EFFECTS OF RECOMBINANT HUMAN GONADOTROPHINS DURING IN VITRO MATURATION OF DOMESTIC CAT OOCYTES
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The increase in the human population causes rapid depletion of natural resources and depletion or
extinction of wild species. Today, thirty-six species of wild cats face this danger. Biotechnological
methods such as Artificial Insemination (AI), In Vitro Fertilization (IVF), In Vitro Maturation (IVM),
Embryo Transfer (ET) and Cloning are used in the protection or management of these animal species. The
cat IVM studies have very variable results change from 2% to 78% in reaching metaphase II stage.
Maturation medium contents, gonadotropin types added to the media, duration of maturation, estrous
cycle phase and body condition of cats used as oocyte source are influential in the obtained results. LH
and FSH used in the maturation of oocytes are obtained from extraction of sheep or pig pituitary gland.
Obtaining of other substances or different hormones such as TSH with these hormones and different
concentrations during each synthesis effect superovulation and IVM studies. Recombinant human
gonadotropins are used in horses, cattle, sheep and cats in the reproduction studies, in order to avoid the
problems caused by the method of obtaining gonadotropins with pituitary origin and reduce the costs.
However, there has not been any study with the effects of different concentrations of recombinant human
LH (rLH) and FSH (rFSH) (0, 0.5, 1 IU/ml) in vitro maturation of cat oocytes. In this study, it was aimed
to investigate the effects of hormones at different concentrations on the Metaphase II rates of cat oocytes.
Domestic cat ovaries from mixed breeds and various stages of estrous cycle were collected after routine
ovariohysterectomy from Avcilar Municipality Stray Animals Sterilization and Rehabilitation Center.
Cumulus oocyte complexes were isolated from the follicles by repeatedly slicing the ovaries. Modified
SOF was used as IVM medium supplemented with antibiotics, 4 mg/ml BSA. Selected oocytes were
maturated at 38 °C for 48 h in four-well petri dishes. Depending on experiment, this IVM medium was
supplemented with different concentrations of rFSH, rLH, hypophysial LH(hLH) and FSH ( hFSH).
The production of proteins is necessary for cytoplasmic and nuclear development and viability of oocytes
in the in vitro maturation. However, the amount and source of rFSH and rLH hormones added to the
maturation media effect MII stage rates and the amount of protein accumulated in the oocytes. Especially
for the embryonic development of bovine oocytes, higher levels of rLH addition lead to higher rates of
MII and blastocysts. However, in our study, metaphase II rates in 1 IU/ml hLH and 1 IU/ml hFSH group
were lower than 0.5 IU/ml rLH and 0.5 IU/ml rFSH group (29%, 44%)(p <0.01).. This result indicates
that human recombinant FSH and LH due to dosage support the MII development in the in vitro
maturation of cat oocytes. In this study, 0.5 IU/ml rLH and rFSH concentrations that used for the first
time in cat IVM showed similar MII rates(44.62%, 38%) with the same concentrations of pituitary
originate hormone group (p>0.01). This results showed that use of 0.5 IU/ml human recombinant FSH
and LH in cat IVM studies is a good alternative in terms of achieving high rates of MII oocytes and costs.

Conference
Conference Title
4th International VETIstanbul Group Congress
Conference Country
Kazakhstan
Conference Date
May 11, 2017 - Jan. 1, 2021
Conference Sponsor
istanbul university