A 14-year-old, 530-kg, multiparous, pregnant Quarter Horse mare was referred for evaluation of premature mammary gland development and lactation. The mare was in the seventh month of gestation. The mare had a history of subfertility and was receiving weekly injections of long-acting progesterone, prescribed by the referring veterinarian. The last dose had been administered four days before presentation. Upon presentation, the mare had vital signs within normal limits, a moderately developed, nonpainful udder with galactorrhea, and no vulvar discharge. Transrectal palpation revealed a well-toned uterus and cervix and discreetly palpable fetal parts, however, ballottement of the fetus did not result in appreciable fetal movement. Transrectal ultrasound was unremarkable, but transabdominal ultrasound revealed one underdeveloped, immotile fetus in the left uterine horn with no heartbeat. Abortion was induced with repeated doses of cloprostenol. Fifty-four hours after the first cloprostenol injection, the mare displayed signs of labor, the cervix was manually dilated, and the fetus and fetal membranes were expelled with gentle manual manipulation. Standard postabortion care included uterine lavage and oxytocin for 48 hours before being discharged to the care of her owners. Fetal crown-rump length (53 cm) was consistent with a 6-month fetus rather than its gestational age of 7 months. The umbilical cord was edematous, and a distended, fluid-filled structure surrounded the cord at the intersection of the allantoic and amniotic segments of the umbilical cord. This structure was determined to be the severely dilated urachus. Microscopic findings included placental stromal mineralization, distended umbilicus adventitia, and dilated umbilical lymphatics with no other significant findings. Remaining abortion diagnostic tests were unremarkable. The mare recovered well and was discharged to the care of her owner two days after abortion. The following breeding season the mare carried a healthy foal to term.

Four crossbred cows with mummified fetus were utilized for the study. The cows were subjected to gynecological examination and based on the findings the cases were diagnosed as mummified fetus. The cows were treated with 2 mg estradiol valerate and 500 µg cloprostenol and were examined every 12 hr after 24 hr of the treatment for cervical dilatation and other signs related to fetal expulsion. The time duration between treatment and starting of cervical dilatation ranged from 48 to 58h (53.00 ± 2.08 hr). Complete dilatation of cervix was observed after 70.00 ± 2.94 hr post treatment (Range = 64-76 hr). The mean fetal crown-rump length (CRL) was 31.5 cm, which ranged from 27.5 to 38 cm. The number of cotyledons in pregnant horn also showed wide variation (Range 24-38 numbers) with mean ± SE of 30.3 ± 3.07 numbers. In the placenta of three animals irregular shaped large adventitious cotyledons were observed in the inter-cotyledonary areas. Out of the four animals treated, three animals were conceived within three estrous cycles and one animal had cystic ovary in the next cycle and was not conceived even after four cycles. It was concluded that the estradiol and prostaglandin F2α (PGF2α) combination therapy was effective for expulsion of mummified fetus in crossbred cows without affecting much on future fertility.

Suisynchron premix and oestrophane were tested through 6 generations of laboratory mice for their action on fertility (litter parameters). No fertility-reducing effect was recordable.

A total of thirty water buffalo cows aged 3 to 8 years were treated for superovulation over the July-October period. Nine of the animals were injected with FSH at the rate of 40 mg at 12-hour intervals in the course of 4 consecutive days, and the remaining 21 animals were injected with 3,000 IU gestyl in the middle of the luteal phase. Forty-eight hours after stimulation started both groups were treated with 500 micrograms cloprostenol. Five out of the 9 buffalo cows (55.5 per cent) of group I and 15 out of 12 buffalo cows (71.4 per cent) of group II manifested estrus at an average interval of 44.4 +/- 3.6 and 40.5 +/- 3.29 hours, respectively, following the application of cloprostenol. The superovulatory treatment of the animals of the two groups led to average values of 5.6 +/- 1.89 and 4.0 +/- 0.98 corpora lutea and 1.0 +/- 0.63 and 2.7 +/- 1.41 follicules larger than 8 mm; 2.6 +/- 1.60 and 2.1 +/- 0.94 embryos of high quality were obtained through the use of a nonsurgical method of flushing.

