Morfofisiología

ABSTRACT Shrimp culture is one of the most lucrative and fast-growing sectors in marine aquaculture. However, culture intensification to meet the growing demands has increased the incidence of diseases, causing considerable economic losses. Outbreak prevention and control is mostly based on antimicrobial antibiotics, which is very controversial due to the accumulation of residues in the environment, increased resistance, and less consumer acceptance. As an alternatively , more environment-friendly methods are being suggested. The application of probiotics is a versatile procedure with broadly accepted benefits in shrimp production worldwide. Probiotics can control pathogens by means of multiple mechanisms, which can promote host growth and improve the quality of culture environment. Additionally, they can be administered through different routes in combination with other beneficial substances. This article offers an update on probiotic use in shrimp culture, with particular emphasis on production increase.
RESUMEN La camaronicultura es uno de los sectores más lucrativos y de mayor crecimiento dentro de la acuicultura marina; sin embargo, la intensificación del cultivo para satisfacer una demanda cada vez mayor ha incrementado la inciden-cia de enfermedades produciendo pérdidas económicas considerables. La prevención y control de los brotes se basa fundamentalmente en antimicrobianos, lo cual es criticado por la acumulación de residuos en el ambiente, el desarro-llo de resistencia y poca aceptación de los productos por parte de los consumidores. Alternativamente, se proponen métodos más amigables con el medio ambiente, como la aplicación de probióticos, un procedimiento de gran versati-lidad y considerables beneficios ampliamente aceptado en la producción de camarón a nivel mundial. Los probióti-cos son capaces de controlar patógenos por múltiples mecanismos, promover el crecimiento del hospedero y mejorar la calidad del ambiente de cultivo. Adicionalmente pueden ser administrados por varias vías y en combinación con otras sustancias beneficiosas. Este artículo provee una actualización sobre la aplicación de probióticos en el cultivo de camarón, con énfasis en su influencia en el incremento de la productividad.

Electroporation of Litopenaeus schmitti embryos was used to transfer the pE300tiGH15 plasmid that contains the tilapia growth hormone gene (tiGH) complexed with a nuclear localization signal peptide into the zygotes. The gene construct was detected in 35 (36%) of the 98 larvae screened by PCR and Southern blot analyses. Western blot analyses revealed that 34% of the screened larvae expressed a single tiGH-specific band with the expected molecular mass (23.1 kDa). The development index and larval length indicated a significant growth enhancement from day 3 on after electroporation, with an average of 32% of the growth enhancement. To our knowledge, this is the first report on gene transfer enhanced growth in crustaceans.

Tilapia growth hormone (GH) was used to determine the presence of a presumed protein with GH receptor-like function in the hepatopancreas of shrimp L. vannamei and to evaluate its effect on growth of L. vannamei postlarvae. The receptor assay was performed using brush border membrane vesicles (BBMV) from the hepatopancreas of L. vannamei and the affinity constant was calculated by the dilution coordinates method. The shrimp postlarvae treated with tilapia GH were 42.4% heavier and 5.2% longer than the control group (P b 0.05). On the other hand, the water content was lower in the postlarvae treated with GH (75.9%) than in the control group (77.3%) (P b 0.05). Content of soluble proteins per mg of weight was 1.33 times higher in the GH-treated animals than control animals. No significant differences in survival rates were detected between the experimental groups. Tilapia GH was able to bind to a GH receptor-like protein on BBMV with an affinity constant of 1.30 ⁎ 10 8 M − 1. In conclusion, a GH receptor-like protein was detected on vesicles from hepatopancreas of the shrimp L. vannamei. Also, it was established that the TiGH was able to enhance the growth of shrimp postlarvae. To our knowledge, this is the first report to demonstrate an interaction between a vertebrate growth hormone and a GH receptor-like protein of a crustacean.

Growth hormone (GH) has been shown to have a profound impact on fish physiology and metabolism. However, detailed studies in transgenic fish have not been conducted. We have characterized the food conversion efficiency, protein profile, and biochemical correlates of growth rate in transgenic tilapia expressing the tilapia GH cDNA under the control of human cytomegalovirus regulatory sequences. Transgenic tilapia exhibited about 3.6-fold less food consumption than nontransgenic controls (P < 0.001). The food conversion efficiency was significantly (P < 0.05) higher (290%) in transgenic tilapia (2.3 ؎ 0.4) than in the control group (0.8 ؎ 0.2). Efficiency of growth, synthesis retention, anabolic stimulation, and average protein synthesis were higher in transgenic than in nontransgenic tilapia. Distinctive metabolic differences were found in transgenic juvenile tilapia. We had found differences in hepatic glucose, and in agreement with previous results we observed differences in the level of enzymatic activities in target organs. We conclude that GH-transgenic juvenile tilapia show altered physiological and metabolic conditions and are biologically more efficient.

