Apparent digestibility of ingredients in diets for Salminus brasiliensis

The objective of this work was to determine the nutritional value of different protein sources for "dourado" (Salminus brasiliensis). Thirty juveniles per group (33.51±1.4 g) were hand fed on a reference diet (70%) added of tested ingredients (30%) and chromium oxide III (0.1%). Apparent digestibility coefficients of the gross energy (ADC GE), crude protein (ADC CP) and amino acids of the tested ingredients were evaluated. Corn gluten meal yielded the best results for ADC GE and ADC CP (95.7 and 96.9%, respectively) amongst plant ingredients. Spray-dried blood meal yielded the best values of ADC GE and ADC CP amongst animal ingredients (94.1 and 96.3%, respectively). Wheat bran yielded poorest ADCs coefficients (77 for ADC GE and 88.2% for ADC CP).

Mortality of Plutella xylostella larvae treated with Aspidosperma pyrifolium ethanol extracts

The objective of this work was to assess the effects of Aspidosperma pyrifolium ethanol extracts on cabbage moth (Plutella xylostella) larvae. The ethanol extracts of the stem bark, fruits and roots of A. pyrifolium were obtained by classical phytochemical methods, and the resulting subfractions were tested on P. xylostella, using 4 and 5 mg L-1. The crude ethanol extract of the stem bark was more lethal. The alkaloid-rich aqueous subfraction derived from the stem bark extract caused 100% larval mortality at 4 mg L-1. Insecticidal activity was associated with the presence of the monoterpenoid indole alkaloids aspidofractinine, 15-demethoxypyrifoline, and N-formylaspidofractinine. These alkaloids presented excellent insecticidal properties against P. xylostella.

Growth performance and body composition of giant trahira fingerlings fed diets with different protein and energy levels

The objective of this work was to determine the proper levels of protein and energy in diets of Hoplias lacerdae fingerlings. The dietary crude protein (CP) and gross energy (GE) levels for fingerlings of giant trahira were evaluated in a completely randomized 4x3 factorial design with 35, 39, 43 and 47% CP and 4,100, 4,300 and 4,500 kcal kg-1 of GE, and four replicates. The survival rate was 99.22%, and a linear improvement on the performance parameters was detected after increasing diet crude protein levels. Feed conversion ratio decreased with increasing levels of dietary protein and energy in the diets. A significant interaction between crude protein and gross energy was observed over body protein and mineral matter. Body lipid has increased linearly as gross energy in the diet increased. The retention of crude protein and energy showed a linear increasing with rising of crude protein levels in the diet. Crude protein level at 47% provides the best performance and energy retention, independently of the gross energy levels in the diet.

Performance of juveniles of Pseudoplatystoma fasciatum fed graded levels of corn gluten meal

The objective of this work was to evaluate corn gluten meal (CGM) as a substitute for fish meal in diets for striped catfish (Pseudoplatystoma fasciatum) juveniles. Eight isonitrogenous (46% crude protein) and isoenergetic (3,450 kcal kg-1 digestible energy) diets, with increasing levels of CGM - 0, 6, 12, 18, 24, 30, 36, and 42% -, were fed to juvenile striped catfish (113.56±5.10 g) for seven weeks. Maximum values for weight gain, specific growth rate, protein efficiency ratio and feed conversion ratio, evaluated by polynomial quadratic regression, were observed with 10.4, 11.4, 15.4 and 15% of CGM inclusion, respectively. Feed intake decreased significantly from 0.8% CGM. Mesenteric fat index and body gross energy decreased linearly with increasing levels of CGM; minimum body protein contents were observed with 34.1% CGM. Yellow pigmentation of fillets significantly increased until 26.5% CGM, and decreased from this point forth. Both plasma glucose and protein concentrations decreased with increased CGM levels. The inclusion of 10-15% CGM promotes optimum of striped catfish juveniles depending on the parameter evaluated. Yellow coloration in fillets produced by CGM diets can have marketing implications.