Brazil has presented tremendous progress in non-surgical embryo transfer (NSET) in sheep and goats. New instruments and techniques for non-surgical embryo recovery (NSER) and NSET in small ruminants were implemented. Recent improvements include refinement of the protocols for cervical relaxation combining oestradiol-oxytocin-cloprostenol treatment at specific times before NSER in sheep; recipient goats do not require any hormonal drugs to induce cervical dilation and direct embryo transfer by the cervical route yields excellent results. Transrectal ovarian ultrasonography (B-mode but especially colour Doppler) have proven to be accurate methods to localise and enumerate corpora lutea and luteinised unovulated follicles in recipient and donor does and ewes. An array of new criteria for selecting superior animals for NSER and NSET (e.g. cervical mapping) have been developed by Brazilian researchers. Extensive studies on both technologies were initially conducted in commercial breeds of goats and sheep but have been gradually extended to some native breeds of sheep (germplasm conservation) and dairy goat operations. It is speculated that, in future, NSER and NSET may become methods of choice for caprine and ovine embryo recovery and transfer in Brazil, and then globally. Due primarily to the efficiency of NSET in goats, a novel interspecies (e.g. bovine) IVP method may soon be developed on a large scale. The Brazilian experience is an invaluable source of information and know-how promoting the replacement of conventional surgical assisted reproductive technologies with non-surgical procedures and hence supporting the rapid development of the embryo transfer industry in small ruminants.

The wood bison (Bison bison athabascae) is a threatened Canadian species that has faced extinction twice in the last 100 yr. Development of assisted reproductive technologies could help ensure the long-term propagation and genetic management of this species. The objectives of this study were to refine estrus synchronization techniques and evaluate superovulatory responses after FSH or eCG administration. In Experiment 1, females were fitted with Syncro-mate B (SMB) implants for 9 d and received an injection of either estradiol valerate (E2V; n = 9) or cloprostenol (PGF; n = 9) at implant insertion (Day-9). In Experiment 2, estrus was synchronized with SMB implants and a PGF injection of Day-9, and superovulation was attempted on Day-2 with either 2500 IU eCG (n = 5) or 400 mg Folltropin-V (n = 5). In each experiment, biosin were examined daily for estrual behavior. Ultrasonography was used during the luteal phase to detect ovulation and assess ovarian status; feces were analyzed by ELISA for immunoreactive progestogens (P) to study ovarian endocrine responses. In Experiment 1, a closer synchrony of estrus was observed between Days 2 to 4 among the PGF-treated (77.8%) than the E2V-treated (66.7%) females. Corpora lutea (CL) were detected in 55% of E2V- and PGF-treated females. In Experiment 2, neither treatment successfully induced superovulation, with only a single female per treatment producing>> or = 1 CL. In both experiments, progestogen profiles were similar for each treatment (P < 0.05).

In an experiment involving 161 farrowings, cloprostenol was injected on day 112 or 113 of gestation at the recommended dosage (175 mug) or a lower dosage (125 mug). Cloprostenol treatment did not result in abnormally high body temperatures of sows at parturition. Farrowing began within 29 hours of injection in 94% and 88% of the sows treated with 175 mug and 125 mug cloprostenol respectively, as compared to 15% of saline-injected controls. The duration of farrowing and number stillborn were not affected by treatment. Sows farrowing within 19 hours of treatment tended to have a large number of piglets and a higher body temperature postpartum.

