Research Note: Antimicrobial resistance profile of Enterococcus spp. isolated from the eggshell of laying hens submitted to pharmacological treatment.

The occurrence of antimicrobial resistance in microorganisms isolated from eggshells, especially Enterococcus, might serve as a parameter to assess the selection of bacteria due to the use of drugs in the diet of laying hens. In order to evaluate the frequency and the antimicrobial resistance profile of Enterococcus spp. isolated from the eggshells, 225 Hy-line laying hens were submitted to a 25-d long trial. The treatments were the following: hens fed ration without antimicrobials (control) and groups that received oxytetracycline (10 mg kg-1), doxycycline (20 mg kg-1), lincomycin (50 mg kg-1), and enrofloxacin (10 mg kg-1) in the ration for 5 d. Six replications were analyzed per treatment, composed of a pool of 5 eggs each. They were collected before treatment and on days 3, 6, 15, and 25, totaling 150 samples. Eggshells were submitted to counts of Enterococcus spp., which were identified by proteomic analyses. Antimicrobial resistance was determined by the disk-diffusion test. It was observed that 97.3% (n = 146) of the samples were contaminated with Enterococcus spp. There were no differences (P > 0.05) in the bacterial counts between treatments on the same day of evaluation. E. faecalis and E. faecium were the most frequent on the eggshells of all treatments. Multiresistance to the four classes of antimicrobials was also verified in the isolated bacteria. A total of 83% of the Enterococcus isolates showed resistance to neomycin, which was not administered to the hens, demonstrating an environmental problem. Thus, feeding laying hens with diets added with antimicrobials induces drug resistance in Enterococcus spp., isolated form the eggshells.

Caracterização microbiológica de carcaças de frangos de corte produzidas no estado de Minas Gerais / Microbiological characterization of broiler carcasses produced in the state of Minas Gerais

In order to evaluate the microbiological quality of broiler chickens produced in Minas Gerais State, 240 samples of broiler carcasses from the five regions of the Minas Gerais State were collected, by official inspection services, for one year. The samples were submitted to counts of total and thermotolerant coliforms, coagulase-positive and negative Staphylococcus, besides Campylobacter spp., Listeria monocytogenes, E.coli O157:H7, and Salmonella spp. resource. The results showed the presence of total and thermotolerant coliforms in 34.2% and 13.5% of broiler carcasses evaluated, respectively. All tested samples were positive for Staphylococcus spp., 9.1% for Salmonella spp., 15.5% for Listeria monocytogenes, and 2.1% for Campylobacter spp. E.coli O157:H7 was not isolated from the samples.(AU)

Influence of cutting room temperature on the microbiological quality of chicken breast meat / Influência da temperatura da sala de cortes sobre a qualidade microbiológica da carne de peito de frango

The temperature control in the processing room is one of the major factors associated with the production of safe food with a satisfactory microbiological quality. A total of 288 samples of skinless chicken breast meat were placed in a cutting room, subjected to four different temperatures (12ºC, 14ºC, 16ºC and 18ºC) and collected to evaluate the influence of the room temperature on the microbiological quality during the cutting and boning of chicken breasts. Aerobic mesophilic microorganisms were counted to evaluate the environmental contamination. In addition, coliforms at 35ºC and 45ºC and Staphylococcus spp. were counted, and an analysis for the presence of staphylococcal enterotoxins and Salmonella spp. was performed to determine the microbiological quality of the meat. The results showed an increase in environmental contamination (P=0.01) with an increase in room temperature. However, no significant differences (P˃0.05) were observed in the meat cuts regarding the counts of coliforms at 35ºC and 45ºC, the count of Staphylococcus spp. and the presence of Salmonella spp. Moreover, no staphylococcal enterotoxins were detected in the samples analyzed. Thus, despite increasing the environmental contamination, the increase in the cutting room temperature did not affect the microbiological quality of the final product.(AU)

