The effect of melatonin treatment in combination with progestagen pessaries on reproductive performance of ewes during the anoestrous period

1997 ◽  
Vol 65 (1) ◽  
pp. 71-74 ◽  
Author(s):  
V. Laliotis ◽  
A. Vosniakou ◽  
A. Lymberopoulos ◽  
J. M. Doney ◽  
S. Kouimtzis
Keyword(s):  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Conventional Treatment ◽  
Ultrasound Scanning ◽  
Melatonin Treatment ◽  
Breeding Date ◽  
Commercial Flock ◽  
The Mean ◽  
The Difference ◽  
Pregnant Ewe

AbstractThe objective of this study was to compare the effects of melatonin implants combined with intravaginal, progestagen-impregnated pessaries with the conventional treatment of progestagen pessaries followed by pregnant mare serum gonadatrophin (PMSG) on the reproductive performance of ewes during the anoestrous period.A commercial flock of 179 seasonally anoestrous Chios crossbred ewes was used. The ewes within the flock were randomly allocated to one of two groups. Ewes of group MP (melatonin + pessaries) received melatonin implants on 20 March (50 days before the target breeding date of 10 May) and were treated with intravaginal progestagen pessaries 35 days later (25 April). Ewes of group PP (pessaries + PMSG) were also treated with pessaries on 25 April. After 14 days the pessaries were removed from both groups and 500 i.u. PMSG was injected (i.m.) into ewes of group PP only. Fertile rams were introduced into both groups 24 h after sponge removal. Pregnancy rate and litter size were determined by ultrasound scanning 80 days after ram introduction.Pregnancy rate at first oestrus was significantly higher in group MP than in group PP (57 v. 40%, P < 0·05). The overall conception rate during two oestrous cycles was significantly higher in group MP than in group PP (78 v. 59%, P < 0·02). The groups did not differ significantly in the mean number of foetuses per pregnant ewe that conceived during the first or second oestrus after pessary removal (1·78 and 1·87, respectively). The total number of foetuses per treated ewe was higher in group MP than in group PP (1·39 v. 1·10) as a consequence of the difference in pregnancy rate.

The effect of feed restriction on sexual maturity and initial reproductive performance of broiler pullets under different light treatments

1969 ◽  
Vol 9 (39) ◽  
pp. 417 ◽  
Author(s):  
RAE Pym ◽  
R Sledge
Keyword(s):  
Body Weight ◽  
Reproductive Performance ◽  
Sexual Maturity ◽  
Feed Restriction ◽  
Restricted Feeding ◽  
Egg Weight ◽  
Laying Performance ◽  
The Mean ◽  
The Difference ◽  
Lighting Systems

An experiment was conducted to examine the effect of restricted feeding under two lighting systems during the rearing period on the initial laying performance of broiler type pullets. The rearing treatments were imposed at nine weeks of age, removed at 22 weeks and the trial was discontinued at 36 weeks of age. The feeding treatments (restricted versus ad lib.) were arranged factorially with the lighting treatments (decreasing versus increasing). Birds reared on restricted feeding reached sexual maturity 16 days later than full fed birds, ate 17 per cent less feed to 22 weeks and gained seven per cent less in body weight to 24 weeks of age and ten per cent less to 36 weeks. Birds reared under the decreasing lighting regime reached sexual maturity at the same age as those reared under increasing lighting, ate five per cent more feed during the rearing and laying periods and gained five per cent more in body weight to 24 weeks. The mean weight of eggs laid between 24 and 34 weeks of age from pullets subjected concurrently to decreasing lighting and restricted feeding was approximately two grams heavier than that of the other three treatment combinations. Mean egg weight was one gram greater in the restricted than in the full fed group, although the difference was not statistically significant. Laying mortality was lower in the restricted fed group than in the full fed group.

scholarly journals RELATIONSHIP OF ELECTRICAL RESISTANCE OF VAGINAL MUCUS DURING OESTRUS WITH POST-AI PREGNANCY IN COWS

2018 ◽  
Vol 15 (2) ◽  
pp. 113-117 ◽  
Author(s):  
M. Ahmed ◽  
M. K. Chowdhury ◽  
M. M. Rahman ◽  
J. Bhattacharjee ◽  
M. M. U. Bhuiyan
Keyword(s):  
Pregnancy Rate ◽  
Electrical Resistance ◽  
Genital Tract ◽  
Conception Rate ◽  
Heat Detector ◽  
The Mean ◽  
The Difference ◽  
Rectal Palpation ◽  
Relationship Of ◽  
In Pregnancy