Three experiments were carried out to evaluate induction in ewes of superovulation and embryo production by a single injection of a porcine pituitary extract (pFSH) dissolved in polyvinylpyrrolidone (PVP), investigating the effects of PVP molecular weight and its concentration (Experiment I), time and method of treatment (Experiments II and III). All ewes were synchronized for estrus by vaginal sponges impregnated with fluorogestone acetate (FGA; 30 mg, 9 days) plus PGF(2alpha) (Cloprostenol, 50 microg, 48h before sponge removal - s.r.), and superovulated by 250 IU pFSH. In Experiment I, 60 Gentile di Puglia ewes were subdivided into five experimental groups (n = 12): Group A, the control, received six decreasing intramuscular (i.m.) doses of pFSH, 12 h apart, beginning 48h before s.r.; Groups B and C were given 48 h before s.r. a single i.m. injection of pFSH dissolved in PVP with MW = 10,000, respectively, at concentrations of 15 and 30% w/v; Groups D and E received the same treatments as for B and C using PVP with MW = 40,000. None of the pFSH-PVP treatments were effective in inducing superovulation. In Experiment II, 22 Leccese ewes were subdivided into two groups (n = 11): Group A, control received i.m. four decreasing doses of pFSH, beginning 24 h before s.r., 12h apart; Group B was given a single i.m. injection of pFSH dissolved in PVP (MW = 40,000 at 30% w/v), 24 h before s.r. The pFSH-PVP treatment provided an ovulation rate similar to the control and tended to enhance embryo yield (4.4 versus 2.4, P>0.05). In Experiment III, 60 Leccese ewes were subdivided into six treatment groups (n = 10). Groups A and D served as controls and received i.m. 12 h apart, six doses (from 48 h before s.r.) and four doses (from 24h before s.r.) of pFSH, respectively. Groups B and C were treated by a single injection of pFSH in PVP (MW = 10,000; 30% w/v) 48 h before s.r., respectively by i.m. or subcutaneous (s.c.) administration. Groups E and F received the same treatments as for B and C 24 h before s.r. Intramuscular pFSH-PVP administration 24 h before s.r. provided an ovulation rate (8.1), mean numbers of ova recovered (5.6) and fertilized (4.2) comparable to the six or four dose treatments and significantly higher (P <0.01) compared to the pFSH-PVP treatment carried out i.m. 48 h before s.r. These results show that a single injection of pFSH dissolved in PVP at 30% w/v, performed i.m. 24 h before s.r., is able to induce a superovulatory response comparable to that following multiple injection treatment, regardless of PVP molecular weight.

The present study evaluated the use of sex-sorted sperm upon estrus detection (ED) or following timed artificial insemination (TAI) in lactating dairy cows. Additionally, the effect of the presence of a corpus luteum (CL) at the beginning of the TAI protocol was verified. Cows (539 crossbred Gir × Holstein and 87 Holstein) were classified according to the presence or absence of CL by ultrasonography exam. Cows with a CL were randomly assigned into one of two groups (CL-ED/AI or CL-TAI), and cows without a CL (NoCL-TAI) received TAI. Cows from the CL-ED/AI group received 500mg of cloprostenol intramuscularly and were inseminated 12h after ED in the following five days. Cows from the TAI groups (CL or NoCL) received TAI. Cows receiving CL-ED/AI had a lower (P<0.0001) service rate (45.1%, 101/224) than TAI groups (CL-TAI=94.2%, 180/191 and NoCL-TAI=97.2%, 205/211). However, cows receiving AI upon ED (CL-ED/AI=31.7%, 32/101) presented higher (P=0.03) pregnancy per AI (P/AI) than cows bred following TAI (CL-TAI=19.4%, 35/180 and NoCL-TAI=23.9%, 49/205). Despite the lower P/AI, cows receiving TAI presented greater (P=0.07) proportion of pregnant cows at the end of the reproductive program (CL-TAI=18.3%, 35/191 and NoCL-TAI=23.2%, 49/211) than those inseminated upon ED (14.3%, 32/224). There was no effect (P=0.45) of the presence of a CL at the beginning of the synchronization protocol on P/AI. Thus, the use of TAI programs, regardless of the presence of CL in the beginning of the synchronization protocol, increases the service and pregnancy rates but reduces the P/AI when compared to the use of sex-sorted sperm upon ED.

