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BACKGROUND: Conflicting results about the effect of modified atmosphere packaging (MAP) rich in CO2 on the quality of different kinds of meat products are present in the literature. In this study, the degree of lipid degradation and the sensory characteristics of ripened sausages packed in modified atmosphere at three different carbon dioxide (CO2) concentrations were evaluated during 5 months of storage. RESULTS: The degree of hydrolytic degradation of the lipid fraction was found to decrease with increasing CO2 concentration. Similarly, oxidative phenomena occurred at a lower rate when the CO2 concentration increased. The variations in CO2 concentration influenced the perception of rancid flavor in the examined sausages. CONCLUSION: An increase in CO2 concentration in MAPs lowed down the evolution of lipid oxidation owing to the minor extent of hydrolytic degradation, whose products have pro-oxidant activity. This effect was more evident in the first 2 months of storage. [ABSTRACT FROM AUTHOR]

The present paper reports a research on reproductive parameters and larval rearing of red drum (Sciaenops ocellatus) maintained in captivity for the first time in Europe. Red drum juveniles were obtained from United States in the late 90s. In early January 2013, 40 in total male and female red drums ranging from 34 to 47 cm in length were held in a 25 m3 rectangular tank with a closed recirculating system with a water flow of 6000 L/h, located in Lesina (FG) fish farm (Southern Italy). Water temperature and salinity ranged between 21.0 and 28.8°C and from 25 to 27 g/L respectively. The fish were fed commercial feed pellet (46% protein) at 1.1% of body weight daily. Sexual maturation occurred during the natural breeding season of red drum. Approximately 43 spawns were recorded by the end of July and continuing to mid-September, with mean number of 66.5 millions of eggs collected overall on spawn period. Batch fecundity (3.325*106 ova per female) and relative fecundity (361.41 ova/g body weight) were calculated. Fertilisation rate was 30 to 80%. Larvae were hatched at a mean total length of 2.40±0.33 mm and showed a gradual increase in size of approximately 0.378 mm/day for the first 40 day after hatching (DAH). Cannibalism was observed as larger larvae preyed on smaller ones; to limit the phenomenon red drum population was selected for size at 35 DAH. Reliable information on fecundity and larval stage is essential for encouraging Sciaenops ocellatus farming also in Mediterranean countries. [ABSTRACT FROM AUTHOR]

This experiment was conducted to evaluate the effects of different levels of sweet orange (Citrus sinensis) peel extract (SOPE) on humoral immune system responses in broiler chickens. Three hundred 1-day broilers (Ross-308) were randomly allocated to treatments varying in supplemental SOPE added in the drinking water. The experimental groups consisted of three treatments fed for 42 days as follows: a control treatment without feed extract, a treatment containing 1000 ppm of SOPE and a treatment containing 1250 ppm of SOPE. All treatments were isocaloric and isonitrogenous. Broilers were vaccinated with Newcastle disease virus (NDV), avian influenza (AI), infectious bursal disease (IBD) and infectious bronchitis virus (IBV) vaccines. Antibody titer response to sheep red blood cells (SRBC) was higher in the group fed 1250 ppm of SOPE (P < 0.05) as well as for immunoglobulin G (IgG) and IgM. Similarly, antibody titer responses to all vaccines were constantly elevated (P < 0.05) by SOPE enrichment in a dose-dependent manner. Relative weights of spleen and bursa of Fabricius were unaffected by treatments. Dietary SOPE supplementation may improve the immune response and diseases resistance, indicating that it can constitute a useful additive in broiler feeding. Thus, supplying SOPE in rations may help to improve relative immune response in broiler chickens. [ABSTRACT FROM AUTHOR]

The article focuses on a study of male germ cell proliferation and apoptosis of captive-reared Atlantic bluefin tuna (ABFT) thunnus thynnus during its reproductive cycle. Topics discussed include increase of germ cell apoptosis when spermatogenesis occurred from April to May, temporal overlapping between spermatogenesis in wild and captive ABFT, and gonadotropins and steroid hormones in mammals as a survival factor that prevents germ cell apoptosis.

In the present study, cytotoxic effects of the polycyclic aromatic hydrocarbons benzo[a] pyrene (B[a]P) were investigated in Sparus aurata hepatocytes primary cultures after acute and chronic exposure. Cells were treated with a wide range of B[a]P doses (1 pg/mL to 100 μg/mL) for 24, 48 and 72 h. B[a]P toxicity was quantified in sea bream hepatocytes by MTT assay and immunofluorescence analysis of apoptosis after the various exposure periods, in order to evaluate the hepatic damage and toxicity range. Results showed three cytotoxic responses: B[a]P cell death for primary necrosis after exposure to high concentrations for short times, apoptosis induction with the use of sublethal doses and cell proliferation allied with neoplastic foci formation after exposure to low concentrations for long times. This responses provided an interesting correlation between the damage caused on hepatocytes and the metabolism of this toxic compound, to date mainly studied in vivo. Additionally, the statistical analysis revealed that the effects of time and dose were significant for both parameters and especially the time was extremely significant (P<0.0001), in fact B[a]P induced damage that increased over time. Our findings demonstrated and confirmed that S. aurata is a very sensitive species to B[a]P exposure since adverse effects were found at all tested doses. Furthermore, the new in vitro animal model can be considered a useful tool for studying the cellular effects induced by any contaminant harmful for farmed fish. [ABSTRACT FROM AUTHOR]

