117 Subclinical Mastitis Reduces Ovulation and Oocyte Quality in Milk-Producing Cows

2018 ◽  
Vol 30 (1) ◽  
pp. 198
Author(s):  
G. Santos ◽  
M. P. Bottino ◽  
M. B. D. Ferreira ◽  
J. C. Silveira ◽  
A. C. F. C. M. Avila ◽  
...  
Keyword(s):  
Follicular Fluid ◽  
Target Genes ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Subclinical Mastitis ◽  
Oocyte Quality ◽  
Ovulation Rate ◽  
Follicular Dynamics

The aim was to evaluate the effect of subclinical mastitis by somatic cell count (SCC) on follicular dynamics, ovulation, oocyte and cumulus cell quality, exosome size and concentration in milk-producing cows. Crossbred cows (Bos taurus × Bos indicus; that is, Holstein × Gyr) were randomly allocated to control (SCC <200,000 cells mL−1] and mastitis (SCC >400,000 cells mL−1) groups. In experiment 1 (follicular dynamics), cows (n = 57) were submitted to ultrasonographic evaluations every 24 h, after removal of an intravaginal progesterone device (Day 8) up to Day 10. From Day 10, ultrasound evaluations were performed every 12 h, until ovulation or until 96 h after progesterone device withdrawal, in order to follow final dominant follicle growth and ovulation. In experiment 2 (oocyte, cumulus cells, and follicular fluid evaluation), cows (n = 23) were submitted to follicular aspirations, preceded by synchronization of the emergence of the follicular wave. The levels of target genes in cumulus cells (BCL2, BAX, PI3K, PTEN, FOXO3) were evaluated by RT-qPCR. In the follicular fluid, the exosomes were isolated for evaluation of particle size. Data were analysed by the Glimmix procedure of SAS (SAS Institute Inc., Cary, NC, USA). Ovulation rate (P = 0.09) was higher in control cows [control 77.42% (24/31) and mastitis 57.69% (15/26)]. Viable oocyte rate (P = 0.01) was also higher in control cows [control 59.1% (130/220) and mastitis 41.9% (125/298)]. The dynamics of follicular growth did not differ between groups. The number of degenerate oocytes (P = 0.001) was higher in cows of the mastitis group. In the evaluation of cumulus cell gene expression, there was a higher abundance of BAX transcripts (P = 0.003) in cells of mastitis cows. Additionally, the mean and mode of exosome diameter in mastitis cows were smaller (P = 0.03 and P = 0.02, respectively). In conclusion, ovulation rate, oocyte quality, and follicular fluid exosome diameter were lower in cows with subclinical mastitis, demonstrating a link between mammary gland sanitary status and reproduction.

126 Interference of mastitis with ovulation and oocyte and granulosa cell quality in dairy cows

2019 ◽  
Vol 31 (1) ◽  
pp. 188
Author(s):  
G. Santos ◽  
M. P. Bottino ◽  
A. P. C. Santos ◽  
R. E. Orlandi ◽  
L. M. S. Simões ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Follicular Fluid ◽  
Rate Control ◽  
Cumulus Cell ◽  
Transcript Abundance ◽  
Cumulus Cells ◽  
Subclinical Mastitis ◽  
Oocyte Quality ◽  
Ovulation Rate ◽  
Intravaginal Device

