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1.
Contents: The morphological appearance of ovarian structures in 79 sows with ovarian cysts was examined. Sixty sows had been culled due to sterility; 19 sows had been repeatedly investigated clinically before slaughter. It was found that cystic ovaries without corpora lutea (CL) had the largest diameter and volume (151.3 cm3), in comparison to both cystic ovaries with CL (85.7 cm3) and normalovaries (16.9 cm3). The number of cysts on ovaries without corpora lutea was approximately twice as high as on the ovaries with CL (23.3 vs 12.1 cystslsow; p < 0.001). A combined form of degeneration consisting of large (> 1.5 cm in diameter) and small (1.5 em in diameter) cysts was found in 63% of the animals, whereas degeneration with only small cysts occured in 8% of the cases. Dark CL, interpreted as being functional, were mainly present in animals with up to 10 cysts per sow (24 out of 27 sows, p < 0.001); pale CL, interpreted as being weakly functional, were mainly found on ovaries with more than 10 cysts (19 out of 23 sows; p < 0.001). Based on macroscopical differentiation cyclic activity was found to be dependent to the number of cysts. Regular or irregular estrous cycles were observed in oligocystic animals (10 cysts/animal) with functional CL (58%). Up to 75% of the animals with pale or absent CL showed no estrous activity.  相似文献   

2.
Estimation of superovulation response in donor cows   总被引:1,自引:0,他引:1  
Estimates were made of the superovulation response in donor cows using ovarian size, the number of corpora lutea (palpated per rectum) and blood progesterone levels. Neither the estimated number of corpora lutea nor ovarian size gave a satisfactory prediction of superovulation response. There was a large discrepancy between the number of corpora lutea present on the ovaries of nine superovulated cows (166) and the estimated number (106). All the corpora lutea on superovulated ovaries were smaller than normal (1.95 g). Blood progesterone levels at the time of embryo recovery were correlated with both the number of corpora lutea on the superovulated ovaries (r = 0.9, P less than 0.001) and the weight of the corpora lutea (r = 0.95, P less than 0.001). There were 67 embryos and ova recovered from the nine donors, representing 40 per cent of the actual and 63 per cent of the palpated corpora lutea. However, neither ovarian size, the number of corpora lutea nor blood progesterone levels were correlated with embryo production.  相似文献   

3.
The results of continually repeated transrectal palpations, performed in 168 post partum periods, 383 estrous cycles and 178 early pregnancies, were used to describe and to discuss the left-right distribution of ovarian functional structures. In cycling as well as in pregnant cattle, anovulatory interestral follicles and estrous follicles or corpora lutea in the mean were all distributed at 41% and 59% on the left and right ovaries respectively. No signs were found indicating that the position of functional structures would be influenced by local interactions between follicles and corpora lutea. At least for cyclic ovarian activity, and in early pregnancy, the interrelationship observed between the locations of these structures could be put down to the normally increased activity of the right ovary. After delivery, the first follicles preferentially became discernible on the ovary opposite to the previously pregnant uterine horn. But, as from the 4th follicle p.p. onward, the distribution of new ovarian structures again agreed with the one of the ensuing reproductive stages. After calving, probably the position of new follicles is temporally influenced by direct signals from the uterine horns affected differently by pregnancy. Several observations indicate that the factors causing asymmetrical ovarian activity could exert a selective effect on the recruitment of the dominant and solitary interestral follicles from the pool of their minor and less differentiated precursors.  相似文献   

