Chorulon is presented in vials as a white freeze-dried crystalline plug containing 1500 i.u. Chorionic Gonadotrophin PhEur together with solvent for reconstitution.
The active ingredient of Chorulon human Chorionic Gonadotrophin (hCG) is a complex glycoprotein with luteinising hormone (LH) activity. In the female hCG can be used to promote maturation of the follicle ovulation and the formation of the corpus luteum. In the male Chorulon stimulates the production of testosterone and thus influences the development and maintenance of primary and secondary male sexual characteristics.
Chorulon can be used in the following fertility problems in domestic animals:
| Species | Indication | Dosage and administration |
| Cow heifer | Repeated failure of conception | 1500 i.u.-i.m. or i.v. at Al or mating |
| Cystic ovarian disease (anoestrus
prolonged oestrus nymphomania) |
3000 i.u.-i.v. | |
| Mare | Suboestrus (follicles>2 cm in diameter |
1500–3000 i.u.-i.m. or i.v. repeat after 2 days if necessary |
| Induction of ovulation | 1500–3000 i.u.-i.m. or i.v. 24 hours before Al or mating | |
| Bitch | Anoestrus | 500 i.u.-i.m. or i.v. at first day of oestrus after pretreatment with PMSG 20 i.u./kg s.c. daily for 10 days |
| Delayed ovulation
prolonged pro- oestrus |
100–800 i.u./day i.m. repeating treatment until vaginal bleeding disappears. Mate on behavioural oestrus | |
| Male dog | Deficiency in libido | 100–500 i.u.-i.m. twice weekly for up to 6 weeks but if this is not possible then 100–500 i.u.-i.m. 6–12 hours before mating may give a temporary effect |
See table. Reconstitute with the solvent provided ensuring the freeze-dried plug is fully dissolved. Administer by intramuscular or intravenous injection observing the usual aseptic precautions.
In rare cases as with all protein preparations anaphylactoid incidents may occur shortly after injection. Adrenalin injection (1:1000) given intravenously or intramuscularly when symptoms appear is the standard treatment. The administration of corticosteroids may also be indicated.
Meat/Milk Nil.
For animal treatment only. Keep out of reach of children.
Store in a refrigerator at between +2°C and +8°C. Protect from light.
Any product not used immediately after reconstitution should be stored refrigerated between +2°C and +8°C. Reconstituted product remaining 24 hours after preparation should be discarded.
POM.
Packs containing 5 vials supplied together with solvent (each containing 5 ml).
Chorulon has been used in cases of cryptorchidism in the dog prior to castration (100–500 IU i.m. twice weekly for up to 6 weeks). Treatment may be effective in some cases provided that the inguinal canal is patent and that therapy commences early.
Chorulon has intrinsic LH-like activity. Injection of 1500 i.u. 12 days after heat in cattle enhances the active life of the corpus luteum by 2–3 days resulting in increased progesterone and suppression of oestradiol production. These changes are consistent with those observed after GnRH use at day 11–13 of the cycle which are believed to be responsible for the increased pregnancy rates seen after such use. The mode of action is however different since Chorulon does not rely on first stimulating an endogenous LH peak. This use of Chorulon has not been investigated in the field.
Vm 01708/4301.