The ovulation rate, plasma progesterone and estradiol concentration, and  litter size of a local ewe breed kept in a barn vs. those kept under an  overhead shelter

Abstract. A herd of sheep (40 heads) was divided into two equal groups: group 1 was kept under an overhead shelter and group 2 in a warm barn. The effect of maintenance on ewe's reproductive performance, corpora lutea and corpora lutea of pregnancy rate, as well as the concentration of plasma progesterone and estradiol in peripheral blood was investigated. At the first laparoscopy fewer corpora lutea than during the following one were observed (P ≤ 0.01). In sheep kept under the overhead shelter, a greater number of corpora lutea were noted. More corpora lutea of pregnancy were observed in group 1 than in the group from the barn. On the first day after mating the average level of progesterone was 190 pg mL−1, and after 2 weeks it increased to more than 300 pg mL−1 (P ≤ 0.01). The positive correlation between the number of corpora lutea of pregnancy and progesterone concentration (P ≤ 0.01) and the negative correlation (P ≤ 0.01) with number of corpora lutea of pregnancy, as well as between the litter size and estradiol concentration, were observed. Harsh environmental conditions did not cause a significant decrease of the reproduction performance of ewes kept under the overhead shed.

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Effect of deslorelin on the induction of estrus in anestrous bitches

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352010000300017 ◽

2010 ◽

Vol 62 (3) ◽

pp. 615-621 ◽

Cited By ~ 2

Author(s):

L.L. Lanna ◽

A.P. Marques Jr. ◽

R.H. Douglas

Keyword(s):

Clinical Signs ◽

Control Group ◽

Progesterone Concentration ◽

Plasma Progesterone ◽

Clinical Evaluations ◽

Injectable Formulation ◽

Vaginal Cytology ◽

Group 2 ◽

And Control ◽

Group 1

The efficacy of one or multiple doses of an injectable formulation of deslorelin (a GnRH agonist) was evaluated to induce estrus in anestrous bitches. Thirteen animals composed three groups: group 1 (n=5, single IM injection of 2mg deslorelin), group 2 (n=5, four IM injections of 2mg deslorelin in alternate days), and control group (n=3, four IM saline injections in alternate days). Daily clinical evaluations, sexual behavior, vaginal cytology, plasma progesterone concentration, ovaryhysterectomy and macroscopic evaluation of the uterus and ovaries were done. In group 1, none of the bitches showed signs of estrus, while two developed clinical signs and vaginal cytology of proestrus. In group 2, all animals presented proestrus, four presented estrus, and three ovulated; resulting in a functional corpus luteum and high progesterone concentration until day 25 of diestrus, when ovaryhysterectomy was performed. The duration of the stages of deslorelin induced cycles and the progesterone profile were similar to those described in the literature, and no side effects were observed. In conclusion, injectable formulation of deslorelin in multiple injections was effective to induce fertile estrus in anestrous bitches.

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REPRODUCTIVE PERFORMANCE IN EWES ON A LOW-SELENIUM DIET

Canadian Journal of Animal Science ◽

10.4141/cjas75-064 ◽

1975 ◽

Vol 55 (4) ◽

pp. 513-517 ◽

Cited By ~ 2

Author(s):

D. MITCHELL ◽

M. HIDIROGLOU ◽

K. J. JENKINS

Keyword(s):

Adverse Effect ◽

Sex Ratio ◽

Reproductive Performance ◽

Embryonic Mortality ◽

Group Differences ◽

Corpora Lutea ◽

Conception Rates ◽

Group 2 ◽

Low Selenium ◽

Group 1

Sixty-four Selenium (Se)-deficient ewes (group 1) and 65 Se-adequate ewes (group 2) were exposed to fertile, harnessed rams for a 42-day period (1 October–12 November 1973). Between 26 October and 7 December, approximately half of the animals in each group were slaughtered 25–30 days after their last marked mating to determine numbers of embryos and corpora lutea (CL). The percentages of ewes pregnant and CL not represented by normal embryos were 80.6 and 12.8 in group 1 and 78.8 and 34.1 in group 2 and the average number of CL/ewe was 1.57 and 1.63, respectively. The remaining ewes were kept until anticipated time of lambing. The percentage of ewes which lambed and the average number of lambs/ewe were 67.9 and 1.47 (group 1) and 71.9 and 1.44 (group 2). No group differences in sex ratio of lambs was observed. Composite conception rates for the slaughtered and lambed ewes were 76.2% for the Se-deficient and 76.6% for the Se-adequate animals. It was concluded that under the conditions of this experiment Se depletion had no adverse effect on ewe conception rates, embryonic mortality or numbers of lambs born.

