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1.
In 160 cows with ovarian cysts as determined by rectal palpation, differentiation was made of follicular cyst, luteal cyst, and cystic corpus luteum on the basis of milk progesterone concentrations estimated by an enzyme immunoassay before and at 10 days after cows were treated with gonadotropin-releasing hormone. Cows having a progesterone concentration in skim milk less than 1.0 ng/ml were considered to have follicular cysts and those with concentrations of 1.0 ng/ml or higher were regarded as the cases of luteal cyst or cystic corpus luteum. Luteal cyst was characterized by progesterone values remaining high in the cows for 10 days after treatment, and cystic corpus luteum was characterized by a decrease in progesterone concentration after cows were treated. By the rectal palpation procedure it was impossible to differentiate luteal cyst and cystic corpus luteum from follicular cyst. The frequencies of follicular cyst, luteal cyst, and cystic corpus luteum were 65%, 19%, and 16%, respectively. Of 104 cows with follicular cysts as defined by milk progesterone assay result, 73 (70%) responded to the treatment with gonadotropin-releasing hormone, the milk progesterone concentration increasing from 0.7 +/- 0.2 ng/ml (mean +/- SD) to 1.8 +/- 1.1 ng/ml. The accuracy of rectal palpation 10 days after treatment for judgment of luteinization of follicular cyst confirmed by milk progesterone analysis was only 30% (48 cows of 160).  相似文献   

2.
Reproductive management programmes based on strategic use of prostaglandin F2 alpha (PGF2 alpha) to induce and synchronize oestrus in post-partum dairy cows are widespread. Repeated shortening of the oestrous cycle during early lactation in high-yielding dairy cows, however, could impair corpus luteum function and thus decrease fertility. The objective of this study was to analyse the effect of repeated treatments with the prostaglandin F2 alpha analogue D (+) cloprostenol sodium on progesterone concentrations indicative of a functional corpus luteum in post-partum dairy cows. Furthermore, the influence of milk production, parity and endometritis on progesterone concentrations under these circumstances were studied. Eighty-four cows of a commercial dairy operation were treated three to four times with D (+) cloprostenol sodium (Preloban; Hoechst Roussel Vet, Wiesbaden, Germany) at 14-day intervals, starting 22-28 days post-partum. Blood samples were collected prior to treatment 1 (sample 1) and 14 days after treatments 1, 2 and 3 (samples 2-4) and serum progesterone (P4) levels were determined. The percentage of cows with P4 levels < 1 ng/ml decreased from 51% in sample 1 to 23% in samples 3 and 4. More primiparous cows had low P4 levels 14 days after the second treatment than older cows (P < 0.05). Cows with low progesterone levels in sample 3 or 4 had lower protein contents in milk on the second milk test day post-partum and in their cumulative milk yield of the first 100 days of lactation. Clinical endometritis at post-partum examination did not influence progesterone levels after treatment with PGF2 alpha. Repeated application of PGF2 alpha (more than twice) in the post-partum period does not influence serum progesterone levels 14 days after treatment. Failure to develop luteal tissue after treatment contributed to the conception failures after first service.  相似文献   

3.
The objective of this study was to compare the concentrations of 17 beta-estradiol, progesterone, cAMP and cGMP in the follicular fluid of the largest cow follicle from the follicular phase of physiological sexual cycle and of follicles after synchronization of fut by cloprostenol (PGF2 alpha) and superovulation treatment with serum gonadotrophin (PMSG), in dependence on steroidal dominance of follicles. 2 x 25 cows, Slovak Pied x Lowland Black-Pied crossbreds with active corpus luteum, were subjected to superovulation treatment on the basis of rectal examination. Rut synchronization was achieved by cloprostenol of Czechoslovak provenience (Oestrophan Spofa), administered at the amount of 500 micrograms per dose. Serum gonadotrophin (Bioveta Concern, Ivanovice na Hané) at the amount of 2500 I. U. was administered forty-eight hours before the second dose of closprostenol. The animals were killed in slaughterhouses 48 hours later, or 72 hours later, since administration of the second dose of cloprostenol. The phase of the sexual cycle of control animals was determined by the method after Ireland et al. (1980) on the basis of morphological appearance of corpus luteum, presence of large preovulation follicle and by means of average concentrations of progesterone in blood serum. Aspirated follicular fluid was centrifuged using a cooling centrifuge at 3000 G. After separation, the supernatant was stored in a freezer at -18 degrees C until further treatment. 17 beta-estradiol and progesterone in the follicular fluid were determined by means of kits under the brand-names RIA-test-ESTRA (SI-125-9), or RIA-test-Prog (SI-125-6). Concentrations of cyclic nucleotides were determined by the RIA kits from the Institute vor Radioisotope Research, Production and Use (Prague), cAMP by 125J RIA kit (RIO12) and cGMP by 125J RIA (RIO42).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

