Produção da tilápia vermelha da Flórida em tanques-rede

A produção de peixes em tanques-rede no Brasil tem aumentado nas últimas décadas. O baixo investimento inicial e o potencial hídrico representado pela enorme quantidade de água represada em nosso País têm atraído o interesse de empresários para essa atividade. O objetivo desse trabalho foi gerar informações sobre o efeito da densidade de estocagem no crescimento e produtividade da tilápia vermelha da Flórida criadas em tanques-rede. Foram instalados doze tanques-rede de 5 m3, numa represa de 1 ha, e estocados com 25, 50, 75 e 100 tilápias vermelhas da Flórida revertidas por m3. Os peixes foram alimentados com rações extrusadas comerciais contendo 32 e 28% PB por 253 dias. As temperaturas máxima, mínima e média da água foram 32,2, 16,0 e 23,9 C, respectivamente. Também foram monitorados a condutividade (58 mS/cm2), alcalinidade total (28 mg/L), amônia não ionizada (0,26 mg/L), nitrito (0,02 mg/L), oxigênio dissolvido (4,1 mg/L) e transparência da água (37 cm). Foram determinados o peso médio final (279,54g), comprimento padrão médio final (18,72cm), fator de condição (4,12), conversão alimentar aparente (3,15), taxa de sobrevivência (96,9%), ganho de peso diário (0,92g), taxa de crescimento específico (0,70%) e coeficientes de variação do peso (0,357%), do comprimento padrão (0,136%) e do fator de condição (0,136%). Não foram observadas diferenças significativas (P>0,05) entre as densidades de estocagem testadas nesses parâmetros. A densidade de estocagem de 100 peixes/m3 proporcionou a maior biomassa por m3 (P<0,001).

Redução do amido dietético, utilizando óleo de soja, em dietas para coelhos em crescimento

Este experimento foi conduzido para avaliar os efeitos da redução do amido dietético, utilizando óleo de soja, em dietas para coelhos Nova Zelândia Branco em crescimento sobre o desempenho e rendimento de carcaça dos animais. Os coelhos foram desmamados aos 30 dias e abatidos aos 60 dias de idade. O delineamento experimental foi em blocos ao acaso com quatro tratamentos (2,2, 3,3, 4,4 e 5,5% de adição de óleo de soja às dietas) e cinco repetições com 15 animais por tratamento. Foram avaliados os ganhos de peso diário, a ingestão de alimentos diária, a conversão alimentar, a mortalidade e o rendimento de carcaça. Não houve efeito (P>0,05) dos tratamentos sobre os parâmetros avaliados. Concluiu-se que, nas condições realizadas neste trabalho, a adição de óleo de soja em dietas para coelhos em crescimento até o nível de 5,5% não afetou o desempenho produtivo.

Drying kinetics of tomato by using electric resistance and heat pump dryers

Drying kinetics of tomato was studied by using heat pump dryer (HPD) and electric resistance dryers with parallel and crossed airflow. The performance of both systems was evaluated and compared and the influence of temperature, air velocity, and tomato type on the drying kinetics was analyzed. The use of HPD showed to be adequate in the drying process of tomatoes, mainly in relation to the conversion rate of electric energy into thermal energy. The heat pump effective coefficient of performance (COPHT,EF) was between 2.56 and 2.68, with an energy economy of about 40% when compared to the drying system with electric resistance. The Page model could be used to predict drying time of tomato and statistical analysis showed that the model parameters were mainly affected by drying temperature.

Use of Yucca schidigera extract in broiler diets and its effects on performance results obtained with different coccidiosis control methods

A trial was conducted to assess the effects of the dietary supplement Yucca schidigera extract on the performance of broilers subjected to different coccidiosis control methods. Six hundred male broiler chicks were randomly allocated to 1 of 5 treatments with 4 replicates each. The treatments were as follows: T1, vaccinated against coccidiosis; T2, nonvaccinated, a dietary coccidiostat; T3, vaccinated against coccidiosis, diet supplemented with Y. schidigera extract (0.01%); T4, coccidiostat plus Y. schidigera extract added to feed (0.01%); and T5, nonvaccinated, nonsupplemented control. The parameters analyzed were bird performance and morphology of the intestinal mucosal surface. The intestinal villi were higher at 6 d of age in broilers treated with coccidiostats or vaccinated against coccidiosis and supplemented with Y. schidigera extract compared with groups receiving the vaccine only or no treatment. Addition of the Y. schidigera extract to the diet of vaccinated birds improved average daily gain and feed conversion rate at 42 d of age compared with the other treatments, suggesting there might be a beneficial, synergistic effect between the coccidiosis vaccine and the Y. schidigera extract.

