The nature and consequences of co‐infections in tilapia: A review

Abstract

Co‐infections commonly arise when two or multiple different pathogens infect the same host, either as simultaneous or as secondary concurrent infection. This potentiates their pathogenic effects and leads to serious negative consequences on the exposed host. Numerous studies on the occurrence of the bacterial, parasitic, fungal and viral co‐infections were conducted in various tilapia species. Co‐infections have been associated with serious negative impacts on susceptible fish because they increase the fish susceptibility to diseases and the likelihood of outbreaks in the affected fish. Co‐infections can alter the disease course and increase the severity of disease through synergistic and, more rarely, antagonistic interactions. In this review, reports on the synergistic co‐infections and their impacts on the affected tilapia species are highlighted. Additionally, their pathogenic mechanisms are briefly discussed. Tilapia producers should be aware of the possible occurrence of co‐infections and their effects on the affected tilapia species and in particular of the clinical signs and course of the disease. To date, there is still limited information regarding the pathogenicity mechanisms and pathogen interactions during these co‐infections. This is generally due to low awareness regarding co‐infections, and in many cases, a dominant pathogen is perceived to be of vital importance and hence becomes the target of treatment while the treatment of the co‐infectious agents is neglected. This review article aimed at raising awareness regarding co‐infections and helping researchers and fish health specialists pay greater attention to these natural cases, leading to increased research and more consistent diagnosis of co‐infectious outbreaks in order to improve control strategies to protect tilapia when infected with multiple pathogens.

Antiparasitic and Antibacterial Functionality of Essential Oils: An Alternative Approach for Sustainable Aquaculture

“…Using of these chemical substances cause mass killing of beneficial aquatic bacteria [13], produce multi-drugs resistant pathogens [14], and leaving residues in fish which can be transmitted to human [15,16]. These problems are the most concerning aquaculture sustainability [17,18], and infectious diseases and parasitic infestation treatment with natural substances/compounds are the demanding sustainable aquaculture features [19].…”

Copper Oxide Nanoparticles Alter Serum Biochemical Indices, Induce Histopathological Alterations, and Modulate Transcription of Cytokines, HSP70, and Oxidative Stress Genes in Oreochromis niloticus

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Lycopene reduces the impacts of aquatic environmental pollutants and physical stressors in fish

“…The drainage water contains non‐biodegradable pollutants, pesticides and herbicides that can be adsorbed by sediment particles and/or bioaccumulated inside the tissues of the aquatic organisms (Torre et al, 2013; El Megid et al, 2020). It may, in turn, negatively affect the human beings who consume the intoxicated fish resulting in dangerous health risks (Dural et al ., 2007; Abdel‐Latif et al, 2020a). These toxicants induce immunosuppression and oxidative stress on aquatic animals (Abdel‐Tawwab et al, 2017a; Abdel‐Tawwab et al, 2017b).…”