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.

The effect of pre- and post-partum energy and protein supply on the performance of single- and twin-suckling beef cows and their calves

1994 ◽  
Vol 59 (3) ◽  
pp. 379-389 ◽  
Author(s):  
K. D. Sinclair ◽  
P. J. Broadbent ◽  
J. S. M. Hutchinson
Keyword(s):  
Energy Intake ◽  
Body Condition ◽  
Dry Matter ◽  
Body Condition Score ◽  
Post Partum ◽  
Live Weight ◽  
Trial Period ◽  
Condition Score ◽  
Daily Milk ◽  
Body Condition Scores

AbstractChanges in live weight, body condition, milk production and composition were monitored for single- and twinsuckling cows in two experiments. In experiment 1, all cows were managed for 3 months before calving to achieve condition scores at calving 2·1 (low) and 3·1 (moderate). Subsequently, these animals were placed on a fixed level of energy intake (80 MJ metabolizable energy (ME) per day) for 16 weeks. Post-partum diets contained differing amounts of digestible undegradable protein (DUP), but similar amounts of effective rumen degradable protein (ERDP). In experiment 2, single- and twin-suckling cows were fed to achieve a condition score at calving of around 2·75. These animals were subsequently placed on two levels of energy intake (80 MJ and 130 MJ ME per day) during the first 16 weeks of lactation. The diets providing these energy intakes also contained differing amounts of DUP. Neither the level of DUP in the diet nor the level of feeding significantly altered the digestibility of the dry matter or organic matter in the dry matter of the experimental diets.Body condition at calving had little effect on daily milk yield (9·5 kg) and composition (33·5 g/kg fat; 30-0 g/kg protein) in experiment 1. Cows with higher body condition scores at calving lost 13·5 kg more live weight and 0·26 units more body condition (P < 0·05) during the 1st month post partum but remained in better condition throughout the trial period than cows with lower body condition scores. Cows on 130 MJ ME per day produced higher (P < 0·001) daily yields of milk, milk fat and protein (+2·0 kg; +151 g; +85 g) and lost 57 kg less live weight and 0·52 units less body condition (P < 0·001) than cows on 80 MJ ME per day. Elevated dietary levels of DUP promoted (P < 0·05) daily milk yields (by 1·25 kg) and reduced live-weight and body condition-score loss during the 1st month post partum in both experiments. Twin-suckling cows produced the highest average daily yields of milk throughout the 16-week trial period in both experiments but yields were not significantly higher after early lactation in experiment 1. Cow body condition score at calving and the level of DUP in the post-partum diet of cows had no effect on the post-partum performance of calves. Twin calves had slower growth rates (P < 0·001) than single calves (0·65 and 1·07 kg/day respectively) in experiment 1. However, twin calves sucking cows on 130 MJ ME per day in experiment 2 grew similarly to single sucking calves from week 8 of lactation (0·8 kg/day).

Resumption of oestrous and ovarian cyclicity during the post-partum period in autumn-lambing ewes is not influenced by age or dietary protein content

1998 ◽  
Vol 67 (1) ◽  
pp. 65-72 ◽  
Author(s):  
L. M. Mitchell ◽  
M. E. King ◽  
F. E. Gebbie ◽  
M. J. Ranilla ◽  
J. J. Robinson
Keyword(s):  
Protein Content ◽  
Body Condition ◽  
Dietary Protein ◽  
Post Partum ◽  
Live Weight ◽  
Post Partum Period ◽  
Ovarian Cyclicity ◽  
Effect Of Age ◽  
Ovarian Cycles ◽  
Body Condition Scores