As its Greek name suggests, neuroglia is the glue of the nervous system, simply referred to as non-neuronal cells, with supporting functions for neurons in the central nervous system (CNS) of mammalian and lower vertebrates. Recent advances in stem cell biology have redefined new functions. In fish, neuroglial cells have been described as supporting cells, and as such require further investigation. Approximately 283 cell lines have been obtained from fish worldwide, yet none from the brain of Sparus aurata, neither in cell lines nor as primary culture. We describe a novel reproducible in vitro neuroglial marine model for establishing primary neuroglial cell cultures by dissociating the whole brain of seabream juveniles. Proliferating neural stem cells produced alongside three generating lineages (neuronal precursor cells, astroglial precursor cells and oligodendroglia precursor cells) developed neurons, astrocytes and oligodendrocytes, respectively. The radial glia, finely described by morphological studies and immunochemical antigen expression, showed a particular spatial distribution, giving rise simultaneously both to astrocytes and neuronal precursors within a highly proliferative assemblage. Radial glial cells were assessed by glial fibrillary acidic protein (GFAP) and vimentin reactivity, astrocytes by GFAP, neurons by the neuron-specific markers for ubiquitin carboxy-terminal hydrolase 1 (UCHL1) and intermediate filament associated protein (NF). Myelinating oligodendrocytes were immunostained with anti-myelin basic protein (MBP) and anti-04. Findings suggest that seabream neuroglial cells at 3-4 weeks of culture proliferation acquire neuroglial differentiation and oligodendrocyte maturation with myelination, suggesting that mixed neuroglial cultures accelerate maturation of oligodendrocytes and regenerate CNS injury in fish. [ABSTRACT FROM AUTHOR]

Among all known mycotoxins, aflatoxin B1 (AFB1) has been one of the most studied for its hepatotoxic, carcinogenic, mutagenic, teratogenic and immunosuppressant effects. However, there have only been a few metabolic and toxicological studies on aflatoxins in farmed Sparus aurata and these have been restricted to in vivo trials. This study aimed to examine the effects of acute and chronic AFB1exposure on CYP1A and GST enzymes induced in vitro on S. aurata hepatocytes by immunoblot analysis, and to carry out apoptotic studies on the cytotoxic effects leading to cell death. Immunofluorescence analysis revealed that cell damage was not reversible but permanent, as the cellular repair systems were unable to recover from the induced toxic insult. We detected several CYP1A bands and showed an indirect correlation between induction of CYP1A with dose and time of exposure. The decrease in expression of CYP1A over prolonged exposure times, along with high toxic concentration, could be related to the lethal damage observed on hepatocytes under contrast phase and immunofluorescence analysis. A particular pattern of expression was found for GST isoforms upon AFB1 exposure, identifying two different kinds of toxic insult for each isoform profile. The 65 KDa and the 49 KDa bands were suggestive of markers of acute and chronic response, respectively. Interestingly, apoptosis induction, considered an early DNA lesion, was found to be associated with chronic damage along with low toxic concentration. The new cell model from S. aurata has been proven to be a useful and valid tool to be used in the further investigation of the modulated response of liver phase I and II enzymes to AFB1. [ABSTRACT FROM AUTHOR]

The present study was carried out in order to investigate the effects of the mannanoligosaccharide (MOS) and fructooligosaccharide (FOS) on sharpsnout seabream, Diplodus puntazzo in the context of partial fish meal substitution by soybean meal. One-hundredforty- four sharpsnout seabream of about 100 g initial body weight were randomly divided in 12 experimental tanks (180 litre each). Testing conditions included 12 fish per tank, with triplicate tanks for treatment. The experimental period lasted 114 days. Average water temperature was 21.9±1.6°C, salinity was 30.0‰ and pH ranged from 7 to 8. Four isonitrogenousisolipidic diets were tested: a control diet (FM) with fish meal as the sole protein source; a second diet (SBM) with approximately 40% of the protein supplied by soybean meal. The remaining two diets were formulated adding 8 g of MOS and FOS per kg of the SBM diet respectively. Average final weight, specific growth rate, feed conversion ratio and protein efficiency ratio remained unaffected by partial fish meal substitution and by MOS or FOS supplementation. Also apparent digestibility coefficients values for organic matter, protein, lipid and energy were not significantly affected by dietary treatment. [ABSTRACT FROM AUTHOR]