4.
The effects of acetic acid administered at an amount of 300 to 600 g (5 to 10 mol) to the rumen of breeding cows, were investigated on ovulation, conception and progesterone levels in the blood and milk of cows with cloprostenol-induced (Oestrophan Spofa) oestrus at a dose of 500 micrograms i.m. In the group of 15 cows exposed to the acetic acid load five cows got in calf after the first insemination (33.3%), and 12 cows (80.0%) after all inseminations in 37.6 days after cloprostenol administration, with the insemination index 1.67 (Tab. I). In the control group (five cows) four cows (80.0%) got in calf after the first insemination, in total all five breeding cows got in calf in 20.6 days after cloprostenol administration, with the insemination index 1.2. In the experimental group of 15 cows a clinical examination of ovaries on day 7 after insemination revealed ovulation disorders in eight cows, that means in 53.3% of the animals (Tab. II). No ovulation disorders were observed in the control group of five cows. Progesterone levels in the blood showed high variability (Tab. III). In the group of cows administered acetic acid they were by more than a half lower (1.49; 0.67; 1.53 per ml) on days 7, 14 and 21 after insemination in comparison with the control group (3.35; 2.5; 3.38 ng per ml). The average progesterone levels in milk (Tab. IV) were 1.27 and 1.53 on day 7, 6.74 and 7.27 on day 14 and 3.52 and 11.85 ng per ml on day 21, respectively, the higher values apply to the control. It was not possible to evaluate reliably from the progesterone levels in the blood and milk if ovulation took place and if the corpus luteum was developing (Tab. V and VI). The clinical control of ovaries on days 7 and 8 after oestrus and insemination was more reliable to determine the ovulation disorders than the progesterone determination in the blood and milk of cows.  相似文献   

5.
The aim of the present study was to examine the plasma concentrations of progesterone, oestradiol-17beta and cortisol in the cows with cystic follicle and to examine its relationship with the ovulatory response to gonadotropin-releasing hormone (GnRH). Eighty-five post-partum Holstein-Friesian cows with cystic follicles regardless of the presence of corpus luteum were studied. Follicular size, presence of corpus luteum and occurrence of ovulation were checked by palpation per rectum. Blood collection and palpation per rectum were conducted on days 0, 7 and 14. Gonadotropin-releasing hormone was administered at day 7. Plasma concentrations of progesterone, oestradiol-17beta and cortisol were determined. Progesterone concentrations of <3.2, 3.2-4.8 and >4.8 nmol/l were defined as low, intermediate and high, respectively. Sixty-three (74.1%) of 85 cows showed low (<3.2 nmol/l =1 ng/ml) progesterone concentrations on day 0. Only 40 (47.1%) of them showed low-low pattern of progesterone at days 0 and 7. In 27 (31.8%) of them, progesterone concentration had increased by day 14. Of 22 cows having high progesterone concentration (>/=4.8 nmol/l) on day 0, corpus luteum was not detected in 18 cows (21.2%). Only in 10 cows, cystic follicle disappeared after GnRH administration. However, only one of 27 cows in which progesterone pattern was low-low-high at days 0, 7 and 14 experienced ovulation of the cystic follicle. Significantly lower oestradiol-17beta concentration was found on day 7 in cows showing a low-low-low pattern than a low-low-high pattern of progesterone (43.0 +/- 4.6 vs 55.8 +/- 2.8 pmol/l, p < 0.05). There was no significant difference in cortisol concentration on any days (days 0, 7 and 14) between cows showing a low-low-low and low-low-high pattern of progesterone. These results suggest that approximately one-fifth of cows diagnosed to have ovarian cysts possess luteal cysts and that a high oestradiol-17beta concentration at the time of GnRH administration is involved in the subsequent ovulation of the follicle, although ovulated follicle may not be cystic.  相似文献   