The genetic manipulation of shrimp is of interest for biological studies and biotechnological applications. In order to perform gene transfer experiments, chimeric genes must be designed and tested, and efficient gene transfer protocols must be established. ...

A genetic transformation system for penaeid shrimp could provide a powerful technique for the improvement of different production traits of importance for a sustainable aquaculture. The development of a successful transformation system depends on the ability to efficiently introduce exogenous DNA into the target species. The ability of the nuclear localization signal (NLS) peptide of the SV40 T antigen to facilitate nuclear import and transient gene expression is known from vertebrate systems and for the first time, is shown here to be efficient in a crustacean species, i.e. the shrimp Litopenaeus schmitti. Electroporation was used to introduce the pCMV-lacZ plasmid that contains the human cytomegalovirus promoter/enhancer (CMV) fused to the h-galactosidase (lacZ) coding region, into L. schmitti zygotes. Supercoiled DNA was used at 50 or 500 ng/Al naked or bound to NLS peptide. The hatching rate of electroporated zygotes was around 60% for all groups, except from the pCMV-lacZ:NLS group at 500 ng/Al (43%). Based on Southern blot analyses of polymerase chain reaction (PCR) products the gene transfer frequency was 2-fold higher using DNA:NLS complexes than with naked DNA (23.8% vs. 11.5%, with 50 ng/Al of plasmid DNA, 44.3% vs. 28.8% with 500 ng/Al). The h-galactosidase activity assay indicated that nuclear uptake is faster for the DNA:NLS complexes than for naked DNA. The h-galactosidase activity was always higher in the DNA:NLS groups than in the naked DNA groups. To our knowledge, this is the first report on the use of an NLS peptide to improve gene transfer and nuclear uptake in crustaceans.

Acuabio 1 is a mixture of proteins and essential amino acids that exerts a stimulating effect in the development of aquatic organisms. It synchronizes and accelerates fish and shrimp larvae growth on early developmental stages, as well as increases the development and size of these animals. In this work, the stimulating effect of Acuabio 1 on the immune system of Litopennaeus vannamei shrimps was demonstrated by obtaining (5.4 x 10 6 hemocytes/mL) greater than the control group (4.3 x 10 6 hemocytes /mL). The hemolymph of treated animals showed higher lectin titers (16) than the control group (8). Animals treated with Acuabio 1 increased their phenoloxidase and peroxidase activities, indicating an enhanced oxidative defense. Furthermore, Acuabio 1 decreased the number of Vibrio spp. and Pseudomonas spp. colony forming units in the culture medium, suggesting a possible prebiotic function. All these properties make Acuabio 1 very attractive to improve the production, survival rate and...

Acuabio 1, an enhancer of the immune system in Litopennaeus vannamei shrimps. Acuabio 1 is a mixture of proteins and essential amino acids that exerts a stimulating effect in the development of aquatic organisms. It synchronizes and accelerates fish and shrimp larvae growth on early developmental stages, as well as increases the development and size of these animals. In this

Acuabio 1 es una mezcla de proteínas y aminoácidos esenciales que ejerce un efecto estimulador en el desarrollo de los organismos acuáticos. Sincroniza y estimula el crecimiento de larvas de peces y camarones. Con su empleo se activa y acelera el mecanismo de crecimiento desde edades muy tempranas, así como el desarrollo y la talla de los animales. En el presente trabajo se evidencia el efecto estimulador del sistema inmune del producto Acuabio 1 en camarones (Litopenaeus vannamei). Se determinó que al tratar los animales con este producto aumentó el número de hemocitos totales (5.4 x 10 6 hemocitos/mL) con respecto a los del grupo control (4.3 x 10 6 hemocitos/mL). Se observó que la hemolinfa de los camarones tratados tuvo mayor título de lectinas (16) comparado con el control (8). En los animales tratados con Acuabio 1 se encontró un aumento de las actividades específicas fenoloxidasa y peroxidasa comparadas con las del control, lo que indicó un aumento de la defensa oxidativa en estos animales. También se halló que Acuabio 1 disminuyó el número de unidades formadoras de colonias en el medio para Vibrio spp. y Pseudomonas spp., lo que sugiere una posible función prebiótica. Estas propiedades del producto Acuabio 1 lo hacen muy atractivo para su utilización en el mejoramiento de la producción, supervivencia y calidad de las larvas de camarones.