The objective of this study was to evaluate the effect of mastitis diagnosed by somatic cell count (SCC) on follicular growth, ovulation, oocytes and cumulus cells quality and the concentration and size of exosomes in follicular fluid of dairy cows. In the study, crossbred cows (Bos taurus-Holstein×Bos indicus-Gir) were classified for analysis as control (SCC &lt;200.000 cells mL−1) and mastitis (SCC &gt;400.000 cells mL−1) groups. In Experiment 1 (follicular dynamics), cows (n=57: control=31; mastitis=26) received a progesterone intravaginal device (Sincrogest®, Ourofino Saude Animal, Cravinhos, Brazil) and 2mg of oestradiol benzoate (Sincrodiol®, Ourofino Saude Animal) injected IM. Eight days later (D8), the progesterone device was removed and cows received IM 500mg of cloprostenol (Sincrocio®, Ourofino Saude Animal), 1mg of oestradiol cypionate (SincroCP®, Ourofino Saude Animal) and 300IU of eCG (SicroeCG®, Ourofino Saude Animal). Ultrasound exams (Mindray 4900, probe linear de 5MHz, Shenzhen, China) were performed every 24h from removal of the progesterone-releasing intravaginal device (D8) until 48h later. Thereafter, evaluations were performed every 12h, until ovulation or up to 96h after removal of the progesterone-releasing intravaginal device. In Experiment 2 (oocyte, cumulus complexes, and follicular fluid evaluation), cows (n=26: control=13; mastitis=13) were submitted to follicular aspiration (ovum pickup) for oocyte quality and cumulus cells transcript evaluation. Transcript abundance of apoptosis markers (BCL2, BAX, PI3K, PTEN, FOXO3) was determined by real-time RT-PCR. Moreover, 7 days after the ovum pickup session, the dominant follicle was aspirated and follicular fluid samples were obtained. Exosomes were isolated from the follicular fluid by serial centrifugations, which were also performed for evaluation of particle size and concentration. Statistical analyses were performed using the SAS (SAS Institute Inc., Cary, NC, USA), and the GLIMMIX procedure was used to determine significant differences between groups. Gene expression and exosome data were submitted to the Student’s t-test. Ovulation rate [control 77.4% (24/31) and mastitis 57.7% (15/26); P=0.09] and viable oocytes rate [control 59.1% (130/220) and mastitis 41.9% (125/298); P=0.01] were higher in control animals. Additionally, there was a greater number of degenerate oocytes (control 6.7±1.2 and mastitis 13.3±5.5; P=0.001) in subclinical mastitis cows. There was greater abundance (P=0.003) of BAX cumulus cell transcripts and exosome mean (P=0.03) was smaller in subclinical mastitis cows. However, BCL2, PI3K, PTEN, nd FOXO3 cumulus cell transcripts was similar between treatments. In conclusion, ovulation rate, oocyte quality, and exosome diameter were smaller in cows with SCC &gt;400.000 cells mL−1, demonstrating that subclinical mastitis can influence the fertility of dairy cows.

154 Exosomes in Follicular Fluid Protect the Bovine Oocyte from Heat Shock

2018 ◽  
Vol 30 (1) ◽  
pp. 217 ◽  
Author(s):  
T. A. Rodrigues ◽  
A. Alli ◽  
F. F. Paula-Lopes ◽  
P. Hansen
Keyword(s):  
Heat Shock ◽  
Follicular Fluid ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Effect Of Temperature ◽  
Vehicle Group ◽  
Bovine Oocyte ◽  
Cleavage Rate

Elevated temperature can compromise the ability of the mammalian oocyte to develop to the blastocyst stage after fertilization. The microenvironment of the oocyte is determined by the cellular and non-cellular components of the follicle including cumulus cells and follicular fluid. Here we tested whether follicular fluid contains molecules that can protect the bovine oocyte from heat shock during maturation, and if so, whether some of these protective molecules are present in exosomes. The experiments utilised ovaries from Bos taurus and admixtures of B. taurus and Bos indicus. Four separate pools of follicular fluid were prepared by aspiration of follicles from 48 to 70 slaughterhouse ovaries. Exosomes were isolated from follicular fluid by a series of centrifugation, filtration, and ultracentrifugation steps before being reconstituted in PBS. Each of the 4 exosome preparations was subject to particle size and concentration analysis. The experiments were designed as 2 × 3 factorial to test the effect of temperature and supplementation. Cumulus-oocyte complexes (COC) obtained from slaughterhouse ovaries were matured at 38.5°C for 22 h (control) or 41°C for 14 h followed by 38.5°C for 8 h (heat shock). Maturation was performed in the presence of vehicle (PBS), 10% (v/v) follicular fluid, or exosomes (16 × 109 particles/mL). Data were analysed by least-squares ANOVA. Orthogonal contrasts and the mean separation test pdiff were used to compare means. Effects of treatment on cumulus cell expansion (change in diameter after maturation) were replicated 5 times using 119 to 122 COC per treatment. Effects of treatment on embryonic development after fertilization of treated COC was determined in 6 replicates using 244 to 286 embryos per replicate. Expansion was reduced by heat shock (P < 0.001), and affected by treatment (P < 0.05), with both follicular fluid and exosomes preventing the decrease in expansion caused by heat shock. Cleavage was reduced by heat shock (P < 0.001) and affected by treatment (P < 0.05) and the interaction between temperature × supplementation (P < 0.05). Although heat shock reduced the cleavage rate for vehicle-treated oocytes (77 v. 67%), there was no effect of heat shock for oocytes treated with follicular fluid FF (78 v. 74%) or exosomes (79 v. 78%; SEM = 1.4%). Heat shock also reduced the percent of cleaved embryos becoming blastocysts for the vehicle group (27 v. 17%; P < 0.05) but had no effect on percent of cleaved embryos becoming blastocysts for the follicular fluid (31% v. 26%) or exosome groups (28 v. 26%). Uptake of exosomes into isolated cumulus cells and oocytes cultured at 38.5°C for 0.5, 1, 14 and 22 h was examined using labelling of exosomes with 10 µM BODIPY® Ceramide TR (Thermo Fisher Scieintific, Waltham, MA, USA) and confocal microscopy. Exosomes were taken up by cumulus cells after culture for 1 h or later but were not taken up by oocytes. In conclusion, follicular fluid exosomes protected the oocytes from heat shock and this effect seems to be mediated by cumulus cells. Study supported by BARD US-4719-14.

