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1.
Contents
Fifty-nine female yearlings of local Awassi sheep were randomly divided into two groups. Animals in group T (treated) were fitted with intravaginal sponges containing 60 mg of medroxyprogesterone acetate for 14 days followed by 400 IU of pregnant mare's serum gonadotrophin (PMSG) at sponge withdrawal, whereas group C (control) received no treatment. Oestrus rate was 92.7 and 11.2% for groups T and C, respectively. Lambing rate was 78 and 5.6% for groups T and C, respectively. Twinning rate was 31.3% in group T compared to zero in group C. Average birth weight for single born lambs (4.7 ± 0.6 kg) was significantly (p < 0.05) higher than twin born lambs (3.0 ± 0.5 kg) in group T. The average concentration of blood progesterone collected between days 17–19 after mating was 19.30 nmol/l and the accuracy of early pregnancy diagnosis was 100%. It was concluded that, it is possible to induce synchronized oestrus, and to increase the twinning rate in Syrian Awassi sheep yearlings outside the breeding season, using intravaginal sponges and PMSG. In addition, early pregnancy diagnosis could be successfully determined in female Awassi sheep yearlings between days 17–19 after mating.  相似文献   

2.
An experiment was conducted to examine the effect of progesterone prior to a GnRH‐PGF2α treatment on oestrus and pregnancy in seasonally anoestrous Awassi ewes. Twenty‐four ewes were randomly assigned to three groups to be pre‐treated with 60 mg medroxyprogesterone acetate sponges (group A), 600 mg progesterone sponges (group B) or blank sponges (group C) for 4 days. All ewes were injected with 100 μg of GnRH 24 h after sponge removal followed, 5 days later, by 20 mg PGF2α injection. Ewes were exposed to three fertile rams at the time of PGF2α injection (day 0, 0 h) and were checked for breeding marks at 6‐h intervals for 5 days. Blood samples were collected from all ewes 1 day (day ?10) prior to sponge insertion, at the time of sponge removal (day ?6), 1 day following sponge removal (day ?5, at the time of GnRH injection) and at the time of PGF2α injection (day 0) for analysis of progesterone. Progesterone concentrations on days ?10 and ?5 were basal and averaged 0.2 ± 0.04 and 0.2 ± 0.2 ng/ml, respectively. Progesterone concentrations on day ?6 were elevated only in group B ewes and were higher (p < 0.0001) than those of groups A and C. Progesterone concentrations on day 0 were higher (p = 0.002) in groups A and B than group C. Oestrous responses occurred only in ewes of groups A and B (p > 0.05). Induced oestrus conception rate was greater (p < 0.01) in group A than groups B and C. Ewes returned to oestrus 17–20 days following day 0 were two of eight, six of eight and three of eight of groups A, B and C, respectively, all of which eventually lambed. The overall lambing rate was 82% in progesterone‐primed ewes compared with only 38% non‐progesterone‐primed ewes (p < 0.05). Progesterone priming apparently sensitizes GnRH‐PGF2α‐treated seasonally anoestrous ewes and increases their response in oestrus and pregnancy rates.  相似文献   

3.
The aim of this study was to investigate characterization of oestrous response, onset of induced oestrus, oestrous duration, fecundity and fertility in Awassi ewes treatment with intravaginal sponges and Controlled Intravaginal Drug Release (CIDR) devices in combination with pregnant mare serum gonadotropin (PMSG) under local environmental conditions during the non‐breeding season. A total of 62 ewes were divided into three groups. Group CIDR (n = 20) was treated with CIDR devices for 12 days and 400 IU PMSG was injected upon removal of the CIDR. For ewes in Group Sponge (SP) (n = 24), 30 mg fluorogestone acetate was administered to the sheep for 12 days and 400 IU PMSG was injected upon withdrawal of the sponge. Group Control (CON) (n = 18) served as a control group and received no treatment. Adult, intact and sexually experienced Awassi rams were introduced to all groups at the time when the intravaginal devices were removed. There were no significant differences in terms of oestrous response (CIDR: 90%, SP: 87.5%), time to onset of oestrus and duration of induced oestrus between the CIDR and SP groups. The oestrous response of treatment groups was significantly greater (p < 0.05) than in the control ewes. There were no significant differences in pregnancy (CIDR: 70%, SP: 70.8%), lambing (CIDR: 85%, SP: 79.2%) and fecundity rates between ewes treated with CIDR and those treated with sponges. However, pregnancy and lambing rates were significantly (p < 0.05) higher in ewes treated with CIDR or sponges when compared with those in the control group. It was concluded that it is possible to induce fertile oestrus, successful pregnancy and lambing with the treatment of either CIDR or intravaginal sponge in combination with PMSG in Awassi ewes during the non‐breeding season.  相似文献   

