Crecimiento y mejora del índice gonadal en el cultivo del erizo de mar Paracentrotus lividus (Echinoida: Echinidae) en Galicia (España) / Growth rate and gonadal index improvement in sea urchin culture Paracentrotus lividus (Echinoida: Echinidae)

Resumen La gran demanda de Paracentrotus lividus (Lamarck, 1816) en países como Francia, Italia, Turquía, Bélgica o Japón, ha elevado el nivel de extracción de este equinodermo en los últimos años que ha generado un desgaste en las poblaciones de erizos, los cuales tardan años en regenerarse. La importancia económica de P. lividus en Galicia, con una producción media anual de 700 000 kg y un valor cercano a los 2 millones de € en el año 2013, nos ha llevado a realizar diversas experiencias con el objetivo de analizar las posibilidades del cultivo en Galicia de esta especie en batea. Se han diseñado tres experiencias: 1) Efecto de cinco dietas y tres densidades sobre el crecimiento de juveniles de P. lividus obtenidos del medio natural; (2) Crecimiento de juveniles de P. lividus obtenidos en criadero, alimentados con algas, y 3) Efecto de diferentes dietas experimentales sobre el índice gonadal de P. lividus de tamaño comercial. Las experiencias se realizaron en una batea de la USC situada en la ría de Muros-Noia (Galicia), durante cuatro años (2007 - 2010), utilizando 2 231 erizos en total, procedentes del medio natural (450), de criadero (773) y de tamaño comercial (1 008), diseñándose diversas dietas experimentales que tratan de incrementar el crecimiento somático y gonadal de los erizos, con el fin de reducir el tiempo de crecimiento de los juveniles procedentes del medio natural y de criadero hasta que alcancen la talla comercial (55 mm de diámetro), o bien hasta que consigan un tamaño adecuado para repoblar las zonas sobreexplotadas del medio natural (20 mm de diámetro), así como el crecimiento de las gónadas de erizos comerciales con diferentes dietas. Mensualmente se tomó el diámetro de los erizos juveniles con el fin de determinar el efecto de las diferentes dietas y densidades sobre el crecimiento de los mismos, así como la determinación del índice gonadal (IG) en los erizos de tamaño comercial para ver el efecto de las diferentes dietas ensayadas. Con los datos obtenidos estimamos que, en la actualidad, no sería rentable alimentar erizos juveniles de P. lividus en batea hasta alcanzar la talla comercial, debido al bajo precio que tiene esta especie en el mercado (3€ / kg aproximadamente), aunque sí sería interesante mantenerlos en cultivo en batea hasta que alcancen el tamaño óptimo para repoblar zonas donde las poblaciones naturales están mermadas, combinando esto con el engorde de gónadas con alguno de los piensos diseñados que aumenta el IG y amplía el tiempo de explotación comercial de los erizos.

Abstract The high demand for Paracentrotus lividus (Lamarck, 1816) in countries like France, Italy, Turkey, Belgium and Japan, has raised the level of extraction of this echinoderm in recent years and has generated wear urchin populations, which take years to regenerate. The economic importance of P. lividus in Galicia, with an average annual production of 700≤000 kg and a value close to € 2 million in 2013, has led us to perform a variety of experiences in order to analyze the possibilities of the culture of this species in Galicia in raft. We have designed three experiences: 1) Effect of five diets and three densities on the growth of juvenile P. lividus obtained from the natural environment; 2) Growth of juvenile P. lividus obtained from hatchery, fed algae, and 3) Effect of different experimental diets on gonadal index of P. lividus commercial size. The experiments were performed on a USC raft situated in the estuary of Muros-Noia (Galicia) for four years (2007 - 2010), using 2 231 total urchins, from the natural environment (450), hatchery (773) and market size (1 008), being designed various experimental diets that try to increase somatic and gonadal growth in sea urchins, in order to reduce the rise time of juveniles from the wild and hatchery until they reach the size commercial (55 mm diameter), or until they get a suitable size to repopulate overfished areas of the natural environment (20 mm diameter), and the growth of the gonads of sea urchins with different diets. Monthly has taken diameter of juvenile sea urchins in order to determine the effect of different diets on growth and densities of the same, as well as determining the gonadal index (GI) in sea urchins of commercial size to see the effect took different tested diets. With the data obtained estimates that, at present, it would be profitable to feed juvenile sea urchins P. lividus in raft to reach commercial size, due to the low price of this species in the market (3€ / kg). Additonally they could reach optimum size and be used to repopulate areas where natural populations are depleted. This should be combined with the fattening of gonads and extended time of commercial exploitation. Rev. Biol. Trop. 63 (Suppl. 2): 261-272. Epub 2015 June 01.

Comparative study of fenugreek seeds on glycemic index in high and medium dietary fiber containing diets in NIDDM patients.

