Impacto en las características morfológicas del músculo esquelético de los peces criados en granja / Impact in the morphological characteristics of the skeletal muscle of fish farm species

Introducción: El pescado es una fuente completa de proteínas de fácil digestión. Su aceite, vitaminas y minerales proporcionan un funcionamiento normal a todos los sistemas básicos del organismo. Estudiar las características del crecimiento postnatal del músculo esquelético del pez permite formular propuestas basadas en evidencias para la producción de carne de pescado de buena calidad. Material y Métodos: Estudio prospectivo de más de 300 especies de peces bajo principios análogos: edad joven de 20 a 500 días, de 860 días y con 2 a 3 años bajo crianza con tecnología de granja. El complejo metodológico incluyó morfometría, disección anatómica, métodos de preparación histológica, microscopio electrónico (Quanta 200 3D) y procesador estadístico. Resultados: Las condiciones tecnológicas y la conducta alimentaria garantizan el crecimiento del pez tipo pequeño (fingerlings). Según los registros del estudio, el incremento del peso del cuerpo de los peces carpa entre 15 y 135 días, fitoplankton para carpas plateadas sobre 190 y 301 veces, fitovorous para carpa herbívora, 128 a 302 veces. Discusión: El crecimiento vigoroso hiperplásico en el período inicial de la ontogénesis influye en el crecimiento posterior de los animales adultos. La dinámica estacional de las características morfométricas de las fibras musculares está influida por la intensidad de los procesos metabólicos del organismo.

Introduction: Fish as a food product is a source of complete, easily digested proteins, fish oil, vitamins, minerals which provide normal operation of all basic systems in the organism. Studying the general and specific characteristics of postnatal growth of fish skeletal muscles allow us to formulate evidence-based approach to the production of good quality fish. Methods: Prospective study of more than 300 species under analogue principles: : juveniles aged from 20 till 500 days, species aged 860 days at two- and three years farming technology. Complex methodological approach including morphometrics, anatomic dissection, histological set up methods with electronic scanning microscopy (Quanta 200 3D) was used. Statistical data processing was performed. Results: Technological conditions and feeding behaviour guarantee the intensity of fingerlings growth. According to our records carp increases body weight up to from 50 (at 3 year technology) to 411 times (at 2 year technology) between 15 and 135 days; phytoplankton silver carp up to 190-301 times, phytovorous grass carp up to 128-302 times respectively. Discussion: Vigorous hyperplastic growth of carps at early stages of postnatal ontogenesis influences on further growth of mature animals. Seasonal dynamics of morphometric characteristics of muscular fibers is determined by intensity of metabolic processes proceeding in organism.

Ectocommensal and ectoparasites in goldfish Carassius auratus (Linnaeus, 1758) in farmed in the State of São Paulo / Ectocomensais e ectoparasitas em kinguios Carassius auratus (Linnaeus, 1758) criados em fazenda no Estado de São Paulo

Concomitant infections by several parasitic genera are rare, very debilitating and often lethal to fish reared under commercial breeding conditions. Were describe a multiple and concurrent parasite infestation in cultured goldfish Carassius auratus with skin damage (nodules and/or ulceration). Fish with skin lesions underwent necropsy, and the skin and gills were scraped and examined. Histopathological examination with Hematoxylin-Eosin and Giemsa stain, and an ultrastructure study using transmission and scanning electron microscopy were conducted. In the skin, we identified multiple-parasite infestations by Gyrodactylidae, Epistylis sp., Trichodina sp., Ichthyophthirius multifiliis, Tetrahymena sp. and Ichthyobodo necator,associated with epithelial cell hyperplasia and epidermal sloughing. Although no gross lesions were observed, were identified a large number of parasites in the gills (Epistylis sp., Piscinoodinium sp., Ichthyophthirius multifiliis, Trichodina sp., Apiosoma sp., Hexamitasp. and cysts of a trematode digenean). The observed trematodes were not identified. The associated microscopic lesions were epithelial hypertrophic and hyperplasic and exhibited fusion of secondary lamellae and epithelial cell detachment. This is the first description of a protozoan Vorticella sp. parasitizing goldfish in Brazil. Multiple ectoparasitism by protozoa and Platyhelminthes, with or without apparent tissue damage, can be fatal for goldfish raised on farms with poor management.

