Effect of ascorbic acid supplementation on zootechnical performance,haematological parameters and sperm quality of lebranche mullet Mugil liza

The feed provided to breeding fish is one of the main factors influencing the quality of fish gametes. This study was carried out to evaluate the influence of ascorbic acid on growth, haematological parameters and sperm quality of Lebranche mullet males (Mugil liza). Six diets with different levels of ascorbic acid (0; 53; 107; 216; 482 and 708 mg/kg) were tested in triplicate for 75 days. During spermiation (first gonadal maturation), 144 individuals (205.7 ± 11.5 g and 25.7 ± 0.4 cm) were randomly distributed in 18 experimental tanks. Growth parameters were evaluated at the beginning and end of the experiment. Fish blood was collected to analyse glucose, total protein and erythrocyte count (EC) (n = 9). Fish (n = 12) from each treatment were euthanized to determine hepatosomatic index (HSI) and gonadosomatic index (GSI). Semen was collected to evaluate spermatic density, cell membrane integrity and sperm motility. No difference (p > .05) was found on growth parameters, GSI, HSI and total protein. However, EC was lower in fish fed without ascorbic acid (the control group). Ascorbic acid supplementation provided positive effects on sperm characteristics. Fish from treatments with 53 and 107 mg/kg presented the best results for motility time (133.30 ± 4.25 and 135.00 ± 2.77 respectively). Treatments with 107, 216 and 708 mg/kg provided the best results for motility rate (92.0 ± 2.9%, 93.0 ± 5.8% and 93.0 ± 5.8% respectively). Supplementation with 107 and 216 mg/kg provided the best results for plasma membrane integrity (70.12 ± 9.10% and 76.3 ± 3.1% respectively). Lower spermatic density was observed in fish without ascorbic acid supplementation, although no difference was found in sperm density among the treatments with ascorbic acid (p < .05). Considering these results, supplementation of dietary ascorbic acid between 107 and 216 mg/kg optimizes the spermatic quality in males of lebranche mullet.     

Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study

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Physicochemical Properties of Oat Varieties and Their Potential for Breadmaking

The breadmaking potential of six oat varieties was compared with and related to their physicochemical properties. The most significant differences in the bread characteristics were found in the crumb structure. The varieties Buggy, Energie, and Zorro resulted in good bread quality with an even gas‐cell distribution characterized by a high number of relatively small pores. In contrast, Typhon, Ivory, and Nord 08/311 each had a large hole in the center of the crumb and accordingly poor quality. Breads differed little in specific volume, bake loss, and density. Rheological analysis revealed positive effects of low batter resistance to deformation on oat bread quality. On the basis of the physicochemical characterization, protein and fat contents were identified as key factors responsible for differences observed in bread quality, provided that starch damage and water‐hydration capacity were low. Additionally, high setback and final viscosity, as determined by Rapid Visco Analyser (RVA) analysis, positively affected oat bread quality. High α‐amylase activity was found to influence negatively the breadmaking performance of oats. Overall, protein, fat, dietary fiber content, starch pasting properties, and α‐amylase activity were responsible for the breadmaking properties of oat varieties.     

Tub gurnard Chelidonichthys lucerna L.: a new fish species suitable for farming? First answers evaluating the growth of juveniles reared at different stocking densities,welfare and fillet quality

A trial was conducted to evaluate the growth performance and survival of Chelidonichthys lucerna. A total of 13 352 180‐days old juveniles (5.5 ± 2 g; 5 ± 1 cm) were reared at two different densities (A‐EXP = 68 fish m^?3; B‐FFA = 15 fish m^?3) in eight tanks (four tanks per group) for 360 days. The welfare status and meat quality of fish were evaluated for the A‐EXP and B‐FFA groups in comparison with wild‐caught fishery gurnard (C‐WID). The survival rate was high for both A‐EXP (79%) and B‐FFA (93.5%). B‐FFA fish had the highest specific growth rate (1.16 vs. 1.07; P < 0.05), and were heavier than A‐EXP fish (321 ± 40 g vs .239 ± 44 g; P < 0.01). Rearing conditions did not affect blood metabolites, except for glucose concentrations, which were higher in C‐WID (P < 0.05). The meat quality traits showed that reared groups were fatter (2.8–3.2%) than C‐WID (0.94%); total n‐3 fatty acids (19.02–19.26%) were lower in reared groups than C‐WID (29.99%); and EPA + DHA were similar in all groups (15.1–16.61% vs. 27.99%). Despite the good growth and survival, the final mean weight was below that requested by the market (400–500 g). Future research efforts should focus on reducing the feed conversion rate (3:1).     

