FSH and LH receptor concentrations in large ovarian follicles of beef cows in high and low levels of body condition at nine weeks post partum

1992 ◽  
Vol 4 (5) ◽  
pp. 515 ◽  
Author(s):  
SM Rhind ◽  
TA Bramley ◽  
IA Wright ◽  
SR McMillen
Keyword(s):  
Luteinizing Hormone ◽  
Body Condition ◽  
Post Partum ◽  
Follicle Stimulating Hormone ◽  
Beef Cows ◽  
Ovarian Follicles ◽  
Lh Receptor ◽  
The Mean ◽  
Low Levels ◽  
Body Condition Scores

An experiment was conducted to determine whether or not the effect of body condition at parturition, and thereafter, on the duration of the post-partum anoestrous period was mediated through differences in gonadotrophin receptor concentrations in the ovarian follicles. Two groups of cows were fed to achieve body condition scores of > or = 2.75 (H; n = 14) or < or = 2.00 (L; n = 15) at parturition (this had led to differences in the duration of post-partum anoestrus in previous experiments) and then fed to maintain liveweight and condition until ovariectomy at nine weeks post partum. There was no effect of body condition on the mean (+/- s.e.) number of large (> or = 8 mm diameter) follicles per cow (3.0 +/- 0.27) but a greater proportion of the follicles of H cows, compared with L cows, was oestrogenic (secreting > 250 pg oestradiol h-1 in culture) (0.75 v. 0.5; chi 2 = 3.40; P = 0.06). Mean concentrations (pg hormone bound per mg protein) of follicle stimulating hormone (FSH) receptors in both granulosa (H, 157.3; L, 136.6; standard error of difference (s.e.d.) = 27.2) and thecal tissue (H, 4.14; L, 4.35; s.e.d. = 1.66) were similar for H and L cows. There was no difference associated with treatment in luteinizing hormone (LH) receptor concentrations in either granulosa (H, 40.3; L, 37.2; s.e.d. = 6.67) or thecal tissue (H, 48.9; L, 48.0; s.e.d. = 6.03). The concentration of FSH receptors in granulosa tissue was lower in non-oestrogenic follicles than in oestrogenic follicles (80.0 v. 188.1; s.e.d. = 40.4; P < 0.01).

scholarly journals Effect of GnRH pulse infusion on LH profiles and ovarian follicle populations at 7 weeks post-partum in beef cows in different body conditions

1992 ◽  
Vol 1992 ◽  
pp. 196-196
Author(s):  
L. Pinto Andrade ◽  
S.M. Rhind ◽  
L.A. Wright ◽  
S.R. McMillen ◽  
T.K. Whyte
Keyword(s):  
Body Condition ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Follicular Development ◽  
Beef Cows ◽  
Ovarian Follicles ◽  
Normal Process

Previous studies have indicated that low body condition (LBC) at calving increases the duration of the postpartum anoestrous period in suckling beef cows (Henricks et al 1986; Wright et al 1987). The results of recent experiments also suggest that animals in LBC have a reduced incidence of LH pulses (Wright et al 1990) which is associated with a reduction in the incidence of large, oestrogenic, potentially ovulatory ovarian follicles (Prado et al 1990).An experiment was designed to determine a) whether or not the normal process of follicular development can be accelerated in LBC cows by infusion of pulses of GnRH, so that their postpartum anoestrous period was as short as that of cows in HBC and b) the effect of GnRH pulse infusions on associated gonadotropin profiles.

