Piaractus Brachypomus Research Articles

First report of microplastic ingestion by the alien fish Pirapitinga (Piaractus brachypomus) in the Ramsar site Vembanad Lake, south India

This study reports on the ingestion of microplastics by the alien fish Pirapitinga, Piaractus brachypomus (Characiformes; Serrasalmidae) that escaped Vembanad lake, the largest brackish water lake in the south-west coast of India, from the aquaculture systems during flooding. Microplastics separated from the gut of 32 out of the 123 fishes (26%) examined were identified using Attenuated Total Reflectance – Fourier Transform Infrared (ATR-FTIR), and Raman Spectroscopy. In total, 69 microplastic particles, represented by fibers, foam and fragments were recovered from the fish, with sizes ranging from 0.89 to 4.85 mm. The ATR-FTIR spectral analyses revealed the presence of polymers polyethylene and Nylon 6. The occurrence of PP, Nylon 6, PET and PBT were confirmed using Raman spectroscopy. The presence of MPs in the gut content of alien fish P. brachypomus could be a reflection of the increasing microplastics pollution in the estuaries and backwaters along the south-west coast of India.

NMR Approach for Monitoring Caranha Fish Meat Alterations due to the Freezing-Thawing Cycles

The fish meat shelf-life is highly influenced by temperature, making it necessary to use the cold chain to ensure freshness. Once this chain is stopped, unwanted reactions are initiated, and nutritional and texture changes in the meat may occur, compromising its consumption. Although these changes are important, it is not always possible for the consumer to differentiate between fresh and re-frozen fish due to the similarity when exposed to ice. In this context, the present study describes a metabolomic approach used to assess the influence on fish meat of the break in the cold chain by freezing-thawing cycles. Samples of caranha (Piaractus brachypomus) were used, and the metabolic profiles of frozen and frozen-thawed fishes were evaluated by nuclear magnetic resonance (NMR). The metabolic profile changes were identified through the chemometric treatment of NMR data and quantified using the Electronic Reference to Access In Vivo Concentrations (ERETIC 2) method. The results indicated the freezing-thawing cycles favored the increase of endogenous and exogenous enzymatic activities, expressed by variations in inosine, hypoxanthine, lactate, taurine, creatine, and trimethylamine amounts. This increase in metabolite concentrations, in particular inosine, hypoxanthine, and trimethylamine, was attributed as the main cause for the losses on fish meat quality and nutritional flavor, when compared with fresh fish.

Echinorhynchus gomesi Machado Filho, 1948 infecting the Patinga hybrid (♀ Piaractus mesopotamicus × ♂ Piaractus brachypomus ) in fish farms in Mato Grosso do Sul, Brazil

The fish farms state of Mato Grosso do Sul (Brazil) have been facing commercialization problems of the Patinga (Piaractus mesopotamicus (Holmberg, 1887) × Piaractus brachypomus (Cuvier, 1818)) due to hight acanthocephalans infection. The aim of this study was to identify the acanthocephalan species that infect this hybrid and assess the influence of management practices on the intensity of the parasite in fish farms. Samples were collected between October 2017 and June 2018. The transparency was the only water quality parameter that differed among the fish farms, and the values were below the limit established for fish production. Echinorhynchus gomesi was recorded in fish farms A, B and C. There was no significant correlation between the intensity of E. gomesi infections and the length of the intestine, and the standard length of the fish. The intensity of E. gomesi also did not affect the condition of the fish. The results of the study demonstrated that inappropriate management, such as cascading tanks, partial emptying of tanks and successive cultivations without time intervals, created conditions for the establishment of the population of E. gomesi in the evaluated fish farms.

Método alternativo de tinción ósea en peces juveniles empleando extracto de Bixa orellana

