<div>Background:&nbsp;The production of fishery resources and the abundance of new species in our markets are becoming increasingly important. The consumption of fish continues to increase. Microbiological analysis of fish provides information on the diversity of the bacterial population abundant in these species. 
 
Methods:&nbsp;Our work was based on the isolation and identification of the bacterial flora of two fish species bred in extensive mode at the Sidi M&rsquo;Hamed Ben Taiba dam (Barbel and Bighead carp). By introducing the influence environmental factors on the load and diversity of bacterial species by physicochemical (temperature, pH, turbidity, conductivity and dissolved oxygen) and bacteriological (search for total and faecal coliforms, enterococci and sulphate-reducing bacteria) analysis of the rearing water. 
 
Result:&nbsp;A variety of bacteria were isolated from the different compartments of the two fish species. Of which we were able to identify 12 species divided into 9 genera:&nbsp;Staphylococcus, Streptococcus, Pseudomomas, Serratia, Salmonella, Citrobacter, Proteus, Chrysobacterium, Stenotrophomonas and genera of lactic acid bacteria.</div>

Characterization of Microorganisms in Fish and Farmed Water from Sidi M&rsquo;Hamed Ben Tiba Dam (Algeria)

The fertilised eggs of Asian sun catfish, Horabagrus brachysoma (G&uuml;nther 1864) were demersal and pale yellow in colour with equal perivitelline space. First cleavage appeared at 49 min (&plusmn; 3 min) and the size of the blastomeres reduced as the development stage proceeded. Morula stage was reached 3 h 37 min (&plusmn; 15 min) post-fertilization. The embryonic development from morula to hatching took about 16-17 h. The hatching of eggs started at 20 h 46 min (&plusmn; 28 min) post-fertilization. The newly hatched yolk-sac larvae were 3-4 mm in length. A membranous layer was found covering from behind the head to posterior part of yolk-sac. Eye, mouth, alimentary canal, barbells and pectoral fins were appeared in the 3 days after hatch (dah). The membranous layer started rupturing at fifth day of post-hatch and disappeared during 9-12 dah with the appearance of fins in different parts of body. Pigments on dorsal side of body appeared in 2 dah larvae and the 10-12 dah larva looked pale brown in colour. After 12 dah, the larva morphologically resembled like an adult fish.

Characterization of Microorganisms in Fish and Farmed Water from Sidi M’Hamed Ben Tiba Dam (Algeria)

Embryonic and larval development of an endangered catfish, Horabagrus brachysoma