4.
One hundred eighty-nine Corriedale ewes were used during the non-breeding season to study the "ram effect" stimulus after priming with progestogens. Intravaginal sponges containing either medroxyprogesterone acetate (MAP group, n = 49), fluorogestone acetate (FGA group, n = 49), or progesterone devices (CIDR group, n = 46) were inserted on Day-6 (Day 0 = introduction of the rams). Forty-five ewes were untreated and kept as a control group. On Day 0 the sponges were removed and rams provided with marking harnesses for oestrous detection were placed with the ewes. Onset of estrus was monitored until Day 25, and conception was determined by transrectal ultrasonography. Ewes came into heat during 4 periods: Days 0-3, 5-7, 17-20, and 21-23. The overall number of oestrus ewes were 29%, 53%, 35%, and 50% for the control, MAP, FGA, and CIDR groups, respectively (MAP and CIDR > control, p < 0.05). Control ewes presented oestrus only on Days 17-20 and 21-23. Oestrus in the progestogen-primed ewes was concentrated during Days 0-3 and 17-20, and some ewes came into oestrus on Days 5-7. There were no differences between different primings neither in oestrous response nor in conception rate. The conception rate from matings occurring on Days 0-3 was higher than on those occurring on Days 17-20. We conclude that MAP, FGA, and CIDR is equally effective in improving the response to the ram effect, and the pattern of oestrus in primed ewes was different than previously reported.  相似文献   

5.
The intensity of heat signs in buffaloes is generally low and the incidence of suboestrus varied from 15 to 73% (Buffalopedia). The objective of this study was to investigate the feasibility of monitoring the changes in some milk constituents, oestradiol levels and electrical conductivity of vaginal mucus during peri‐oestrous period in prediction of the timing of oestrus in buffaloes. Twenty‐one Egyptian buffaloes aged 3–9 year, 1st–6th lactations, were examined by oestrous detector and ultrasonographically for monitoring the ovarian and uterine activity for 7 days around the time of standing oestrus. Sodium, potassium, chloride and lactose were assayed in aqueous phase of milk; besides, oestradiol was estimated in serum. Current results declared highly significant acute changes in milk constituents at the time of oestrus characterized by peaking of chloride and sodium levels and lowering of potassium and lactose values. The alternation in milk composition when arranged in decreasing order of magnitude, sodium was the highest (77.78 ± 0.69%), followed by chloride (61.60 ± 1.52%) and potassium (?58.14 ± 10.89%). Concomitantly, milk lactose decreased by 26.07 ± 7.97% compared to baseline levels. Synchronously, vaginal electrical resistance (VER) showed a significant (p < 0.01) decrease, but serum oestradiol 17β levels surged (59.93 ± 7.29 pg/ml) on day of oestrus. Serum oestradiol level was negatively correlated with VER (r = ?0.577), potassium (r = ?0.661), positively correlated with chloride (r = 0.707) and sodium (r = 0.579) and not correlated with lactose levels. These results for the first time suggested that the changes in constituents of milk during peri‐oestrous period may be used as a practical non‐invasive indicator for oestrous detection and prediction of ovulation in Egyptian buffaloes.  相似文献   

