RESUMO

Considering that plasmid conjugation is a major driver for the dissemination of antimicrobial resistance in bacteria, this study aimed to investigate the effects of residual concentrations of antimicrobial growth promoters (AGPs) in poultry litter on the frequencies of IncFII-FIB plasmid conjugation among Escherichia coli organisms. A 2 × 5 factorial trial was performed in vitro, using two types of litter materials (sugarcane bagasse and wood shavings) and five treatments of litter: non-treated (CON), herbal alkaloid sanguinarine (SANG), AGPs monensin (MON), lincomycin (LCM) and virginiamycin (VIR). E. coli H2332 and E. coli J62 were used as donor and recipient strains, respectively. The presence of residues of monensin, lincomycin and virginiamycin increased the frequency of plasmid conjugation among E. coli in both types of litter materials. On the contrary, sanguinarine significantly reduced the frequency of conjugation among E. coli in sugarcane bagasse litter. The conjugation frequencies were significantly higher in wood shavings compared with sugarcane bagasse only in the presence of AGPs. Considering that the presence of AGPs in the litter can increase the conjugation of IncFII-FIB plasmids carrying antimicrobial resistance genes, the real impact of this phenomenon on the dissemination of antimicrobial resistant bacteria in the poultry production chain must be investigated.

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RESUMO

The objective is to evaluate different bedding materials, including dehydrated grass, on performance and carcass yield and verify the physicochemical and microbiological characteristics of materials. The completely randomized experiment comprised 1,080 chicks in a 3 × 2 factorial design with three levels of dehydrated grass (0%, 25%, and 50%) and two bedding materials (rice husks and shavings). Total microorganism count and physicochemical characteristics, surface temperature of birds, and performance of birds were analyzed up to 42 days of age, when birds were slaughtered, and carcass yield was evaluated. The inclusion of grass showed a higher microbiological count after 1 day, stabilizing with materials after 28 days. The inclusion of 50% of dehydrated grass resulted in a higher surface bed temperature at 42 days. Inclusions above 25% of grass have a lower density and a greater water retention capacity, pH, moisture, and total nitrogen, in addition to a lower FDA in its structure. The highest ammonia emissions occurred with the inclusion of 25% of grass. The inclusion of dehydrated grass did not affect performance and carcass yield, favoring feed conversion at the initial stages. The inclusion of grass can replace up to 25% of shavings without harming physicochemical parameters of materials and birds' performance.

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ABSTRACT This study aimed to evaluate the efficacy of biofilms formed by lactic acid bacteria and Bacillus sp. (BLA) in preventing and controlling the formation of wild biofilms and/or planktonic forms of Salmonella Gallinarum (SG), Salmonella Heidelberg (SH), and methicillin-resistant Staphylococcus aureus (MRSA) on different surfaces. The SH and SG viability was evaluated in polystyrene plates, wood shavings, and soil samples. Two protocols were developed to examine the use of BLA in a preventive and control application. For analysis of Campylobacter jejuni (CJ) BLA was used only preventively in a polystyrene plate. Results showed that BLA was effective in preventing the growth of SG and SH in all matrices. The effectiveness of BLA for MRSA was lower than for SG and SH. The efficiency of BLA in preventing CJ growth seems to be related to the initial CJ contamination. BLA proves to be a potential alternative to control food-borne pathogens commonly encountered in animal production and food industry.

RESUMO

As afecções do sistema respiratório são a segunda causa de queda de desempenho e afastamento dos equinos do esporte ou trabalho, as quais estão atrás somente das desordens musculoesqueléticas. A estabulação e a alimentação à base de fenos predispõem os equinos à inalação de grande número de agentes irritantes às vias aéreas. No intuito de avaliar a influência dos tipos de cama utilizados em baias, estudaram-se três grupos de cinco equinos cada, durante 45 dias. Dois grupos foram mantidos em cocheiras com forrações diferentes à base de madeira (maravalha de pínus autoclavada-MA e serragem-SE) e o terceiro grupo permaneceu no pasto. Foram realizadas avaliações quinzenais, que incluíram exame físico, hemograma, hemogasometria e lavado broncoalveolar. Ao exame físico, notou-se a presença de tosse e espirros em animais do grupo SE. No lavado broncoalveolar, a contagem de células nucleadas totais apresentou maiores valores nos animais a pasto, seguido do grupo SE e, por último, o MA. Concluiu-se que as duas camas testadas neste estudo não apresentaram diferença com relação à capacidade irritativa das vias aéreas superiores no período analisado.(AU)