4.
The ovaries of 59 pluriparous cows of unknown reproductive history were palpated, scanned and dissected on the day of slaughter to compare the accuracy of rectal palpation and transvaginal ultrasonography with a 5 MHz linear array for the detection of corpora lutea and follicles. The rectal palpation was first carried out to judge the presence of follicles of more than 5 mm diameter, and corpora lutea which were classified as young (days 1 to 4), mid-cycle (days 5 to 16) or old (days 17 to 21) according to morphological criteria. The cows were then examined for follicles and corpora lutea by ultrasonography and the corpora lutea were again classified directly as young, mid-cycle or old according to their appearance. The cows were then slaughtered, their ovaries dissected, and the follicles over 5 mm in diameter were counted and the corpora lutea were classified in the above mentioned age categories. For the detection of a mid-cycle corpus luteum the sensitivity and predictive value of rectal palpation were, respectively, 83.3 per cent and 73.2 per cent and for ultrasonography the sensitivity and predictive value were 80.6 per cent and 85.3 per cent, respectively. However, both techniques were inaccurate for the detection of young and old corpora lutea. For detecting follicles ultrasonography was a significantly better method than rectal palpation. Ultrasonography detected 95 per cent of follicles larger than 10 mm whereas rectal palpation detected only 71 per cent of these follicles. Both techniques failed with follicles 5 to 10 mm in diameter; only 21.5 per cent were detected by rectal palpation and 34.3 per cent by ultrasonography.  相似文献   

5.
Anovulatory haemorrhagic follicles (AHFs) are often the reason for ovulation failure in the mare. As the underlying factors that lead to AHF development are not well understood, it was of interest to investigate the vascularization of AHFs compared with normal follicles and corpora lutea (controls). In the present study, the ovarian cell populations investigated immunohistochemically included granulosa and luteal cells as well as various vascular structures. None of these cell types showed differences in the expression of vascular endothelial growth factor A (VEGF-A) between control ovaries containing normal follicles and corpora lutea and ovaries with AHFs. In contrast, a considerable reduction in the proportion of Flk-1-expressing cells, together with a decreased intensity of staining, was apparent in the AHFs. This greatly reduced expression of Flk-1 in the luteinized cells and the vascular structures of AHFs may lead to a distinct decrease in the potential pro-angiogenic activity of VEGF-A in these structures compared with the situation in normal follicles and corpora lutea. Furthermore, the authors suspect that the distinct expression of angiopoietin2 and VEGF-A seen in the cells within the inner fibrous layers of the AHFs was caused by hypoxia resulting from deficient vascularization, as suggested by the irregularity of the capillaries present in the luteinized wall of the AHF. In addition, whereas LH-receptor (LH-R) expression occurred uniformly in all stages of development of the corpora lutea in normal control ovaries, there was highly variable labelling for LH-R in all the AHFs examined, thereby indicating a possible numerical deficiency of LH-receptors in AHFs. The authors concluded that, despite the apparent expression of sufficient VEGF-A in the AHFs allows ovulation and corpus luteum formation, a relative lack of receptor, Flk-1, effects the pro-angiogenic activity of VEGF-A which could be a reason for ovulation failure associated with AHF formation.  相似文献   

6.
Our objectives were to determine whether or not ovarian follicles contribute to spontaneous luteal regression in heifers and, if so, when during diestrus do follicles exert their effect. Thirty-one Holstein heifers having displayed at least one estrous cycle (19 to 21 d) were assigned, as available, to randomized blocks for a factorial experiment. Reproductive organs were exposed through a midventral incision on d 9, 12 or 15 postestrus (estrus = d 0). Visible follicles were electrocauterized and both ovaries were x-irradiated (1,500 rads) in treated heifers, whereas ovaries of controls were exteriorized but follicles were not destroyed and ovaries were not x-irradiated. In two additional heifers, the ovary containing the corpus luteum was exteriorized and x-irradiated on d 15 postestrus, but follicles were not electrocauterized. Jugular blood was collected before and every 8 h after surgery until d 24 postestrus. All heifers were ovariectomized on d 24 postestrus to inventory follicles and to weigh corpora lutea. No follicles (greater than or equal to 1 mm diameter) were observed in ovaries from treated animals and concentrations of estradiol-17 beta did not change over time, whereas different numbers of follicles were observed in ovaries from controls and concentrations of estradiol-17 beta increased (P less than .05) during proestrus. Hence, treatment destroyed follicles and prevented follicular development. On d 24 postestrus, corpora lutea from treated heifers (5.5 +/- .5 g) were heavier (P less than .001) than corpora lutea from controls (1.1 +/- .1 g), independent of day when follicles were destroyed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
A study was conducted to evaluate the effects of maternal undernutrition on the hypothalamic–pituitary–gonadal axis in female sheep offspring. Pregnant ewes were fed to 100% throughout pregnancy (Control) or to 50% from 0 to 30 (R1) or from 31 to 100 days of gestation (R2). Female lambs were selected and fed to appetite throughout the study. At 2, 5.5 and 10 months of age a GnRH challenge was conducted. At the age of 10 months lambs were synchronized and blood samples were collected at 3 h intervals for 72 h following sponge removal. At slaughter (10 months) ovaries were removed and examined macroscopically. Maternal undernutrition did not affect the time of the onset of puberty, defined as the first increase in plasma progesterone concentrations ≥1 ng/ml. The magnitude of the pre-ovulatory gonadotrophin surge and the time to surge were unaffected by treatment. The LH and FSH response to GnRH challenge did not differ between groups at 2 and 5.5 months but at 10 months of age a higher (p < 0.05) FSH response was found in R1 group. Although the total number of visible follicles and corpora lutea did not differ between groups, a significant higher (p < 0.05) number of small (2–3 mm diameter) follicles in R1 group and a significant lower number (p < 0.05) of corpora lutea with diameter 8–11 mm and not even one with diameter >12 mm were detected in the ovaries of R2 lambs. In conclusion, maternal undernutrition during the first month of pregnancy resulted in increased pituitary sensitivity to GnRH and increased number of small follicles in the ovary, while during mid to late gestation resulted in a reduction of large corpora lutea in female offspring.  相似文献   

