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The aim of this study was to investigate a) the effect of equine Chorionic Gonadotropin (eCG), in the dosage used for oestrus synchronization or for superovulation, on the activity of α-mannosidase (α-MAN) and β-N-acetyloglucosaminidase (β-NAGASE) in the genital tract of ewes before maternal recognition of pregnancy and b) the possible relationships among ovarian steroids concentration, glycosidase activity and embryo yield and quality. Twenty-four Chios ewes were treated with progestagen intravaginal sponges for 12 days and eCG [superovulation (SOV), n = 7, 1000 IU; oestrus synchronization (OS), n = 7, 500 IU; controls (C), n = 10, 0 IU] at sponge removal. Ovarian response was assessed and embryos were collected on day 6 of the oestrous cycle, after slaughter. Oestradiol-17β and progesterone concentrations were determined in blood serum samples collected before slaughter using a radioimmunoassay. The activities of α-MAN and β-NAGASE were assayed, photometrically, in uterine horn flushing (UHF) samples, caruncular endometrium (CE) and intercaruncular (ICE) endometrium samples, collected after slaughter. Alpha-MAN activity was higher in the UHF, CE and ICE of SOV ewes, as well as in the UHF and ICE of OS ewes, compared to controls. Beta-NAGASE activity in the UHF and in the ICE of SOV ewes was lower than in C ewes. Alpha-MAN activity in the UHF was positively correlated with the response to superovulation in terms of total recovered structures, embryos or high-quality embryos collected from the ewes. Beta-NAGASE activity in the CE correlated to the number of corpora lutea observed on the ovaries, at the day of embryo collection. Beta-NAGASE activity in UHF and α-MAN activity in the ICE were negatively related to oestradiol-17β concentration in blood serum; β-NAGASE activity in UHF and in ICE was negatively related to progesterone concentration in blood serum. In conclusion, eCG in the dosage used for superovulation and, in a lesser degree, in the dosage used for oestrus synchronization affects glycosidase activity in the genital tract of Chios breed ewes, before maternal recognition of pregnancy; glycosidase activity in the genital tract correlate to ovarian response and embryo yield. Further research is necessary to fully clarify the interrelationship between ovarian steroids concentration and glycosidase activity in the genital tract of ewes after hormonal treatment.

The purpose of the present study was to investigate whether the electrical resistance values of the cer - vical mucus and/or blood οestradiol-17β and progesterone concentrations at mating, after oestrous synchronisation during the anoestrous or oestrous period in ewes, are related to fertility. Oestrus was induced by medroxyprogesterone acetate-impregnated intravaginal sponges (Veramix, Upjohn, USA), either for 12 days (12-day group; 24 Kymi and 28 Chios) or for 14 days (14-day group; 24 Kymi and 28 Chios), plus 400 IU equine chorionic gonadotropin (Intergonan, Intervet, the Netherlands) i.m., at the time of sponge removal. In each case, one blood sample was collected from all ewes at sponge insertion, at sponge removal and at oestrus, for the determination of serum οestradiol-17β and progesterone concentrations, using a radioimmunoassay. The electrical resistance of the cervical mucus was meas - ured once, just after oestrus detection by teaser rams, using a digital heat detector. All ewes found to be in oestrus were mated to fertile rams. Pregnancy was determined by transabdominal ultrasonography 35-40 days after mating. Kymi ewes were in anoestrous, while those of Chios were in the oestrous period. The 14-day treatment resulted in better outcome as concerns oestrus detection and pregnancy rate than the 12-day treatment, in either oestrous or anoestrous period ewes. Oestradiol-17β concentrations at sponge removal and at oestrus were lower ( P < 0.05) in the 14-day group than in the 12-day group, in both oestrous or anoestrous period ewes. Progesterone concentrations at sponge insertion and removal were higher ( P < 0.05), while progesterone concentrations and electrical resistance values of the cervical mucus at oestrus were lower ( P < 0.05) in ewes of both groups who conceived compared to those that did not, either in oestrous or in the anoestrous period. Linear regression analysis revealed a positive relation between the electrical resistance values of the cervical mucus and blood serum progesterone concentrations in both oestrous or anoestrous period ewes. The electrical resistance of cervical mucus could be useful for the detection of the proper time for mating after oestrous synchronisation in ewes.

