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1.
The objective was to compare populations of antral and pre‐antral ovarian follicles in Bos indicus and Bos indicus‐taurus cows with high and low antral follicle counts. Nelore (Bos indicus, n = 20) and Nelore X Angus (1/2 Bos indicus‐taurus, n = 20) cows were subjected to follicular aspiration without regard to the stage of their oestrous cycle (day of aspiration = D0) to remove all follicles ≥3 mm and induce growth of a new follicular wave. Ovaries were examined by ultrasonography on D4, D19, D34, D49 and D64, and antral follicles ≥3 mm were counted. Thereafter, cows were assigned to one of two groups: high or low antral follicular count (AFC, ≥30 and ≤15 antral follicles, respectively). After D64, ovaries were collected after slaughter and processed for histological evaluation. There was high repeatability in the numbers of antral follicles for all groups (range 0.77–0.96). The mean (±SD) numbers of antral follicles were 35 ± 9 (Bos indicus) and 38 ± 6 (Bos indicus‐taurus) for the high AFC group and 10 ± 3 (Bos indicus) and 12 ± 2 (Bos indicus‐taurus) follicles for the low AFC. The mean number of preantral follicles in the ovaries of Bos indicus‐taurus cows with high AFC (116 226 ± 83 156 follicles) was greater (p < 0.05) than that of Bos indicus cows (63 032 ± 58 705 follicles) with high AFC. However, there was no significant correlation between numbers of antral and preantral follicles.  相似文献   

2.
The aim of the present study was to compare the lipid profile in oocytes of indicus and 1/2 indicus × taurus cows with high and low antral follicle count (AFC)/oocyte yields. After an OPU procedure (D0), antral follicles ≥3 mm were counted by ultrasonography (D4, 19, 34, 49, 64), and cows were assigned to groups with either high AFC (≥30 follicles; indicus, NH group; 1/2 indicus × taurus, AH group) or low AFC (≤15 antral follicles; indicus, NL group; 1/2 indicus × taurus, AL group). The lipid profiles of the oocytes were determined by MALDI‐MS. For GI, GII and GIII oocytes, the indicus samples tend to cluster separately from the 1/2 indicus × taurus samples. The lipid species [PC (P‐38:5) + H]+ and/or [PC (P‐36:2) + Na]+, [PC (38:2) + H]+, [PC (38:5) + Na]+ and [TAG (60:8) + NH4]+ were more abundant in indicus (NH and NL groups) than 1/2 indicus × taurus. The higher lipid content in the indicus oocytes likely reflects differences in the rate of lipid metabolism and may contribute to oocyte competence and embryo development.  相似文献   

3.
The current study investigated the possibility of using the AMH concentration as a predictor of the ability of Korean Hanwoo cows to produce cumulus‐oocyte complexes, embryos that survive after transfer as well as the pregnancy outcome of surrogates. Eight sessions of ovum pick‐up (OPU) were performed with 19 donor cows at an interval of 3–4 days. Antral follicle count (AFC), oocyte quality and in vitro embryo development were recorded for each cow. Embryos produced from cows with different AMH profiles were transferred into recipients (n = 96). Cows in the high (≥0.25 ng/ml) and intermediate (0.1≥ to <0.25 ng/ml) AMH groups had a significantly higher AFC per OPU session (20.40 ± 1.36 and 16.91 ± 1.52, respectively; mean ± standard deviation) than cows in the low AMH group (<0.1 ng/ml; 12.19 ± 2.14). In addition, more cumulus‐oocyte complexes per donor were recovered in the high (11.46 ± 1.22) and intermediate (7.38 ± 0.83) AMH groups than in the low AMH group (4.77 ± 0.44). The percentage of oocytes reached blastocyst stage was significantly higher in the intermediate (47.0%) and high (38.5%) AMH groups than in the low AMH group (32.3%). The number of embryos produced per cow was higher in the high (3.9 ± 0.2) and intermediate (6.9 ± 0.6) AMH groups than in the low AMH group (2.2 ± 0.3). The percentage of embryos that gave birth to viable calves when transferred into recipients was higher for those derived from cows in the intermediate AMH group (50.7%) than for those derived from cows in the low (35.7%) and high (36.4%) AMH groups. In conclusion, a single measurement of AMH concentration predicted the in vitro embryo production potential of donor Korean native cows before OPU and is linked with embryo viability after transfer into recipients.  相似文献   