8.
The purpose of this experiment was to determine the ovulation rate after treatment with human chorionic gonadotropin (hCG) in two groups of gilts characterized by different ovarian morphology: grape-type (GT; n = 11) and honeycomb-type (HT; n = 7). At 170 d of age (d 0), gilts were examined by laparoscopy and ovarian type was determined by the distribution of macroscopic follicles present on the ovarian surface. Five to ten minutes after surgery, each gilt received a single injection (i.m.) of 750 IU of hCG. At d 0, GT ovaries had a greater number of large follicles (greater than or equal to 6 mm) than HT ovaries (10.0 +/- .5 vs 2.6 +/- .3; P less than .05), whereas HT ovaries had more small follicles (1 to 3 mm; HT: 42.3 +/- .8 vs GT: 26.7 +/- .9; P less than .05) and total follicles (HT: 59.4 +/- 2.3 vs GT: 52.2 +/- 1.5; P less than .05), although numbers of medium follicles (4 to 5 mm) were similar (GT: 15.6 +/- .8 vs HT: 14.6 +/- 1.7; P greater than .10). Number of induced corpora lutea (CL) per ovary was greater (P less than .05) in gilts with GT ovaries (10.59 +/- 2.9 CL) than in gilts with HT ovaries (5.21 +/- .66 CL). Total weight of luteal tissue (LT) per ovary and serum progesterone concentrations 8 d after induction of ovulation were greater in GT gilts than in HT gilts (GT: 6.37 +/- 1.09 g vs HT: 3.31 +/- .49 g for LT, P less than .05; GT: 21.08 +/- 4.76 ng/ml vs HT: 13.40 +/- 2.05 ng/ml for progesterone, P less than .07).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

9.
The present study was designed to examine the influence of gonadotrophins treatment on the ovarian morphology changes and plasma concentrations of steroid hormones in peripheral blood. The experiment was performed on sexually pubertal gilts (Large White x Landrace) of similar age (7-8 months) and body mass (100-110 kg) with two controlled subsequent estrous cycles. The animals were randomly divided into four groups: two control consisting of pigs with the luteal phase (n = 9, the 10th day of the estrous cycle) and the follicular phase (n = 6, the 20th day of the estrous cycle) and two experimental ones consisting of animals with both mentioned periods (n = 7 and n = 9) treated with gonadotrophins (PMSG and hCG). The gilts in the luteal phase were injected (s.c.) with gonadotrophins at a daily dose of PMSG 400 and hCG 200 IU from the 16th to the 27th day (the 6th day of the next estrous cycle). The gilts in the follicular phase, were injected with the same dose of gonadotrophins but from the 8th to the 19th day of the estrous cycle. Plasma concentrations of P4, A4, T, E1, E2 and metabolite of PGF2 alpha-PGFM were determined by radioimmunoassay (RIA) method. Injections of PMSG and hCG in both experimental groups produced several times enlarged: weight, size and volume of ovaries and alterations in a number of structural elements as compared with those found in the control animals. The morphological elements presented in ovaries: corpora haemorrhagica, corpora lutea, regular and atretic follicles and first of all cysts by distinctly differentiation thickness of the walls are characteristic for cystic ovarian degeneration. Plasma concentrations all determined hormones after gonadotrophins treatment in experimental groups were increased except E1 (insignificant decrease) in luteal phase as compared with those found in the control groups. Statistically significant increase (p < 0.001) in plasma concentrations of P4, A4, and T in both experimental groups and E2 (p < 0.001) in luteal phase were noted. In peripheral plasma concentrations increase of E1 and E2 in follicular phase of the estrous cycle were insignificant.  相似文献   