Actualmente el método de doble tinción empleado con rojo de alizarina y azul de alcian para tinción ósea y cartilaginosa, respectivamente, genera costos elevados en la realización de protocolos para estudios de anatomía y sistemática en vertebrados. El objetivo del presente trabajo fue comparar y analizar el colorante extraído de semillas de Bixa orellana con el rojo de alizarina en la tinción ósea en peces juveniles de Piaractus brachypomus. Se utilizaron 70 peces juveniles de 2 ± 0,4 cm de longitud total, los cuales fueron sedados utilizando 2 Fenoxi-etanol a concentración final de 500 mg/L y sacrificados en conformidad con las normas y procedimientos para el uso de animales de laboratorio. Posteriormente, se sometieron a una serie de fases para la conservación del tejido. Se distribuyeron 35 peces para cada tratamiento (rojo de alizarina y achiote) y se observaron e identificaron las estructuras óseas teñidas con cada uno de los colorantes. Además, se analizó la IE (intensidad de luz emergente) y DI (Densidad integral) en ejemplares diafanizados para cada tratamiento. No se observaron diferencias significativas para la IE (P = 0,10), a diferencia de la DI (p < 0,05) para columna vertebral y aleta dorsal. Concluimos que el colorante de Bixa orellana (achiote) presenta afinidad en estructuras óseas de peces juveniles y, por tanto, es una buena alternativa para la realización de la técnica de diafanización y estudios osteológicos de vertebrados a bajo costo.

Menthol as anaesthetic for red‐bellied pacu (Piaractus brachypomus) and its effect onHIF1aandGlucoRgene expression

Menthol as anaesthetic for red‐bellied pacu (<i>Piaractus brachypomus</i>) and its effect on<i>HIF1a</i>and<i>GlucoR</i>gene expression

Applying biofloc technology in the culture of juvenile of Piaractus brachypomus (Cuvier, 1818): Effects on zootechnical performance and water quality

The aim of this study was to assess the zootechnical performance and water quality of a cachama blanca (Piaractus brachypomus) culture using biofloc technology (BFT) versus a system with daily water exchange (DWE). To do this, 180 juveniles (mean initial weight: 5.40 ± 0.19 g) were distributed in 12 circular plastic tanks with stocking densities of 20 or 40 individuals m3; then, they were cultured for 91 days. BFT treatments kept a C:N ratio approximately of 15:1. Temperature, pH and oxygen were monitored daily, while the other variables were measured weekly. Most productive variables were significantly influenced by both culture system and stocking density with significantly higher values of daily weight gain, total weight gain and total length for fish kept in DWE 20. However, only minor differences were observed within the BFT system. With the exception of the toxic nitrogen compounds (NH4+ and NO2−), all the other water quality parameters were within the acceptable ranges for the cultivation of tropical fish. Microorganisms started to settle from the first week. A total of 23 genera were present, the most outstanding of which being seven genera of ciliates and three rotifers, rhizopods and chlorophytes. In conclusion, both systems BFT and DWE are useful for increasing the production of P. brachypomus in captivity. Additionally, the BFT system can potentially be applied for growing juveniles of this specie in regions with scarce water resources.

Morphology and molecular data of two novel cnidarian myxosporean (Myxobolidae) infecting Piaractus brachypomus from the Amazon basin

The objective of this study was reports, through morphological and small subunit ribosomal DNA (SSU rDNA) sequencing, two novel myxobolid myxosporeans infecting Piaractus brachypomus, an economicaly important Amazonian fish popularly known as “pirapitinga”. Of a total of 25 specimens of P. brachypomus examined 68% had the gill filament parasitized by Henneguya tapariensis n. sp. and 16% had infection of Myxobolus arapiuns n. sp. in the pyloric cecum. The morphological analysis revealed H. tapariensis n. sp. myxospores with an ellipsoid shape and caudal process larger than the length of the body. The polar capsules of same size were elongated and occupied less than half the body. Sequencing of the SSU rDNA generated a partial sequence of 1946 bp. In M. arapiuns n. sp. the myxospores had oval-shaped body and polar capsules of the same size, occupying less than half the body. Sequencing of the SSU rDNA generated a partial sequence of 1950 bp. Phylogenetic analysis revealed a cluster according to the order/family of the host, where H. tapariensis n. sp. was grouped in a subclade with Henneguya brachypomus and Henneguya piaractus and M. arapiuns grouped in a subclade with Myxobolus colossomatis, Myxobolus matosi and Myxobolus pirapitingae.