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Reduced LH sensitivity in vivo and in vitro of corpora lutea induced during anoestrus by GnRH, and during the late breeding season, in Scottish Blackface ewes

Journal of Endocrinology ◽

10.1677/joe.1.05918 ◽

2004 ◽

Vol 183 (3) ◽

pp. 517-526 ◽

Cited By ~ 2

Author(s):

T A Bramley ◽

D Stirling ◽

G S Menzies ◽

D T Baird

Keyword(s):

Breeding Season ◽

High Plasma ◽

Corpora Lutea ◽

Plasma Progesterone ◽

Group 4 ◽

Group 3 ◽

Group 2 ◽

Group 1

Scottish Blackface ewes were synchronised in mid-breeding (November; group 1; n=12 ewes) or late-breeding season (March; group 2; n=16). Anoestrous ewes (May) were treated with progestagen sponges for 7 days and then given 250 ng GnRH 3-hourly for 24 h, 2-hourly for 24 h and hourly for a further 24 h (group 3; n=12). A second group of anoestrous ewes (group 4, n=19) received three bolus injections (30 μg) of GnRH at 90-min intervals without progestagen pretreatment. After ovulation, ewes were bled twice daily until slaughter (day 4 or day 12: oestrus=day 0). Mid-breeding season (group 1) and anoestrous ewes in group 3 formed ‘adequate’ corpora lutea (CL) with high plasma progesterone levels (3–4 ng/ml) maintained for at least 12 days, and responded in vivo to ovine LH (oLH) (10 μg) with a rise in plasma progesterone on day 11 (group 3, but not group 1, ewes also responded on day 3). CL minces from these ewes responded to human chorionic gonadotrophin (hCG) in vitro with a dose-dependent increase in progesterone secretion. Ewes in group 4 had a foreshortened luteal phase (8–10 days) and low plasma progesterone levels (~1 ng/ml), consistent with formation of inadequate CL. LH injection failed to induce a significant plasma progesterone increase. Furthermore, although progesterone secretion in vitro in response to maximally stimulating doses of hCG or dibutyryl cAMP (dbcAMP) was similar to that in adequate CL, the sensitivity of these CL to hCG (EC (effective concentration)50, 1 IU hCG/ml) was reduced 10-fold compared with adequate CL (EC50, 0.1 IU hCG/ml; P<0.01). Ewes that ovulated in the late breeding season (group 2) had high plasma progesterone, although levels began to decrease after day 10. Injection of oLH in vivo increased plasma progesterone. However, sensitivity to hCG in vitro (EC50, 0.5 IU hCG/ml) was intermediate between that of adequate luteal tissue (groups 1 and 3; EC50, 0.1 IU/ml) and that of group 4 ewes (EC50, 1 IU hCG/ml). Our data demonstrate a markedly reduced luteal sensitivity to LH in vivo and hCG in vitro in Scottish Blackface ewes with inadequate CL, and suggest that a similar loss of sensitivity to LH may occur in the late breeding season.

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Ultrasonography and hormone profiles of persistent ovarian follicles (cysts) induced with low doses of progesterone in cattle

Reproduction ◽

10.1530/reprod/120.2.361 ◽

2000 ◽

pp. 361-366 ◽

Cited By ~ 11

Author(s):

KM Noble ◽

JE Tebble ◽

D Harvey ◽

H Dobson

Keyword(s):