6.
Using rectal palpation and laparoscopy, the relationship of ovarian contents to plasma progesterone concentration during the oestrous cycle, early pregnancy and post partum periods in the swamp buffalo (Bubalus bubalis) was studied. During the oestrous cycle, four stages in the lifespan of the corpus luteum were seen laparoscopically. The mean (+/- sd) concentrations of progesterone in plasma in cows with and without a corpus luteum on their ovaries were 1.49 +/- 0.78 ng/ml (n = 31) and 0.14 +/- 0.09 ng/ml (n = 14), respectively. Plasma progesterone levels reflected age-dependent changes occurring in the cyclic corpus luteum. The accuracy of diagnosing ovarian contents was 82 and 91 per cent for rectal palpation and plasma progesterone levels respectively. Approximately 29 per cent follicles (larger than 10 mm) were incorrectly diagnosed as corpora lutea by rectal palpation.  相似文献   

7.
Actinomyces pyogenes from a case of endometritis was used to study the effects of infection of the bovine embryo between days 27 and 41 of pregnancy. From 10(9) to 10(10) washed organisms were introduced into the uterine lumen of four pregnant cows. Two pregnant cows were inoculated with sterile saline and four pregnant cows were treated with cloprostenol. Embryonic death and abortion followed 29 to 144 hours after the inoculation of the live bacteria. The aborted embryos were macerated or clearly degenerating and yielded profuse pure cultures of A pyogenes. Abortion was accompanied by a sustained increase in uterine tone, opening of the cervix, presence of vaginal pus and a vulval discharge and the persistence of the corpus luteum for at least eight days after abortion. Intrauterine inoculation with saline did not affect pregnancy, but embryonic death, abortion and regression of the corpus luteum occurred 66 to 72 hours after the treatment with cloprostenol. The results suggest that A pyogenes is a primary pathogen and is capable of causing embryonic death and abortion.  相似文献   

8.
A study aimed at validating a human progesterone enzyme immunoassay kit was carried out on cattle at Bambui, Cameroon. Progesterone ELISA Kits (EH-511) were obtained from Clinpro International. Forty-one cows were selected, of which 19 were pregnant and 22 within 14 days post partum. Blood samples were analysed and progesterone levels were deduced from a curve obtained from standard absorbance values (A 450). Results show that 95.5% of postpartum cows had progesterone levels below 1 ng/ml, with the highest level being 0.75 ng/ml. The mean level was 0.5 ± 0.26 ng/ml. The cows in the ‘pregnant group’ had progesterone levels ranging from 3.5 to 17.5 ng/ml. This kit can be used for measuring progesterone levels in cattle. Levels of 1 ng/ml for two consecutive samples or one sample at or above 3 ng/ml are an indication of the presence of corpus luteum, while cows below 1 ng/ml will be in anoestrus.  相似文献   

9.
本研究应用盐酸山莨菪碱(150mg)及微量的雌激素(4mg)对1~4胎90天以上未出现发情的不孕奶牛45例进行催情,其有效率为71.11%(32/45),其中卵巢静止为60%(15/25),持久黄体85%(17/20)。同时还发现用上述两种药物处理的10例患牛的血清孕酮含量在注射后的120小时以内均有程度不同的下降;当血清孕酮最低峰值<1.0ng/ml时,临床呈现发情征象的持久黄体牛为83.3%(5/6);卵巢静止牛为100%(4/4)。5例仅用微量雌激素(4mg)注射的患牛孕酮含量虽有变化但临床上均不出现显性发情症状。初步证明:盐酸山莨菪碱与微量雌激素协同可对奶牛有明显的催情作用,此方法迄今国内外未见报道。  相似文献   

10.
Four cows were inoculated into the uterus with Actinomyces pyogenes between 30 and 41 days of gestation. Gross morphological changes were monitored by rectal palpation and with a realtime B-mode two-dimensional scanner with a 7.5 MHz transrectal linear transducer, shortly before infection and afterwards at three to 12 hours intervals. Two control groups of cows 27 to 50 days pregnant were used: two cows were inoculated with 6 ml of sterile saline into the uterine lumen and four cows were treated with cloprostenol (prostaglandin F2 alpha analogue). There was a change in the uterine fluid from a black, non-echogenic image before infection to a grey or cloudy echogenic image as early as 21 hours after infection. There was an increase in the thickness of the endometrium of the horns and body of the uterus. The embryonic membranes thickened and separated from the endometrium as early as four hours after infection, followed by cessation of the embryonic heart beat, opening of the cervix and abortion. Abortion was followed by an increase in the amount of echogenic intrauterine fluid leading to an increase in the size of the uterus, and the cervix remained open for at least eight days. The area of the corpus luteum remained greater than 2 cm2 throughout the whole period. Intrauterine inoculation with sterile saline had no effects, but the administration of cloprostenol was followed by the death of the embryo and abortion within 72 hours, and the regression of the corpus luteum from greater than 2 cm2 at treatment to 0.4 cm2, 24 hours after abortion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
Two experiments were designed to test the hypothesis that induction of parturition in the cow would be more predictable with the simultaneous use of a combination of cloprostenol and dexamethasone than with either hormone used alone.