4.
The objective of this study was to determine apoptotic cell localization in preantral and antral follicles of porcine ovaries. Additionally, the proportion of cells undergoing apoptosis was also compared between delayed puberty gilts and normal cyclic gilts. Ovarian tissues were obtained from 34 culled gilts with age and weight of 270.1 ± 3.9 days and 143.8 ± 2.4 kg, respectively. The gilts were classified according to their ovarian appearance as ‘non‐cyclic’ (n = 7) and ‘cyclic’ (n = 27) gilts. The terminal deoxynucleotidyl transferase‐mediated dUTP nick end labelling (TUNEL) assay was used to determine apoptotic cell expression in different compartments of the ovarian tissue sections. All apparent preantral (n = 110) and antral (n = 262) follicles were evaluated using image analysis software. It was found that apoptotic cells were expressed in both granulosa (22.2%) and theca cell layers (21.3%) of the follicles in the porcine ovaries. The proportion of apoptotic cells in the granulosa layer in the follicles was positively correlated with that in the theca layer (r = 0.90, p < 0.001). Apoptosis did not differ significantly between preantral and antral follicles in either granulosa (27.8% and 26.4%, p > 0.05) or theca cell layers (28.6% and 26.5%, p > 0.05). The proportion of apoptotic cells in non‐cyclic gilts was higher than cyclic gilts in both granulosa (31.7% and 22.6%, p < 0.001) and theca cell layers (34.8% and 20.2%, p < 0.001). This study indicated that apoptosis of the granulosa and theca cell layers in the follicles was more pronounced in the ovarian tissue of delayed puberty gilts than cyclic gilts. This implied that apoptosis could be used as a biologic marker for follicular development/function and also that apoptosis was significantly associated with anoestrus or delayed puberty in gilts, commonly observed in tropical climates.  相似文献   

5.
This study was performed to evaluate plasma concentrations of anti‐Mullerian hormone (AMH) and the ovarian antral follicle population (AFP) in different genetic groups. Cyclic heifers (13 Bubalus bubalis [Murrah]; 15 Bos taurus [Holstein] and 10 Bos indicus [Gyr]) were maintained under the same management and were synchronized with two doses of 150 μg IM d‐cloprostenol administered 14 days apart. After the second d‐cloprostenol treatment, heifers had their ovaries scanned daily by ultrasound to define the day of ovulation. On the same day, the AFP was determined and a plasma sample was collected to measure AMH. Murrah heifers had less AFP (25.6 ± 2.1 follicles; p = 0.01) and plasma AMH concentration (0.18 ± 0.03 ng/ml; p < 0.001) than Gyr (60.0 ± 12.2 follicles and 0.60 ± 0.12 ng/ml of AMH); however, data were similar when compared to Holstein (35.9 ± 6.8 follicles and 0.24 ± 0.06 ng/ml of AMH) heifers. Regardless of genetic background, there was a positive relationship between the AFP and plasmatic AMH concentration (Murrah [r = 0.62; p < 0.01], Holstein [r = 0.66; p < 0.001] and Gyr [r = 0.88; p < 0.001]). Also, when heifers were classified according to high‐ or low‐AMH concentration based on the average within each genetic group, high‐AMH heifers had greater (p < 0.0001) AFP than low‐AMH heifers. In conclusion, both Murrah and Holstein heifers presented lower plasma AMH concentration and AFP when compared to Gyr.  相似文献   