In the present study, two new short estrus synchronization methods have been developed for lactating dairy cows. The study was completed in three consecutive phases. In experiment (Exp) 1, 32 cows, that were not detected in estrus since calving between the 50th and 84th post-partum days, were treated with PGF2alpha (PGF, d-cloprostenol, 0.150 mg), estradiol propionate (EP, 2mg) and GnRH (lecirelina, 50 microg) at 24h intervals, respectively, and timed artificial insemination (TAI) was performed 48 h after PGF. Different from Exp 1, EP and GnRH were given at 48 and 60 h, respectively after PGF in Exp 2 (n=20), instead of 24 and 48 h. Ovulations were investigated by ultrasound for 7 days starting from the day of PGF treatment, and ovulation rates were compared with the ones obtained in Exp 1. In Exp 3, cows were given the same treatments as Exp 2, but treatments started at certain estrus stages. Cows detected in estrus and with a confirmed ovulation (n=27) after the second PGF given 11 days apart were assigned to three treatment groups. Treatment was initiated at Day 3 (group metestrus, n=9), Day 12 (group diestrus, n=9) and Day 18 (group proestrus, n=9) after ovulation. All cows included in Exp 3 were TAI between 16 and 20 h after GnRH treatment. In Exp 2 and 3, blood samples were obtained once every 2 days, starting from Day 0 to the 10th day after GnRH injection, and once every 4 days between the 10th and the 22nd days after GnRH to examine post-treatment luteal development. During the study, animals exhibiting natural estrus were inseminated and served as controls (n=85). The rate of estrus was found to be significantly higher in cows with an active corpus luteum (CL) at the start of Exp 1 (72.7% vs. 30.0%, P<0.05) and the pregnancy rate tended to be higher than cows without an active CL (40.9% vs. 10.0%, P=0.08). Compared to those in Exp 1, cows in Exp 2 had higher rates of synchronized ovulation (94.1% vs. 59.1%, P=0.013). In Exp 3, estrus (P<0.001) and pregnancy rates (P=0.01) were found to be significantly higher in cows in the proestrus group than in those in the metestrus group. Comparable pregnancy rates were obtained from the first and second inseminations in Exp 1 and 3 with results from those inseminated at natural estrus (P>0.05). It was concluded from the study that the treatment in Exp 1 and 3 could result in comparable pregnancy rates after timed AI of lactating dairy cows at random stages of the estrus cycle relating to those inseminated at natural estrus, but the stage of the estrus cycle can have significant effects on pregnancy rates.

Previous research has reported evidence for negative effects of progestagens on follicular growth and oocyte competence. In the present study, negative effects of progestagens on follicular growth and oocyte developmental competence were assessed. During the breeding season, 20 Sarda ewes were treated with two doses of cloprostenol, 10 days apart, to assure the presence of a corpus luteum (CL). On day 5 after the second cloprostenol dose, 10 ewes were treated with a progestagen sponge while 10 females remained untreated. Starting on day 7 after the second cloprostenol dose, all the ewes were treated with 6 equal doses of 24 I.U. of FSH (Ovagen, ICP, NZ), every 12h. The number of follicles>> or =2mm in diameter increased (P<0.0005) in all the ewes from 24 h before to 60 h after the first FSH dose (from 12.8+/-1.1 to 23.4+/-1.3 in treated and from 12+/-0.6 to 22+/-1.2 in untreated ewes, n.s.). There were no significant differences in follicle dynamics between groups, but concentrations of estradiol in control ewes were higher than in the progestagen group (P<0.05). Twelve hours after the last FSH dose, oocytes were collected by ovum pick-up. Recovery rates were lower for progestagen-treated ewes (71.1 versus 83%; P<0.001). After IVP procedure, cleavage rate was also lower in the progestagen group (39.1 versus 82.6%; P<0.001). Furthermore, blastocysts output revealed that oocyte developmental competence was lower in progestagen group (17.3 versus 30.4%; P=0.245), although differences were not significant. These results suggest deleterious effects from progestagen on oocyte developmental competence and set the basis for new protocols for in vitro embryo production.

The weight, length, width and volume of ovaries were determined as well as the number of follicles visible on the surface in relation to the presence of corpus luteum on the ovary in autumn period after Cloprostenol application. The ovaries of 43 sheep of the Tsigai breed were examined at the age of 2--4 years. The animals were divided into five groups. First group (I) was the control (n = 6). In the luteal phase of sexual cycle the animals of groups II to V were applied i. m. 125 micrograms of cloprostenol in Oestrophan inf. Spofa preparation. According to groups II (n = 8), III (n = 10), IV (n = 9), V (n = 10) the animals were killed at intervals of 24, 48, 72 and 120 hours (h) from the preparation application. The removed ovaries were fixed in 10% neutral formalin; after a 48-hour fixation they were weighed and their length and width were measured. Tertiary follicles visible on the surface were counted and measured. In group I we demonstrated the significantly higher weight of ovaries with corpus luteum (CL) as compared with ovaries without CL (P less than 0.001). The weight of ovaries with CL dropped significantly within 48 hours after cloprostenol application as compared with control (P less than 0.001) and the difference in the ovary weight according to CL incidence disappeared almost completely. In comparison with groups III and IV, the weight of ovaries in ewes of group V increased statistically significantly (P less than 0.01) on 5th day from the cloprostenol application. This finding is a result of development of new CL after a passed ovulation. The alterations in length, width and volume of ovaries were not so significant as those in weight. The number of surface follicles was very variable and the changes were not significant. The changes in the average size of follicles larger than 1 mm and of the largest follicles have shown that both parameters achieved significantly higher values in ovaries of the control group with present CL in comparison with ovaries without CL. The reduction of surface follicles after cloprostenol application seems to be connected with a possible operation on contractile structures of the external theca folliculi.

