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The aim of the study was to determine the influence of the maintenance system of laying hens on the bacterial pollution of the egg shell surfaces of consumer eggs. Eggs derived from four acceptable maintenance systems of hens were selected for the investigations: caged, litter, free ranging, ecological, whose source was from the Lublin voivodeship and obtained during the spring and summer period (April – July). 200 eggs were examined, 50 from each of the examined maintenance systems. All the examined eggs belonged to the L weight class. The egg surface was calculated using Pagannelli et. al.’s formula: Ps = 4.835 × M⁰·⁶⁶². Next the egg was rinsed with a sterile liquid, attaining a 10⁻¹/cm² thinner egg shell surface, which was again thinned down by a tenth. In the examined material the following were determined: the general oxygen bacteria count, the number of proteolitic and psychrophilic bacteria, bacteria from the Enterobacteriaceae family, as well as micro-organisms of the Enterococcus and Staphylococcus type. The measurements were conducted according to Polish norms. The bacteria count (the units forming a colony) was presented in a decimal logarithmic form, and subsequently expressed as log jtk/cm² of an egg shell. It has been confirmed that the total number of oxygen bacteria on the eggs was: from caged hens log 4.95 jtk/cm²; litter, log 5.35 jtk/cm²; free ranging, log 5.25 jtk/cm²; while from ecologically sustained hens, log 5.18 jtk/cm². The pollution on eggs from the caged maintenance system was significantly lower than those from the litter system. The proteolitic bacteria count on eggs from the maintenance systems was log 4.19 from the caged, log 4.71 from litter, log 4.72 from free ranging, and log 4.54 jtk/cm² from the ecological. Significant differences in pollution were confirmed in this type of bacteria between the caged and litter as well as free ranging maintenance systems. The psychrophilic bacteria pollution ranged from log 3.66 jtk/cm² of an egg shell in the caged system to log 4.02 jtk/cm² in the litter system. Significant differences in pollution in this type of bacteria occurred only between the caged and litter systems. The bacteria count of the Enterobacteriaceae family ranged from log 0.65 jtk/cm² on eggs derived from the litter system to log 1.64 jtk/cm² from hens kept in the free ranging maintenance system. Significant differences in pollution were determined in this type of bacteria between the litter, free ranging and both of the remaining examined maintenance systems. The bacteria count of the Enterococcus type in the case of the caged system was log 1.08, litter log 3.10, free ranging log 2.34 and log 2.08 jtk/cm² from the ecological maintenance system. Significant differences in bacteria of the Enterococcus type were determined between the caged and litter systems, and both of the remaining examined maintenance systems, which did not differ among themselves. In the case of the bacteria of the Staphylococcus type, the lowest pollution was determined on the egg shells derived from the caged system – log 2.73 jtk/cm², while the greatest in the free ranging (log 4.36) and litter (log 4.58 jtk/cm²) systems. It was confirmed that the maintenance system of laying hens has a significant influence on bacterial pollution of the consumer egg shells. The highest hygienic quality was demonstrated by eggs from the caged system, the lowest from the litter and free ranging systems.
The aim of the study was to analyse the results of post-mortem examinations of game carcasses conducted in Poland in 2000-2011 by the Veterinary Inspectorate. During that period, nearly 6 million game animals were shot, including mostly wild boars, roe deer and game birds. However, only 3 442 257 of them were examined post mortem by veterinarians. Lesions and qualitative changes were found in 65 970 carcasses (i.e. in 1.92% of the total number examined), of which 16 788, i.e. 25.45% (or 0.52% of all carcasses examined), were judged unfit for human consumption. The most lesions were found in boar carcasses (2.79%), and the least in deer carcasses (1.94%). The most common qualitative change, in both boar and deer carcasses (53.31% and 50.10%, respectively), was putrefaction, which was also the most frequent reason for qualifying carcasses as unfit for consumption (40.10% and 76.45% for boars and deer, respectively). The second most important group of lesions were parasitic diseases. In deer carcasses, the most frequent of these diseases was fascioliasis (14.63%), which, however, was not considered sufficient grounds for declaring meat unfit for consumption. In the muscle tissue of wild boars, trichinosis was found, constituting 15.38% of all lesions. In 2000-2011 trichinosis was detected in the muscle tissue of 3,748 boars (0.33%), and - after putrefaction - this disease was the second most important cause for rejecting boar carcasses as unfit for consumption. About 20% of boar and deer carcasses were judged unfit for consumption because of extreme emaciation. In 2000-2011, there was a considerable increase in the number of big game that were shot and presented for post-mortem examination, whereas the number of small game, especially hares, steadily decreased. The percentage of carcasses in which post mortem changes were found remained at a relatively constant level. An exception was 2007, when a marked increase in the number of carcasses with lesions was noted among both wild boars and deer. On the other hand, a notable decrease in the percentages of lesions and qualitative changes in deer carcasses was observed in 2008-2011, although the number of carcasses submitted to veterinary inspection did not change importantly. A vast majority of these changes resulted in deer carcasses being judged unfit for consumption. These facts may be explained by an improvement in the health status of deer combined with a rigorous performance of post-mortem examinations by official veterinary surgeons.