AbstractThe objective was to determine the effect of age and dietary protein content on post-partum oestrous and ovarian cyclicity in autumn-lambing ewes. Twenty-four multiparous (age 4·5 (s.e. 0·61) years) and 24 primiparous (age 1·5 years) ewes which lambed on 28 October (s.e. 0·2) and were rearing 2·0 and. 1·7 (s.e. 0·13) lambs, respectively, were equally allocated to two dietary treatments in a 2 × 2 factorial design. Diets comprised a d libitum hay supplemented with concentrate (12·5 MJ metabolizable energy per kg dry matter (DM) and either 210 or 140 g crude protein per kg DM), offered at a daily allowance of 1·2 kg per ewe from lambing to weaning (18 December) and 0·4 kg per ewe thereafter. Throughout the study (3 November to 24 May) ewes were group-housed in straw-bedded pens under natural photoperiod at 57°N and their live weights and body condition scores were assessed at 2-week intervals. A raddled vasectomized ram was continually present with each group and ewes marked by the ram were recorded thrice weekly. Blood samples were obtained thrice weekly for measurement of peripheral progesterone concentrations and ovulation rate was determined by laparoscopy during January and March. There was no significant effect of dietary protein content on any of the variables measured. For multiparous and primiparous ewes, mean live weights and body condition scores at lambing were 79·5 (s.e. 1·41) v. 58·4 (s.e. 1·54) kg (P < 0·001) and 2·5 (s.e. 0·05) v. 2·2 (s.e. 0·05) (P < 0·001) and daily live-weight losses over the suckling period were 153 (s.e. 19·3) v. 85 (s.e. 21·1) glday (P < 0·05). Intervals from parturition to first overt oestrus were 39 (s.e. 3·2) v. 33 (s.e. 2·3) days and to the onset of ovarian cyclicity were 29 (s.e. 4·9) v. 25 (s.e. 1·5) days. Durations of ovarian cyclicity were 133 (s.e. 27·1) and 110 (s.e. 5·7) days (P < 0·01) during which 7·6 (s.e. 0·32) and 6·5 (s.e. 0·34) (P < 0·05) ovarian cycles were recorded respectively. Fifteen ewes had initial short cycles (≤10 days), six had prolonged cycles (≥21 days) and 11 had extended inter-luteal phase intervals (≥8 days). All ewes had recent ovulations at the January laparoscopy but only 19 multiparous and nine primiparous ewes had ovulations in March. Mean ovulation rates were: January 2·2 (s.e. 0·14) and 1·4 (s.e. 0·13) (P < 0·001), and March 1·6 (s.e. 0·23) and 1·2 (s.e. 0·15) for multiparous and primiparous ewes, respectively. It is concluded that, for ewes lambing at their normal time of mating, (i) the strong seasonal drive for reproduction results in the resumption of oestrous and ovarian cyclicity during the early post-partum period; (ii) initial luteal phases may be of short or extended duration; (Hi) there is no effect of age or dietary protein content, within the range studied, on the onset of ovarian cyclicity; and (iv) multiparous ewes experience a greater number of ovarian cycles and achieve higher ovulation rates than primiparous ewes.

scholarly journals Effect of bovine somatotropin (growth hormone) treatment on gonadotropin profiles and ovarian follicle populations during the postpartum period in beef cows in low body condition

1993 ◽  
Vol 1993 ◽  
pp. 89-89
Author(s):  
L.P. Andrade ◽  
S.M. Rhind ◽  
I.A. Wright ◽  
S.R. McMillen ◽  
T.K. Whyte
Keyword(s):  
Growth Hormone ◽  
Body Condition ◽  
Growth Hormone Treatment ◽  
Ovarian Function ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Hormone Treatment ◽  
Beef Cows ◽  
Follicle Development ◽  
Ovarian Follicle Development

Cows in low body condition exhibit a prolonged postpartum anoestrous period and a delayed return to normal follicular function (Prado et al 1990). Previous studies have shown that the effects of body condition on gonadotrophin profiles are inconsistent (Wright et al 1990; Rhind et al 1992) indicating that the effects of body condition on ovarian function cannot be explained by changes in gonadotrophin profiles alone. Since nutritional state influences growth hormone profiles which in turn can affect ovarian function (Gong et al 1991), it was postulated that the effects of body condition on the duration of postpartum anoestrus could be mediated through changes in profiles of this hormone.The aim of the present study was to determine the effect of growth hormone on ovarian follicle development and associated gonadotrophin profiles in post-partum beef cows.