Influence of nutrition on pre-partum plasma levels of progesterone and total oestrogens and post-partum plasma levels of luteinizing hormone and follicle stimulating hormone in suckling cows

1983 ◽  
Vol 37 (1) ◽  
pp. 89-96 ◽  
Author(s):  
D. Gauthier ◽  
M. Terqui ◽  
P. Mauleon
Keyword(s):  
Luteinizing Hormone ◽  
Plasma Levels ◽  
Post Partum ◽  
Control Diet ◽  
Follicle Stimulating Hormone ◽  
Control Group ◽  
Luteinizing Hormone Concentration ◽  
The Mean ◽  
Daily Gain ◽  
Stimulating Hormone

ABSTRACTTwo groups of suckling Charolais cows were fed at different levels of nutrition from 70 days before the estimated date of calving until 45 days after calving, to study the effects of reduced dietary intake on pre-partum plasma levels of progesterone and total oestrogens (conjugated + unconjugated) and post-partum plasma levels of luteinizing hormone and follicle stimulating hormone. Eight control cows received a ration containing the Institut National de la Recherche Agronomique's recommendations for all nutrients, while 10 cows received a restricted diet which supplied approximately three-quarters of the recommended amounts for energy and nitrogen.The mean weight of the two groups of cows was similar at the beginning of the experiment but the restricted group had a significantly lower weight just before calving than the control group (678 v. 766 kg; P < 0·05).After calving, cows ont he low diet had a weight loss of 600 g/day, while those on the control diet gained 300 g/day. During the last 45 days of pregnancy underfeeding did not significantly affect oestrogen levels, but progesterone levels increased proportionally by 0·24 (P < 0·01).During the first 45 days of lactation underfeeding decreased the number of cows showing oestrus (0/10 v. 4/8) and significantly decreased both luteinizing hormone and follicle stimulating hormone levels at 5, 15 and 30 days post partum.Furthermore, the correlation between mean daily gain (0 to 45 days post partum) and luteinizing hormone concentration on day 30 was highly significant (r = 0·58; P < 0·01; no. = 19). These results suggest that the delay of the first post-partum ovulation in the underfed cow is due to low gonadotropin levels.

Ovarian follicle populations, steroidogenicity and micromorphology at 5 and 9 weeks post partum in beef cows in two levels of body condition

1990 ◽  
Vol 51 (1) ◽  
pp. 103-108 ◽  
Author(s):  
R. Prado ◽  
S. M. Rhind ◽  
I. A. Wright ◽  
A. J. F. Russel ◽  
S. R. McMillen ◽  
...  
Keyword(s):  
Body Condition ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Live Weight ◽  
Beef Cows ◽  
Lower Number ◽  
The Body ◽  
Lh Pulsatility ◽  
Body Condition Scores

ABSTRACTThe effect of body condition at calving on ovarian follicle characteristics during post-partum anoestrus was studied in 38 suckling Blue-Grey cows with mean body-condition scores of 2·80 (s.e. 0·05) (H) or 2·35 (s.e. 0·05) (L) at calving and fed so that they maintained live weight and body condition during lactation. Cows of each level of body condition were ovariectomized at either 5 or 9 weeks after calving and follicles ≥3 mm in diameter were dissected out and incubated in a medium (Medium 199) for 2 h. Follicle incubates were assayed for progesterone, testosterone and oestradiol. L cows had fewer follicles ≥3 mm in diameter than H cows (24·1 v. 44·9; P < 0·05) at 5 weeks post partum due to a lower number of small (3 to 4 mm) follicles (12·9 v. 30·6; P < 0·05). At 9 weeks there was no effect of body condition on mean numbers of follicles (38·1 v. 40·4; P > 0·05). The proportions of healthy, intermediate and atretic follicles in all cows were 0·35, 0·20 and 0·45 respectively; these proportions were not affected by body condition or time of ovariectomy. Body condition did not affect the overall mean capacity of the cultured follicles to produce oestradiol or progesterone in vitro but testosterone production was higher in follicles from H than L cows (6406 v. 5206 pg/h; P < 0·05). However, at 9 weeks post partum a greater proportion of H than L cows had a large (>8 mm), healthy, highly oestrogenic follicle (4/8 v. 1/7; P = 0·18).At 9 weeks post partum, the four large, healthy, oestrogen-active follicles (those secreting >250 pg/h) from H cows were approximately 11-fold more oestrogenic than the single comparable follicle from L cows (7100 v. 635 pg/h; P > 0·05). There was little difference at week 5 post partum: 3288 and 2785 pg/h (P > 0·05) for H and L cows respectively. Oestrogen-active follicles from H cows were significantly more oestrogenic at 9 than 5 weeks post partum (5807 v. 3021 pg/h; P < 0·05). The results suggest that the body condition-related reduction in the number and steroidogenic capacity of large oestrogenic follicles in post-partum cows may be associated with a reduction in LH pulsatility.