After fading away of the effect of cloprostenol contained in the Oestrophan inj. Spofa preparation, the qualitative and quantitative changes in the epithelium of oviduct ampulla and isthmus of dairy cows were studied. Three dairy cows in the fourth to fifth day after heat were used as control, three cows with the rectally palpated active corpus luteum were given 0.5 mg cloprostenol i. m. On the eighth day after treatment, samples were taken from ampulla and isthmus by means of necropsy. After histological treatment, the samples were evaluated microscopically. Histological staining with hematoxylin-eosine, PAS reaction and PAS reaction with nucleus staining with Harris hematoxylin were used to describe the occurrence of the so-called pale cells. In accordance with the literary data, these cells are believed to be intraepithelial lymphocytes, the function of which will have to be further researched and determined objectively. On the eighth day after cloprostenol administration or on the fourth to fifth day after ovulation in the ipsilateral ovary, a significant decrease in epithelium thickness close to infundibulum and in the depth of ampulla (P less than 0.001) was observed. The changes in the contralateral left side were not significant. After cloprostenol application, the multiplication of nail-like cells in the right-side oviduct ampulla was statistically significant (P less than 0.05).

Content The objective of the study was to investigate whether a treatment with hCG 4 days after AI could reduce pregnancy losses in lactating dairy cows. Cows of a dairy herd presented to the veterinarian in a fixed reproductive management protocol were treated with an Ovsynch protocol if no corpus luteum (CL) could be palpated per rectum (Group OV). Cows with a CL received cloprostenol (0.15 mg). After 2 days, these cows were treated with buserelin (0.01 mg) and received timed AI 16-20 h later (Group PG). In both treatment protocols, cows were assigned to two groups to receive 2500 IU of hCG i.v. 4 days after AI or to serve as untreated controls (Groups OV-hCG, OV-Control, PG-hCG and PG-Control). Pregnancy diagnosis was carried out 27 days after AI via ultrasonography and 39 days after AI by rectal palpation. Pregnancy losses were defined as cows being pregnant on day 27 but not pregnant on day 39 after AI. Pregnancy rate (PR) by day 27 did not differ among the four groups (35.4, 35.0, 37.0 and 38.0% for Groups OV-hCG, OV-Control, PG-hCG and PG-Control, respectively). Pregnancy losses between day 27 and day 39 after AI were smaller in hCG treated animals in summer but not in autumn and spring. Pregnancy rate by day 39 after AI was higher in PG than in OV groups, but independent of hCG-treatment. In conclusion, treatment with hCG 4 days after AI did not significantly increase PR on 39 days after AI. A positive effect of hCG on pregnancy losses during the summer months warrants further investigation.

The polypeptide ubiquitin covalently binds to cytoplasmic proteins and marks them for proteolytic degradation. Ubiquitin is upregulated during apoptosis in some systems. Apoptosis increases during luteolysis but it is not known whether ubiquitin is expressed in regressing corpora lutea. Marmoset ovaries were removed on day 10 of the luteal phase from animals that had received either no treatment, treatment with the PGF2 alpha analogue cloprostenol 24 h earlier, or treatment with the GnRH antagonist antarelix for either 24 or 48 h before ovary collection. Ubiquitin was localized on ovarian sections by immunocytochemistry, and oligonucleosome formation characteristic of apoptosis was examined in isolated corpora lutea by electrophoresis of extracted [32P]DNA. Oligonucleosome formation was low in midluteal corpora lutea on day 10 but increased after induced luteal regression with PGF2 alpha and GnRH antagonist. Nuclear ubiquitin immunoreactivity was found in 1.66 +/- 0.66 steroidogenic cells and cytoplasmic staining was found in 0.4 +/- 0.3 steroidogenic cells (per x 40 field of view) in midluteal phase corpora lutea on day 10. Luteolytic induction with PGF2 alpha significantly increased the number of cells exhibiting cytoplasmic immunoreactivity to 12.24 +/- 1.6 (P < 0.05). Ubiquitin immunoreactivity was not observed after GnRH-induced luteal regression. Apoptotic oligonucleosome formation was found after induced luteal regression with both PGF2 alpha and GnRH antagonist, but ubiquitin upregulation only occurred after PGF2 alpha-induced regression. These results indicate that ubiquitin expression is not specific for luteolysis and is not an indicator of luteal apoptosis, but that the polypeptide does play a role in luteal cellular responses to PGF2 alpha.

