Progesterones
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The main function of progesterone is to establish and maintain preganacy, by preparing the uterine endometrium for implantation and by preventing myometrial uterine contractions during pregnancy.
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It also acts as a negative feed back hormone during the ovarian cycle suppressing LH and FSH secretion, oestrus and ovulation.
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In some species, it primes behavioural centres in the brain and so allows estradiol to induce behavioural estrus.
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It is produced mainly from the corpus luetum and the placenta and to a lesser extent from the adrenal gland.
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In the pregnant animal, the corpus leuteum is maintained for the duration of pregnancy, except in the mare.
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In some species such as the sow and the goat, the luteal progesterone is required throughout pregnancy: in other species such as the mare and the ewe, the placental progesterone is the primary source after day 100 in the mare and day 55 in the ewe.
Uses
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Control of ovulation
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Induction of ovulation
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Reduce embryonic loss.
Synthetic progesterones
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Medroxy progesterone (MAP) – used to control estrus and ovulation in the cyclic ewes and to induce estrus in anoestrous ewes. It can be used in bitches to suppress the onset of next estrus./font>
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Flurogesterone acetate (FGA) – used to control or induce estrous in ewes.
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Melengesterol acetate (MGA) – used to suppress estrus in heifers
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Norgestomet – used to control or induce ovulation
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Proligestone – used to control estrous in bitches.
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Last modified: Thursday, 26 April 2012, 5:14 AM