The purpose of this study was to investigate whether fertile or non-fertile inseminations (AI) in synchronized ewes are correlated with the electrical resistance of cervical mucus (ERCM) and the ovarian steroid concentration. AIs were performed either at fixed-time (group A) or after estrus detection (group B). Retrospective analysis revealed that at AI, pregnant ewes had lower ERCM values and progesterone concentrations than non-pregnant ones (p < 0.05). It appears that ERCM may be used as an additional index for fertility enhancement of inseminated ewes.

We studied the role of follicular fluid's (FF) glycosidase (α-mannosidase [α-ΜΑΝ], β-Ν-acetyloglucosaminidase [NAGASE], β-galactosidase [β-GAL]) activity during IVM of bovine oocytes. Oocytes were allocated into two groups according to the follicular size (small follicle [SF]: 2–5 mm, large follicle [LF]: >5–8 mm). In experiment 1, cumulus–oocyte complexes (COCs) quality was evaluated according to morphologic criteria (grades A, B–C, D); oocyte (n = 801) nuclear maturation was assessed after 24 hours of incubation. Bovine embryos were produced in vitro in groups (experiment 2, n = 1503 oocytes) or individually (experiment 3, n = 50 oocytes). More grade-A and -BC COCs were collected from SF and LF groups, respectively (P

Σκοπός της μeλέτης ήταν η αξιολόγηση της ανταπόκρισης στην αγωγή για πρόκληση οίστρου σe προβατίνeς των φυλών Σκοπέλου, Ζακύνθου και Κύμης. Eπίσης, διeρeυνήθηκe η δυνατότητα προσδιορισμού της ηλeκτρικής αντίστασης της τραχηλικής βλέννας για προσδιορισμό προβατίνων σe οίστρο. Η πρόκληση οίστρου έγινe μe eνδοκολπική τοποθέτηση σπόγγων eμποτισμένων μe 60 mg οξικής μeδροξυπρογeστeρόνης eπί 12 ημέρeς [προβατίνeς Σκοπέλου (n=17), Ζακύνθου (n=18), Κύμης (n=22)], ακολουθούμeνη από eνδομυϊκή ένeση 400 IU ίππeιας χοριακής γοναδοτροπίνης. Δeίγματα αίματος, για προσδιορισμό της συγκέντρωσης οιστραδιόλης 17β και προγeστeρόνης, συλλέχθηκαν 10 ημέρeς πριν από την eισαγωγή των σπόγγων, κατά την eισαγωγή και την αφαίρeση αυτών και τον οίστρο. Η ηλeκτρική αντίσταση τραχηλικής βλέννας προσδιορίστηκe αμέσως μόλις οι προβατίνeς ανιχνeύτηκαν σe οίστρο και, τeλικά, πραγματοποιήθηκαν eλeύθeρeς οχeίeς. Η αναλογία προβατίνων που eκδήλωσαν οίστρο στα ζώα φυλής Ζακύνθου (100%), ήταν μeγαλύτeρη από αυτήν στα ζώα φυλής Κύμης (64%) ή Σκοπέλου (78%). Το ποσοστό eγκυμοσύνης κυμάνθηκe από 50% (προβατίνeς Κύμης) έως 67% (προβατίνeς Σκοπέλου). Σe προβατίνeς που κυοφόρησαν, η ηλeκτρική αντίσταση τραχηλικής βλέννας ήταν σημαντικά μικρότeρη από αυτήν σe προβατίνeς που δeν ήταν έγκυeς τeλικά. Λαμβάνονταν υπόψη τη συγκέντρωση της προγeστeρόνης 10 ημέρeς πριν την eισαγωγή των σπόγγων και κατά την eισαγωγή αυτών, οι προβατίνeς της φυλής Κύμης βρίσκονταν σe άνοιστρο, eνώ αυτές των φυλών Σκοπέλου και Ζακύνθου βρίσκονταν σe οιστρική πeρίοδο. Η συγκέντρωση της προγeστeρόνης κατά την αφαίρeση των σπόγγων και της οιστραδιόλης-17β κατά τον οίστρο, στις προβατίνeς της φυλής Ζακύνθου που κυοφόρησαν, ήταν σημαντικά μeγαλύτeρη από τις αντίστοιχeς σe αυτές που δeν κυοφόρησαν. Eπίσης, η συγκέντρωση της προγeστeρόνης κατά την eισαγωγή των σπόγγων ήταν σημαντικά μeγαλύτeρη σe όλeς τις προβατίνeς που κυοφόρησαν σe σύγκριση μe αυτές που δeν κυοφόρησαν. Σημαντικές διαφορές παρατηρήθηκαν στις συγκeντρώσeις της προγeστeρόνης και της οιστραδιόλης 17β μeταξύ των τριών φυλών, σe διάφορeς φάσeις του πeιραματισμού. Συμπeραίνeται ότι, οι προβατίνeς των σπάνιων φυλών ανταποκρίθηκαν ικανοποιητικά στην αγωγή πρόκλησης οίστρου. Το ορμονικό πρότυπο των προβατίνων κατά την eισαγωγή των σπόγγων eίναι σημαντικό για την κυοφορία. Η μέτρηση της ηλeκτρικής αντίστασης της τραχηλικής βλέννας θα μπορούσe να χρησιμοποιηθeί για την eντόπιση των προβατίνων που θα οχeυθούν, ακόμα και στην πeρίπτωση που χρησιμοποιούνται κριοί για την ανίχνeυση των οίστρων.

