cows with retained fetal membranes (RFM, n = 18) for more than 12 hrs were managed either by manual removal of placenta without antibiotics (group-I), parenteral antibiotic (Ceftiofur 1 g i/m) for three consecutive days (group-II) or a combination of both (group-III). In group-IV and group-V, cows were administered with Inj. Oxytocin @ 50 IU i/m and Inj. Dinoprost tromethamine (PGF2α) @ 25 mg i/m, respectively, immediately after parturition and time of placental shedding was recorded. The overall prevalence of Brucellosis by RBPT was found to be 5.55 % amongst these 36 animals. The placental expulsion in groups following medicinal treatment was found to be 50 (3/6) % in Ceftiofur alone by 3 days (group-II), and 66.67 (4/6) % in Oxytocin (group-IV) and 100 (6/6) % in PGF2α inj. (group-V) groups within 12 hrs. The time of uterine involution in groups I to VI was found to be 42.00 ± 1.94, 39.50 ± 0.99, 40.67 ± 1.39, 38.33 ± 1.55, 37.50 ± 1.02 and 37.33 ± 1.76 days, respectively, while the interval for the appearance of first postpartum estrus was 54.83 ± 2.06, 51.00 ± 1.05, 52.17 ± 1.96, 50.17 ± 2.03, 48.67 ± 1.90 and 49.17 ± 1.55 days, respectively, which did not vary statistically. The mean serum progesterone profile obtained on day 0 and day 21 postpartum was statistically non-significant between groups. However, it was significantly (p less than 0.05) lower on day 0 as compared to day 21 in group-I, II and VI. The levels on day 0 coincided with the time of blood sampling after calving. The high level of serum P4 on day 0 in group-IV and V could be due to sampling immediately after calving. The serum calcium and phosphorus levels were significantly(p less than 0.05) lower on day 0 than on day 21, but not the magnesium. The group effect was however non-significant for any of three minerals. It was observed that manual removal of RFM without parenteral antibiotics, resulted in puerperal metritis, cervicitis, pyometra which ultimately resulted into delayed uterine involution, delayed first postpartum estrus and thus, reduced the postpartum reproductive efficiency. It was inferred that the PGF2α and Oxytocin injections could be used as a treatment of choice for prevention of RFMs in cattle.

scholarly journals Management of patients with rectocele, multiple pelvic floor dysfunctions and obstructed defecation syndrome

2012 ◽  
Vol 49 (2) ◽  
pp. 135-142 ◽  
Author(s):  
Sthela Maria Murad-Regadas ◽  
Francisco Sergio P. Regadas ◽  
Lusmar Veras Rodrigues ◽  
Graziela Olivia da Silva Fernandes ◽  
Guilherme Buchen ◽  
...  
Keyword(s):  
Obstructed Defecation ◽  
Mucosal Prolapse ◽  
Clinical Treatment ◽  
Group Iii ◽  
Treatment Groups ◽  
Obstructed Defecation Syndrome ◽  
Group I ◽  
Grade Ii ◽  
Group Ii ◽  
Grade Iii

CONTEXT: Management of patients with obstructed defecation syndrome is still controversial. OBJECTIVE: To analyze the efficacy of clinical, clinical treatment followed by biofeedback, and surgical treatment in patients with obstructed defecation, rectocele and multiple dysfunctions evaluated with echodefecography. METHODS: The study included 103 females aged 26-84 years with obstructed defecation, grade-II/III rectocele and multiple dysfunctions on echodefecography. Patients were distributed into three treatment groups and constipation scores were assigned. Group I: 34 (33%) patients with significant improvement of symptoms through clinical management only. Group II: 14 (14%) with improvement through clinical treatment plus biofeedback. Group III: 55 (53%) referred to surgery due to treatment failure. RESULTS: Group I: 20 (59%) patients had grade-II rectocele, 14 (41%) grade-III. Obstructed defecation syndrome was associated with intussusception (41%), mucosal prolapse (41%), anismus (29%), enterocele (9%) or 2 dysfunctions (23%). The average constipation score decreased significantly from 11 to 5. Group II: 11 (79%) grade-II rectocele, 3 (21%) grade-III, associated with intussusception (7%), mucosal prolapse (43%), anismus (71%) or 2 dysfunctions (29%). There was significant decrease in constipation score from 13 to 6. Group III: 8 (15%) grade-II rectocele, 47 (85%) grade-III, associated with intussusception (42%), mucosal prolapse (40%) or 2 dysfunctions (32%). The constipation score remained unchanged despite clinical treatment and biofeedback. Twenty-three underwent surgery had a significantly decrease in constipation score from 12 to 4. The remaining 32 (31%) patients which 22 refused surgery, 6 had low anal pressure and 4 had slow transit. CONCLUSIONS: Approximately 50% of patients with obstructed defecation, rectocele and multiple dysfunctions presented a satisfactory response to clinical treatment and/or biofeedback. Surgical repair was mainly required in patients with grade-III rectocele whose constipation scores remained high despite all efforts.