Respiratory system affections in horses are the second cause of decrease in performance and removal from the sport or farm work, which are behind only the musculoskeletal disorders. Stabling and hay feeding predisposes horses' airways to inhalation of large numbers of irritating agents. To evaluate the influence of bed types used in bays, 3 groups of 5 horses each were studied for 45 days. Two groups were kept in stables with different wood beds - based rafters (autoclaved pine - MA and sawdust - SE) and the third group remained in the pasture. Biweekly evaluations with physical examination, hemogram, hemogasometry and bronchoalveolar lavage were performed. On physical examination, the presence of cough and sneezing was observed in animals of the SE group. In the bronchoalveolar lavage, the total nucleated cell count presented higher values in the animals in the pasture, followed by the SE group and finally the MA. It was concluded that the different beds used presented no difference with respect to the irritative capacity of the upper airways.(AU)

Assuntos

RESUMO

As afecções do sistema respiratório são a segunda causa de queda de desempenho e afastamento dos equinos do esporte ou trabalho, as quais estão atrás somente das desordens musculoesqueléticas. A estabulação e a alimentação à base de fenos predispõem os equinos à inalação de grande número de agentes irritantes às vias aéreas. No intuito de avaliar a influência dos tipos de cama utilizados em baias, estudaram-se três grupos de cinco equinos cada, durante 45 dias. Dois grupos foram mantidos em cocheiras com forrações diferentes à base de madeira (maravalha de pínus autoclavada-MA e serragem-SE) e o terceiro grupo permaneceu no pasto. Foram realizadas avaliações quinzenais, que incluíram exame físico, hemograma, hemogasometria e lavado broncoalveolar. Ao exame físico, notou-se a presença de tosse e espirros em animais do grupo SE. No lavado broncoalveolar, a contagem de células nucleadas totais apresentou maiores valores nos animais a pasto, seguido do grupo SE e, por último, o MA. Concluiu-se que as duas camas testadas neste estudo não apresentaram diferença com relação à capacidade irritativa das vias aéreas superiores no período analisado.(AU)

Respiratory system affections in horses are the second cause of decrease in performance and removal from the sport or farm work, which are behind only the musculoskeletal disorders. Stabling and hay feeding predisposes horses' airways to inhalation of large numbers of irritating agents. To evaluate the influence of bed types used in bays, 3 groups of 5 horses each were studied for 45 days. Two groups were kept in stables with different wood beds - based rafters (autoclaved pine - MA and sawdust - SE) and the third group remained in the pasture. Biweekly evaluations with physical examination, hemogram, hemogasometry and bronchoalveolar lavage were performed. On physical examination, the presence of cough and sneezing was observed in animals of the SE group. In the bronchoalveolar lavage, the total nucleated cell count presented higher values in the animals in the pasture, followed by the SE group and finally the MA. It was concluded that the different beds used presented no difference with respect to the irritative capacity of the upper airways.(AU)

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RESUMO

1. Divergence in outcomes from studies on the effects of litter materials on body weight, feed intake, feed conversion and mortality in broilers has led to a need for a meta-analysis to quantify their effects.2. A systematic search of published quantitative research relating to wood shavings and alternative bedding litters was conducted using databases.3. Means, standard deviations and sample sizes were extracted from each study. The response variables were analysed using the standardised mean difference (SMD, control treatment minus alternative litters).4. The literature demonstrated that alternative materials have no impact on feed intake in broilers, compared to wood shavings (SMD = 0.064, 95% CI = -0.101-0.229, P = 0.44).5. There was a positive overall effect of wood shavings on body weight (SMD = 0.253, 95% CI = 0.073-0.433, P = 0.006), feed conversion (SMD = -0.169, 95% CI = -0.327 - -0.012, P = 0.03) and mortality (SMD = -1.069, 95% CI = -1.983 - -0.155, P = 0.02) of broilers, compared to other litter types.6. Subgroup meta-analysis revealed that straw, when used as an alternative litter material to wood shavings, may be responsible for lower body weight (SMD = 0.654, 95% CI = 0.162-1.146, P = 0.009), worse feed conversion (SMD = -0.487, 95% CI = -0.828 - -0.145, P = 0.005) and higher mortality rates of broilers (SMD = -3.25, 95% CI = -5.681 - -0.819, P = 0.009). Rice husks impaired body weight compared to wood shavings (SMD = 0.535, 95% CI = 0.065-1.004, P = 0.02).7. It was concluded that different litter types do not affect the broilers' feed intake. Conversely, broilers kept on straw showed lower body weights, worse feed conversion and higher mortality rates, in comparison to wood shavings. Rice husks decreased body weight compared to wood shavings.

