RESUMO: Buscamos por um impacto positivo de utilidade nas espécies invasoras como Pterygoplichthys spp. Foi avaliado o nível ótimo de substituição da farinha de sardinha (SM) pela farinha de Pterygoplichthys spp. (PML) em dietas práticas para tilápia do Nilo (Oreochromis niloticus). Foram utilizadas seis dietas experimentais; 50% PLM-50% SM, 60% PLM-40% SM, 70% PLM-30% SM, 80% PLM-20% SM, 90% PLM-10% SM e 100% PLM-0% SM. Em sistema de recirculação foram colocados 270 filhotes de tilápia machos (0.7 ± 0.1 g). As dietas foram triplicadas, o experimento durou 56 dias com amostragem a cada 14 dias, não houve diferença estatística para o crescimento. No final do experimento, foram determinados SGR, ADG, CF, WG, DFI, FCR e PER, não encontrando diferenças significativas (P> 0,05), embora tenha havido uma tendência indicando maior WG e PER na dieta 90% PLM-10% SM (93,56 ± 0,43% e 8,44 ± 1,18 g). A sobrevida foi superior a 90%, sem diferenças significativas. Além disso, não houve diferenças significativas na composição proximal de todo o peixe, enquanto o aparente coeficiente de digestibilidade de proteínas (81-90%) e lipídios (87-93%) também não mostrou diferenças significativas. Podemos concluir que o uso de 100% de farinha de Pterygoplichthys spp. pode substituir 100% de farinha de sardinha na alimentação de jovens O. niloticus sem afetar a sobrevivência, o crescimento, a composição química e a digestibilidade aparente dos nutrientes.

ABSTRACT: We search for positive utility impact on the invasive species Pterygoplichthys spp. The optimal level of replacement of sardine meal (SM) by Pterygoplichthys spp. meal (PLM) in practical feeds for fry of Nile tilapia (Oreochromis niloticus) was evaluated. We evaluated six experimental diets: 50% PLM-50% SM, 60% PLM-40% SM, 70% PLM-30% SM, 80% PLM-20% SM, 90% PLM-10% SM and 100% PLM-0% SM. In a recirculation system, 270 sex-reversed tilapia fry were used (0.7 ± 0.1 g). Diets were administered in triplicate and the experiment lasted 56 days with sampling every 14 days. There were no statistical differences in growth. At the end of the experiment, the SGR, ADG, CF, WG, DFI, FCR and PER were determined without significant differences (P > 0.05) between treatments, but there was a tendency that could indicated higher WG and PER in the 90% PLM-10% SM treatment (93.56 ± 0.43% and 8.44 ± 1.18 g, respectively). All survival rates were higher than 90% with no significant differences. Additionally, there were no statistical differences in the chemical composition of the whole fish, while apparent digestibility coefficients of protein (81-90%) and lipids (87-93%) also showed no significant differences. We concluded that 100% PLM can replace 100% SM in feeding fry of O. niloticus without affecting their survival, growth or chemical composition or the apparent digestibility of nutrients.

RESUMO: Nós medimos o efeito de baixa, normal e alta salinidade (5, 35 e 50ppt) na digestibilidade aparente da matéria seca, proteína e energia em duas dietas formuladas e seis comerciais para camarão juvenil do Pacífico, Litopenaeus vannamei. Os coeficientes de digestibilidade aparente da matéria seca, proteína e energia foram determinados in vivo utilizando o óxido crômico como marcador inerte nas dietas (peso inicial médio de 4g), em um teste de 120 dias. Hidrostabilidade na dieta de 86,8% a 99,9%, os coeficientes de digestibilidade da matéria seca variaram de 49,1 a 64,1%, os coeficientes de digestibilidade da proteína apresentaram maiores variações em todas as salinidades (56,9-85,8%), enquanto os coeficientes de digestibilidade da energia variaram de 70,1 a 86,4%. Efeito significativo da salinidade na digestibilidade da matéria seca, proteína e energia foi encontrado. Esses resultados, usando a análise de componentes principais (PCA) com a matriz de covariância, sugerem que a dieta E2 (fórmula à base de farinha de peixe) e salinidade a 35 ppt é ideal para a hidrostabilidade e digestibilidade das dietas para juvenis de camarão-branco-do-Pacífico.