Dietary digestible lysine requirement and essential amino acid to lysine ratio for pacu Piaractus mesopotamicus

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Production strategies for short term grow-out of the Amazon River prawn Macrobrachium amazonicum (Heller 1862) in ponds

The aim of this study was to evaluate the effect of stocking ponds using graded and ungraded juveniles and performing drained and combined harvesting on the production of M. amazonicum. A randomized completed-blocks design with 4 treatments (farming strategies) and 3 replicates was used. Treatments were: Upper size-graded juveniles, Lower size-graded juveniles, Ungraded juveniles, all with total drained harvesting, and Combined Harvesting (ungraded juveniles). Twelve earthen ponds were stocked at 40 juveniles.m -2, according to the treatment. After 3.5 months prawns were completely harvested. Lower size-graded prawns showed smaller average weight (3.37 ± 0.25 g) than upper size-graded (4.03 ± 0.40 g) and ungraded ones (3.80 ± 0.16 g). Survival percentage varied from 68 ± 9 to 76 ± 10, productivity was slightly higher than 1,000 kg.ha -1 and apparent feed conversion rate varied from 3.0 ± 0.7 to 3.7 ± 1.3. These parameters did not differ among the farming strategies. The best strategy for short term grow-out M. amazonicum in earthen ponds is stocking ungraded juveniles and performing total harvesting by draining ponds at the end of rearing cycle. Grading juveniles before stocking and selective-harvesting managements are not advantageous because they increase costs and do not improve any production parameter.

Greenhouse gas mitigation potential from green harvested sugarcane scenarios in São Paulo State, Brazil

Brazil is a major sugarcane producer and São Paulo State cultivates 5.5 million hectares, close to 50% of Brazil's sugarcane area. The rapid increase in production has brought into question the sustainability of biofuels, especially considering the greenhouse gas (GHG) emissions associated to the agricultural sector. Despite the significant progress towards the green harvest practices, 1.67 million hectares were still burned in São Paulo State during the 2011 harvest season. Here an emissions inventory for the life cycle of sugarcane agricultural production is estimated using IPCC methodologies, according to the agriculture survey data and remote sensing database. Our hypothesis is that 1.67 million hectares shall be converted from burned to green harvest scenarios up to years 2021 (rate 1), 2014 (rate 2) or 2029 (rate 3). Those conversions would represent a significant GHG mitigation, ranging from 50.5 to 70.9 megatons of carbon dioxide equivalent (Mt CO2eq) up to 2050, depending on the conversion rate and the green harvest systems adopted: conventional (scenario S1) or conservationist management (scenario S2). We show that a green harvest scenario where crop rotation and reduced soil tillage are practiced has a higher mitigation potential (70.9 Mt CO2eq), which is already practiced in some of the sugarcane areas. Here we support the decision to not just stop burning prior to harvest, but also to consider other better practices in sugarcane areas to have a more sustainable sugarcane based ethanol production in the most dense cultivated sugarcane region in Brazil. © 2013 Elsevier Ltd. All rights reserved.

Stocking density of Nile tilapia in cages placed in a hydroelectric reservoir

The Brazilian government has been encouraging fish farming in cages in federal water bodies, including hydroelectric reservoirs. Despite the government support, it is a new activity and the production model still needs some adjustment to reduce the production costs and achieve sustainability. The aims of this study were to determine the appropriate stocking density of Nile tilapia in cages in a hydroelectric reservoir and to evaluate to what extent fish size selection could improve their uniformity. Twelve cages (6m3) were placed at the Fish Farmers' Cooperative of Santa Fé do Sul and Region, Ilha Solteira reservoir, São Paulo, Brazil (20°12'10″S, 50°58'31.15″W). In stage I (initial fish weight, 78g), four stocking densities were tested: D1-800, D2-2000, D3-2500 and D4-3000 fish/cage, with three replicates. At the end of this stage (average fish weight, 255g), the fish were selected into three sizes, except for D1. In stage II, four stocking densities were tested, designed to obtain the following final production: D1-100kg/m3 (800 non-selected fish/cage), D2-80kg/m3 (600 fish/cage), D3-100kg/m3 (800 fish/cage) and D4-120kg/m3 (900 fish/cage). The trial ended when the fish weighed 800g. By reducing the initial stocking density from 2500 to 800 tilapia juveniles per cage, there was no need for selection. The growth performance was higher, the feed conversion rate was better and the time taken to reach harvesting was shorter. Consequently, the production cost reduced and the operating profit increased. Using the lowest initial stocking density, the risk of disease outbreak was also lower, and there was no need to use drugs for disease control since the mortality rate and occurrences of disease and deformity decreased and the dissolved oxygen level inside the cages was higher. © 2013 Elsevier B.V.

Sistemas de criação para o Acará-bandeira Pterophyllum scalare

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da densidade de estocagem na sobrevivência e crescimento do pampo (Trachinotus carolinus) em tanques-rede marinhos

Pós-graduação em Aquicultura - FCAV

Suplementação dietária de cobre no desempenho produtivo da tilápia-do-Nilo e resposta hemática sob estresse térmico

Pós-graduação em Zootecnia - FMVZ

Somatotropina bovina recombinante (rbST) e grupo racial sobre o desempenho, características de carcaça e qualidade da carne de caprinos em crescimento

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Achados anatomopatológicos em perdizes (Rhynchotus rufescens) criadas em cativeiro

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Modulação química do crescimento na tilápia-do-Nilo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Criação de Tilápia-do-Nilo, Oreochromis niloticus, em Tanques-rede, na Usina Hidrelétrica de Chavantes, Rio Paranapanema, SP/PR

Pós-graduação em Aquicultura - FCAV