6.
This study aimed to evaluate the effect of oestrous synchrony between donors and recipients and the embryo quality on the pregnancy rate in beef cow recipients. The experiment was performed over two years at an embryo transfer (ET ) centre in Southern Brazil. Ninety Aberdeen Angus cows were subjected to superovulation (SOV ) protocols, resulting in the recovery of 1,048 transferable embryos. Eleven groups were formed with intervals of 6 hr, from ?30 to +30 hr, with respect to recipient versus donor oestrous detection. Evaluation of embryo quality was according to the IETS guidelines. The overall pregnancy rate was 52%. Effects related to donor and recipient oestrous synchronization on pregnancy rate were observed (p  =  .01), ranging from 36% to 50%. The embryo quality rate affected the pregnancy rate, where Grade I resulted in 57% and Grade III in 43% of pregnancy (p  <  .001). The embryonic state (frozen or fresh) showed no (p  >  .05) effect on pregnancy rate: 53% for fresh embryos and 44% for frozen embryos. The odds ratio for explanatory variables causing pregnancy indicated that Grade III embryos had 31% less chance of conception compared to Grade I. Thus, oestrous synchrony between donor and recipient, considering ±30 hr apart, can affect the pregnancy rate along with embryo quality.  相似文献   

7.
The effect of a modified eros centre on weaning to oestrus interval, follicle size, ovulation and farrowing rate and total born litter size was investigated. In modified eros centre 94.4% and in group housing 79.1% of the sows (p < 0.01) expressed oestrus within 10 days post‐weaning. Weaning to oestrus interval was shorter (p < 0.001) for sows kept in modified eros centre. The interval from onset of oestrus to the time of ovulation was longer for sows in group housing (p=0.05). The time of ovulation was negatively correlated (r=?0.50) with the interval from weaning to oestrus (p=0.005). The time of ovulation after onset of oestrus was significantly (p < 0.05) shorter for sows expressing oestrus within 2–4 days of weaning, compared with the animals that expressed oestrus between days 5 and 6 post‐weaning and was shortest for sows expressing oestrus after day 6 post‐weaning. Farrowing rate was not affected by a modified eros centre. Litter size tended to be smaller in group‐housed weaned sows (p=0.10). The timing of last artificial insemination relative to time of ovulation did not affect litter size (p > 0.10). The implication of these results is that a modified eros centre may improve some of the post‐weaning oestrous parameters of the sow.  相似文献   

8.
This study examined the extent to which prolonged farrowing and parity are associated with plasma oxytocin concentrations and follicular development of oestrous sows during subsequent insemination. A total of 30 sows were allocated to two groups based on farrowing duration: (i) SHORT (n  = 14): 159 ± 29 min, (ii) LONG (n  = 16): 533 ± 190 min. The sows were also divided into two parity classes: (i) YOUNG (n  = 14): parity 2.5 ± 0.8, (ii) OLD (n  = 16): parity 6.4 ± 2.3. After weaning, the ovaries were examined daily with transrectal ultrasound. On the second day of oestrus, blood samples were collected for oxytocin (OT ) assay at ?15, ?10, ?5, 0, +1, +2, +3, +4, +6, +8, +10, +15, +20, +25, +30, +40, +50 and +60 min with a boar contact between 0 and +10 min. Boar presence stimulated an increase in OT concentrations (p  <  .05). During boar presence, OT in the LONG group was higher than in the SHORT group (p  <  .01). The sows in the OLD group had a longer farrowing duration than in the YOUNG group (p  <  .05). OT levels and diameters of follicles were more relevant for parity than was the duration of farrowing. We therefore conclude that the OT levels and follicular development of oestrous sows are associated due to parity but difficult to be predicted from the duration of previous farrowing.  相似文献   