ABSTRACT: This study evaluated the effect of low, medium, and high-water salinity (5, 35, and 50 ppt) on the apparent dry matter, protein, and energy digestibility of two formulated and six commercial diets for juvenile whiteleg shrimp, Litopenaeus vannamei, in a 120-day trial. Digestibility was determined in vivo using chromic oxide as an inert diet marker. Hydrostability in pellets varied from 86.8% to 99.9%; dry matter digestibility varied from 49.1% to 64.1%; protein digestibility showed greater variations at all salinities (56.9%-85.8%); and energy digestibility ranged from 70.1 to 86.4%. Salinity had a significant effect on dry matter, protein, and energy digestibility. Using a principal component analysis (PCA) with a covariance matrix, our findings suggested that the E2 (fishmeal-based formulation) diet and 35 ppt salinity provided optimum hydrostability and digestibility to Pacific white leg shrimp juveniles.

ABSTRACT. This research study is focused on the lipid requirements of Petenia splendida (0.65 ± 0.19 g) juveniles. Fish were fed with trout commercial diet (Silver Cup™ - 45% protein and 16% lipids), as control diet - CD (which is usually used to feed this species at commercial scale), and four isoproteic (45% crude protein) diet formulated with different lipid levels (5, 10, 15 and 20%). Diets were administered for 60 days by triplicate per treatment. Our results showed that fish fed with 10, 15 and 20% lipid levels were significantly higher (P < 0.05) in average weight and total length. Same treatments were significantly lower (P < 0.05) in terms of FCR compared to those shown in 5% and CD. However, fish fed 20% lipid level, showed a significant decrease in WG and a significant (P < 0.05) increase in FCR compared to those shown in 15% lipid level. Fish fed with 15% showed the highest weight gain and the lowest FCR compared with the rest of the treatments. Lipid efficiency ratio (LER) showed significant (P < 0.05) differences among experimental groups. Compared to other diets containing lipid levels (5, 10, and 20%) fish fed 15% diet recorded the lowest protein and lipid content in whole body. Additionally, based on second order polynomial regression analysis of WG, it was demonstrated that 16.2% lipid provides an optimal growth for P. splendida.

ABSTRACT: Lipids requirement of tropical gar Atractosteus tropicus prejuveniles and juveniles was evaluated on growth, survival, chemical composition and apparent digestibility coefficient (ADC). Four semi-purified experimental diets (5, 10, 15 and 20% of lipids) were obtained with a mix of menhaden oil and soybean lecithin (2:1 ratio). Two trials were carried out, first with 600 prejuveniles of 0.5 g (35 days post-hatching, dph) for 56 days, and the second with 160 juveniles of 15 g (two-months-old) for 42 days. In the first trial, 15 (40.8 g) and 20% (40.2 g) lipid diets showed the best weight. Significant differences were obtained in condition factor (CF), daily lipid intake (DLI), hepatosomatic index (HSI), crude protein, ashes, nitrogen-free extract, moisture and ether extract between treatments. In the second trial, fish fed with the 10% lipid diet obtained the highest weight (89.1 g) compared with the other treatments. Significant differences were recorded for weight gain (WG), feed conversion ratio (FCR), specific growth rate (SGR), condition factor (CF), and lipid efficiency rate (LER). Also, significant differences were obtained in crude protein, ether extract, NFE, gross energy, apparent lipid ADC, protein ADC and dry matter ADC. The polynomial models applied to both trials indicated an optimum lipid requirement of 17% for 0.5 g juveniles and of 9% for 15.2 g juveniles.