Follicular development and oocyte quality were assessed by laparoscopic observation and in vitro fertilisation, respectively, in melatonin-treated (Group M) and control (Group C) anoestrous Chios ewes (n = 10 in each group). Fourteen days after melatonin insertion, all ewes had laparoscopic evaluation of the follicular population followed by oocyte pick-up (OPU); on day 22 intravaginal progestagen sponges were inserted for 14 days. Two days after sponge removal the follicular population was re-evaluated and a second follicular aspiration was performed. Collected oocytes from the second OPU underwent in vitro maturation, fertilisation and culture. The number of large follicles was higher in Group M than in the control ewes during the first OPU and tended to be so (P = 0.06) at the second. Morphologically, oocytes collected from controls were of better quality than those from Group M; however, more oocytes collected from melatonintreated animals fertilised and developed in vitro . These results indicate that melatonin is a potent regulator of follicular development and oocyte competence during the anoestrous period of the ewe.

The purpose of the present study was to investigate the feasibility of improving the synchronisation of lambing after oestrus synchronisation and artificial insemination (AI). To this end, low doses of dexamethasone 21-isonicotinate (DEX) alone or in combination with prostaglandin F 2a (PG) were used in five treated groups (n = 20 each) and one control group (n = 136) of Chios ewes. On day 143 of pregnancy 1.5 mg DEX was given in Group 5, while on day 146 the following treatments were applied: 0.0375 mg PG in Groups 4 and 5, and 1, 1.5 and 2 mg of DEX in ewes of Groups 1, 2 and 3, respectively. The control ewes received no treatment. The 1.5 and 2 mg dose of DEX was more effective in synchronising labour as regards the treatment to lambing interval and the proportion of ewes that gave birth within 3 days. However, obstetrical manipulations were needed, and dead lambs were born when 2 mg DEX was used. It was concluded that lambing can be safely synchronised in Chios ewes with 1.5 mg DEX given on day 146, without affecting the viability of lambs and without parturition complications.

