Evaluation of thermal transport of day-old chicks / Avaliação térmica do transporte de pintos de um dia

The combining factors during initial handling might affect the broiler growth during the last week. Other factors might be considered, such as: fasting time, distance between hatchery and farm, vibration level, road quality, travel time, type of boxes and controlling environment inside the lorry. The aim of this work was to assess the thermal profile of truck with different levels of box placement during day-old chickens transport. An experiment was conducted through monitoring of 11 transport loads, with maximum capacity of 630 day-old chickens boxes, totalizing 63,000 animals. The day-old chicken transport truck (approximately 8 × 2.50 m, 2.50 m high) was environmentally controlled, with three box stacks (left, right and center) spaced 0.7 m. Air temperature, wind speed and humidity were controlled by sensors and electronic panel located in the truck cab. The set points for thermal conditions were: temperature between 23 and 25C and relative humidity between 60 and 70%. To characterize the environmental condition during transport, the following thermal variables were used: dry-bulb temperature, relative humidity and specific enthalpy, through data loggers (Onset, HOBO) programmed to record data at 10 minute intervals. Data was registered in two levels of the load (first rack and floor) where 17 data loggers were distributed throughout the truck. The experiment used a complet

O artigo não apresenta resumo em português.

The negative effects of mechanical vibrations on transport of fertile eggs / Os efeitos negativos das vibrações mecânicas no tranporte de ovos fertilizados

Mechanical vibrations resulted from transportation are mentioned to be a high hazardous issue of integrity and physiology found in biological systems. Fertile eggs that are transported from broiler farm to hatcheries are susceptible to harmful results, and it is still unknown all the possible effects in embryo development. Thus, the goal of this study was to evaluate the loss during hatching and in the quality of broiler chicks, after fertile eggs were exposed to simulated mechanical vibrations in different conditions. The experiment was developed in a commercial hatchery in Mogi-Mirim, São Paulo. Altogether, 1920 fertile eggs from Cobb-500 (31 to 34 weeks) were used. These eggs were exposed to vibrations during the transport in a mechanical simulator (Figure 1a). The assay was performed in a random modeling in blocks arranged in a factorial 2 x 2 + 1 with an additional treatment. The analyzed factors were determined by two vibration levels (lower with RSS 2.5 m/s2 and higher with RSS 7.5 m/s2), associated with two periods of exposition time (60 and 180 minutes). For the results, the answers from birth were analyzed using the hatching rate. The quality of broiler chicks obtained by the amount of first line chicks; and the total loss in the hatchery found in the summation of previous answers. Analyzes were done using a modeling of logistical regression, the effects of significan

O artigo não apresenta resumo em português.

Quality of fertilized eggs exposed to simulated mechanical vibrations condition / Qualidade de ovos fertilizados expostos a condições simuladas de vibrações mecânicas

The fertile egg transport is a crucial issue in the Brazilian broiler aviculture chain. Therefore, many agents intrinsically connected to this process such as the mechanical vibrations, can jeopardize the integrity of this fragile load. Given to this threatening problem the aim of this research was to assess the quality of fertile eggs exposed to different simulated conditions of mechanical vibrations. A mechanical agitator was developed to reproduce the treatments of this study, which were formed by 2 vibration levels. An inferior (instantaneous acceleration, up to 5 m s-2) and a superior (instantaneous acceleration above 10 m/s2), in which they were applied in 2 exposition times, a minimum (60 minutes) and a maximum (180 minutes), making the treatments T1, T2, T3, T4. The assay was conducted in a random modeling in 4 complete blocks that represented the factorial repetitions 2 x 2 +1, with an additional treatment (control). In the total, 2016 eggs from the same batch of matrixes (Cobb-500) in the peak egg reproduction (32-35 weeks) were used. From these eggs, 1920 were exposed to the 4 factorial treatment vibrations (480 eggs per treatment), meanwhile, the remaining 96 were used as control treatment. Among the vibrated eggs, 96 per treatment were sampled in order to be analyzed. In addition, some factors were verified: the diameter and the egg yolk height (EYD and EYH), the d

O artigo não apresenta resumo em português.

Vibrations and mechanical shocks in different roads during the transport of day-old chickes / Vibrações e choques mecânicos em diferentes estradas durante o transporte de pintos de um dia

The vibration and mechanical shocks that occur during the transport of chicks may act as a stressor of birds. The quality of roads also has serious impacts on load, because most vehicles are not designed to reduce vibration felt by the animals. The aim of this study was to evaluate the transport of day-old chicks on different roads, through vibration and shock of the trucks.  The research was conducted in a poultry integrator company located at state of São Paulo, through the monitoring of 11 shipments of chicks. The day-old chicken transport truck (approximately 8 x 2.50 m, 2.50 m high) was environmentally controlled, with three box stacks (left, right and center) spaced 0.7 m and two axis, with a capacity of 630 boxes of chicks, totaling an average of 63,000 chicks. The vibration levels reviews RMS X (vertical vibration), RMS Z (horizontal vibration) and RSS (general acceleration) and shocks on the dirt and asphalt roads were recorded using three triaxial accelerometers. The experimental design was completely randomized in an 11 x 2 factorial. Difference in vibration levels between dirt roads and asphalt, for RMS X, RMS Z and RSS, with the highest means were observed on the dirt road (P 0.05). However there was no statistical difference between the roads to the RMS Y (Table 1). This event can be attributed to the large irregularities and holes in dirt track. Generally thes

ês.