Ovarian Follicles ◽

Oestrous Cycle ◽

Blood Collection ◽

Progesterone Concentration ◽

Plasma Progesterone ◽

Follicular Wave ◽

Low Concentrations ◽

Group 2 ◽

Intravaginal Device ◽

Group 1

The aims of this study were to expose dominant ovarian follicles at the end of the oestrous cycle to low progesterone concentrations similar to those that occur during stress, and to examine the effect of a subsequent small increase in progesterone 10 days later. Half a progesterone releasing intravaginal device (0.5 PRID) was administered to 13 heifers from day 15 of the oestrous cycle. In group 1 (n = 7), one 0.5 PRID remained in place until day 40 or until each heifer ovulated. In group 2 (n = 6), the first 0.5 PRID was removed on day 28, and replaced immediately with a second 0.5 PRID. Ultra-sonography and blood collection (10 ml) were conducted each day for 26 days from day 14 and then on alternate days. The largest follicle that emerged during the first 5 days after insertion of the initial 0.5 PRID remained > 10 mm in diameter for 15.3 +/- 1.7 and 11.6 +/- 0.4 days in groups 1 and 2, respectively. This period of dominance, during which no other follicles emerged, was closely correlated with the duration of plasma oestradiol concentrations exceeding 10 pg ml(-1). In four heifers from group 1, the persistent follicle ovulated between days 30 and 37 (sub-group 1a; 0.5 PRID expelled). In three heifers from sub-group 1b (0.5 PRID retained), the dominant follicle secreted oestradiol for 17 +/- 5 days but remained detectable by ultrasonography for a total of 33 +/- 8 days (range 26-52 days). Monitoring continued beyond day 40 in these animals. In group 2, the new 0.5 PRID inserted on day 28 resulted in an increase in plasma progesterone concentration of 0.9 +/- 0.3 ng ml(-1). Simultaneously, oestradiol decreased by 10.1 +/- 3.3 pg ml(-1), and a new follicular wave emerged 5-7 days later. In conclusion, exposure to very low concentrations of progesterone produced persistent follicles that secreted oestradiol for 17 days. This oestradiol production could be disrupted by a second increase of 0.9 ng ml(-1) in peripheral progesterone concentration. In the absence of the second progesterone treatment, some of the persistent follicles remained detectable by ultrasonography for up to 52 days, despite cessation of oestradiol secretion.

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173TRANSFER OF VITRIFIED BLASTOCYSTS FROM ONE OR TWO SUPEROVULATED LARGE WHITE HYPERPROLIFIC DONORS TO MEISHAN RECIPIENTS: REPRODUCTIVE PARAMETERS AT DAY 30 OF PREGNANCY

Reproduction Fertility and Development ◽

10.1071/rdv16n1ab173 ◽

2004 ◽

Vol 16 (2) ◽

pp. 208

Author(s):

C. Cuello ◽

F. Berthelot ◽

F. Martinat-Botté ◽

P. Guillouet ◽

V. Furstoss ◽

...

Keyword(s):

Pregnancy Rate ◽

Fisher Exact Test ◽

Corpora Lutea ◽

Large White ◽

Embryo Survival ◽

Exact Test ◽

Group 2 ◽

Fresh Semen ◽

Group 1

The present study was designed to determine the effect of pooling embryos from two donors on the reproductive success of transfer of vitrified/warmed porcine blastocysts. Superovulated Large White hyperprolific gilts (n=24) were used as embryo donors. Gilts were artificially inseminated 12 and 24h after initial detection of estrus using fresh semen, and slaughtered on Days 5.5 to 6 of the estrous cycle (Day 0=Onset of estrus). Embryos were recovered by flushing the uterine horns, and unhatched blastocysts were selected. Vitrification and warming were performed as reported previously (Berthelot et al., 2000 Cryobiology 41, 116–124). Embryo transfers were conducted in asynchronous (−24h) Meishan gilts (n=20). Twenty vitrified/warmed blastocysts were surgically transferred into one uterine horn. Ten recipients received embryos from one donor (group 1) and the other ten transfers were performed with mixed embryos from two donors (group 2). Pregnancy was assessed ultrasonographically at Day 25 after estrus and recipients were slaughtered five days later. The pregnancy rate from the different groups was compared using Fisher exact test. The GLM procedure of SAS was used to determine the effect of the origin of embryos (one or two donors) on the number of developed fetuses and viable fetuses at Day 30 of pregnancy. The ovulation rate was 32.5±11.8 (mean±SD). The total number of embryos collected was 634, of which 57 (9.0%), 36 (5.7%), 513 (80.9%) and 28 (4.4%), were unfertilized oocytes and degenerated embryos, morulae, unhatched blastocysts and hatched blastocysts, respectively. The ratio of collected embryos to the number of corpora lutea was 81.3%. The pregnancy rate for group 1 (70%) was not different (P>0.05) than that for group 2 (90%). No significant differences were detected between group 1 and group 2 for in vivo embryo development (number fetuses/transferred embryos in pregnant recipients; 33.3% v. 40%) or in vivo embryo survival (number viable fetuses/transferred embryos in pregnant recipients; 27.9% v. 33.9%). However, the in vivo efficiency (number viable fetuses/total transferred embryos) was higher (P<0.05) when transfers were performed with embryos from two donors (19.5% v. 30.5%). These results indicate that pooling embryos from two donors increases the in vivo efficiency after transfer of vitrified/warmed porcine blastocysts. This study was supported by grant from SENECA (FPI/99, Spain).

