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Crayfish utilize aquatic plants as a food source and may concentrate pollutants, such as heavy metals. Monitoring the possible heavy metal presence in crayfish edible tissues is therefore important since crayfish can be part of the human diet. In this study we have analysed specimens of Cherax destructor of two different sizes coming from a crayfish farm, with respect to heavy metal (lead, copper, cadmium, chromium, zinc) concentrations in the muscle, hepatopancreas and exoskeleton. Furthermore, the metal concentrations were determined in water, sediment and in plants. Our data show that the contents of lead, copper, cadmium, chromium and zinc, are higher in the tissues with respect to water, indicating in some cases their bioaccumulation in Cherax destructor. The content of lead and zinc in sediment and plants the animals feed on, was higher than in tissues and organs, suggesting that biomagnification does not occur for these heavy metals. Copper and chromium show biomagnification in all tissues, while cadmium only in the hepatopancreas.

Abstract: A pilot project aimed at testing roe enhancement strategies based on offshore Paracentrotus lividus cultures was conducted off the south‐east coast of Italy (Apulia Region). Adult sea urchins were reared in sea cages located 700 m offshore at a depth of 12 m for 3 months. The animals were fed once a week on two formulated diets, prepared mixing nutrients with agar 20 g/Kg and differing only in terms of the protein source: anchovy flour (Diet A) or krill flour (Diet K). At the end of the rearing trial, the gonad somatic index of sea urchins fed on formulated diets significantly exceeded that of wild sea urchins. Total FAA content in the gonads of wild sea urchins and Diet A‐fed sea urchins was similar, whereas in Diet K‐fed sea urchins it was significantly higher. In terms of fatty acids, the gonads contained SFAs, MUFAs and PUFAs. In visual and sensory assessment of gonads by panel test and electronic nose, the gonads of reared sea urchins were rated as being of better size, while no differences were recorded for coloration, taste and odour. This study shows that under these experimental conditions, commercial‐grade Paracentrotus lividus roe enhancement can be achieved after 3 months in sea cages. [ABSTRACT FROM AUTHOR]

Satellite cells are adult stem cells located between the basal lamina and sarcolemma of muscle fibers. Under physiological conditions, satellite cells are quiescent, but they maintain a strong proliferative potential and propensity to differentiate, which underlies their critical role in muscle preservation and growth. MicroRNAs (miRNAs) play essential roles during animal development as well as in stem cell self-renewal and differentiation regulation. MiRNA-1, miRNA-133a and miRNA-206 are closely related muscle-specific miRNAs, and are thus defined myomiRNAs. MyomiRNAs are integrated into myogenic regulatory networks. Their expression is under the transcriptional and post-transcriptional control of myogenic factors and, in turn, they exhibit widespread control of muscle gene expression. Very little information is available about the regulation and behavior of satellite cells in large farm animals, in particular during satellite cell differentiation. Here, we study bovine satellite cells (BoSCs) undergoing a differentiation process and report the expression pattern of selected genes and miRNAs involved. Muscle samples of longissimus thoracis from Holstein adult male animals were selected for the collection of satellite cells. All satellite cell preparations demonstrated myotube differentiation. To characterize the dynamics of several transcription factors expressed in BoSCs, we performed real-time PCR on complementary DNA generated from the total RNA extracted from BoSCs cultivated in growth medium (GM) or in differentiation medium (DM) for 4 days. In the GM condition, BoSCs expressed the satellite cell lineage markers as well as transcripts for the myogenic regulatory factors. At the time of isolation from muscle, PAX7 was expressed in nearly 100% of BoSCs; however, its messenger RNA (mRNA) levels dramatically decreased between 3 and 6 days post isolation ( P<0.01). MyoD mRNA levels increased during the 1st day of cultivation in DM (day 7; P<0.02), showing a gradual activation of the myogenic gene program. During the subsequent 4 days of culture in DM, several tested genes, including MRF4, MYOG, MEF2C, TMEM8C, DES and MYH1, showed increased expression ( P<0.05), and these levels remained high throughout the culture period investigated. Meanwhile, the expression of genes involved in the differentiation process also miRNA-1, miRNA-133a and miRNA-206 were strongly up-regulated on the 1st day in DM (day 7; P<0.05). Analysis revealed highly significant correlations between myomiRNAs expression and MEF2C, MRF4, TMEM8C, DES and MYH1 gene expression ( P<0.001). Knowledge about the transcriptional changes correlating with the growth and differentiation of skeletal muscle fibers could be helpful for developing strategies to improve production performance in livestock. [ABSTRACT FROM AUTHOR]

A field trial conducted on the melon cultivar Huanghemi irrigated with saline water was carried out in Minqin County in the 2-year period, 2007 and 2008. In three irrigation treatments, different saline water concentrations were applied, that is 0.8 g l−1 (Control C), 2 g l−1 (Treatment S1) and 5 g l−1 (Treatment S2), reproducing the natural groundwater concentration in the county. The electrical conductivity of the saline water was as follows: 1.00, 2.66 and 7.03 dS m−1, respectively. The aims of the study were (i) to monitor water consumption and water potential, (ii) assess, during the whole crop cycle, some growth parameters and their relations for estimating the morpho-functional plant response irrigated with saline water and (iii) determine the ion concentration in different plant tissues to evaluate which mechanism the plant activates in the presence of high salt concentrations. Under salinity stress, the plants sustained the concentration of Ca, Mg and K, but at a level not sufficient to limit the Na adsorption. Therefore, the melon yield decreased and it was determined by a displacement of the ratio K/Na and by a lower [ABSTRACT FROM AUTHOR]

Epithelial cells are shed into milk during lactation, and although they generally reflect the cellular charcteristics of terminally differentiated luminal cells, previously the detection of more primitive cells was described in human milk where a cell population of epithelial lineage was detected expressing markers typical of progenitor cells. In this investigation, we report the development of flow cytometry analysis to allow mul-tiparametric assessment of mammary epithelial cells observed in milk. Cells collected from milk samples of 10 healthy dairy cows were directly analyzed for 6 different markers: CD45, CD49f, cytokeratin 14, cyto-keratin 18, presence of nucleus, and cell viability. Milk samples were collected in 3 different periods of lactation: early lactation (EL = d 0-30), mid-lactation (ML = d 90-120), and late lactation (LL = 210-250). Here we identify the differential expression of precursor or differentiated cell markers (or both) in mammary epithelial cells present in bovine milk. Myoepithelial cells, as indicated by cells staining positively for cytokeratin 14+/cytokeratin 18-, were observed to increase from EL to LL with a high correlation with nuclear staining inferring potential proliferative activity. Furthermore, a significant increase in CD49f+ and cytokeratin 14+/cy-tokeratin 18+ positive cells was observed in LL. This assay is a sensitive approach for evaluating the variations in the frequency and features of living epithelial cells, whose reciprocal balance may be significant in understanding mammary gland cellular function throughout lactation. These observations suggest that mammary epithelial cell immunophenotypes could be investigated as biomarkers for mammary gland function in dairy cows. [ABSTRACT FROM AUTHOR]