Pharmacological treatment of the reproductive cycle in cattle Flashcards
Modification of the reproductive cycle in female cattle
- Prostaglandin treatment
- Clinical application of GnRH
- Gestagen treatments
Prostaglandin treatments
Therapeutic use of prostaglandins
- 1935, Euler, prostate, seminal plasma
- 1982, Nobel prize: Bergström, Samuelsson, Vane
- C20, min. 1 C5
- Fields of application
- Shortening of luteal phase
- Oestrus synchronisation
- Enhancement of uterine contractions
- Cervix dilatation
Prostaglandin treatments
Prostaglandins used in the therapy
- Natural: dinoprost
* Synthetic : cloprostenol, luprostiol, fenprotalene
GnRH applications
Therapeutic approach of gonadotropin releasing hormones
• More, than3000 similar effect synthetized compounds
• Based on the affinity to the receptors:
o GnRH receptor agonists: leuprolid, buserelin, histrelin, goserelin, deslorelin, nafarelin, triptrolerin, gonadorelin
o GnRH receptor antagonists: abarelix, cetrorelix, degarelix, ganirelix
GnRH applications
Mechanism of GnRH hormone application
• GnRH agonists
o „Flare effect ”: Desensitisation of the pituitary. FSH↑, LH ↑
o „Receptor down regulation ”: More than 10 days of treatment
• GnRH antagonists
o FSH↓, LH ↓
GnRH applications
Modification of the decapeptide structure
- Increased dependence in the pituitary to GnRH and LHRH producing neurons
- Side effect decreasing (histamine like effects , allergy)
Gestagene treatments
5 days protocol
GnRH (5d) PGF2alpha (24h) PGF2alpha (48h) GnRH+TAI
7 days protocol
GnRH (7d) PGF2alpha (24h) PGF2alpha (32h) GnRH (16h) TAI
