Elton Lima Santos

Desempenho de alevinos de tilápia do Nilo alimentados com folha de mandioca desidratada na dieta

ABSTRACTThe aim was to evaluate the growth and the economic viability of the Nile tilapia (Oreochromis niloticus) fed with different levels of dehydrated cassava leaf flour in the diet (FFMD). 80 fingerlings were distributed into 20 18L containers, consisting of a water recirculation system over a period of 51 days. 100 copies fed three times a day to satiation were randomly assigned in a completely randomized design, constituting 4 treatments (0%, 5%, 10% and 15% addition of FFMD in diet) with 5 repetitions each. The fishes fed with 10% FFMD had better homogeneity in growth. However, individuals fed with inclusion of 5% FFMD homogeneity grew similarly to those fed with 10% FFMD. In addition, the fish from the 5% had better growth performance and economic viability of the feed. Thus, it is recommended to use 5% of dehydrated cassava leaf meal in diets for Nile tilapia.

EFFECT OF THE ENVIRONMENTAL COLOR ON THE SOCIAL BEHAVIOR OF MALES OF BETTA SPLENDENS

O presente trabalho teve como finalidade a avaliacao do comportamento social de Betta splendens submetidos a ambientes com diferentes cores. A pesquisa teve duracao de 60 dias de experimentacao, onde foram utilizados 18 Bettas splendens, machos, distribuidos individualmente em 18 aquarios experimentais de 1,5 L de capacidade efetiva, sendo utilizados seis tratamentos, que foram as cores do ambiente (aquario), constando de: T1 – cor branca, T2 – cor verde, T3 – cor azul, T4 – cor vermelho, T5 – cor amarela e T6 – cor preta com tres repeticoes cada, e um animal para cada unidade experimental, dispostos num delineamento inteiramente casualizado em parcelas subdivididas. Em todos os tratamentos, nos dias de alimentacao, foi ofertada racao duas vezes ao dia (manha e tarde) em horarios pre-determinados, ate a aparente saciedade dos animais. A racao utilizada foi comercial especifica para a especie, com os mesmos padroes nutricionais em todos os tratamentos. Os parâmetros avaliados foram a Distribuicao na lâmina d’agua; Atividade locomotora; Confronto agonistico; Confronto agonistico com ameaca; Posicao da nadadeira dorsal e Abertura dos operculos. A coleta de dados foi realizada semanalmente de acordo com um padrao pre-estabelecido de comportamento. Os resultados obtidos foram submetidos a ANAVA e teste de Tukey a 5% de probabilidade. A cor do ambiente em aquarios experimentais influencia o comportamento social dos Bettas, sendo as cores branco e azul mais recomendadas a manutencao da especie, por amenizarem as interacoes agonisticas e o estresse.

Exigência de proteína bruta para juvenis de curimatã-pacu

The aim of this study was to determinate crude protein (CP) requirement to curimatã-pacu juveniles (Prochilodus argenteus). The experiment was conducted during 60 days in a completely randomized design, with four treatments (24.0, 28.0, 32.0 and 36.0% CP of diet) and five replications, where a hundred juvenile fishes (initial weight de 0.33 ± 0.01g), were distributed in twenty tanks (130L each). Each tank with five juveniles was considered an experimental unit, with water recirculation. Performance, heterogeneous growth, morphometric and physiological parameters, and economic viability of the rations according to the CP levels were evaluated. For the regression analysis, a linear increase in performance, heterogeneous growth and morphometric and physiological parameters with increased of the protein in rations were observed. When compared by the Tukey test (P>0.05), the best results were obtained with 36% CP. There was lower fish growth heterogeneity as the levels of CP in the diet increased. Thus, taking into consideration the economic viability it is recommended to use feed containing 36% of crude protein to curimatã-pacu juveniles.