O controle da temperatura do ambiente de processamento é um dos principais fatores relacionados à produção de alimentos seguros e com qualidade microbiológica. Com o objetivo de avaliar a influência da temperatura ambiente durante o corte e a desossa da carne de frangos sobre a qualidade microbiológica dos produtos finais, foram coletadas 288 amostras de carne de peito de frango sem pele, obtidas em uma sala de cortes climatizada submetida a quatro diferentes temperaturas ambientes (12ºC, 14ºC, 16ºC e 18ºC). Para avaliação da contaminação ambiental, foi realizada a contagem de microrganismos mesófilos aeróbios e, para a avaliação da qualidade microbiológica da carne, foram realizadas a contagem de coliformes totais e termotolerantes, a contagem de Staphylococcus spp., a pesquisa de enterotoxinas estafilocócicas e a pesquisa de Salmonella spp. Os resultados encontrados demonstraram um aumento da contaminação ambiental (P=0,01) à medida que a temperatura da sala foi aumentada. Porém, nos cortes cárneos, não foram observadas diferenças significativas (P˃0,05) na contagem de coliformes totais e termotolerantes, na contagem de Staphylococcus spp. e na pesquisa de Salmonella spp. Também não foi detectada a presença de enterotoxinas estafilocócicas nas amostras analisadas. Foi concluído que, apesar da elevação da contaminação ambiental, o aumento da temperatura ambiente da sala de cortes não comprometeu a qualidade microbiológica do produto final.(AU)

Validation of an HPLC-UV method for the identification and quantification of bioactive amines in chicken meat / Validação de metodologia por HPLC/UV para identificação e quantificação de aminas bioativas em carne de frango de corte

A high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method was validated for the study of bioactive amines in chicken meat. A gradient elution system with an ultraviolet detector was used after extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Putrescine, cadaverine, histamine, tyramine, spermidine, and spermine standards were used for the evaluation of the following performance parameters: selectivity, linearity, precision, recovery, limits of detection, limits of quantification and ruggedness. The results indicated excellent selectivity, separation of all amines, a coefficient of determination greater than 0.99 and recovery from 92.25 to 102.25% at the concentration of 47.2mg.kg-1, with a limit of detection at 0.3mg.kg-1 and a limit of quantification at 0.9mg.kg-1 for all amines, with the exception of histamine, which exhibited the limit of quantification, of 1mg.kg-1. In conclusion, the performance parameters demonstrated adequacy of the method for the detection and quantification of bioactive amines in chicken meat.(AU)

Um método de cromatografia líquida de alta eficiência (CLAE) para pesquisa de aminas bioativas em carne de frango foi validado. Foi utilizado um sistema de gradiente de eluição com detector ultravioleta, após extração com ácido tricloroacético e derivação pré-coluna com cloreto de dansila. Os padrões de putrescina, cadaverina, histamina, tiramina, espermidina e espermina foram utilizados para avaliação dos seguintes parâmetros de desempenho: seletividade, linearidade, precisão, recuperação, limites de detecção, limites de quantificação e robustez. Os resultados mostraram excelente seletividade e separação de todas as aminas, coeficiente de determinação superior a 0,99, recuperação entre 92,25 e 105,25% na concentração 47,2mg.kg-1, limites de detecção de 0,3mg.kg-1 e limite de quantificação de 0,9mg.kg-1 para todas as aminas, com exceção da histamina, que apresentou o limite de quantificação mais alto, de 1mg.kg-1. Foi concluído que os parâmetros de desempenho demonstraram adequação do método para detecção e quantificação de aminas bioativas em carne de frango.(AU)

Avaliação da qualidade interna de ovos de consumo pela pesquisa do teor de aminas bioativas / Evaluation of the internal quality of commercial eggs by searching of the bioactive levels

Com o objetivo de avaliar a qualidade dos ovos de consumo pela pesquisa dos níveis de aminas bioativas, foram coletados, pelos serviços de inspeção oficiais, 224 amostras de ovos provenientes de cinco regiões distintas do estado de Minas Gerais, durante o período de um ano. As aminas biogênicas (putrescina, cadaverina, feniletilamina, histamina e tiramina) e as poliaminas (espermidina e espermina) foram pesquisadas por cromatografia líquida de alta eficiência e detecção ultravioleta (CLAE/UV) após derivação pré-coluna com cloreto de dansila. Os resultados demonstraram que a putrescina estava presente, em baixas concentrações, em todas as amostras de gema e de albúmen. As demais aminas também foram detectadas, porém em menor frequência, e a espermina somente foi encontrada em uma amostra de albúmen. Foi concluído que os ovos de consumo produzidos no estado de Minas Gerais não são uma fonte considerável de poliaminas, importantes para o crescimento e a proliferação celular, e os baixos teores de aminas biogênicas, formadas pela descarboxilação de aminoácidos por enzimas bacterianas, não representam riscos à saúde do consumidor, o que indica que o ovo apresenta boa qualidade, tomando por base o critério de aminas bioativas.