The paper demonstrates the efficient use of hybrid intelligent systems for solving the classification problem of splice-junction gene sequences. The aim of the study is to obtain classification schemes able to recognize, given a sequence of DNA, the boundaries between exons and introns. Previous attempts to form efficient classifiers for the same problem using intelligent or standard statistical techniques are discussed throughout the paper. The authors propose the use of evolutionary neural logic networks, an advantageous approach for their ability to interpret their structure into expert rules, a desirable feature for field experts. Evolutionary neural logic networks in fact consist an innovative hybrid intelligent methodology, by which evolutionary programming techniques are used for obtaining the best possible topology of a neural logic network. The genetic programming process is guided using a context-free grammar and indirect encoding of the neural logic networks into the genetic programming individuals. Indicative classification results are presented and discussed in detail in terms of both, classification accuracy and solution interpretability.

1. A study was conducted with 120 female early maturing turkeys to test the effect of dietary dried oregano leaves (Origanum vulgare subsp. hirtum) on body weight (BW), feed intake (FI), feed conversion efficiency (FCE), carcase characteristics and serum cholesterol concentration. Dried oregano leaves had a content of 3.6 ml essential oils/100 g, while the carvacrol content was 855 g/kg of the total essential oils. 2. From 1 to 84 d of age, the turkeys were fed on 4 diets varying in oregano content (OR0, no oregano--control; OR45, 1.25 g oregano/kg; OR90, 2.5 g oregano/kg; OR135, 3.75 g oregano/kg). Birds were given feed and water ad libitum. 3. BW was unaffected by oregano throughout the experiment. FI and FCE were similar among all treatments until 42 d of age. From 43 to 84 d of age and for the overall experimental period, FI decreased linearly in treatment OR135 and FCE increased linearly with dietary oregano content. Body and carcase weights, carcase yield, and the relative weights of the heart and liver were not significantly affected by oregano content. The relative weights of the gizzard and small intestine decreased linearly with oregano content. Serum cholesterol content was similar among all treatments. 4. In the present study, dietary oregano (1.25, 2.5 and 3.75 g/kg) improved FCE in female early maturing turkeys between 43 and 84 d, with the lowest oregano inclusion (1.25 g/kg) giving the most cost effective diet. Thus, dried oregano leaves may be used as a natural herbal growth promoter for early maturing turkeys.

Ninety two Friesian cows were used to determine physical properties of cervical mucus collected during normal estrus and estrus induced. Estrus was induced using either progesterone (P4) releasing intravaginal devices (PRID) and/or prostaglandin F2alpha (PGF2alpha). The animals were assigned to 4 groups (no treatment, a PRID for 12 days plus an injection of 1000 IU PMSG at the removal of the PRID, a double injection of 3 mL PGF2alpha 11 days apart, and a PRID for 7 days plus an injection of PGF2alpha 24 h before the removal of PRID). A number of cows with normal estrus exhibited three consecutive estrus cycles after calving. Cows that had not shown estrus for three months after calving had their reproductive system palpated twice at 10-day intervals, to determine their ovarian activity. Then PRID and/or PGF2alpha was administered to cows that were found to have a palpable corpus luteum in one of two palpations (cycling cows). The cows of the three induced estrous groups were artificially inseminated (AI) twice, while those with normal estrus received only a single AI. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. Additionally, samples of cervical mucus were collected from 20 cows at their first estrus after the induced estrus. The results are summarized as follows: 1) The physical properties of cervical mucus were similar in the first three normal consecutive estrus cycles after calving. 2) The physical properties of cervical mucus in normal estrus after calving were similar to those in the first estrus after an induced estrus. 3) The pH values for normal estrus were similar to those for induced estrus. 4) Viscosity of cervical mucus in the normal estrous group was significantly lower than that in the induced estrus. Furthermore, significant differences were noticed among the three induced estrous groups. 5) Spinnbarkeit, crystallization and receptivity of cervical mucus (penetration test) were significantly higher in the normal estrous group than in the induced estrous groups, while no difference was detected among induced estrus groups. 6) Pregnancy rates in the normal estrus group were the same as in the induced estrus groups. 7) The percentages of cows in the induced estrous groups that produced cervical mucus with similar viscosity, spinnbarkeit and receptivity (penetration test) characteristics as the normal estrus group, was very low.

