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1.
Sci Total Environ ; 845: 157324, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35843316

RESUMO

This study looked at the potential of thermal comfort provided to animals by four different Brazilian savanna (Cerrado) native trees, as well as their potential for carbon sink. The evaluations were carried out during the summer of 2020, which consisted of the collection of microclimate variables. The Mean Radiant Temperature (TMR, °C) was derived from the shaded and unshaded areas under the trees, and from that, the Radiant Heat Load (RHL, W m-2) was calculated as an index of thermal comfort. Solar radiation was estimated considering the sum of the direct, diffuse, and reflected components (W m-2), and carbon stock from trees biomass for CO2 sequestration was estimated from an allometric model applied to the native Cerrado tree species. The shade of the native trees reduced the meteorological variables such as dry bulb and black globe temperatures, to values considered adequate for the thermal comfort of animals, with an average reduction respectively equal to 1.3 °C and 6.4 °C. This represents a significant difference compared to the unshaded area as well as among tree species (P < 0.05), reflecting in lower values of TMR and RHL in the shaded area provided by each species. Carbon sequestration individually estimated by each native tree species was on average 8.85 Mg per tree. These results demonstrate the great potential for native tree species in the Cerrado biome to be used in agroforestry systems to provide higher levels of thermal comfort to animals and to combat climate change through their aptitude of CO2 sink.


Assuntos
Sequestro de Carbono , Árvores , Animais , Brasil , Dióxido de Carbono , Pradaria
2.
Int J Biometeorol ; 66(3): 535-544, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34716805

RESUMO

This work aimed to evaluate the thermal comfort provided by shading structures in free-range systems under a tropical environment, based on microclimate variables of nets with different materials. During the experiment, the unshading area; the natural shading of a native tree species to the Brazilian Savanna; and the artificial 80% shadings nets: black polypropylene, heat-reflective aluminized, and association of both were evaluated. The shading structures were analyzed in paddocks at the Água Limpa Farm from the University of Brasília, where dry-bulb, wet-bulb, black globe temperatures, and wind speed were collected for the micrometeorological characterization from 8:00 am to 4:00 pm. From the temperatures, the vapor pressures and the humidities were calculated. The shortwave radiation was calculated through the sum of direct, diffuse, and reflected radiations. The mean radiant temperature, radiant heat load, and black globe temperature and humidity index were calculated. The internal and external surface temperatures of the nets and the soil temperature were measured every 30 min. The data were analyzed with aid of the statistical analysis system. The air temperature varied according to the shortwave radiation, from 25.6 °C at 8:00 am to 29.6 °C at 1:00 pm, with a decrease over the hours. Despite the air temperature of the trees showed the lowest average, the nets association structure was the most reduced all the thermal comfort indexes. The heat-reflective net presented the lowest soil temperature at all hours (under 26.1 °C). In general, the shadings proved to be efficient in promoting thermal comfort in free-range systems.


Assuntos
Pradaria , Microclima , Umidade , Temperatura , Árvores
3.
J Therm Biol ; 88: 102489, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32125977

RESUMO

The aim of this work was to evaluate the thermal comfort of sows in a free-range system in the Brazilian Savanna, based on behavior observation, availability of shading resources, meteorological and physiological variables. The sows were analyzed in the gestation sector at Água Limpa Farm from University of Brasília; the sows were housed in paddocks of 1000 m2 each containing artificial and natural shading structures, where air temperature (Tair, °C), wind speed, relative humidity (RH, %) and black globe temperatures (TG, °C) were collected for the environment characterization in 20-min-intervals. From the black globe temperature, the Mean Radiant Temperature (TMR, °C) and the Radiant Heat Load (RHL, W m-2) were calculated in the sun and under the shade structures. The total short-wave irradiance was calculated through the sum of direct, diffuse and reflected radiations. For the behavioral evaluation, an ethogram was elaborated, taking in consideration where the animals were in the paddocks, body posture, and the activity performed. The physiological variables such as respiratory rate (breaths.min-1), surface and rectal temperatures (°C) were measured during the experiment. The data was statistically analyzed through analysis of variance and frequency analysis. There was a difference at 11a.m., 2 and 3p.m., with values above 40 °C under the shade and above 70 °C in the sun for the TMR. The preferential choice was for natural shading by the sows, due to the lower TMR and RHL throughout the day and resting activity had been predominated. The rectal temperature did not differ between the animals and the days evaluated, respiratory rate varied according to air temperature, and surface temperature only among the evaluated animals. It was concluded that even when there is a greater radiation incidence and meteorological variables above the condition of comfort for sows, they did not express any abnormal behavior that could indicate discomfort.