The main objective of this study was to compare the effect of the presence of large follicles at the start of FSH treatment on the superovulatory response in ewes in the breeding and nonbreeding seasons. A second objective was to verify the effect on the superovulatory response of the presence of a corpus luteum at the start of the FSH treatment during the breeding season. Fifteen ewes in breeding season (October) and 14 in nonbreeding season (May-June) were treated with 40 mg FGA sponges (Chronogest) for 14 days, together with a single dose of 125 microg cloprostenol on Day 12, considering Day 0 as day of progestagen insertion. Superovulatory treatments consisted of eight decreasing doses (1.5 ml x 3, 1.25 ml x 2 and 1 ml x 3) of Ovagen twice daily from 60 h before to 24h after sponge removal. Ovarian structures were assessed by transrectal ultrasonography using a 7.5 MHz linear array probe. Luteal activity at progestagen insertion (Day 0) and presence of corpus luteum and of large follicles at first FSH dose (Day 12) were determined. There were no significant differences between the breeding season and nonbreeding season for ovulation rate (11.6+/-1.4 versus 11.6+/-1.3), number of recovered embryos (8.0+/-1.1 versus 9.6+/-1.3) or number of viable embryos (7.2+/-1.1 versus 5.8+/-1.2). During the breeding season, there were fewer recovered embryos in ewes with a large follicle >> or =6mm) at first FSH dose (6.9+/-1.1 versus 12.3+/-1.8, P<0.05) and fewer viable embryos (5.0+/-1.2 versus 10.5+/-0.5, P<0.05) than in ewes without such a follicle. During the nonbreeding season, however, there were no significant differences between ewes with or without a large follicle for either recovered (9.0+/-2.5 versus 11.3+/-1.2) or viable embryos (6.3+/-2.3 versus 8.1+/-1.2). Analysis of seasonal differences in ewes with a large follicle showed a lower number of recovered embryos in the breeding season (P<0.05) due to a lower recovery rate (65.7% versus 92.3%, P<0.05), since mean number of corpora lutea in response to the FSH treatment was similar (10.9+/-1.3 versus 10.0+/-2.5). These results indicate that, in sheep, the inhibitory effects of large follicles during the nonbreeding season are not as obvious as during the breeding season.

Changes in the plasma concentration of inhibin were measured by radioimmunoassay in ovarian venous blood collected at 10-min intervals for 5-h periods between 16 and 21 h and 40 and 45 h after cloprostenol-induced luteal regression in six Finn-Merino sheep. Episodes of inhibin secretion occurred with an interpulse interval of 66 +/- 5 min in both stages of the follicular phase. These changes in inhibin were unrelated to pulses of LH or oestradiol. There was no relationship with plasma concentrations of FSH, which did not change in a pulsatile manner. These results suggest that the release of inhibin by the preovulatory follicle(s) occurs in a pulsatile manner and is under local control by unknown factors.

The relationship between the opaqueness of the surface of bovine preovulatory follicles, degree of expansion of oocyte-cumulus investment, presence of perivitelline space, and abstriction of the first polar body was examined in heifers treated with PMSG (Group I), FSH-P (Group II), and FSH-P/GnRH (Group III). Follicles greater than 8 mm in diameter were inspected by laparoscopy 65 hours after treatment with cloprostenol in all groups and were classified as clear or opaque based on their surface appearance. Subsequently, oocytes were recovered from the follicles and characterized. The proportion of clear exceeded that of opaque follicles in all groups. The oocyte recovery rate was highest for clear follicles in Group I and II, while in Group III the rates were identical for clear and opaque follicles. The proportion of oocytes with expanded cumulus investment was highest in Group III. In Group II and I decreased proportions of expansion was seen especially among oocytes from opaque follicles. The proportion of oocytes with perivitelline space was highest in Group II and III. Again, this effect was most pronounced among oocytes from "opaque" follicles. The proportion of oocytes with a polar body was highest in Group III followed by Group II while only few oocytes in Group I displayed a polar body. It is concluded that treatment with FSH-P and especially in combination with GnRH reduced the incidence of follicular atresia as measured by opaqueness and improved oocyte quality as indicated by cumulus expansion, formation of the perivitelline space, and abstriction of the first polar body.