Crescimento heterogêneo de tilápia do Nilo alimentados com resíduo de biscoito na dieta

O objetivo deste trabalho foi avaliar o efeito de quatro niveis da adicao de residuo de biscoito (0, 7.0, 14.0 e 21.0%) na dieta de juvenis de tilapia do Nilo sobre o crescimento heterogeneo, com peso inicial medio de 3,0±0,5g em um delineamento experimental inteiramente casualisado (DIC) com quatro tratamentos e cinco repeticoes, foram utilizados 100 animais peso medio inicial de 3,0±0,5g distribuidos em 20 aquarios experimentais de 130L cada onde permaneceram por 60 dias, foram alimentados tres vezes ao dia ate a aparente saciedade. Os peixes alimentados com 14% de residuo de biscoito apresentaram melhor crescimento homogeneo.

Biodigestão anaeróbia do bagaço da cana-de-açúcar pré-tratado e utilizando excretas de frango como inóculo

The sugar cane and poultry industry are generators of a large amount of byproducts that can have their added value enhanced when used as an energy source. Thus, the objective of this study was to investigate the effect on anaerobic biodigestion of sugarcane bagasse in natura and pretreated with sodium hydroxide, using chicken excreta as inoculum. To do this, 600mL experimental biodigesters were used, with two treatments: 1 sugarcane bagasse inoculated with bird excreta and 2 sugarcane bagasse inoculated with bird excreta and added 4% sodium hydroxide solution (NaOH). The chemical composition of sugarcane bagasse and bird excreta were analyzed, as well as how the reactive sludge (substrate) were evaluated, before and after the period of 54 days. The variables of pH, DQO, total, volatile and fixed solids and also the production of methane gas (CH4) were analyzed. The results show that the treatment with 4% sodium hydroxide

Restrição alimentar no desempenho de machos do peixe beta (Betta splendens)

The aim of this study was to evaluate the effects of alimentary restriction on Betta splendens performance. For the experiment, 24 males were used, with initial average weight of 0.55 ±0.06 grams, distributed in 24 experimental aquaria with 1.5 liters of water without aeration in a completely randomized design, with four treatments and six repetitions. The treatments were: T1 – daily fed animals (control), T2 - fed for six days and one day of restriction (6A/1R), T3 - fed for five days and two days of restriction (5A/2R) and T4 - fed for four days with three days of restriction (4A/3R). The fishes were fed twice a day at 08:00am and 4:00pm. The variables studied were: final weight (FW), weight gain (WG), alimentary conversion (FC), average feed consumption (CMR), total length (CTOTAL), standard length (CPADRAO) profile index (IPERFIL), condition factor (CF) and height. The results were submitted to variance analysis (ANOVA), and the means were compared by Tukey´s test at 5% of probability. No significant differences were observed for the following variables: water quality, survival, alimentary conversion and profile index. The best growth performance was observed when the feeding management of 6A/1R was applied.

Desempenho de Betta splendens associados a diferentes frequências alimentares

O objetivo deste estudo foi determinar a melhor frequencia de arracoamento necessaria sobre o desempenho de Betta splendens . Foram utilizados 28 alevinos de Beta, machos, acondicionados individualmente em aquarios experimentais, com capacidade efetiva de 1,5L de agua e submetidos a quatro tratamentos, frequencias alimentares (1 a cada 2 dias, 1 vez ao dia, 2 e 4 vezes ao dia) e cinco repeticoes, organizados num delineamento inteiramente ao acaso, durante 45 dias. Foram avaliados os parâmetros de desempenho, a qualidade da agua e o comportamento social dos animais submetidos as diferentes frequencias de alimentacao. Os dados foram submetidos a ANOVA e ao teste de Tukey (P<0,05). Com os resultados obtidos pode-se observar que os animais foram alimentados quatro vezes ao dia obtiveram um melhor peso final, consumo de racao e conversao alimentar, porem nao diferiu estatisticamente do tratamento em que os animais foram alimentados duas vezes ao dia. O tratamento alimentado uma vez ao dia nao apresentou diferencas significativas quando comparado ao tratamento em que os animais foram alimentados duas vezes ao dia. O tratamento em que os animais foram alimentados uma vez por dia, em dias alternados, apresentou os piores resultados de desempenho. Recomenda-se assim, a oferta de racao balanceada, na forma “ ad libitum ”, duas vezes ao dia, para machos de Betta splendens .