A infestação concomitante por vários gêneros de parasitas é uma condição rara, debilitante e letal para os peixes e está geralmente associada aos problemas ambientais e de manejo. Com o objetivo de descrever os ectoparasitos presentes em kinguios Carassius auratus com lesões cutâneas, cultivados em fazenda comercial, foram analisados 30 exemplares de peixes por esfregaços de pele lesionada e de brânquias; exame histopatológico de tecidos corados pela técnica de Hematoxilina-Eosina e Giemsa e estudo ultraestrutural por microscopia eletrônica de transmissão e varredura de tecidos coletados após necropsia. Nas lesões cutâneas, foram observados os parasitos: Gyrodactylidae, Epistylis sp., Trichodina sp., Ichthyophthirius multifiliis, Tetrahymena sp. e Ichthyobodo necator, associados à hiperplasia epitelial, descamação epidérmica e presença de infiltrado inflamatório. A infestação das brânquias, mesmo sem lesão macroscópica, evidenciou Epistylissp., Piscinoodinium sp., I. multifiliis, Trichodina sp., Apiosoma sp., Hexamita sp. e cistos de trematódeo associados à hipertrofia e hiperplasia epitelial, fusão de lamelas secundárias, descamação epitelial e presença de infiltrado inflamatório. Os trematódeos observados não foram identificados. É a primeira descrição do protozoário Vorticella sp. parasitando kinguios no Brasil. O ectoparasitismo múltiplo por protozoários e platelmintos, com ou sem lesão aparente, pode ser fatal em peixes cultivados em condições ambientais precárias.

Benzocaína e eugenol como anestésicos para o quinguio (Carassius auratus) / Benzocaine and eugenol as anesthetics for golden fish (Carassius auratus)

Avaliaram-se os tempos de indução e recuperação de quinguios (Carassius auratus) expostos a dois anestésicos, eugenol e benzocaína. Foram utilizados 128 juvenis com peso médio de 2,07±0,53g e comprimento total médio de 5,51±0,56cm. A benzocaína mostrou ser mais eficiente do que o eugenol em relação ao tempo, tanto para indução ao coma quanto para a recuperação à fuga e também no que diz respeito à sobrevivência. As doses de benzocaína com melhores resultados foram de 87,5 e 100mg.L-1. O eugenol proporcionou demora na indução e na recuperação dos animais, além de ter apresentado mortalidades quando as doses anestésicas foram elevadas.

The aim of this work was to evaluate the induction and recuperation time of quinguio (Carassius auratus) exposed to two anesthetics, eugenol and benzocaine. 128 juveniles with 2.07±0.53g of average weight and 5.51±0.56cm of total length were used. The benzocaine proved to be more efficient than the eugenol regarding the time in inducing a coma and recovering flight, as well as survival. The better results of benzocaine doses were 87.5 and 100mg.L-1. The eugenol resulted in a delay of animal induction and recovery, and also presented mortalities when the anesthetics doses were increased.

Modulation of rhodopsin gene expression and signaling mechanisms evoked by endothelins in goldfish and murine pigment cell lines

Endothelins (ETs) and sarafotoxins (SRTXs) belong to a family of vasoconstrictor peptides, which regulate pigment migration and/or production in vertebrate pigment cells. The teleost Carassius auratus erythrophoroma cell line, GEM-81, and Mus musculus B16 melanocytes express rhodopsin, as well as the ET receptors, ETB and ETA, respectively. Both cell lines are photoresponsive, and respond to light with a decreased proliferation rate. For B16, the doubling time of cells kept in 14-h light (14L):10-h darkness (10D) was higher compared to 10L:14D, or to DD. The doubling time of cells kept in 10L:14D was also higher compared to DD. Using real-time PCR, we demonstrated that SRTX S6c (12-h treatment, 100 pM and 1 nM; 24-h treatment, 1 nM) and ET-1 (12-h treatment, 10 and 100 pM; 24- and 48-h treatments, 100 pM) increased rhodopsin mRNA levels in GEM-81 and B16 cells, respectively. This modulation involves protein kinase C (PKC) and the mitogen-activated protein kinase cascade in GEM-81 cells, and phospholipase C, Ca2+, calmodulin, a Ca2+/calmodulin-dependent kinase, and PKC in B16 cells. Cells were kept under constant darkness throughout the gene expression experiments. These results show that rhodopsin mRNA levels can be modulated by SRTXs/ETs in vertebrate pigment cells. It is possible that SRTX S6c binding to the ETB receptors in GEM-81 cells, and ET-1 binding to ETA receptors in B16 melanocytes, although activating diverse intracellular signaling mechanisms, mobilize transcription factors such as c-Fos, c-Jun, c-Myc, and neural retina leucine zipper protein. These activated transcription factors may be involved in the positive regulation of rhodopsin mRNA levels in these cell lines.

