Impact of ultrastructural and molecular identified Babesiosoma spp. in both Egyptian freshwater fishes (common carp and African catfish): Hematological, biochemical, and histopathological findings.

Background: Babesiosomes are apicomplexan parasites of both marine and freshwater fish species. Aim: In this study, we recorded the prevalence of Babesiosoma spp in two Egyptian freshwater fish species; the common carp and the African catfish with full pathological evaluation of the diseased condition, hematological and biochemical analysis of some parameters with exact recognition of the parasite with different methods. Methods: Two hundred and forty fish blood samples from Al-Sharqiya and Al-Ismailia governorates from August 2022 to January 2023 followed by blood film examinations, performing electron microscopy and molecular detection of the parasite via polymerase chain reaction. Results: The total infection prevalence was 63.75% with a higher prevalence observed among African catfish (42.5%) than Common carp (21.25%). Regarding hematologic parameters, the obtained results showed a significant decrease in the hematocrit values and a significant increase in the total leukocyte and lymphocyte values in both infected fish species. The serum ferritin, superoxide dismutase, and glutathione peroxidase were also significantly increased. However, the total iron binding capacity was significantly decreased. There was also a significant increase in the total serum bilirubin in the examined fish, all at (p < 0.001). Histopathologically, the lesions were more intense in the African catfish than the common carp but generally, the infected fish showed many changes with the gills being severely affected with pronounced hyperplasia of secondary lamellae with fusion and telangiectasis. The spleen, heart, and kidney are also affected. Conclusion: Serious adverse effects on the health status of previously examined fishes infected with Babesia spp. were observed and detected by several diagnostic and descriptive tools. Histopathological, hematological, and biochemical studies give an idea of the extent of these changes which are largely fatal affecting the economic system depending on the fish industry.

Pathognomonic features of Pasteurella multocida isolates among various avian species in Sharkia Governorate, Egypt.

The present study aimed to isolate Pasteurella multocida (P. multocida) from pulmonary cases in several avian species and then investigate the histopathological features, antimicrobial resistance determinants, virulence characteristics, and risk factors analysis of the isolates in each species in correlation with epidemiological mapping of pasteurellosis in Sharkia Governorate, Egypt. The obtained data revealed a total occurrence of 9.4% (30/317) of P. multocida among the examined birds (chickens, ducks, quails, and turkeys). The incidence rate was influenced by avian species, climate, breed, age, clinical signs, and sample type. Antimicrobial susceptibility testing revealed that all isolates were sensitive to florfenicol and enrofloxacin, while 86.6 and 73.3% of the isolates displayed resistance to amoxicillin-clavulanic acid and erythromycin, respectively. All of the P. multocida isolates showed a multiple-drug resistant pattern with an average index of 0.43. Molecular characterization revealed that the oma87, sodA, and ptfA virulence genes were detected in the all examined P. multocida isolates. The ermX (erythromycin), blaROB-1 (ß-lactam), and mcr-1(colistin) resistance genes were present in 60, 46.6, and 40% of the isolates, respectively. Ducks and quails were the most virulent and harbored species of antimicrobial-resistant genes. These results were in parallel with postmortem and histopathological examinations which detected more severe interstitial pneumonia lesions in the trachea and lung, congestion, and cellular infiltration especially in ducks. Epidemiological mapping revealed that the Fakous district was the most susceptible to pasteurellosis infection. Thus, farmers are recommended to monitor their flocks for signs of respiratory disease, seek veterinary care promptly if any birds are sick, and avoid the random usage of antibiotics. In conclusion, this study presents a comprehensive picture of the risk factors in correlation to the pathognomonic characteristics of P. multocida infection in poultry sectors to help in developing more effective strategies for prevention and control.