scholarly journals Thickness of cumulus cell layer is a significant factor in meiotic competence of buffalo oocytes

2004 ◽  
Vol 5 (3) ◽  
pp. 247 ◽  
Author(s):  
Hassan M Warriach ◽  
Kazim R Chohan
2021 ◽  
Vol 33 (2) ◽  
pp. 174
Author(s):  
K. M. Honneysett ◽  
M. L. Mphaphathi ◽  
A. M. Maqhashu ◽  
E. C. Webb

Oocyte recovery is a reproductive technology that can be done by using two techniques, aspiration and slicing. Invitro maturation (IVM) is an additional reproductive technology used to advance an oocyte to a maturation stage; thereafter, it may be used during IVF. The objectives of the present study were (1) to compare two different oocyte retrieval methods (aspiration and slicing) from pig ovaries on oocyte quality and quantity, and (2) to compare three different IVM media [NCSU 37, TCM-199, and modified porcine follicular fluid (mpFF=porcine follicular fluid+FSH+LH] on oocytes’ polar body extrusion. During aspiration, an 18G needle was attached to a 10-mL syringe and all visible follicles were aspirated. During slicing, a surgical blade was used to slice the ovaries held in mDPBS. Follicular fluid collected from both methods was assessed for the presence of oocytes with the aid of a microscope. The collected oocytes were then categorized as Grade A, B, or C: Grade A=oocytes with compacted, multilayered cumulus cells and a homogeneous ooplasm; Grade B=oocytes with a compact cumulus cell layer with homogeneous ooplasm; Grade C=oocytes with a less compact cumulus cell layer with irregular ooplasm containing dark granules. The IVM media were placed in a four-well multidish; thereafter Grades A and B oocytes were allocated per treatment groups and matured for 44h. The treatment means were compared using the Fisher’s protected t-test least significant difference. The results showed significant differences between the grades of oocytes (P<0.05) with Grade A and B oocytes accounting for 50.8% of total oocytes (193.8) for aspiration and 58.7% of total oocytes (488.6) for slicing. The oocytes polar body extrusion was recorded as 25.3, 84.2, and 73.8% for NCSU 37 (P<0.05) and TCM-199 and mpFF respectively (P>0.05). In conclusion, the slicing method proved to be better than aspiration with regards to the retrieval of Grades A and B oocytes as well as the total number of oocytes retrieved. The TCM-199 and mpFF media had a higher percentage of oocytes with polar body extrusion than NCSU 37.


2017 ◽  
Vol 29 (1) ◽  
pp. 151
Author(s):  
L. Cai ◽  
E. O. Park ◽  
Y.-X. Jin ◽  
K.-C. Hwang ◽  
Y. W. Jeong ◽  
...  

Although several cloned pigs have been successfully produced, the developmental competence of cloned embryos in vitro is still very low. Granulocyte colony-stimulating factor receptor (G-CSFR) was founded in the human trophoblastic cell line that is implicated in regulation and proliferation of trophoblast. In the present study, the somatic cell NT embryos derived from oocytes that have more than 3 cumulus cells layer were cultured and supplemented with various concentrations of hrG-CSF (0, 10, 50, and 100 ng mL−1, respectively). Although there were no significant effects on the various concentration of hrG-CSF treatment groups compared with control, the somatic cell NT blastocysts formation tended to increase after 10 ng mL−1 hrG-CSF treatment (24.19 ± 2.90%) compared with control (21.37 ± 2.98%). Moreover, we investigated the effects of 10 ng mL−1 hrG-CSF on in vitro culture of porcine cloned embryos derived from oocytes that were categorized into grade A (cumulus cell layer >10), grade B (10 > cumulus cell layer ≥ 3), and grade C (cumulus cell layer <3). After supplementation of 10 ng mL−1 hrG-CSF on in vitro-culture of different groups, the developmental competence, blastocyst quality, and gene transcript levels were observed. The results showed that 10 ng mL−1 hrG-CSF has no beneficial effects on cloned embryos derived from grade A oocytes (10 ng mL−1 hrG-CSF 25.35 ± 2.53% v. control 25.00 ± 2.66%), but it significantly increased blastocyst formation of embryos derived from grade B oocytes (22.09 ± 2.10%) compared with grade B control (12.09 ± 2.31%, P < 0.05). There were obvious increases in blastocyst formation derived from grade C oocytes after 10 ng mL−1 hrG-SCF treatment (25.74 ± 1.65%) compared with grade C control (16.82 ± 2.30%, P < 0.05). However, there were no significantly differences in cleavage rate and total cell number of blastocysts among each group. Otherwise, the PCNA, POU5F1, Dnmt1, Bcl2, and Bax transcript levels were significantly increased in blastocysts that were derived from grade C oocytes after 10 ng mL−1 hrG-SCF treatment compared with grade C control. In conclusion, supplementation of 10 ng mL−1 hrG-CSF in in vitro-cultured porcine embryos increased blastocyst formation of embryos derived from thin cumulus layer of oocytes by reducing apoptosis while increasing cell proliferation and nuclear reprogramming. These results provide an experimental basis for the use of poor quality oocytes for agricultural production. This work was supported by a grant from Research Program (No. 307–02) Gyeonggi-province project and the Next-Generation BioGreen21 Program [no. PJ01107702], Rural Developmental Administration (RDA), Republic of Korea.