Infection outbreak for Piscinoodinium pillulare in Piaractus brachypomus from aquaculture farm in Brazilian cerrado

The Brazilian aquaculture stands out due to the climate and water availability, and grows along with the world fish production, due especially to the human population growth. The Piaractus spp. shows great participation in production due to the high economic value and productive performance, and because species of the genus are native from South America, including Brazil. Fish are susceptible to parasitizing infection by Piscinoodinium pillulare, a protozoa that causes a disease known as “rust disease”, even more at high population densities and stressful circunstances. An outbreak was observed in a semi intensive aquaculture farming property of Piaractus spp. for preservation, and without any commercial interest, in the municipality of Jataí, Goiás, Brazil, where the main characteristics were: dying fish on the water surface; petechiae in the ventral region of the body, especially in the abdomen; ulcers in the cranial portion; inappetence; and high mortality rates. Three specimens of P. brachypomus were captured and a scraped was performed on the body surface and gills and subjected to microscopic analysis. After microscopic analysis, P. pillulare was observed in slides of all samples. The diagnose was based only on the visualization of P. pillulare trophons (protozoa) in the skin and gills of the fish. The populational and climate conditions that P. brachypomus were exposed at Brazilian Cerrado are equivalent with those required to lead fish to stressful conditions and thus, make them susceptible to parasites infections, such as P. pillulare.

Study of protein extraction from residues of tambatinga amazon fish

The present work aimed to extract proteins from tambatinga fish residue with physicochemical characterization, a hybrid of the crossing between the female tambaqui (Colossoma macropomum) and the male pirapitinga (Piaractus brachypomus). Protein extraction was performed by the following methods: acid (hydrochloric acid, acetic acid) and basic (sodium hydroxide). The protein fraction was characterized in relation to moisture content, ash, protein and yield. The moisture determination was performed with powder samples, submitted to drying at 40 ° C, in a forced circulation oven, which presented values of 7.29; 11.42 and 3.14% respectively. Regarding the fixed mineral residue (ash), the samples differed from each other, with values between 81.52; 50.65 and 44.76%. The samples obtained by the different processes presented protein contents of 3.63; 9.36 and 39.55% respectively. And the yield of protein extraction was 8.96; 3.64 and 6.43% for hydrochloric acid, acetic acid and sodium hydroxide, respectively. The obtained results indicate that it is possible to perform protein extraction for fish waste utilization, mainly by the basic extraction method.

A proposal of standardization for histopathological lesions to characterize fish diseases

AbstractThe use of histopathology in fish sciences is broadly extended, although it is currently devoid of standardization across the literature. There have been initiatives to standardize every step of the histological evaluation, including description, diagnosis, interpretation, data recording and reporting, and statistical analysis, but, in general, the histopathological systems applied to date present a series of limitations that hamper the reproducibility of the derived data. On top of these limitations, an agreed, organ‐by‐organ list of lesions to be recorded is currently lacking. Therefore, this communication proposes a validated and comprehensive list of features to record in skin, head, eye, nervous system, gastrointestinal tract, gonads, kidney, and other organs of farmed red and Nile tilapias (Oreochromis sp. and Oreochromis niloticus L., respectively), white cachama (Piaractus brachypomus), rainbow trout (Oncorhynchus mykiss) and other species. Once this list is agreed and accepted by fish pathologists and other fish scientists, it could be the cornerstone for the development of well‐established and reproducible histopathological scoring systems. This communication highlights the importance of standardization initiatives in fish histology to produce reliable and high‐quality data.

Tambatinga juveniles performance in a recirculation aquaculture system with different stocking densities

In a quantitative field research, the objective of this work was to determine the best stocking density for tambatinga juveniles (Colossoma macropomum × Piaractus brachypomus) in a recirculation system during 50 days of cultivation. Tambatinga juveniles (0.72±0.02 g) were distributed in 0.08 m3 polyethylene boxes with densities of 5, 10 and 15 fish/box, with five replicates per treatment. During the experimental period, water quality, weight gain, apparent feed conversion, specific growth rate, carcass yield, proximate composition and final survival were evaluated. The water parameters remained stable and in the desired range for the species during the experimental period (temperature 25±1.52° C, pH 5.85±0.7 and dissolved oxygen 6.51±0.05 mg L-1). Statistical analyzes showed no significant difference for apparent feed conversion and survival rate. The lowest stocking density (5 fish/box) showed greater weight gain and specific growth rate, while the density of 10 fish/box showed high lipid deposition in the carcass. Aiming at greater weight gain and better specific growth rate, the results indicated that the density of 5 fish/box (0.08 m3), is the most suitable for juveniles of this species.

Novel myxosporean species parasitizing an economically important fish from the Amazon basin.