In experiment I all 19 beef cows treated with 500 μg cloprostenol and 25 mg dexamethasone in combination calved within 72 hours whereas dexamethasone (n = 19) or cloprostenol (n = 16) treatments alone each resulted in two induction failures. In those cows successfully induced, the mean interval from treatment to birth was 34.6 ± 1.4 hours for the cloprostenol plus dexamethasone group, 43.3 ± 2.4 hours for the dexamethasone group and 44.9 ± 2.1 hours for the cloprostenol group. Control cows (n = 15) did not calve during the first 72 hours after treatment with saline. The incidence of retained placenta ranged from 19 to 53% in induced groups whereas placentae were not retained by cows in the control group.

In experiment II all 30 beef cows in the cloprostenol plus dexamethasone group calved within the 72 hour limit, with a mean interval of 39.1 ± 1.0 hours. Twenty-six of 31 cows calved within 72 hours with a mean interval of 51.9 ± 3.4 hours after a single injection of cloprostenol and 29 of 33 cows calved within 72 hours with a mean interval of 52.6 ± 3.3 hours after two injections of cloprostenol, 12 hours apart. Five of 34 control cows calved within 72 hours of time of treatment. The incidence of retained placenta was again high in induced cows. Results indicate that the simultaneous administration of cloprostenol and dexamethasone does constitute a safe, reliable and effective method of inducing parturition in the cow.

  相似文献   

12.
The relative merits of three hormone treatments of dairy cows: (1) intravaginally administered progesterone and oestradiol benzoate; (2) intravaginally administered progesterone and injected cloprostenol; and (3) injected cloprostenol; begun 35-75 days after calving and designed to synchronize oestrus and ovulation and allow successful artificial insemination (AI) at fixed times, have been assessed utilizing information from progesterone concentrations in milk. From this it was concluded that 89% of the cows had ovulated one to three times between calving and the beginning of treatment. Treatment (2) was more effective than (1) in synchronizing ovulation. This was due to the fact that when treatments began early in the ovulation cycle, the requirement for a rapidly effective luteolytic agent was provided by cloprostenol but not by oestradiol benzoate. Treatment (2) was also more effective than (3) in synchronizing ovulation. This is interpreted as meaning that progesterone treatment for 12 days had a beneficial effect in restoring normal cyclic ovarian function in the cows after calving. Whilst cloprostenol administered alone did not have this beneficial effect, there is no evidence that it had a detrimental effect. Based on all cows in treatment groups, the proportion that became pregnant to the fixed-time AI was significantly greater after treatment (2) than after (1), but when based on numbers of cows with synchronized ovulation, there were no significant differences among treatments in the proportions becoming pregnant. The progesterone/cloprostenol treatment had a disadvantage in that when begun during the 11-22 day period of the ovulation cycle, so resulting in a long, total period of suppression of ovulation (mean, 32.1 days), fertility to the fixed-time AI was poor despite effective synchronization of ovulation. Ovulation cycles immediately following the failed, fixed-time AI were normal, both in length and in maximum, luteal-phase progesterone concentration and indicated normal corpus luteum function. Thus the infertility could be ascribed neither to poor timing of AI nor to gross degeneration of follicles prior to their synchronized ovulation following the prolonged suppression of ovulation. The 12-day progesterone treatments when given to anovulatory cows gave, within 5.5 h of their beginning, a concentration of progesterone in milk that was not significantly different from the maximum reached. This concentration declined during the 12 days of the treatment but remained above pretreatment level until 5.5 h after treatment withdrawal; the maximum reached was about half that in normal ovulation cycles.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