Growth and hematology of pacu subjected to sustained swimming and fed different protein levels

The objective of this work was to evaluate the effect of sustained swimming and dietary protein levels on growth and hematological responses of juvenile pacu (Piaractus mesopotamicus). A completely randomized design was used in a 3x2 factorial arrangement, with three levels of dietary protein (24, 28, and 32% crude protein), two rearing conditions (sustained swimming or motionless water), and 15 replicates. Fish were subjected to sustained swimming at the velocity of two body lengths per second (2 BL s-1), for 45 days. The level of dietary protein and the swimming conditions affected the performance, growth, and hematological profile of pacu. Swimming conditions influenced nutritional factors, increasing daily weight gain, specific growth rate, number of erythrocytes, mean corpuscular volume, and mean corpuscular hemoglobin. Fish under sustained swimming and fed with 24% crude protein showed better growth performance, with higher specific growth rate (4.11±0.88) and higher daily weight gain (2.19±0.47 g per day). Sustained swimming can increase the productive performance of pacu and simultaneously reduce dietary protein levels.

Growth and stress of dourado cultivated in cages at different stocking densities

The objective of this work was to evaluate the growth and the stress levels of juvenile dourado (Salminus brasiliensis) cultivated in cages. Fish stocked at densities of 15 (D15) and 30 (D30) fish per square meter were evaluated in a completely randomized design with three replicates. Fish were fed twice a day with extruded ration (42% crude protein). Density influenced only biomass and daily food intake, and glucose and lactate concentrations increased over time. D15 and D30 did not influence the growth of dourado. However, the increase of glucose and lactate levels over time indicates that cultivation in cages is a stressful condition for this species.

Feed intake and growth performance of goats supplemented with soy waste

The objective of this work was to evaluate the effects of supplemental feeding of soy waste on the feed intake and growth rate of goats. Twenty male crossbred (Boer x local) goats were assigned to two isonitrogenous diet groups: one of commercial pellet and the other of soy waste. The commercial pellet (1.0%) and soy waste (0.8%) were provided on the dry matter basis of body weight (BW) per day, to the respective group of each diet. The soy waste group had lower daily intakes of total dry matter (0.79 vs. 0.88 kg) and organic matter (665.71 vs. 790.44 g) than the group fed pellet; however, the differences on daily intakes for grass (0.62 vs. 0.64 kg), crude protein (96.81 vs. 96.83 g), and neutral detergent fibre (483.70 vs. 499.86 g) were not significant. No differences were observed between groups for BW gain. The feed conversion ratio and feed cost per kilogram of BW gain were lower for the group fed soy waste than for the one fed pellet. Goats fed supplemental soy waste have a lower total dry matter intake, feed conversion ratio, and feed cost per kilogram of body weight gain than those fed commercial pellets.

Protein contamination on Klason lignin contents in tropical grasses and legumes

The objective of this work was to evaluate the extent of protein contamination on Klason lignin (KL) in tropical grasses and legumes, and to propose an equation to estimate the protein-free content of Klason lignin (KLp). Five grass (30 samples) and 12 legume species (31 samples) were evaluated. Legumes had higher KL contents. Protein contamination was significant in both grasses and legumes, but greater in legume samples. The model to predict KLp was based on KL and crude protein (CP) contents, as follows: KLp = 0.8807KL - 0.0938KL x D - 0.00338CP (R2=0.935), in which D=0, for grasses, and D=1 for legumes.

Apparent digestibility of nutrients, energy, and amino acid of nontoxic and detoxified physic nut cakes for Nile tilapia

Abstract:The objective of this work was to evaluate the apparent digestibility coefficients of nutrients, energy, and amino acids of nontoxic and detoxified physic nut cakes treated with solvent plus posterior extrusion, for Nile tilapia. The apparent digestibility coefficients of crude protein and gross energy were higher for detoxified than for nontoxic physic nut cake. However, the apparent digestibility coefficient of ether extract of the nontoxic physic nut cake was higher than that of the detoxified one. The apparent digestibility coefficient of amino acids of both feed ingredients was superior to 80%, except for glycine, for the nontoxic psychic nut cake, and for threonine, for the detoxified one. Nontoxic and detoxified physic nut cakes show apparent digestibility coefficient values equivalent to those of the other evaluated oilseeds and potential for inclusion in Nile tilapia diets.