This paper provides morphological and phylogenetic analyses of two new myxobolid species found infecting Piaractus brachypomus from the Amazon basin. The fish were caught in the Tapajós River, in the municipality of Santarém, in the state of Pará, Brazil. The plasmodial development of Henneguya brachypomus n. sp. occurred in the gill lamellae while Myxobolus pirapitingae n. sp. developed in the pyloric cecum. Morphological analyses did not identify inflammatory infiltrate for either species, but H. brachypomus n. sp. induced stretching of the epithelium, compression of the adjacent tissues, and displacement and deformation of the neighboring lamellae. The mature myxospores of H. brachypomus n. sp. were ellipsoid, with a length of 11.7-13.8μm, a width of 4.0-4.6μm, and a thickness of 3.5-4.3μm. The polar capsules were elongated, with a length of 5.6-7.3μm and a width of 1.3-2.0μm, and each contained a polar filament with 8-9 coils. The caudal process was 40.5-48.1μm long and the total length of the myxospore was 52.4-61.6μm. Myxobolus pirapitingae n. sp. exhibited rounded mature myxospores measuring 10.0-11.1μm in length, 7.0-7.6μm in width, and 5.4-6.3μm in thickness. The polar capsules were of equal size and occupied less than half the myxospore, measuring 3.5-4.0μm in length and 2.0-2.6μm in width, with each containing a polar filament with 6-7 coils. Phylogenetic analysis based on partial small subunit ribosomal DNA (ssrDNA) sequences showed that H. brachypomus n. sp. clustered as a sister species of Henneguya piaractus, while M. pirapitingae n. sp. was grouped in a sub-clade together with Myxobolus matosi and Myxobolus colossomatis.

Effect of Catla catla roe protein isolate on textural and sensorial properties of surimi gel from Piaractus brachypomus

Influence of protein isolate from catla (Catla catla) roe at different levels (0–8%, w/w) on the textural and sensorial properties of surimi gel from red-bellied pacu (Piaractus brachypomus) were studied. Protein isolate from catla roe (CRPI) was prepared and evaluated for trypsin inhibitory activity. Surimi gels added with CRPI were subjected to shear stress, texture profile analysis, color, SDS-PAGE, microstructure, water holding capacity and sensorial analysis. CRPI had trypsin inhibitory activity of 771.7 ± 12.57 unit/g. The CRPI effectively prevented the degradation of myosin heavy chain (MHC) in a concentration-dependent manner in both modori (65/90 °C) and kamaboko (40/90 °C) gels. Nevertheless, surimi gels incorporated with 6% CRPI (w/w) exhibited higher textural properties. This was witnessed by higher shear stress, hardness, springiness, cohesiveness, gumminess, chewiness, adhesiveness, fracture force, and water-holding capacity for both gels (P < 0.05). Furthermore, increasing CRPI levels (8%, w/w) showed a detrimental effect on gelation. The whiteness of modori and kamaboko gels slightly decreased with increasing CRPI levels (P < 0.05). The microstructure of modori and kamaboko gels added with 6% CRPI was more ordered and compact with fewer voids, demonstrating a preventive effect of CRPI on hydrolysis of myofibrillar proteins. Moreover, both gels added with 6% CRPI presented the higher texture and overall likeness scores than that of gels devoid of CRPI (P < 0.05). Therefore, CRPI could be used as an alternative additive to improve the textural properties of red-bellied pacu surimi by mitigating autolysis caused by endogenous proteinase or serve as a co-gelling agent or binder.

Proximate composition, fatty acids and nutritional indices of promising freshwater fish species from Serrasalmidae family

ABSTRACT This study aimed to evaluate and compare the proximate composition and fatty acids (FA) profile of four fish species Piaractus mesopotamicus (PM), Colossoma macropomum (CM), Piaractus mesopotamicus X Colossoma macropomum (PC) and Piaractus brachypomus (PB). Fish fillets were analyzed for proximate composition, fatty acid profile, and nutritional quality indices. In general, PM and PB presented lower moisture content (73.75 ± 0.07 and 70.47 ± 0.16) and higher lipid content (4.34 ± 0.81 and 9.23 ± 1.16), respectively (p < 0.05). Although all species presented the same PUFA>MUFA>SFA pattern, PM and PB showed higher total n-3 FA values (mainly DHA and EPA), while CM had the lowest one (p < 0.05). Moreover, PM and PB exhibited superior nutritional quality indices, presenting the highest h/H ratio and the lowest IA and IT ratio (p < 0.05). A similar nutritional profile was observed for CM and PC. Therefore, PM and PB represent an excellent source of high-quality lipids, demonstrating that these freshwater fish species can be considered optimal for human consumption.

