The gilthead seabream (Sparus aurata) is one of the main marine fish species cultured in Europe. In order to enhance the efficiency of aquaculture production, there is an increasing interest to develop selective breeding programs and molecular markers especially useful for tracing pedigrees without having to rear families separately. Here we describe 12 new polymorphic microsatellites loci, whose polymorphism was evaluated in a sample of 32 unrelated individuals. For each locus, the number of alleles vary from 4 to 23 alleles with mean expected and observed heterozygosity of 0.71 and 0.67, respectively. Two out of the 12 loci tested (SA5-E06 and SA3-G06) showed significant deviation from HWE after Bonferroni correction (P \ 0.0041), both with a large heterozygote deficiencies. None of the 12 loci showed significant linkage disequilibrium, following the Bonferroni correction (P [ 0.05; adjusted P = 0.0008).These set of microsatellites could prove very effective for parentage inference and stock differentiation studies.

This study aimed at examining and comparing the nutrient removal efficiency, biomass productivity and microbial community structure of two outdoor pilot-scale photobioreactors, namely a bubble column and a raceway pond, treating the liquid fraction of an agricultural digestate. Bacterial and eukaryotic communities were characterized using a metabarcoding approach and quantitative PCR. The abundance, composition, diversity, and dynamics of the main microbes were then correlated to the environmental conditions and operational parameters of the reactors. Both photobioreactors were dominated either by Chlorella sp. or Scenedesmus sp. in function of temperature, irradiance and the nitrogen compounds derived by nitrification. Other species, such as Chlamydomonas and Planktochlorella, were sporadically present, demonstrating that they have more specific niche requirement. Pseudomonas sp. always dominated the bacterial community in both reactors, except in summertime, when a bloom of Calothrix occurred in the raceway pond. In autumn, the worsening of the climate conditions decreased the microalgal growth, promoting predation by Vorticella sp. The study highlights the factors influencing the structure and dynamics of the microbial consortia and which ecological mechanisms are driving the microbial shifts and the consequent reactor performance. On these bases, control strategies could be defined to optimize the management of the microalgal-based technologies.

A study was conducted on two young Italian Holstein bulls obtained by embryonic splitting and, therefore, genetically identical. The andrological evaluation of the subjects revealed a significant difference in semen freezability, valued according to forward motility after thawing (57.34 vs. 46.92; P

The objectives of the present work were to verify whether simultaneous exposure to Hoechst 33342 and UV irradiation during sorting by flow cytometry may induce gene point mutations in bovine sperm and to assess whether the dye incorporated in the sperm may imply a mutagenic effect during the embryonic development. To this aim, high-resolution melt analysis (HRMA) was used to discriminate variations of single nucleotides in sexed vs. non-sexed control samples. Three batches of sorted and non-sorted commercial semen of seven bulls (42 samples) were subjected to HRMA. A set of 139 genes located on all the chromosomes was selected, and 407 regions of the genome covering a total of 83 907 bases were analyzed. Thereafter, sperm of one sexed and one non-sexed batch of each bull was used in in vitro fertilization, and the derived embryos were analyzed (n = 560). One hundred and thirty-three regions of the bovine genome, located in 40 genes, were screened for a total coverage of 23 397 bases. The comparison between the frequencies of variations, with respect to the sequences deposited, observed in the sexed and non-sexed sperm (843 vs. 770) and embryos (246 vs. 212) showed no significant differences (P > 0.05), as measured by chi-square tests. It can be concluded that staining with Hoechst 33342 and exposure to UV during sorting does not lead to significant changes in the frequencies of variants in the commercial sexed semen and in embryos produced in vitro with the same treated sperm.

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