RESUMO

The objective of this study was to evaluate the effectiveness of a litter conditioning compound (LCC) based on 98% phyllosilicates (kaolinite) and 2% cinnamon essential oil to be applied on the litter of broiler houses. Animal performance, prevalence of footpad lesions, and litter quality (water activity, pH, and moisture) were evaluated, in addition to the effect on the incidence of Salmonella spp., evaluated by testing shoe-drag swabs, fecal samples, and organs. Twenty-one broiler houses with similar structure and rearing conditions were distributed in a completely randomized design with three treatments and seven replications each, as follows: T0: control, without the use of LCC; T100: application of 100 grams of LCC per m² of litter per week; T200: application of 200 grams of LCC per m² of litter per week. There was no significant effect of treatments on performance variables; however litter pH was lower when 200g/m2 was used in comparison with the control treatment, a result not verified for moisture and water activity (p>0.05). Our findings demonstrated significant reduction in the percentage of footpad lesions in birds that received the LCC (T0: 63.37%; T100: 41.38% and T200: 27.24%). A reduction in the number of positive flocks for Salmonella spp. Was also observed (with overall positivity rates of 17.86%, 12.14%, and 5% for treatments T0, T100, and T200, respectively). It is concluded that the product reduces the incidence of Salmonella spp. and also significantly reduces the incidence of footpad lesions, two important factors for the poultry industry.(AU)

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RESUMO

Brazil is the largest exporter of chicken meat and poultry farming is one of the most important productive segments, despite major losses due to the bacterium Escherichia coli, which is also a zoonotic microorganism. The objetive of this study was to isolate E. coli and to evaluate its transmissibility potential from the field to chicken meat using the Pulsed Field Gel Electrophoresis (PFGE) technique. Environmental samples (poultry litter, soil and water) were collected from broiler farms located in the South of Brazil where the majority of the Brazilian poultry production occurs. In addition, chicken meat (gizzard, heart, drumette and tulip) samples were collected from local supermarkets. As results, 47.36% of the samples were positives for E. coli. Furthermore, 10 pairs of clones of E. coli were found always in the same substrate (two water-water pairs; three soil-soil pairs and five meat-meat pairs) using PFGE. These findings suggest that certain strains of E. coli may have habitat preferences, making the transfer from one substrate type to another more difficult to occur. Moreover, since no clones were found between environmental samples and chicken meat, it is possible to imply a low risk of E. coli transmissibility throughout the chicken meat production chain.(AU)

Assuntos

RESUMO

Brazil is the largest exporter of chicken meat and poultry farming is one of the most important productive segments, despite major losses due to the bacterium Escherichia coli, which is also a zoonotic microorganism. The objetive of this study was to isolate E. coli and to evaluate its transmissibility potential from the field to chicken meat using the Pulsed Field Gel Electrophoresis (PFGE) technique. Environmental samples (poultry litter, soil and water) were collected from broiler farms located in the South of Brazil where the majority of the Brazilian poultry production occurs. In addition, chicken meat (gizzard, heart, drumette and tulip) samples were collected from local supermarkets. As results, 47.36% of the samples were positives for E. coli. Furthermore, 10 pairs of clones of E. coli were found always in the same substrate (two water-water pairs; three soil-soil pairs and five meat-meat pairs) using PFGE. These findings suggest that certain strains of E. coli may have habitat preferences, making the transfer from one substrate type to another more difficult to occur. Moreover, since no clones were found between environmental samples and chicken meat, it is possible to imply a low risk of E. coli transmissibility throughout the chicken meat production chain.

Assuntos

RESUMO

Many important studies on resistance reversion, anthelmintic efficacy and, especially, new molecules with antiparasitic effects are performed in laboratories using gerbils (Meriones unguiculatus) as the experimental model. This study aimed to evaluate the use of corticosteroids (dexamethasone and methylprednisolone acetate) in gerbils experimentally infected with different doses of infective larvae (sheathed or exsheathed) of Haemonchus contortus. In the first experiment, 28 gerbils were divided into seven groups infected by 2-6 × 103 larvae, with or without immunosuppression using corticosteroids. In the second experiment, eight gerbils were divided into two groups infected by 2 × 103 sheathed or exsheathed larvae. For the third assay, seven immunosuppressed gerbils were infected with 2 × 103 sheathed larvae and were killed 15 days post infection (PI). The highest number of parasites was recovered from methylprednisolone-immunosuppressed animals. We observed red and white blood cell alterations and biochemical parameters in infected animals that had undergone immunosuppression with methylprednisolone. We highlight that in the first and second experiments a satisfactory number of worms was recovered using sheathed larvae and immunocompetent animals. When exsheathed larvae were used, the number of worms recovered was unsatisfactory. A considerable larval burden was recovered from immunosuppressed gerbils 15 days PI, and body weight did not influence establishment of larvae.

