Caracterização de efluentes de viveiros de engorda de rã-touro (lithobates catesbeianus, Shaw, 1802)

Aim: Current analysis characterizes the effluent from bullfrog-rearing ponds during the grow-out phase; Methods: Temperature, pH, dissolved oxygen, electric conductivity, turbidity, total phosphorus, N-NH3, N-NO3, BOD5 and COD and the number of thermotolerant coliforms (Escherichia coli) of the inlet and outlet water of the ponds were analyzed twice a week. Assay consisted of a completely randomized experimental design with two treatments (inlet and outlet water) and six repetitions in a split-plot, coupled to collection over time as subplot; Results: All variables were significantly different (p < 0.05) between treatments and over time (p < 0.05). Average rates of temperature, pH and dissolved oxygen levels of the supply water were higher when compared to those of the effluent. The other variables such as conductivity, turbidity, total phosphorus, ammonia, nitrate, biological oxygen demand, chemical oxygen demand and E. coli were higher in the effluent when compared to rates in the supply water; Conclusions: The management during grow-out phase caused the deterioration of the water quality, with increasing levels of dissolved nutrients and the number of thermotolerant coliform. Ammonia and phosphorus levels in the effluent, caused by waste food, skin and feces, accelerate the eutrophication process of the receiving water body. Further studies on effluent treatment are required.

Crescimento, comportamento ingestivo e desempenho reprodutivo de novilhas mestiças holandês x zebu, em pastejo, submetidas à suplementação protéica durante a época das águas

The objective of this study was to evaluate the effect of supplemental protein during the rainy season on body growth, ingestive behavior and reproductive performance of crossbred Gir x Holstein dairy heifers, with mean age of 21 ± 4.1 months and average initial body weight of 296.7 ± 57.3 kg, distributed in a completely randomized design with four treatments and six replicates per treatment. Heifers remained on Brachiaria brizantha cv. Marandu pasture, managed according to a rotational grazing system and, as treatment, it was supplemented with protein concentrate (34%, 43%, 56% and 66% BW) and level of supply of 0.30% body weight (BW). The animals were weighed and the mean weight of the lot was used for the calculation of adjustment of the amount of concentrate offered. Heifers that reached 330.0 kg of live weight were artificially inseminated and, 45 days after insemination, pregnancy diagnosis was performed for the calculation of pregnancy rate and age at conception. No significant difference of protein levels was observed on grazing, eating behavior, productive performance and age at conception of dairy heifers on pasture. The average daily weight gain of BW and age at conception were, on average, 0.907 kg/animal and 24.03 months, respectively.

Impacts of enemy-mediated effects and the additivity of interactions in an insect trophic system

In this study, we used data from both experiments and mathematical simulations to analyze the consequences of the interacting effects of intraguild predation (IGP), cannibalism and parasitism occurring in isolation and simultaneously in trophic interactions involving two blowfly species under shared parasitism. We conducted experiments to determine the short-term response of two blowfly species to these interactions with respect to their persistence. A mathematical model was employed to extend the results obtained from these experiments to the long-term consequences of these interactions for the persistence of the blowfly species. Our experimental results revealed that IGP attenuated the strength of the effects of cannibalism and parasitism between blowfly host species, increasing the probability of persistence of both populations. The simulations obtained from the mathematical model indicated that IGP is a key interaction for the long-term dynamics of this system. The presence of different species interacting in a tri-trophic system relaxed the severity of the effects of a particular interaction between two species, changing species abundances and promoting persistence through time. This pattern was related to indirect interactions with a third species, the parasitoid species included in this study. © 2012 The Society of Population Ecology and Springer Japan.