ABSTRACT Previous studies have shown that crustacean feed attractability has an enormous importance, because the consumption, quality and feed conversion rate can be improved, by reducing the time of residence pre-ingestion and the leaching of nutrients. For this reason, different protocols and methods has been developed to measure feed attractability. This study evaluated the use of maze type Y, and rectangular systems to determine the attractant power of a commercial feed on longarm river prawn Macrobrachium tenellum. The Y type maze system without barriers, and with three different types of barriers (with or without access to the area where a commercial feed) was evaluated. Ten prawns were placed in the acclimation chamber of the system at 28°C for 60 min before the start of the experiment. To start the test, commercial feed (20% of prawn biomass) was placed into the system feeding area, then the acclimation chamber was open to allow for the free prawn movement, evaluating the feed attractability by measuring the time for the first “hit”, total number of hits, and the number of prawns which entrances to the feeding area during 15 min. Similar tests were performed with a rectangular type maze system, comparing the atractability results obtained in both systems. The results presented here highlight the importance of the genus behavior and the selection of protocols and systems, as well as the materials used in its maze system construction, for attractability testing in M. tenellum.

ABSTRACT Due to the cost of raw materials, the need to formulate balanced feeds with highly digestible ingredients is indispensable for the aquaculture feed industry. For this reason, the protein in vitro digestibility, assessed by the pH-stat method, of ingredients with potential of using them on the balanced feed for Macrobrachium tenellum, were evaluated. The relative protein digestibility was assessed in twelve feed ingredients, including animal (pork meal, feather poultry meal, prime poultry meal, turkey meal, fish meal, shrimp meal), vegetal (coconut paste, chickpea meal, soybean meal, wheat gluten) and microbial (yeast and Spirulina meal); casein (Hammerstein grade) was used as the reference protein. The highest relative protein digestibility was found in: Spirulina meal (52.6%); following by pork meal (45.6%), and feather poultry meal (39.6%). The lowest digestibilities were found in soybean meal (15.9%), chickpea meal (12.1%), and fish meal (11.6%). The protein digestibility value should be considered for selecting potential ingredients for the formulation of balanced feeds for M. tenellum.

ABSTRACT The present work evaluates the attractant and palatable potential of six ingredients of animal origin in longarm river prawn Macrobrachium tenellum juveniles in a Y type maze system. Ingredients were pelletized for the first bioassay and included in neutral gelatin (in wet base) in the second bioassay. The ingredient to evaluate was placed in one of the Y-maze arms, allowing the free movement of prawn for 15 min. On both bioassays, attractability was evaluated by quantifying the time required for the first prawn to enter the region where the feed was found and the total of prawns which entered that region. In the second bioassay, also evaluated the palatability quantifying the time for the first prawn to have contact with the ingredient, the total of prawns which had contact with it and the time they remained feeding. No significant differences were obtained between treatments in the first bioassay. Significant differences were found in the second bioassay showing that pork meal, fish meal, feather meal and shrimp meal have greater attractability due to the number of prawns attracted, results also show significant differences in palatability, where fishmeal, shrimp meal and pork meal stimulating a higher number of organisms and promoting a longer consumption time.

Food production for aquaculture requires finding other protein sources or ingredients as potential alternatives in the formulation of aquaculture feeds, due to the shortage and high price of protein sources that are most commonly used. The aim of this analysis was to evaluate the relationship between the essential amino acids in 13 types of proteins available in the market with the essential amino acids found in the muscle of four of the most important farmed prawn species of the genus Macrobrachium (M. amazonicum, M. rosenbergii, M. americanum and M. tenellum). The results obtained showed the limiting amino acids of each ingredient for each species, thereby allowing for formulation of commercial foods that meet the nutritional needs to support optimal growth of these prawns in culture. In conclusion, there is a difference in the amino acids most often present as first limiting between sources of animal and plant origin. Thereby, it is possible evaluate complementarities between these sources to achieve an amino acids profile close to that of Macrobrachium species.