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Effect of different diet supplements in the pre- and post-partum period on reproductive performance in the dairy cow

BSAP Occasional Publication ◽

10.1017/s0263967x00033838 ◽

2001 ◽

Vol 26 (2) ◽

pp. 313-321 ◽

Cited By ~ 1

Author(s):

N. H. Gardner ◽

C. K. Reynolds ◽

R.H. Phipps ◽

A.K. Jones ◽

D.E. Beever

Keyword(s):

Sugar Beet ◽

Dairy Cows ◽

Reproductive Performance ◽

Post Partum ◽

Late Gestation ◽

Diet Supplements ◽

Group 2 ◽

The Impact ◽

Ration Group ◽

Group 1

AbstractThe study compared the impact of feeding different energy supplements (barley, molassed sugar beet and fat) prior to calving and the effects of feeding supplemental fat post-partum, on subsequent production and reproductive efficiency of dairy cows. Forty-eight multiparous Holstein-Friesian dairy cows were assigned to one of two groups, six weeks prior to expected calving date and fed a grass based total mixed ration according to ME requirements for late gestation. Group 1 was supplemented with barley (B) or molassed sugar beet feed (SB) prior to calving and was then given a high starch lactation ration. Group 2 was supplemented with either fat (F) or no supplement (C) pre partum, and was then given a similar lactation ration as Group 1 but supplemented with fat. Lactation rations were fed through to week-20 post partum and the cows were monitored during this period. Milk yield (P<0.002) and milkfat (P<0.02) production were higher and milk protein concentration (P<0.001) was lower in Group 2. The number of days to first rise in progesterone following parturition was greater (P<0.01) in Group 2. Due to the design of the study, effects of prepartum supplementation were only evaluated within each lactation ration group. Conception rate to first service was higher (P<0.001) for B than SB supplemented cows in Group 1 and higher (P<0.02) for F than C supplemented cows in Group 2. Services per conception were lower (P=0.06) for B than SB supplemented cows in Group 1 and lower (P<0.05) for F than C supplemented cows in Group 2. Overall pregnancy rates and days open were not significantly different between the groups. The data shows that pre-partum nutrition had an important role in determining subsequent fertility. Despite having negative effects early post partum, supplementing with fat did not affect overall reproductive performance but it did improve milk production.

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Milk yield at first lactation, parity, and season of calving affect the reproductive performance of water buffalo cows

Animal Production Science ◽

10.1071/an18420 ◽

2020 ◽

Vol 60 (8) ◽

pp. 1073

Author(s):

Héctor Nava-Trujillo ◽

Robert Valeris-Chacin ◽

Armando Quintero-Moreno ◽

Juan Escalona-Muñoz

Keyword(s):