Assuntos
Regulação da Temperatura Corporal , Suínos/fisiologia , Animais , Comportamento Animal , Temperatura Corporal , Brasil , Feminino , Pradaria , Temperatura Alta , Taxa Respiratória , Luz Solar
4.
Ciênc. rural ; 44(1): 147-152, Jan. 2014. ilus
Artigo em Português | LILACS | ID: lil-697032

RESUMO

Listeria monocytogenes é um patógeno relevante veiculado por alimentos. Sua identificação precisa é importante para a correta determinação do risco associado à ingestão do alimento. O objetivo deste trabalho foi verificar a ocorrência das espécies de Listeria spp. em amostras de salsichas tipo hot dog e carne moída bovina, comercializadas a granel no Distrito Federal. Foram analisadas 162 amostras, sendo 127 de salsichas tipo hot dog e 35 amostras de carne moída bovina. O isolamento e a identificação do gênero foram feitos por metodologia convencional e a distinção das espécies foi verificada por kit bioquímico específico (API-Listeria®) e por análise de restrição de fragmentos da reação em cadeia da polimerase (RFLP-PCR) do gene 23 rRNA. Foram isoladas 26 cepas de Listeria spp. das amostras de salsichas tipo hot dog, sendo identificadas 18 cepas de Listeria innocua e 08 cepas de Listeria monocytogenes. Das 35 amostras de carne moída bovina, foram isoladas 16 cepas de Listeria spp., sendo identificadas 12 cepas de Listeria innocua e 04 de Listeria monocytogenes. Houve concordância total na distinção das espécies de Listeria spp. através dos dois métodos empregados. A presença de Listeria spp. em amostras de salsicha do tipo hot dog a granel e em carne moída bovina a granel, de estabelecimentos comerciais do Distrito Federal, representa risco à saúde do consumidor.


Listeria monocytogenes is a pathogen disclosed by foods. Its accurate identification is important for the correct determination of the risk associated with the ingestion of food. The aim of this research was to determine the occurrence of Listeria spp. in samples of hot dog sausages and ground beef, sold in bulk in the Federal District. A total of 162 samples, 127 hot dog sausages and 35 samples of ground beef cattle, were analyzed. The isolation and identification of the genus were made by conventional methodology and distinction of species was verified by specific biochemical kit (API-Listeria®) and by restriction fragment length polymorphism (PCR-RFLP) of 23S rRNA gene. Twenty-six strains of Listeria spp. were isolated. Samples of hot dog sausages identified 18 strains of Listeria innocua and 08 strains of Listeria monocytogenes. Of the 35 samples of ground beef cattle were isolated, 16 strains of Listeria spp., 12 strains of Listeria innocua and 04 strains of Listeria monocytogenes. There was total agreement in the distinction of Listeria species using the two methods. The presence of Listeria spp. in samples of hot dog sausages and ground beef, sold in bulk in commercial establishment of the Federal District represents a risk to consumer health.

5.
Braz. arch. biol. technol ; 53(3): 583-591, May-June 2010. graf, tab
Artigo em Inglês | LILACS | ID: lil-548578

RESUMO

Morphometric data was collected on 859 naturalized swine in Brazil (Piau, Tatu, Nilo, Caruncho, Casco de Burro, Moura, Monteiro and Rabo de Peixe), Colombia (Criolla Zungo, Sanpedreño and Casco de Mula) and Uruguay (Mamellado), both on farm and in published material. Information was collected on breed, sex and age, as well as various morphometric measurements. Analysis of variance was carried out using PROC MIXED of SAS ® on phenotypic data. The coefficients of variance varied between 11.50 and 83.81 percent, and the coefficient of determination was medium to high. Females were in general smaller for most measurements than males, showing sexual dimorphism. The Moura was the closest naturalized breed to the commercial breeds, followed by the Piau, while the Monteiro was the furtherest. The dendrogram obtained from morphological information showed a division of the pigs into three groups. Characterization was possible using morphological and morphometric data.