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Recent catastrophes that occurred during seismic events suggest the importance of developing new seismic-resistant materials for use in building construction. Ordinary concrete is one of the most common materials in buildings. However, due to its low ductility and flexural strength, its seismic behavior can be improved upon by different additives. In this regard, wood-concrete composites exhibit desirable structural properties not achievable by either wood or concrete alone, making it an interesting material from a seismic point of view. This work analyzes and compares the performance of blocks built with ordinary concrete versus blocks built using different wood additives (sawdust and wood shavings). This includes the construction of concrete blocks in a lab, determination of their construction and seismic-resistant properties, as well as an analysis of their performance in buildings with a different number of storeys. The results show how blocks with wood aggregates comply with current regulations for structural materials in a seismic country like Chile, while also considerably outperforming traditional concrete blocks in the event of an earthquake.

RESUMO

Recentemente, os programas de enriquecimento ambiental em biotérios têm sido amplamente discutidos. Muitos estudos, ao longo dos anos, procuraram esclarecer se as diferentes estratégias de enriquecimento ambiental (EA) podem afetar o comportamento e a fisiologia de roedores de laboratório, sendo que a maioria dos autores reconheceu o efeito positivo do EA para a melhora da qualidade de vida dos animais utilizados na experimentação. Neste trabalho foram realizados dois experimentos com o objetivo de avaliar o impacto do EA e do tipo de cama no desempenho reprodutivo e no comportamento maternal de ratas Wistar, bem como no desenvolvimento físico de sua prole. Para isto as ratas foram distribuídas em três grupos: EA-S (enriquecido com cama de sabugo de milho), EA-M (enriquecido com cama de maravalha) e NE-M (não enriquecido com cama de maravalha). Os resultados demonstraram que não houve diferença no intervalo entre partos, número de filhotes nascidos e desmamados nos três grupos avaliados, sendo que esses dados foram semelhantes aos descritos na literatura para ratos Wistar. Também não foi observada diferença estatística no comportamento maternal; no entanto no desenvolvimento físico observou-se antecipação no desdobramento das orelhas, erupção dos dentes incisivos e descida dos testículos dos filhotes do grupo EA-S; além do que as ratas dos grupos expostos ao EA confeccionaram ninhos mais íntegros e de melhor qualidade. Esses resultados reforçam a importância de se fornecer EA, como material de ninho, para que as mães criem seu próprio microambiente, e assim, possam oferecer melhor conforto e bem-estar aos seus filhotes.

Recently, environmental enrichment (EA) programs in laboratory animal facilities have been widely discussed. Many studies over the years have sought to clarify whether different environmental enrichment strategies may affect the behavior and physiology of laboratory rodents, in which most authors recognized the positive effect of EA for the life of animals used in research. In the present work two experiments were carried out to evaluate the impact of EA and bedding material on the reproductive performance and maternal behavior of Wistar rats, as well as the physical development of their offspring. For this, the rats were divided into three groups: EA-S (enriched with corn cobs bedding), EA-M (enriched with wood shavings bedding) and NE-M (not enriched with wood shavings bedding). The results showed that there was no difference in the interval between births, and number of pups born and weaned of the three groups evaluated, being these data similar to those described in the literature for Wistar rats. There was also no statistical difference in the maternal behavior; however in the physical development we observed anticipation of pinnae detachment, incisor teeth eruption and testicles descent of the EA-S group pups; in addition the female rats of the groups exposed to EA made more intact nests with better quality. These results reinforce the importance of providing EA, such as nest material, for mothers to create their own microenvironment, thus providing better comfort and well-being for their offspring.

