Climate Parameters in the Trailer During the Transportation of One-Day-Old-Chicks

Various problems may arise during the road transportation of one-day-old broiler chickens from hatcheries to rearing houses. In this study, the transportation vehicles of a private company operating in the Bursa Region were physically examined, and the climate parameters of the trailer were observed. During these observations the exposure of animals to heat stress was measured, and the loss of life during transportation was revealed. Thirteen data logger values were placed in the trailer and their readings were recorded. While the highest heat stress is in the summer and the heat stress is the highest in the front and middle parts of the trailer, the least are in the first row and the last row in vehicles that use natural ventilation in the summer and mechanical air conditioning in the winter.(AU)

Annexin A1 peptide Ac2-26 mitigates ventilator-induced lung injury in acute respiratory distress syndrome rats and partly depended on the endothelial nitric oxide synthase pathway

Purpose: Although mechanical ventilation is an essential support for acute respiratory distress syndrome (ARDS), ventilation also leads to ventilator-induced lung injury (VILI). This study aimed to estimate the effect and mechanism of Annexin A1 peptide (Ac2-26) on VILI in ARDS rats. Methods: Thirty-two rats were randomized into the sham (S), mechanical ventilation (V), mechanical ventilation/Ac2-26 (VA), and mechanical ventilation/Ac2-26/L-NIO (VAL) groups. The S group only received anesthesia, and the other three groups received endotoxin and then ventilation for 4 h. Rats in the V, VA and VAL groups received saline, Ac2-26, and A c2-26/N5-(1-iminoethyl)-l-ornithine (L-NIO), respectively. Results: All indexes deteriorated in the V, VA and VAL groups compared with the S group. Compared with V group, the PaO2/FiO2 ratio was increased, but the wet-to-dry weight ratio and protein levels in bronchoalveolar lavage fluid were decreased in the VA group. The inflammatory cells and proinflammatory factors were reduced by Ac2-26. The oxidative stress response, lung injury and apoptosis were also decreased by Ac2-26 compared to V group. All improvements of Ac2-26 were partly reversed by L-NIO. Conclusions: Ac2-26 mitigates VILI in ARDS rats and partly depended on the endothelial nitric oxide synthase pathway.

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...

Femoral orthopedic implants in dogs with titanium - mechanical evaluation

Background: Orthopedic implants are commonly used for different types of surgical procedures to gain optimal functionand to provide stability to both bones and tendon structures. When inserting these implants, the characteristics of the material are important for surgical success, and the ideal implant must be biocompatible and nonallergenic. However, whenmolding an implant to the bone structure, its resistance can change significantly. Implants can be temporary or permanentin the body, and metal possesses properties that make it acceptable for bone repair. In biomedical implants, 2 types aremost common, commercially pure (CP)-Ti and Ti-6A1-4V. They both provide stable fixation and low risk of loosening.Implants made with the same material and composition can perform differently if the material has been altered by processing techniques for different scenarios. Stress, strain and elastic modulus are the primary metrics used in the description ofimplant materials. They can be calculated based on mechanical tests of specimens with defined geometry, most commonlytensile, bending and torsional tests. In order to better evaluate those changes, we compared the mechanical characteristicsof titanium bone plates, before and after they were molded to the bone, to verify and quantify the loss of stiffness andresistance after molding the plate.Materials, Methods & Results: The study was prospective. Orthopedic implant made of commercially pure titanium (CPTi) were divided into 2 groups, one group without plate molding and the other with plate molding to a dog femora bone.Thirty-six plates of different sizes (5.0, 6.5, 8.0, 9.0, 10.0- and 11.0-mm diameter) were divided into 6 groups containing6 plates of each size and submitted to the 4-point flexion test of resistance, using a piece of dog femur (weights of 5, 10,15, 20 and 25 kg) as the bone in which the...(AU)

Efficiency of cooling systems in broiler houses during hot days / Eficiência dos sistemas de resfriamento em aviários durante dias quentes

This study evaluated: (1) the vulnerability of broiler houses with different cooling systems, and (2) the spatial distribution of environmental variables during hot days. Four potentially vulnerable commercial broiler houses in southern Brazil were selected according to the following parameters: absence or presence of different cooling systems, broilers older than 28 days, and outside air dry-bulb temperature over 30°C. Broiler house vulnerability was classified according to the cooling and mechanical ventilation system: cellulose pad cooling (CPC), sprinkling (SPK), fogging (FOG), and mechanical ventilation without evaporative cooling system (VTL). The air dry-bulb temperature (Tdb, °C) and relative humidity (RH, %) were recorded every 10 min. For each broiler house, we evaluated: (1) relative cooling efficiency (RCE) and (2) inside spatial distribution of microclimate variables using a geostatistical technique. The CPC and SPK did not differ (P<0.05) in RCE (81.6% and 80.7%, respectively), but both differed from FOG (23.8%) and VLT (1.87%) systems. The highest variations in indoor Tdb were recorded in the FOG (7 °C), followed by the SPK (4 °C) and CPC (3 °C). In the CPC, there was an increase in RH from the middle to the end of the broiler house near the exhaust fans. In conclusion, the relative cooling efficiency and the inside spatial distributions of environmental variables in the broiler houses were influenced by the existing cooling system.

