Open AccessProduction, Evaluation, Cultivation and In vitro Fertilization of Cattle Oocytes: Recent Trends in Reproductive Biotechnologies in Animal Breeding : A Review
Author(s) -
Vladimir A. Pleshkov
Publication year - 2021
Publication title -
bioscience biotechnology research communications
Language(s) - English
Resource type - Journals
eISSN - 2321-4007
pISSN - 0974-6455
DOI - 10.21786/bbrc/14.4.12
Subject(s) - oocyte , biology , andrology , human fertilization , in vitro fertilisation , hypodermic needle , anatomy , embryo , gynecology , medicine , genetics , psychiatry , syringe
The article presents the results of assessing reproductive biotechnology for cattle breeding. The issues of obtaining genetic material from bulls-producers and oocytes from donor cows, for their further cultivation and obtaining embryos, in order to replicate highly productive offspring from valuable animals, are considered. Oocyte production was analyzed in three different ways: puncture, section, and aspiration. A total number of 156 oocyte-cumulus complexes (OCCs) were collected out of 40 ovaries by puncture – 50 pcs, section - 47 pcs, and aspiration – 59 pcs. The results showed that puncture and section gave significantly higher total OCCs per an ovary (4.16 and 4.0, respectively) than aspiration (3.68), but a higher number of normal (grade A and B) OCCs per an ovary was observed with aspiration (2.5) than with puncture (1.82) and section (2.00). During aspiration, oocyte-cumulus complexes were collected from the surface of follicles with a diameter of 3 to 8 mm using a needle. During puncture, all surfaces were pierced with a hypodermic needle; during section, incisions were made along the entire ovarian surface with a scalpel, that is, all sizes of superficial follicles were collected. OCCs were divided into 4 classes based on cumulus and nucleus cells: grade A - oocytes completely surrounded by cumulus cells; Grade B - oocytes partially surrounded by cumulus cells; Grade C - oocytes not surrounded by cumulus cells; and grade D - degeneration observed in both oocyte and cumulus cells. Grades A and B were considered normal, while grades C and D were considered to be damaged. The obtained oocytes were cultured and fertilized in vitro, which means that their fertilization with sperm occurred under artificially maintained optimal conditions outside the body. Normal fertilization results are zygote formation with male and female pronuclei (PN). As a result of the conducted fertilization of 251 mature oocytes, 142 fertilizations were successful, which amounted to 56.57%.