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.

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).

Circulating concentrations of LH and FSH and pituitary responsiveness to GnRH in intact and ovariectomized suckled beef cows in two levels of body condition

1990 ◽  
Vol 51 (1) ◽  
pp. 93-101 ◽  
Author(s):  
I. A. Wright ◽  
S. M. Rhind ◽  
T. K. Whyte ◽  
A. J. Smith ◽  
S. R. McMillen ◽  
...  
Keyword(s):  
Body Condition ◽  
Body Condition Score ◽  
Post Partum ◽  
Live Weight ◽  
High Sensitivity ◽  
Fold Increase ◽  
Beef Cows ◽  
Pulse Frequency ◽  
Condition Score ◽  
Physiological Dose

ABSTRACTThe effect of body condition on hypothalamic and pituitary function in post-partum suckled beef cows was studied. Thirty-eight Blue-Grey cows were calved at a body condition score of either 2·35 (L) or 2·80 (H), fed to maintain live weight and body condition thereafter and ovariectomized at either 5 or 9 weeks post partum. The H cows had higher LH pulse frequencies before ovariectomy (0·36 v. 0·28 pulses per h; P < 0·05) and 15 days after ovariectomy (0·86 v. 0·72 pulses per h; P < 0·01), indicating a direct effect of body condition on GnRH release from the hypothalamus. Body condition had no effect on the ability of the pituitary to release LH in response to a physiological dose (2·5 u.g) of GnRH in entire or ovariectomized cows at 5 or 9 weeks post partum. The magnitude of the increase in circulating levels of LH following GnRH injection was greater at 9 weeks compared with 5 weeks post partum (2·23 v. 1·73 u.g/1; P < 0·001) in entire cows, but there was no difference between 5 and 9 weeks in ovariectomized cows. Following ovariectomy there was a 2·5-fold increase in LH pulse frequency within 15 days and LH pulse frequency approached 1 pulse per h in all treatments groups. It is concluded that both the hypothalamus and the pituitary are capable of functioning normally by 5 weeks post partum in suckled beef cows, that the pulsatile release of GnRH from the hypothalamus is inhibited, possibly due to a very high sensitivity to oestradiol, and that the sensitivity of the pituitary to the negative feedback effect of oestradiol may decrease with time post partum.

The effect of ewe body condition at lambing on the performance of ewes and their lambs at pasture

1980 ◽  
Vol 95 (3) ◽  
pp. 631-640 ◽  
Author(s):  
M. J. Gibb ◽  
T. T. Treache
Keyword(s):  
Body Condition ◽  
Growth Rates ◽  
Stocking Density ◽  
Live Weight ◽  
The Body ◽  
Daily Growth ◽  
Stocking Rates ◽  
Lamb Growth ◽  
Secretion Rates ◽  
Body Condition Scores

SUMMARYEwes in body condition scores of 2·4 (thin) or 3·2 (fat) on a 5-point scale and suckling twin lambs were grazed at two stocking rates for the first 16 weeks of lactation. Paddocks were grazed for periods of 2 weeks at densities of 80 and 160 ewes/ha in weeks 1–8 and then 70 and 140 ewes/ha in weeks 9/16 of lactation.Intakes of herbage by ewes were not significantly affected by body condition. Estimation of milk yield by weekly measurement of secretion rates over 4 h failed to demonstrate significant differences due to body condition except in weeks 9, 11 and 12, although there was a tendency throughout for fat ewes to produce more milk. However, the daily growth rates of the lambs during the first 8 weeks and the overall live-weight gains were significantly higher for lambs suckled by fat ewes than for those suckled by thin ewes. Intake of herbage by lambs was not affected by the body condition of the ewes.Herbage intakes, milk yields and lamb growth rates were all significantly higher at the low stocking density than at the high stocking density.

scholarly journals Evaluation of offspring of dairy sheep given water supplemented with crude glycerin during pregnancy and lactation