Distúrbios morfológicos em leucócitos de exemplar de kinguio (Carassius auratus auratus Linnaeus, 1758) com septicemia hemorrágica bacteriana: relato de caso / Morphologic disorders in leukocytes of goldfish sample (Carassius auratus auratus Linnaeus, 1758) with bacterial hemorrhagic septicemia: case report

O presente estudo teve por objetivo relatar um caso sobre as alterações morfológicas em leucócitos de kinguio comsepticemia hemorrágica bacteriana. Um exemplar foi atendido no Laboratório de Patologia de Organismos Aquáticos doCAUNESP, Unesp de Jaboticabal, apresentando apatia, natação errática, anorexia e discreta perda de equilíbrio, buscandoconstantemente a superfície da água. Através de análise visual da superfície corpórea, foram observadas áreas de hemorragiapetequial na base das nadadeiras peitoral, pélvica e caudal, além da órbita bucal, periocular e anal e efusão celomática. Naextensão sanguínea foram observadas a presença de monócitos ativados, hiperativados, e fagócitos mononuclearesrealizando eritrofagocitose e leucofagocitose, neutrófilos com basofilia citoplasmática e com vacuolização citoplasmática,além de imunócitos e leucócitos imaturos com anisocitose e anisocariose. As alterações morfológicas descritas no presenteestudo revelaram parte da patogenia e resposta orgânica de kinguio com septicemia hemorrágica bacteriana. Dessa forma,as análises qualitativas das células sanguíneas devem ser também utilizadas como ferramenta complementar aos estudosdo estado geral da saúde de peixes em cultivo.

The morphological changes in leukocytes of goldfish with bacterial hemorrhagic septicemia were reported. One sample was served at the Laboratory of Pathology of Aquatic Organisms of CAUNESP, Unesp in Jaboticabal. The fish showed lethargy, erratic swimming and without force, slight loss of balance, trying constantly to the water surface. In the body inspection, areas of petechial hemorrhage at the base of the pectoral fins, pelvic fins and caudal fin were observed, beyond the periocular and oral orbitand anal. Blood smears presented hiperactivated monocytes, performing erythrophagocytosis and leukophagocytosis, the cytoplasm of neutrophils presented basophilia and vacuolization, beyond immunocytes, immature leukocytes with anisocytosis and anisokaryosis. The morphological changes described in this study revealed part of the pathogenesis and organic response of Kinguio with bacterial hemorrhagic septicemia. Then, the qualitative analysis of blood cells should also be used as a complementary tool to study the general health status of fish farmed

Crescimento e sobrevivência de larvas de peixe vermelho (Carassius auratus) alimentadas com microdietas comerciais / Growth and survival of Carassius auratus larvae fed commercial micro diets

Para avaliar o desempenho de dois alimentos comerciais para larvas de peixes ornamentais e analisar o efeito que a suplementação em vitaminas e minerais teria sobre a sobrevivência e o crescimento dessas, foi realizado um ensaio de crescimento de 21 dias, com 4800 larvas de peixe vermelho (Carassius auratus), distribuídas por 24 grupos (200 indivíduos por grupo). Cada grupo foi alojado em tanques de 5L de capacidade, ligados a um sistema de recirculação de água. Quatro grupos foram alocados a um controle de jejum, em que os animais não foram alimentados, e os restantes 20 grupos foram utilizados em cinco tratamentos, em quadruplicado. Em cada um dos cinco tratamentos, os peixes ingeriram uma das seguintes dietas: R (referência), C1 (SERA vipan® baby), C2 (SERA® microgran), C1v e C2v (C1 e C2, respectivamente, reforçadas em vitaminas e minerais). As taxas de sobrevivência e crescimento dos peixes do tratamento R foram maiores que as obtidas nos outros tratamentos (P<0,05). Foram ainda observadas diferenças significativas entre tratamentos relativamente ao comprimento e peso totais. Face aos resultados observados, conclui-se que as duas dietas comerciais, com e sem suplementação, não parecem ser adequadas para o preenchimento das necessidades nutricionais de larvas de peixe vermelho.