In order to evaluate the quality of commercial eggs by searching the bioactive amine levels, 224 samples of eggs from the five regions of Minas Gerais State were collected during one year by the official inspection service. The biogenic amines (putrescine, cadaverine, phenylethylamine, histamine and tyramine) and the polyamines (spermidine and spermine) were determined by high performance liquid chromatography with ultraviolet detection (HPLC/UV) and pre-column derivatization with dansyl chloride. The results demonstrated the presence of putrescine in all samples of yolk and albumen, but in low concentrations. The other amines were also detected, however, with a lower frequency, and spermine was found only in one sample of albumen. It was concluded that the commercial eggs produced in Minas Gerais State are not a considerable source of polyamines, important for growth and cell proliferation; and low levels of biogenic amine, formed by decarboxylation of amino acids by bacterial enzymes, do not represent risks to consumer health, indicating that it has good quality, based on the bioactive amine criterion.

Aminas bioativas e qualidade da carne de frangos de corte / Bioactive amines and meat quality of broiler chickens

Com o objetivo de avaliar a qualidade da carne de frangos de corte mediante pesquisa dos níveis de aminas bioativas, foram coletadas, pelos serviços de inspeção oficiais, 160 amostras de carcaças provenientes de cinco regiões distintas do estado de Minas Gerais, durante o período de um ano. As poliaminas (espermidina e espermina) e as aminas biogênicas (putrescina, cadaverina, histamina, tiramina) foram pesquisadas por cromatografia líquida de alta eficiência e detecção ultravioleta (CLAE/UV). Os resultados encontrados demonstraram a presença das poliaminas, espermidina e espermina, em todas as amostras, em concentrações médias de 3,56mg/100g e 5,72mg/100g, respectivamente. Em todas as amostras foram detectadas, em concentrações muito baixas, as aminas putrescina, cadaverina, histamina e tiramina. Foi concluído que a carne de frangos de corte produzida no estado de Minas Gerais é uma fonte de poliaminas, importantes para o crescimento e a proliferação celular, e que os baixos teores de aminas biogênicas encontrados não representam riscos à saúde do consumidor, indicando que esse tipo de carne apresenta boa qualidade, tomando por base o critério de aminas bioativas.

In order to evaluate the meat quality of broiler chickens by searching the bioactive amines level, 160 samples of carcass from the five regions of the Minas Gerais State, were collected during one year by the official inspection service. The poliamines (spermidine and spermine) and the biogenic amines (putrescine, cadaverine, histamine and tyramine) were determined by high performance liquid chromatography with ultraviolet detection (HPLC/UV). The results demonstrated the presence of polyamines spermidine and spermine in all samples, at mean concentrations of 3.56mg/100g and 5.72mg/100g, respectively. The biogenic amines putrescine, cadaverine, histamine and tyramine were also found, but in low concentrations. It was concluded that the chicken broiler meat produced in Minas Gerais state is a source of polyamines, important for growth and cell proliferation; and that the biogenic amine levels found were low, and do not represent risks to consumer health, indicating that it has good quality, based on the criterion of bioactive amine.

Effects of packaging, mineral oil coating, and storage time on biogenic amine levels and internal quality of eggs.

This study was carried out with the aim of evaluating the effects of mineral oil application on eggshells and the use of plastic packages with lids on the physical-chemical and microbiological quality and biogenic amine contents of eggs stored under refrigeration for up to 125 d. A total of 1,920 eggs from 46-wk-old Hyline W36 laying hens were randomly distributed into 4 groups soon after classification: (i) 480 eggs were stored in pulp carton tray packages; (ii) 480 eggs were stored in plastic packages with lids; (iii) 480 eggs were stored in carton packages after the application of mineral oil; and (iv) 480 eggs were stored in plastic packages with lids after the application of mineral oil. The internal quality was measured by Haugh units, by the counts of mesophilic and psychrotrophic microorganisms, by the most probable number of total and thermal-tolerant coliforms, by the counts of molds and yeasts, by the analysis of Salmonella spp. and Staphylococcus spp., and by the levels of biogenic amines in the egg yolk and albumen. The application of mineral oil to the eggshell resulted in higher Haugh unit values throughout storage, and the use of plastic packages altered the internal quality. The application of mineral oil and the use of packaging had no effects on the microbiological and biogenic amine results. Microbiological analyses showed the absence of Salmonella spp., Staphylococcus aureus, thermal-tolerant coliforms, and fungi. However, the highest counts of mesophilic (1.1 × 10(7) cfu/g) and psychrotrophic (6.7 × 10(7) cfu/g) microorganisms were recorded. The highest values of biogenic amines detected and quantified were putrescine (2.38 mg/kg) and cadaverine (7.27 mg/kg) in the egg yolk and putrescine (1.95 mg/kg), cadaverine (2.83 mg/kg), and phenylethylamine (2.57 mg/kg) in the albumen. Despite these results, the biogenic amine levels recorded were considered low and would not be harmful to consumer health.

