تأثير العمر و فترة الموسم (التجميع الحراري)‎ على وقت و نسبة الاستجابة لأمات أسماك الكارب الشائع Cyprinus Carpio L. 1758 في مفاقس الاسماك

الملخص EN

This study was conducted to investigate the effect of spawners age and heat summation of common carp females.

Heat summation were measured on 1/1/2016.

The experiment started in the first stage in 16 / 3 / 2016 and it finished in the last stage in 13 / 5 / 2016.

The fishes were divided into three age groups for each group of artificial multiplication.

The results of study showed that the heat summation and spawners age revealed the significant effect (P<0.05) on fish.

The temperature affected on the ratio and duration of spawners response to hormonal injection and the required time for the fish responding to injection decreased gradually with elevation of temperatures.

The lowest heat summation in first group the experiment was about (784 degree / day), the fish took the responding time (13.03, 12.

3 and 12.01) hour for smallest aging spawners < 3 years, (3-4 years) and (than> 4 years) respectively and the significant superiority for largest and medium groups.

In the last experiment in heat summation (1886 degree / day) and responding time (8.03, 8.04 and 8.30) hour for spawners respectively response, the ratio of responding were in first experiment (100% , 85.7% , 75% ) a large then medium then smallest age, when last experiment which(92% , 75% , 83% ) smallest then medium then largest.

We conclude that with the high values of heat summation, old spawners were the best at the beginning of the season.

Small-aged spawners were the best at the end of the season, and middle-aged spawners hadn't changed significantly.