The research was aimed at evaluating the nutritional value of mechanically separated meat (MSM) of two different the poultry species and to compare it with the corresponding characteristics of hand-separated meat. The research was conducted on chicken and geese meat obtained by pressure separation (with a SIMO Meat Separator), in which muscle tissue is ground along with bones, cartilage, and sinews. The raw material for the production of MSM included backs, wings, necks, and trunks (except for breast muscles) of broiler chickens and slaughter geese, as well as whole goose carcasses that did not meet commercial standards. Samples were collected during 20 production cycles. The examination was conducted on chicken and goose MSM, as well as on hand-separated chicken and goose meat, which consisted of breast and thigh muscle samples. Hand-separated muscles were the control. The total protein content was determined by the Kjeldahl method, the fat content by the Soxhlet method, the water content by desiccation at 105°C, the calcium content by flame atomic absorption spectrometry with a Varian Spectra AA 2807S spectrometer, and the phosphorus content by spectrophotometry with a Shimadzu UV-1800 spectrophotometer. Fatty acid composition was determined by gas chromatography with a Varian CP 3800 chromatograph. The amino acid profile of mineralized proteins was determined with an AAA 400 amino acid analyser (Ingos Praha). The biological value of proteins was determined on the basis of their amino acid composition by calculating the chemical score (CS) and the essential amino acid index (EAAI). The significance of differences between the characteristics under analysis was evaluated by Tukey’s test at p ≤ 0.05. The chemical composition of MSM of chickens and geese showed significant differences. Chicken MSM contained significantly more proteins, water, and calcium, but less fat than goose MSM. Hand-separated meat had significantly higher contents of proteins and water, but lower contents of fat and calcium than both kinds of MSM. The two kinds of MSM did not differ significantly in their phosphorus content, which however was significantly lower (by 50%) than that in hand-separated meat. The content of most amino acids in proteins was significantly higher in chicken MSM than in goose MSM. The content of amino acids in both kinds of MSM was significantly lower than in hand-separated meat. This was also true about exogenous amino acids, which are particularly important for the biological value of proteins. Compared with the amino acid composition of model proteins, the proportion of exogenous amino acids in MSM was unfavourable from the point of view of human nutritional needs. Amino acids that limited (CS) the absorption of proteins were sulphur amino acids in the case of chicken meat (both mechanically and hand-separated) and aromatic amino acids in the case of goose meat. The content of saturated fatty acids (SFA) differed significantly between MSM and hand-separated meat, as well as between chicken and goose MSM. The same pattern was observed for polyunsaturated fatty acids (PUFA). Unlike mechanically separated and hand-separated goose meat, chicken and goose MSM differed significantly in their monounsaturated fatty acid (MUFA) content. Our own research revealed an unfavourable proportion of PUFA n-6 to PUFA n-3 in chicken MSM (18:1) and confirmed a high nutritional value of fat in goose MSM (8:1) and in hand-separated goose meat (8-9:1). Fat in chicken and goose MSM differed significantly in the proportions of SFA to MUFA and to PUFA The content of monounsaturated fatty acids was twice as high as that of saturated fatty acids both in goose meat and in MSM produced from it. Our own research demonstrated that the proportion of unsaturated fatty acids (UFA) to saturated fatty acids (SFA) in goose MSM is better than that in chicken MSM. The nutritional value of mechanically separated poultry meat is considerably lower than that of hand-separated poultry meat. An excessive use of mechanically separated poultry meat in the production of meat products may significantly reduce their biological value.