9.
The aim of this trial was to evaluate the effectiveness (fertility and lambing) of priming with a single injection of progesterone plus PMSG in anovulatory lactating Sarda ewes subjected to the ram effect (RE) in spring. Thirty ewes (P4 group) were i.m. injected with 30 mg progesterone and 500 IU PMSG 36 h before ram introduction (d 0). This treatment was compared to a 12-day treatment with fluorogestone acetate intravaginal sponges that was followed by injections of 350 IU PMSG upon sponge withdrawal (FGA group, n=30). All ewes responded to RE, showing plasma progestrone concentrations >1 ng/mL between d 6 and 12 (FGA) or 6 and 9 (P4). Eighty-nine percent of the P4 ewes conceived at first ovulation, and 11% conceived following a short estrus cycle. Lambings occurred on d 150.4 +/- 3.9, and the lambing rate was 100%. The fertility of the FGA ewes was 83% for the induced ovulation and was 7% for the second ovulation after a normal cycle. The FGA ewes lambed on d 149.8 +/- 4.4, and the lambing rate was 83%. Two abortions were recorded for the FGA ewes, which had higher prolificacy than the P4 group (2.2 +/- 0.8 vs. 1.8 +/- 0.4, respectively; P<0.05). Both fertility and the lambing rate were high in both groups, with a high degree of estrus synchronization, and there were no significant differences between the groups. We concluded that priming of lactating Sarda ewes in spring with P4+PMSG before RE is an effective and competitive method (cheaper and more practical than FGA+PMSG) of inducing fertile ovulations in these ewes.  相似文献   

10.
SUMMARY Effects of body weight, condition score, ovarian cyclic status and insemination regimen on pregnancy rates were investigated in 164 Bos indicus heifers synchronised with norgestomet-oestradiol and pregnant mare serum gonadotrophin (PMSG). Oestrus detection techniques were also compared. Heifers were inseminated at either a fixed time (group 1, n = 83) of 48.0 ± 0.2 h (mean ± SEM) after implant removal or at 8.9 ± 0.5 h after oestrus was detected (group 2, n = 81). Group 2 heifers that were not detected in oestrus by 72 h after implant removal were inseminated at that time. Oestrus was detected for the purpose of insemination using heatmount detectors. Tail-paint and oestrogen treated, chin-ball harnessed steers were used to compare the efficiency of oestrus detection. The probability of ovarian cyclicity increased with increasing body weight and condition score (P < 0.001). A higher proportion of heifers that were acyclic at the commencement of treatment, compared with cyclic heifers, were detected in oestrus at the time of insemination in the fixed-time inseminated group (P <0.01). Analysis of covariance revealed that intervals from implant removal to oestrus were influenced by ovarian cyclic status (P < 0.01) and insemination group (P < 0.05). A higher pregnancy rate (%± SEM) was obtained in acyclic compared with cyclic heifers in the group 1 heifers (50.0 ± 10 vs 28.1 ± 6; P = 0.055) but not among the group 2 heifers (45.8 ± 10 vs 49.1 ± 7; P = 0.787). The probability of pregnancy was found to be associated negatively with body weight (P = 0.01) while a higher pregnancy rate was obtained in the group 2 compared with group 1 heifers (48.2%vs 34.9%; P = 0.093). The efficiency of oestrus detection was highest using heatmount detectors compared with tail-paint and chin-ball harnessed steers (90.7%vs 37.0% and 23.5%, respectively; P < 0.0001). We conclude that pregnancy rates can be increased in extensive environments when insemination follows oestrus detection using heatmount detectors compared with a fixed-time insemination. The fertility of heifers inseminated at a fixed time is influenced by ovarian cyclic status due to its influence on oestrus-to-insemination intervals.  相似文献   

11.
This was an observational study of 828 lactations in 542 mixed‐age dairy cows that calved seasonally in a single, pasture‐fed herd in New Zealand in 2008 and 2009. The study objectives were to: (i) document daily liveweight change (?LW) before and after observed oestrus for cows subsequently diagnosed pregnant or non‐pregnant and (ii) quantify the sensitivity and specificity of ?LW as a test for oestrus. The sensitivity and specificity of ?LW when combined with other commonly used oestrous detection methods was also evaluated. In cows that conceived as a result of service at detected oestrus, liveweight loss began 1 day before the day of detection and was greatest on the day of detection (?9.6 kg, 95% CI ?11.3 kg to ?7.8 kg; p < 0.01) compared with LW recorded 2 days before the day of detection. In cows that did not conceive to a service at a detected oestrus, the lowest liveweights were recorded 1 day before the day oestrus was detected (?4.3 kg, 95% CI ?7.7 to ?0.8 kg; p = 0.02) compared with LW recorded 4 days before the day of detection. The sensitivity and specificity of ?LW as a means of oestrous detection were 0.42 (95% CI 0.40–0.45) and 0.96 (95% CI 0.95–0.97), respectively. When ?LW was combined with tail paint and visual observation, the oestrous detection sensitivity and specificity were 0.86 and 0.94, respectively. Monitoring LW change holds promise to enhance the sensitivity and specificity of oestrous detection in combination with other oestrous detection methods.  相似文献   