Ghrelin is a gastric peptide having regulatory role in the reproductive system functionality, acting mainly at central level. Because the expression of ghrelin system (ghrelin and its receptor) has been detected in the bovine ovary, the objectives of the present study were to investigate whether ghrelin can affect the developmental potential of invitro-produced embryos, and to test their quality in terms of relative abundance of various genes related to metabolism, apoptosis and oxidation. In the first experiment, invitro-produced zygotes were cultured in the absence (control [C]) and in the presence of three concentrations of acylated ghrelin (200 pg/mL [Ghr200], 800 pg/mL [Ghr800]; and 2000 pg/mL [Ghr2000]); blastocyst formation rates were examined on Days 7, 8, and 9. In the second experiment, only the 800 pg/mL dose of ghrelin was used. Zygotes were produced as in experiment 1 and 24 hours post insemination they were divided into 4 groups; in two groups (C; without ghrelin; Ghr800 with ghrelin), embryos were cultured without medium replacement; in the remaining two groups (Control N and GhrN), the culture medium was daily renewed. A pool of Day-7 blastocysts were snap frozen for relative mRNA abundance of various genes related to metabolism, oxidation, implantation, and apoptosis. In experiment 3, embryos were produced as in experiment 2, but in the absence of serum (semi-defined culture medium). In experiment 1, no differences were detected between C, Ghr200, and Ghr2000, although fewer blastocysts were produced in group Ghr800 compared with C. In experiment 2, the lowest blastocysts yield was found in Ghr800, whereas daily renewal of ghrelin (Ghr800N) resulted to increased blastocysts formation rate, which on Day 7 was the highest among groups (P < 0.05). In experiment 3, ghrelin significantly suppressed blastocysts yield. Significant differences were detected in various relative mRNA abundance, giving an overall final notion that embryos produced in the presence of ghrelin were of better quality than controls. Our results imply a specific role of ghrelin in early embryonic development; however, the specific mode of its action needs further investigation. © 2014 Elsevier Inc.

Evaluate the results obtained from Quantitative Fluorescent (QF)-PCR and conventional karyotype analysis to determine the advantages and disadvantages of dual testing in prenatal diagnosis.From 1 June 2006 to 1 June 2010, dual testing by QF-PCR and karyotype analysis was performed in 13,500 prenatal samples. The rates of concordant results between the two methods were evaluated and the rates of clinically significant chromosomal abnormalities undetected by QF-PCR were assessed.Abnormal karyotype was found in 320 out of 13,500 cases (2.37%, 95% confidence interval (CI) 2.11-2.63%). From these, QF-PCR did not detect the abnormality in 70 cases (0.52%, 95% CI 0.4-0.64%), whereas 34 had a high/unknown risk of adverse outcome (0.25%, 95% CI 0.17-0.33%). By selectively applying dual testing only at cases with ultrasound findings and/or genetic history, 13 cases of high/unknown risk would have been missed (0.1%, 95% CI 0.05-0.15%).Selective dual testing is expected to achieve a serious beneficial economical outcome and reduce parental anxiety produced by ambiguous cytogenetic findings. However, the percentage of 0.1% undetected clinically significant abnormalities cannot be ignored. A suggestion would include the offering of a choice to the pregnant women, undergoing prenatal screening, by informing them about different approaches and various complications.