Os objetivos deste estudo foram (1) comparar a vulnerabilidade de aviários com diferentes sistemas de resfriamento, e (2) avaliar a distribuição espacial interna das variáveis ambientais durante dias quentes. Quatro aviários comerciais potencialmente vulneráveis no sul do Brasil foram selecionados de acordo com os seguintes parâmetros de elegibilidade: ausência ou presença de diferentes sistemas de resfriamento; frangos de corte com mais de 28 dias de idade; e temperatura de bulbo seco do ar externa acima de 30 °C. A vulnerabilidade do aviário foi classificada de acordo com o sistema de resfriamento e ventilação mecânica, sendo: resfriamento por pad cooling (CPC), aspersão (SPK), nebulização (FOG) e ventilação mecânica sem sistema de resfriamento evaporativo (VTL). A temperatura de bulbo seco do ar (Tbs, °C) e a umidade relativa do ar (UR, %) foram coletadas por registradores de dados autônomos a cada 10 min. Para cada aviário foram avaliados: (1) eficiência relativa de resfriamento (RCE) e (2) distribuição espacial interna das variáveis ambientais por técnica de geoestatística. O CPC e SPK não diferiram (P>0,05) na RCE (81,6% e 80,7% respectivamente), mas ambos diferiram do FOG (23,8%) e VLT (1,87%). As maiores variações na Tbs do ar interno foram registradas no FOG (7 °C), seguido pelo SPK (4 °C) e CPC (3 °C). No CPC, houve um aumento da umidade relativa do meio para o final do aviário, próximo aos exaustores. Em conclusão, a eficiência relativa de resfriamento, assim como a distribuição espacial das variáveis ambientais internas foram influenciadas pelo sistema de resfriamento de cada aviário.

Efficiency of cooling systems in broiler houses during hot days / Eficiência dos sistemas de resfriamento em aviários durante dias quentes

This study evaluated: (1) the vulnerability of broiler houses with different cooling systems, and (2) the spatial distribution of environmental variables during hot days. Four potentially vulnerable commercial broiler houses in southern Brazil were selected according to the following parameters: absence or presence of different cooling systems, broilers older than 28 days, and outside air dry-bulb temperature over 30°C. Broiler house vulnerability was classified according to the cooling and mechanical ventilation system: cellulose pad cooling (CPC), sprinkling (SPK), fogging (FOG), and mechanical ventilation without evaporative cooling system (VTL). The air dry-bulb temperature (Tdb, °C) and relative humidity (RH, %) were recorded every 10 min. For each broiler house, we evaluated: (1) relative cooling efficiency (RCE) and (2) inside spatial distribution of microclimate variables using a geostatistical technique. The CPC and SPK did not differ (P<0.05) in RCE (81.6% and 80.7%, respectively), but both differed from FOG (23.8%) and VLT (1.87%) systems. The highest variations in indoor Tdb were recorded in the FOG (7 °C), followed by the SPK (4 °C) and CPC (3 °C). In the CPC, there was an increase in RH from the middle to the end of the broiler house near the exhaust fans. In conclusion, the relative cooling efficiency and the inside spatial distributions of environmental variables in the broiler houses were influenced by the existing cooling system.(AU)

Os objetivos deste estudo foram (1) comparar a vulnerabilidade de aviários com diferentes sistemas de resfriamento, e (2) avaliar a distribuição espacial interna das variáveis ambientais durante dias quentes. Quatro aviários comerciais potencialmente vulneráveis no sul do Brasil foram selecionados de acordo com os seguintes parâmetros de elegibilidade: ausência ou presença de diferentes sistemas de resfriamento; frangos de corte com mais de 28 dias de idade; e temperatura de bulbo seco do ar externa acima de 30 °C. A vulnerabilidade do aviário foi classificada de acordo com o sistema de resfriamento e ventilação mecânica, sendo: resfriamento por pad cooling (CPC), aspersão (SPK), nebulização (FOG) e ventilação mecânica sem sistema de resfriamento evaporativo (VTL). A temperatura de bulbo seco do ar (Tbs, °C) e a umidade relativa do ar (UR, %) foram coletadas por registradores de dados autônomos a cada 10 min. Para cada aviário foram avaliados: (1) eficiência relativa de resfriamento (RCE) e (2) distribuição espacial interna das variáveis ambientais por técnica de geoestatística. O CPC e SPK não diferiram (P>0,05) na RCE (81,6% e 80,7% respectivamente), mas ambos diferiram do FOG (23,8%) e VLT (1,87%). As maiores variações na Tbs do ar interno foram registradas no FOG (7 °C), seguido pelo SPK (4 °C) e CPC (3 °C). No CPC, houve um aumento da umidade relativa do meio para o final do aviário, próximo aos exaustores. Em conclusão, a eficiência relativa de resfriamento, assim como a distribuição espacial das variáveis ambientais internas foram influenciadas pelo sistema de resfriamento de cada aviário.(AU)