Improvement of Matrinxã, Brycon amazonicus, Larviculture by Exposing Eggs to Triiodothyronine

This work evaluated the effect of triiodothyronine (T3) on larviculture of matrinxã, Brycon amazonicus. Oocytes of three females were pooled, fertilized with pooled semen of two males and separated in four batches that were immersed in triiodothyronine solutions as follows: M1 (control - water); M2 (0.01mg/L T3); M3 (0.05mg/L T3); and M4 (0.1mg/L T3). Triiodothyronine did not affect fertilization rate and number of hatched larvae. Weight of hatched larvae was significantly higher in treatments M3 and M4, as well as among larvae sampled at Day 12 in all treatments. After 12d of rearing, biomass gain was higher in the hormone treatments (M1 688±569mg; M2 2436±562mg; M3 3572±569mg; and M4 4129±770mg). In general, coefficients of variation of weight (CVw) and length (CVl) did not differ among treatments and cannibalism was registered between 36 and 72hours post-hatching (h.p.h.) without differences among treatments. Larval survival increased in the hormone treatments (M1 26.5%; M2 37.6%; M3 40.6%; and M4 40.8%). The results indicate that the immersion of matrinxã eggs in triiodothyronine can promote beneficial effects to its larviculture and indicate promising perspectives for culture of this tropical species. © by the World Aquaculture Society 2013.

A new species of megastigmus (hymenoptera: Torymidae: Megastigminae) from Brazil

In this paper a new parasitoid Megastigmus Dalman, 1820 (Hymenoptera: Chalcidoidea: Torymidae: Megastigminae) species was described in the subgenus Torymus, associated with the gall-forming Leptocybe invasa Fisher & La Salle (Hymenoptera: Eulophidae) in eucalypt plantations in Brazil.

Potencial reprodutivo de Chrysoperla externa (Neuroptera: Chrysopidae): Efeito da proporção sexual e período de acasalamento

In this study the effects of the time of male permanence with females and different sex ratios on the reproductive capacity of Chrysoperla externa F 3 adults was evaluated. The insects were kept at 25 ± 2 °C, 70 ± 10% RH, under a 12 h photoperiod. The first experiment consisted of mating females with males that were subsequently removed after 5, 10, 15, 20, 25, 30, 35 and 40 days; the control group consisted of males remaining with the females during the entire experimental period. The second experiment consisted of mating: one male with one female (1:1); one male with two females (1:2); one male with three females (1:3); one male with four females (1:4); and one male with five females (1:5), and then evaluating their pre-ovipositioning periods, daily and total ovipositioning, egg viability percentages, and efficiency indices (which considered total ovipositioning, mean egg viability, and the ovipositioning period). It was found that alternating the sexual proportions from one male with one female to one male with three females did not alter the reproductive performance of these insects, and that there was no need to replace the males after five days as they were able to provide sufficient numbers of spermatozoa during this period to maintain consistent reproductive rates.

Mean surface temperature prediction models for broiler chickens-a study of sensible heat flow

Body surface temperature can be used to evaluate thermal equilibrium in animals. The bodies of broiler chickens, like those of all birds, are partially covered by feathers. Thus, the heat flow at the boundary layer between broilers' bodies and the environment differs between feathered and featherless areas. The aim of this investigation was to use linear regression models incorporating environmental parameters and age to predict the surface temperatures of the feathered and featherless areas of broiler chickens. The trial was conducted in a climate chamber, and 576 broilers were distributed in two groups. In the first trial, 288 broilers were monitored after exposure to comfortable or stressful conditions during a 6-week rearing period. Another 288 broilers were measured under the same conditions to test the predictive power of the models. Sensible heat flow was calculated, and for the regions covered by feathers, sensible heat flow was predicted based on the estimated surface temperatures. The surface temperatures of the feathered and featherless areas can be predicted based on air, black globe or operative temperatures. According to the sensible heat flow model, the broilers' ability to maintain thermal equilibrium by convection and radiation decreased during the rearing period. Sensible heat flow estimated based on estimated surface temperatures can be used to predict animal responses to comfortable and stressful conditions. © 2013 ISB.