12.
This study aimed to elucidate the effects of repeated pregnant mare serum gonadotropin (PMSG) treatment for oestrous synchronization (ES) on ovarian gene expression and reproductive parameters in Xinong Saanen dairy goats, the dominant breed of dairy goat in China. The experiment was carried out at the Research Station of Northwest A&F University (NWAFU), China (34°16′N, 108°4′E). Forty‐one does were randomly assigned to groups receiving ES treatments thrice every fortnight (3‐PMSG group; n = 19), or ES treatment only once simultaneously with the third ES treatment in the 3‐PMSG group (1‐PMSG group; n = 22) during middle of the breeding season from late July (14 hr light) until late September (12 hr light). ES treatment was performed via intravaginal insertion of a controlled internal drug release (CIDR) device impregnated with 300 mg progesterone (P4), followed by 300 IU PMSG injections 48 hr before CIDR withdrawal. Oestrus was monitored using vasectomized bucks. Ovaries of three goats in oestrus from both groups were harvested for morphological examination and RNA sequencing (RNA‐Seq). Then, all the oestrous goats in the 1‐PMSG (n = 21) and 3‐PMSG (n = 11) groups were artificially inseminated twice. The 3‐PMSG group showed reduced oestrous rate (57.89%), pregnancy rate (31.58%) and litter size (1.17) compared, respectively, with 95.45%, 68.18% and 1.67 for 1‐PMSG group (p < 0.05). However, no differences were found in the ovarian morphology between the 1‐PMSG and 3‐PMSG groups (p > 0.05). RNA‐Seq revealed 114 differentially expressed genes (DEGs) in the ovaries of the 3‐PMSG group, among which GCG, FSTL3, TET3 and AQP3 were deemed novel and promising candidate genes for regulating fertility. The present study indicates that the three‐time PMSG treatment dysregulated several ovarian genes, thereby reducing reproductive performance.  相似文献   

13.
Objectives of this study were to characterize patterns of follicular development in sheep superovulated with purified follicle stimulating hormone (FSH) (OVAGENTM, ICP, Auckland, New Zealand) and to determine its influence on preovulatory events (onset of the oestrus behaviour and timing of the preovulatory luteinizing hormone surge) and ovarian response (ovulation rate and embryo yield). Number and size of all ≥ 23 mm follicles from the first FSH injection to withdrawal of progestagen sponges was determined by transrectal ultrasonography just prior to every FSH injection in nine Manchega ewes superovulated with eight decreasing doses (ml) (1.5 × 3, 1.25 × 2 and 1 × 3) of OVAGEN injected twice daily from 60 h before to 24 h after the withdrawal of 40 mg fluorogestone acetate sponges. Oestrous detection and jugular blood sampling for LH radioimmunoassay were performed every 3 h from 14 to 53 h after sponge removal and ovulation rate and number of embryos were determined 4 days after progestagen withdrawal. Administration of OVAGEN induced a significant rise (p < 0.0005) in the number of follicles ≥ 4 mm in size because of an increased growth in size of follicles from the first FSH injection to sponge removal, an increase in the number of newly detected follicles from 12 to 36 h of the first FSH dose (p < 0.005) and a decrease in regression rate from 24 h (p < 0.001). The number of follicles 2–3 mm in size at first FSH dose (10.4 ± 1.5) was positively correlated with the number of ≥ 4 mm follicles at 0 h (19.0 ± 2.7, p < 0.01). A higher number of ≥ 4 mm follicles at 0 h was related with an earlier appearance of oestrus (31.5 ± 1.5 h, p = 0.08) and LH surge (45.0 ± 2.3 h, p < 0.005), and a higher ovulation rate (18.2 ± 3.8, p < 0.005). On the other hand, the rate of embryo recovery was decreased in ewes with earlier preovulatory LH peaks (p < 0.005), with a shorter interval between oestrus and LH peak (p < 0.05).  相似文献   