Efficiency of cooling systems in broiler houses during hot days / Eficiência dos sistemas de resfriamento em aviários durante dias quentes

ABSTRACT: This study evaluated: (1) the vulnerability of broiler houses with different cooling systems, and (2) the spatial distribution of environmental variables during hot days. Four potentially vulnerable commercial broiler houses in southern Brazil were selected according to the following parameters: absence or presence of different cooling systems, broilers older than 28 days, and outside air dry-bulb temperature over 30°C. Broiler house vulnerability was classified according to the cooling and mechanical ventilation system: cellulose pad cooling (CPC), sprinkling (SPK), fogging (FOG), and mechanical ventilation without evaporative cooling system (VTL). The air dry-bulb temperature (Tdb, °C) and relative humidity (RH, %) were recorded every 10 min. For each broiler house, we evaluated: (1) relative cooling efficiency (RCE) and (2) inside spatial distribution of microclimate variables using a geostatistical technique. The CPC and SPK did not differ (P<0.05) in RCE (81.6% and 80.7%, respectively), but both differed from FOG (23.8%) and VLT (1.87%) systems. The highest variations in indoor Tdb were recorded in the FOG (7 °C), followed by the SPK (4 °C) and CPC (3 °C). In the CPC, there was an increase in RH from the middle to the end of the broiler house near the exhaust fans. In conclusion, the relative cooling efficiency and the inside spatial distributions of environmental variables in the broiler houses were influenced by the existing cooling system.

RESUMO: Os objetivos deste estudo foram (1) comparar a vulnerabilidade de aviários com diferentes sistemas de resfriamento, e (2) avaliar a distribuição espacial interna das variáveis ambientais durante dias quentes. Quatro aviários comerciais potencialmente vulneráveis no sul do Brasil foram selecionados de acordo com os seguintes parâmetros de elegibilidade: ausência ou presença de diferentes sistemas de resfriamento; frangos de corte com mais de 28 dias de idade; e temperatura de bulbo seco do ar externa acima de 30 °C. A vulnerabilidade do aviário foi classificada de acordo com o sistema de resfriamento e ventilação mecânica, sendo: resfriamento por pad cooling (CPC), aspersão (SPK), nebulização (FOG) e ventilação mecânica sem sistema de resfriamento evaporativo (VTL). A temperatura de bulbo seco do ar (Tbs, °C) e a umidade relativa do ar (UR, %) foram coletadas por registradores de dados autônomos a cada 10 min. Para cada aviário foram avaliados: (1) eficiência relativa de resfriamento (RCE) e (2) distribuição espacial interna das variáveis ambientais por técnica de geoestatística. O CPC e SPK não diferiram (P>0,05) na RCE (81,6% e 80,7% respectivamente), mas ambos diferiram do FOG (23,8%) e VLT (1,87%). As maiores variações na Tbs do ar interno foram registradas no FOG (7 °C), seguido pelo SPK (4 °C) e CPC (3 °C). No CPC, houve um aumento da umidade relativa do meio para o final do aviário, próximo aos exaustores. Em conclusão, a eficiência relativa de resfriamento, assim como a distribuição espacial das variáveis ambientais internas foram influenciadas pelo sistema de resfriamento de cada aviário.

Preconsolidation stress of gibbsitic and kaolinitic Oxisols under a multipractice conservationist coffee system / Pressão de pré-consolidação de Latossolos gibbsítico e caulinítico sob sistema de multipraticas conservacionista no cultivo cafeeiro

Our goal was to analyze the impact of a multipractice soil conservationist system on coffee production in tropical soils (LATOSSOLO VERMELHO-AMARELO caulinítico/kaolinitic Haplustox and LATOSSOLO VERMELHO-gibbsítico/gibbsitic Acrustox) in Minas Gerais, Brazil. In the experimental area, the soil management involved a set of multiple conservationist practices during cultivation for more than 3.5 yrs. Soil samples were collected at 0-5, 10-15, and 20-25 cm depths at two positions: planting rows and between rows. The soil physical and mechanical properties were determined, with a focus mainly on the preconsolidation stress model (preconsolidation stress versus matric tension). For the purpose of analysis, a split-split plot experimental design was implemented. A linear mixed regression model (LMR) was fitted, and Wald's test was performed (P < 0.05). An improvement of soil physical quality for both Oxisols was observed at the planting row position. The effects of multipractice soil management after 3.5 yrs of cultivation in association with increased gibbsite content could promote new soil structure organization, as revealed by LMR, resulting in more resilient soils (between rows) and increasing the resistance to external pressures on gibbsitic Acrustox. Overall, the findings herein are in concordance with global trends towards conservationist practices that may alleviate soil compaction in agricultural systems to maintain environmental sustainability.(AU)

