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The main objectives of this study were (i) to investigate the best fitting model for the genetic analysis of type traits and (ii) to estimate the genetic parameters of 4 composite (body size, muscularity, body shape, and udder) and 22 individual type traits between and within the two strains of the Valdostana dual purpose breed: the Aosta Red Pied (ARP; n =25,183 records) and the Aosta Black Pied and Chestnut (ABP-CHES; n =14,701 records). All type traits were scored from 2000 to 2012 on primiparous cows using a 1 to 5-point scale system. A model comparison was undertaken by considering the Akaike Information Criterion values obtained from the analysis, producing a final model that took into account the effects of herd-year-classifier, days in milk, age at calving as fixed and the animal additive genetic effect as random. Heritability estimates obtained through single trait animal model analysis varied from 0.03 for thinness (in both strains) to 0.32 (ARP) and 0.29 (ABP-CHES) for stature. Medium-low heritability estimates were obtained for individual muscularity traits (0.22 for ARP and 0.13 for ABP-CHES), and for individual udder type traits (0.12 on average in both Valdostana strains). The highest genetic correlations between composite traits were for muscularity with body shape in both Valdostana strains (0.55 for ARP and 0.52 for ABP-CHES). Different and opposite values of genetic correlations were found for the composite body shape and the composite udder traits (0.13 for ARP and –0.25 for ABP-CHES; P <0.01), probably due to the different breeding purposes set up for the two Valdostana strains. Regarding the individual type traits, for the ARP strain the highest genetic correlation was 0.97 (between thigh, buttocks side and rear view), whereas for the ABP-CHES strain it was 0.98 (between stature and body length), meaning that improving one trait of each pair led to a positive variation in the other. Most of the genetic correlations between the individual muscularity traits and the individual udder traits were negative, especially those involving udder volume (from –0.19 to –0.42 in ARP, and from –0.17 to –0.41 in ABP-CHES; P <0.01), indicating a substantial antagonistic situation of type traits related to dairy and beef traits. In conclusion, the selection for the dual purpose in local breeds such as in Valdostana cattle implies a thorough consideration of opposite morphological traits. [ABSTRACT FROM AUTHOR]

Any bacterial strain to be used as starter culture should have suitable characteristics, including a lack of amino acid decarboxylase activity. In this study, the decarboxylase activity of 76 bacterial strains, including lactic acid bacteria and grampositive, catalase-positive cocci, was investigated. These strains were previously isolated from European traditional fermented sausages to develop autochthonous starter cultures. Of all the strains tested, 48% of the lactic acid bacteria strains and 13% of gram-positive, catalase-positive cocci decarboxylated one or more amino acids. Aminogenic potential was strain dependent, although some species had a higher proportion of aminogenic strains than did others. Thus, all Lactobacillus curvatus strains and 70% of Lactobacillus brevis strains had the capacity to produce tyramine and β-phenylethylamine. Some strains also produced other aromatic amines, such as tryptamine and the diamines putrescine and cadaverine. All the enterococcal strains tested were decarboxylase positive, producing high amounts of tyramine and considerable amounts of β-phenylethylamine. None of the staphylococcal strains had tyrosine-decarboxylase activity, but some produced other amines. From the aminogenic point of view, Lactobacillus plantarum, Lactobacillus sakei, and Staphylococcus xylosus strains would be the most suitable for use as autochthonous starter cultures for traditional fermented sausages. [ABSTRACT FROM AUTHOR]