10.
Experiments were conducted to examine the cellular localization of inhibin alpha-subunit, protein kinase B (PKB/Akt), and FoxO3a proteins in the ovaries of minipigs, Chinese Xiang pigs, by immunohistochemistry. The results indicated that inhibin alpha-subunits were localized in the granulosa cells of follicles at all stages but were not localized in corpora lutea. PKB was localized in the granulosa cells of primordial follicles and in the basal layers of the granulosa cells of preantral and antral follicles, but were not localized in atretic follicles and corpora lutea. FoxO3a was localized in the granulosa cells of follicles at all stages and was extensively localized in the cytoplasma of the luteinized granulosa cells of corpora lutea. Together, the stage- and cell-specific expression patterns of inhibin alpha-subunit, FoxO3a, and PKB suggest that these proteins might play potential roles in follicular development, atresia, and luteinization in the minipig.  相似文献   

11.
The objective of this study was to assess the efficacy of two reduced doses vs a high/luteolytic dose of cloprostenol on luteolytic activity and synchronization of oestrus in cyclic goats. Experiment 1, included 24 goats randomly allocated to three groups: control group (group H) received a single high dose of cloprostenol (87.5 μg; 1.0 ml; i.m.) and M and L groups, which received half (43.75 μg; 0.5 ml) and a third (26.25 μg; 0.3 ml) of the highest dose, respectively. Experiment 2, included 24 goats randomly assigned to the same experimental groups. Each group was treated using two injections of cloprostenol administered 10 days apart to synchronize oestrus. Transrectal ultrasonographic scanning (US) was performed to detect the presence, size and development of corpora lutea and ovarian follicles. Furthermore, detection of oestrus was performed every 12 h between 24 and 72 h after the second injection of cloprostenol, and the luteolytic effect was verified by US. In Experiment 1, all goats that had corpora lutea at timing of treatment regressed their corpora lutea. In Experiment 2, the occurrence of oestrus and the interval between treatment to onset of oestrus were: 100%, 49.5 ± 3.0 h; 100%, 51.0 ± 3.0 h; and 75%, 56.0 ± 3.5 h for H, M and L groups, respectively. The development of preovulatory follicles and occurrence of subsequent corpora lutea were similar among groups. In summary, the use of 26.25 μg of cloprostenol is effective for the synchronization of oestrus in cyclic goats.  相似文献   

12.
We examined the response to exogenous prostaglandin F2α in cattle with or without palpable structures believed to be ovarian follicles. All animals had ovarian structures diagnosed by palpation as corpora lutea. The cows were placed into two groups: those with follicles which were estimated by the palpators to be ≤13 mm diameter (n=60); and cows with no palpable follicles or with follicles <13 mm diameter (n=133). Comparisons of proportion in estrus within five days, days to estrus, and milk progesterone levels failed to show significant differences between the groups.  相似文献   

13.
14.
The PMSG-superovulatory response was determined by ovarian dissection in 20 cows and compared with estimates made by laparoscopy laparotomy and rectal palpation at day 7 of the induced estrus. The corpora lutea count made transrectally seriously underestimated real corpora lutea numbers when more than nine corpora lutea were present. Rectal palpation failed to correctly identify the number of follicles ≥ 10 mm when more than four follicles were present. After ovarian dissection, laparotomy was the most constant and accurate method to obtain the number of ovulations, followed by laparoscopy. The excessive weight and the large size of the ovaries associated with the presence of large unovulated luteinized follicles were often responsible for the erroneous estimates of the ovulation rate by rectal palpation.  相似文献   