Tilapia growth hormone (GH) was used to determine the presence of a presumed protein with GH receptor-like function in the hepatopancreas of shrimp L. vannamei and to evaluate its effect on growth of L. vannamei postlarvae. The receptor assay was performed using brush border membrane vesicles (BBMV) from the hepatopancreas of L. vannamei and the affinity constant was calculated by the dilution coordinates method. The shrimp postlarvae treated with tilapia GH were 42.4% heavier and 5.2% longer than the control group (P b 0.05). On the other hand, the water content was lower in the postlarvae treated with GH (75.9%) than in the control group (77.3%) (P b 0.05). Content of soluble proteins per mg of weight was 1.33 times higher in the GH-treated animals than control animals. No significant differences in survival rates were detected between the experimental groups. Tilapia GH was able to bind to a GH receptor-like protein on BBMV with an affinity constant of 1.30 ⁎ 10 8 M − 1. In conclusion, a GH receptor-like protein was detected on vesicles from hepatopancreas of the shrimp L. vannamei. Also, it was established that the TiGH was able to enhance the growth of shrimp postlarvae. To our knowledge, this is the first report to demonstrate an interaction between a vertebrate growth hormone and a GH receptor-like protein of a crustacean.

Cyathostomins are the most common and important group of large intestine nematodes, infecting horses worldwide. The current control strategy is associated with the development of anthelmintic resistance, which has been reported worldwide. Therefore, experiments with this family of parasites have become progressively important to provide their monitoring and control strategies. The aim of the present study was to propose a faster and more economic assay for isolation of genomic DNA from the adult stage of Cyathostomin parasites than reported. Adult parasites were collected from a single horse from a farm in São José dos Pinhais, PR, Brazil, and were identified. Genomic DNA was isolated from ten individual female adult parasites using a standardized procedure developed. Then, extraction from ten individual female was carried out by another DNA extraction method. DNA concentration from both methods were measured and compared. We obtained a good DNA quality with this standardized procedure. As a result of this analysis, we propose a modified phenol-chloroform method, which will contribute to assays that require DNA extraction from adult worms for genomic DNA sequences of cyathostomin, or species-specific identification. Tolliver, S.C., 2000. A practical method of identification of the North American cyathostomes (small strongyles) in equids in Kentucky.

Background: Worldwide, Fasciola hepatica infection causes high production losses in the livestock industry. Recently, studies have analyzed the association between measurements of F. hepatica infection intensity and herd management practices. The aim of the present study, the first of its kind in a subtropical region, was to evaluate associations between F. hepatica bulk-tank milk ELISA results with herd management factors and milk yield in dairy herds, in Camagüey, Cuba. The SVANOVIR® F. hepatica-AB ELISA was used to measure F. hepatica antibody levels in a random sample of 516 dairy herds during the period of May-July of 2014. Farm management practice data were collected using a questionnaire. Results: With 82% of the herds testing positive, the results indicate that F. hepatica is very widespread in this area. Reductions in milk production of 18 and 32% were observed in herds with Optical Density Ratios (ODR) of 0.3-0.6 and > 0.6, respectively, when compared to herds with ODR < 0.3. Overall, the longer the milking cows were put out to pasture, the higher the levels of anti-parasite antibodies. Co-grazing with sheep and goats also significantly increased the risk of high ODR. Conclusions: Our data show a widespread occurrence of the parasite as well as a major potential impact of the infection on the Cuban development goal of becoming self-sufficient in milk production. Our risk factor analysis suggests that the prevention of infection around water sources, and the separation of cattle from small ruminants could be useful control measures. This is the first epidemiological survey of F. hepatica abundance, and associated reductions in milk yield, in dairy herds in Cuba.

