Doses - CHORIONIC GONADOTROPIN (HCG)

Dogs:

For cryptorchidism:
a) 500 Units injected twice weekly for 4-6 weeks (McDonald 1988)
For HCG Challenge test (to determine if testicular tissue remains in castrated male dogs; infemales to diagnose sexual differentiation disorders or if functional ovarian tissue remainsafter ovariohysterectomy):
a) Male dogs or females with suspected sexual differentiation disorder: Take sample forresting testosterone level. Administer 44 micrograms/kg HCG IM and take a 4 hourpost sample.
Female dogs: 100 - 1000 IU IM during apparent estrous episode. Measure progesterone level in 5-7 days. If above 1.0 ng/ml, this indicates functional ovarian tissue. (Shille and Olson 1989)
To produce luteinization of a persistent follicular cyst:
a) 500 IU IM; repeat in 48 hours. If effective, will convert from proestrus to estrus in 1-2days and sexual behavior should stop within 2 weeks. (Barton 1988)
For infertile bitches cycling normally with low progesterone due to lack of corpus luteumformation:
a) Next cycle, give 500 IU HCG SQ on days 10-11 of heat cycle or when vaginal smearindicates breeding readiness. Breed 2 days after HCG administration. (Barton and Wolf1988)
For male infertility secondary to low testosterone, LH and FSH:
a) HCG 500 IU SQ twice weekly for 4 weeks. Add PMSG (Pregnant Mare Serum
Gonadotropin) 20 IU/kg SQ 3 times weekly. If PMSG is unavailable, use FSH-P atsame dose (1 mg FSH = »10-14 IU). Continue for 3 months. Once spermatogenesisensues, may continue with HCG only. (Barton and Wolf 1988)

Cats:

For HCG Challenge test (to determine if testicular tissue remains in castrated male cats; infemales to diagnose sexual differentiation disorders or if functional ovarian tissue remainsafter ovariohysterectomy):
a) Male cats or females with suspected sexual differentiation disorder: Take sample forresting testosterone level. Administer 250 micrograms HCG IM and take a 4 hour postsample.
Queens: 50 - 100 IU IM during apparent estrous episode. Measure progesterone levelin 5-7 days. If above 1.0 ng/ml, this indicates functional ovarian tissue. (Shille and Olson 1989)
For infertility in queens due to confirmed ovulation failure:
a) 100 - 500 IU IM (Barton and Wolf 1988)
To induce ovulation in anestrus queens:
a) Give FSH-P 2 mg IM daily (for up to 5 days) until estrus is observed. Give 250 micrograms HCG on first and second day of estrus (Kraemer and Bowen 1986)
After artificial insemination:
a) 50 - 75 IU IM immediately after insemination; repeat insemination and injection in 24hours. (Sojka 1986)

Cattle:

For treatment of ovarian cysts:
a) 10, 000 Units deep IM or 2500 - 5000 Units IV, may repeat in 14 days if animal's behavior or physical exam indicates a need for retreatment. Alternatively, 500 - 2500 Units injected directly into the follicle. (Package Insert; Follutein®¯Solvay)

Horses:

For cryptorchidism:
a) Foal: 1000 Units injected twice weekly for 4-6 weeks (McDonald 1988) (Note: Manyclinicians believe that medical treatment is unwarranted and that surgery should beperformed.)
To induce ovulation in early estrus when one, large dominant follicle that is palpable with adiameter >35 mm is present:
a) HCG: 2000 - 3000 IU IV (preferable to treat mare 6 hours before mating) (Hopkins1987)
For treatment of persistent follicles during the early transition period:
a) 1000 - 5000 IU (results are variable). (Van Camp 1986)
To hasten ovulation and reduce variability of estrus after prostaglandin synchronization:
a) HCG: 1500 - 3300 IU 5-6 days after the second prostaglandin treatment or on the firstor second day of estrus. (Bristol 1986)
To induce ovulation after estrus has commenced:
a) 2500 - 4000 IU IM or SQ; ovulation generally occurs in 24-48 hours (Roberts 1986b)

Sheep & Goats:

For treatment of cystic follicles in does:
a) 250 - 1000 Units IV or IM (Smith 1986a)
Dosage Forms/Preparations/FDA Approval Status/Withholding Times - All HCG productsare prescription (Rx).
Chorionic Gonadotropin (HCG) Powder for Injection 5, 000 Units per vial with 10 ml of diluentto make 500 Units/ml
Chorionic Gonadotropin (HCG) Powder for Injection 10, 000 Units per vial with 10 ml ofdiluent to make 1000 Units/ml
Chorionic Gonadotropin (HCG) Powder for Injection 20, 000 Units per vial with 10 ml ofdiluent to make 2000 Units/ml
There are several products available with a variety of trade names, as well as many genericallylabeled products. Two commonly known products are A.P.L® (Wyeth-Ayerst) and Follutein® (Squibb). Veterinary-Approved Products are known to be available from
Solvay (Follutein®) and LyphoMed (generically labeled). There are chorionic gonadotropin products approved for use in dairy cat le and beef cattle. There are no withdrawal times for either milk or meat.