15.
In females, follicle‐stimulating hormone (FSH) targets a FSH receptor (FSHR) expressed only on granulose cells, inducing maturation of the ovarian follicles. We hypothesized that genetic variants in the FSHR gene influence litter size by affecting the number of corpora lutea. We fine‐mapped a region of Sus Scrofa chromosome 3 that contains quantitative trait loci for corpora lutea. Polymorphisms were detected in the exons and 5′ flanking region of the porcine FSHR gene, a positional candidate for the statistically most significant of the quantitative trait loci. Finally, 248 F2 animals from a Duroc and Meishan cross were genotyped for three FSHR SNPs at positions 74, 532 and 1166, and these were correlated with the phenotypes of litter size and corpus luteum number. Three haplotypes were identified: M1 (G/G/C), M2 (C/A/T) and D (C/A/C). In the F2 population, the M1 haplotype was associated with a greater number of corpora lutea (P < 0.01) and also seemed to be associated with increased litter size, although the association was not significant (P = 0.2571). Some polymorphisms resulting in amino acid substitutions in these genes were excluded from the polymorphisms possibly responsible for the number of corpora lutea.  相似文献   

16.
A possibility was investigated of using heifers prepared for embryo reception by i. m. double application of Oestrophan (Spofa) luteolytic preparation. After a clinical examination of ovaries and corpus luteum, out of the total number of 2894 animals synchronized for nonsurgical ipsilateral transfer in the D7 stage only 2038 (70.4%) recipients were used. Almost 30% (856) heifers were discarded from the role of recipients, mostly due to the functional disorders of the cyclic activity of ovaries manifesting themselves as luteal cysts (22.5%), cysts of corpus luteum (16.5%), small or young corpora lutea (12.7%), postovulation states (4.5%), and also as a high frequency of the follicular activity without the presence of corpus luteum (37.9%). The occurrence of follicular cysts (1.4%) and nonfunctional ovaries (2.8%) was considerably lower. The high number of discarded recipients which results, in the complex of causes, from qualitative nutritional disorders, husbandry and zoo-hygienic shortcomings and stress-inducing factors in the course of recipient selection and preparation, diminishes the transfer efficiency and considerably increases the claims for the numbers of recipient prepared for ovulation. In the conditions of our workplace where 10.6 to 12.8 transferable embryos are recorded from one successful superovulation and their survival is 65 to 68.6%, it will be necessary, at the present level of recipient discarding, to prepare 13.8 to 16.6 heifers per donor to make full use of the superovulation effect.  相似文献   

17.
Laurincik, J., L. Kolodzieyski, V. Elias, P. Hyttel, Y. Osawa, A. Sirotkin: Immunocytochemical localization of aromatase in the ovary of superovulated cattle, pigs and sheep. Acta vet. scand. 1994, 35, 185-191.–The localization of aromatase, an enzyme converting androgens to estrogen, in the ovaries of superovulated cattle, pigs and sheep was studied immunocytochemically in the preovulatory and postovulatory period using anti-human placental aromatase cytochrome P-450 antiserum. Immunostaining for aromatase was detected in the granulosa cells of preovulatory follicles of all species studied. Theca interna cells were stained in preovulatory follicles in the pig but not in cattle and sheep. Interstitial gland cells, cumulus cells and oocytes were unstained in all species. In cattle and pig the corpora lutea were unstained whereas they displayed staining in the sheep. Preantral and small antral follicles were unstained during both the preovulatory and postovulatory period in all species.It is concluded that granulosa cells of preovulatory follicles are the main residence for aromatase activity in superovulated cattle, pig and sheep, whereas the activity of theca interna and corpora lutea is species specific.  相似文献   

