Pathologische Veränderungen bei roten Schwertträgern (Xiphophorus helleri) aufgrund einer Infektion mit motilen Aeromonaden

Abstract

A herd of red swordtail fish (Xiphophorus helleri) was reared in outdoor concrete ponds and suffered from occasional mortality. Moribund fishes showing abdominal dropsy and fin rots were sent for diagnosis. Gross necropsy findings showed enlargement of liver, spleen, and kidney in concurrence with congestion, and a severe accumulation of peritoneal fluid. Histopathological findings revealed an alteration of hepatocytes, with a severe diffuse accumulation of fat vacuoles in the cytoplasm. In the trunk kidney, severe accumulation of mononuclear cells together with cloudy swelling of the renal tubular epithelium was observed. From internal organs of the fish motile Aeromonas spp. were identified. The pathological findings might be associated with a long-term infection of affected fish fostered by common stressors such as improper feeding and poor pond environment condition (water temperature). Effective therapeutic measures comprised an advancement of keeping conditions and appropriate feeding to improve the health status in combination with the application of antibiotic substances.

Limited performance of MALDI‐TOF for identification of fish Aeromonas isolates at species level

“…Several species-specific polymerase chain reaction (PCR) assays have been developed for most of the Aeromonas with clinical relevance (Beaz-Hidalgo, Latif-Eugenin & Figueras, 2013) but the diversity of species of this genus associated with disease in fish and the difficulty for an etiological presumptive diagnosis based on the clinical symptoms (Bunnajirakul, Pavasutthipaisit & Steinhagen, 2015) might impair their routine use.…”

Low Concentrations of Antibiotics Alter Microbial Communities and Induce High Abundances of Antibiotic-Resistant Genes in Ornamental Water

“…However, previous studies reported that antibiotic drugs were administered to fish at concentrations ranging from 30 to 200 mg/kg to during aquaculture [23]. Imitating similar aquaculture patterns, the use of high concentrations of antibiotics ensured that the growth of animals in ponds was good but caused a great deal of antibiotic contamination [24]. Additionally, it remains unknown whether the structure of the microbial community and the abundance of ARGs and intI1 are affected by the external inputs of low concentrations of antibiotics in water.…”