Effects of body condition at calving and feeding level after calving on LH profiles and the duration of the post-partum anoestrous period in beef cows

1992 ◽  
Vol 55 (1) ◽  
pp. 41-46 ◽  
Author(s):  
I. A. Wright ◽  
S. M. Rhind ◽  
T. K. Whyte ◽  
A. J. Smith
Keyword(s):  
Body Condition ◽  
Post Partum ◽  
Live Weight ◽  
Pulse Amplitude ◽  
Beef Cows ◽  
Pulse Frequency ◽  
Metabolizable Energy ◽  
Feeding Level ◽  
Effect Of Feeding ◽  
Body Condition Scores

AbstractAn experiment was conducted to examine the effects of body condition at calving and feeding level post partum on the duration of the post-partum anoestrous period in beef cows. Forty-seven cows were used in each of 2 years. Cows were fed differentially before calving to achieve two levels of body condition at calving in November and December and were then fed at one of two levels of feeding post partum in a 2 × 2 factorial experiment. At calving, mean body condition scores were 2·85 (F) and 2·23 (T) (P < 0·001) while live weights were 521 kg and 457 kg (P < 0·001) for F and T cows respectively. After calving metabolizable energy intakes were 111 and 118 MJ/day (H) or 56 and 64 MJ/day (L) in years 1 and 2 respectively. The H cows maintained live weight during the first 61 days of lactation while the L cows lost live weight (0·0 v. -1·1 kg/day, P < 0·001). The number of cows still acyclic on 1 May each year was higher (P < 0·01) on the TL treatment (10/24) compared with the other treatment combinations (FH: 2/22; FL: 5/22; TH: 2/24). The effect of level of feeding on the duration of the anoestrous period was significant in the T cows (89 v. 116 days for TH and TL cows respectively; P < 0·01) but not in the F cows (80 v.89 days for the FH and FL cows respectively; P > 0·05). At 3 weeks post partum LH pulse frequency was higher in F than in T cows and tended to be higher in H than in L cows. At 6 and 9 weeks post partum LH pulse frequency was higher in H than L cows. LH pulse amplitude was higher in F than T cows at 3 weeks post partum and tended to be higher at 6 weeks post partum. It is concluded that both body condition at calving and feeding level after calving influence the duration of the post-partum anoestrous period with the effect of feeding level being particularly pronounced in thin cows.

A note on the effects of pattern of food intake and body condition on the duration of the post-partum anoestrous period and LH profiles in beef cows

1992 ◽  
Vol 54 (1) ◽  
pp. 143-146 ◽  
Author(s):  
I. A. Wright ◽  
S. M. Rhind ◽  
T. K. Whyte
Keyword(s):  
Food Intake ◽  
Luteinizing Hormone ◽  
Body Condition ◽  
Post Partum ◽  
Beef Cows ◽  
Peripheral Circulation ◽  
Pulse Frequency ◽  
Metabolizable Energy ◽  
Unit Increase ◽  
Feeding Regimes