scholarly journals Impact of environmental temperature to the content of protein on fresh, cold and frozen meat

2021 ◽  
Vol 922 (1) ◽  
pp. 012061
Author(s):  
C D Iskandar ◽  
Zainuddin
Keyword(s):  
Protein Content ◽  
Environmental Temperature ◽  
Quadriceps Muscle ◽  
C Protein ◽  
Group Iii ◽  
Treatment Groups ◽  
Protein Levels ◽  
Group I ◽  
Group Ii

Abstract This study aims to determine the amount of protein content in Aceh cattle beef in the quadriceps muscle (chuck) and to find out the best storage between cold and frozen to protein levels of beef. This study used 10 samples of Aceh cattle beef parts of the quadriceps (chuck) which were divided into 3 treatment groups, group I meat was treated in fresh condition, Group II meat was treated in cold at 8 °C and Group III meat will be treated in frozen at -19 °C. Protein content in meat was analysed by the Independent Samples Test. The results showed that the amount of Aceh beef protein in the quadriceps (chuck) in fresh; 15, 47%, cold 10, 20% and frozen; 9, 97. It was concluded that storing meat in cold and frozen ways is affect the protein content. Frozen meat storage is better to keep protein content than Cold meat storage.

PROGESTERONE AND LUTEINIZING HORMONE CONCENTRATION IN SERUM OF PREGNANT GILTS ON DIFFERENT LEVELS OF FEED CONSUMPTION

1980 ◽  
Vol 60 (4) ◽  
pp. 877-884 ◽  
Author(s):  
G. W. DYCK ◽  
W. M. PALMER ◽  
S. SIMARAKS
Keyword(s):  
Luteinizing Hormone ◽  
Feed Consumption ◽  
Blood Collection ◽  
Corpora Lutea ◽  
Serum Progesterone ◽  
Treatment Groups ◽  
Fetal Survival ◽  
Serum Lh ◽  
Luteinizing Hormone Concentration ◽  
Collection Period

Blood serum progesterone (P) and luteinizing hormone (LH) were determined in 31 Lacombe gilts at a 3- to 4-day interval from 10 to 56 days of pregnancy. They were fed 1.50 (L), 2.25 (M) or 3.00 (H) kg of a 16% protein diet/day and had average daily gains of 0.16 ± 0.02 (SE), 0.36 ± 0.02 and 0.60 ± 0.02 kg/day, respectively. All gilts were slaughtered between 59 and 61 days of pregnancy. The treatments had no effect on the number of corpora lutea (13.9 ± 0.4 CL), number of fetuses (10.8 ± 0.6), fetal survival (78.3 ± 3.7%) or mean fetal weight (122 ± 3 g). The gilts on the H level of feeding had heavier (P < 0.05) ovaries (18.4 ± 0.8 g) than those of the L (15.6 ± 0.7 g) or M (15.6 ± 0.8 g) treatment groups. Serum P concentration declined during the blood collection period (b = −0.12, −0.06 and −0.09 for the L, M and H groups, respectively). Serum P concentrations also were different (P < 0.01) for each treatment group (L, 16.7 ± 0.3; M, 13.8 ± 0.03; and H, 11.8 ± 0.3 ng/mL). The serum LH concentration was greater (P < 0.05) for the M gilts (0.63 ± 0.05 ng/mL) than for the L (0.37 ± 0.04 ng/mL) or H (0.47 ± 0.05 ng/mL) gilts. Significant correlations were observed among the number of fetuses, number of CL, ovarian weight and P for the L gilts, and the number of fetuses and CL for the M gilts. These results suggest that growth rate is a major contributor to differences in blood P and LH concentrations during pregnancy and that the animal adjusts its P and LH production to its specific requirements for the maintenance of pregnancy.

IN-VITRO STEROIDOGENESIS OF NEWLY FORMED CORPORA LUTEA AND THE NON-LUTEAL OVARY IN THE RAT, RABBIT, HAMSTER AND GUINEA-PIG

1980 ◽  
Vol 84 (1) ◽  
pp. 101-108 ◽  
Author(s):  
P. F. TERRANOVA ◽  
S. K. SAIDAPUR ◽  
G. S. GREENWALD
Keyword(s):  
Guinea Pig ◽  
Corpus Luteum ◽  
Ovarian Function ◽  
Serum Testosterone ◽  
The Other ◽  
Corpora Lutea ◽  
Serum Progesterone ◽  
Antral Follicles ◽  
Baseline Levels