Foram colhidos dados morfométricos de 859 suínos naturalizados do Brasil (Piau, Tatu, Nilo, Caruncho, Casco de Burro, Moura, Monteiro e Rabo de Peixe), Colômbia (Criolla Zungo, Sanpedreño e Casco de Mula) e Uruguai (Mamellado) Dados sobre raça, sexo e idade foram coletados, assim como varias avaliações morfométricas. A análise de variância foi realizada utilizando-se o procedimento PROC GLM do SAS sobre os dados morfométricos. Os coeficientes de variância oscilaram de 11,50 a 83,81 por cento e o coeficiente de determinação foi de moderado a alto. As fêmeas foram em geral menores na maioria das avaliações em relação aos machos, indicando dimorfismo sexual. A Moura foi a raça naturalizada mais próxima das raças comerciais, seguida da Piau, enquanto a Monteiro apresentou-se mais distante. O dendograma obtido a partir de informações morfológicas apresentou divisão dentro de três grupos. A caracterização foi possível utilizando-se dados morfológicos e morfométricos.

6.
Int J Food Microbiol ; 139(1-2): 15-22, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20199820

RESUMO

The occurrence of foodborne diseases is increasing throughout the world. Bacteria of the genus Salmonella are responsible for food poisoning and, in some cases, may be fatal. The aim of this study was to adapt the multiplex PCR technique (mPCR) on the rapid and direct identification of the presence of Salmonella sp. as well as serotypes Enteritidis, Typhi and Typhimurium in poultry carcasses (n=127) and viscera (n=73). The implementation of the standard technique using positive controls was successfully adapted. The results of Salmonella sp. detection in refrigerated viscera showed that the mPCR was able to detect Salmonella genus in 2.74% of these samples. Traditional microbiological analysis also identified the same positive samples for Salmonella sp. but was not able to differentiate the serotype. The serotype Enteritidis was detected by mPCR in 1.37% of the samples. Our conclusion was that the mPCR was able to detect the presence of these bacteria in a short period of time and enabled the identification of serotype Enteritidis in one of the samples found positive for Salmonella sp.


Assuntos
Microbiologia de Alimentos , Carne/microbiologia , Reação em Cadeia da Polimerase/métodos , Aves Domésticas/microbiologia , Salmonella/isolamento & purificação , Animais , DNA Bacteriano/análise , Salmonella/genética , Intoxicação Alimentar por Salmonella/prevenção & controle , Salmonella enteritidis/genética , Salmonella enteritidis/isolamento & purificação , Salmonella typhi/genética , Salmonella typhi/isolamento & purificação , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Sorotipagem/métodos
7.
Ciênc. rural ; 40(2): 396-402, fev. 2010. ilus, tab
Artigo em Português | LILACS | ID: lil-539939

RESUMO

Foram analisados quatro grupos de ovinos machos da raça Santa Inês nascidos em quatro estações do ano, no Distrito Federal, a fim de observar as idades e o peso corporal em que estes atingiram a puberdade. A partir dos cortes histológicos dos testículos, foram analisados parâmetros celulares e mensurações dos túbulos seminíferos. O efeito da data de nascimento sobre os parâmetros avaliados foi significativo (P<0,01), indicando que a estação do ano influenciou as características histológicas dos testículos dos cordeiros Santa Inês. Os animais nascidos no período da seca apresentaram maior precocidade à puberdade, porém pior perfil histológico dos testículos. O final da época de águas apresentou-se como a melhor estação para nascimentos de ovinos na região Central do Brasil, com características histológicas testiculares mais desejáveis na puberdade desses animais.


Four groups of Santa Inês male sheep born in four seasons in the Distrito Federal were analyzed to evaluate the age and body weight at puberty, at which point were castrated. Histological measurements were carried out on the testicles to evaluate cellular parameters and size measurements of the seminiferous tubules. The effect of the group on cellular parameters was significant (P<0.01). Animals born in the dry season were more precocious than the others, but showed the worst histological profile of the testis. The histological traits of the testis of the Santa Inês rams were influenced by the season. The end of the rainy season was shown to the best season for births of sheep in the Central region of Brazil, with histological testicular traits at puberty being superior to the other groups.

8.
Braz. arch. biol. technol ; 52(4): 981-984, July/Aug. 2009. tab
Artigo em Inglês | LILACS | ID: lil-525619

RESUMO

Metabolizable energy (ME) of corn with different geometric diameters was determined in European quail with 26 days of age with 124 g of mean live weight, using the Total Collection of Excreta Method. One hundred and twenty five quails were divided in five treatments, five replications with five quails each, with one treatment used to determine endogenous losses. Values of Average Geometric Diameter (AGD) of the corn were 600, 800, 1000 and 1200 µm. ME of corn was not affected by AGD. Average values were 3079, 3274, 3300, 3137 Kcal/kg respectively for apparent metabolizable energy, corrected apparent metabolizable energy, true metabolizable energy, corrected true metabolizable energy.