6.
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers.  相似文献   

7.
The pregnancy rates obtained after the transfer of cryopreserved in vitro‐produced (IVP) embryos are usually low and/or inconsistent. The objective of this study was to evaluate the pregnancy rates of Holstein, Gyr and Holstein × Gyr cattle after the transfer of vitrified IVP embryos produced with X‐sorted sperm. Seventy‐two Gyr and 703 Holstein females were subjected to ovum pickup (OPU) sessions, followed by in vitro embryo production using semen from sires of the same breeds. Embryos (1636 Holstein, 241 Gyr and 1515 Holstein × Gyr) were exposed to forskolin for 48 h prior to vitrification. The pregnancy rate achieved with Gyr dam and sire was 46.1%, which was similar (p = 0.11) to that of Holstein dam and Gyr sire (40.3%). Crossing Gyr dams with Holstein sires resulted in a pregnancy rate of 38.9% and did not differ (p = 0.58) from the pregnancy rate obtained with the cross between Holstein dams and Gyr sires. The rate obtained with Holstein dam and sire was 32.5%. The average pregnancy rate was 36.6%, and no difference was found in the proportion of female foetuses (88.8%, in average) among breeds (p > 0.05). In conclusion, transfer of cryopreserved X‐sorted embryos represents an interesting choice for dairy cattle. Despite the small differences between pregnancy rates, we highlight the efficiency of this strategy for all of the racial groups studied.  相似文献   

8.
This study evaluated the effects of follicular phase administration of TAK‐683, an investigational metastin/kisspeptin analog, on follicular growth, ovulation, luteal function and reproductive hormones in goats. After confirmation of ovulation by transrectal ultrasonography (Day 0), PGF2α (2 mg/head of dinoprost) was administered intramuscularly on Day 10 to induce luteal regression. At 12 h after PGF2α administration, intravenous administration of vehicle or 35 nmol (50 μg)/head of TAK‐683 was performed in control (n = 4) and treatment (n = 4) groups, respectively. Blood samples were collected at 6‐h intervals for 96 h and then daily until the detection of subsequent ovulation (second ovulation). After the second ovulation, ultrasound examinations and blood sampling were performed every other day or daily until the subsequent ovulation (third ovulation). Mean concentrations of LH and FSH in the treatment group were significantly higher 6 h after TAK‐683 treatment than those in the control group (12.0 ± 10.7 vs 1.0 ± 0.7 ng/ml for LH, 47.5 ± 28.2 vs 15.1 ± 3.4 ng/ml for FSH, p < 0.05), whereas mean concentrations of oestradiol in the treatment group decreased immediately after treatment (p < 0.05) as compared with the control group. Ovulation tended to be delayed (n = 2) or occurred early (n = 1) in the treatment group as compared with the control group. For the second ovulation, ovulatory follicles in the treatment group were significantly smaller in maximal diameter than in the control group (3.8 ± 0.5 vs 5.4 ± 0.2 mm, p < 0.05, n = 3). Administration of TAK‐683 in the follicular phase stimulates gonadotropin secretion and may have resulted in ovulation of premature follicles in goats.  相似文献   

9.
Very small follicles (<3.0 mm diameter) are over‐represented on the surface of ovaries of non‐cycling pigs, and the oocytes collected from these follicles generally have reduced developmental competence in vitro. This study examined the effect of follicle size on the nuclear maturation (n = 608), the potential of parthenogenetic activation (n = 243) and the cyclic AMP (cAMP) content of pre‐pubertal porcine oocytes (n = 480). In addition, the influence of follicle size on steroid hormone synthesis was analysed. Cumulus oocyte complexes (COCs) flushed from small (2.5–4.0 mm) or large (4.5–6.0 mm) ovarian follicles were cultured for 0, 28 and 46 h. After 46 h of IVM, a greater proportion of oocytes from 4.5‐ to 6.0‐mm follicles reach metaphase II (MII) compared with those from follicles with 2.5–4.0 mm of diameter (96.1 vs 77.0%, respectively; p < 0.001). Parthenogenetic activation of oocytes from large follicles produced higher developmental rates than oocytes from large follicles (p < 0.05). At 28 h, the IVM medium with oocytes from large follicles contained significantly more 17ß‐oestradiol (E2) than the medium with oocytes from small follicles (5.55 vs 3.45 ng/ml, respectively; p < 0.05) and at 46 h, the medium with oocytes from small follicles contained significantly more progesterone (P4) than the medium with oocytes from large follicles (276.7 vs 108.2 ng/ml, respectively, p < 0.05). Porcine oocytes from large follicles have higher nuclear and cytoplasmic maturation capacities, but the differences did not appear to be cAMP‐mediated. Our findings also suggest that COCs from small follicles undergo more intensive luteinization than COCs from large follicles. The results show that oocytes from follicles with a diameter greater than 4.0 mm are more suitable for in vitro studies.  相似文献   