Celem pracy było oznaczenie zawartości selenu w wybranych tkankach koni rzeźnych oraz określenie jej zmienności w zależności od wieku i płci zwierząt. Materiał do badań stanowiły trzy mięśnie oraz narządy wewnętrzne (nerki, płuca i wątroba) pochodzące ze 117 tusz koni rzeźnych zakwalifikowanych do drugiej klasy jakościowej. W doborze materiału doświadczalnego uwzględniono zwierzęta obu płci oraz dwie grupy wiekowe: konie młode (od 6 do 18 miesięcy) i stare (od 10 do 13 lat). Pobrane próbki po wstępnym przygotowaniu poddano mineralizacji. Zawartość selenu w uzyskanych mineralizatach oznaczono przy użyciu spektrometru absorpcji atomowej ze wzbudzeniem elektrotermicznym i deuterową korekcją tła Zeeman, Spektra 220Z firmy Varian. Wykazano statystycznie istotne (p ≤ 0,01) różnice zawartości selenu pomiędzy wszystkimi badanymi tkankami. Najwięcej selenu stwierdzono w nerkach (0,487 ppm), istotnie (p ≤ 0,01) mniejszą zawartość tego pierwiastka oznaczono w wątrobie (0,177 ppm), a jeszcze mniejszą – w płucach (0,062 ppm). Najmniej badanego pierwiastka było w tkance mięśniowej (0,039 ppm). Uwzględniając wiek koni, w nerkach i mięśniach zwierząt młodych wykazano statystycznie większą (p≤0,01) zawartość selenu. Płeć miała niewielki wpływ na zawartość selenu zarówno w narządach wewnętrznych, jak i w mięśniach. Istotne (p ≤ 0,01) różnice dotyczyły jedynie nerek. Z trzech badanych mięśni najwięcej selenu oznaczono w mięśniu nadgrzebieniowym (m. supraspinatus), a nieznacznie mniej, ale w wymiarze statystycznie istotnym (p ≤ 0,01), w mięśniach: najdłuższym (m. longissimus pars thoracis) i półbłoniastym (m. semimembranosus). Różnice te dotyczyły jedynie mięśni zwierząt młodych. W grupie tej stwierdzono także istotne (p ≤ 0,01) różnice pod względem zawartości selenu w zależności od rodzaju mięśnia i płci. Najmniej selenu zawierały mięśnie zwierząt powyżej 10. roku życia. W tej grupie zwierząt nie wykazano istotnych (p ≤ 0,01) różnic pomiędzy badanymi mięśniami, a także nie wykazano istotnego wpływu płci na zawartość selenu.
The aim of the study carried out on ten young (10-week old) pigs of the native Polish Large White breed experimentally infected with a low dose of 300 invasive muscle larvae (ML) of Trichinella spiralis was intravital detection of trichinellosis using the E-S ELISA test, determination of a variation level of IgG antibodies against excretory-secretory (E-S) antigens of T. spiralis muscle larvae and finally, describing the intensity of T. spiralis larvae infection in selected muscles. The pig sera were collected at 7 and 9 days prior to the experimental infection with T. spiralis and at 9, 14, 20, 23, 25, 27, 30, 33, 37, 41, 46 days post-infection (d.p.i.). The anti-T. spiralis IgG antibodies were detected by a commercial E-S ELISA test (PrioCHECK Trichinella Ab). Average intensity of the T. spiralis infection in the examined muscles of pigs ranged from 1.52 up to 43.09 larvae/g. The studies revealed that the E-S antigen in the ELISA test did not show cross-reaction with the sera of pigs infected with Oesophagostomum spp. The ELISA assay did not recognize trichinellosis in pigs until 27 days after the T. spiralis infection. The anti-T. spiralis IgG antibodies were first detected on day 30 post-infection. A statistically significant increase of IgG antibodies against T. spiralis ML E-S antigens was first observed between days 27-30 (p<0.01) post-infection, and a further significant rise in the antibody level occurred between days 27 and 33 (p<0.01); 30 and 33 (p<0.01); 33 and 37 (p<0.05) following infection.
