الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
 |  | from | 53 |  |  |
| | | from | 53 | | |
المستخلص
This study was carried out for the determination of the most suitable and successful method for
induction of spawning in four carp species widely cultured in Egypt namely, Common carp,
Silver carp, Grass carp and Bighead carp. The possibie reduction of carp pituitary dose or other
hormone preparations through the use of dopamine inhibitors was also investigated. The
experiment was carried out in Fowa Governmental Artificial Hatchery, at Fowa city. it is
specialized in carp artificial propagation, using the German system. In the present work brood
carp fish were induced to spawn. The spawning stimulators used were:
• Pituitary gland extract, PGE (1St dose 3—6 mg/fish. 2’ dose 3—3.5 mg/kg hwt).
• PGE + Domperidone (151 dose 3—6 mg PGE + 1 mg Domperidone/fish. 2” dose 1.5 3.5 mg
PGE/kg bwt).
• PGE + Metoclopramide (1St dose 3—6 mg PGE + 5 mg Metocloprainide/fish. 2 dose 1.5—3.5mg
PGE/kg bwt).
• Human Chorionic Gonadotropin, HCG (151 dose 250—500 lU/kg bwt. 21d dose 1400 1800 lU/kg
bwt).
• HCG + Domperidone (1St dose 250—500 IU HCG/kg bwt + I mg Domperidone/fish. 2’ dose
700—750 IU HCG/kg bwt).
• HCG + Metoclopramide (1’ dose 250—300 TU HCG/kg bwt + 5 mg Metoclopramide/fish. 2 dose 700—750 lU/kg bwt).
St nd
• Buserelin (1 dose 0.004 mg/fish. 2 dose 0.004 mg/kg bwt).
• Lutofolone (1st dose 1 mI/female. 2 dose, 1 mi/kg bwt).
Female and male carp were treated with the above mentioned drug combinations. In Common carp, Grass carp and Bighead carp semi artificial propagation by putting males and females together in the same tanks until time of ovulation then fertilized eggs were collected. The parameters related to artificial propagation of the freshwater fishes included, quantity of spawn (kg) produced per female, total number of eggs/kg female body weight, percentages of eggs fertilized and hatched, time of stripping after the second injection (hours) for each female. It could be concluded that, fish spawning is the most important method that can improve the fish propagation and increasing the number of fish fries. The ideal spawning stimulators that can be used under Egyptian conditions are HCG and PGE and their eflects can be highly stimulated using some additives as domperidone and metoclopramide and their dosages can be decreased to the half percent with economic saving of the cost of spawning stirnulators.