La producción de alimentos para la acuicultura requiere la búsqueda de otras fuentes o ingredientes proteínicos como alternativas potenciales en la formulación de piensos para la acuicultura, debido a la escasez y alto precio de las fuentes de proteínas utilizadas con mayor frecuencia. El objetivo de este análisis fue evaluar la relación entre los aminoácidos esenciales de 13 tipos de proteínas disponibles en el mercado con aminoácidos esenciales presentes en el músculo de cuatro de las más importantes especies de langostinos cultivadas del género Macrobrachium (M. amazonicum, M. rosenbergii, M. americanum y M. tenellum). Los resultados obtenidos muestran los aminoácidos limitantes de cada ingrediente para cada especie, lo que permite la formulación de alimentos comerciales que satisfagan las necesidades nutricionales para apoyar el crecimiento óptimo de estos langostinos en cultivo. En conclusión, existe una diferencia entre los aminoácidos que con más frecuencia se presentan como primer limitante entre las fuentes de origen animal y vegetal. De este modo, es posible evaluar complementaciones entre estas fuentes para lograr un perfil de aminoácidos cercano al de las especies de Macrobrachium.

Abstract: Seaweeds have been evaluated as feed ingredients or additives for aquatic organisms with positive results on growth performance and disease resistance. To evaluate the response of growth and feed utilization using a seaweed liquid extract (KelproidanMR), obtained from Macrocystis pyrifera as a feed additive 4% inclusion (K4%) in balanced feed (33.6% protein and 7.3% lipids) for juvenile Litopenaeus vannamei, a 45 days growth bioassay, under controlled conditions was conducted. Compared to the control treatment, the results indicate that the inclusion of KelproidanMR did not affect the zootechnical parameters of survival, growth, feed intake nor the feeding response of shrimp. In terms of feed utilization, K4% treatment significantly improved feed conversion rate, and protein efficiency (P<0.05). It was also revealed that KelproidanMR allowed two different responses in proximate composition of shrimp muscle, first increased protein content and otherwise decreased lipid content (P<0.05). In conclusion, KelproidanMR could be used as a feed additive for juvenile L. vannamei.

Resumen: Las algas marinas se han evaluado como aditivos alimentarios para organismos acuáticos con resultados positivos en las variables productivas y en la resistencia a enfermedades. En la presente investigación se evaluó un extracto líquido de Macrocystis pyrifera (KelproidanMR) al 4% de inclusión (K4%) en alimento balanceado (33.6% proteína y 7.3% lípidos) para juveniles de Litopenaeus vannamei. Se realizó un bioensayo de crecimiento durante 45 días en condiciones controladas. Comparado con el tratamiento testigo, los resultados indican que la inclusión de KelproidanMR no afectó la supervivencia, crecimiento, consumo de alimento y la respuesta alimentaria de los camarones, el tratamiento K4% mejoró la conversión alimenticia y la eficiencia proteica (P<0.05). Además, incrementó el contenido de proteína y disminuyó el contenido de lípidos del músculo en los camarones (P<0.05). Las conclusiones obtenidas en el experimento indican que el producto comercial KelproidanMR podría utilizarse como aditivo alimentario en alimentos para juveniles de camarón patiblanco del Pacífico.