Nosso objetivo foi analisar o impacto de um sistema de manejo do solo com multi-práticas conservacionistas para o cultivo cafeeiro em solos tropicais (LATOSSOLO VERMELHO-AMARELO caulinítico/ kaolinitic Haplustox and LATOSSOLO VERMELHO gibbsítico/ gibbsitic Acrustox) em Minas Gerais, Brasil. Na área experimental, o manejo do solo incluiu um conjunto de multi-práticas conservacionistas por mais de 3,5 anos. Amostras de solo foram coletadas em 0-5; 10-15; e profundidades de 20 a 25 cm em duas posições: linha e entrelinha. As propriedades físicas e mecânicas do solo foram determinadas, concentrando-se principalmente na modelagem da compactação (estresse de pré-consolidação versus tensão matricial). Para fins de análise, foi considerado o delineamento experimental de parcelas subsubdivididas. Foi ajustado o modelo de regressão linear mista (RLM), bem como o teste F de Wald (P < 0,05). Melhorias na qualidade física do solo em ambos os Latossolos foi observada na linha de plantio. Os efeitos do sistema de manejo multipráticas usado após 3,5 anos de cultivo associado ao maior conteúdo de gibbsita podem promover uma nova organização da estrutura do solo revelada pelo RLM, que resulta em solos mais resilientes (na entrelinha), melhorando a resistência às pressões externas aplicadas ao Latossolo gibbsítico. No geral, os resultados aqui apresentadas estão de acordo com as tendências globais em direção a práticas conservacionistas que podem aliviar a compactação do solo em sistemas agrícolas e manter a sustentabilidade ambiental.(AU)

Do dietary stresses affect the immune system of Periplaneta americana (Blattaria: Blattidae)? / Estresses alimentares afetam o sistema immune de Periplaneta americana (Blattaria: Blattidae)?

Stresses can be caused by multiple biotic and abiotic factors and their effects can affect both the biology and the immune system of insects. American cockroach - Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) -besides being an excellent model species, has great medical importance because it can act as a mechanical vector of several pathogens. This study aimed to evaluate the influence of starvation, dehydration and both stresses on weight, and total and differential haemocyte count in P. americana adults. Each specimen was isolated in glass flasks containing or not food and/or water. They were weighed periodically. Another group received water for 24 h after the end of stress period. In the immunologic bioassay, we counted their haemocytes after the final weighing. All stresses reduced the insect weight, especially when the stresses were combined. Females of the control group gained weight and males had it unaltered. Different stress conditions and time did not influence on total haemocyte count. Insects without food and water had the proportion of prohaemocytes increased and plasmatocytes decreased. This study can serve as a basis of further studies of bioecology, behaviour and the ability of resisting insecticides, besides serving as a model to studies in other insect species.(AU)

Os estresses podem ser causados por múltiplos fatores bióticos e abióticos e seus efeitos podem afetar tanto a biologia como o sistema imune dos insetos. A barata-americana - Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) - além de ser uma excelente espécie modelo, tem grande importância médica, pois pode atuar como vetor mecânico de diversos patógenos. O objetivo desse estudo foi avaliar a influência da inanição, desidratação e ambos os estresses sobre o peso e o número total e diferencial de hemócitos em adultos de P. americana. Cada espécime foi isolado em frascos de vidro contendo ou não alimento e/ou água. Eles foram pesados periodicamente. Outro grupo recebeu água por 24 h após o término do período de estresse. Nos ensaios imunológicos, foram contados os seus hemócitos após a última pesagem. Todos os estresses reduziram o peso dos insetos, especialmente quando os estresses foram combinados. As fêmeas do grupo controle ganharam peso e os machos tiveram seu peso inalterado. As diferentes condições de estresse e tempo não influenciaram no número total de hemócitos. Os insetos sem alimento e água tiveram a proporção de pró-hemócitos aumentada e a de plasmatócitos reduzida. Esse estudo pode servir como base para estudos posteriores de bioecologia, comportamento e da habilidade de resistir aos inseticidas químicos, além de servir como modelo para estudos em outras espécies de insetos.(AU)

Mechanical properties of the sciatic nerve following combined transplantation of analytically extracted acellular allogeneic nerve and adipose-derived mesenchymal stem cells

Purpose To investigate the effects of Chemically Extracted Acellular Nerves (CEANs) when combined with Adipose-Derived mesenchymal Stem Cell (ADSC) transplantation on the repair of sciatic nerve defects in rabbits. Methods A total of 71 six-month-old Japanese rabbit were used in this study. Twenty rabbits served as sciatic nerve donors, while the other 51 rabbits were randomly divided into Autologous Nerve Transplantation Group (ANT, n=17), CEAN group (n=17) and CEAN-ADSCs group (n=17). In all these groups, the rabbits left sciatic nerves were injured before the experiment, and the uninjured sciatic nerves on their right side were used as the control (CON). Electrophysiological tests were carried out and sciatic nerves were prepared for histomorphology and stretch testing at 24 weeks post-transplant. Results There were significant differences between ANT and Con groups in amplitude (AMP): P=0.031; motor nerve conduction velocity (MNCV): P=0.029; Maximum stress: P=0.029; and Maximum strain P=0.027. There were also differences between the CEAN and CEAN+ADSCs groups in AMP: P=0.026, MNCV: P=0.024; Maximum stress: P=0.025 and Maximum strain: P=0.030. No significant differences in these parameters were observed when comparing the ANT and CEAN+SACN groups (MNCV: P=0.071) or the CEAN and ANT groups (Maximum stress: P=0.069; Maximum strain P=0.077). Conclusion Addition of ADSCs has a significant impact on the recovery of nerve function, morphology, and tensile mechanical properties following sciatic nerve injury.(AU)