scholarly journals Ovarian follicular dynamics, progesterone concentrations, pregnancy rates and transcriptional patterns in Bos indicus females with a high or low antral follicle count

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Marina Amaro de Lima ◽  
Fábio Morotti ◽  
Bernardo Marcozzi Bayeux ◽  
Rômulo Germano de Rezende ◽  
Ramon Cesar Botigelli ◽  
...  
Keyword(s):  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cells ◽  
Antral Follicle ◽  
Antral Follicle Count ◽  
Pregnancy Rates ◽  
Cellular Stress Response ◽  
Serum Progesterone ◽  
Epigenetic Modulation ◽  
Follicular Dynamics

Abstract We evaluated the effect of the antral follicle count (AFC) on ovarian follicular dynamics, pregnancy rates, progesterone concentrations, and transcriptional patterns of genes in Nelore cattle (Bos taurus indicus) after a timed artificial insemination (TAI) programme. Cows were separated based on the AFC, and those with a high AFC showed a larger (P < 0.0001) ovarian diameter and area than those with a very low AFC. Females with a very low AFC exhibited a larger (P < 0.01) diameter of the dominant follicle at TAI (13.6 ± 0.3 vs. 12.2 ± 0.4 mm) and a tendency (P = 0.06) to have different serum progesterone concentrations (2.9 ± 0.3 vs. 2.1 ± 0.3 ng/mL; on day 18, considering day 0 as the beginning of the synchronization protocol) than those with a high AFC. The pregnancy rate was higher (P ≤ 0.05) in animals with a very low (57.9%) and low (53.1%) AFC than in those with a high AFC (45.2%). The expression of genes related to intercellular communication, meiotic control, epigenetic modulation, cell division, follicular growth, cell maintenance, steroidogenesis and cellular stress response was assessed on day 5. In females with a low AFC, 8 and 21 genes in oocytes and cumulus cells, respectively, were upregulated (P < 0.05), while 3 and 6 genes in oocytes and cumulus cells, respectively, were downregulated. The results described here will help elucidate the differences in ovarian physiology and the reproductive success of Bos indicus females with a low or high AFC.