Accurate detection of oestrus is a common problem for farmers to do AI timely resulting in conception failure in cows. The objective of the present study was to know the electrical resistance of vaginal mucus (ERVM) during oestrus to determine the best time of AI for improvement of conception in cattle. A total of 28 cows were inseminated with frozen thawed semen after detection of ERVM with Draminski estrus detector at Kendua Upazila Livestock Office under Netrakona district of Bangladesh. Pregnancy was diagnosed by per rectal palpation of genital tract 8-10 weeks after insemination. The mean ERVM in pregnant cows was 208.5 ± 31.2 Ω (163.3 to 263.3 Ω) and the ERVM in non-pregnant cows was 214.4 ± 36.6 Ω (153.3 to 280.0 Ω). Moreover, the pregnancy rate was higher in cows (80.0 to 83.3%) when ERVM during oestrus varied from 150 to 220 Ω than that of 221 to 280 Ω counterpart (36.4%). The difference in pregnancy rates between groups was significant (P<0.05). The present study indicates that Dramniski electrical heat detector may be used for prediction of time for AI in cows of Bangladesh. Up to 220 Ω ERVM during oestrus is better for higher conception rate than that of more than 220 Ω counterparts. Further studies with high number of inseminated cows should be conducted before wide application of this electrical heat detector under field conditions in Bangladesh.

The effect of immunoneutralization of PMSG near a gonadotropin-induced oestrus on the reproductive performance of gilts

1994 ◽  
Vol 58 (3) ◽  
pp. 401-404 ◽  
Author(s):  
R. N. Kirkwood ◽  
A. J. Peacock ◽  
T. A. Van Lunen ◽  
P. A. Thacker
Keyword(s):  
Pregnancy Rate ◽  
Reproductive Performance ◽  
Treatment Effect ◽  
Poor Performance ◽  
The Mean

AbstractIn four experiments, 189 gilts either received PMSG antiserum around the time of a PMSG- (experiments 1, 2 and 3) or PMSG/hCG-induced (experiment 4) oestrus or served as controls. Ovulation rates were not affected by treatment. There was no treatment effect on pregnancy rate (experiments 2, 3 and 4). In experiment 2, numbers of embryos in PMSG-treated control gilts were quite low and were higher (P < 0·05) in those gilts subsequently receiving anti-PMSG treatment. In experiment 3, the mean number of embryos in control gilts were higher than in experiment 2 and there was no effect of immunoneutralization of PMSG. No treatment effect was evident in PMSG/hCG treated gilts (experiment 4). These data indicate that the immunoneutralization of PMSG is unlikely to improve the reproductive performance of gilts following a gonadotropin-induced oestrus except in gilts that otherwise would have poor performance.

scholarly journals Outcome of GnRH antagonist ICSI cycles triggered by GnRH agonist plus Recombinant hCG versus triggered with Recombinant hCG alone in fresh autologous ICSI cycle

2020 ◽  
Vol 10 (1) ◽  
pp. 119-131
Author(s):  
Wafaa Mohammed Abed ◽  
Mohammed Oda Selman
Keyword(s):  
Pregnancy Rate ◽  
Oocyte Maturation ◽  
Standard Dose ◽  
Statistical Significance ◽  
Control Group ◽  
Infertile Women ◽  
Final Oocyte Maturation ◽  
Reproductive Techniques ◽  
The Mean ◽  
The Difference

To explore whether dual triggering for final oocyte maturation using a low dose of recombinant human chorionic gonadotropin (hCG) plus gonadotropin-releasing hormone agonist (GnRH-a) is as effective as the standard dose of recombinant hCG triggering alone in term of a total number of retrieved oocytes, fertilization and pregnancy rate in fresh autologous antagonist intracytoplasmic sperm injection (ICSI) cycles. 80 infertile women undergoing ICSI, aged ˂ 40 years, 18˂ Body mass index ˂30 Kg/m2 included in fresh autologous antagonist ICSI cycles. 40 women received a Standard dose of recombinant hCG (500 µg) alone and 40 women received GnRH-a (0.2 mg triptorelin plus 250 µg recombinant hCG) were used for final oocytes maturation. This study was conducted at the High Institute for Infertility Diagnosis and Assisted Reproductive Techniques, Al Nahrain University. The mean total number of retrieved oocytes, fertilization, and pregnancy rate were measured. The mean total oocyte number being statistically higher in the dual trigger group. The mean number of fertilized oocytes and clinical pregnancy rates was higher in the dual trigger group than in the control group, but the difference showed borderline statistical significance. Furthermore, fertilization rates show no statistical difference between the control group and the dual trigger group. Results of the study confirm that dual triggers show favorable improvement in fresh autologous antagonist ICSI cycles with the use of GnRH agonists plus hCG compared with hCG alone for triggering of final oocyte maturation.