Bioactive amines and microbiological quality in pasteurized and refrigerated liquid whole egg.

The objective of this study was to evaluate the correlation between the levels of bioactive amines and the microbiological quality of liquid pasteurized egg stored under refrigeration. Pasteurized whole egg liquid was obtained from 2 types of different raw materials, fresh eggs, and commercial fertile eggs. They were stored under refrigeration over a period of 21 d. The treatments were arranged in a completely randomized split plot, with the plots being the 2 types of liquid pasteurized egg, and the subplots being the 4 storage periods (1, 7, 14, and 21 d). The storage period did not contribute to the increase (P > 0.05) of contamination by mesophilic aerobic microorganisms and total coliforms in commercial liquid pasteurized egg. However, for fertile eggs, the storage period led to an increase (P < 0.05) in the numbers of microorganisms. Levels of the amines putrescine, cadaverine, and tyramine were detected only in fertile liquid pasteurized egg, and the storage period contributed to the increase (P < 0.05) in the levels of these amines. There was a high correlation between total coliform most probable number and cadaverine levels, and a moderate correlation between the numbers of aerobic mesophilic microorganisms and tyramine levels. It was concluded that the most contaminated liquid pasteurized eggs were the fertile liquid pasteurized eggs and this caused the highest levels of bioactive amines in them compared with all the eggs that had been subjected to pasteurization and refrigerated storage.

Influência do período de armazenamento na qualidade do ovo integral pasteurizado refrigerado / Influence of storage period on refrigerated pasteurized whole egg quality

Avaliaram-se o pH e a qualidade microbiológica de ovos integrais pasteurizados refrigerados obtidos de dois tipos de matéria-prima: o ovo in natura (comercial ) e o ovo galado (ovo fértil). Os tratamentos foram dispostos no delineamento inteiramente ao acaso, em parcelas subdivididas, sendo na parcela dois tipos de ovos integrais pasteurizados, o comercial e o galado, e na subparcela quatro períodos de estocagem sob temperatura de refrigeração, um, sete, 14 e 21 dias. Não foi observada a presença de Salmonella spp. em nenhuma amostra analisada, e para os ovos comerciais, o período de estocagem não contribuiu para o aumento (P>0,05) da contaminação por mesófilos aeróbios, coliformes a 35ºC, Staphylococcus spp. e bolores e leveduras. Para as amostras de ovos galados, o período de armazenamento influenciou no aumento (P<0,05) da contagem de mesófilos aeróbios, coliformes a 35ºC, bolores e leveduras, e Staphylococcus spp. Os valores de pH aumentaram durante os primeiros dias do armazenamento e depois voltaram a diminuir. Concluiu-se que os ovos integrais galados pasteurizados apresentam pior qualidade em relação aos ovos integrais comerciais pasteurizados, e que o período de validade sob refrigeração desses tipos de ovos poderia ser de sete e 14 dias, respectivamente.

The pH and microbiological quality of refrigerated pasteurized whole eggs at 4ºC obtained from two types of raw materials, in nature (commercial) egg and the fertile egg were evaluated. The treatments were arranged in a completely randomized split plot design, the two types of pasteurized whole eggs (commercial and fertile) were alloted to the plots and four periods of storage under refrigeration (one, seven, 14 and 21 days) to the split plot. The presence of Salmonella spp. was not observed in the samples and the commercial pasteurized whole egg storage period did not contribute to the increase (P>0.05) in mesophilic aerobic coliforms at 35ºC, Staphylococcus spp and mold and yeast contamination. For samples of fertile pasteurized whole eggs, the storage period influenced the increased (P<0.05) count of mesophilic aerobic, coliforms at 35ºC, mold and yeast and Staphylococcus spp. The pH values rose during the first days of storage and then decreased again. It was concluded that fertile pasteurized whole eggs have lower quality than the commercial pasteurized whole eggs, and that the shelf life of these could be seven and 14 days, respectively.