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RESUMO

The objective of this study was to evaluate the quality of cow milk from the West region of Santa Catarina State from 2009 to 2010 regarding total bacterial count (TBC), somatic cell count (SCC) and some physicochemical parameters according to the requirements of the Brazilian legislation (Normative Instruction No. 62/2011, MAPA). The quality parameters evaluated were fat, protein, lactose, non-fat solids, cryoscopic index, total bacterial count (TBC) and somatic cell count (SCC). The results indicated variations between years regarding protein, lactose and non-fat solids remaining higher in most of 2010, which was not observed for the cryoscopic index. The TBC was above the maximum allowed by the Brazilian legislation on the entire evaluated period, with higher values in the Autumn of both evaluated years. The SCC was high and above the standard in most of the time during 2010. In addition, relative variations were observed in the seasonal periods, with peaks in SCC in the summer of 2009 and 2010. The observed increase on physicochemical levels between the years of 2009 and 2010 might be related to the payment of bonus for milk quality, which has been widely applied by the dairy industry to farmers in the region. High SCC and TBC indicate herd health issues and poor hygienic measures during milking and handling of the milk, which could affect the milk and its derivatives quality.

Objetivou-se avaliar a qualidade do leite da região Oeste de Santa Catarina através da contagem bacteriana total, contagem de células somáticas e da quantifi cação de parâmetros físico-químicos relacionados com as exigências da legislação brasileira (MAPA - Instrução Normativa nº 62/2011), ao longo dos anos de 2009 e 2010. Os parâmetros de qualidade avaliados foram gordura, proteína, lactose, sólidos não gordurosos, índice crioscópico, contagem bacteriana total (CBT) e contagem de células somáticas (CCS). Os resultados indicaram variações entre os anos, sendo que os teores de proteína, lactose e sólidos não gordurosos mantiveram-se superiores na maior parte de 2010, ao contrário do observado para o índice crioscópico. A CBT ficou acima do valor máximo permitido pela legislação em todo o período avaliado, com valores mais elevados no outono de ambos os anos avaliados. A CCS foi elevada e acima do padrão, na maioria dos meses de 2010. Além disso, foram observadas variações relativas nos períodos sazonais, com picos na CCS no verão de 2009 e 2010. O aumento observado nos níveis físico-químicos entre os anos de 2009 e 2010 pode estar relacionado ao pagamento de bônus pela qualidade do leite, que tem sido amplamente aplicado pela indústria laticinista para os produtores da região. Altas CCS e CBT indicam problemas na saúde dos rebanhos e de higiene no manejo e na ordenha, além de interferir na qualidade do leite e dos produtos lácteos.

Assuntos

RESUMO

The objective of this study was to evaluate the quality of cow milk from the West region of Santa Catarina State from 2009 to 2010 regarding total bacterial count (TBC), somatic cell count (SCC) and some physicochemical parameters according to the requirements of the Brazilian legislation (Normative Instruction No. 62/2011, MAPA). The quality parameters evaluated were fat, protein, lactose, non-fat solids, cryoscopic index, total bacterial count (TBC) and somatic cell count (SCC). The results indicated variations between years regarding protein, lactose and non-fat solids remaining higher in most of 2010, which was not observed for the cryoscopic index. The TBC was above the maximum allowed by the Brazilian legislation on the entire evaluated period, with higher values in the Autumn of both evaluated years. The SCC was high and above the standard in most of the time during 2010. In addition, relative variations were observed in the seasonal periods, with peaks in SCC in the summer of 2009 and 2010. The observed increase on physicochemical levels between the years of 2009 and 2010 might be related to the payment of bonus for milk quality, which has been widely applied by the dairy industry to farmers in the region. High SCC and TBC indicate herd health issues and poor hygienic measures during milking and handling of the milk, which could affect the milk and its derivatives quality.(AU)

Objetivou-se avaliar a qualidade do leite da região Oeste de Santa Catarina através da contagem bacteriana total, contagem de células somáticas e da quantifi cação de parâmetros físico-químicos relacionados com as exigências da legislação brasileira (MAPA - Instrução Normativa nº 62/2011), ao longo dos anos de 2009 e 2010. Os parâmetros de qualidade avaliados foram gordura, proteína, lactose, sólidos não gordurosos, índice crioscópico, contagem bacteriana total (CBT) e contagem de células somáticas (CCS). Os resultados indicaram variações entre os anos, sendo que os teores de proteína, lactose e sólidos não gordurosos mantiveram-se superiores na maior parte de 2010, ao contrário do observado para o índice crioscópico. A CBT ficou acima do valor máximo permitido pela legislação em todo o período avaliado, com valores mais elevados no outono de ambos os anos avaliados. A CCS foi elevada e acima do padrão, na maioria dos meses de 2010. Além disso, foram observadas variações relativas nos períodos sazonais, com picos na CCS no verão de 2009 e 2010. O aumento observado nos níveis físico-químicos entre os anos de 2009 e 2010 pode estar relacionado ao pagamento de bônus pela qualidade do leite, que tem sido amplamente aplicado pela indústria laticinista para os produtores da região. Altas CCS e CBT indicam problemas na saúde dos rebanhos e de higiene no manejo e na ordenha, além de interferir na qualidade do leite e dos produtos lácteos.(AU)