Assuntos

RESUMO

Recentemente, os programas de enriquecimento ambiental em biotérios têm sido amplamente discutidos. Muitos estudos, ao longo dos anos, procuraram esclarecer se as diferentes estratégias de enriquecimento ambiental (EA) podem afetar o comportamento e a fisiologia de roedores de laboratório, sendo que a maioria dos autores reconheceu o efeito positivo do EA para a melhora da qualidade de vida dos animais utilizados na experimentação. Neste trabalho foram realizados dois experimentos com o objetivo de avaliar o impacto do EA e do tipo de cama no desempenho reprodutivo e no comportamento maternal de ratas Wistar, bem como no desenvolvimento físico de sua prole. Para isto as ratas foram distribuídas em três grupos: EA-S (enriquecido com cama de sabugo de milho), EA-M (enriquecido com cama de maravalha) e NE-M (não enriquecido com cama de maravalha). Os resultados demonstraram que não houve diferença no intervalo entre partos, número de filhotes nascidos e desmamados nos três grupos avaliados, sendo que esses dados foram semelhantes aos descritos na literatura para ratos Wistar. Também não foi observada diferença estatística no comportamento maternal; no entanto no desenvolvimento físico observou-se antecipação no desdobramento das orelhas, erupção dos dentes incisivos e descida dos testículos dos filhotes do grupo EA-S; além do que as ratas dos grupos expostos ao EA confeccionaram ninhos mais íntegros e de melhor qualidade. Esses resultados reforçam a importância de se fornecer EA, como material de ninho, para que as mães criem seu próprio microambiente, e assim, possam oferecer melhor conforto e bem-estar aos seus filhotes.(AU)

Recently, environmental enrichment (EA) programs in laboratory animal facilities have been widely discussed. Many studies over the years have sought to clarify whether different environmental enrichment strategies may affect the behavior and physiology of laboratory rodents, in which most authors recognized the positive effect of EA for the life of animals used in research. In the present work two experiments were carried out to evaluate the impact of EA and bedding material on the reproductive performance and maternal behavior of Wistar rats, as well as the physical development of their offspring. For this, the rats were divided into three groups: EA-S (enriched with corn cobs bedding), EA-M (enriched with wood shavings bedding) and NE-M (not enriched with wood shavings bedding). The results showed that there was no difference in the interval between births, and number of pups born and weaned of the three groups evaluated, being these data similar to those described in the literature for Wistar rats. There was also no statistical difference in the maternal behavior; however in the physical development we observed anticipation of pinnae detachment, incisor teeth eruption and testicles descent of the EA-S group pups; in addition the female rats of the groups exposed to EA made more intact nests with better quality. These results reinforce the importance of providing EA, such as nest material, for mothers to create their own microenvironment, thus providing better comfort and well-being for their offspring.(AU)

Assuntos

RESUMO

No sistema de criação em piso as galinhas são criadas diretamente em contato com o chão que pode ser coberto por diferentes tipos de materiais. Objetivou-se avaliar o ambiente térmico, o comportamento, os índices zootécnicos e a qualidade de ovos de galinhas poedeiras criadas em dois tipos de piso, maravalha e grama sintética. Foram utilizadas 120 galinhas da linhagem Hisex Brown®, destas, metade foi criada sobre maravalha e a outra metade sobre grama sintética (Tapete Astro Turf®) distribuídas em um delineamento inteiramente casualizado em medidas repetidas no tempo, com dois tratamentos e duas repetições com 30 galinhas por unidade experimental durante 56 dias. Avaliou-se as temperaturas máxima e mínima, bulbo seco, bulbo úmido e de globo negro, umidade relativa, índice de temperatura e umidade e índice de temperatura de globo negro e umidade; a frequência do comportamento natural; produção de ovos por ave/dia, por ave alojada, ovos comercializáveis, viabilidade, consumo de ração, conversão alimentar por dúzia e por massa e qualidade física dos ovos. Os dados foram analisados por meio da análise de variância e as médias comparadas pelo teste F, a 0,05 de probabilidade, exceto a frequência do comportamento que foi analisada pelo teste Qui- quadrado. Os índices zootécnicos das aves foram coerentes com as recomendações dos manuais da linhagem. Apenas foi observada diferença significativa para a melhor conversão alimentar por massa das aves criadas sob grama sintética. Desta forma, verifica-se que a grama sintética pode ser um excelente substrato para a cama de galinhas semipesadas na fase de produção.(AU)