Positive-reinforcement strategies to reduce capture-stress in Capybaras

Prior to the administration of any anesthetics, capturing the semi-aquatic capybara (Hydrochoerus hydrochaeris) demands physical restraint, which presents immense challenges. Traditional methods, such as lassoing and traps, are prone to induce acute stress, may result in injury, and can even have fatal outcomes. As part of a larger population control project using contraceptive methods, frequent capture-induced stress and injury may directly affect normal reproductive physiology. Thus, choosing a less stress-inducing method was imperative. In this report, we describe methods of conditioning to enable frequent capture and manipulation, using bait as a positive reinforcement associated with a special click-sound, in a free-ranging populationof 40 capybaras. The objectives were to attract, herd, and allow capybaras to voluntarily enter a coral. We evaluated the conditioning effect on individual and group behaviors, interpreting vocal and body language manifestations during the processes of conditioning, herding, capture, and recovery (post procedure/chemical restraint), with the aim of minimizing capture-related stress and injuries. Based on our observations, we report that conditioning, used as part of the capture strategies, noticeably facilitated physical restraint and manipulation throughout the procedures, while apparently maintaining the animals’ overall welfare as it relates to conditioning and capture.

Soil compaction on traffic lane due to soil tillage and sugarcane mechanical harvesting operations

Mechanical sugarcane harvesting increases soil compaction due to the intense traffic of agricultural machinery, reducing longevity of sugarcane crops. In order to mitigate the harmful effects caused by agricultural traffic on the soil structure in sugarcane fields, this study evaluated impacts of mechanical sugarcane harvesting on traffic lane under two soil tillage systems based on load bearing capacity models. The experiment was carried out in the region of Piracicaba, state of São Paulo, Brazil, on a Rhodic Nitisol, under conventional tillage (CT) and deep strip-tillage (DST). For CT soil tillage was applied to the entire area with a heavy disk harrow, at operating depths from 0.20 to 0.30 m followed by a leveling harrow at a depth of 0.15 m. For DST, soil tillage was performed in part of the area at a depth of 0.80 m, forming strip beds for sugarcane planting, while the traffic lanes were not disturbed. Undisturbed soil samples from traffic lanes were used in the uniaxial compression test to quantify preconsolidation pressure and to model the soil load bearing capacity. The surface layer (0.00-0.10 m) was most susceptible to compaction, regardless of the tillage system (CT or DST) used. In the DST, the traffic lane maintained the previous soil stress history and presented higher load bearing capacity (LBC) than the traffic lane in the CT. As in CT the soil was tilled, the stress history was discontinued. This larger LBC in DTS minimized the impacts of the sugarcane harvest. Under CT, additional soil compaction due to mechanical sugarcane harvesting in the traffic lane was observed after the second sugarcane harvest. There was a reduction in load bearing capacity from 165 kPa to 68 kPa under CT and from 230 kPa to 108 kPa under DST, from the first to the second harvest at surface layer. Water content at mechanical harvesting was the most relevant factor to maximize impacts on the soil structure in traffic lanes, for both tillage systems.

Soil compaction on traffic lane due to soil tillage and sugarcane mechanical harvesting operations

Mechanical sugarcane harvesting increases soil compaction due to the intense traffic of agricultural machinery, reducing longevity of sugarcane crops. In order to mitigate the harmful effects caused by agricultural traffic on the soil structure in sugarcane fields, this study evaluated impacts of mechanical sugarcane harvesting on traffic lane under two soil tillage systems based on load bearing capacity models. The experiment was carried out in the region of Piracicaba, state of São Paulo, Brazil, on a Rhodic Nitisol, under conventional tillage (CT) and deep strip-tillage (DST). For CT soil tillage was applied to the entire area with a heavy disk harrow, at operating depths from 0.20 to 0.30 m followed by a leveling harrow at a depth of 0.15 m. For DST, soil tillage was performed in part of the area at a depth of 0.80 m, forming strip beds for sugarcane planting, while the traffic lanes were not disturbed. Undisturbed soil samples from traffic lanes were used in the uniaxial compression test to quantify preconsolidation pressure and to model the soil load bearing capacity. The surface layer (0.00-0.10 m) was most susceptible to compaction, regardless of the tillage system (CT or DST) used. In the DST, the traffic lane maintained the previous soil stress history and presented higher load bearing capacity (LBC) than the traffic lane in the CT. As in CT the soil was tilled, the stress history was discontinued. This larger LBC in DTS minimized the impacts of the sugarcane harvest. Under CT, additional soil compaction due to mechanical sugarcane harvesting in the traffic lane was observed after the second sugarcane harvest. There was a reduction in load bearing capacity from 165 kPa to 68 kPa under CT and from 230 kPa to 108 kPa under DST, from the first to the second harvest at surface layer. Water content at mechanical harvesting was the most relevant factor to maximize impacts on the soil structure in traffic lanes, for both tillage systems.(AU)