El camarón blanco, Litopenaeus vannamei, es una de las especies más cultivadas comercialmente en el mundo, debido a su velocidad de crecimiento y tasa de supervivencia en altas densidades de cultivo, y su capacidad de osmoregulación, que lo hacen un excelente candidato para cultivo en diferente salinidades. El conocimiento de los requerimientos nutricionales del camarón es fundamental en la formulación de dietas que permita el crecimiento óptimo en diferentes condiciones ambientales y fases de desarrollo del animal. El efecto de la salinidad sobre la digestibilidad aparente de alimentos comerciales para camarones no está documentado. Esta información es necesaria en el cultivo de camarón para la formulación de los alimentos comerciales. Se determinó la digestibilidad aparente de los carbohidratos (ACD) y lípidos (ALD), en juveniles del camarón blanco L. vannamei cultivado en condiciones controladas. Los tratamientos fueron seis dietas comerciales (D1:37CP, D2:38CP, D3:39CP, D4:34CP, D5:35CP y D6:37CP) y dos dietas experimentales (E1:33CP y E2:33CP) para juveniles de camarón blanco en cultivo, a tres salinidades (5, 35 y 50ups) en acuarios de 60L. Los coeficientes de digestibilidad aparente de los carbohidratos (ACD) y los lípidos (ALD) fueron determinados in vivo utilizando óxido crómico como marcador inerte en la dieta. ALD en la mayoría de los tratamientos fue superior al 80%, independientemente de la salinidad, con excepción de la dieta E1:33CP que presentó 74.0% a salinidad de 50ups. La dieta D3:39CP presentó el mayor coeficiente ALD (90.1 y 90.6 en 5 y 35ups, respectivamente). En ACD, se presentaron diferencias entre dietas comerciales y experimentales en cada nivel de salinidad, aunque la salinidad no presentó un efecto significativo. La dieta D4:34CP presentó el coeficiente de digestibilidad más alto (92.4%) en la salinidad de 5ups, mientras que E2:33CP en salinidades de 35 y 50ups fue de 97.3 y 94.7%, respectivamente. En general, el presente estudio demuestra que en juveniles de camarón blanco la variación de salinidad no afecta significativamente la digestibilidad de lípidos y carbohidratos en las condiciones experimentales de este estudio.

Whiteleg shrimp, Litopenaeus vannamei is one of the most commercially farmed species worldwide because of its fast growth, good survival rate at high farming densities, and osmoregulatory capacity, which makes it an excellent candidate for cultures at different salinities. The knowledge of shrimp nutritional requirements is critical in the formulation of diets to allow optimal growth at different environmental conditions and development stages. The effect of salinity on apparent digestibility of shrimp feed is not well known, and this information is required in shrimp diet formulation. For this purpose, the apparent digestibility coefficients of carbohydrates (ACD) and lipids (ALD) were determined for juvenile whiteleg shrimps under controlled culture conditions. We evaluated the apparent digestibility of six commercial (D1:37CP, D2:38CP, D3:39CP, D4:34CP, D5:35CP, and D6:37CP) and two experimental (E1:33CP and E2:33CP) diets for juvenile whiteleg shrimp cultivated at three salinities (5, 35 and 50psu) in 60L aquariums. ACD and ALD were determined in vivo using chromic oxide as an inert marker. Our results showed that ALD in most cases was over 80%, independent of salinity, except the E1:33CPdiet which had 74.0% at 50psu. Diet D3:39CP showed the highest ALD coefficient (90.1 and 90.6% at 5 and 35psu, respectively). For ACD, differences were detected between commercial and experimental diets at every salinity level, although salinity effect on ACD was not significant. Diet D4:34CP had the highest coefficient (92.4%) at 5psu, and E2:33CP at 35 and 50psu (97.3 and 94.7%). This study demonstrated that there is no significant effect of saline variations on carbohydrate and lipid digestibility by juvenile whiteleg shrimp, under the experimental conditions. Rev. Biol. Trop. 61 (3): 1201-1213. Epub 2013 September 01.

The effect of the dietary protein level on growth and total body chemical composition of the native cichlid Bay snook (Petenia splendida), masculinized and non-masculinized, was studied. Five semi-purified diets with protein levels 35, 40, 45, 50 and 55% crude protein (CP) were formulated and evaluated by triplicate. Groups of 50 juveniles were each stocked in 70 L tanks and fed to apparent satiation for 42 days trial. At the end, weight gain (WG) (403.41%), body length (BL) (6.58 ± 0.10 cm) and specific growth rate (SRG) (1.67%/day) of the masculinized fish were obtained with the 45% CP diet, and they were significantly different (p = 0.002) from the other treatments. In the case of non-masculinized fish, the 45 and 55% CP treatments showed significant differences (p = 0.00001), with respect to other treatments, with a WG of 398 and 394%, SGR of 1.66 and 1.63%/day, protein productive value (PPV) of 28.91 and 29.21%, and feed conversion rate (FCR) of 1.23 and 1.08 respectively. Protein body composition for masculinized fish was different (p = 0.0001) only for fish fed 35% CP compared with fish at the beginning of the experiment. We conclude that the optimum protein requirement, estimated by the broken-line model for masculinized and non-masculinized P. splendida was 45 and 44.8% PC respectively.