Background: Several studies have reported the hypoglycemic property of Fenugreek seeds (Trigonella foenum graecum), a commonly used condiment in Indian homes, due to its high dietary fiber content. Method: A total of 25 NIDDM patients were given control diets orally consisting of (i)milled rice(boiled rice),(ii) whole wheat (chapati) experimental diets consisting of (iii) boiled rice with fenugreek seed powder and (iv) chapati with fenugreek seed powder given on four consecutive days. Blood was collected at 0, 15, 30,45,60,90 and 120 minutes. Area under curve and glycemic index was calculated for both control and experimental diets. Results: The mean of area under curve of rice with fenugreek and wheat with fenugreek are significantly lower when compared with only rice and only wheat taken orally respectively. Further, the mean glycemic index was significantly lower when fenugreek was given 15 minutes before meal compared to fenugreek given along with meal. Conclusion: Fenugreek has a lowering effect on glycemic index when added to rice and wheat diets, due to delayed gastric emptying and increased intestinal transit time. In addition, fenugreek decreases glucose absorption and inhibits starch digestion due to presence of soluble fiber and galactomannans. Adding fenugreek to the diet of diabetes patients 15 minutes before the meal causes a significant reduction in glycemic index and is beneficial to NIDDM patients for long term control of their blood glucose levels and prevention of hyperglycaemia related complications.

Avaliação in vivo da qualidade protéica do champignon do Brasil (Agaricusbrasiliensis Wasser et al. ) / In vivo protein quality evaluation of champignon do Brasil (Agaricus brasiliensis Wasser et al. )

OBJETIVO: O trabalho aqui descrito trata da avaliação de uma dieta experimental contendo Champingnon do Brasil (Agaricus brasiliensis) como fonte de proteína em um modelo experimental de ratos. MÉTODOS: Para este propósito, foram selecionados 24 ratos Wistar machos, recém desmamados (21 dias) divididos em 3 grupos de 8 animais cada, que foram alimentados com uma dieta padrão de caseína, ou com uma dieta experimental de proteína de Agaricus brasiliensis ambas contendo 10% de proteína e isoenergéticas ou ainda, com uma dieta com muito baixo teor de proteína. O ensaio biológico foi realizado em 28 dias, ao longo dos quais se determinou a concentração de nitrogênio na urina e nas fezes, além dos cálculos do Quociente de Eficiência Alimentar (ganho de peso dividido pelo consumo de dieta), do Quociente de Eficiência Protéica (ganho de peso dividido pelo consumo de proteína), da Razão Protéica Líquida (ganho de peso corrigido dividido pelo consumo de proteína) e da Digestibilidade Verdadeira. RESULTADOS: Os resultados demonstraram que quando o Champignon do Brasil foi utilizado como fonte exclusiva de proteína na dieta, os índices de qualidade protéica apresentaram-se baixos (Quociente de Eficiência Alimentar=0,08, Quociente de Eficiência Protéica=0,92 e Razão Protéica Líquida=3,00), quando comparados com a dieta padrão caseína (Quociente de Eficiência Alimentar=0,30, Quociente de Eficiência Protéica=3,05 e Razão Protéica Líquida=4,21). Os índices obtidos para o grupo Agaricus mostraram-se comparáveis àqueles apresentados por alguns tipos de proteína vegetal e podem ser explicados por sua limitação em aminoácidos essenciais, notadamente a lisina e a leucina, respectivamente primeiro e segundo aminoácido limitante. CONCLUSÃO: Os dados apontam para a utilização da proteína do Agaricus brasiliensis como uma boa fonte para complementação protéica, quando combinada com outras culturas vegetais comuns na dieta típica brasileira.

OBJECTIVE: The present work describes the biological evaluation of an experimental diet containing Champingnon do Brasil (Agaricus brasiliensis) as the main protein source for a rat experimental model. METHODS: For this purpose, 24 21-day-old male Wistar rats were divided into 3 groups of 8 animals each and were fed with a standard casein diet or an experimental Agaricus diet both with 10% protein and isoenergetic or a very low protein diet. A biological assay was done for 28 days by determining the concentration of nitrogen in the urine and stools and calculating the Food Efficiency Ratio (weight gain divided by food intake), Protein Efficiency Ratio (weight gain divided by protein intake), Net Protein Ratio (corrected weight gain divided by protein intake) and True Digestibility. RESULTS: The results showed that when Champignon do Brasil was used as the only source of protein in the diet, the Protein Quality indices were low (Food Efficiency Ratio=0.08, Protein Efficiency Ratio=0.92 and Net Protein Ratio=3.00) when compared with the standard casein diet (Food Efficiency Ratio=0.30, Protein Efficiency Ratio=3.05 and Net Protein Ratio=4.21). The indices obtained for Agaricus were comparable to some plant protein sources and can be explained by the first and second limiting amino acids, lysine and leucine, respectively. CONCLUSION: The data show that Agaricus brasiliensis is a good source of protein when combined with other vegetables that are common in the typical Brazilian diet.