Telenomus remus Nixon Egg Parasitization of Three Species of Spodoptera Under Different Temperatures

Telenomus remus Nixon is a promising biocontrol agent as an egg parasitoid of Spodoptera spp., but the lack of information on the host-parasitoid interactions in this system precludes its applied use in agriculture. Therefore, we studied the parasitism capacity of T. remus on eggs of Spodoptera cosmioides (Walker), Spodoptera eridania (Cramer), and Spodoptera frugiperda (Smith) in a range of temperatures (19, 22, 25, 28, 31, and 34 ± 1°C) under controlled conditions (70 ± 10% RH and 12 h photophase). Egg masses of Spodoptera spp. were offered to a single-mated T. remus female on a daily basis. More than 80% lifetime parasitism on eggs of S. cosmioides, S. frugiperda, and S. eridania was reached from 1 to 5, 1 to 7, and 1 to 9 days, respectively, at temperatures from 19 to 34°C. More than 80% parasitization was obtained at extreme temperatures for all hosts studied. Lifetime parasitization of S. frugiperda, S. cosmioides, and S. eridania was affected by temperature, with the lowest values for S. frugiperda (34°C) and S. cosmioides (19 and 34°C). Parasitization of S. eridania eggs was reduced around 18% at 28 and 31°C, but dropped more severely at 34°C. Parasitoid longevity was reduced as temperature increased. Thus, our data indicated that T. remus might be suitable as a biocontrol agent against S. eridania, S. cosmioides, and S. frugiperda in geographical areas that fit the temperature range studied here, even though T. remus parasitism was reduced at 34°C. © 2013 Sociedade Entomológica do Brasil.

Desenvolvimento corporal de novilhas leiteiras suplementadas com minerais inorgânicos e orgânicos em pastejo na época das águas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of Low-Temperature Storage on Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae)

We evaluated the effects of constant low-temperature storage on Diaeretiella rapae (McIntosh) (Braconidae, Aphidiinae). Diaeretiella rapae mummies were stored at 5 ± 1°C for 0-36 days. The percentage of D. rapae emergence varied (100-83%) after 0-32 days of storage. After 32 days, emergence reduced to 55%. According to our Probit analysis, 50% mortality (LT50) of the population of D. rapae was reached after 40 days of storage at 5°C. Storage for up to 32 days did not negatively affect emergence and survival. Cold exposure of D. rapae for 36 days did not influence morphological malformations, sex ratio, and emergence of the F1 generation. After 4-36 days of storage, D. rapae showed a gradual decrease in emergence, longevity, reproductive capacity, and F1 sex ratio. Diaeretiella rapae can be stored for up to 24 days at 5°C, at which time the percentage of parasitism and the F1 sex ratio remain above 38% and at 0.50, respectively. © 2013 Sociedade Entomológica do Brasil.

Comportamento de poedeiras criadas a diferentes densidades e tamanhos de grupo em ambiente enriquecido

The objective of this work was to determine the behavioral differences among laying hens reared at different densities and group sizes, in an enriched environment. Isa Brownlaying hens with ages from 30 to 32-week-old, in small-sized and deformed pens, were used. Hens were raised during 28 days in bays with shavings bedding, perch and nest. Two group sizes were evaluated (6 and 12 fowls) and at two rearing densities (774 and 1,440 cm2 by fowl) in a factorial arrangement with three replicates. In fifteen-minute video footages, it was recorded the frequency and the expression period for the following behavior were recorded: feather scratching, sand bath, wing beating, drinking water, pecking, head scratching, earth scratching, eating, perching, leg stretching, pursuing, sitting, and nest visiting. The treatments and the interaction between them had significant effects. The six-hen group increased the frequency of behavior types that indicate fowl frustration, regardless of density. The group size is the most important factor for hen well-being.

Estudos morfológicos e histoquímicos do tubo digestivo de Hemisorubim platyrhynchos (Valenciennes, 1840)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Substituição precoce do alimento vivo pelo alimento inerte na larvicultura de acará bandeira (Pterophyllum scalare)

Pós-graduação em Aquicultura - FCAV

Perfil de cortisol, glicemia e de parâmetros sanguineos de girinos de rã-touro, Rana catesbeiana, em diferentes densidades e após exposição aérea

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

Efeito da intensificação na larvicultura do camarão-da-malásia Macrobrachium rosenbergii

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)