10.
The variation in the kidding size of Black Bengal and Sirohi breed of goats makes them an interesting genetic material to study the underlying genetic mechanism of prolificacy. Accordingly, we studied the comparative ovarian morphometry including disparity in numbers of antral follicles of different sizes between these two breeds. Further, we evaluated the differential expression of the important candidate genes (viz., BMP15, GDF9 and BMPR1B) known to influence the ovulation rates and the prolificacy. The ovaries of Black Bengal (n = 20) goat were lighter (p < 0.01) in weight and smaller (p < 0.01) in diameter than those of Sirohi (n = 19) goats but possessed more numbers (p < 0.05) of corpus luteum (CL), large and small antral follicles. Quantitative real‐time PCR (RT‐qPCR) analysis revealed differential expression of mRNAs encoding for the BMP15 and GDF9. Small antral follicles of Black Bengal goats expressed 2.78‐fold more (p < 0.05) of BMP 15 than those of Sirohi goat. Expression of BMP15 (p < 0.01) and GDF9 (p < 0.05) mRNAs was more abundant in the small than the large antral follicles of Black Bengal goat. The more numbers of antral follicles per unit of ovarian mass and differential expression of BMP15 and GDF9 may serve as an important clue for higher prolificacy.  相似文献   

11.
The aim of this study was to evaluate the effect of leptin administration during superovulation on in vivo goat embryo production. Ten mature does were superovulated with 133 mg follicle‐stimulating hormone (FSH) i.m. in six descending doses at 12‐h intervals. The goats received 4.8 μg/kg human recombinant leptin s.c. (leptin group, n = 5) or phosphate‐buffered saline (PBS) (control group, n = 5) with the first and second FSH doses. The does were mated and subjected to embryo collection by transcervical technique 6 days later. The total number of cells per embryo and the number of cells with fragmented DNA were assessed in selected blastocysts by combining Hoechst 33342 and terminal dUTP nick‐end labelling (TUNEL) staining. Plasma concentrations of oestradiol (E2) and progesterone (P4) were determined by electrochemiluminescence from the day of FSH treatment, on the day of superovulatory oestrus and on the day before embryo collection. Compared with the control group, the does that received leptin had a higher number of transferable embryos (p < 0.005), fewer embryos classified as degenerated (p < 0.001) and fewer TUNEL‐positive cells/blastocyst (p < 0.001). The number of transferable embryos was positively correlated with E2 concentrations on day of oestrus (r = 0.562; p < 0.01) and P4 concentrations on the day of embryo collection (r = 0.912; p < 0.001). We concluded that in vivo leptin administration during FSH treatment improved embryo quality and affected ovarian steroidogenesis in superovulated goats.  相似文献   

12.
The aim of this study was to determine whether vitrification is an effective method when used for Japanese Black Cattle (Wagyu) in vivo‐derived embryos, collected following a superovulation treatment and embryo transfer (MOET) programme. In vivo‐derived morula and blastocysts collected on day 7 after artificial insemination, were vitrified using a modified droplet vitrification (MDV) procedure and subsequently warmed for transfer (ET) into synchronized recipients. Fresh embryos, and embryos cryopreserved using a standardized slow freezing procedure (direct thaw/direct transfer, DT) served as ET controls. Two different follicle‐stimulating hormone (FSH) sources, Folltropin® Canada (FSH BAH, 24 donors) and a brand prepared by the Chinese Academy of Science (FSH CAS, 16 donors), were compared in a series of superovulation outcomes following well‐established FSH administration protocols. Following data analysis, the total number of ovulations recorded at the time of embryo flushing (10.5 vs 8.5; p = 0.28) and the total number of transferable embryos (6.2 vs 5.1; p = 0.52) were similar between the two FSH sources. ET for MDV (39.7%, n = 78), DT (35.2%, n = 71) and fresh controls (47.1%, n = 34) resulted in similar pregnancy rates (p > 0.05). When MDV was used, a higher pregnancy rate (42.6%) resulted from the transfer of vitrified morulae, when compared to the DT counterparts (24.3%), (p = 0.05). Transfer of vitrified morulae resulted also in higher pregnancy rate, when compared to the transfer of vitrified blastocysts (42.6% vs. 29.4%; p < 0.05). Transfer of DT blastocysts resulted in higher pregnancy rate than morulae, similarly cryopreserved (47.1% vs. 24.3%, p < 0.05). In conclusion, MDV is an effective alternative methodology for cryopreservation of in vivo‐derived embryos. This study gives also indication that, compared to vitrified blastocysts, MDV of morula stage embryos results in higher pregnancy rates following warming and transfer into synchronized recipients.  相似文献   

