Biodegradation and Detoxification Efficiency of Azo-Dye Reactive Orange 16 by <Emphasis Type="Italic">Pichia kudriavzevii</Emphasis> CR-Y103

In consideration of the hazards associated with the presence of the textile azo-dye and their biotransformation products in the environment, the goal of this work was to study bioremediation process by the yeast strain Pichia kudriavzevii CR-Y103 related to the ability to degrade and detoxify the sulfonated Reactive Orange 16 azo-dye. In experimental conditions, the optimal inoculum/dye concentration ratio required for complete decolorization (100%) of culture medium and biomass within 24 h has been 1 g L^?1 yeast cell (dry weight)/50 mg L^?1 Reactive Orange 16. In the presence of 400 mg L^?1 of Reactive Orange 16 (RO16), 95% of the dye was removed after 72 h of incubation. Also, the yeast strain could decolorize other eight textile dyes (56.48–99.98% decolorization within 24 h). NADH-DCIP reductase and azo reductase activities were significantly increased (ca. 5.4 times and ca. 37 times, respectively) during the decolorization process. UV-VIS spectra, high-performance liquid chromatography (HPLC), and Fourier transform infrared spectroscopy (FTIR) analysis confirmed the presence of new biotransformation products in extracted metabolites, highlighting the partial biodegradation of the dye by the new yeast isolate. The phytotoxicity evaluation strongly supported the decreased toxicity of biodegraded products as minor inhibition on germination (%), root and shoots elongation of T. pratense L. and T. aestivum L. seedlings. Increasing of mitotic index value and decreasing the frequency of chromosomal aberrations in tested plant meristem cells treated with biodegraded products, compared with RO16 treatment (500 ppm), confirmed their slightly toxic nature. A cell viability assay also confirmed the reduced toxicity of biodegraded products on healthy monkey kidney cells (Vero cells).     

Lethal and sublethal responses of <Emphasis Type="Italic">Sitophilus zeamais</Emphasis> populations to essential oils

The present study aimed to assess the lethal and sublethal responses of five populations of S. zeamais to the essential oils of Ocimum basilicum and Piper hispidinervum, through toxicity, locomotor behavior (flight and walking activities) and physiological (respiration rate and body mass) evaluations. The populations of S. zeamais were obtained from Machado—MG, Paracatu—MG, Piracicaba—SP, Recife—PE and Tunápolis—SC. To estimate the LC₅₀ of each oil for each population, fumigation tests were performed. The population from Recife exhibited the lowest instantaneous rate of increase (ri) as well the lowest consumption of grain mass. However, Piracicaba was considered the susceptibility pattern, presenting the lowest LC₅₀ for both essential oils, no statistical difference was observed among populations or treatments in the flight activity bioassays. The essential oils effect on walking activity and respiration rates varied among populations. The population from Recife presented the highest walked distance and walk speed, with the lowest resting time and number of stops, as well as the lowest respiration rate and body mass. The present study highlights the importance of the study on population responses, as the five populations of S. zeamais exhibited different patterns of toxic and behavioral effects when subjected to the essential oils of P. hispidinervum and O. basilicum.     

Evaluating the potential for farmer and plant breeder collaboration: A case study of farmer maize selection in Oaxaca, Mexico

Formal plant breeders could contribute much to collaboration with farmers for improving crop varieties for local use. To do so outside researchers must have some understanding of local selection practices and their impact on crop populations in terms of the genetic theory underlying plant breeding. In this research we integrated methods from social and biological sciences to better understand selection and its consequences from farmers' perspectives but based on the concepts used by plant breeders. Among the households we worked with, farmers' selection practices were not always effective yet they understood the reasons for this and had no expectations for response to selection in some traits given the methods available to them. Farmers' statements, practices and genetic perceptions regarding selection and the genetic response of their maize populations to their selection indicate selection objectives different than may be typically assumed, suggesting a role for plant breeder collaboration with farmers. This revised version was published online in July 2006 with corrections to the Cover Date.     

Effect of diets on carotenoid content,body coloration,biochemical composition and spermatophore quality in the “red cherry” shrimp Neocaridina davidi (Caridea,Atyidae)

In aquarium industry trade markets, Neocaridina davidi, the “red cherry” shrimp, is one of the most attractive ornamental shrimps due to the striking reddish coloration of females. Five commercial diets formulated for ornamental species were evaluated over a 90‐day period in N. davidi males and females, based on survival, biochemical composition, body weight, carotenoid content and body coloration. Furthermore, histological and histochemical analyses of the male reproductive system were performed to evaluate the spermatophore quality. In all treatments, survival was >80%, and protein content was similar in both female and male shrimps. Lipid content was higher in females and males fed on a diet having the highest lipid level. Carotenoid content was higher and body coloration was brighter in females and males fed on a diet containing the highest carotenoid level. Histological and histochemical analyses of the spermatophore structure and composition showed no differences among diets, suggesting that the five commercial diets are adequate for satisfactory growth and spermatophore quality of N. davidi. The diverse sources and quantities of carotenoids in the highest carotenoid level diet render it more suitable for colour enhancement of this species.     

