-In this study enumeration of bacterial cells in raw sheep's bulk milk by an automated flow cytometry method (Bactoscan FC) was evaluated. The results were discussed with respect to the results obtained by the analysis of cow's milk. Within-laboratory reproducibility, which depended on the counting level, was slightly worse than that of raw cow's milk (valued in the interval > 50 Individual Bacterial Cell (IBC)·µL -1 ). In routine procedure, if preceding samples had counts > 20 000 IBC·µL -1 , then this was observed to increase the count of the following sample significantly in many cases ("carry-over"). Bactoscan counts were moderately enhanced with increasing numbers of somatic cells in sheep's milk. However, this trend was indicated only in samples with lower plate counts (< 10 5 colony-forming units (CFU)·mL -1 ). The regression equation between the results of the anchor plate method and the Bactoscan method was computed from the sample set which represented sheep's milk production in Slovakia during 2004 (data between percentiles 1 and 99, n = 877): log 10 CFU·mL -1 = 1.088 log 10 IBC·µL -1 + 2.292; with an accuracy of the estimate, expressed as standard deviation of regression s y,x = 0.305 log 10 CFU·mL -1 . The actual regression for raw cow's milk was verified, introducing both raw cow's milk samples and raw sheep's milk samples. The transformation of IBC·µL -1 to CFU·mL -1 realised by various published conversions was evaluated by testing of the parallelism of the regression lines and also by comparison of obtained differences on a model data set. The conclusions support the requirement to set up a special conversion for the intended field of application at any time. Résumé -L'application de la cytométrie de flux pour déterminer la qualité bactériologique du lait cru de brebis en Slovaquie. Dans cette étude, la numération des cellules bactériennes a été évaluée dans le lait cru de brebis de grand mélange par la cytométrie de flux automatisée (Bactoscan FC). Les résultats ont été comparés à ceux obtenus sur le lait de vache. La reproductibilité interne au laboratoire augmentait avec le niveau de la numération et était légèrement inférieure à celle obtenue sur lait cru de vache (pour les valeurs > 50 cellules bactériennes individuelles (CBI)·µL -1 ). La méthode de routine a montré que si les échantillons précédents avaient un niveau de contamination > 20 000 CBI·µL -1 , cela pouvait fréquemment augmenter significativement les valeurs dénombrées dans l'échantillon suivant ("carry over"). L'augmentation des cellules somatiques dans le lait de brebis entraînait une légère augmentation des valeurs de dénombrements par Bactoscan. Cependant cette tendance n'a été observée que dans les échantillons ayant les plus faibles niveaux de dénom-brements sur boîte (< 10 5 unités formant des colonies (UFC)·mL -1 ). L'équation de régression entre les résultats de dénombrements sur boîte et de dénombrements par Bactoscan a été calculée à partir de l'ensemble des échantillons représentant la production du lait de b...
The work is focused on the evaluation of seasonal dynamics of the total count of microorganisms in sheep's milk and on the proposal of developing cut-off values for standard limitation for the next fifteen years for hygienic safety support. The total count of microorganisms was measured between years 2012-2014 (n = 4,746). The results were statistically evaluated using medians, geometric means, arithmetic means, means of log values (log 10 ) and standard deviations for the cut-off limit determination. This model was patterned on the maximum of total count of microorganisms in the tested percentiles 95 (statistical conventional interval), 91, 90, 80 and 70% and on the result of medians (from 109 to 148 × 10 3 cfu/ml). These cut-off limits were divided into three classes (I to III) of standard quality, and the model of dynamics for their gradual implementation time was created as follows: initiation period (class I = ≤ 800; II = from 801 to 1,300; III = 1,301 to 4,000; non-standard = > 4,000 × 10 3 cfu/ml); second period (class I = ≤ 550; II = 551 to 800; III = 801 to 1,300; non-standard = > 1,300 × 10 3 cfu/ml); third period (standard class = ≤ 800 × 10 3 cfu/ml); fourth period (standard class = ≤ 550 × 10
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