Se evaluó el efecto del nivel de proteína sobre el crecimiento y composición química proximal del cíclido nativo tenguayaca (Petenia splendida) masculinizados y no masculinizados, para lo que se formularon cinco dietas semipurificadas con diferentes niveles de proteína cruda: 35, 40, 45, 50 y 55% PC, colocando 50 peces por tina (70 L) los cuales fueron alimentados a saciedad aparente por 42 días. Al final del periodo experimental, el mayor (p = 0.002) peso promedio (AW, 3.31 ± 0.46 g), longitud (BL, 6.58 ± 0.10 cm), ganancia en peso (WG, 403.41%) y tasa específica de crecimiento (SGR, 1.67%/día) en peces masculinizados se obtuvo para los alimentados con 45% CP. Los peces no masculinizados alimentados con las dietas de 45 y 55% CP fueron estadísticamente diferentes (p = 0.00001) en relación al WG (398 y 394%), SGR (1.66 y 1.63%/día), valor productivo de la proteína (PPV, 28.91 y 29.21%) y factor de conversión alimenticio (FCR, 1.23 y 1.08). La proteína corporal de los peces masculinizados fue estadísticamente diferente (p = 0.0001) para los peces alimentados con 35% CP comparados con los peces al inicio del experimento. Concluimos que el nivel óptimo de proteína estimado con el modelo de línea quebrada para los juveniles masculinizados y no masculinizados de P. splendida fue de 45 y 44.8% CP respectivamente.

The effect of dietary protein (31, 41, 45, and 55%) was evaluated in quadruplicate in the yellow snapper (Lutjanus argentiventris). Specimens were kept in sixteen 200 L plastic tanks for 95 days and the values of growth rate, feeding efficiency and proximate composition of yellow snapper (18 g) were examined. Every 15 days were carried out individual weight measurements and standard length of the total population. At the beginning and end of the experiment, liver and muscle samples were taken for proximate analysis of crude protein and ether extract. In general, the highest gain was obtained with fish fed with 55% crude protein in the diet. The best feed conversion ratio (FCR), specific growth rate (SGR), percent weight gain (WG%), average daily gain (ADG), and feed efficiency rate (FER) were obtained with the fish fed 55% of protein (CP). The protein content in liver decreased in fish fed with protein levels and higher energy compared with the initial fish. Finally, the use of practical diets containing 55% CP is appropriate for optimal growth and efficiency of feed utilization of yellow snapper. The results obtained in this study may be due to the early stage of development of yellow snapper where protein and energy requirements are higher.

El efecto de diferentes niveles de proteína en la dieta (31, 41, 45 y 55%) fue evaluado por cuadruplicado en el pargo amarillo Lutjanus argentiventris. Los organismos fueron mantenidos en 16 tanques de plástico de 200 L por 95 días y los valores de crecimiento, eficiencia alimenticia y composición proximal del pargo amarillo (18 g) fueron examinados. Cada 15 días se llevaron a cabo mediciones de peso individual y longitud estándar del total de la población. Al inicio y al final del experimento, muestras de hígado y músculo fueron tomadas para análisis proximal de proteína cruda y extracto etéreo. En general, la ganancia de peso más alta fue obtenida con los peces alimentados con 55% de proteína. La mejor tasa de conversión alimenticia (FCR), tasa de crecimiento específico (SGR), porcentaje de ganancia de peso (WG%), ganancia diaria promedio (ADG) y tasa de eficiencia alimenticia (FER) se obtuvo con los niveles más altos de proteína cruda. El contenido de proteína en hígado disminuyó en los peces alimentados con los niveles de proteína y energía más altos comparados con el pez inicial. Finalmente, el uso de dietas prácticas conteniendo 55% de proteína cruda es apropiado para un óptimo crecimiento y eficiencia en la utilización del alimento del pargo amarillo. El resultado obtenido en este estudio puede ser debido a la fase temprana de desarrollo del pargo amarillo, donde los requerimientos de proteína y energía son más elevados.

