Alterações histológicas e comportamentais provocadas pela inoculação de suspensão bacteriana (Aeromonas hydrophila) em juvenis de jundiá (Rhamdia quelen)

Abstract

Com objetivo de avaliar as alterações histológicas e comportamentais provocadas pela Aeromonas hydrophila em Rhamdia quelen, diferentes concentrações bacterianas (3,6 x 10 7 e 7,5 x 10 6 UFC -Unidade Formadora de Colônia/ml de solução salina) foram inoculadas por via intramuscular. Para este estudo, foram utilizados 80 juvenis de jundiá com peso e comprimento de 16,55g e 13,23cm, respectivamente. Esses peixes foram mantidos durante 10 dias, em caixas d'água de 250 litros, com condições iguais de temperatura, pH, alcalinidade e dureza. Os jundiás foram observados diariamente e, os moribundos, submetidos a cortes histológicos. Constatou-se então que a Aeromonas hydrophila causa perda de equilíbrio, apatia e exoftalmia, assim como alterações histológicas na pele do tipo necrose, hemorragia e infiltrado inflamatório, atingindo tanto a camada da epiderme como da derme e musculatura. Palavras-chave: ictiopatologia, A. hydrophila, jundiá SUMMARYThe purpose of this study was to evaluate the histological and behavior alterations induced by the inoculation of different concentrations of Aeromonas hydrophila in jundiás. Eighty (80) animals were used in this study, with 16.55g of weight and 13.23cm of length. Different bacterial concentrations (3.6 x 10 7 and 7.5 x 10 6 UFC -Unity Formation of Colony/ml of saline solution) were inoculated intramuscularly. The animals were kept for 10 days in amianthus aquarium (250 liters) with similar conditions of temperature, pH, alkalinity and hardness. The jundiás were observed daily and the dying ones were used for histological cuts. It was verified that the Aeromonas hydrophila caused balance loss, apathy, exophthalmia and histological alterations like necrosis, hemorrhage and inflammatory infiltrated, reaching the epidermis layer as well as the derme and musculature.

Morphological, microbiological and ultrastructural aspects of sepsis by Aeromonas hydrophila in Piaractus mesopotamicus

“…In fish, the infection by Aeromonas spp. causes rupture of small blood vessels, leading to cutaneous and fins hemorrhage, progressing to ulcerations with loss of epithelium, anemia, anorexia, lethargy, hemorrhagic sepsis and death [8,9].…”

Salinity on artificial reproduction of silver catfish (Rhamdia quelen)

“…One of the difficulties for massive catfish fingerlings development is the elevated concentration of the ciliated protozoan Ichthyophtirius multifilis, known as the white spot disease agent (BALDISSEROTTO & NETO, 2005), responsible for the mortality of high quantities of fingerlings and juvenile in a few days (BOIJINK & BRANDÃO, 2001). MIRON et al (2003) and ANDRADE et al (2006) proved the efficiency of NaCl (4g L -1 ) baths on the I. multifilis infestation of juveniles catfish.…”

Survival and behavior of silver catfish, Rhamdia quelen, submitted to antibiotics and sodium chloride treatments

“…One of these diseases is known as hemorrhagic septicemia, caused by Aeromonas hydrophila, an etiologic agent responsible for substantial economic losses in fish culture. It causes high mortality rate and also increase susceptibility to other diseases (BOIJINK & BRANDÃO, 2001).…”

“…Infestation with I. multifiliis was identified by the presence of white spots on the skin (MIRON et al, 2003) and infection with A. hydrophila was identified by superficial reddening of body surface (ROBERTS, 1993). Bacteriological evaluation was based on methods described by CARTER & COLE (1990). Skin lesions and gills specimens from three fishes were cultured in 5% ovine blood agar and Mac Conkey agar.…”