Possible associations between certain physical properties of cervical mucus (CM) and ovulation rate were studied in 21 superovulated Holstein cows. In CM samples collected at the beginning of estrus (0 h) and in 4 h intervals for the following 24 h, the pH, the spinnbarkeit (spinability), and the crystallization value were measured. Blood samples, collected at the same time points with CM samples, were assessed for progesterone and estradiol concentrations. At 48 h the number of ovulated follicles was counted by transrectal ultrasonography and the animals were allotted into 2 groups according to the occurrence of at least one (group A, n = 16) or no (group B, n = 5) ovulations. The pH was lower (P0.05) at 8 h (7.00 + 0.24) in group A compared with group B (7.55 + 0.12). In group A, spinnbarkeit was significantly lower at 0 h and 20 h, and higher at 8 h and 16 h compared with group B (0 h: 2.50 + 0.82 versus 6.95 + 0.41; 20 h: 3.00 + 1.89 versus 5.38 + 0.94; 8 h: 7.00 + 0.87 versus 2.75 + 0.43; 16 h: 7.00 + 1.41 versus 4.30 + 0.71, for groups A versus B, respectively). Crystallization was significantly lower at 4 h (2.00 + 0.63) and 20 h (1.50 + 0.82) in group A compared with group B (3.13 + 0.32 at 4 h and 3.00 + 0.41 at 20 h). Progesterone at all time points, and estradiol at 16 h, 20 h, and 24 h were lower (P0.05) in group A than in group B. The pH, crystallization, estradiol, and progesterone differed (P0.05) within one group, while sbk differed within both groups.Our results imply that during the periovulatory period, steadily low progesterone concentrations trigger alterations of certain CM characteristics, while extremely high estradiol concentration could prevent the occurrence of these alterations.

A field study was designed to compare ovarian response and embryo yield in cows during early lactation when gonadotropin administration followed one of four treatments. In group 1A (n = 19) and 1B (n = 9), the estrouses were synchronized by two prostaglandin F2alpha (PG) injections given 11 days apart, and starting from day 9 of the synchronized cycle superovulation was conducted with eight decreasing dose of FSH. In group 1B, ablation of all follicles >3 mm was carried out on day 8. In group 2A and 2B (each n = 9), a progesterone plus oestradiol intravaginal device (PRID) was inserted for 11 days and gonadotropin administration started on day 9, while cows from group 2B had a follicle ablation on day 8. In all groups, two PG injections were given along with the sixth and the seventh dose of FSH, and the cows were twice inseminated 12 and 24 h after estrus detection. Embryos were collected on day 7. In cumulative results from aspirated and non-aspirated cows, follicular ablation significantly improved: the ovarian response (10 +/- 1.23 vs 6.69 +/- 0.60 corpora lutea per donor), the mean collected embryos (6.57 +/- 0.94 vs 2.46 +/- 0.53) and the mean transferable embryos (4.43 +/- 0.89 vs 2.18 +/- 0.47). Group 1B and 2B cows had better ovarian response than 1A (6.44 +/- 0.81, 12.25 +/- 4.11 and 9.44 +/- 0.93, for groups 1A, 1B and 2B, respectively, p < 0.05). Similarly, from groups 1B and 2B more (p < 0.05) embryos were collected in comparison with their respective group, while the mean transferable embryos from group 2B (5.22 +/- 1.13) was greater (p < 0.05) than that of group 1A (1.67 +/- 0.35), and tented to be greater than those of groups 2A (3.44 +/- 1.19, p = 0.062) and 1B (3.00 +/- 1.78, p = 0.066). The highest (p < 0.05) transferable embryo collection rate was recorded in group 2B (55.29%), followed by that of group 1B (41.33%). In summary, early in lactation, an acceptable number of transferable embryos can be collected from high producing dairy cows, when follicle ablation prior to superovulation is combined with progesterone and oestradiol administration.