Fatores de risco associados à retenção de placenta em vacas holandesas / Risk factors associated to retained placenta in Holstein cows

Background: Retained placenta (RP) is characterized by a failure to remove the fetal membranes within the first 12-24h after calving. This condition appears to be related to a decrease in neutrophil activity and to the suppression of the immune response in the prepartum period. The specific reasons for some cows to retain the placenta after parturition is stillnot fully understood, but numerous predisposing factors have been related, which may include mechanical, nutritional,infectious and handling factors. The aim of this study was to analyze the occurrence of retained placenta in dairy cowsand to correlate the main predisposing factors related.Materials, Methods & Results: This study was conducted in nine dairy farms located in the Rio Grande do Sul state,Brazil, with an average of 45 lactating dairy cows producing 10,100 kg / dairy cow in a period of 305 days. The total dietfor postpartum cows was estimated to meet or exceed the requirements of dairy cows according to previously establishedguidelines (NRC 2001). A total of 393 calving Holstein cows (126 primiparous and 267 multiparous) were analyzed, ofwhich 203 were kept in a semi-confined production system (free-stall and pasture system) and 190 animals were kept ina free-stall production system. Statistically, the cows were the experimental unit, and the results were analyzed using thePearson’s Chi-squared test or Fisher’s exact test for the comparisons of occurrence of peripartum disorders. In addition,linear and logistic regression models were constructed to determine the effect of the dependent variable on the other indicators, which may be continuous or categorical. Possible correlations of the occurrence of peripartum disorders relatedto production system (free-stall or semi-confined), calving order (primiparous or multiparous), season of the year (heator cold), ECC at calving (1 to 5), calf sex, rectal temperature and dystocia were analyzed. Of the 393 deliveries followedup in...

Fatores de risco associados à retenção de placenta em vacas holandesas / Risk factors associated to retained placenta in Holstein cows

Background: Retained placenta (RP) is characterized by a failure to remove the fetal membranes within the first 12-24h after calving. This condition appears to be related to a decrease in neutrophil activity and to the suppression of the immune response in the prepartum period. The specific reasons for some cows to retain the placenta after parturition is stillnot fully understood, but numerous predisposing factors have been related, which may include mechanical, nutritional,infectious and handling factors. The aim of this study was to analyze the occurrence of retained placenta in dairy cowsand to correlate the main predisposing factors related.Materials, Methods & Results: This study was conducted in nine dairy farms located in the Rio Grande do Sul state,Brazil, with an average of 45 lactating dairy cows producing 10,100 kg / dairy cow in a period of 305 days. The total dietfor postpartum cows was estimated to meet or exceed the requirements of dairy cows according to previously establishedguidelines (NRC 2001). A total of 393 calving Holstein cows (126 primiparous and 267 multiparous) were analyzed, ofwhich 203 were kept in a semi-confined production system (free-stall and pasture system) and 190 animals were kept ina free-stall production system. Statistically, the cows were the experimental unit, and the results were analyzed using thePearsons Chi-squared test or Fishers exact test for the comparisons of occurrence of peripartum disorders. In addition,linear and logistic regression models were constructed to determine the effect of the dependent variable on the other indicators, which may be continuous or categorical. Possible correlations of the occurrence of peripartum disorders relatedto production system (free-stall or semi-confined), calving order (primiparous or multiparous), season of the year (heator cold), ECC at calving (1 to 5), calf sex, rectal temperature and dystocia were analyzed. Of the 393 deliveries followedup in...(AU)

Do dietary stresses affect the immune system of Periplaneta americana (Blattaria: Blattidae)?

Abstract Stresses can be caused by multiple biotic and abiotic factors and their effects can affect both the biology and the immune system of insects. American cockroach Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) besides being an excellent model species, has great medical importance because it can act as a mechanical vector of several pathogens. This study aimed to evaluate the influence of starvation, dehydration and both stresses on weight, and total and differential haemocyte count in P. americana adults. Each specimen was isolated in glass flasks containing or not food and/or water. They were weighed periodically. Another group received water for 24 h after the end of stress period. In the immunologic bioassay, we counted their haemocytes after the final weighing. All stresses reduced the insect weight, especially when the stresses were combined. Females of the control group gained weight and males had it unaltered. Different stress conditions and time did not influence on total haemocyte count. Insects without food and water had the proportion of prohaemocytes increased and plasmatocytes decreased. This study can serve as a basis of further studies of bioecology, behaviour and the ability of resisting insecticides, besides serving as a model to studies in other insect species.

