EN
The aim of the study was to determine the bacterial contamination of lamb carcasses in relation to the number of slaughtered animals during a day of slaughtering. The investigations were conducted on carcasses derived from a slaughterhouse that had accreditation for market production. In the investigated slaughterhouse the slaughter of the animals is carried out in one cycle, during one day of the week (most frequently on Mondays). The average number of animals slaughtered at the facility comes to 164 lambs. In order to determine the general number of aerobic bacteria, bacteria from the Enterobacteriaceae family and fecal streptococcus, 32 carcasses were examined (8 from each slaughter cycle); in order to determine the presence of Salmonella rods, 50 carcasses were examined (12 in 3 slaughter cycles and 14 in the fourth). Determining specific groups of microorganisms was conducted in accordance with Polish Norms (PN). Samples for examination were collected by the destructive and non-destructive methods (swabbing technique with sterile cotton swab) from the chuck steaks, saddle, brisket and thigh in accordance with PN. Each daily slaughter cycle was divided into 4 phases. In phase I the number of slaughtered animals did not surpass 25% of the average number of animals scheduled for slaughter in a given day, in phase II - the number was within the 51-60% division, in phase II - the number was within 61-74%, and in phase IV it was always at a level above 75%. In every phase samples were gathered from 2 carcasses (n = 8). In order to calculate the logarithmic daily average for the examined slaughter cycles (days) the results gained for the samples gathered in the II, III and IV phases of slaughter (n = 6) were taken into account. The obtained results were statistically analyzed with the average value and standard deviation calculated. The variability factor was determined on the basis of an analysis of the variance through the application of T-Tukey’s multiple confidence intervals for p ≤ 0.05. The investigation confirmed that the order of the slaughter of lambs in the course of the slaughter day does not significantly influence the level of the general number of bacteria on the surface of the examined carcasses. The results demonstrated that the general contamination of the lamb carcasses with aerobic bacteria vacillated from 8.0 × 10² jtk/cm² (phase III) to 2.9 × 10³ jtk/cm² (phase I). Nor were essential differences between specific slaughter phases confirmed within the range of the general number of microorganisms. The contamination was within the division of 7.5 × 10² (2.87 log) to 2.0 × 10³ (3.34 log) jtk/cm². The obtained logarithmic daily averages of contamination did not exceed boundary values for the number of microorganisms (m) determined for the hygiene standard for the sheep slaughter process in the order of the Commission 2073/2005. Bacteria from the Enterobacteriaceae family were confirmed in 18 samples (56.25%), and fecal streptococcus in all the examined samples. No significant differences were demonstrated in the levels of carcass contamination regarding the enumerated microorganisms at any specific phases of the daily slaughter cycle. The lowest contamination, which amounted to 25 jtk/10 cm² in the case of Enterobacteriaceae and 10 jtk/cm² in the case of enterococci, was determined in phase III; the highest - which amounted to 25 jtk/10 cm² and 5.0 × 10¹ jtk/cm², respectively - was determined in phase I. In most of the cases no influence of the day (cycle) in which the examinations were conducted upon the level of contamination of the carcasses with the enumerated microorganisms was confirmed. Only in the fourth (bacteria from the Enterobacteriaceae family) and in the second cycles (Enterococcus bacteria) a significantly lower level of contamination was confirmed in comparison with the first cycle. The logarithmic daily averages of contamination with these microorganisms ranged from 0.2 to 0.96 log jtk/cm² (15 jtk/10 cm² - 9 jtk/cm²) as well as 0.76 - 1.76 log jtk/cm² (6 - 5.8 × 10¹ jtk/cm²), respectively. Likewise in the case of bacteria from the Enterobacteriaceae family the logarithmic daily averages did not exceed boundary values for the number of microorganisms (m) determined for the hygiene standard for the sheep slaughter process in the order of the Commission 2073/2005. In none of the examined samples were Salmonella rods detected. The conducted study demonstrated no influence stemming from the number of slaughtered animals during the course of the slaughter day on the level of bacterial contamination on the surface of carcasses. This results from following the procedures and principles of the HACCP system as well as a properly conducted sanitary-veterinary supervision of the investigated slaughter house.