ANTIBACTERIAL ACTIVITY OF ETHANOLIC GUAVA (PSIDIUM GUAJAVA) LEAVES EXTRACT AND ITS HEALTH STATUS EFFECT IN CULTURED OREOCHROMIS NILOTICUS

Samah.A.A and
Abeer A.M. Afifi

Fish health Dept., Central Laboratory for Aquaculture Research, Abbassa, Abu-Hammad.

Received 3/ 1/ 2016

Accepted 31/ 1/ 2016

Abstract

The effect of Guava leaves extract in vitro as antibacterial against some fish bacterial pathogen was detected. Guava leaves extract at concenteration 150 µg /disc had antibacterial effect against (Staphylococcus aureus, Streptococcus sp, Aeromonas sobria, A. jandaei and Pseudomonas fluorescence) isolates except Aeromonas veronii. One hundred and eighty apparently healthy O. niloticus (with average body weight 45 ± 2 g / fish) was collected randemly from Central Laboratory for Aquaculture Research, Abbassa, Abo-Hammad,Sharqia, Egypt for studing the effect of Guava leaves extract on healthstatus. The fish were divided into three groups in three replicates (each 20 fish). Fish of the first group served as a control and fed diet free from ethanolic guava leaves extract. Fish of second and third groups Guava leaves extract were fed with diet contained 0.5% and 1% ethanolic guava leaves extract respectively. The fish were fed to satiation two times a day for four weeks. Blood samples were collected at zero day, first, second and fourth week of feeding period. Challenge was occurred IP with pathogenic Aeromonas sobria at the end of feeding experiment, mortality rate and relative percent of survival were recorded. The result indicated that Heamatocrite, Lysozome and NBT where enhanced with fish groups fed diet supplemented with ethanolic guava leaves extract compaed with control group. Also it increased relative levels of protection.It had potentially protect fish against A.sobria infection.