Effect of experimental arginine supplementation on the growth,immunity and resistance of tilapia fingerlings to Streptococcus agalactiae

Streptococcosis causes serious economic losses to fish farms every year. A four‐week feeding trial was carried out to evaluate arginine (ARG) supplementation in the diet of Nile tilapia (Oreochromis niloticus) fingerlings challenged by Streptococcus agalactiae. Fish were fed with experimental diets containing five levels of supplementation with 1.39%, 1.76%, 1.97%, 2.18% or 2.39% analysed level of ARG. Each diet was randomly distributed in 30 tanks containing 20 fish/tank. After 30 days, no differences were observed in performance parameters, weight gain, daily weight gain, specific growth rate, feed intake or food conversion. After the performance assay, fingerlings were infected with 1.95 × 10⁸ CFU/fish of Streptococcus agalactiae. Mortality was verified daily, and the respiratory burst of leucocytes and nitric oxide production were measured at 0 hr, 24 hr, 7 days and 15 days after infection. The survival rate of the fish is compared using the Kaplan–Meier method, with values of 4.29%, 14.8%, 10.8%, 17.2% and 33.3% for the 1.39, 1.76, 1.97, 2.18 and 2.39 treatments respectively. A reduction in the mortality rate and a boost in the immune responses was observed in all the supplementations of ARG in the diet; however, the best survival rates were obtained in the treatments with 2.39% ARG as well as the most efficient immune responses.     

Spontaneous neoplasia in captive syngnathid species: A retrospective case series (2003–2014) and literature review

Syngnathidae (seahorses, pipefish and seadragons) are charismatic species commonly kept in commercial aquaria, but published literature on syngnathid diseases is limited and immunohistochemical techniques not routinely employed. A retrospective review of 2,541 syngnathid submissions received between March 2003 and October 2016 identified 18 neoplasms including germ cell tumours, exocrine pancreatic and intestinal carcinomas, chromatophoromas, and single cases of lymphoma, thyroid and renal carcinoma, swim bladder and pituitary adenoma. Big-bellied seahorses accounted for 19% of submissions, but 50% of neoplasms were diagnosed in this species. This study includes the first reported cases of germ cell tumours, chromatophoroma, thyroid carcinoma and pituitary adenoma in Syngnathidae and the first reports of neoplasia in pipefish species. Out of nine commercial antibodies trialled for immunohistochemical characterization of neoplastic tissue, only pan-cytokeratin proved cross-reactive. Electron microscopy was performed in four cases. Tumours should be considered as differential diagnosis in cases with buoyancy issues, debilitated or emaciated animals, and may predispose to secondary infections. This study highlights the value of histopathological disease surveillance for commercial aquarium settings.     

An integrated approach for cetacean knowledge and conservation in the central Mediterranean Sea using research and social media data sources

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Mesquite bean (Prosopis juliflora) meal in diets of Nile tilapia (Oreochromis niloticus): Nutritional value,growth, physiological responses and health

Two experiments were conducted to assess the nutritional value and potential use of mesquite bean (Prosopis juliflora) meal (MBM) to substitute corn in extruded diets for Nile tilapia (Oreochromis niloticus). Digestible energy and the content of protein, soluble carbohydrates and amino acids were measured for 160 Nile tilapia juveniles (average weight 25.58 ± 5.52 g), allocated to eight treatment groups (four fed the experimental diet, and four fed a reference diet). To determine the inclusion potential of MBM, 384 fish (average weight 21.85 ± 1.01 g) were used and allocated to 24 tanks (1,000 L capacity). The experimental design was completely randomized with six levels of substitution (0%, 20%, 40%, 60%, 80% and 100%), and four repetitions. After the feeding experiment, tissue samples (blood, liver, muscle and intestine) were used to analyse metabolic and haematological variables. MBM produced apparent digestibility coefficients (ADC) similar to those of traditional diet ingredients: 81.85% dry matter (DM), 83.02% crude energy, 88.57% crude protein, 82.88% lysine and 82.57% methionine. Differences were observed in the digestibility of soluble carbohydrates (p < 0.05), with MBM having higher levels of starch (72.19%) and sucrose (88.99%). A 20% substitution with MBM produced a decrease in zootechnical performance (p < 0.05). Enzymatic activity of amylase and sucrose seemed to be induced in response to the proportion of their respective substrate in the diets. We observed a reduction in the efficiency of dietary protein utilization, with reduced levels of plasma amino acids (p < 0.05), owing to the increase in the enzymatic activity of muscular alanine and aspartate transaminases (ALT and AST) and the deaminase glutamate dehydrogenase in the hepatic and muscular tissues. Haematological variables did not indicate any adverse effects of MBM on the health status or survival of the fish (100%). Therefore, we conclude that MBM may be a viable alternative to corn meal in the diet, enabling substitution of up to 20%.