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| ND 41 All-Male Tilapia hybrids, without hormonal treatment |
The key for Tilapia in colder subtropical and
temperate regions
The ND 41 is a hybrid Tilapia cross between:
· Female - O. aurea ND-4 Tilapia family line
· Male - O. aurea ND-1 Tilapia family line
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The economic traits of the ND-41 Tilapia hybrids are:
All-Male population without hormonal treatment for sex reversal
The ND 41 Tilapia hybrid are all males. The proportion of Tilapia males in any spawning cycle is
~ 98%, without hormonal treatment, and provided APT operational instructions are adhered to. Actually, the progeny is 100% genetic males. The lower percent reflects penetration of foreign fish, assuming stern protection methods are used.
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Docile behavior
ND 41 behaves less aggressively than
Tilapia O. nilotica. This becomes evident during sampling, sorting, selective harvesting and final harvesting. Fish are calm, not jumping and cooperate in routine farm activities. This results in reduced losses of fish throughout the production cycle.
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Fast growth
The growth rate of All Male population of ND-41 Tilapia hybrids is higher than
O. nilotica Tilapia in the temperature range of 22-25 °C, and lower than
O. nilotica in the temperature range of 29-31 °C.
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High fecundity
The ND 41 Tilapia hybrid yields 300 fry per-female per-month, at initial phase of maturity, reaching ~500 fry per female per month at full maturity. For production of 1000 ton per year, it is recommended to use a flock of 1000 ND-4 females and 250 ND-1 males.
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Spawning at low temperature
ND 4 and ND 1 will begin mating behavior at 18 °C. Mating and spawning is apparent in commercial flocks at 20 °C. Hence, the spawning cycle of the ND 41 cross is significantly longer than that of
O. nilotica in temperate zone and sub-tropical climate zone, and even during the 2 months of reduced temperature in Tropical regions.
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Sensitivity to Streptococcus infection
The ND 41 is as sensitive as O. nilotica. |
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