The effect of different feed processing methods on the physicochemical properties, and apparent digestibility of cowpea (Vigna unguiculata) meals as ingredients in diets for white shrimp (Litopenaeus vannamei) was investigated. Five experimental cowpea meals were prepared: whole raw (WRC), dehulled (DC), cooked (CC), germinated (GC) and extruded (EXC). The physicochemical properties of the meals were evaluated using differential scanning calorimetry. The meals were included at 15% in diets for L. vannamei (15.4 g) to determine firmness of pellets and in vivo digestibility of nutrients by using chromic oxide as inert marker. Six diets were evaluated: a control diet, and five diets containing the different cowpea meals. Transition enthalpy significantly decreased after thermal treatment, from 6.1 J/g in WRC to 1.4 J/g in CC, and disappeared in EXC. Firmness of pellets varied from 1.1 N in the EXC diet to 2.8 N in the WRC diet. A significant negative correlation between transition enthalpy and carbohydrate digestibility was found. Dry matter, protein, carbohydrate and lipid digestibility of cowpea meals significantly increased after germinating, cooking or extruding. It is concluded that germinated, cooked and extruded cowpea meals are highly digestible for shrimp and that enthalpy of transition is negatively correlated with the digestibility of carbohydrates.

Se evaluó el efecto de diferentes procesos sobre las propiedades fisicoquímicas y digestibilidad aparente de la harina de frijol yorimón (Vigna unguiculata) como ingrediente en alimentos para camarón blanco (Litopenaeus vannamei). Se elaboraron cinco harinas de frijol yorimón: entero crudo (WRC), decorticado (DC), cocido (CC), germinado (GC) y extruido (EXC). Las características térmicas de las harinas fueron evaluadas usando calorimetría diferencial de barrido. Se elaboraron seis alimentos experimentales: un alimento control y cinco alimentos conteniendo 15% de las diferentes harinas de frijol yorimón. A estos alimentos se le determinó firmeza y digestibilidad in vivo de nutrientes para L. vannamei (15.4 g) usando óxido de cromo como marcador inerte. La entalpía de transición decreció después del tratamiento térmico, de 6.1 J/g en la WRC a 1.4 J/g en la CC, y desapareció en la EXC. La firmeza de los alimentos varió de 1.1 N en el alimento con EXC a 2.8 N en el alimento con WRC. Se encontró una correlación significativa negativa entre la entalpía de transición y la digestibilidad de carbohidratos de la harina del frijol yorimón. La digestibilidad de materia seca, proteína, carbohidratos y lípidos de las harinas de frijol yorimón aumentó significativamente con el germinado, la cocción y la extrusión. En el presente estudio se concluye que las harinas de frijol yorimón germinado, cocido y extruido son altamente digeribles para camarón L. vannamei, y la entalpía de transición se correlaciona significativamente con la digestibilidad de los carbohidratos.

An experiment was conducted at the wet laboratory of the Fisheries Research Centre, Havana, Cuba, to evaluate the attractability of a pelleted diet containing Spirulina platensis meal for Litopenaeus schmitii juvenile. The design was completely randomized with 4 treatments and 6 repetitions. Two diets: a diet containing 5% of Spirulina platensis meal and a control diet without it, and two positions of the feed were assayed inside an experimental device consisting in a rectangular glass aquarium in which two internal glass walls were placed in order to have three equal sections. Ten shrimps with mean weight of 0.503 ± 0.018 g were placed in the central section of the aquarium, with access to the other two sections, where the experimental diets were placed. A bifactorial analysis showed that the attraction was significatly affected by type of feed, although the position did not have any significant effect. A greater percentage of shrimp (68%) moved toward the position where the diet containing Spirulina platensis meal was placed, and ingested the diet. It is concluded that the inclusion of 5% of Spirulina platensis meal improved the attractability of the feed for Litopenaeus schmitti.