2016 ◽  
Vol 37 (4Supl1) ◽  
pp. 2567
Author(s):  
Hemilly Cristina Menezes Sá ◽  
Iran Borges ◽  
Gilberto De Lima Macedo Junior ◽  
Felipe Santiago Santos ◽  
Luigi Francis Lima Cavalcanti ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Condition ◽  
Body Condition Score ◽  
Live Weight ◽  
The Body ◽  
Crude Glycerin ◽  
Body Measurements ◽  
Condition Score ◽  
Pregnancy And Lactation ◽  
Body Condition Scores

The objective of this study was to evaluate the effects of crude glycerin (CG) supplementation of dairy ewes during pregnancy and early lactation on the body weight and measurements of offspring from birth to weaning. Twenty-four lambs from 24 Lacaune x East Friesian genotype ewes were evaluated. The sheep were distributed in four treatments that differed in crude glycerin supplementation of 0%, 1.5%, 3.0%, and 4.5%, as well as the concomitant adjustment of dry matter and water intake. Body measurements of lambs were recorded every two weeks from birth until weaning. Body weight was recorded daily. Multiple regression analysis revealed that supplementation with CG explained 5.2% of the variation in the weight of lambs at birth (LW), accompanied by the body condition score of the ewe (12.3%), sex of lamb (19.2%), and live weight of the ewes (26.5%); r2 was 63%. According to the predictions of the model adjusted for simulated scenarios, the leanest lambs were derived from ewes weighing between 40 and 50 kg, with body condition scores from 4 to 5, and that did not receive CG at intermediate levels. Heavier lambs, with LW above 5.5 kg, were derived from ewes that weighed between 80 to 90 kg with low body condition scores of 3, and that received 1.5% CG. Supplementation with CG between 2% and 4% improves the weight of the lambs at birth. Body measurements of lambs were not influenced by dietary supplementation of ewes with CG.

Ovarian follicular populations, steroidogenic capacity and physiological status in post-partum suckling beef cows in high and low body condition

1989 ◽  
Vol 1989 ◽  
pp. 149-149
Author(s):  
R. Prado ◽  
S.M. Rhind ◽  
I.A. Wright ◽  
A.J.F. Russel ◽  
S.M. McMillen ◽  
...  
Keyword(s):  
Body Condition ◽  
Body Condition Score ◽  
Post Partum ◽  
Weight Maintenance ◽  
Live Weight ◽  
Beef Cows ◽  
Pulse Frequency ◽  
Physiological Status ◽  
Condition Score ◽  
Maintenance Ration

Recent evidence indicates that body condition at calving has an important effect on the length of the post-partum anoestrous period in beef cows being longer in cows calving in low body condition (Richards et al, 1986, Wright et al, 1987). It is known that body condition affects baseline concentrations of LH (Rutter and Randel, 1984) and LH pulse frequency (Wright et al, 1987). However, the effect of body condition on ovarian follicles has not been studied.An experiment was designed to examine the effect of body condition score (BCS) at calving on follicle populations, follicular steroidogenic capacity, follicular histology and patterns of gonadotropin release at two different stages of the post-partum period (5 and 9 weeks after calving) in suckling beef cows.Thirty-eight suckling Blue-Grey cows with a mean live-weight of 567 ± 9.4 kg and mean BCS of 3.0 ± 0.05 at 110 days before calving to a synchronized insemination were differentially fed so that they achieved BCS of 2.83 ± 0.05 and 2.30 ± 0.05 for cows on a high (H) and low (L) plane of nutrition, respectively. After calving cows were fed a live-weight maintenance ration according to individual requirements. Cows of each BCS were ovariectomized at either 5 (w5) or 9 (w9) weeks after calving and follicles > 3mm in diameter were dissected from the ovaries and incubated for 2 h in culture medium (Medium 199) at 37°C. Follicles were then kept in Bouin's solution until histological examination. Follicle incubates were assayed for progesterone, testosterone and oestradiol. Blood samples were taken 2 days before ovariectomy for 10 h every 15 minutes and were later assayed for LH (all the samples) and FSH (every third sample).

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