Determinou-se o valor de energia metabolizável (EM) do milho com diferentes diâmetros geométrico médio em codornas com 26 dias de idade e 124 g de peso médio, utilizando-se a metodologia da coleta total de excretas. Foram utilizadas 125 codornas distribuídas em cinco tratamentos com cinco repetições de cinco aves, sendo um tratamento para determinar as perdas endógenas. Os valores de diâmetro geométrico médio (DGM) do milho estudado foram 600, 800, 1000 e 1200 µm. O DGM não apresentou influência significativa sobre a EM do milho que apresentou valores médios de 3079, 3274, 3300, verdadeira, energia metabolizável verdadeira corrigida.

9.
Ciênc. rural ; 38(9): 2587-2592, dez. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-498417

RESUMO

The aim of this research was to detect the principal reasons for condemnation of poultry carcasses in two slaughterhouses (A and B); located in the southeastern region of the State of Goiás, Brazil. The data were collected by the federal veterinary inspection services of the Brazilian Ministry of Agriculture between January and April 2007. The principal causes of condemnation observed in both industries were cellulite, contusion/ fractures and bruises, as well as contamination due to gut severance at evisceration. The three main values observed for each of the causes were different between the slaughter houses. In A, cellulite was the main cause of condemnation with 51.20% of all condemnations, followed by 5.67% for contusion/ fractures and bruising and 33.61% for contamination by evisceration. In B, the major cause of condemnation was 28.90% due to fractures/ contusion and bruising, followed by 25.27% for cellulite and 22.50% for contamination. Other causes of condemnation were observed, however in minute quantities in both industries (<10% to A and <23% to B). The high cellulite occurrence in A was due to the high density of the poultry in sheds (17 or 18 chickens m-2). The greater value for fractures/ contusion and bruising verified in B was due to the inefficiency during capture in the sheds and putting on hooks in the slaughterhouse. Carcass lesions were also caused by insensitization because of non-uniformity in the poultry groups. Contamination by residues due to gut severance, mainly intestines, was attributed to problems in adjustment of machinery and non- uniformity of lots in industry A. In industry B the value detected within an acceptable level of failure in evisceration for machine, according to the manufacturer. All problems observed suggest a failure in handling, cellulite and mainly failures in pre slaughter and slaughter procedure to prevent contusions, fractures and bruising.


O objetivo deste trabalho foi observar as principais causas de condenações de aves, em dois abatedouros frigoríficos (A e B), localizados na região Sudeste do Estado de Goiás, Brasil. Os dados foram obtidos junto ao serviço de inspeção veterinária federal do Ministério da Agricultura, entre o período de janeiro e abril de 2007. As três principais causas de condenações observadas em ambas as indústrias foram celulite, contusão/fratura e hematomas e contaminação devido à ruptura de vísceras no momento da evisceração. Entretanto, os valores observados, para cada uma das causas, foram diferentes entre os frigoríficos A e B. Em A, verificou-se que a celulite foi a maior causa de condenação, com 51,20 % do total de condenações, seguido por 5,67% de contusão/fratura e hematomas e 33,61% de contaminação na evisceração. Em B, a maior causa foi 28,90% para fraturas/ contusões e hematomas, seguido de 25,27% para celulite e 22,50% para contaminação. Outras causas de condenação também foram observadas, porém em pequenas percentagens para ambas as indústrias. Observou-se que, em A, a celulite estava relacionada à alta densidade de aves/m² nos galpões (17 a 18 aves m-2). O maior índice para fratura/contusões e hematomas observados em B foi relacionado à ineficiência na apanha e no enganchamento, bem como a traumas no momento da insensibilização devido à desuniformidade das aves. Para a contaminação por resíduos de rompimento de vísceras, principalmente alças intestinais, foi atribuído, para A, problemas na regulagem da máquina e desuniformidade do lote e, para B, o valor detectado estava dentro da margem aceitável de falhas na evisceração para a máquina evisceradora, segundo o fabricante. Os problemas verificados ainda sugerem falhas no manejo, no que se refere às celulites, e principalmente falhas nas operações de pré-abate e abate para os índices de contusões, fratura e hematomas.

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