Effect of water temperature on the growth of nile tilapia fishes and on some affecting environmental factors [electronic resource].

Includes references.

This research studied the effect of temperature on the weight and length growth of Nile tilapia fishes, and on dissolved oxygen concentration, ammonia concentration and pH value of water. The experiments were carried out using five treatments throw 91 days. These five treatments conditions comprised testing the effect of levels of temperature at 20,25,28,30 and 35°C .The obtained data revealed that: - The most positive results in the weight and length growth of Nile tilapia fishes, were at the temperature of 28°C, especially for fishes having weight more than 50 g,while the treatments at temperature of 30°C had the most positive results for fishes having weight less than 50 g. - Increasing water temperature in aquarium caused in a continuous decrease in the dissolved oxygen and the change of its concentration was highly significant. - Increasing water temperature in aquarium resulted in a modest increase in pH values. - Increasing water temperature in aquarium caused in an increase in total ammonia concentrations. This study was ended by deriving some mathematical relations describing the effect of water temperature on both, weight and length growth of Nile tilapia fi5ihes, the dissolved oxygen concentration, ammonia concentration and pH value, Also, mathematical equation was derived for the relation between the weight and the length of Nile tilapia fishes.

Summary in Arabic.

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