A 21-day growth trial was performed to evaluate two ornamental fish larvae commercial diets and the effect of mineral and vitamin supplementation of the same commercial microdiets on growth and survival of goldfish larvae (Carassius auratus). A total of 4,800 larvae were randomly distributed in 24 groups of 200 individuals. Each group was housed in a 5L tank, connected to a recirculating water system. Four groups were assigned to a fastening control. The animals in these groups did not receive any food. The remaining 20 groups were distributed in five treatments, in quadruplicate. The animals of each treatment were fed one of five experimental diets: R (reference), C1 (SERA vipan® baby), C2 (SERA® microgran), C1v, and C2v (C1 and C2, respectively, reinforced with minerals and vitamins). At the end of the trial, high survival and growth rates were observed in R treatment. There were significant differences in total length and total weight among dietary treatments. Considering the high survival and growth rates of goldfish larvae obtained with the reference diet, it can be concluded that the two commercial diets tested, with or without mineral and vitamin supplements, do not seem suitable for feeding goldfish larvae.

L-histidine reduces inhibitory avoidance in Carassius auratus submitted to cerebellar ablation

The effect of post-training treatment with L-histidine (LH) on the memory consolidation of inhibitory avoidance was investigated in Carassius auratus submitted to cerebellar ablation. The inhibitory avoidance procedure included 3 days: one habituation day, one training day (5 trials, T1-T5) and one test day. On the training day, each fish was placed individually in a white compartment separated from a black compartment by a sliding door. When the fish crossed into the black compartment, a weight was dropped in front of it (aversive stimulus) and the time to cross was recorded. Saline or LH (100 mg/kg) was injected intraperitoneally 10 min after the trials. Data were log10 transformed and analyzed by ANOVA and the Student-Newman-Keuls test (P < 0.05). In T5, all groups [ablation/LH (N = 15; 189.60 ± 32.52), ablation/saline (N = 14; 204.29 ± 28.95), sham/LH (N = 14; 232.36 ± 28.15), and sham/saline (N = 15; 249.07 ± 25.82)] had similar latencies that were significantly higher than T1 latencies [ablation/LH (89.33 ± 20.41), ablation/saline (97.00 ± 25.16), sham/LH (73.86 ± 18.42), and sham/saline (56.71 ± 17.59)], suggesting acquisition of inhibitory avoidance. For the test, there was a significant reduction in latencies of ablation/LH (61.53 ± 17.70) and sham/saline (52.79 ± 25.37) groups compared to the ablation/saline (213.64 ± 29.57) and sham/LH (199.43 ± 24.48) groups, showing that cerebellum ablation facilitated retention of inhibitory avoidance and LH reversed the effect of ablation. The results support other evidence that LH impairs memory consolidation and/or reduces the interpretation of aversion value.

Chlorpheniramine facilitates inhibitory avoidance in teleosts submitted to telencephalic ablation

The present study investigated the involvement of H(1) histaminegic receptor on the acquisition of inhibitory avoidance in Carassius auratus submitted to telencephalic ablation. The fish were submitted to telencephalic ablation 5 days before the experiment. The inhibitory avoidance procedure included 1 day for habituation, 3 days for training composed of 3 trials each (1st day: T1, T2, T3; 2nd day: 2T1, 2T2, 2T3; 3rd day: 3T1, 3T2, 3T3) and 1 day for test. On training days, the fish were placed in a white compartment, after 30 s the door was opened. When the fish crossed to a black compartment, a weight was dropped (aversive stimuli). Immediately after the third trial, on training days, the fish received, intraperitoneally, one of the pharmacological treatments (saline (N = 20), 8 (N = 12) or 16 (N = 13) µg/g chlorpheniramine, CPA). On the test day, the time to cross to the black compartment was determined. The latency of the saline group increased significantly only on the 3rd trial of the 2nd training day (mean ± SEM, T1 (50.40 ± 11.69), 2T3 (226.05 ± 25.01); ANOVA: P = 0.0249, Dunn test: P < 0.05). The group that received 8 µg/g CPA showed increased latencies from the 2nd training day until the test day (T1 (53.08 ± 17.17), 2T2 (197.75 ± 35.02), test (220.08 ± 30.98); ANOVA: P = 0.0022, Dunn test: P < 0.05)). These results indicate that CPA had a facilitating effect on memory. We suggest that the fish submitted to telencephalic ablation were able to learn due to the local circuits of the mesencephalon and/or diencephalon and that CPA interferes in these circuits, probably due an anxiolytic-like effect.