Viabilidade de Staphylococcus aureus FRI S-6 e produção de SEB em queijo elaborado com adição de Lactobacillus rhamnosus e Lactococcus lactis / Staphylococcus aureus FRI S-6 viability and its SEB production in cheese produced with Lactobacillus rhamnosus and Lactococcus lactis

Staphylococcus aureus foi inoculado em queijos produzidos de forma estéril em laboratório, juntamente com Lactobacillus rhamnosus e Lactococcus lactis, isolados de queijo de coalho artesanal e identificados por PCR-ARDRA16S-23S. L. lactis foi capaz de reduzir a contagem de S. aureus no primeiro dia após produção (P<0,05) dos queijos de 3,3x10(7)UFC/g para 1,0x10(7)UFC/g. L. rhamnosus não impediu o crescimento de S. aureus. A presença das cepas acidoláticas, principalmente L. lactis, mostrou ainda potencial de inibição da produção de enterotoxina estafilocócica do tipo B, sendo que a concentração de enterotoxinas no 15° dia foi inferior ao limite de detecção pelo kit comercial utilizado. Concluiu-se que a presença das bactérias acidoláticas estudadas pode contribuir para a melhoria da qualidade sanitária de queijos artesanais.

Staphylococcus aureus was inoculated in cheese elaborated with Lactobacillus rhamnosus and Lactococcus lactis, produced in a sterile lab, previously isolated from Brazilian coalho artisanal cheese and identified by PCR-ARDRA16S-23S. L. lactis was able to reduce the staphylococcal count on the first day after cheese production (P<0.05) from 3.33x10(7)CFU/g to 1.0x10(7)CFU/g. L. rhamnosus did not inhibit S. aureus growth. The presence of lactic acid bacteria (LAB), mainly L. lactis, also showed evidences of inhibition of the enterotoxin B production, and the staphylococcal enterotoxins concentration on the 15th day was lower than the commercial kit threshold. Hence, the studied LAB may contribute to the sanitary quality of artisanal cheeses.

Avaliação da qualidade microbiológica do soro de queijos Minas padrão e mozarela produzidos em quatro regiões do estado de Minas Gerais / Microbiological profile of the whey of nd mozzarella cheese produced in Minas Gerais state (Brazil)

The microbiological profile of whey from the queijo-de-minas (Minas padrão) and mozzarella type cheeses produced in four of five most important regions of Minas Gerais state was studied. The contamination percentage found is serious, mainly in terms of the result found in coliforms count at 45°C e coagulase-positive Staphylococci. The contamination of the whey would be too high, indicating the material as unsuitable for human consumption as well as for industrial means. Due to the lack of a specific identity and a quality pattern for cheese whey, the results can be taken as a base for standard developments, which are seen as necessary concerning the microbiological quality of such products.

Uso do probiótico "Paciflor" em dieta para coelhos em crescimento / The use of probiotic \"Paciflor\" in diet for growing rabbits

Com o objetivo de avaliar-se a eficácia nutricional do probiótico Paciflor R, cujo princípio ativo está constituído por esporos de Bacillus IP 5832, alojaram-se, individualmente, 60 coelhos de ambos os sexos, dos 30 dias de idade até alcançarem 2 quilos de peso vivo, alimentados "ad libitum" com duas dietas peletizadas e equitativamente equilibradas com 16 por centro de proteína bruta, 14 por cento de fibra bruta e 2500 kcal de energia digestível por quilo de dieta. Em uma das dietas foi incluído o probiótico na concentraçäo de 10 elevado à sexta potência esporos por grama. Ao final do período de crescimento, sacrificaram-se 44 coelhos dos dois grupos experimentais para avaliaçäo do rendimento de carcaça e dos pesos totais das vísceras e do ceco repletos de digestiva. Os resultados mostraram que a inclusäo do paciflor R näo alterou o período de crescimento (média = 48,4 dias) e o ganho de peso médio diário (média = 30,2 gramas), mas reduziu o consumo médio diário (102,1 vs 119,1 gramas) e a conversäo alimentar (3,5:1 vs 3,9:1). A mortalidade ocorrida no experimento näo foi associada ao tratamento com o probiótico. O rendimento de carcaça (média = 62,2 por cento) näo foi modificado, assim como as proporçöes dos pesos totais das vísceras e cecos repletos de digesta em relaçäo ao peso vivo (média = 16,4 por cento e 4,9 por cento respectivamente). Conclui-se que a inclusäo do probiótico Paciflor R em dietas compostas para coelhos em crescimento pode representar uma economia importante nos gastos com alimentaçäo sem, no entanto, induzir alteraçöes no ganho de peso e rendimento de carcaça