Glycosidases are enzymes with a potential role in embryonic development. The objectives of this study were to assess: (a) whether in vitro bovine embryonic development is affected by the addition of beta-N-acetyloglucosaminidase (beta-NAGASE) and/or alpha-mannosidase to the culture medium and (b) whether these enzymes are utilized by bovine embryos during their development in vitro. Bovine embryos were produced using standard methods of IVM, IVF and IVC. Presumptive zygotes were cultured in groups of 20 in 50 microl drops of SOF medium (plus 5% FBS after 24 h culture) incubated in 5% CO2, 5% O2 and 90% N2 at 38.5 degrees C. The groups of zygotes were allocated to four treatments in which the culture medium was supplemented with: (1) beta-NAGASE, (2) alpha-mannosidase, (3) beta-NAGASE plus alpha-mannosidase, and (4) control (no supplement). Embryos were evaluated and samples of culture medium collected and frozen prior to assay for glycosidases at day 7 of culture. The experimental design was a randomised block arrangement of 4 treatments x 7 replicates with 20 zygotes per plot (culture droplet). Data were analysed by ANOVA and presented as mean +/- S.E.M. The osmolarity of the control culture medium was 272 mOsm. This was increased to 279 mOsm by the addition of alpha-mannosidase, 424 mOsm by beta-NAGASE and 337 mOsm with a combination of the two enzymes. The beta-NAGASE supplemented medium and the combined supplement reduced (0%) the development of zygotes to morula or blastocyst stages (P0.002) relative to control medium (35.7 +/- 8.4%). Embryo development was also reduced to 21.9 +/- 3.2 (P0.002), relative to control, by alpha-mannosidase supplementation. The reduced embryo development in the beta-NAGASE-supplemented medium was attributed to increased osmolarity of the culture medium. Embryos appeared to utilize alpha-mannosidase because its concentration decreased from 600.95 +/- 174.03 IU/l in drops without zygotes/embryos to 211.01 +/- 71.59 IU/l in drops with zygotes/embryos. Other culture media supplementation showed no significant differences between droplets, with or without zygotes/embryos. It was concluded that beta-NAGASE increased medium osmolarity, embryos utilized alpha-mannosidase and both glycosidases (singly or in combination) inhibited the development of bovine zygotes to morulae/blastocysts.

Ninety-two Friesian cows were used to determine the chemical properties of cervical mucus during normal estrus and estrus induced by progesterone (P4)-releasing intravaginal devices (PRID) and/or prostaglandin F2alpha. The animals were assigned to 4 groups (no treatment, a PRID for 12 days plus injection of 1000 IU PMSG at the removal of PRID, a double i.m. injection of PGF2alpha 11 days apart, or PRID for 7 days plus an im injection of PGF2alpha 24 h before the removal of PRID). A number of cows with normal estrus exhibited three consecutive estrous cycles after delivery. Cows that had not shown estrus for 3 months after delivery had their ovaries palpated twice at 10-day intervals, to determine their ovarian activity. Then PRID and/or PGF2alpha was administered in cows that had a palpable corpus luteum in one of the two palpations (cyclic cows). A double artificial insemination (AI) was performed to the cows of the three induced-estrus groups, while the cows with normal estrus received only one AI. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. Additionally, samples of cervical mucus were collected from 20 cows during their first estrus after the induced one. The results are summarized as follows: 1) The biochemical properties of cervical mucus in the first three estrus periods after delivery were similar. 2) These properties were similar both in normal estrus after delivery and in the first estrus after an induced one. 3) Glucose and fructose concentrations for normal estrus were similar to those for induced estrus groups. 4) Total protein and cholesterol concentrations were significantly lower (P < 0.001) in normal than in induced estrus, while no difference was found among the induced estrus groups. 5) Pregnancy rates of the cows did not differ significantly among the normal and the induced-estrus groups. 6) The percentages of cows in the induced-estrus groups that produced cervical mucus with total protein and cholesterol concentrations similar to those for the normal estrus groups was very low.

Ninety-two healthy Friesian cows were used to determine the concentration of calcium (Ca), zinc (Zn), magnesium (Mg), potassium (K) and sodium (Na) in bovine cervical mucus and to compare these concentrations in cervical mucus collected during spontaneous and induced oestrus. Cows were assigned to four groups: (1) no treatment (2) PRID for 12 days plus pregnant mare's serum gonadotrophin (PMSG; 1000 IU, i.m.) at the removal of the PRID (3) PGF2α , two doses (6 mg, i.m.) 11 days apart, and (4) PRID for 7 days plus one dose of PGF2α (6 mg, i.m.) 24 h before removal of the PRID. The cows of the three induced-oestrus groups received two artificial inseminations (AI), whereas those in the spontaneous-oestrus group received only one. Cervical mucus samples were collected from all cows 5 to 30 min before the first AI. The results of this study can be summarized as follows: (1) viscosity was significantly lower (P