The follicular microenvironment in low (++) and high (I+B+) ovulation rate ewes

Reproduction ◽  
2020 ◽  
Vol 159 (5) ◽  
pp. 585-599
Author(s):  
Zaramasina L Clark ◽  
Derek A Heath ◽  
Anne R O’Connell ◽  
Jennifer L Juengel ◽  
Kenneth P McNatty ◽  
...  
Keyword(s):  
Follicular Fluid ◽  
Cumulus Cell ◽  
Single Copy ◽  
Oocyte Quality ◽  
Ovulation Rate ◽  
Fluid Composition ◽  
Embryo Survival ◽  
Expression Levels ◽  
Follicular Maturation ◽  
Metabolic Substrates

Ewes with single copy mutations in GDF9, BMP15 or BMPR1B have smaller preovulatory follicles containing fewer granulosa cells (GC), while developmental competency of the oocyte appears to be maintained. We hypothesised that similarities and/or differences in follicular maturation events between WT (++) ewes and mutant ewes with single copy mutations in BMP15 and BMPR1B (I+B+) are key to the attainment of oocyte developmental competency and for increasing ovulation rate (OR) without compromising oocyte quality. Developmental competency of oocytes from I+B+ animals was confirmed following embryo transfer to recipient ewes. The microenvironment of both growing and presumptive preovulatory (PPOV) follicles from ++ and I+B+ ewes was investigated. When grouped according to gonadotropin-responsiveness, PPOV follicles from I+B+ ewes had smaller mean diameters with fewer GC than equivalent follicles in ++ ewes (OR = 4.4 ± 0.7 and 1.7 ± 0.2, respectively; P < 0.001). Functional differences between these genotypes included differential gonadotropin-responsiveness of GC, follicular fluid composition and expression levels of cumulus cell-derived VCAN, PGR, EREG and BMPR2 genes. A unique microenvironment was characterised in I+B+ follicles as they underwent maturation. Our evidence suggests that GC were less metabolically active, resulting in increased follicular fluid concentrations of amino acids and metabolic substrates, potentially protecting the oocyte from ROS. Normal expression levels of key genes linked to oocyte quality and embryo survival in I+B+ follicles support the successful lambing percentage of transferred I+B+ oocytes. In conclusion, these I+B+ oocytes develop normally, despite radical changes in follicular size and GC number induced by these combined heterozygous mutations.

P–219 mtDNA content in bovine cumulus cells does not predict oocytés developmental competence

2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Á Martíne. Moro ◽  
I Lamas-Toranzo ◽  
L González-Brusi ◽  
A Pérez-Gómez ◽  
P Bermejo-Álvarez
Keyword(s):  
Cumulus Cell ◽  
Cumulus Cells ◽  
Oocyte Quality ◽  
Blastocyst Stage ◽  
Early Embryo ◽  
Developmental Competence ◽  
Success Rates ◽  
Developmental Potential ◽  
Mtdna Sequence

Abstract Study question Does cumulus cell mtDNA content correlate with oocyte developmental potential in the bovine model? Summary answer The relative amount of mtDNA content did not vary significantly in oocytes showing different developmental outcomes following IVF What is known already Cumulus cells are closely connected to the oocyte through transzonal projections, serving essential metabolic functions during folliculogenesis. These oocyte-supporting cells are removed and discarded prior to ICSI, thereby constituting an interesting biological material on which to perform molecular analysis aimed to predict oocyte developmental competence. Previous studies have positively associated oocytés mtDNA content with developmental potential in both animal models and women. However, it remains debatable whether mtDNA content in cumulus cells could be used as a proxy to infer oocyte developmental potential. Study design, size, duration Bovine cumulus cells were allocated into three groups according to the developmental potential of the oocyte: 1) oocytes developing to blastocysts following IVF (Bl+Cl+), 2) oocytes cleaving following IVF but arresting their development prior to the blastocyst stage (Bl-Cl+), and 3) oocytes not cleaving following IVF (Bl-Cl-). Relative mtDNA content was analysed in 40 samples/group, each composed by the cumulus cells from one cumulus-oocyte complex (COC). Participants/materials, setting, methods Bovine cumulus-oocyte complexes were obtained from slaughtered cattle and individually matured in vitro (IVM). Following IVM, cumulus cells were removed by hyaluronidase treatment, pelleted, snap frozen in liquid nitrogen and stored at –80 ºC until analysis. Cumulus-free oocytes were fertilized and cultured in vitro individually and development was recorded for each oocyte. Relative mtDNA abundance was determined by qPCR, amplifying a mtDNA sequence (COX1) and a chromosomal sequence (PPIA). Statistical differences were tested by ANOVA. Main results and the role of chance Relative mtDNA abundance did not differ significantly (ANOVA p &gt; 0.05) between the three groups exhibiting different developmental potential (1±0.06 vs. 1.19±0.05 vs. 1.11±0.05, for Bl+Cl+ vs. Bl-Cl+ vs. Bl-Cl-, mean±s.e.m.). Limitations, reasons for caution Experiments were conducted in the bovine model. Although bovine folliculogenesis, monoovulatory ovulation and early embryo development exhibit considerable similarities with that of humans, caution should be taken when extrapolating these data to humans. Wider implications of the findings: The use of molecular markers for oocyte developmental potential in cumulus cells could be used to enhance success rates following single-embryo transfer. Unfortunately, mtDNA in cumulus cells was not found to be a good proxy for oocyte quality. Trial registration number Not applicable