The aim of this study was to evaluate phage display technology for mapping Haemonchus contortus mimotopes. We screened the PhD-7 Phage Display Peptide Library Kit with a sheep polyclonal antibody against H. contortus. After four rounds of selection, 50 phage peptide clones were selected by biopanning and sequenced. Two clones displaying peptide mimotopes of H. contortus proteins were chosen for sheep immunization: clone 6 - mimotope of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and clone 17 - mimotope of a disorganized muscle family member (Dim 1). Twelve sheep were allocated into 3 groups of 4 animals as follow: G1: control group; G2/GAPDH: immunized with clone 6; and G3/Dim1: immunized with clone 17. Four immunizations were performed at intervals of seven days (0, 7, 14, and 21 days). On day 28 post initial vaccination, all groups were orally challenged with 2500 H. contortus infective larvae. The mimotope peptides selected by phage display were recognized by IgG from sheep ...

El objetivo del estudio fue evaluar la capacidad de protección en ovinos contra Haemonchus contortus de un péptido que mimifica epítopos de gliceraldehído 3-fosfato deshidrogenasa (GAPDH) y Desorganización Muscular (DIM-1) de H. contortus. Se hizo una búsqueda en una biblioteca de fagos (7 aa-GGG) con el empleo de un anticuerpo policlonal (IgG) anti-H. contortus. Después de tres rondas de selección se secuenciaron 120 clones y se hizo el análisis de secuencia de cada clon. Se seleccionaron clones cuya secuencia de péptidos fue similar a la proteína de DIM-1 y a la GAPDH, y se sintetizó un péptido con estos dos epítopos. Los animales se inmunizaron los días 0, 7, 14 y 28. Una semana después de la última vacunación todos los animales se desafiaron con 1250 L3 de H. contortus. La media de huevos por gramo de heces (hpg) y la carga parasitaria en el abomaso del grupo vacunado a los 70 días de la infestación se redujeron en 57.9 y 52.7%, respectivamente. Los niveles de IgG en suero fuero...

Gamma radiation produces DNA instability and impaired phenotype. Previously, we observed negative effects on phenotype, DNA methylation, and gene expression profiles, in offspring of zebrafish exposed to gamma radiation during gametogenesis. We hypothesize that previously observed effects are accompanied with changes in the expression profile of non-coding RNAs, inherited by next generations. Non-coding RNA expression profile was analysed in F1 offspring (5.5 h post-fertilization) by high-throughput sequencing 1 year after parental irradiation (8.7 mGy/h, 5.2 Gy total dose). Using our previous F1-γ genome-wide gene expression data (GSE98539), hundreds of mRNAs were predicted as targets of differentially expressed (DE) miRNAs, involved in pathways such as insulin receptor, NFkB and PTEN signalling, linking to apoptosis and cancer. snRNAs belonging to the five major spliceosomal snRNAs were down-regulated in the F1-γ group, Indicating transcriptional and post-transcriptional alteratio...

La camaronicultura es uno de los sectores más lucrativos y de mayor crecimiento dentro de la acuicultura marina; sin embargo, la intensificación del cultivo para satisfacer una demanda cada vez mayor ha incrementado la incidencia de enfermedades produciendo pérdidas económicas considerables. La prevención y control de los brotes se basa fundamentalmente en antimicrobianos, lo cual es criticado por la acumulación de residuos en el ambiente, el desarrollo de resistencia y poca aceptación de los productos por parte de los consumidores. Alternativamente, se proponen métodos más amigables con el medio ambiente, como la aplicación de probióticos, un procedimiento de gran versatilidad y considerables beneficios ampliamente aceptado en la producción de camarón a nivel mundial. Los probióticos son capaces de controlar patógenos por múltiples mecanismos, promover el crecimiento del hospedero y mejorar la calidad del ambiente de cultivo. Adicionalmente pueden ser administrados por varias vías y en combinación con otras sustancias beneficiosas. Este artículo provee una actualización sobre la aplicación de probióticos en el cultivo de camarón, con énfasis en su influencia en el incremento de la productividad.

Gene transfer has offered a new tool for the development of improved fish strains for aquaculture. However, characterization is required before these strains can be introduced into Ž. national aquaculture programs. Transgenic tilapia O. hornorum urolepis were produced by the Ž. microinjection into early embryos of a transgene containing the tilapia growth hormone tiGH Ž. cDNA under the regulatory sequences derived from the human cytomegolovirus CMV. A male containing 1 copyrcell of the transgene was selected to establish a transgenic tilapia line. The transgene was transmitted to F-F generations in a Mendelian fashion. Previous studies showed 1 4