13.
本研究应用盐酸山莨菪碱(150mg)及微量的雌激素(4mg)对1~4胎90天以上未出现发情的不孕奶牛45例进行催情,其有效率为71.11%(32/45),其中卵巢静止为60%(15/25),持久黄体85%(17/20)。同时还发现用上述两种药物处理的10例患牛的血清孕酮含量在注射后的120小时以内均有程度不同的下降;当血清孕酮最低峰值<1.0ng/ml时临床呈现发情征象的持久黄体牛为83.3%(5/6);卵巢静止为100%(4/4)。5例仅用微量雌激素(4mg)注射的患牛孕酮含量虽有变化但临床上均不出现显性发情征状。初步证明:盐酸山莨菪与微量雌激素协同可对奶牛有明显的催情作用。  相似文献   

14.
The skim milk progesterone profile was assessed by radioimmunoassay, without extraction, from the day of insemination (day 0) until the cows were dried off on day 225 of gestation. A total of 418 samples were collected from 154 pregnant Holstein cows. The daily variation in skim milk progesterone was recorded from day 1 until day 45 of pregnancy to detect the commencement of progesterone secretion from the corpus luteum after insemination. Subsequent determinations were made every 2 weeks from day 46 until lactation ceased. On the day of artificial insemination and for the first 2 days after insemination, all the cows had a basal progesterone concentration <0.1 ng/ml. A rise in progesterone (0.2±0.1 ng/ml) was first detected on the third day after insemination. The progesterone values then increased significantly (p<0.001) until day 15.The values then remained nearly constant (2.5–3.5 ng/ml) until day 106 of pregnancy, when they began to decline. Between days 120 and 180 of gestation, progesterone was significantly decreased (2.2–2.9 ng/ml) before it rose again to the previous plateau (3.5–3.9 ng/ml) around day 180. The progesterone concentration then remained at the higher level until the animals were dried off.Abbreviations AI artificial insemination - RIA radioimmunoassay  相似文献   

15.
Progesterone was administered IM to 6 adult anestrous bitches at a dosage of 2 mg/kg of body weight. Serum progesterone concentrations were measured prior to progesterone administration and for 72 hours thereafter. The serum progesterone concentration time data were analyzed by use of a pharmacokinetics modeling computer program. The mean (+/- SD) peak serum progesterone concentration (34.3 +/- 7.8 ng/ml) was reached at 1.8 +/- 0.2 hours after progesterone administration. The mean serum progesterone concentration was 6.9 +/- 1.4 ng/ml at 24 hours and 2.0 +/- 0.4 ng/ml at 48 hours after progesterone administration. By 72 hours after administration, mean serum progesterone concentration was 0.9 +/- 0.2 ng/ml, which was comparable to serum progesterone concentrations prior to injection. The mean half-life of the absorption phase was 0.5 hours (range, 0.3 to 0.7 hours). The mean half-life of elimination was 12.1 hours (range, 9.5 to 13.8 hours). By analysis of the data, it was established that a dosage of 3 mg/kg, when the hormone was given IM to dogs once a day, would maintain serum progesterone concentration greater than 10 ng/ml.  相似文献   

16.
Two hundred and fifty-one cows fresh at least 37 days with normal reproductive tracts and palpable ovarian structures which clinicians believed to be corpora lutea and which were presumed to be producing progesterone were treated with 500 micrograms of cloprostenol. The cows were stratified into three groups based on milk progesterone concentrations in whole milk samples taken at the time of examination. The low group had milk progesterone concentrations less than or equal to 1 ng/ml, the intermediate group had milk progesterone concentrations between 1 and 3 ng/ml, and the high group had milk progesterone concentrations greater than or equal to 3 ng/ml. The proportion of cows in each group inseminated within 5 days of treatment and the fertility at that breeding were compared. There were no significant differences among the groups with respect to the proportion of cows that came into estrus within 5 days. However, the conception rate of the high group (54%) was significantly greater than that of the intermediate group (26%). To study the relationship between practitioner experience and diagnostic accuracy the proportion of cows with low, intermediate and high concentrations of progesterone selected by clinicians with more than 3 years experience was compared to that for clinicians with 3 years of experience or less. Less experienced clinicians were significantly more likely to make a false positive diagnosis of functional luteal tissue in cows with palpable ovarian structures than were more experienced clinicians.  相似文献   