scholarly journals Predictive value of bovine follicular components as markers of oocyte developmental potential

2014 ◽  
Vol 26 (2) ◽  
pp. 337 ◽  
Author(s):  
Satoko Matoba ◽  
Katrin Bender ◽  
Alan G. Fahey ◽  
Solomon Mamo ◽  
Lorraine Brennan ◽  
...  
Keyword(s):  
Follicular Fluid ◽  
Cumulus Cell ◽  
Principal Component ◽  
Transcript Abundance ◽  
Cumulus Cells ◽  
Blastocyst Stage ◽  
Developmental Potential ◽  
Thecal Cells ◽  
Total Fatty Acids

The follicle is a unique micro-environment within which the oocyte can develop and mature to a fertilisable gamete. The aim of this study was to investigate the ability of a panel of follicular parameters, including intrafollicular steroid and metabolomic profiles and theca, granulosa and cumulus cell candidate gene mRNA abundance, to predict the potential of bovine oocytes to develop to the blastocyst stage in vitro. Individual follicles were dissected from abattoir ovaries, carefully ruptured under a stereomicroscope and the oocyte was recovered and individually processed through in vitro maturation, fertilisation and culture. The mean (± s.e.m.) follicular concentrations of testosterone (62.8 ± 4.8 ng mL–1), progesterone (616.8 ± 31.9 ng mL–1) and oestradiol (14.4 ± 2.4 ng mL–1) were not different (P > 0.05) between oocytes that formed (competent) or failed to form (incompetent) blastocysts. Principal-component analysis of the quantified aqueous metabolites in follicular fluid showed differences between oocytes that formed blastocysts and oocytes that degenerated; l-alanine, glycine and l-glutamate were positively correlated and urea was negatively correlated with blastocyst formation. Follicular fluid associated with competent oocytes was significantly lower in palmitic acid (P = 0.023) and total fatty acids (P = 0.031) and significantly higher in linolenic acid (P = 0.036) than follicular fluid from incompetent oocytes. Significantly higher (P < 0.05) transcript abundance of LHCGR in granulosa cells, ESR1 and VCAN in thecal cells and TNFAIP6 in cumulus cells was associated with competent compared with incompetent oocytes.

273 OVUM PICKUP AT DIFFERENT TIMES OF A SYNCHRONIZED FOLLICULAR WAVE DID NOT AFFECT IVP IN BOS INDICUS, BOS TAURUS, OR BUBALUS BUBALIS

2010 ◽  
Vol 22 (1) ◽  
pp. 293 ◽  
Author(s):  
L. U. Gimenes ◽  
M. L. Ferraz ◽  
A. Araujo ◽  
P. Fantinato Neto ◽  
M. R. Chiarati ◽  
...  
Keyword(s):  
Mixed Model ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cell ◽  
Bubalus Bubalis ◽  
Genetic Group ◽  
Cleavage Rate ◽  
Follicular Wave ◽  
Counting Data ◽  
Initial Hypothesis