The research material included 96 slaughter rabbit carcasses. Half of them came from the animals managed in small-scale backyard farming units where animals were fed a natural ingredient diet, while the other half was from rabbits kept under commercial production conditions and fed commercial rabbit pellets. The thigh and saddle muscle samples were collected from each carcass to establish a content of ubiquinone (CoQ10) and crude protein along with its collagen level. Determination of tissue coenzyme Q10 (UQ10) was carried out by high-performance liquid chromatography with some modification. Crude protein concentration was estimated using Kjeldahl procedure, while total collagen content by the method of Stegemann modified by Hurych-Chvapil, using hydrolysis according to Möhler and Volley. Ubiquinone level in slaughter rabbit tissue ranged between 76 and 127 µg/g tissue. The studies indicated that rabbit rearing sy stem and muscle type are determinants of CoQ10 content. Meat of rabbits managed under the traditional backyard farming system exhibited higher CoQ10 concentration as compared to that determined in rabbits from the commercial rabbitry. Additionally, the CoQ10 level in the saddle was significantly higher than that in the thigh muscles, and the relationships was noted in both types of rabbit production systems. When the CoQ10 content was expressed per gram of fibrillar protein, there were not significant differences between saddle and thigh muscles. The correlation coefficient between ubiquinone and fibrillar protein averaged to 0.94. The studies also demonstrated a higher protein level in the saddle than in thigh muscles. However, no differences in protein concentration were reported in respect to the rabbit farming system. The protein composition in the saddle muscles, irrespective of a rabbit production system, revealed significantly lower collagen content compared to the proteins in thigh muscles. The obtained results and data from literature provide evidence that rabbit meat, especially from the traditional (organic) management system, is one of the best sources of animal protein and ubiquinone Q10.
The purpose of the research was to determine the presence and frequency of pathogenic microorganisms of the genera Salmonella, Listeria, and Campylobacter, and of coagulase-positive staphylococci on the surface of consumer eggs from different hen-housing systems. The research material consisted of 120 eggs, comprising 30 eggs from each of four farms using different housing systems: the battery system, the deep-litter system, the free-range system, and the organic system. The eggs were collected into sterile bags in the henhouse directly after being laid, before being marked. The presence of microorganisms was established in accordance with Polskie Normy (Polish Standards). No Salmonella rods were detected on eggs from any of the four hen-housing systems. Microorganisms of the genus Campylobacter were found on 4 eggs (13.13%) from the deep-litter housing system and on 3 eggs (10%) from the free-range system. Only on the eggs from the battery system, no bacteria of the genus Listeria were detected. These bacteria were found on 3 eggs (10%) from the deep-litter system, but the presence of L. monocytogenes was confirmed on only one of the three eggs. In the case of the eggs from the free-range system, bacteria of the genus Listeria were present on 15 eggs (50%), 3 of which (10%) were polluted with L. monocytogenes. The same microorganisms were also detected on 14 eggs (46.7%) from the organic system, but none of them were L. monocytoges. All eggs examined, irrespective of the housing system, were polluted with coagulase-negative staphylococci, whereas coagulase-positive staphylococci were detected on a single egg from the free-range housing system only. The research demonstrated that human pathogens can be found on the surface of consumer eggs from any housing system. The housing system has a statistically significant influence on the degree of pollution with these microorganisms. The battery system, in which only coagulase-negative staphylococci were found, appears to be the safest in terms of the pollution of eggs with pathogenic microflora. The possibility of eggs being polluted with human pathogens makes it highly advisable for consumers to wash eggs directly before use.
