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The aim of these studies was to evaluate the in vivo and post-mortem performances of Marchigiana and Romagnola cattle. The results provide updated information that suggest that the selection index of some parameters should be revised to improve the dressing, which is one of the limitations of these breeds.

Myostatin or growth and differentiation factor 8 (MSTN or GDF8, respectively) is a member of the transforming growth factor-β superfamily that acts as a negative regulator of skeletal muscle development and growth. The myostatin encoding gene (MSTN) and the 5’ regulative region in different species has been investigated. The MSTN gene consists of three exons and two intronic regions. In cattle, the gene has well-characterized mutations determining phenotypes with increased muscle mass. In a previous study, by alignment of nucleotide sequences of PCR products of horse MSTN gene, we identified some SNPs of which two T>C transitions in the promoter of the gene. The aim of this work is to study in different horse breeds the frequency of the polymorphism located 516 nt upstream of the ATG start codon. This SNP is within a TATA box sequence (NATAAAA, where N= T or C) and the comparative sequence analysis of mammals myostatin gene promoters reveals that this TATA-box motive is conserved in position and sequence among some species including cattle, sheep and goat. The point mutation is not recognised by restriction enzymes, then the genotyping was done by restriction site insertion-PCR. The primer pair was designed on the basis of the obtained nucleotide sequences. The reverse primer was modified and designed with a single nucleotide mismatched with respect to target sequence to introduces an SspI artificial restriction site when the T nucleotide occurred. The PCR products of 203 bp were digested and the resulting fragments were resolved on 3.5% agarose gel. Two hundred and six samples of DNA belonging to 18 horse breeds (Bardigiano, 20; Breton, 5; Criollo, 10; Esperia Pony, 4; Haflinger, 9; Italian Heavy Draught Horse, 24; Italian Saddle, 21; Italian Trotter, 16; Lipizzan, 11; Maremmano, 13; Murgese, 12; Norico, 10; Purebred Spanish Horse, 10; Salernitano, 12; San Fratellano, 3; Tolfetano, 7; Thoroughbred, 11 and Ventasso Horse, 8) were genotyped. The T allele occurs in all the breeds. The C allele, which eliminates TATA box motif, was detected in 11 breeds and its value frequency ranged from 0.006 (Thoroughbred) to 0.400 (Norico). The homozygous C/C genotype was detected in Haflinger, Bardigiano, Norico and Tolfetano breeds. The presence of the polymorphism within a conserved region of promoter of horse myostatin gene could affect expression gene. This marker could be used for association studies with performance traits in horses.

Microbial spoilage is a major problem in grains or feedstuffs because it induces nutritional losses, formation of mycotoxins or potentially allergenic spores and in the end production of off-flavours. There is the need to find a method to conveniently assess the fungal growth in food and feed at every stage and after every technological process, as the detection of volatile compounds of fungi produced during primary and secondary metabolism. This paper presents the results of the analyses of some volatile compounds produced by Aspergillus ochraceus and Aspergillus parasiticus grown on maize. Moulds were cultivated on Czapek agar and on maize, previously sterilized by ultraviolet rays, in Erlenmeyer flasks closed with a Whatman bug stopper. Four samples for every substrate and mould were incubated at 26°C (A. ochraceus ) and 24°C (A. parasitucus) during 16 days. On day 8 and on day 16 of the trial, the headspace of the flasks containing the volatile metabolites was sampled with a Solid Phase-Microextration (SPME) equipped with adsorbent Carbowax PDMS fibre (Supelco, USA). Headspace samples were analysed using a gas-chromatograph HRGC- Mega 2 series 8560 (Fison Instruments, Italy) equipped with a split- splitless injector and a flame ionisation detector (FID). Separation of compounds of interest were done using a 30m x 0.25mm I.D. mm df capillary column TR-WAX with the following parameters: injection mode was splitless for 300 sec, injector temperature was 250°C, initial oven temperature 45° C, then raised at 3° C/min to 80°C, and kept for 20 min, then it was programmed at 2°C/min to 176° C followed by the raise al 10°C/min to 240°C and then kept for 20 min. The detector temperature was 260°C. The carrier gas was helium. Volatile compounds were identified by comparing their retention times to those of pure standards. The metabolites produced on Czapek agar by A. ochraceus were 3-Octanone, 1-Hexanol, 1-Octen-3-ol and 1-Butanol, by A. parasiticus only 3-Octanone and 1-Hexanol, while the metabolites on maize were 3-Octanone and 1-Hexanol by A. ochraceus and 3-Octanone, 1-Hexanol and 1-Octen-3-ol by A. parasiticus. The incubation time did not affect off flavour production in disagreement with the results from other authors (Börjesson, 1993; Magan and Evans, 2000). The two Aspergillus species did not show different volatile metabolites when cultivated on Czapek agar. Conversely, 1-Octen-3-ol was observed on maize substrate contaminated by A. parasiticus. The results of this analytical method open many possibilities to the employment of instruments, as electronic noses, for mould control in food and feed.