Crestar
Crestar
Crestar is a part of a system suitable to control oestrus in heifers and cows in order to apply a planned insemination programme. Crestar consists of a Crestar implant containing 3 mg of the progestagen Norgestomet (17 alpha - acetoxy - 11 - Beta - methyl - 19 - norpregna - 4 - en - 2.20 - dione) and a Crestar injection of 2 ml, containing 3 mg Norgestomet and 5 mg Oestradiol valerate.
Indications
Oestrus control in both cyclic and non-cyclic cattle (heifers and cows).
Dosage
| Day 0 | 2 days before implant removal | Day 9 or 10 | Time of AI (one AI) | |
|---|---|---|---|---|
| Beef heifers | Insert Crestar implant | Remove Crestar implant | 48 hours after implant removal | |
| 2 ml Crestar injection i.m. | Inject 400-600 IU Folligon (PMSG) | |||
| Beef cows | Insert Crestar implant | Remove Crestar implant | 56 hours after implant removal | |
| 2 ml Crestar injection i.m. | inject 500-700IU Folligon (PMSG) | |||
| Dairy heifers | Insert Crestar implant | Remove Crestar implant | 48 hours after implant removal | |
| 2 ml Crestar injection i.m. | Folligon (PMSG) generally not required | |||
| Dairy cows | Insert Crestar implant | 2 ml PGF2a i.m. | Remove Crestar implant | 56 hours after implant removal |
| 2 ml Crestar injection i.m. | Inject 300-400 IUl i.m. Folligon (PMSG) |
Notes:
Cows and heifers can be inseminated without oestrus detection.
If two AI’s are performed the timing of AI is 48 and 72 hours after implant removal.
The dosage of Folligon (PMSG) depends on age, breed, season, post-partum interval, management, etc.
Withholding period
Milk:
nil
Meat:
2 days after removal of implant.
(National regulations should be observed).
Presentation
Box with 5x5 Crestar implants and 5x5 vials of 2 ml Crestar injection.
Storage
Store in a dry place at room temperature (15-25°C). Protect from light.
Contra-indications
- Crestar is not a therapeutic and therefore is to be applied in healthy animals only.
- Heifers to be treated should have reached at least 65-70% of the adult weight and the age should be 15-20 months, depending on breed.
- Cows should not be treated within 45 days after the last calving.
Further information
Crestar injection:
The oestrogen plus the Norgestomet compound shortens the luteal phase if treatment is given in an early stage of the cycle. At the same time the Norgestomet compound suppresses oestrus and ovulation by pituitary inhibition.
Crestar implant:
The continuous release of Norgestomet maintains the suppression of oestrus and ovulation. After removal of the implant the blocking effect on the pituitary ceases and a new follicular phase starts. In non-cyclic animals the priming effect of Norgestomet is enhanced by combining the removal of the implant with an intramuscular PMSG injection with the intention of stimulating follicular development.