In the system of creation in floor the hens are created directly in contact with the floor that can be covered by different types of materials. The aim of this study was to evaluate the thermal environment, behavior, zootechnical indexes and quality of chicken eggs created in two types of flooring, wooden shavings and synthetic grass, were used 120 semi-heavy laying hens, Hysex Brown®, of these, half were created on wooden shaving and half on synthetic grass (Carpet Astro Turf®) distributed in a completely randomized in repeated measures in time in two treatments and two replications of 30 laying hens, during 56 days (two periods of 28 days). Were evaluated temperatures maximum and minimum, dry and wet bulb temperature, black globe temperature, relative humidity, temperature and humidity index and black globe temperature and humidity index; the frequency of natural behavior; the daily egg production per bird, per bird housed, and marketable, viability, feed consumption and feed conversion per dozen and per mass, average egg weight, specific weight and egg shell thickness. Data were analyzed using analysis of variance and means compared by F test at 0.05 probability, except the frequency of natural behavior that was analyzed using the chi square analysis test. The results show that the values of the zootechnical indexes of the layers are consistent with the guide strains recommendations, having no influence from the kind of floor used as bed. Only significant differences were observed in the feed intakeper mass of birds grown under synthetic grass. Thus, it seems that synthetic grass could be an excellent substrate for the bed of semi-heavy laying hens in the egg production phase.(AU)

Assuntos

RESUMO

No sistema de criação em piso as galinhas são criadas diretamente em contato com o chão que pode ser coberto por diferentes tipos de materiais. Objetivou-se avaliar o ambiente térmico, o comportamento, os índices zootécnicos e a qualidade de ovos de galinhas poedeiras criadas em dois tipos de piso, maravalha e grama sintética. Foram utilizadas 120 galinhas da linhagem Hisex Brown®, destas, metade foi criada sobre maravalha e a outra metade sobre grama sintética (Tapete Astro Turf®) distribuídas em um delineamento inteiramente casualizado em medidas repetidas no tempo, com dois tratamentos e duas repetições com 30 galinhas por unidade experimental durante 56 dias. Avaliou-se as temperaturas máxima e mínima, bulbo seco, bulbo úmido e de globo negro, umidade relativa, índice de temperatura e umidade e índice de temperatura de globo negro e umidade; a frequência do comportamento natural; produção de ovos por ave/dia, por ave alojada, ovos comercializáveis, viabilidade, consumo de ração, conversão alimentar por dúzia e por massa e qualidade física dos ovos. Os dados foram analisados por meio da análise de variância e as médias comparadas pelo teste F, a 0,05 de probabilidade, exceto a frequência do comportamento que foi analisada pelo teste Qui- quadrado. Os índices zootécnicos das aves foram coerentes com as recomendações dos manuais da linhagem. Apenas foi observada diferença significativa para a melhor conversão alimentar por massa das aves criadas sob grama sintética. Desta forma, verifica-se que a grama sintética pode ser um excelente substrato para a cama de galinhas semipesadas na fase de produção.