Twelve pony mares were randomly assigned to either a control or a treatment group and inseminated with fresh, raw semen from a single stallion of known fertility in a cross-over trial design. Pregnancy was diagnosed by transrectal ultrasound 12-14 days post-ovulation and then terminated by administration of a luteolytic dose of cloprostenol. Treatment mares received a uterine instillation of 100 ml of electrochemically activated (ECA) saline 4-12 hours post-insemination. Control mares received no treatment post-insemination. Per cycle pregnancy rate was 58.3 % in the control group and 50 % in the treatment group. There was no statistical difference (P = 1.000) in pregnancy rate between the 2 groups. The principles of ECA and applications of ECA saline are discussed.

Mature cyclic Holstein heifers were given a luteolytic dose of cloprostenol followed by two i.v. injections, 12 h apart, of various doses of [Ac-D-Nal1, D-p-Cl-Phe2, D-Trp3, D-Arg6, D-Ala10]-LHRH, beginning either at the time of first observation of behavioural oestrus, or 48 h after the cloprostenol injection. When treatment began at the first observation of oestrus, the time of ovulation, as determined by ultrasonic echography, was significantly delayed by total doses of 0.8 mg or more of the antagonist. When given at 48 and 60 h after cloprostenol injection, a total dose of 1.5 mg of the antagonist significantly delayed the growth of the ovulating follicle, the onset of oestrus, the preovulatory surges of oestradiol, LH and FSH, and ovulation. It is concluded that the LHRH antagonist can effectively suppress endogenous LH secretion and may therefore be useful in the study of follicular development, ovulation, and other events in the oestrous cycle of the cow.

Although spontaneous and medically induced canine embryonic or fetal death and "resorption" are clinically well documented, morphological studies of these processes are still missing. The objective of this study was therefore a detailed morphological investigation of canine placental sites after embryonic or fetal death. In five pregnant beagle bitches, embryonic or fetal death was induced by cloprostenol and cabergoline or by aglepristone. Two dogs served as untreated controls. Between Days 30 and 33 of gestation, the bitches were ovariohysterectomized, placental sites were fixed and examined by different methods. Morphological features of placental sites after both treatments were similar, finally leading to a complete disappearance of the placental labyrinth. Although there was an increase in the number of cells in the glandular chambers (superficial endometrial glands) expressing lysozyme after induced fetal death, signs of phagocytosis were absent in these cells, and no increased infiltration of maternal stroma by macrophages (compared to normal placental sites at the same time of gestation) occurred. We inferred that fetal and placental tissues were lysed, but no phagocytosis by genuine or "functional" macrophages was detectable. Further investigations are needed for a more detailed understanding of the morphological processes occurring after embryonic or fetal death in the dog.

The efficiency of superovulating mares with an enriched fraction of equine follicle-stimulating hormone (feFSH) and an equine pituitary extract (EPE) with similar FSH content but differing in the LH amount was compared. Mares were randomly assigned to an feFSH (n = 5) or EPE (n = 5) treatment. The experimental period was of 2 successive estrous cycles, with the first cycle as the control. At Days 6 and 7 of the estrous cycle, the mares received 250 micrograms i.m. cloprostenol. The treatments consisted of daily injections of 25 mg feFSH or EPE beginning on Day 6 post ovulation. Mares were inseminated every other day until the last ovulation was detected. When the mares in the control and treatment cycles developed at least 1 or 2>> or = 35-mm follicle, respectively, the treatment was interrupted, and a single injection of EPE (25 mg, i.v.) was administered to induce ovulation(s). Nonsurgical embryo recovery was performed 6 or 7 d after ovulation in both control and treatment cycles. The number of ovulations per mare was not significantly different (P>> 0.05) between feFSH and EPE groups, but both were higher (P < 0.05) than that of the control cycle. The number of recovered embryos per ovulation was similar (P>> 0.05) for control, feFSH and EPE groups. The high amount of LH presented in EPE did not affect the superovulatory response of the mares. Superovulatory treatments increased the ovulation rate of mares but did not affect the embryo recovery rate per ovulation.