The steroidogenic abilities of the newly formed corpus luteum (8–10 h after ovulation) and the non-luteal ovary were compared in the guinea-pig, hamster, rabbit and rat using an invitro incubation technique. Histologically, newly formed rat corpora lutea (CL) were highly luteinized whereas the CL of the rabbit and guinea-pig were only partially luteinized. The CL of the hamster showed the least amount of luteinization. Serum progesterone was highest in the rat (18 ± 3 (s.e.m.) ng/ml). In the hamster, it was about 8 ng/ml, whereas in the rabbit and guinea-pig it was about 1 ng/ml. Serum androstenedione ranged between 0·5 and 1 ng/ml. Serum testosterone was lowest in the hamster (60 pg/ml) and highest in the rabbit (470 pg/ml), whereas in the rat and guinea-pig, testosterone levels were similar (about 240 pg/ml). Serum oestrogens were at baseline levels in all species. The CL of the rat exhibited considerably greater steroidogenic ability than the CL of the other species, producing 70 ± 6 ng progesterone/mg per h, 215 ± 14 pg androstenedione/mg per h, 49 ± 3 pg testosterone/mg per h, 3 pg oestrone/mg per h and 1 pg oestradiol/mg per h. Rabbit CL produced only progesterone (7 ± 2 ng/mg per h). Newly formed hamster CL produced none of the above steroids. In general, the ability of the CL to produce progesterone in vitro correlated with the degree of luteinization found by histological observation. Guinea-pig CL were embedded deeply in the ovary and could not be obtained without damage. Consequently, a portion of the ovary containing a corpus luteum was incubated. There was no difference in the steroid production by this portion of the ovary compared with the non-luteal ovary. The non-luteal ovary of the rat produced the highest amount of progesterone (10 ± 2 ng/mg per h). The guinea-pig non-luteal ovary produced about 5 ± 2 ng progesterone/mg per h, whereas the non-luteal ovary of the rabbit did not produce any. On the other hand, the hamster non-luteal ovary lost progesterone. Non-luteal ovaries from all species produced androgens. The non-luteal ovary of the guinea-pig contained especially large numbers of atretic antral follicles. The guinea-pig non-luteal ovary produced extremely large amounts of androstenedione (1110 ± 210 pg/mg per h) and testosterone (606 ± 154 pg/mg per h) compared with the amounts produced by the non-luteal ovary of the rat, hamster and rabbit. In the non-luteal ovary, interstitium and atretic antral follicles are the probable source of androgens. Oestrogen production by the non-luteal ovary was at baseline levels in the four species studied correlating with the absence of healthy antral follicles. The results indicate the extreme species differences that exist in ovarian function in the early postovulatory period.

FAILURE OF THE TRH TEST TO PREDICT THE CLINICAL COURSE OF PATIENTS IN REMISSION AFTER ANTITHYROID DRUG THERAPY FOR GRAVES' DISEASE

1979 ◽  
Vol 90 (1) ◽  
pp. 18-22
Author(s):  
W. J. Irvine ◽  
R. S. Gray ◽  
A. D. Toft ◽  
J. Seth ◽  
E. H. D. Cameron
Keyword(s):  
Drug Therapy ◽  
Clinical Course ◽  
Antithyroid Drug ◽  
Normal Serum ◽  
Antithyroid Drugs ◽  
Trh Test ◽  
Group I ◽  
Antithyroid Drug Therapy ◽  
Group Ii ◽  
Serum Tsh

ABSTRACT In an attempt to assess the predictive value of the TRH test in patients in remission after stopping antithyroid drugs for thyrotoxicosis, 11 euthyroid patients with a subnormal (group I) and 23 euthyroid patients with a normal serum TSH response to TRH (group II) were followed-up for one year. The mean ± se intervals since the withdrawal of drug therapy were 23.2 ±1.6 and 20.4 ± 0.7 months, respectively, at the outset of the study. Five patients (45 %) from group I and 7 patients (30 %) from group II relapsed during the period of observation. In addition, a change from a subnormal to a normal serum TSH response to TRH and vice versa occurred in some patients. It is not possible to predict by means of the TRH test the subsequent clinical course of patients in remission following antithyroid drug therapy.

EFFECT OF INTRA-UTERINE FOREIGN BODIES AND OF PROSTAGLANDIN ADMINISTRATION ON PROGESTERONE SECRETION DURING THE OESTROUS CYCLE OF THE GUINEA-PIG

1976 ◽  
Vol 70 (1) ◽  
pp. 39-45 ◽  
Author(s):  
F. R. BLATCHLEY ◽  
B. T. DONOVAN
Keyword(s):  
Guinea Pig ◽  
Corpus Luteum ◽  
Foreign Bodies ◽  
Glass Beads ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Blood Samples ◽  
Progesterone Secretion ◽  
Prostaglandin F

SUMMARY The response of the guinea-pig corpus luteum to the luteolytic influence of glass beads placed in the uterus, or to prostaglandin administration, was followed by assay of the progesterone content of blood samples collected daily. Following the introduction of glass beads into the uterus early in the cycle, the secretion of progesterone was curtailed. Treatment with prostaglandin F2α over days 4–6 or 6–8 of the cycle temporarily depressed progesterone release without shortening the life of the corpora lutea. When the drug was administered over days 8–10, 10–12 or 12–14 the depression in progesterone was not followed by any recovery. These observations indicate that the response of the corpora lutea to a luteolytic influence changes during the oestrous cycle.

Sign in / Sign up

Export Citation Format

Share Document