One important factor in the success of ovum pickup (OPU)/IVP in Bos taurus is the follicular status at OPU concerning the dominance period (Hendriksen et al. 2000 Theriogenology 53, 11-20). The hypothesis of the present study is that OPU performed after follicle deviation, when follicles show a mild level of atresia, improves competence for IVP in Nelore (NE), Holstein (HO), and buffaloes (BU). Objectives were to determine effects of OPU done at different times of synchronized follicular wave (1, 3, or 5 d after expected emergence) and of genetic group (NE, HO, and BU) on IVP. A total of 27 heifers (9 of each genetic group) were maintained in contemporary nutritional and environmental conditions during experiment, in a cross-over design, performed in 6 replicates. Recovered oocytes with at least one cumulus cell layer were matured in TCM-199 supplemented with 10% of FCS plus 50 μM of cysteamin and 0.3 mM of cystine, at 38.5°C with 5% CO2 in air for 24 h. IVF was done with 2 × 106 spermatozoa per mL of NE (for bovine oocytes) or BU semen (for BU oocytes), for 20 h at the same incubator conditions of IVM. After IVF, presumptive zygotes were denuded and cultured in SOF under the same previous atmosphere conditions. Medium was changed 3 d after IVF when cleavage rate (CR) was assessed. Blastocyst (BR) and hatching rates (HR) were evaluated 7 and 9 days after IVF, respectively. About 50% of hatched blastocysts were fixed until nuclei counting. Data were analyzed by ANOVA using the Proc Mixed model. No effects of interaction or time of synchronization were observed in any of the variables. Concerning genetic group, NE had better results than HO and BU (mean ± SEM / heifer / replicate), respectively, for visualized follicles (41.0a ± 2.1, 22.1b ± 1.3, 18.8b ± 0.9), total oocytes (37.1a ± 2.5, 15.4b ± 1.2, 14.8b ± 1.0), oocytes at IVM (30.8a ± 2.4, 10.7b ± 1.0, 7.9b ± 0.7), oocytes at IVC (18.7a ± 0.8, 8.0b ± 0.5, 7.5b ± 0.4), cleaved embryos (15.4a ± 0.7, 4.6b ± 0.4, 4.4b ± 0.3),CR(81.8a, 59.1b, 62.3b), blastocysts on Day 7 (5.1a ± 0.6, 1.0b ± 0.2, 0.6b ± 0.1), BR (25.8a, 13.6b, 9.1b), and hatched blastocysts on Day 9 (2.6a ± 0.4, 0.3b ± 0.1, 0.3b ± 0.1). Recovery rate and HR were greater for NE (89.4 and 50.6%, respectively) than for HO (73.3 and 23.2%), but neither differed from BU (82.8 and 31.9%). Also, the percentage of viable was greater for NE (83.0) than for HO (66.9) and BU (53.1). No effects were observed for nuclei counting (NE = 176.6 ± 5.3, HO = 168.9 ± 13.7 and BU = 206.1 ± 23.1). Results demonstrate that Nelore had a better efficiency for IVP than Holstein and buffaloes. OPU performed at different times of synchronized follicular wave did not influence IVP, conversely to the initial hypothesis of this study. FAPESP (06/59550-6, 07/04782-2), Tortuga Cia Zootecnica®, Santa Adele and São Caetano Farms, LMMD, PCAPS, HOVET (Dr. Ubiraem Schalch), VRA, VNP (Prof. Dr. Francisco de Palma Rennó).

205 CUMULUS CELL MORPHOLOGY BEFORE AND AFTER IN VITRO MATURATION AS AN INDICATOR OF PORCINE OOCYTE DEVELOPMENTAL COMPETENCE

2010 ◽  
Vol 22 (1) ◽  
pp. 260
Author(s):  
M. Bertoldo ◽  
P. K. Holyoake ◽  
G. Evans ◽  
C. G. Grupen
Keyword(s):  
Cell Morphology ◽  
In Vitro Maturation ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Oocyte Quality ◽  
Developmental Competence ◽  
Oocyte Developmental Competence ◽  
Before And After ◽  
Follicle Size