Effects of melatonin implantation on the fertility potentials of Kivircik and Charollais ewes and rams during the non-breeding season

2017 ◽  
Vol 20 (3) ◽  
pp. 501-506 ◽  
Author(s):  
M. Cevik ◽  
C. Yilmazer ◽  
A. Kocyigit
Keyword(s):  
Pregnancy Rate ◽  
Breeding Season ◽  
Reproductive Performance ◽  
Reproductive Potential ◽  
Testicular Volume ◽  
Melatonin Treatment ◽  
Scrotal Circumference ◽  
Estrus Response

AbstractThis study examined the effect of melatonin implantation during the non-breeding season on the reproductive performance of ewes and the testicular dimensions of rams. In seasonally anestrus Kivircik and Charollais ewes and rams were subjected to melatonin. Estrus response was significantly higher in treated than control ewes of both breeds (p<0.001). The pregnancy rate was significantly lower (p<0.001) in the control than in the treated animals. The twinning rate was significantly lower in melatonin implanted Kivircik than Charollais ewes (p<0.05). The testicular dimensions after 42 days of melatonin treatment increased in both breeds. Scrotal length (SL) increased in Kivircik and Charollais rams (p<0.01). The increase in scrotal circumference (SC) was more marked in the Charollais (P<0.01) than in the Kivircik rams. There was a large increase in testicular volume (TV) in both Kivircik (p<0.01) and Charollais (p<0.001) rams. This study shows that melatonin implants can be applied to induce estrus in ewes approximately four months earlier than breeding season. Melatonin implantation in the non-breeding season significantly increased testicular dimensions in Kivircik and Charollais rams thus increasing their reproductive potential.

Observations on the effect of protein intake and stage of gestation on the proportion of urinary nitrogen excreted as urea in sheep

1973 ◽  
Vol 80 (3) ◽  
pp. 363-368 ◽  
Author(s):  
J. J. Robinson ◽  
D. Scott ◽  
C. Fraser
Keyword(s):  
Protein Intake ◽  
Late Gestation ◽  
Direct Result ◽  
Ewe Lambs ◽  
Low Protein ◽  
The Mean ◽  
The Difference ◽  
Pregnant Ewe ◽  
N Requirement ◽  
Urinary Nitrogen

SummaryThe effect of altering the level of protein intake on urea excretion in ewes was assessed in two separate experiments.In Expt 1, 14 pregnant (during the last 20 days of gestation) and 10 non-pregnant ewes were each offered a different level of digested N intake in the range 5–25 g/day. At all levels of protein intake urea N excretion was lower in pregnant than in nonpregnant ewes.In Expt 2, 21 pregnant ewe lambs were each offered one of three diets supplying mean intakes of 83 (T1), 113 (T2) or 147 (T3) g crude protein/day. During the last 100 days of gestation the mean levels of urea N excretion were 6·9, 11·0 and 15·2 g/day for T1, T 2 and T 3, respectively. The corresponding values for urinary N excretion were 9·3, 13·8 and 18·2 g/day. At all levels of protein intake urea N excretion was lower just prior to parturition than 95 days prepartum; the difference was correlated with lamb birth weight and maternal body-weight change.A notable feature of both experiments was the low level of urea N excretion by the pregnant ewes in late gestation, at low protein intakes. It would appear that when energy intake is adequate the decrease in urea N excretion associated with pregnancy is a direct result of an increased N requirement for maternal and/or foetal growth.

The effect of implantation of lowland ewes with melatonin on the time of mating and reproductive performance

1992 ◽  
Vol 54 (1) ◽  
pp. 31-39 ◽  
Author(s):  
W. Haresign
Keyword(s):  
Dose Level ◽  
Litter Size ◽  
Reproductive Performance ◽  
Melatonin Treatment ◽  
Mating Period ◽  
Mating Patterns ◽  
Lower Dose Level ◽  
The Mean