An experiment was conducted to determine the effect of level and pattern of food intake in post-partum beef cows on the length of the post-partum anoestrous period and associated luteinizing hormone profiles. Forty-six multiparous cows were allocated at calving to one of three feeding regimes: 55 MJ metabolizable energy (ME) per day throughout (LL), 145 M] ME per day throughout (HH), or 55 M] ME per day until 6 weeks post partum and then 145 M] ME per day thereafter (LH). The duration of the post-partum anoestrous period was assessed from plasma progesterone profiles. Luteinizing hormone profiles in the peripheral circulation were determined at weeks 3, 6, 8 and 11 post partum from samples collected every 20 min for 10 h.Feeding regime had no effect on either the length of the post-partum anoestrous period, being 99, 89 and 91 (s.e.d. 12·2) days for the LL, LH and HH cows respectively, or on any aspect of luteinizing hormone pulsatility. Body condition at calving was negatively correlated with the duration of the post-partum anoestrous period, each unit increase in body condition at calving being associated with a decrease in the post-partum anoestrous period of 86 (s.e. 21·8) days. Luteinizing hormone pulse frequency at 6 weeks post partum was positively correlated with body condition at calving.This experiment confirms the importance of body condition at calving in influencing the duration of the post-partum anoestrous period and indicates that level and pattern of feeding post partum has little effect when cows calve at a body condition of approximately 2·25.

Pattern of plasma progesterone, oestradiol-17β, luteinizing hormone and androgen in non-pregnant buffalo (Bubalus bubalis)

1982 ◽  
Vol 100 (2) ◽  
pp. 279-284 ◽  
Author(s):  
R. C. Arora ◽  
R. S. Pandey
Keyword(s):  
Luteinizing Hormone ◽  
Peak Level ◽  
Systemic Circulation ◽  
Bubalus Bubalis ◽  
High Concentration ◽  
Plasma Progesterone ◽  
Blood Samples ◽  
Androgen Level ◽  
The Mean ◽  
Low Levels

Abstract. Domestic buffaloes were used to characterize the pattern of progesterone, oestradiol-17β, LH and androgen in the systemic circulation following infertile insemination. Concentrations of hormones were measured by RIA in blood samples collected daily or at alternate days following insemination. The concentration of progesterone was lowest on the day of insemination, and increased significantly to a peak level of 4.00 ± 0.60 ng/ml by day 13 post insemination. After day 17, it declined significantly (P < 0.01) to reach low levels by day 21. The concentration of oestradiol-17β was high at the time of insemination and declined significantly (P < 0.01) by day 2 after insemination. It was maintained around the basal level till day 18 with minor peaks in between this period. It again rose significantly (P < 0.01) at subsequent oestrus. The mean level of LH was highest at the time of insemination, and declined significantly (P < 0.01) by day 1 post insemination. It did not vary appreciably till the animal returned to oestrus. The oestrous value of LH and progesterone were negatively correlated (r = −0.77). The androgen level was observed to be high at insemination in 3 out of 5 animals, but the overall pattern of this steroid was inconsistent during the period studied. A high concentration of androgen was recorded in all the animals from day 2–5 before the onset of oestrus.

RESTORATION OF OESTROGEN POSITIVE FEEDBACK EFFECT ON LH RELEASE BY BROMOCRIPTINE IN HYPERPROLACTINAEMIC PATIENTS WITH GALACTORRHOEA-AMENORRHOEA

1979 ◽  
Vol 91 (3) ◽  
pp. 591-600 ◽  
Author(s):  
Toshihiro Aono ◽  
Akira Miyake ◽  
Takenori Shioji Motoi Yasuda ◽  
Koji Koike ◽  
Keiichi Kurachi
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Serum Prolactin ◽  
Serum Luteinizing Hormone ◽  
Serum Lh ◽  
Lh Release ◽  
The Mean ◽  
Lh Rh ◽  
Lh Releasing Hormone ◽  
Positive Feedback Effect