Scouting the application of sourdough to frozen dough bread technology

The use of sourdough, even in combination with cryoprotectant (skim milk, sucrose and trehalose), conventional additives (guar gum, diacetyl tartaric acid esters of monoglycerides, ascorbic acid), honey or fructose and glucose, in frozen dough technology was investigated. After frozen storage, the leavening performance of doughs, and the hardness and texture of breads were compared to those of an unfrozen dough, and to those of a conventional frozen dough. All frozen doughs showed a longer fermentation time and a lower volume increase, with respect to unfrozen dough. When sourdough was combined with cryoprotectant, honey or both, the leavening performance improved compared to the use of sourdough alone. Compared to the conventional frozen dough, higher leavening performance was reached combining sourdough with cryoprotectant alone or together with honey. Sourdough combined with honey, fructose and glucose, honey and cryoprotectant, or conventional additives decreased bread hardness compared to the unfrozen dough bread and to the conventional frozen dough bread. Independently from the use of sourdough, conventional additives allowed to reach a specific volume not significantly different from that of unfrozen dough bread, and breads containing honey were characterized by low values of hardness and by high values of red index.     

Sweet Pepper (Capsicum annuum L.) Organic Seedling Production: The Role of Compost,Cultivar, and Protein Hydrolyzate

In the past decade, the increasing environmental concerns regarding the use of non-renewable resources, such as peat, for growing media production has led to a search for alternative materials as substrate components. Until now, compost represents the most investigated one. Despite the critical aspects related to compost use (i.e., its high pH, salinity, and potential content of toxic elements), partial peat substitution with this material represents an achievable objective. In this study, green compost was evaluated as a component of peat substrates for organic sweet pepper (Capsicum annuum L.) seedling production. Three compost rates (CR) were compared: 0 (peat without compost), 30, and 60% of compost v/v. Two pepper cultivars, one derived from a local (medium-Adriatic) germplasm (L) and a commercial hybrid (H), were tested. Furthermore, organic fertilizers based on hydrolyzed proteins, of animal (A) and vegetal (V) origin, were compared. Substrates were analyzed for characterization (pH, EC, nutrient contents, heavy metals). Seedling performances were evaluated in terms of size, biomass, nutrient uptake, and toxic element contents. Indices able to assess seedling resistance to transplant stress were also calculated. Results showed that CR60 treatment was able to produce seedlings with the same biomass of control. CR30, instead, assured the same chance to resist the transplanting stress of CR0. The performances of fertilizer A were significantly higher than those of fertilizer V. Local germplasm (L) showed the highest resistance to transplant stress, while H was more performing in nitrogen uptake. The risk of seedling contamination by toxic elements resulted negligible.     

Antimycotic effectiveness against dermatophytes: comparison of two in vitro tests

Seven antimycotic drugs (econazole, enilconazole, fluconazole, griseofulvin, itraconazole, ketoconazole, and miconazole) were tested against 36 dermatophyte strains (19 M. canis, 7 T. mentagrophytes, 5 M. gypseum, 2 M. cookei, 1 T. rubrum, 1 T. ajelloi, and 1 T. terrestre) isolated from animals, humans, and the environment. Two in vitro methods were compared: a micro-dilution test based on the CLSI M38-A method, and a disk-diffusion test. Fluconazole was not effective in vitro against the dermatophytes. Econazole and enilconazole were the most effective. Thirteen strains were griseofulvin-resistant. The correlation between the two methods was statistically significant for enilconazole, griseofulvin, itraconazole, and miconazole.