Parasitological assessment in hybrids Serrasalmidae fish farmed in Brazil.

This study evaluated the parasitic fauna of hybrids tambacu (Colossoma macropomum × Piaractus mesopotamicus) and patinga (P. mesopotamicus × Piaractus brachypomus) and their host-parasite-environment interaction during the warm and cold seasons in two fish farms located in the State of Mato Grosso do Sul, Brazil, South America. A total of 120 fish, being 60 fish for species (30 in the warm season and 30 in the cold season) were examined. Water quality was measured weekly to evaluate the interaction between environmental conditions and parasitism. Fifteen species of parasites were found: Ichthyophthirius multifiliis, Chilodonella hexasticha e Trichodina sp. (Protozoa), Henneguya piaractus, Myxobolus colossomatis and Myxobolus cuneus (Myxozoa); Anacanthorus penilabiatus, Mymarothecium boegeri, Mymarothecium viatorum, and Notozothecium janauachensis (Monogenoidea), Goezia spinulosa and Goezia sp. (Nematoda), Echinorhynchus jucundus (Acanthocephala), and Dolops carvalhoi, Lernaea cyprinacea (Crustacea). The ciliate protozoan I. multifiliis and monogenoids were the most prevalent parasites in the cold and warm seasons for both hybrids in the different culture systems intensive production and sportive fishing. It was observed that the serrasalmid hybrids are more susceptible to parasites and harbor high diversity of parasites in relation to the parental species C. macropomum, P. mesopotamicus and P. brachypomus, with a predominance of ectoparasites.

Organoleptic and nutritional characteristics of fillets of pirapitinga fed different protein sources in a biofloc system

Abstract: The objective of this work was to assess the organoleptic and nutritional quality of fillets of cultured pirapitinga (Piaractus brachypomus), fed diets with either partial or total substitution of fishmeal, and to determine the nutritional quality of the biofloc meal. Fish were cultured in 500-L tanks with 84 fish m-3, treated with biofloc technology (BFT), and fed three isoproteic diets (24% crude protein, CP) formulated with the following protein sources: soybean meal (SM); soybean meal + fishmeal (SM+FM); and soybean meal + spirulina (SM+SP). After 84 days of culture, microbiological, nutritional, and sensory analyses were carried out on fillets with skin and without scales. There were not significant differences for dry matter, CP, moisture, and fat content between treatments. The fatty acid profile showed 21.3±1.03% polyunsaturated fatty acids (PUFAs = ω-3 + ω-6), 37.11±1.29% monounsaturated fatty acids (MUFAs), and 41.58±1.34% saturated fatty acids (SFAs). The protein sources soybean meal and spirulina do not affect the fillet quality of pirapitinga nor the nutritional quality of biofloc meal.

Glycosaminoglycans from fresh water fish processing discard - Isolation, structural characterization, and osteogenic activity

Glycosaminoglycans (GAGs) play an important role in various biological activities. A lot of them are present in fish processing discards from abattoirs and fish processing industries which can serve as a valuable source of GAGs. We have, in this paper, isolated and characterized GAGs from fish processing discard (head) generated from the processing of Labeo rohita (L. rohita) and Piaractus brachypomus (P. brachypomus) and have determined their ability to promote osteogenic activity. Isolated GAGs showed higher amounts of chondroitin sulfate/dermatan sulfate (CS/DS) than heparan sulfate (HS). CS/DS from both the fish have a distinct disaccharide composition indicating differences in their structure. Biological activity, in terms of promoting osteogenesis, evaluated in MC3T3-E1 cells and primary cells of the calvaria showed that early mineralization, characterized by alkaline phosphatase staining and activity, and late mineralization, was supported by both the GAGs.