Milk Yield ◽

Reproductive Performance ◽

Water Buffalo ◽

Negative Energy ◽

Calving Interval ◽

Water Buffaloes ◽

Group 4 ◽

Group 3 ◽

Group 2 ◽

Group 1

Context Profitability of water buffalo systems depends on a calving interval (CI) <400 days. Several factors affect the achievement of this target. However, milk yield at first lactation has received little attention. Aims Determine the effect of milk yield at first lactation, parity, season of calving and farm, on the length of CI and the probability of a CI ≤ 400 days in water buffaloes. Methods A retrospective analysis of milk yield at first lactation and reproductive records of 1459 water buffaloes was carried out. Milk yield was categorised as Group 1 (≤1090 kg), Group 2 (1090–1377 kg), Group 3 (1377–1684 kg) and Group 4 (>1684 kg); parity was categorised as parity 1, 2 and ≥ 3; and month of calving was grouped into three seasons: December–March, April–July, and August–November. Data were analysed using linear and logistic mixed models. Key results CI increased from 425.3 days (95% CI: 418.8–431.8 days) in group 1 to 463.3 days (95% CI: 456–470.6 days) in group 4 (P < 0.05), while the probability of having a CI ≤ 400 days decreased from 0.5 (95% CI: 0.46–0.54) to 0.26 (95% CI: 0.22–0.29), respectively (P < 0.05). CI decreased from 466 days (95% CI: 460.8–471.3 days) in parity 1 to 410.5 days (95% CI: 405.2–415.8 days) in parity ≥3, whereas the probability of a CI ≤ 400 days increased from 0.26 (95% CI: 0.24–0.29) to 0.51 (95% CI: 0.47–0.54) respectively (P < 0.05). Water buffaloes calving in August–November showed significantly shorter CI and, along with those calving between December–March, showed the highest probability of a CI ≤ 400 days. An interaction between milk yield at first lactation and parity on both outcomes was observed. Conclusions Shorter CI and higher probability of a CI <400 days were associated with lower milk yields at first lactation, higher parity and calving between August–November. Higher milk yield at first lactation affected negatively the reproductive performance of water buffaloes, especially at parity 1 and 2. Implications These results highlight the importance of adequate nutritional management to allow water buffaloes to cope with the challenge of the postpartum negative energy balance and have a calving interval less than 400 days.

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Effects of Dietary α-Tocopherol and Polyunsaturated Fats on the Fatty Acid Composition of Platelet Phospholipids and on Blood Coagulation

10.1055/s-0039-1689522 ◽

1975 ◽

Author(s):

K. Korsan-Bengtsen ◽

B. Hallgren ◽

A.-C Teger-Nilsson

Keyword(s):

Fatty Acid ◽

Negative Correlation ◽

Platelet Rich Plasma ◽

Alpha Tocopherol ◽

Control Group ◽

Platelet Factor ◽

Group 4 ◽

Polyunsaturated Fats ◽

Group 2 ◽

Group 1

The study group was 40 male post myocardial infarction patients 47-57 years old. All the participants were investigated two times with two weeks interval after which they were randomly divided into four groups with 10 subjects in each. Group 1 was given alpha-tocopherol 300 mg/day, group 2 was given alpha tocopherol 300 mg/day and a diet containing extra polyunsaturated fats, group 3 was given extra polyunsaturated fats but no extra alpha-tocopherol and group 4 served as a control group – thus continued their ordinary diet. After three months all participants were again investigated twice with two weeks interval.On the values from all 40 subjects before the start of the dietary regimens linear regression analyses showed that there was a significant correlation between the content of the fatty acid 18 : 0 in the serin cephalin fraction and re calcification time in platelet rich plasma (RPRP), and a negative correlation between 20: 4 and RPRP. There was also a correlation between the ratio 18: 0/20: 4 and RPRP and a negative correlation between 18: 0/20: 4 and platelet factor 3 activity in plasma.In group 2 there was a significant decrease in 18:0 and an increase in 20: 4 in the serin cephalin fraction from platelets after the diet period compared to preexperimental values. Russel’s viper venom clotting time (RVV) decreased significantly in group 1. There was a significant correlation between the decrease in RVV and the increase in plasma alphatocopherol.

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Protected fat and donor age effects on plasma total lipid level, plasma progesterone concentration, embryo yield and quality following superovulation in sheep

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200002155 ◽

1999 ◽

Vol 1999 ◽

pp. 60-60

Author(s):

AG Onal ◽

JJ Robinson ◽

ME Staines ◽

BK Speake ◽

JSM Hutchinson ◽

...

Keyword(s):

Dietary Fat ◽

Plasma Cholesterol ◽

Lipid Level ◽

Corpora Lutea ◽

Progesterone Concentration ◽

Donor Age ◽

Plasma Progesterone ◽

Beneficial Effects ◽

Yield And Quality ◽

Critical Phases

Supplements of dietary fat are highly effective in boosting energy intake at critical phases during the reproductive cycle. When fed to ruminants in the form of calcium salts of fatty acids, they have been shown to increase plasma cholesterol and progesterone levels (Spicer et al, 1993) which, in turn, could have beneficial effects on ovulation rate and embryo quality. In sheep, a likely reproductive state for a physiological response to a lipid supplement is during the superovulation of young animals in which the post-ovulatory steroidogenic capacity of the corpora lutea may be sub-optimal. The present study examined the effects of donor age and dietary fat on plasma progesterone concentration, and the yield and quality of embryos in superovulated Cheviot sheep.

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