Influence of technical training on human-animal interactions at milking / Influência do treinamento técnico sobre interações humano-animal na ordenha

Faced with the prominent developments in breeding dairy cattle systems in Brazil, it is observed that the aspects related to animal welfare (AW) and the human-animal relationship did not achieve the same breakthrough. Thus, actions are needed that may generate positive changes in human-animal relationship, which relates closely to the AW and productivity in dairy cows. Therefore, this work aimed to evaluate the human-animal interactions at milking and the influence of technical training on these interactions. The research was divided into four stages. The first step consisted in selecting of six dairy farms based on pasture in São Paulo State. The second step was the evaluation of milking and the action of workers through the proposed protocol by Hemsworth et al. (2002): moving the cows in the shed for milking line activities; forcing the cows in the milking position; coupling and uncoupling the liners and moving the cows out of the milking line. Tactile interactions of humans toward the cows were classified as positive (POS) or negative (NEG), which were considered positive interactions "patting", affection or support hand on the back, legs or flanks of the cow, whereas negative interactions included slaps , shoving, or blows with the hand or with objects of any type. In the third stage, it was realized the technical training on good practices for the AW with the workers of th

O artigo não apresenta resumo em português.

Objects and food color recognition by chicks / Reconhecimento de cores de objetos e de alimento por pintos

The study of cognitive abilities of newborn broiler chicks using different colors of objects and foods allows to check the level of perception of the animal related to the environment in which the animal finds himself, to understand its ability to retain memory and learning, contributing for the recognition of objects that are around the animal. The objective of this research was to evaluate by preference tests, the ability of perception of broiler chicks in the recognition of objects and foods of different colors. The survey consisted in conditioning of 60 sexed broiler (30 males and 30 females chicks) one-day-old for three days with blue balls and red food colors chosen for having opposed chromaticities. After the conditioning phase, a preference test was performed, in which the animals were placed individually in the center of an arena test with four options: red food, blue food, red balls and blue balls. Latency to the first peck and the number of pecks, the number of sequential pecks the total time the bird in each compartment occupied and the first occupied slot were recorded. According to this study, it was observed that females had a shorter latency period to choose the first compartment to be occupied, remained for a longer period inside the compartments and interacted more with the food or object preference compared to males (Table 1). Chicks took less time for decisi

O artigo não apresenta resumo em português.

Objects and food color recognition by chicks / Reconhecimento de cores de objetos e de alimento por pintos

The study of cognitive abilities of newborn broiler chicks using different colors of objects and foods allows to check the level of perception of the animal related to the environment in which the animal finds himself, to understand its ability to retain memory and learning, contributing for the recognition of objects that are around the animal. The objective of this research was to evaluate by preference tests, the ability of perception of broiler chicks in the recognition of objects and foods of different colors. The survey consisted in conditioning of 60 sexed broiler (30 males and 30 females chicks) one-day-old for three days with blue balls and red food colors chosen for having opposed chromaticities. After the conditioning phase, a preference test was performed, in which the animals were placed individually in the center of an arena test with four options: red food, blue food, red balls and blue balls. Latency to the first peck and the number of pecks, the number of sequential pecks the total time the bird in each compartment occupied and the first occupied slot were recorded. According to this study, it was observed that females had a shorter latency period to choose the first compartment to be occupied, remained for a longer period inside the compartments and interacted more with the food or object preference compared to males (Table 1). Chicks took less time for decisi

O artigo não apresenta resumo em português.

Influence of technical training on human-animal interactions at milking / Influência do treinamento técnico sobre interações humano-animal na ordenha

Faced with the prominent developments in breeding dairy cattle systems in Brazil, it is observed that the aspects related to animal welfare (AW) and the human-animal relationship did not achieve the same breakthrough. Thus, actions are needed that may generate positive changes in human-animal relationship, which relates closely to the AW and productivity in dairy cows. Therefore, this work aimed to evaluate the human-animal interactions at milking and the influence of technical training on these interactions. The research was divided into four stages. The first step consisted in selecting of six dairy farms based on pasture in São Paulo State. The second step was the evaluation of milking and the action of workers through the proposed protocol by Hemsworth et al. (2002): moving the cows in the shed for milking line activities; forcing the cows in the milking position; coupling and uncoupling the liners and moving the cows out of the milking line. Tactile interactions of humans toward the cows were classified as positive (POS) or negative (NEG), which were considered positive interactions "patting", affection or support hand on the back, legs or flanks of the cow, whereas negative interactions included slaps , shoving, or blows with the hand or with objects of any type. In the third stage, it was realized the technical training on good practices for the AW with the workers of th

O artigo não apresenta resumo em português.