Effective in vitro maturation (IVM) is essential for successful in vitro embryo production. The morphology of the cumulus investment before and after IVM may be a useful noninvasive indicator of oocyte quality. In pigs, oocyte developmental competence is reduced during the summer months. The aim of this study was to determine whether the morphology of cumulus-oocyte complexes (COC) before and after IVM are associated with oocyte quality, using COC collected from small and large follicles in summer and winter as models of poor and good oocyte quality. Ovaries were collected from sows slaughtered 4 days after weaning. The COC recovered from small (3-4 mm) and large (5-8 mm) antral follicles were morphologically graded and parthenogenetically activated following IVM during winter (n = 1419; 10 replicates) and summer (n = 2803; 10 replicates). Grade 1 and 2 COC had >2 layers of compact cumulus cells and a homogenous cytoplasm. Grade 3 COC were either partially or fully denuded, had a heterogeneous cytoplasm, or were vacuolated or dark in color. Grade 4 COC had expanded cumulus cells. Cumulus expansion was also assessed subsequent to IVM. The COC recorded as having a cumulus expansion index (CEI) of 1 had the poorest expansion with no detectable response to IVM, whereas those with a CEI of 4 had the greatest amount of expansion, including that of the corona radiata. Data were analyzed using a generalized linear mixed model in GenStat® (release 10, VSN International, Hemel Hempstead, UK). There was an effect of follicle size for Grade 1 COC, with COC from large follicles in both seasons yielding better quality COC (P < 0.05). The proportion of COC in Grade 2 was higher in small follicles during winter compared with large follicles, but there were no differences between follicle sizes during summer (P < 0.05). The proportion of COC with CEI 1 was highest in COC from small follicles during summer (P < 0.05). The proportion of COC from large follicles with CEI 2 was higher during summer compared with winter (P < 0.05). There were no seasonal or follicle size effects on COC with CEI 3 or 4 (P > 0.05). The proportion of oocytes that developed to blastocysts was greater in winter than in summer (39.06% ± 5.67 v. 22.27% ± 4.01; P < 0.05). Oocytes derived from large follicles had a greater ability to form blastocysts compared with those from small follicles (37.13% ± 5.65 v. 23.32% ± 4.56; P < 0.06). Morphological assessment of cumulus cells before and after IVM may be a useful tool to evaluate the effects of follicle size on oocyte developmental competence. However, the results of the present study indicate that cumulus cell morphology is not a good indicator of the effect of season on oocyte developmental competence.

179 COMPARISON OF OOCYTE AND EMBRYO PRODUCTION AMONG BOS TAURUS, BOS INDICUS, AND INDICUS-TAURUS DONOR COWS

2010 ◽  
Vol 22 (1) ◽  
pp. 248 ◽  
Author(s):  
J. H. F. Pontes ◽  
K. C. F. Silva ◽  
A. C. Basso ◽  
C. R. Ferreira ◽  
G. M. G. Santos ◽  
...  
Keyword(s):  
High Efficiency ◽  
Bos Taurus ◽  
Bos Indicus ◽  
Cumulus Cells ◽  
Holstein Cows ◽  
Embryo Production ◽  
Total N ◽  
The Mean ◽  
Donor Cows