AbstractTwo trials, involving a total of 1006 Mule ewes and 1862 Suffolk-× ewes, were conducted to investigate the ability of implantation with melatonin to induce early breeding in lowland sheep flocks. Dates of implantation ranged from mid May to late June for Suffolk-× flocks and mid May to early July for Mule flocks.From the mating patterns obtained it is suggested that the optimum implantation date is mid May to mid June for Suffolk-× ewes and mid June to mid July for Mule-type ewes.Melatonin treatment also significantly increased the mean litter size per ewe exposed to the ram (resulting from a 6-week mating period) when the data were pooled across flocks, but the magnitude of this effect varied across flocks. Part of this overall mean increase in Mule ewes (+0·84 and +0·50 extra lambs per ewe in trials 1 and 2 respectively) was due to an increase in the proportion of ewes mating and lambing and part of it (+0·13 and +0·17 extra lambs per ewe, respectively) was due to an increase in litter size per ewe pregnant. In the Suffolk-× ewes there was evidence that the overall mean benefit following implantation with two implants (+0·31 extra lambs per ewe) was greater than that following implantation with one implant (+0·14 extra lambs per ewe), with all of the increase at the lower dose level and +0·21 extra lambs per ewe at the higher dose being due to an increase in litter size per ewe pregnant.

Reproductive performance at first lambing and in twice-yearly lambing in a flock of Finnish Landrace sheep in Finland

1977 ◽  
Vol 25 (3) ◽  
pp. 319-329 ◽  
Author(s):  
H. Goot ◽  
K. Maijala
Keyword(s):  
Litter Size ◽  
Reproductive Performance ◽  
Conception Rate ◽  
Land Race ◽  
Commercial Flock ◽  
The Mean

SUMMARY1. The reproductive performance of 128 first-lambing ewes born during 1966–71, and of 118 ewes kept on a twice-yearly lambing system during 1968–1972/73, in a commercial flock of Finnish Land-race sheep in Finland, was analysed.2. The first-lambing ewes were exposed to the ram throughout the year, except in June and July. Out of 95 ewes born between January and May, 92 (97%) lambed at the age of 376·4 ± 29·9 days, and out of 20 born between July and September, 15 (75%) lambed when 323·8 ± 50·4 days old.3. The average litter sizes at first lambing were 1·6, 1·9 and 2·6 for ewes with average ages of 324, 388 and 534 days, respectively; the 5-mo litter weights averaged 41·7, 45·7 and 70·5 kg per ewe for the three groups.4. In the twice-yearly lambing system 55% of ewes lambed once within a calendar year and 45% lambed twice. The number of consecutive lambings and the number of lambs born per ewe per year were 1·52 ± 0·29 and 4·03 ± 1·18, respectively. The consecutive lambings of the 118 ewes, over a period of 1½ to 5½ yr, did not indicate any decline in reproductive performance.5. The estimated lambing-to-conception interval in consecutive lambings was 116·6 ± 64·3 days; February had the lowest conception rate (0·7%) and November the highest (20·8%); April (16·5%) and September (15·5%) were similar.6. Litter size was not affected by year, age of ewes, or lambing period. The mean lamb mortality up to 14 days of age, based on 1168 lambs born dead or alive, was 12·8% and the annual ewe wastage averaged 21·9%7. For ewes which lambed twice within a calendar year, the lambing to conception interval was 71·7 ± 24·7 days. Such ewes produced 5·0±1·4 lambs per calendar year and the combined 5-mo weight of both litters was 168·2 ± 43·2 kg per ewe.

Reproductive performance during early pregnancy in cattle with contrasting early pregnancy rates

2001 ◽  
Vol 26 (2) ◽  
pp. 283-288
Author(s):  
W.H McMillan ◽  
A J. Peterson ◽  
S.F. Cox ◽  
S.J. Pearson ◽  
M.J. Donnison
Keyword(s):  
Pregnancy Rate ◽  
Embryo Transfer ◽  
Early Pregnancy ◽  
Reproductive Performance ◽  
Oestrous Cycle ◽  
Interferon Tau ◽  
Protein Levels ◽  
Reactive Protein ◽  
The Difference ◽  
Establishment Phase