13.
The occurrence of the pyometra is most common in the first half of the dioestrus when there is decreased cellular immunity associated with increased serum concentration of progesterone in females. The aim of this study was to determine the immunological profile of bitches with pyometra, studying serum levels of IL‐2, IL‐4, IL‐10, IFN‐γ, KC‐like and TNF‐α and comparing them with those of healthy bitches in anoestrus, dioestrus and pregnant. Forty females were divided into four experimental groups: group 1 (G1): with pyometra (n = 10); group 2 (G2): bitches in the second week of gestation (n = 10); group 3 (G3): in anoestrus (n = 10); and group 4 (G4): in dioestrus (n = 10). The serum levels for IL‐2, KC‐like, INF‐γ and TNF‐α were similar for all experimental groups. The values obtained for IL‐10 were found increased (p < 0.001) in animals in dioestrus and pyometra compared with females in anoestrus and pregnant, and the levels of IL‐4 observed were significantly greater (p < 0.001) in bitches with pyometra when compared with others. The cytokine profile in animals with pyometra is similar to bitches in dioestrus for IL‐10 and had increase in IL‐4 for bitches with pyometra, which represents an anti‐inflammatory these cases. This suggests the presence of an immunosuppressive state in both cases, which may explain the propensity of bitches in dioestrus to be affected by pyometra and the severity of the disease on these animals.  相似文献   

14.
The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows.  相似文献   

15.
The bovine embryonic signal interferon‐τ (IFN‐τ) produced by the trophoblast is known to pass through the uterine fluid towards the endometrium and further into the maternal blood, where IFN‐τ induces specific expression of interferon‐stimulated gene expression (ISG), for example in peripheral leucocytes. In sheep, it was shown experimentally by administration of IFN‐τ that ISG is also detectable in the liver. The objective was to test whether ISG can be detected in liver biopsy specimens from Holstein–Friesian heifers during early pregnancy. Liver biopsies were taken on day 18 from pregnant and non‐pregnant heifers (n = 19), and the interferon‐stimulated protein 15 kDa (ISG‐15) and myxovirus‐resistance protein‐1 (MX‐1) gene expression was detected. The expression of both MX‐1 (p: 24.33 ± 7.40 vs np: 9.00 ± 4.02) and ISG‐15 (p: 43.73 ± 23.22 vs 7.83 ± 3.63) was higher in pregnant compared to non‐pregnant heifers (p < 0.05). In conclusion, pregnancy induced ISG‐15 and MX‐1 gene expression in the liver already at day 18 in cattle.  相似文献   