In the system of creation in floor the hens are created directly in contact with the floor that can be covered by different types of materials. The aim of this study was to evaluate the thermal environment, behavior, zootechnical indexes and quality of chicken eggs created in two types of flooring, wooden shavings and synthetic grass, were used 120 semi-heavy laying hens, Hysex Brown®, of these, half were created on wooden shaving and half on synthetic grass (Carpet Astro Turf®) distributed in a completely randomized in repeated measures in time in two treatments and two replications of 30 laying hens, during 56 days (two periods of 28 days). Were evaluated temperatures maximum and minimum, dry and wet bulb temperature, black globe temperature, relative humidity, temperature and humidity index and black globe temperature and humidity index; the frequency of natural behavior; the daily egg production per bird, per bird housed, and marketable, viability, feed consumption and feed conversion per dozen and per mass, average egg weight, specific weight and egg shell thickness. Data were analyzed using analysis of variance and means compared by F test at 0.05 probability, except the frequency of natural behavior that was analyzed using the chi square analysis test. The results show that the values of the zootechnical indexes of the layers are consistent with the guide strains recommendations, having no influence from the kind of floor used as bed. Only significant differences were observed in the feed intakeper mass of birds grown under synthetic grass. Thus, it seems that synthetic grass could be an excellent substrate for the bed of semi-heavy laying hens in the egg production phase.

Assuntos

RESUMO

his experiment was carried out in a 104 m2 poultry house located between the geographical coordinates 25°45'00" south latitude and 53°03'25" west longitude and an average altitude of 550 m, from September to November, 2008. The chickens were placed in 12 pens measuring 2 m2 each at a stocking density of 12 chickens m-2. This study aimed at evaluating the effect of two different initial weights (chick weight on first day of experiment) and two types of litter material on broiler production parameters, litter humidity, as well as on breast and footpad lesions. A total of 240 female Cobb® chickens, derived from the same flock of breeders, was distributed in a completely randomized experimental design with a 2 (initial weight) by 2 (litter material) factorial arrangement with three replicates per treatment. Initial weights were classified as light (34.40 - 35.22 g) or heavy (39.29 - 41.30 g), whereas wood shavings and sawdust were used as litter material. Data were analyzed by ANOVA and means were compared by Tukey's test at 95% confidence level. Initial weight significantly influenced bird performance, as chickens with heavy initial weight presented higher feed intake and body weight. Type of litter did not have any effect on breast injuries and litter humidity. However, the wood shavings litter significantly influenced footpad lesions.

Assuntos

RESUMO

his experiment was carried out in a 104 m2 poultry house located between the geographical coordinates 25°45'00" south latitude and 53°03'25" west longitude and an average altitude of 550 m, from September to November, 2008. The chickens were placed in 12 pens measuring 2 m2 each at a stocking density of 12 chickens m-2. This study aimed at evaluating the effect of two different initial weights (chick weight on first day of experiment) and two types of litter material on broiler production parameters, litter humidity, as well as on breast and footpad lesions. A total of 240 female Cobb® chickens, derived from the same flock of breeders, was distributed in a completely randomized experimental design with a 2 (initial weight) by 2 (litter material) factorial arrangement with three replicates per treatment. Initial weights were classified as light (34.40 - 35.22 g) or heavy (39.29 - 41.30 g), whereas wood shavings and sawdust were used as litter material. Data were analyzed by ANOVA and means were compared by Tukey's test at 95% confidence level. Initial weight significantly influenced bird performance, as chickens with heavy initial weight presented higher feed intake and body weight. Type of litter did not have any effect on breast injuries and litter humidity. However, the wood shavings litter significantly influenced footpad lesions.(AU)

Assuntos

RESUMO

This experiment was carried out in a 104 m² poultry house located between the geographical coordinates 25°45'00" south latitude and 53°03'25" west longitude and an average altitude of 550 m, from September to November, 2008. The chickens were placed in 12 pens measuring 2 m² each at a stocking density of 12 chickens m-2. This study aimed at evaluating the effect of two different initial weights (chick weight on first day of experiment) and two types of litter material on broiler production parameters, litter humidity, as well as on breast and footpad lesions. A total of 240 female Cobb® chickens, derived from the same flock of breeders, was distributed in a completely randomized experimental design with a 2 (initial weight) by 2 (litter material) factorial arrangement with three replicates per treatment. Initial weights were classified as light (34.40 - 35.22 g) or heavy (39.29 - 41.30 g), whereas wood shavings and sawdust were used as litter material. Data were analyzed by ANOVA and means were compared by Tukey's test at 95% confidence level. Initial weight significantly influenced bird performance, as chickens with heavy initial weight presented higher feed intake and body weight. Type of litter did not have any effect on breast injuries and litter humidity. However, the wood shavings litter significantly influenced footpad lesions.