17.
To determine the effect of the hyperadrenal state on corpus luteum (CL) function, we treated intact and adrenalectomized (ADRX) heifers with adrenocorticotropin (ACTH) and hydrocortisone. ACTH treatment of intact heifers by infusion of 1 mg alpha 1-24 ACTH/24 hr from day 2 to 25 of an estrous cycle increased progesterone concentrations in plasma to 4 +/- .52 ng/ml plasma on days 3 to 4. Thereafter, progesterone concentrations declined, indicating severe suppression of CL function as compared to that of control heifers. Similar infusions of ACTH to ADRX heifers did not alter CL function as reflected by progesterone concentrations in jugular plasma. Infusion of ADRX animals with hydrocortisone succinate (100 mg/24 hr) decreased progesterone in plasma during the cycle, with maximum values averaging less than 4 ng/ml, compared to concentrations of 6 to 7 ng/ml in control ADRX heifers. Chronic administration of ACTH or hydrocortisone to heifers caused a decreased progesterone secretion during the luteal phase of the estrous cycle. On the basis of these results, we suggest that stress, as indicated by the hyperadrenal state, could inhibit progesterone secretion by the corpus luteum.  相似文献   

18.
A short calving to conception interval is of main importance to achieve high economic efficiency in dairy cow industry. In order to reduce this interval, several hormonal treatments have been put on the market, in which cloprostenol, a synthetic analogue of prostaglandin F2alpha (PGF2alpha). The aim of this study was to compare fertility of cloprostenol-induced oestrus to that of spontaneous oestrus in dairy cows. In a group of 525 cows, 280 (treated group) were administered 0.5 mg cloprostenol i.m. after transrectal corpus luteum (CL) detection, and inseminated at detected oestrus during the following week. The other 245 cows (control group) were inseminated during spontaneous oestrus. Whey progesterone concentrations were checked at treatment and at insemination in order to remove from the study cows whose P4 levels indicate a non-functional CL, or a lack of luteolysis respectively. Moreover, cows that were not inseminated due to genital problems were also excluded from this study. Conception (59% vs 54.5%) and calving rates (93.7% vs 93%) were not significantly different between the two groups.  相似文献   

19.
The objective of the study was to check a contingent negative effect of repeated treatment of heifers by PGF2 alpha--Oestrophan (SPOFA)--on the course and quality of their ovarian activity and external heat signs. Changes in progesterone concentrations were evaluated three times a week. Three heifers were subjected to treatment eight times and two heifers nine times. Of 42 applications of Oestrophan (SPOFA) the response was positive in 95.2% (forty heats). When Oestrophan (SPOFA) was administered on the fourth and sixth day of the sexual cycle, in two cases no heat nor luteolysis of corpus luteum was detected; this was demonstrated by hormonal investigation. Of the forty evaluated heats, 82.5% were classified as strongly and medium expressive, the remaining were weakly expressive. The onset of heat was found to be on the average 72.6 hours after Oestrophan (SPOFA) administration, in 9.1% of the cases the heat started about 48 hours after administration, 12.4% of cows showed the heat signs between 72nd and 96th hours.  相似文献   

20.
This study analyses anomalous cases of gestation ending in pregnancy loss during the early foetal period and their effect on progesterone and plasma pregnancy-associated glycoprotein-1 (PAG-1) concentrations. Data derived from a large-scale ultrasound pregnancy diagnosis programme in high producing dairy cows. Over a 3-year period (2004–2007), a very low incidence (0.5%: 15 of 3094) of anomalous pregnancies was recorded. The results revealed that the following anomalies were detected on days 35–41 of gestation in cows carrying singletons with one single corpus luteum: embryo death in eight cows (0.3%); and embryo in the uterine horn contralateral to the corpus luteum in seven cows (0.2%). All these animals suffered pregnancy loss during the early foetal period. In cows carrying dead embryos, no signs of conceptus degeneration were observed on pregnancy diagnosis. Amnion size (approximately 25 mm diameter) and uterine horn fluid contents were estimated to be similar to those of the normal pregnant cows in this period. In the contralateral gestations, live embryos were observed in all ultrasound checks before pregnancy loss. Uterine fluid contents increased in the two cows in which gestation continued for more than a week. In the cases of embryo death but not in those of contralateral gestation, a drop in PAG-1 levels was noted prior to pregnancy loss. Two cows carrying dead embryos increased with time allantoic fluid contents. The PAG-1 values increased with time in one cow bearing a dead embryo (from 2.31 to 6.79 ng/ml) and in two of the contralateral gestations (from 1.66 to 2.33 ng/ml and from 0.39 to 6.79 ng/ml, respectively). Results of this study indicate that the foetal membranes continue to undergo some activity following embryo death, and that contralateral pregnancy may determine failure of the gestation process.  相似文献   

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