The aim of the study was to establish the variation in microbial contamination of quail eggshell surfaces depending on the frequency of hygiene-sanitary practices carried out in cages (washing, disinfection and fecal waste removal). The studies involved eggs collected from three quail breeding farms situated in south-eastern Poland and characterized with different frequencies of hygiene practices. From October to April, 50 eggs were collected from each farm at five different collection times, at 3-week intervals. The freshly laid eggs were collected in a sterile way directly from the cages, cooled and transported to the laboratory to be subjected to a rinsing treatment with a sterile solution technique to obtain 10–1/cm2 dilution of the eggshell surface. The obtained study material was evaluated for a total count of aerobic bacteria, numbers of proteolytic bacteria and bacteria from the Staphylococcus genus, counts of aerobic bacteria and microorganisms from the Enterobacteriaceae family, as well as the number of yeasts and moulds. As per entire egg surface, the presence of pathogenic microorganisms from the Salmonella, Campylobacter and Listeria genus were detected. The determinations were performed in accordance to Polish Standards. Relatively slight contamination of eggshell surfaces was established (from 4.7 × 102 up to 4.7 × 103 cfu/cm2 ), and its contamination level varied between the farms. Out of the microbial groups under study, Staphylococcus spp. constituted the predominant part of microbial flora (32.7-51.5%), yet only a single sample was found to harbor coagulase-positive staphylococci (Staphylococcus aureus subsp. anaerobius). The presence of neither moulds nor yeasts was confirmed on the shell of eggs collected from farm 1, while their counts on the eggs obtained from two other farms did not differ significantly and ranged between 0.8 × 102 and 1.2 × 102 . In two samples, microorganisms from the Listeria genus were recovered; however, the PCR studies did not confirm their belonging to the L. monocytogenes species. The presence of Campylobacter and Salmonella genus bacteria on the eggshells under study was not detected. It was found that frequency of hygiene-sanitary practices carried out at a farm had a significant effect on the level of microbial contamination of quail eggshell surfaces. The cleaning of cages (washing and disinfection) together with daily removal of feces considerably reduced microbial contamination of eggshells. The absence of bacterial pathogens of Campylobacter and Salmonella genus and L. monocytogenes on the studied eggshell surfaces and a low level of total microbial contamination indicate that quail eggs are safe for consumers on condition that sanitary regulations are observed.
The objective of the research was to determine the occurrence of microorganisms from the Salmonella spp. and Listeria spp. in raw and frozen (cooked) snail meat obtained from both, free-living population and farmed edible snails. The research material comprised the meat samples (25g each) collected from three snail species, i.e. Roman snail (Helix pomatia – HP), small brown garden snail (Cornu aspersum aspersum – CAA) and large brown garden snail (Cornu aspersum maxima – CAM). Roman snails came from natural environment and were harvested in the Wielkopolskia and Lower Silesia province area (region A and B, respectively). The Cornu genus snails were obtained from two different heliciculture farms located in the above mentioned provinces (farm A and B, respectively). In both farms, the snails were maintained under the mixed rearing system. The raw meat specimens taken from the edible portion of snail, that is the foot with collar and a fragment of mantle, were obtained after the snails were sacrificed in the laboratory. Whereas the frozen meat specimens came from the snail meat processing facility. The presence of Salmonella was analysed in a total of 300 samples, while Listeria in 240 ones. The studies also included pooled soil samples of 0.5 kg each collected from the polytunnels (the pre-fattening stage) and outdoor farming park plots (fattening stage). The studies for the Salmonella presence were performed in accordance to PN-EN ISO 6579:2003, whereas for Listeria in compliance with PN-EN ISO 11290-1:1999. Species identification of Listeria monocytogenes was made by the PCR technique. The Salmonella presence was not confirmed in any of a total of 300 specimens of raw and cooked snail meat under study. These pathogens were not isolated from the soil samples, too. The absence of these bacteria in the raw meat specimens indicates that salmonella do not occur in both, the natural habitat of Roman snails or environment of two farms producing Cornu genus snails. Bacteria of Listeria genus was detected in 101(42,1%) snail meat samples under investigation. This particularly high microbiota load was reported in raw meat as these bacteria contaminated from 60% (HP from region A and CAM from farm B) up to 75% (CAA from farm A) samples under investigation. Notably, a markedly lower (35%) percentage of specimens with listerie was established only in the Roman snail raw meat samples from the region B. The Listeria spp. presence was also stated in all the soil specimens. The thermal treatment of meat achieved the substantial reduction in the Listeria spp. load, yet it did not eliminate its presence. Frequency of listeria occurrence in the frozen meat specimens was from 1,6 (CAM from farm A) up to 6,5-fold (CAA from farm B) lower compared to raw meat. The PCR technique was used for the species identification of 15 selected strains, in that 11 from the raw meat specimens and 4 from the cooked meat. A total of 5 isolates were recognized as Listeria monocytogenes (2,1% of total specimens examined and 4,95% specimens with listeria burden). They came solely from the raw meat samples collected from the farmed snails, in that one from farm A (from CAA) and four from farm B (3 from CAA and 1 from CAM). Bacteria from the Salmonella and Listeria genera occur in the natural habitat of edible snails and this, pose a potential hazard to human health. Efficient implementation of control programs at the primary production is the first step that could largely limit the presence of these pathogens in farmed snails and consequently, in snail meat.