Resumo Os estresses podem ser causados por múltiplos fatores bióticos e abióticos e seus efeitos podem afetar tanto a biologia como o sistema imune dos insetos. A barata-americana Periplaneta americana (Linnaeus, 1758) (Blattaria: Blattidae) além de ser uma excelente espécie modelo, tem grande importância médica, pois pode atuar como vetor mecânico de diversos patógenos. O objetivo desse estudo foi avaliar a influência da inanição, desidratação e ambos os estresses sobre o peso e o número total e diferencial de hemócitos em adultos de P. americana. Cada espécime foi isolado em frascos de vidro contendo ou não alimento e/ou água. Eles foram pesados periodicamente. Outro grupo recebeu água por 24 h após o término do período de estresse. Nos ensaios imunológicos, foram contados os seus hemócitos após a última pesagem. Todos os estresses reduziram o peso dos insetos, especialmente quando os estresses foram combinados. As fêmeas do grupo controle ganharam peso e os machos tiveram seu peso inalterado. As diferentes condições de estresse e tempo não influenciaram no número total de hemócitos. Os insetos sem alimento e água tiveram a proporção de pró-hemócitos aumentada e a de plasmatócitos reduzida. Esse estudo pode servir como base para estudos posteriores de bioecologia, comportamento e da habilidade de resistir aos inseticidas químicos, além de servir como modelo para estudos em outras espécies de insetos.

Strategies to increment in vivo and in vitro embryo production and transfer in cattle

Knowledge of follicular wave dynamics obtained through the use of real-time ultrasonography and the development of the means by which follicular wave dynamics can be controlled have provided practical approaches for the in vivo and in vitro production and transfer of embryos in cattle. The elective control of follicular wave emergence and ovulation has had a great impact on the application of on-farm embryo transfer, especially when large groups of donors need to be superstimulated at the same time. Although estradiol and progestins have been used for many years, practitioners in countries where estradiol cannot be used have turned to alternative treatments, such as mechanical follicle ablation or the administration of GnRH for the synchronization of follicle wave emergence. In vitro embryo production also benefits from the synchronization of follicle wave emergence prior to Cumulus Oocyte Complexes (COCs) recovery. As Bos indicus cattle have high antral follicle population, large numbers of oocytes can be obtained by ovum pick-up (OPU) without superstimulation. However, synchronization of follicular wave emergence and superstimulation is necessary to obtain high numbers of COCs by OPU and blastocysts following in vitro fertilization in Bos taurus donors. Finally, embryos can now be transferred in commercial beef or dairy herds using efficacious synchronization and resynchronization protocols that are easily implemented by farm personnel. These technologies can also be used to resolve reproductive problems such as the reduced fertility observed during summer heat stress and/or in repeat-breeder cows in commercial dairy herds.

Strategies to increment in vivo and in vitro embryo production and transfer in cattle

Knowledge of follicular wave dynamics obtained through the use of real-time ultrasonography and the development of the means by which follicular wave dynamics can be controlled have provided practical approaches for the in vivo and in vitro production and transfer of embryos in cattle. The elective control of follicular wave emergence and ovulation has had a great impact on the application of on-farm embryo transfer, especially when large groups of donors need to be superstimulated at the same time. Although estradiol and progestins have been used for many years, practitioners in countries where estradiol cannot be used have turned to alternative treatments, such as mechanical follicle ablation or the administration of GnRH for the synchronization of follicle wave emergence. In vitro embryo production also benefits from the synchronization of follicle wave emergence prior to Cumulus Oocyte Complexes (COCs) recovery. As Bos indicus cattle have high antral follicle population, large numbers of oocytes can be obtained by ovum pick-up (OPU) without superstimulation. However, synchronization of follicular wave emergence and superstimulation is necessary to obtain high numbers of COCs by OPU and blastocysts following in vitro fertilization in Bos taurus donors. Finally, embryos can now be transferred in commercial beef or dairy herds using efficacious synchronization and resynchronization protocols that are easily implemented by farm personnel. These technologies can also be used to resolve reproductive problems such as the reduced fertility observed during summer heat stress and/or in repeat-breeder cows in commercial dairy herds.(AU)

Hemólise interfere na mensuração dos biomarcadores plasmáticos de estresse oxidativo em cães / Hemolysis interferes in the measurement of plasma biomakers of oxidative stress in dogs

