Introduction: the industry of aquarium fish is developing quickly in Iran and the number of people interested in keeping them
increases every day. In this regard, fish growers and reproducers are trying to respond to this increasing demand by increasing the
highly-demanded fish including sword tail aquarium live-breeding type. In fact, attempts have been made to improve the productivity
and regeneration of these fishes through researches, experimental operations, variations in temperature, and various diets.
Methodology: the current study was conducted on 80 sword fish aquarium live-breeding types in two aquariums over 90 days during
summer and autumn of 2013. Each of the 2 aquariums was divided to four sections. A certain degree of temperature was required for
each part of these aquariums and a heater was installed in every section to provide the required heat. The temperature of each section
was set respectively on 23, 25, 28 and 32 degrees centigrade. The results were later reported in the form of graphs and tables. The
behavioral observation of the fishes was also studied by monitoring the aquariums.
Results: we believe that rising temperature to 23 to 28 degrees centigrade increases the number of fully-fledged fetuses in sword fish
type. We also think that raising temperature to 28 to 32 degrees centigrade will decrease the number of non-fledged fetuses in sword
fish type.
Discussion and conclusion: according to the above mentioned results, we can say that a relative increase in temperature has positive
consequences on the evolution process of evolving fetuses, while an excessive increase in temperature has negative consequences on
the evolution process of evolving fetuses. Based on the collection of the results of behavioral observations in sword tail type, it is
possible that sword tail type members have group relations with their peers while swimming and feeding.