16.
There are indications in the literature that delaying the period between ovarian superestimulation and ovum pick up (OPU) would induce follicles to a condition of initial atresia, which could be beneficial to oocyte development. In this work, we compared three protocols for OPU and in vitro production (IVP) of embryos, in Nellore cattle. Nellore cows (n = 18) were randomly allocated in three groups: Group 1 (OPU), Group 2 [Follicle stimulating hormone (FSH) and OPU] and Group 3 (FSH deprivation and OPU). Three OPUs were performed, and the animals were switched to a different group each time (crossover), in such a way that at the end of the experiment all cows received the 3 protocols. At random stage of the oestrous cycle (D‐2), all follicles ≥ 6 mm were aspirated to induce a new follicular wave 2 days afterwards (D0). In Group 1, OPU was performed on D2 and oocytes were processed to IVP. In Group 2, starting on D0, cows were superstimulated (FSH, Folltropin®, 30 mg administered daily, i.m., during three consecutive days, total dose = 180 mg), and 6 h after the last FSH dose, they received exogenous luteinizing hormone (LH) (12.5 mg, i.m., Lutropin®, D3). The OPU was performed 6 h after LH administration, i.e. 12 h after the last dose of FSH. Animals in Group 3 received the same treatment as those in Group 2, except that LH was administered 42 h after the last dose of FSH, and OPU occurred 6 h later. Therefore, in this group, follicles were deprived of FSH at 48 h. Both cleavage and blastocyst rates were similar (p > 0.05, anova ) among oocytes from Groups 1, 2 and 3, respectively: 77.4% (144/185) and 42.70% (79/185); 75.54% (105/139) and 31.65% (44/139); 63.52% (101/159) and 33.33% (53/159). However, hatched blastocyst rate was higher (p < 0.01) in Group 1 (30.27%, 56/185) when compared with Group 2 (11.51%, 16/139) or 3 (15.72%, 25/159). It is concluded that, contrary to previous work on European breeds (Bos taurus), ovarian superstimulation associated with deprivation of FSH and OPU (Group 3) did not increase IVP of Nellore embryos (Bos indicus). On the contrary, the highest hatched blastocyst rates were observed in oocytes from non‐superstimulated cows.  相似文献   

17.
The objective was to investigate the effects of reproductive seasonality on gamete quality in plains bison (Bison bison bison). Epididymal sperm (n = 61 per season), collected during the breeding season (July–September), had significantly higher post‐thaw total motility (36.76 ± 14.18 vs 31.24 ± 12.74%), and lower linearity (0.36 ± 0.06 vs 0.39 ± 0.04) and wobbliness (0.49 ± 0.04 vs 0.51 ± 0.03; mean ± SD) compared to non‐breeding season (January–March) samples. Representative samples (n = 4) from each season were used in heterologous IVF trials using cattle oocytes. Cleavage, morulae and blastocyst percentage were higher for breeding vs non‐breeding season sperm samples (81.88 ± 6.8 vs 49.94 ± 6.77; 41.89 ± 13.40 vs 27.08 ± 23.21; and 30.49 ± 17.87 vs 13.72 ± 18.98%, respectively). Plains bison ovaries collected during the breeding (n = 97 pairs) and non‐breeding (n = 100 pairs) seasons were classified as luteal or follicular. Oocytes recovered from these ovaries were classified into five grades based on morphology. There was no significant difference in the number of luteal ovaries or grades of oocytes recovered. Oocytes were matured, fertilized (with frozen sperm from three bison bulls) and cultured in vitro. Cleavage percentage was higher for oocytes collected during breeding vs non‐breeding season (83.72 ± 6.42 vs 73.98 ± 6.43), with no significant difference in subsequent development to blastocysts. In summary, epididymal sperm from non‐breeding season had decreased total motility and resulted in reduced embryo production in vitro. Oocytes collected during non‐breeding season had reduced ability to be matured, fertilized and/or undergo cleavage in vitro. Data suggested that season influenced gamete quality in plains bison.  相似文献   

18.
The goal of this study was to confirm the vasopressor and cardiac effects of POTENAY® INJETÁVEL (POT), a mephentermine‐based product, given to cattle with induced vascular/cardiac depression. Ten healthy Holstein cattle (206 ± 13 kg) followed a randomized‐complete‐block design (RCBD) utilizing crossover study design. Each animal randomly received (1 ml/25 kg, IM) of either POT (n = 10) or volume‐matched placebo control (0.9%NaCl, CP, n = 10). A subset of animals (n = 5) received POT first (day 0) while the remaining (n = 5) received CP; after a six‐day washout period, cattle received the opposite compound. Animals were anesthetized and catheterized for systemic/left ventricular hemodynamic monitoring. Myocardial dysfunction/hypotension was induced by increasing the end‐tidal isoflurane concentration until arterial blood pressure was 20% lower than at baseline and remained stable. Once the animal was determined to be hypotensive and hemodynamically stable, steady‐state hypotensive baseline data (BL2) were acquired, and treatment with either POT or CP was given. Data were acquired post‐treatment at every 15 min for 90 min. POT improved cardiac output (+68 L/min, ±14%, p < 0.05), MAP (+14 mmHg, ±4%, p < 0.05), HR (+22 bpm, ±8%, p < 0.05), and peak rates of ventricular pressure change during both systole (dP/dtmax: +37 mmHg/s ±13%, p < 0.05) and diastole (dP/dtmin: +31 mmHg/s, ±7%, p < 0.05). No improvements were noted following placebo‐control administration. Results indicate that POT improves cardiac performance and systemic hemodynamics in cattle with induced cardiovascular depression when given as single intramuscular injection.  相似文献   