Considerando que, entre todas as fontes de erro analítico, a hemólise é a mais importante na rotina laboratorial, o presente estudo teve como objetivo investigar o efeito da hemólise in vitro sobre os principais biomarcadores plasmáticos de estresse oxidativo mensurados (BPEO) de cães. Para tal, amostras de sangue total de 19 cães clinicamente saudáveis foram hemolisadas em diferentes graus por ação mecânica. Amostras controle contendo baixa concentração de hemoglobina (Hb) no plasma foram comparadas com quatro graus de hemólise (<0,36; 0,36-0,60; 0,61-1,0; 1,1-4g/L Hb). Imediatamente após a hemólise, foram mensuradas as concentrações plasmáticas de ácido úrico (AU), albumina, bilirrubina, gamaglutamiltransferase (GGT), capacidade antioxidante total (TAC) e concentração de oxidante total (TOC). Os erros relativos causados pelos diferentes graus de hemólises foram calculados e confrontados com o erro total aceitável (ETA) e com o limite de erro permitido (LEP) empregados nos programas de controle de qualidade de exames laboratoriais. Foi observado que mesmo pequeno grau de hemólise gera algum erro analítico não aceitável (ETA e/ou LEP) nos BPEO mensurados, exceto na bilirrubina. Foi possível concluir que a hemólise é um fator limitante para avaliação do estresse oxidativo sistêmico mensurado no plasma, podendo causar erros que potencialmente comprometem o diagnóstico clínico.(AU)

Among all the various sources of analytical error, hemolysis is the most important in the laboratory routine. The present study aimed to investigate the effect of hemolysis "in vitro" on the main plasma biomarkers of oxidative stress (BPEO) dogs. For this purpose, whole blood samples from 19 healthy dogs were hemolyzed in different degrees by mechanical action. Control samples containing low concentration of hemoglobin (Hb) levels in plasma were compared with four degrees of hemolysis (<0.36, from 0.36 to 0.60, 0.61 to 1.0, 1.1 to 4g/L Hb). Immediately after causing hemolysis, plasma concentrations of uric acid (UA), albumin, bilirubin, gamma glutamyl transferase (GGT), total antioxidant capacity (TAC), and total oxidant concentration (TOC) were measured. The relative errors caused by several levels of hemolysis were calculated and compared with the total acceptable error (TAE) and allowed error limit (LEP) by employees in quality control programs for laboratory tests. Even small levels of hemolysis generate unacceptable analytical error (TAE and / or LEP) in BPEO measured, except for bilirubin. Hemolysis is a limiting factor for the assessment of systemic oxidative stress measured in plasma and may cause errors that potentially compromise clinical diagnosis.(AU)

Hemólise interfere na mensuração dos biomarcadores plasmáticos de estresse oxidativo em cães / Hemolysis interferes in the measurement of plasma biomakers of oxidative stress in dogs

Considerando que, entre todas as fontes de erro analítico, a hemólise é a mais importante na rotina laboratorial, o presente estudo teve como objetivo investigar o efeito da hemólise in vitro sobre os principais biomarcadores plasmáticos de estresse oxidativo mensurados (BPEO) de cães. Para tal, amostras de sangue total de 19 cães clinicamente saudáveis foram hemolisadas em diferentes graus por ação mecânica. Amostras controle contendo baixa concentração de hemoglobina (Hb) no plasma foram comparadas com quatro graus de hemólise (<0,36; 0,36-0,60; 0,61-1,0; 1,1-4g/L Hb). Imediatamente após a hemólise, foram mensuradas as concentrações plasmáticas de ácido úrico (AU), albumina, bilirrubina, gamaglutamiltransferase (GGT), capacidade antioxidante total (TAC) e concentração de oxidante total (TOC). Os erros relativos causados pelos diferentes graus de hemólises foram calculados e confrontados com o erro total aceitável (ETA) e com o limite de erro permitido (LEP) empregados nos programas de controle de qualidade de exames laboratoriais. Foi observado que mesmo pequeno grau de hemólise gera algum erro analítico não aceitável (ETA e/ou LEP) nos BPEO mensurados, exceto na bilirrubina. Foi possível concluir que a hemólise é um fator limitante para avaliação do estresse oxidativo sistêmico mensurado no plasma, podendo causar erros que potencialmente comprometem o diagnóstico clínico.(AU)

Among all the various sources of analytical error, hemolysis is the most important in the laboratory routine. The present study aimed to investigate the effect of hemolysis "in vitro" on the main plasma biomarkers of oxidative stress (BPEO) dogs. For this purpose, whole blood samples from 19 healthy dogs were hemolyzed in different degrees by mechanical action. Control samples containing low concentration of hemoglobin (Hb) levels in plasma were compared with four degrees of hemolysis (<0.36, from 0.36 to 0.60, 0.61 to 1.0, 1.1 to 4g/L Hb). Immediately after causing hemolysis, plasma concentrations of uric acid (UA), albumin, bilirubin, gamma glutamyl transferase (GGT), total antioxidant capacity (TAC), and total oxidant concentration (TOC) were measured. The relative errors caused by several levels of hemolysis were calculated and compared with the total acceptable error (TAE) and allowed error limit (LEP) by employees in quality control programs for laboratory tests. Even small levels of hemolysis generate unacceptable analytical error (TAE and / or LEP) in BPEO measured, except for bilirubin. Hemolysis is a limiting factor for the assessment of systemic oxidative stress measured in plasma and may cause errors that potentially compromise clinical diagnosis.(AU)