Con el objetivo de conocer el poder atrayente de la harina de Spirulina platensis como aditivo en la alimentación de Litopenaeus schmitti, se realizó un experimento en el laboratorio húmedo del Centro de Investigaciones Pesqueras, La Habana, Cuba, con un diseño totalmente aleatorizado (4 tratamientos con 6 repeticiones) donde se ensayaron 2 alimentos: uno con 5% de Spirulina platensis, y un control sin la microalga, y dos posiciones del alimento dentro de un dispositivo experimental consistente en un acuario rectangular al que se le colocaron dos divisiones de vidrio, que permitieron que el acuario quedara dividido en tres compartimentos iguales. Diez camarones con una masa promedio de 0.503 ± 0.018 g se colocaron en la sección central, con acceso a los otros dos compartimentos del acuario, en los cuales se situaron los alimentos experimentales. Un análisis bifactorial mostró que el tipo de alimento influyó significativamente en la atracción y que la posición no tuvo efecto significativo alguno, aunque hubo interacción entre los factores. El mayor porcentaje de camarones (68%) se desplazó a la posición donde se encontraba el alimento con inclusión de harina de Spirulina platensis y lo ingirió. Se concluye que la adición de 5% de harina de Spirulina platensis mejora la atractabilidad del alimento para Litopenaeus schmitti.

Apparent dry matter and protein digestibility of four animal and three vegetal ingredients and diets with them included, were evaluated for pre-adult Cherax quadricarinatus. The ingredients were: two sardine meals (67% and 58% crude protein), squid meal, red crab meal, soy paste, textured wheat, and sorghum meal. A reference and seven experimental diets were formulated including 14.5% of each ingredient in the reference diet, and 0.5% of chromic oxide as a marker. Vegetal ingredients and the corresponding diets, had higher digestibility than animal ingredients. Textured wheat, soy paste, and sorghum meals showed an excellent dry matter/digestibility (> 86%). The digestibility of protein was better in textured wheat, and soy paste meals (> 87%). Some animal ingredients such as, squid meal, and sardine meal 67% CP, had acceptable dry matter digestibility (over 65%). It is concluded that pre-adult redclaw is omnivorous and able to efficiently consume vegetal and animal ingredients, but they can digest better the vegetal ingredients.

La digestibilidad aparente de proteínas y de materia seca de cuatro ingredientes animales y tres ingredientes vegetales, así como de las dietas en que se incluyeron, fueron evaluados para pre-adultos del acocil australiano Cherax quadricarinatus. Los ingredientes probados fueron: dos harinas de sardina (67% y 58% de proteína cruda), harina de calamar, harina de langostilla, pasta de soya, trigo texturizado y harina de sorgo. Una dieta de referencia y siete dietas experimentales fueron formuladas, incluyendo 14.5% de cada ingrediente en la dieta de referencia y 5% de óxido crómico como marcador. Los ingredientes vegetales y sus respectivas dietas, tuvieron más alta digestibilidad que los ingredientes animales y sus dietas. El trigo texturizado, la pasta de soya y la harina de sorgo, presentaron una excelente digestibilidad de materia seca (> 86%). La digestibilidad proteica fue mejor para el trigo texturizado y la pasta de soya (>87%). Algunos ingredientes animales como la harina de calamar y harina de sardina con 67% de proteína cruda, tuvieron una aceptable digestibilidad de materia seca (>65%). Se concluye que el acocil australiano, en su fase de pre-adulto, es un organismo omnívoro capaz de consumir eficientemente ingredientes de origen vegetal y animal, pero que digiere mejor los de origen vegetal.