14.
Difficulty in observing oestrus is a problem for many dairy farmers performing AI. Finding ways to synchronize oestrous cycles or strengthen display of oestrus without hormonal treatments would be of great interest because many consumers object to the use of exogenous hormones on healthy animals. Modification of reproductive cycles through chemical communication has been reported in several species including cattle. LH is an important regulator of the follicular phase and could possibly be subject to pheromonal influence. This study focuses on the effect of volatile compounds from oestrous substances on LH pulsatility preceding the preovulatory LH surge in cattle. Four heifers of the Swedish Red breed were kept individually in isolation. Exposure to water during the control cycle (CC), and bovine oestrous urine and vaginal mucus during the treated cycle (TC), started simultaneously with induction of oestrus. Blood sampling at 15‐min intervals started 37 h after administration of PGF2α and continued for 8 h. Monitoring of reproductive hormones, visual oestrus detection and ultrasonographic examination of the ovaries continued until ovulation had occurred. The mean concentration of LH at pulse nadir was significantly higher during TC (2.04 ± 0.18 ng/ml) than during CC (1.79 ± 0.16 ng/ml), and peak amplitude was significantly higher during CC (Δ1.03 ± 0.09) than during TC (Δ0.87 ± 0.09). No other parameters differed significantly between the two cycles. We conclude that the difference in LH pulsatility pattern may be an effect of exposing heifers to oestrous vaginal mucus and/or urine and that the mechanism behind this needs further investigation.  相似文献   

15.
The aim of this study was to determine phospholipase A2 (PLA2) kinetics and activity in the mare’s endometrium during the oestrous cycle and early pregnancy. Phospholipase A2 is responsible for the liberation of arachidonic acid from phospholipids, which is the first limiting step in prostaglandins synthesis. Phospholipase A2 activity was measured using an assay based on the liberation of oleic acid from 1‐palmitoyl‐2‐[14C] oleoyl phosphatidylcholine. The enzyme was shown to be calcium dependent, to have an optimum pH of 8 and an apparent Michaelis constant of 127 μm . Enzyme activity was low in the endometrium of early luteal phase tissue but increased significantly (p < 0.001) during the late luteal phase (5.39 ± 0.16; 3.48 ± 0.33, 6.85 ± 0.59, and 9.96 thinsp;± thinsp;1.23 thinsp;nmol oleic acid released/mg protein at oestrus, and Days 3, 8 and 14 after ovulation, respectively). The mean PLA2 activity in endometrial tissue from pregnant mares (4.23 ± 0.74) was significantly lower (p < 0.01) than from cyclic animals during late dioestrus (9.96 ± 1.23). The results indicate that PLA2 activity in equine endometrium changes with the stage of the oestrous cycle and thus may be influenced by systemic hormone concentrations. The inhibitory effects of conceptus products on secretion of prostaglandin during early pregnancy were associated with a competitive inhibitor that decreased endometrial PLA2 activity.  相似文献   

16.
Oestrus synchronisation, fertility and kidding behaviour were studied in 44 Black Bengal goats. They were divided into six experimental groups: group 1, control; group 2, progesterone; group 3, progesterone, pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG); group 4, prostaglandin F2 alpha (PGF2 alpha); group 5, PGF2 alpha, PMSG and HCG; group 6, PMSG and HCG. There was 100 per cent synchronisation of oestrus in the groups treated with progesterone, progesterone with PMSG and HCG, and prostaglandin with PMSG and HCG. In the other two treated groups the synchronisation was between 66 and 75 per cent. In the control group only 50 per cent of the animals came into oestrus during the period of observation. The duration of oestrus varied between 19 and 24 hours except in group 5 where it was 40.87 hours. Animals came on heat between 95 and 137 hours after treatment except in group 5 where the interval was only 18.87 hours. A maximum fertility of 75 per cent was observed in group 4 while the kidding percentage was greatest in group 2. There appeared to be no beneficial effect of superovulation on the number of kids produced. Gestation length was similar in all the groups.  相似文献   

