Browsing by Author "Ghanem, Nasser"

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Effect of Heat Stress on Developmental Competence of In Vitro Matured Oocytes of Camelus Dromedaries with Different Qualities
(Scienceline Publication, 44190) Ashour, G; El-Sayed, Ashraf; Khalifa, M; Ghanem, Nasser
The deleterious effect of heat stress on cumulus-oocytes complexes (COCs) competence is well recognized in different livestock species. Therefore, the present study aimed to investigate the effect of physiologically relevant heat stress on the developmental competence of camel COCs during in vitro maturation (IVM). A total of 1548 COCs were divided into six groups in this study. The groups were named K1 and K2 representing good and low-quality COCs incubated at 38.5oC for 30 hours. While K3 and k4 represent good and low-quality COCs exposed to 41oC for the first 6 hours of IVM. Finally, K5 and k6 represent the groups of good and low-quality COCs exposed to 42oC for the first 6 hours of IVM. After exposure of COCs to heat stress at 41°C and 42°C during the first 6 hours of in vitro maturation, the COCs were incubated at 38.5°C for 24 hours of IVM. The in vitro matured COCs were activated to cleave using ethanol followed by 4 mM 6-DMAP and developed embryos were cultured in vitro for 7 days post parthenogenetic activation. The results of this study indicated that heat stress at 42oC significantly decreased the Pb (polar body) extrusion rate in K4 and K6, compared to other groups. Additionally, the embryo cleavage rate was significantly lower for good and low-quality oocytes exposed to heat stress (K2, K3, K4, K5, and K6), compared to good quality COCs of the control group (K1). The cleavage rate was lower for low quality (K2; 63 ± 1.28) than good quality COCs (K1; 53 ± 1.85). The percentages of oocytes that developed to the blastocyst stage were lower for K2, K3, K4, K5, and K6 than K1. Moreover, the blastocyst rate was lower for K2 (9 ± 0.22) than K1 (15 ± 0.22). The results of this study indicated that exposure of camel oocytes to heat stress for 6 hours during in vitro maturation severely reduced extrusion of polar body, cleavage, and blastocyst rates. The low-quality camel COCs were reduced developmental capacity than good quality oocytes. © 2020, World''s Veterinary Journal. All Rights Reserved
Mitochondrial Activity and Transcript Abundance of Quality Marker Genes during In vitro Maturation of Bovine and Buffalo’s Oocytes
(Nexus, 9/25/2021) Ghanem, Nasser; Samy, Romysa; Khalil, Beshoy SF; Abdalla, Ibrahim; Barakat, Hassan; Yousry, Ahmed; Ahmed, Sayed; Moheb, Esraa; Ismail, Ahmed; Diab, Ayman A.; Safwat, Gehan; Fakruzzaman, Md.; Kong, Il-Keun
In vitro embryo production is a well-known biotechnology tool to improve and sustain animal productivity. Therefore, optimization of this technique would enhance both animal productivity and farm profitability. The aim of the present study was to compare the mitochondrial activity and patterns of expression of genes that contribute to its regulation during the in vitro maturation of buffalo (Bubalus bubalis) and bovine (Bos indicus) oocytes. Ovaries were collected from local Egyptian abattoirs and cumulus-oocytes complexes (COCs)were aspirated from 2-8mm follicles diameter and were divided into four categories according to oocyte morphology. The grade A and grade B were cultured in TCM medium (supplemented with all required chemicals and hormones) for 22 hours at 38.5o C and collected after their in vitro maturation (IVM). The total RNA of the oocytes was then extracted and target mitochondrial transcripts (TFAM and CPT2) were analyzed by real-time PCR. The results of this work revealed the intensity of mitochondria and lipids was reduced in good than bad matured bovine oocytes. However, there was no change of mitochondrial and lipid fluorescent intensities of bad quality oocytes before and after in vitro maturation. The expression profile of CPT2 gene was higher in immature compared to matured oocytes of bovine while, buffalo oocytes did not shown differences in the expression of this gene. Furthermore, the expression profile of CPT2 gene was lower in immature and matured buffalo oocytes than those of bovine. The transcript abundance of TFAM did not indicate any differences among in vitro maturation of both species. It was concluded that the patterns of the gene expression of CPT2 vary during in vitro maturation of bovine oocytes in reflecting their maturation competence than that of buffalo. Increased metabolic activity of oocytes during IVM is in line with CPT2 expression that is involved in lipid oxidation required for this process.