Dietary biodiesel-derived crude glycerol in gilthead seabream juveniles (Sparus aurata): effects on growth performance and metabolism

In the European Union the turn towards renewable energy sources has increased the production of biodiesel from rapeseed oil, leaving glycerol (also known as glycerin) as a valuable by-product. For every litre of biodiesel produced, approximately 79 g of crude glycerol are generated. As the biodiesel production grows, the quantity of crude glycerol generated will be considerable and its utilization will become an urgent topic. One possibility is the use of crude glycerol on animal feeds. Glycerol has been evaluated as a dietary energy source for several farm animals, including fish. A study was undertaken to assess the effect of dietary biodiesel-derived glycerol (from rapeseed oil) on the overall growth performance, digestive capacity and metabolic nutrient utilization in juvenile gilthead seabream fed a low fishmeal level diet. Two practical diets were formulated to be isonitrogenous (crude protein, 45.4% DM), isolipidic (18.5% DM) and isoenergetic (gross energy, 21.3 kJ/g DM). The control diet (CTRL) was formulated with intermediate levels of marine-derived proteins (19%). In the same basal formulation, 5% glycerol (GLY) was incorporated at the expenses of wheat. Each dietary treatment was tested in triplicate tanks over 63 days, with 20 gilthead seabream (Sparus aurata), with a mean initial body weight (IBW) of 27.9 0.12 g. At the end of the trial, fish fed the CTRL diet reached a final body weight of 84.3 2.2 g (more than 3-fold increase of initial body weight). Fish fed the GLY diet showed a significantly higher (P<0.05) growth, expressed in terms of final body weight and specific growth rate. Voluntary feed intake was similar between the two treatments, but both feed efficiency and protein efficiency ratio were significantly improved (P0.05) on the apparent digestibility of protein. In comparison to the control treatment, dietary glycerol significantly improved (P<0.05) protein and fat retention. Activities of digestive enzymes were significantly affected by the various dietary treatments. Fish fed the GLY diet showed an enhanced activity of alkaline phosphatase (ALP) and pepsin, while activities of lipase and leucine-alanine peptidase (LAP) were little affected by dietary glycerol. Fish show the ability to use crude glycerol as a dietary energy substrate.Na União Europeia, tem-se verificado uma procura crescente de novas fontes de energia renováveis, o que tem conduzido a um aumento da produção de biodiesel a partir de óleo de colza, originando o glicerol (também conhecido como glicerina) como um valioso subproduto. Por cada litro de biodiesel produzido, são geradas aproximadamente 79 g de glicerol bruto. À medida que a produção de biodiesel aumenta geram-se quantidades consideráveis de glicerol tornando-se urgente encontrar soluções adequadas à utilização deste excedente. Uma alternativa possível é a utilização de glicerol bruto na formulação de rações para animais. O glicerol tem sido estudado como fonte de energia nas dietas de diferentes animais, incluindo peixes. O presente trabalho descreve um estudo efectuado para avaliar o efeito da incorporação de glicerol bruto derivado da produção de biodiesel (a partir de óleo de colza) em dietas, com baixo teor em farinha de peixe, para juvenis de dourada (Sparus aurata). Os principais parâmetros avaliados foram o desempenho global de crescimento, a capacidade digestiva e a utilização metabólica de nutrientes. Duas dietas práticas foram formuladas para serem isoproteicas (proteína bruta, 45,4% de MS), isolipídicas (18,5% de MS) e isoenergéticas (energia bruta, 21,3 kJ / g MS). A dieta de controlo (CTRL) foi produzida com níveis intermédios de derivados de proteínas marinhas (19%). A partir da mesma formulação base, 5% de glicerol foi incorporado em detrimento do trigo obtendo-se a dieta glicerol (GLY). Os tratamentos foram testados em triplicado durante 63 dias, em grupos de 20 douradas com um peso médio inicial (PI) de 27,9 0,12 g. No final do ensaio, os peixes alimentados com a dieta CTRL atingiram um peso final (PF) de 84,3 2,2 g, triplicando o seu peso inicial. Os peixes alimentados com a dieta GLY mostraram um crescimento significativamente superior (P <0,05) em termos de peso final e taxa de crescimento específico. A ingestão de alimento foi similar entre os dois tratamentos, mas quer a eficiência alimentar quer o coeficiente de eficácia proteica melhoraram significativamente (P <0,05) nos peixes alimentados com a dieta GLY. A incorporação de glicerol na dieta não teve efeito (P> 0,05) sobre a digestibilidade aparente da proteína. Em comparação com o tratamento de controlo, o glicerol melhorou significativamente (P <0,05) a retenção de proteína e de gordura. A atividade dos enzimas digestivos foi significativamente alterada pelos diferentes tratamentos. Peixes alimentados com a dieta GLY mostraram um aumento da atividade da fosfatase alcalina (ALP) e da pepsina, enquanto a atividade da lipase e da leucina-alanina peptidase (LAP) foram pouco influenciadas pelo glicerol na dieta. A dourada demonstrou uma boa capacidade de utilizar glicerol bruto como uma fonte energética fornecida pela dieta

Núcleos de Ensino da Unesp: artigos 2008

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

NEOTROPICAL CARNIVORES: a data set on carnivore distribution in the Neotropics

Mammalian carnivores are considered a key group in maintaining ecological health and can indicate potential ecological integrity in landscapes where they occur. Carnivores also hold high conservation value and their habitat requirements can guide management and conservation plans. The order Carnivora has 84 species from 8 families in the Neotropical region: Canidae; Felidae; Mephitidae; Mustelidae; Otariidae; Phocidae; Procyonidae; and Ursidae. Herein, we include published and unpublished data on native terrestrial Neotropical carnivores (Canidae; Felidae; Mephitidae; Mustelidae; Procyonidae; and Ursidae). NEOTROPICAL CARNIVORES is a publicly available data set that includes 99,605 data entries from 35,511 unique georeferenced coordinates. Detection/non-detection and quantitative data were obtained from 1818 to 2018 by researchers, governmental agencies, non-governmental organizations, and private consultants. Data were collected using several methods including camera trapping, museum collections, roadkill, line transect, and opportunistic records. Literature (peer-reviewed and grey literature) from Portuguese, Spanish and English were incorporated in this compilation. Most of the data set consists of detection data entries (n = 79,343; 79.7%) but also includes non-detection data (n = 20,262; 20.3%). Of those, 43.3% also include count data (n = 43,151). The information available in NEOTROPICAL CARNIVORES will contribute to macroecological, ecological, and conservation questions in multiple spatio-temporal perspectives. As carnivores play key roles in trophic interactions, a better understanding of their distribution and habitat requirements are essential to establish conservation management plans and safeguard the future ecological health of Neotropical ecosystems. Our data paper, combined with other large-scale data sets, has great potential to clarify species distribution and related ecological processes within the Neotropics. There are no copyright restrictions and no restriction for using data from this data paper, as long as the data paper is cited as the source of the information used. We also request that users inform us of how they intend to use the data