Pathological Effects and Lethal Concentration of Two Nonionic, Tallowamine-Polyethoxylate Surfactants in White Cachama Piaractus brachypomus

Two nonionic POEA surfactants (CAS No. 61791-26-2), TA15 and TH30, were tested to establish their acute pathological effects and lethal concentrations (LC50) in Piaractus brachypomus. Both compounds are nonionic surfactants produced by the alkoxylation of ethylene oxide with tallow amine, and they are used in variety of industries such as textiles, paints, metal working, agriculture, and polish manufacture. Fish were exposed to six concentrations of TA15 (0.2–4.0 mg/L) or TH30 (8–140 mg/L) for 96 h. The LC50 for TA15 was 2.08 mg/L and for TH30 47.32 mg/L. The main clinical signs observed in fish exposed to 4 mg/L of TA15 and 32 to 140 mg/L of TH30, were lethargy, loss of shoaling behavior, respiratory distress, changes in swimming pattern, such as, loss of balance and abnormal buoyancy, prolapse of the lower lip and superior location in the water column. The highest concentrations of these compounds induced nervous signs and collapse. The relevant macroscopic lesions were skin and fins erosions with necrotic lysis of the caudal peduncle. In addition, hemorrhages in mouth, branchial arches, and petechial hemorrhages in skin were observed. An increased fluid in the celomic cavity and meningeal hemorrhages were also evident. Organs as gills, liver, brain, and anterior kidney presented severe lesions at the highest concentrations of each compound. For the first time, it is reported lesions in interrenal tissues and choroidal bodies, as well as severe telencephalic lesions associated with the POEA toxicity. These last lesions were more severe in fish exposed to TA15 than to TH30, although the pattern of injuries was similar with both substances. According to the Global Harmonized System of Classification and Labelling of Chemical (GHS) by the United Nations, we reported that TA15 is classified as Acute Category 2 and TH30 is Acute Category 3 for white cachama. Due to the low LC50 and the highly toxic effects of both POEA compounds for neotropical fish, a revision of the regulation of the use of herbicide mixtures by Colombian legislation is necessary.

Parasites in farmed Piaractus brachypomus (Serrasalmidae) in the state of Acre, western Brazilian Amazonia

ABSTRACT This study investigated the parasite fauna in Piaractus brachypomus grown in fish farms in the state of Acre, in the western Brazilian Amazon. We examined 160 fish from four farms. Overall parasite prevalence was 66.9%. The fish were parasitized by Anacanthorus spathulatus, Mymarothecium viatorum, Anacanthorus penilabiatus, Clinostomum marginatum, Echinorhynchus jucundus and Henneguya sp., but monogenean species were the dominant parasites. Monogeneans showed an aggregated distribution pattern and there was a weak correlation between host size and abundance of M. viatorum and A. penilabiatus. No difference in the condition factor of parasitized and non-parasitized fish was detected. The fish of all farms had the gills parasitized by A. spathulatus and M. viatorum, but A. penilabiatus was found only in fish from two farms. Echinorhynchus jucundus, C. marginatum and Henneguya sp. were found in only one farm. The differences in parasitism level among the farms are attributable to differences in management and quality of cultivation environments.

EVALUACIÓN DE LA TOXICIDAD DEL CLORPIRIFÓS EN ALEVINOS DE CACHAMA BLANCA (Piaractus brachypomus)

Pesticides have become an important environmental problem due to their indiscriminate and lack of control use, which ends up affecting drastically non-target organisms, including aquatic species. The acute and chronic toxicity of chlorpyrifos was determined in fingerlings of red-bellied pacu ( Piaractus brachypomus ), and it was established the value of the median lethal concentration (LC 50 ) at 96 h, which was evaluated in 88 fish exposed to chlorpyrifos concentrations from 0.015 to 1.5 μg/L. The value established for CL 50 was 0.11 μg/L (p < 0.05). The chronic toxicity test to sublethal doses (0.5, 0.1 and 0.001 x of the LC 50 dose) was performed in 60 animals per treatment plus a witness group. Animals were exposed for 50 days, followed by 50 days without exposure, to evaluate both respiratory burst activity and plasma bactericidal activity in a challenge with Aeromonas hydrophila . Lower levels of respiratory burst were found in the exposed group to 0.0011 μg/L in 20 and 50 days, which increased in the exposed group to 0.055 μg/L at day 90. In addition, the bactericidal activity of plasma showed a decrease until day 40 in exposed animals compared to the witness. Also, in a trial of subchronic exposure without recovery to sublethal doses of chlorpyrifos (0.011 μg/L), lesions were found in gills, liver, kidney and brain. This study has demonstrated the high sensitivity of this species to chlorpyrifos, postulating P. brachypomus as a bioindicator of water pollution.