Effect of Photoperiod (15 days light and 15 days dark) on Breeding Performance of Live Bearer Ornamental Fishes

Abstract

The present study was conducted to find out breeding performance of live bearer ornamental fishes such as
black molly (P. sphenops), guppy (P. reticulata) , Platy (X. maculatus) and Swordtail (X. helleri) using photoperiod (15
days (L) and 15 days (D)) phases alternately in a month and hence continued for a period of eight months. During first
four months, effect of photoperiod observed on brooder in which 15 days (L) and 15 days (D) phases were maintained in
four different glass aquaria setups named as SI
to SIV . Molly, guppy, platy and swordtail were kept in ratio of one male
and two females in four different glass aquaria setups, SI
to SIV respectively to observed their breeding performance such
as number of youngones, survival rate percent, mortality rate percent and colour changes. Same photoperiod phases
were maintained for next four months periods in four different glass aquaria setups named as SA to SD to observed effect
of photoperiod on growth performance of youngones such as average length, average weight, specific growth rate percent,
percent weight gain percent and colour changes. A proper water quality management were done throughout study period
and physico-chemical parameters such as temperature, dissolved oxygen, pH, nitrite, nitrate, ammonium, phosphate and
total hardness were observed and maintained using standard water analysis kits. Feed management were done using
dried pelleted and dried live frozen feed. Chemical analysis were done to disinfect brooder and their youngones
throughout study period using easily available chemicals from aquarium shops such as 'Rid - All – Copper Aid' , 'Rid- All
– General Aid' and methylene blue. The aim of present study was to found out whether this type of photoperiod 15 days
(L) and 15 days(D) phases were appropriate and successful for breeding or not; whether helpful in providing healthy
crops or not and whether going to boost our national income or not . From study it was quiet cleared that this photoperiod
phases should not be applied for breeding of the live bearer ornamental fishes. As mostly body colour faced changes
during dark phases, which created dullness and their beautiful appearance seemed to be lost which inturn brought total
economic loss.