ABSTRACT Five mg of bromocriptine was administered for 3 weeks to 8 hyperprolactinaemic women with galactorrhoea-amernorrhoea, in whom the response of serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to 100 μg of iv LH-releasing hormone (LH-RH) had been evaluated. Twenty mg of conjugated oestrogen (Premarin®) was injected iv any day between the 10th and 12th day from the initiation of the treatment, and serum LH levels were serially determined for 120 h. Hyperresponse of LH with normal FSH response to LH-RH was observed in most patients. Bromocriptine treatment for 10 to 12 days significantly suppressed mean (± se) serum prolactin (PRL) levels from 65.1 ± 23.0 to 10.4 ± 2.0 ng/ml, while LH (12.6 ± 2.1 to 24.8 ± 5.9 mIU/ml) and oestradiol (40.1 ± 7.6 to 111.4 ± 20.8 pg/ml) levels increased significantly. Patients on bromocriptine treatment showed LH release with a peak at 48 h after the injection of Premarin. The mean per cent increases in LH were significantly higher than those in untreated patients with galactorrhoea-amenorrhoea between 32 and 96 h after the injection. The present results seem to suggest that the restoration of LH-releasing response to oestrogen following suppression of PRL by bromocriptine may play an important role in induction of ovulation in hyperprolactinaemic patients with galactorrhoea-amenorrhoea.

EFFECTS OF CONTINUOUS DAILY ADMINISTRATION OF 0.5 mg OF CHLORMADINONE ACETATE ON THE PLASMA LEVELS OF PROGESTERONE AND ON THE URINARY EXCRETION OF LUTEINIZING HORMONE AND TOTAL OESTROGENS

1970 ◽  
Vol 63 (4) ◽  
pp. 705-716 ◽  
Author(s):  
U. Larsson-Cohn ◽  
E. D. B. Johansson ◽  
L. Wide ◽  
C. Gemzell
Keyword(s):  
Luteinizing Hormone ◽  
Plasma Level ◽  
Urinary Excretion ◽  
Corpus Luteum ◽  
Plasma Levels ◽  
Chlormadinone Acetate ◽  
The Mean ◽  
Low Levels ◽  
The Difference ◽  
All Treatment

ABSTRACT Daily determinations of the plasma level of progesterone and the urinary excretion of luteinizing hormone (LH) and total oestrogens were performed in 6 subjects during one control cycle, immediately followed by three cycles of daily treatment with 0.5 mg of chlormadinone acetate continuously. The control cycles were ovulatory according to the parameters investigated. Two of the women showed a normal LH excretion pattern in all treatment cycles. The four other subjects also had periodical variations in the LH excretion but no distinct midcycle peaks occurred. The mean oestrogen excretion was increased in all three treatment cycles but the difference was satistically significant only in the last two cycles. Compared with the treatment cycles, the sum of progesterone values was significantly decreased in the first two cycles. Chlormadinone acetate in this dose had no thermogenic effect. Three of the subjects showed bleeding irregularities which had no clear connection with the hormone variations measured in the study. It is suggested that the low levels of progesterone might be due to a defective corpus luteum function.

The effect of wilting of herbage on silage composition and its feeding value for milk production

1981 ◽  
Vol 32 (2) ◽  
pp. 171-178 ◽  
Author(s):  
F. J. Gordon
Keyword(s):  
Body Condition ◽  
Dry Matter ◽  
Post Partum ◽  
Live Weight ◽  
Milk Composition ◽  
Dry Matter Intake ◽  
Significant Depression ◽  
Feeding Value ◽  
The Mean ◽  
Block Experiment

ABSTRACTA randomized block experiment was used to assess the effects of wilting of herbage prior to ensiling. Three silages, each a composite of three harvests taken over the season, were prepared by ensiling herbage as unwilted, medium-wilted or high-wilted material with mean dry-matter contents in the resulting silages of 192, 254 and 455g/kg respectively. The silages were ensiled in bunker silos using the same harvesting machinery and with formic acid applied at the rate of 2 81/t of herbage. The silages were offered to 81 January- and February-calving cows from the 8th day post partum until going to pasture on 27 April, with a mean period on treatmen t of 92 days. In addition, all animals received a fixed concentrate allowance of 7·6 kg/day. Wilting increased silage dry-matter intake, the mean intakes being 9·2, 9·4 and 10·0kg/day for the unwilted, medium-wilted and high-wilted material respectively, but resulted in a significant depression in milk yield, with the yields obtained during the final 14 days on treatment being 23·6, 21 -8 and 21·5kg/day respectively. Milk composition, live weight, body condition, total ration digestibility and nitrogen-balance data are also presented.

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