19.
In this study, we examined the effects of superstimulation using follicle‐stimulating hormone (FSH) followed by gonadotropin‐releasing hormone (GnRH) on buffalo embryo production by ultrasound‐guided ovum pick‐up (OPU) and in vitro fertilization (IVF). Nine Murrah buffaloes were subjected to OPU‐IVF without superstimulation (control). The morphologies of the oocytes collected were evaluated, and oocytes were then submitted to in vitro maturation (IVM). Two days after OPU, same nine buffaloes were treated with twice‐daily injections of FSH for 3 days for superstimulation followed by a GnRH injection. Oocytes were collected by OPU 23–24 hr after the GnRH injection and submitted to IVM (the superstimulated group). The total number of follicles, number of follicles with a diameter > 8 mm, and number of oocytes surrounded by multi‐layered cumulus cells were higher in the superstimulated group than in the control group (p ≤ 0.05). After IVF, the percentages of cleavage and development to blastocysts were higher in the superstimulated group than in the control group (p < 0.05). In conclusion, superstimulation improved the quality of oocytes and the embryo productivity of OPU‐IVF in river buffaloes.  相似文献   

20.
Embryo production in donkeys is inefficient compared with that in other livestock. Obtaining a sufficient number of MII oocytes is the first step to solving this problem. In this study, the number, morphology and maturation rates of cumulus-oocyte complexes (COCs) obtained from abattoir-derived ovaries or live jennies were compared. The diameter of follicles from abattoir-derived ovaries was measured and divided into group 1 (2–6 mm), group 2 (6–10 mm), group 3 (10–20 mm), group 4 (20–28 mm) and group 5 (>28 mm). The results showed that the number of follicles per ovary in group 2 (3.6 ± 0.28) and 3 (4.2 ± 0.90) was higher than that in the other groups (p < .05). The recovery rate in group 3 was higher than group 1 (48.8% vs. 26.8%, p = .00), but lower than group 5 (48.8% vs. 76.5%, p = .025). The percentage of grade A COCs in group 3 was higher than group 2 (59.3% vs. 39.5%, p = .00) and group 1 (59.3% vs. 26.7%, p = .00). Moreover, the percentage of grade A COCs in group 4 (55.0%, p = .710) and group 5 (46.2%, p = .351) was reduced compared with that in group 3. From the above results, the developing follicles (group ovum pick-up [OPU], 10–20 mm) and preovulation follicles (group OPU-Preov, >35 mm) were aspirated from live jennies using OPU. Although there was no difference in the recovery rates of COCs between group 3 and OPU (48.8% vs. 43.0%, p = .184), the percentage of grades A COCs in group OPU was higher than group 3 (72.5% vs. 59.3%, p = .036). There was no difference in the maturation rate between group 3 and OPU (60.3% vs. 69.3%, p = .171) after the COCs matured in vitro. The rates of recovery (72.2%) and maturation (92.3%) in group OPU-Preov were higher than those in other groups (p < .05). Moreover, the effects of maturation time and serum type on maturation rates were evaluated in groups B44 (44 h, FBS), B36 (36 h, FBS) and D44 (44 h, foetal donkey serum, FDS). These results indicated that the maturation rate in group B36 was lower than group B44 (13.1% vs. 47.0%, p = .00) and group D44 (13.1% vs. 53.3%, p = .00). In conclusion, the quality of donkey COCs from OPU was higher than that from abattoir-derived ovaries, the suitable time of donkey in vitro maturation (IVM) was 44 h, and FBS could be replaced with FDS in donkey IVM medium.  相似文献   

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