In recent years, Brazil has become the leading country in the world for the number of embryos produced in vitro (Thibier M 2009 IETS Embryo Transfer Newsletter 22, 12-19). This is partly due to the large numbers of Bos indicus animals in Brazil, making up about 80% of the total cattle. The mean oocyte production per ultrasound-guided follicular aspiration from Bos indicus is higher than those for European breeds (Pontes JHF et al. 2009 Theriogenology 71, 690-697). In the present study, we analyzed 5407 ovum pick ups (OPU) and compared the average production of total (n = 90,086) and viable (n = 64,826) oocytes and the number of embryos produced in vitro from Gir (Bos taurus indicus), Holstein (Bos taurus taurus), 1/4 Holstein × 3/4 Gir, and 1/2 Holstein-Gir crossbreed cows. To obtain oocytes, OPU was repeated from 4 to 7 times (mean = 5.7 ± 2.4) in each donor cow aged from 3 to 7 years (mean = 5.0 ± 2.3) during a 12-mo period. COCs (n = 90,086) obtained were classified according to the presence of cumulus cells and the oocyte cytoplasm aspect (homogeneous or heterogeneous/fragmented). The viable oocytes (n = 64,826) were in vitro matured for 24 h at 38.8°C in an atmosphere of 5% CO2 in air. Since this was a commercial programm, frozen sexed semen (2 × 106 mL-1) from Gir (n = 8) or Holstein (n = 7) sires previously tested for high efficiency was used for IVF. Fertilization was carried out (18-20 h) and the presumed embryos were cultured for 7 days in the same conditions as were used for IVM. Data were analyzed by ANOVA. On average, 16.7 ± 6.2 oocytes were obtained per OPU/IVF procedure and 71.96% were considered viable. The mean numbers of total oocytes per OPU/IVF procedure were 17.1 ± 4.4 for Gir cows (n = 617), 11.4 ± 3.9 for Holstein cows (n = 180), 20.4 ± 5.8 for 1/4 Holstein × 3/4 Gir (n = 44), and 31.4 ± 5.6 for 1/2 Holstein-Gir crossbreed females (n = 37, P < 0.01). The mean numbers of viable oocytes per OPU/IVF procedure were 12.1 ± 3.8 for Gir cows, 8.0 ± 2.6 for Holstein cows, 16.8, ± 5.0 for 1/4 Holstein × 3/4 Gir, and 24.3 ± 4.7 for 1/2 Holstein-Gir crossbreed females (P < 0.01). The average number of embryos produced by OPU/IVF were 3.2 (n = 12,243/3378) for Gir cows, 2.2 (n = 2426/1138) for Holstein cows, 3.9 (n = 1033/267) for 1/4 Holstein × 3/4 Gir, and 5.5 (n = 1222/224) for 1/2 Holstein-Gir. The average number of embryos produced per IVF session from 1/2 taurus × indicus donor cows was greater (P < 0.01) than from Bos indicus cows. The number of recoverable and viable oocytes and the number of embryos produced in vitro from Bos indicus donors were higher than from Bos taurus females. Therefore, the highest oocyte yield and the greatest embryo production were obtained from 1/2 taurus × indicus females. This work was supported by In Vitro Brasil.

scholarly journals Sequential exposure of porcine cumulus cells to FSH and/or LH is critical for appropriate expression of steroidogenic and ovulation-related genes that impact oocyte maturation in vivo and in vitro

Reproduction ◽  
2008 ◽  
Vol 136 (1) ◽  
pp. 9-21 ◽  
Author(s):  
Ikkou Kawashima ◽  
Tetsuji Okazaki ◽  
Noritaka Noma ◽  
Masahide Nishibori ◽  
Yasuhisa Yamashita ◽  
...  
Keyword(s):  
Oocyte Maturation ◽  
Chorionic Gonadotropin ◽  
Follicular Fluid ◽  
Culture System ◽  
Expression Patterns ◽  
Cumulus Cell ◽  
Cumulus Cells ◽  
Developmental Competence ◽  
Antral Follicles

In this study, we collected follicular fluid, granulosa cells, and cumulus cells from antral follicles at specific time intervals following equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG) treatment of gilts. The treatment with eCG increased the production of estrogen coordinately with up-regulated proliferation of granulosa and cumulus cells. eCG also induced the expression ofLHCGRandPGRin cumulus cells and progesterone accumulation was detected in follicular fluid prior to the LH/hCG surge. Moreover, progesterone and progesterone receptor (PGR) were critical for FSH-inducedLHCGRexpression in cumulus cells in culture. The expression ofLHCGRmRNA in cumulus cells was associated with the ability of LH to induce prostaglandin production, release of epidermal growth factor (EGF)-like factors, and a disintegrin and metalloprotease with thrombospondin-like repeats 1 expression, promoting cumulus cell oocyte complexes (COCs) expansion and oocyte maturation. Based on the unique expression and regulation ofPGRandLHCGRin cumulus cells, we designed a novel porcine COCs culture system in which hormones were added sequentially to mimic changes observedin vivo. Specifically, COCs from small antral follicles were pre-cultured with FSH and estradiol for 10 h at which time progesterone was added for another 10 h. After 20 h, COCs were moved to fresh medium containing LH, EGF, and progesterone. The oocytes matured in this revised COC culture system exhibited greater developmental competence to blastocyst stage. From these results, we conclude that to achieve optimal COC expansion and oocyte maturation in culture the unique gene expression patterns in cumulus cells of each species need to be characterized and used to increase the effectiveness of hormone stimulation.

Sign in / Sign up

Export Citation Format

Share Document