Aplicação de pigmentos de flores no ensino de química

In the present work, the pH dependent colour change of the crude flower extracts is suggested as subject in teaching chemical or acid-base equilibria, visual indicators and some aspects of spectrophotometric concepts and applications. The vegetal species used are commonly found in Brazil, and the extraction methodology proposed is inexpensive and easy to perform in secondary schools and in general chemistry or instrumental undergraduate courses. A bibliographic review about the use of vegetal extracts in chemical education and a discussion of the flower colour are also presented.

Cinética não-isotérmica na análise térmica de sólidos

In this work, a computer program called Thermal Kinetics was implemented to simulate thermal analysis experiments by numerical integration of the kinetics equations. The computer program was tested in two different examples: non-isothermal transformation of a Cu-Al alloy and non-isothermal decomposition of calcium oxalate monohydrated. In spite of the rather crude approximations of the model, the simulated profiles are very similar to the experimental curves. Both, the dalpha /dt and the dalpha /dT profiles reproduce the experimental transition temperatures with an error smaller than 25%.

Análise de naftoquinonas em extratos brutos de raízes de Zeyheria montana M. (bolsa-de-pastor)

Four naphthoquinones, lapachol, a-lapachone, dehydro-a-lapachone and 4-hydroxy-a-lapachone were isolated from the ethanol extract of Zeyheria montana M. roots (Bignoniaceae) and were identified by spectroscopic methods. These naphthoquinones, except 4-hydroxy-a-lapachone, were quantified by HPLC, in the crude ethanol extracts of Z. montana roots. The separation of lapachol, a-lapachone and dehydro-a-lapachone was achieved and these compounds were identified in the chromatograms by their retention times and by their on line UV-spectra. The quantification of the three naphthoquinones, in four different samples showed medium contents of 11,0 mg of lapachol, 6,1 mg of a-lapachone and 4,3 mg of dehydro-a-lapachone, in 100 mg of Z.montana roots.

Aplicação de extratos brutos de flores de quaresmeira e azaléia e da casca de feijão preto em volumetria ácido-base. Um experimento para cursos de análise quantitativa

Crude extract of Tibouchina granulosa, Rhododendron simsii and Phaseolus vulgaris L. were prepared and used as alternative indicators in quantitative analysis teaching in standardization of NaOH solutions and in the determination of acetic acid contents in vinegar. Effect of using such natural extracts as indicators was very attractive to the students and the quantitative results were compared with conventional indicators with good agreement. Concepts of data statistics can successfully be discussed using the interest revived by the use of natural indicators.

Uso analítico de tecidos e de extratos brutos vegetais como fonte enzimática

This article describes the current status of several analytical methodologies using vegetal tissue and crude extracts as enzymatic source. In this divulgation paper the obtention of vegetal crude extract and/or tissue and selected enzymatic procedures are presented emphasizing its characteristics and peculiarities. Examples of many biosensors and/or flow injection procedures using vegetal tissues or crude extracts for the determination of many analytes, such as amines, ascorbic acid, ethanol, glutamate, hydrogen peroxide, oxalic acid, pectins, phenolic compounds and urea of biologic, environmental, food, pharmaceutical and industrial interests are also given and discussed.

Identificação de pigmentos naturais de espécies vegetais utilizando-se cromatografia em papel

The use of natural dyes to demonstrate principles of paper chromatography is proposed. Extraction of the coloring compounds were performed in order to obtain the aglycone form of the anthocyanins present in the crude extracts. Separations were carried out on chromatographic paper with BAW (butanol/acetic acid/water) as mobile phase and the results compared with literature data. The crude extracts were obtained from Tibouchina granulosa, Rododhendron simsii, Impatiens walleriana flowers which are wildely found in Brazil and Phaseolus vulgaris L. grains skin which is the principal ingredient of the world famous "feijoada". Such species were chosen in order to attract the students attention since they are present in their quotidian, in agreement with the new proposals for Brazilian education.