2015 ◽  
Vol 92 (1) ◽  
Author(s):  
Francesca Lolicato ◽  
Jos F. Brouwers ◽  
Chris H.A. van de Lest ◽  
Richard Wubbolts ◽  
Hilde Aardema ◽  
...  
Keyword(s):  

1994 ◽  
Vol 125 (5) ◽  
pp. 1157-1163 ◽  
Author(s):  
Y Lin ◽  
K Mahan ◽  
W F Lathrop ◽  
D G Myles ◽  
P Primakoff

A typical mammalian egg is surrounded by an outer layer of about 3,000 cumulus cells embedded in an extracellular matrix rich in hyaluronic acid. A current, widely proposed model is that the fertilizing sperm, while it is acrosome intact, passes through the cumulus cell layer and binds to the egg zona pellucida. This current model lacks a well-supported explanation for how sperm penetrate the cumulus layer. We report that the sperm protein PH-20 has a hyaluronidase activity and is present on the plasma membrane of mouse and human sperm. Brief treatment with purified, recombinant PH-20 can release all the cumulus cells surrounding mouse eggs. Acrosome intact mouse sperm incubated with anti-PH-20 antibodies can not pass through the cumulus layer and thus can not reach the zona pellucida. These results, indicating that PH-20 enables acrosome intact sperm to penetrate the cumulus barrier, reveal a mechanism for cumulus penetration, and thus provide the missing element in the current model.


Author(s):  
Waykin Nopanitaya ◽  
Joe W. Grisham ◽  
Johnny L. Carson

An interesting feature of the goldfish liver is the morphology of the hepatic plate, which is always formed by a two-cell layer of hepatocytes. Hepatic plates of the goldfish liver contain an infrequently seen second type of cell, in the centers of plates between two hepatocytes. A TEH study by Yamamoto (1) demonstrated ultrastructural differences between hepatocytes and centrally located cells in hepatic plates; the latter were classified as ductule cells of the biliary system. None of the previous studies clearly showed a three-dimensional organization of the two cell types described. In the present investigation we utilize SEM to elucidate the arrangement of hepatocytes and bile ductular cells in intralobular plates of goldfish liver.Livers from young goldfish (Carassius auratus), about 6-10 cm, fed commercial fish food were used for this study. Hepatic samples were fixed in 4% buffered paraformaldehyde, cut into pieces, fractured, osmicated, CPD, mounted Au-Pd coated, and viewed by SEM at 17-20 kV. Our observations were confined to the ultrastructure of biliary passages within intralobular plates, ductule cells, and hepatocytes.


Author(s):  
A. Trillo

There are conflicting reports regarding some fine structural details of arteries from several animal species. Buck denied the existence of a sub-endothelial space, while Karrer and Keech described a space of variable width which separates the endothelium from the underlying internal elastic lamina in aortas of aging rats and mice respectively.The present communication deals with the ultrastrueture of the interface between the endothelial cell layer and the internal elastic lamina as observed in carotid arteries from rabbits of varying ages.


Author(s):  
Maria Anna Pabst

In addition to the compound eyes, honeybees have three dorsal ocelli on the vertex of the head. Each ocellus has about 800 elongated photoreceptor cells. They are paired and the distal segment of each pair bears densely packed microvilli forming together a platelike fused rhabdom. Beneath a common cuticular lens a single layer of corneagenous cells is present.Ultrastructural studies were made of the retina of praepupae, different pupal stages and adult worker bees by thin sections and freeze-etch preparations. In praepupae the ocellar anlage consists of a conical group of epidermal cells that differentiate to photoreceptor cells, glial cells and corneagenous cells. Some photoreceptor cells are already paired and show disarrayed microvilli with circularly ordered filaments inside. In ocelli of 2-day-old pupae, when a retinogenous and a lentinogenous cell layer can be clearly distinguished, cell membranes of the distal part of two photoreceptor cells begin to interdigitate with each other and so start to form the definitive microvilli. At the beginning the microvilli often occupy the whole width of the developing rhabdom (Fig. 1).


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