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Chorulon® for fish

Chorulon® for fish

Chorulon® is a purified, sterile and highly effective preparation of chorionic gonadotrophin, which has been routinely used for nearly two decades to induce and synchronize the ovulation and spawning of various cultured fish species.

Chorulon® provides the fish farmer with a tool to eliminate losses due to partial ovulation and spawning, as well as to enhance egg quality, milt production, sperm volume and motility, and resulting fertilization rates. In comparison with the traditionally used crude fish pituitaries, Chorulon® has several further significant advantages which have become increasingly important in today's modern and intensive fish farming industry:

Chorulon® is the only hormonal spawning aid approved by the FDA in the USA for use in finfish (NADA no. 140-927). It is a freeze-dried preparation of human chorionic gonadotrophin (hCG) for administration after reconstitution in the accompanying sterile diluent. It has luteinizing hormone (GtH-II)-like activity with little or no follicle stimulating hormone (GtH-I) or oestrogenic activity.

After reconstitution, Chorulon® is administered via intramuscular injection just ventral to the dorsal fin for one to three injections. Any single injection should be administered, depending on the fish species, at a dose of 110 to 1120 I.U./kg body weight (bw) for males and 150 to 4000 I.U./kg bw for females.

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This general information is aimed at International Vets and Fish Farmers - to find specific regional information please select your country from the list below

© 2011 MSD Animal Health

Product indications, usage instructions & withdrawal periods may vary by Country.
Always follow label instructions and consult your veteriarian or fish health adviser.

This page contains information on veterinary pharmaceutical and biological products that are sold in several different countries and areas where they may be marketed under different trade names and pursuant to different regulatory approvals. Accordingly, TheFishSite and MSD Animal Health give no guarantee that the details presented are correct with respect to all locations.

Advertisments and/or reference to commercial products or trade names within information provided by does not constitute an endorsement by and does not imply discrimination against any other similar products. This information is aimed at veterinary surgeons, veterinary nurses, pharmacists or professional keepers of fish.

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