Initial sexual maturity and fecundity of the goldfish Carassius auratus (Perciformes: Cyprynidae) under semi-controlled conditions

We studied the time of initial sexual maturity and the fecundity of the goldfish Carassius auratus under semi-controlled conditions. During the study the water temperature fluctuated from 21 to 30 degrees C, the pH between 7 and 8, and the dissolved oxygen between 5.5 and 7 ppm. Sixty days old juvenile fish received prophylactic treatments of brackish water (15 per thousand) and methylene blue baths (1%), and they were fed with live Daphnia magna. The initial sexual maturity occurred between 225 and 233 days of captivity. Mean absolute fecundity was 2,347 (+/- 302.2 SD) ova per gonad, and mean relative fecundity was 63.44 eggs/g fish weight. Gonadosomatic index was between 7.5 and 9.0. Our data will allow ornamental fish producers to calculate the time of initial maturity and fecundity for this species.

Estudiamos el tiempo inicial de madurez sexual y la fecundidad del pez dorado Carassius auratus en condiciones semi-controladas. Durante el estudio la temperatura del agua varió de 21 a 30 oC, el pH entre 7 y 8, y el oxígeno disuelto entre 5.5 y 7 ppm. Jóvenes de 60 días de edad recibieron tratamiento profiláctico con agua salobre (15 ‰), y baños de azul de metileno (1 %). Se les alimentó con Daphnia magna. La madurez sexual inicial fue tras 225 a 233 días en cautiverio. La fecundidad absoluta media fue de 2 347 (±302.2 DS) óvulos por gónada y la fecundidad relativa fue de 63.44 óvulos/g del peso del pez. El índice gonadosomático se calculó entre 7.5 and 9.0.

Capacidad larvívora del gold fish (Carassius auratus auratus) y del guppy salvaje (Poecilia reticulata) sobre larvas de Aedes aegypti en condiciones de laboratorio / Larvivorous capacity of the gold fish (Carassius auratus auratus) and the wild guppy (Poecilia reticulata) on larvaes of Aedes aegypti in laboratory conditions

El control biológico de vectores de importancia médica se presenta como una alternativa al uso de plaguisidas. La utilización de peces larvívoros se promueve como una nueva estratégia para el control de vectores. El propósito de este estudio es evaluar el potencial de dos especies ícticas para el control biológico de mosquitos Aedes aegypti (principal vector de dengue) en condiciones de laboratorio. Un creciente número de larvas de A. aegyptis en estadíos I, II y III (n: 25, 50, y 100) fueron colocados en acuarios con goldfish (Carassius auratus) y guppys salvajes (Poecilia reticulata). Se cuantificó la relación peso corporal/larvas ingeridas/hora en diez ensayos. La especie Poecilia reticulata reflejó una mayor (P<0,001) capacidad larvívora que C. auratus, dado que cuando se administraron 25, 50 y 100 larvas, los Poecilia reticulata obtuvieron valores promedio de eliminación de 3,15 ± 0,12; 5,50 ± 0,31 y 10,95 ± 0,25, respectivamente, frente a 1,21 ± 0,03; 2,45 ± 0,02 y 4,73 ± 0,06 de los C. auratus. Los resultados obtenidos son indicativos de que bajo las condiciones ensayadas, ambas especies de peces poseen alta capacidad de eliminación de larvas de mosquito A. aegypti; sin embargo, consederando su capacidad larvívora, disponibilidad, costo, características reproductivas y resistencia a las condiciones climáticas, la especie Poecilia reticulata ofrece ventajas importantes ante C. auratus auratus cuando ambos se evalúan integralmente como controladores poblacionales de mosquitos vectores.

Reinforcing properties of the substance P C-fragment analog DiMe-C7 in Carassius auratus

The aim of the present study was to investigate whether two substance P (SP) fragments have reinforcing effects in Carassius auratus when the fish were tested in a place-preference experimental model. Fish were placed in a 3-compartment box in which one compartment gives access to two others that are not connected. The time spent in each compartment was recorded for 10 min in order to determine which one was preferred. Twenty-four hours later the fish were given one of the following ip treatments: 1) group VEH (N = 12), injected with teleost saline, 2) group DiMe-C7 (N = 12), injected with 33 mug/kg DiMe-C7, and 3) group SP1-7 (N = 12), injected with 167 mug/kg SP1-7. Immediately after treatment the fish were kept for 30 min in the compartment that was the least preferred on the day before and this procedure was repeated for 3 days. On the fifth day the fish were retested for 10 min to determine the time spent in each compartment. Two-way analysis of variance with treatments and testing as factors indicated a main effect (P<0.0025) as well as a testing effect (P<0.009). The post-hoc Scheffé multiple comparison test indicated that only the DiMe-C7 group presented an increase in the time spent in the paired compartment after treatment. We suggest that the C-tenninal fragment of SP has reinforcing effects in Carassius auratus.