18.
In the present study oestrogen receptor alpha(ERalpha) and oestrogen receptor beta (ERbeta) mRNA were localized in various ovarian cell types of 23 cows at different stages of the oestrous cycle. ERalpha was detected by immunohistochemistry and the localization of ERbeta mRNA was examined using in situ hybridization. The immunostaining of ERalpha was low in the ovarian follicles, tunica albuginea and surface epithelium, but high in cells of the deep stroma and superficial stroma, which indicates a functional role of ERalpha in the cells surrounding the follicles. In contrast, ERbeta mRNA scores were low to moderate in primordial and primary follicles, and increased with the development of the follicle. ERbeta mRNA scores were higher in cystic follicles than in obliterative follicles. In the corpora lutea and corpora albicantia the scores for ERbeta mRNA were moderate. Furthermore, in the corpora lutea, ERbeta mRNA levels showed cyclic variations and were low during early dioestrus. The correlation between plasma progesterone levels and the score for ER was low and negative in all ovarian cell types. This study demonstrates the predominant role of ERbeta over ERalpha in bovine ovarian structures. Furthermore, the colocalization of both ERbeta mRNA and ERalpha in most cell types suggests possible interactions between both ER subtypes.  相似文献   

19.
Contents: The content of progesterone, estradiol-17β, and testosterone of plasma and cystic fluid was determined in 79 sows with ovarian cysts. The average progesterone concentration of sows with dark corpora lutea (CL) was higher than of sows with pale or absent CL (39.4 vs. 8.7 vs. 8.0 ng/ml plasma; p < 0.001; and 7512 vs. 3644 vs. 2723 ng/ml cystic fluid, respectively; p < 0.001). The cystic fluid of animals with oligocystic ovaries (10 cystslanimal) had a significant higher progesterone concentration in comparison to potycystic animals (7200 vs. 3682 ng/ml; p < 0.001). Testosterone and estradwl-17β levels in plasma and in cystic fluid of polycystic animals were significantly higher in comparison to oligocystic animals (Plasma-Testosterone: p < 0.01; Plasma-Estradwl: p < 0.05; Cyst-Testosterone: p < 0.01; Cyst-Estradiol: p < 0.001). In oligocystic ovaries testosterone in cysts exceeded the estradiol-17β levels, whereas in polycystic ovaries the situation was vice versa (p < 0.001).
It is suggested that cystic ovarian degeneration in the sow is not exclusively a gradually progressing process, rather then a complex syndrome with three components, were characterized by a separate course of development (oligocystic, polycystic. oligo-polycystic syndrome).  相似文献   

20.
In this study diagnostic certainty of ultrasonography and rectal palpation concerning the detection of follicles and C.I. was compared by evaluation of the findings obtained with ultrasonography in waterbath and dissection of the ovaries after slaughter. Clinical examinations were performed on a total of 30 cows (transrectally and ultrasonographically, 5.0 mhz, linear) in slaughterhouse. In the laboratory ovaries were evaluated after slaughter both macroscopically and by ultrasonography in waterbath. Diagnostic reliabilities of these methods were compared. No difference between the methods was determined concerning the longitudinal measurements of corpora lutea (19.96 +/- 4.83 mm, 20.41 +/- 5.41 mm, 21.45 +/- 5.26 mm by ultrasonography, waterbath and macroscopy respectively). By means of determining the correct identification of corpora lutea, the error rate was 24.1% and 17.2% for rectal palpation and ultrasonography respectively. The comparison of rectal palpation and macroscopy showed that three small corpora lutea and two corpora lutea with small cavity were determined wrongly as small follicles and two corpora lutea were determined whereas they were not present actually. With ultrasonography four small C.I. could not be detected and one C.I. with cavity was wrongly determined as follicle. It was noticed that follicles bigger than 10 mm (F2 = 10-15 mm, F3 = 16-20 mm) could be determined more accurately by means of ultrasonography than by rectal palpation (with ultrasonography: F2 = 90.48%, F3 = 100.0%; with rectal palpation, F2 = 61.9%, F3 = 200.0%). The correlation of the findings of rectal palpation or ultrasonography and blood progesterone levels was 86.2% and 89.7% respectively. This accordance was 96.6% for progesterone levels and waterbath and macroscopic findings.  相似文献   

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