The study was aimed at determining the effects of diets containing snail meat as the sole protein source, on mandible quality in male Wistar rats. In the experiment, three different snail-based diets were tested and compared with a casein-based control diet. These included snail meat from Helix pomatia, Cornu aspersum maxima and Cornu aspersum aspersum. In all diets, the protein content amounted to 10% (as calculated on a dry weight basis). Forty male Wistar rats with an initial body mass of 50 g ± 2 were randomly allocated to one control and three experimental groups. After 28 days of experimental feeding, the rats were sacrificed. Their mandibles were isolated and investigated by densitometric (DXA), tomographic (pQCT) and morphometric methods. Moreover, the mechanical parameters (ultimate strength and Young’s modulus) of the mandibles were measured. The results revealed that snail meat as the sole source of protein significantly decreased the bone mineral density (BMD) and content (BMC) of the mandibles. Moreover, the tomographic analysis demonstrated that each type of snail-based diet had a negative influence on the bone cortical and trabecular compartments (which was especially noticeable in the decreasing pQCT parameters). The investigation of mechanical resistance of the mandibles also revealed lower values of the ultimate strength and Young’s modulus in the snail-based diet groups, compared with the casein group.
The aim of the study was to determine the variability in the chemical composition and nutritive value parameters of smoked and unsmoked short-ripened rennet cheeses and unsmoked long-ripened rennet cheeses produced by traditional methods. The raw material for the production of short-ripened cheeses was pasteurized cows’ milk obtained from a dairy, whereas the long-ripened cheeses were manufactured from raw cows’ milk obtained from the producer’s farm. All three varieties of cheese examined were produced with commercial dairy starter cultures. The material for the study was collected in winter, directly at the producers’ retail outlets in southern and eastern Poland. The basic chemical composition was determined according to the Polish Standards, whereas the amino acid profiles of proteins from the cheeses were determined by ion-exchange chromatography. The result analysis revealed significant differences between the different varieties of cheese in terms of their water content, ranging from 32.2% to 42.1%, as well as protein content, which varied from 25.6% to 31.6%. Fat levels ranged between 22.2% and 24%, whereas total ash content amounted to 5.1-5.8%. The significantly highest salt content was found in unsmoked short-ripened cheeses. In all three cheese varieties, the total exogenous amino acid content was comparable, ranging from 46.17 g to 47.36 g/100 g protein, and that of endogenous amino acids varied from 52 g to 53 g/100 g protein. The biological value of proteins was determined by calculating to the chemical score (CS), as described by Mitchell and Block, and the essential amino acid index (EAAI), as described by Oser. A comparison of the results with the standard chicken egg white proteins showed that the limiting amino acids for all varieties of cheese were methionine and cysteine. On the other hand, a comparison with the FAO/WHO-suggested pattern of amino acid requirements (1991) for all age groups over 1 year of age showed that the limiting amino acids were methionine and cysteine in smoked and unsmoked short-ripened cheeses, and treonine in long-ripened cheeses. Considering the chemical indices, such as CS and EAAI, it may be concluded that the traditional rennet cheeses produced in southern and eastern Poland have a favourable amino acid composition of proteins and a high nutritive value.
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