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RESUMO

The aim of this study was to evaluate anaemia, serum iron concentrations and δ-aminolevulinate dehydratase (ALA-D) activity in laying hens infected naturally by Salmonella Gallinarum and having severe hepatic lesions. Liver and serum samples were collected from 27 laying hens (20 infected and seven uninfected). The δ-ALA-D activity, haematocrit and serum iron concentrations were evaluated. There were significant decreases in δ-ALA-D activity, haematocrit and serum iron concentrations (P <0.01) in birds infected by S. Gallinarum when compared with uninfected birds. There was a positive correlation (P <0.001) between serum iron concentration, haematocrit (r(2) = 0.82) and δ-ALA-D activity (r(2) = 0.75). A positive correlation was also observed between δ-ALA-D activity and haematocrit (r(2) = 0.78; P <0.01). Liver samples showed moderate focal coagulative necrosis associated with infiltration of lymphoplasmacytic cells, macrophages and heterophils. The anaemia in the infected hens may be related to reduction in δ-ALA-D activity and serum iron concentrations, since both are important for haemopoiesis.

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RESUMO

The aim of this study was to evaluate the role of butyrylcholinesterase (BChE) (in the serum and pancreas), acetylcholinesterase (AChE) (in the whole blood and pancreas) and nitric oxide (NO) (in the serum and pancreas) in cattle infected naturally by Eurytrema coelomaticum. Fifty-one cattle were studied, including 33 infected by E. coelomaticum and 18 uninfected animals. Significantly greater AChE activity was found in the pancreas of infected animals (P <0.01); however, these cattle had lower AChE activity in whole blood. BChE activity was greater in the sera of infected animals (P = 0.05), but was less in pancreatic samples. NO levels were significantly higher in the sera (P <0.05) and pancreas (P <0.001) of infected cattle compared with uninfected animals. A positive correlation was found between AChE activity in the pancreas and parasite load, but there was negative correlation between pancreatic BChE activity and parasitic load. Expression of AChE, BChE and NO is therefore linked to the inflammation caused by E. coelomaticum in cattle.

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RESUMO

The aim of this study was to evaluate the in vitro bioactivity of tea tree (Melaleuca alternifolia) essential oil against larvae and adult forms of lesser mealworms (Alphitobius diaperinus) and its influence on the soil fauna. Tests were performed in triplicate using pure tea tree oil (TTO; 1, 5, 10, 25, 50, and 100%), TTO nanoparticles (1, 3, and 7.5%), or terpinen-4-ol, the main compound of the tea tree oil, at the same concentrations of TTO. Larvae and adult mortality occurred at concentrations up to 10 and 50% of TTO, respectively. No larvicidal or insecticidal effect of TTO nanoparticles was observed. Terpinen-4-ol showed insecticidal and larvicidal effect at concentrations higher than 25%. The evaluation of TTO effect on soil organisms was performed by standard ecotoxicological tests (ISO) with the springtail species Folsomia candida. Only TTO was used for ecotoxicological tests in doses of 1, 5, 10, 25, 50, and 100 mg kg-1 of soil. TTO had no negative effects on F. candida survival or reproduction. Therefore, it was concluded that M. alternifolia oil may be a new alternative for control of the lesser mealworm.(AU)

Assuntos

RESUMO

The aim of this study was to evaluate the in vitro bioactivity of tea tree (Melaleuca alternifolia) essential oil against larvae and adult forms of lesser mealworms (Alphitobius diaperinus) and its influence on the soil fauna. Tests were performed in triplicate using pure tea tree oil (TTO; 1, 5, 10, 25, 50, and 100%), TTO nanoparticles (1, 3, and 7.5%), or terpinen-4-ol, the main compound of the tea tree oil, at the same concentrations of TTO. Larvae and adult mortality occurred at concentrations up to 10 and 50% of TTO, respectively. No larvicidal or insecticidal effect of TTO nanoparticles was observed. Terpinen-4-ol showed insecticidal and larvicidal effect at concentrations higher than 25%. The evaluation of TTO effect on soil organisms was performed by standard ecotoxicological tests (ISO) with the springtail species Folsomia candida. Only TTO was used for ecotoxicological tests in doses of 1, 5, 10, 25, 50, and 100 mg kg-1 of soil. TTO had no negative effects on F. candida survival or reproduction. Therefore, it was concluded that M. alternifolia oil may be a new alternative for control of the lesser mealworm.

Assuntos