17.
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.  相似文献   

18.
The objective of this study was to compare the efficiency of oestrus induction protocols on Kilis dairy goats kept on a goat farm situated close to Kilis, Turkey. Eighty goats were assigned randomly into four groups of 20 animals each in a factorial arrangement: (i) untreated control (CON), (ii) melatonin implant (MEL), (iii) CIDR-G (CIDR) and (iv) melatonin implant plus CIDR-G (MC). Experiments were performed in mid-anoestrus season under natural photoperiod environment. The differences among treatment groups in oestrus response were significant. Oestrus response was higher in the MC group than in other groups (p < 0.05). A significant difference was observed in the time interval from cessation of treatment to the onset of oestrus among treatments. The CIDR-G treatment reduced intervals from buck introduction to oestrus. The time to onset of oestrus in both the MC and CIDR groups was significantly shorter, compared with the MEL and CON groups (p < 0.05). The number of does kidding and fertility were not different among treatment groups (p > 0.05). Fecundity was similar among goats in all groups. Prolificacy and twining rates showed similar trends as fecundity rates, with no differences (p > 0.05) between treatments. The results of this study showed that oestrus in Kilis does can be effectively induced by using melatonin and CIDR combined treatment, and fertility will not be adversely affected. However, this treatment did not improve fecundity, prolificacy and twining rates.  相似文献   

19.
The effects of lipopolysaccharide ( Escherichia coli , O55:B5), administered 18 h after ovulation in the second oestrus after weaning on the hormonal profiles in 14 Swedish cross-bred (Landrace × Yorkshire) multiparous sows were studied. The endotoxin group (E-group) sows were administered with 300 ng/kg of lipopolysaccharide (LPS) whereas the control group (C-group) sows were administered 5 ml of saline intravenously via an indwelling jugular cannula. Blood samples for hormonal analyses were collected from all sows until slaughter. In the E-group, progesterone, cortisol and prostaglandin F2α metabolite levels increased significantly (p < 0.05) following LPS compared with the C-group. It can be concluded from this study that apart from elevating cortisol and prostaglandin F2α metabolite, LPS also elevates progesterone levels.  相似文献   

20.
The aim of this study was to examine the possible differences of oestrous intensity between natural oestrus and induced oestrus using the walking activity measuring device. Walking activity was used as an evaluation index of oestrous intensity. A total of 27 Japanese Black cows, more than 40 days after calving and clinically normal, were randomly assigned to three groups. Walking activity was recorded using a commercially available computerized pedometer system. The treatment groups consisted of an Ovsynch (n = 8) and a controlled internal drugs releasing device (CIDR) + Ovsynch (n = 9) group. The control group (n = 10) received no treatment. Walking activity was examined in all groups. Timed artificial insemination (timed AI) was performed at 16 hours after the onset of oestrus in the control group and at 24 h after second administration of GnRH in the treatment groups. Duration of oestrus had a tendency to be shorter in both the Ovsynch and the CIDR + Ovsynch groups when compared with the control group. The time required from the onset of oestrus to the time showing the highest number of steps of walking (the time to peak) showed a tendency to be shorter in CIDR + Ovsynch group. The number of steps of walking at peak and overall walking activities were significantly lower in both treatment groups than in the control group. Both activity and super-activity periods of time in the treatment groups were shorter than the control group. No difference was observed in the conception rate between the control (50.0%; 10/20), Ovsynch (50.0%; 4/8) and CIDR + Ovsynch groups (66.7%; 6/9). This study demonstrates that the oestrous intensity of cows in oestrus was different between natural oestrus and induced oestrus and also between the methods of the synchronization, but no difference was observed in the conception rate among the three groups.  相似文献   

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