AbstractCauses of variation amongst cattle within a herd in their ability to initiate and maintain pregnancy are largely unknown. An experimental animal resource has recently been established to understand the biology of early reproductive performance. This paper summarises the results achieved during the establishment phase and from several experiments aimed at determining the physiological basis of the difference between sub-herds of contrasting pregnancy rates on Day 60. Each of 155 contemporary yearling heifers received 2 in vitro-produced embryos on 6 separate occasions during a 26-month period. Sixty days after transfer, pregnancy and twinning rates were determined ultrasonically, pregnancies terminated and the process repeated. The interval between successive transfers was greater than 100 days. Heifers were ranked on their aggregate pregnancy rate performance after 6 rounds of transfer, and the highest (High) and lowest (Low) 25 were retained. Differences in reproductive performance during the establishment phase of the herd are reported. In addition, several subsequent experiments examined ovarian follicle turnover and progesterone levels during an oestrous cycle, early embryo development after either AI or embryo transfer, and protein, interferon tau and ubiquitin-cross-reactive protein levels in uterine luminal flushings.Pregnancy rates were 7-folder higher in the High sub-herd (76 vs. 11%), with much of this difference apparent by Day 25. The proportion of heifers observed in standing oestrus prior to embryo transfer and the interval from the end of synchronisation treatment to the onset of oestrus were similar in the sub-herds. Oestrous cycle length, ovarian follicular dynamics and progesterone profiles during the oestrous cycle were also similar. More conceptuses had elongated by Day 14 in the High sub-herd (67 vs. 14%, P<0.05), which also tended to have a higher pregnancy rate after artificial insemination (52 vs. 29, P<0.1). Total protein in flushings from the uterus was similar in the sub-herds on Day 14 and Day 17. Conceptuses in the High sub-herd were longer on Day 17 following embryo transfer (6.5 vs. 4.8, P<0.05). Interferon-tau levels were higher in the High sub-herd (25.9 vs. 16.1, P<0.01), although ubiquitin cross-reactive protein levels were also higher in the High sub-herd, but this difference just failed to reach significance. We conclude that: 1. Most of the difference in sub-herd pregnancy rate occurs within 3 weeks of ET; 2. Ovarian factors are unlikely to contribute to the difference; 3. Major differences occur after blastocyst hatching and probably depend upon a differing endometrial environment before Day 14; 4. Differences in the ability of the uterine milieu to stimulate the expression of interferon-tau may be responsible for the differences in pregnancy rate; 5. The two sub-herds are a unique experimental resource for understanding early pregnancy in cattle following either AI or ET.

Milk progesterone profiles during anoestrus through to pregnancy in Greek dairy goats (Capra prisca): the effect of melatonin treatment and male introduction

1993 ◽  
Vol 56 (3) ◽  
pp. 333-339 ◽  
Author(s):  
S. Belibasaki ◽  
D. Zygoyiannis ◽  
P. Davies ◽  
J. M. Doney
Keyword(s):  
Oestrous Cycle ◽  
Sexually Active ◽  
Progesterone Concentration ◽  
Dairy Goats ◽  
Melatonin Treatment ◽  
The Mean ◽  
The Difference ◽  
Mean Time ◽  
Mean Concentration ◽  
Stimulation Of

AbstractTwo groups of 10 lactating does were housed separately, in isolation from bucks. Does in one group (T) were implanted with melatonin; the second group (U) were not implanted. After 30 days, five implanted and five non-implanted bucks were introduced, singly, into both groups of females each day. Subsamples of milk were taken from the daily output of each doe on 3 days each week for progesterone analysis.Mean milk progesterone concentration during anoestrus varied significantly amongst individuals (P < 0·001), but the difference between T and U groups was not significant (1·51 and 1·93 (s.e.d. 0·52) μg/l, respectively). Elevated progesterone levels, indicative of a short oestrous cycle and commencing days 2 to 5 after male exposure, were observed in most does. Mean progesterone concentrations were 9·9 and 9·6 (s.e.d. 1·32) μg/l in T and U does respectively. Most does showed a second short cycle starting at 12 to 18 days, (mean concentration 8·4 and 10·6 (s.e.d. 1·64) ng/l, respectively). Untreated does then returned to anoestrus until mated at 63·1 (s.e. 0·94) days after male introduction. In contrast, T does either became pregnant or had a normal oestrous cycle, followed by a repeat cycle or pregnancy (mean onset 21·7 (s.e. 2·22) days after male introduction). The mean time of effective mating for group T does was 37·3 (s.e. 5·91) days, 26 days earlier than for U does (P < 0·001). Mean progesterone concentration in early pregnancy was 65·7 (s.e. 5·78) and 67·6 (s.e. 5·41) μg/l in T and U does, respectively. Males did not become sexually active until after the onset of luteal activity in the females, although treated males were earlier than untreated. There were no significant differences in lactation pattern associated with the progesterone profiles in the two groups.The introduction of males during late anoestrus initiates short luteal cycles. Only those does closest to onset of the breeding season, in this case induced by melatonin, continue to cycle normally and mating success may require early stimulation of sexual activity in males.

Sign in / Sign up

Export Citation Format

Share Document