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The aim of this study was to evaluate the effects of the administration of a species-specific probiotic (Lactobacillus animalis sb310, Lactobacillus paracasei subsp. paracasei sb137 and Bacillus coagulans sb117 in a 30:35:35 ratio, respectively; 1.8 × 10 10 cfu/g of powder) on gut microbial balance, immune response and growth performance of Holstein female calves during the first month of life. twenty-two calves were divided into two experimental groups from 2 to 28 days of life: control (c), fed with milk replacer and concentrate as a basal diet, and treatment (t), fed c diet plus 1 g/calf/day of probiotic powder for the first month of age. Faecal and blood samples were individually collected and analysed weekly. individual faecal score was recorded daily and general health score was calculated at the end of the trial. cell-mediated immune response was evaluated by skin test at 7 and 28 days of life. milk replacer and concentrate intake were recorded daily, while body weight and biometrical parameters were recorded at 2, 8, 14, 21 and 28 days of life, thus average daily gain and feed conversion rate were calculated. During the first week of treatment, lower blood eosinophil percentage (0.05% vs. 0.22%; P≤0.01) was found in T group, while basophils were higher in T than C group at the end of the trial (0.21% vs. 0.16%; P≤0.05). Higher faecal lactic acid bacteria (lab)/E. coli ratio on day 28 of life (3.73 log CFU/g vs. 2.02 log CFU/g; P≤0.05) and lower incidence of diarrhoea were found in the treated group (63.30% vs. 70.71%; p=0.05). Body weight (48.92 kg vs. 46.92 kg; P≤0.05), total concentrate intake (14.77 kg vs. 12.56 kg on dry matter basis; P≤0.05), and heart girth (81.16 cm vs. 78.49 cm; P≤0.05) were significantly higher in T group. The administration of the probiotic during the first month of life improved gut microbiota and increased the growth performance and some biometric parameters of calves.

Fourteen vacuum packed cold smoked salmon products of different origin purchased in Italian retail were analysed at about half shelf-life (HSL) and at the expiry date (ED). On ED, eight on fourteen samples had concentration of total volatile basic nitrogen (TVBN) indicating spoilage (values >40 mg N ⁄ 100 g and up to 71.3 mg N ⁄ 100 g) and only five samples were not rancid (thiobarbituric acid reactive substances, TBARS <8 nmol ⁄ g). Total psychrotrophic count (TPC) at HSL was acceptable (<10 6 CFU ⁄ g) in most samples; at ED, in 13 samples, TPC was very high (range 1.2 · 10 6 -6.0 · 10 8 CFU ⁄ g) and Lactobacilli were the most representative bacteria. No pathogens were detected. Significant negative differences in declared weight (over 8%) were determined in nine samples. The two months shelf-life attributed to smoked salmon marketed in Italy proved to be, generally, too long and the consumer is at risk to buy a product in early stage of spoilage.Keywords Quality indicators, quality of cold smoked salmon, shelf-life of cold smoked salmon, volatile compounds.

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An investigation was carried out into the recovery from calf faeces of Bacillus coagulans spores added to the feed as probiotic. For this purpose, Bacillus coagulans spores (9 log₁₀ CFU g⁻¹) were given daily to 10 calves during the whole farming periods; another 10 calves acted as controls. Throughout the trial the faecal spore counts were significantly (P < 0.01) higher in the treated group than in the controls (averaging 2.1 x 10⁵ vs 3.7 x 10⁴ CFU g⁻¹). Bacterial cells were recovered from faecal samples and ribotyping matched the strain isolated from faecal sample to the clone administered to the animals. In addition, the recovered cells were found to maintain their functionality aspects of acid production, survival in artificial gastric juice and in the presence of bile, and attachment to human intestinal epithelial cells. The results further elucidate the fate of spore formers administered to calves, and this will help in the development of new species-specific nutritional strategies.

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We evaluated the effects of two additive mixtures (sodium ascorbate 1 g kg À1 , sodium citrate 1 g kg À1 and sodium acetate 1.75 or 2.5 g kg À1 ) on the microbiological and physical-chemical characteristics of non-prepacked beef burgers stored in air at 4°C or 12°C for 96 h. Total microbial count reached 7 Log CFU g À1 48 h later in treated samples at 4°C. The mixture containing the higher acetate concentration led to a smaller increase in Gram-negatives, in particular Pseudomonas (2 Log of difference towards control samples at 96 h); at 12°C, a 1.7 Log difference in Enterobacteriaceae was also shown. Total viable basic nitrogen was significantly lower in the treated samples at 12°C. The addition resulted in pH stabilisation and lower cooking loss and positively influenced the a* index of burgers at 4°C. Clearly, the use of these mixtures should not be a substitute of good hygienic practices and optimal storage conditions. Addition of organic salts to burgers S. Stella et al. 1015X,Y (P < 0.01); x,y (P < 0.05). Values from different storage temperatures were statistically considered separately.Addition of organic salts to burgers S. Stella et al.Addition of organic salts to burgers S. Stella et al.Addition of organic salts to burgers S. Stella et al.

ABSTRACT:In this study, 254 Escherichia coli isolates from faecal samples of veal calves were evaluated for antimicrobial susceptibility using the disk diffusion method. During the experimental period, six mass antibiotic treatments were administered to the animals (about one treatment per month). The active principles used were oxytetracycline, colistin, tylosin, doxycycline, chlortetracycline, and sulphonamides. An extremely high resistance prevalence (> 70%) towards penicillin, sulphonamide, tetracycline, ampicillin, and spyramicin was detected. Sixty E. coli isolates could be defined as multiresistant, showing resistance to at least 6 antimicrobial classes. Subsequently, we evaluated the inhibitory effect of a species-specific probiotic against multiresistant E. coli, showing its beneficial action with large inhibition halos for 76% of the isolates. This suggests the potentiality of the probiotic, putting in evidence a clear advantage of its use in veal calves nutrition, in particular during the first phases, when the animals are more susceptible to severe enteric infections by E. coli.