Vibrations and mechanical shocks in different roads during the transport of day-old chickes / Vibrações e choques mecânicos em diferentes estradas durante o transporte de pintos de um dia

The vibration and mechanical shocks that occur during the transport of chicks may act as a stressor of birds. The quality of roads also has serious impacts on load, because most vehicles are not designed to reduce vibration felt by the animals. The aim of this study was to evaluate the transport of day-old chicks on different roads, through vibration and shock of the trucks.  The research was conducted in a poultry integrator company located at state of São Paulo, through the monitoring of 11 shipments of chicks. The day-old chicken transport truck (approximately 8 x 2.50 m, 2.50 m high) was environmentally controlled, with three box stacks (left, right and center) spaced 0.7 m and two axis, with a capacity of 630 boxes of chicks, totaling an average of 63,000 chicks. The vibration levels reviews RMS X (vertical vibration), RMS Z (horizontal vibration) and RSS (general acceleration) and shocks on the dirt and asphalt roads were recorded using three triaxial accelerometers. The experimental design was completely randomized in an 11 x 2 factorial. Difference in vibration levels between dirt roads and asphalt, for RMS X, RMS Z and RSS, with the highest means were observed on the dirt road (P 0.05). However there was no statistical difference between the roads to the RMS Y (Table 1). This event can be attributed to the large irregularities and holes in dirt track. Generally thes

ês.

Quality of fertilized eggs exposed to simulated mechanical vibrations condition / Qualidade de ovos fertilizados expostos a condições simuladas de vibrações mecânicas

The fertile egg transport is a crucial issue in the Brazilian broiler aviculture chain. Therefore, many agents intrinsically connected to this process such as the mechanical vibrations, can jeopardize the integrity of this fragile load. Given to this threatening problem the aim of this research was to assess the quality of fertile eggs exposed to different simulated conditions of mechanical vibrations. A mechanical agitator was developed to reproduce the treatments of this study, which were formed by 2 vibration levels. An inferior (instantaneous acceleration, up to 5 m s-2) and a superior (instantaneous acceleration above 10 m/s2), in which they were applied in 2 exposition times, a minimum (60 minutes) and a maximum (180 minutes), making the treatments T1, T2, T3, T4. The assay was conducted in a random modeling in 4 complete blocks that represented the factorial repetitions 2 x 2 +1, with an additional treatment (control). In the total, 2016 eggs from the same batch of matrixes (Cobb-500) in the peak egg reproduction (32-35 weeks) were used. From these eggs, 1920 were exposed to the 4 factorial treatment vibrations (480 eggs per treatment), meanwhile, the remaining 96 were used as control treatment. Among the vibrated eggs, 96 per treatment were sampled in order to be analyzed. In addition, some factors were verified: the diameter and the egg yolk height (EYD and EYH), the d

O artigo não apresenta resumo em português.

The negative effects of mechanical vibrations on transport of fertile eggs / Os efeitos negativos das vibrações mecânicas no tranporte de ovos fertilizados

Mechanical vibrations resulted from transportation are mentioned to be a high hazardous issue of integrity and physiology found in biological systems. Fertile eggs that are transported from broiler farm to hatcheries are susceptible to harmful results, and it is still unknown all the possible effects in embryo development. Thus, the goal of this study was to evaluate the loss during hatching and in the quality of broiler chicks, after fertile eggs were exposed to simulated mechanical vibrations in different conditions. The experiment was developed in a commercial hatchery in Mogi-Mirim, São Paulo. Altogether, 1920 fertile eggs from Cobb-500 (31 to 34 weeks) were used. These eggs were exposed to vibrations during the transport in a mechanical simulator (Figure 1a). The assay was performed in a random modeling in blocks arranged in a factorial 2 x 2 + 1 with an additional treatment. The analyzed factors were determined by two vibration levels (lower with RSS 2.5 m/s2 and higher with RSS 7.5 m/s2), associated with two periods of exposition time (60 and 180 minutes). For the results, the answers from birth were analyzed using the hatching rate. The quality of broiler chicks obtained by the amount of first line chicks; and the total loss in the hatchery found in the summation of previous answers. Analyzes were done using a modeling of logistical regression, the effects of significan

O artigo não apresenta resumo em português.

Evaluation of thermal transport of day-old chicks / Avaliação térmica do transporte de pintos de um dia

The combining factors during initial handling might affect the broiler growth during the last week. Other factors might be considered, such as: fasting time, distance between hatchery and farm, vibration level, road quality, travel time, type of boxes and controlling environment inside the lorry. The aim of this work was to assess the thermal profile of truck with different levels of box placement during day-old chickens transport. An experiment was conducted through monitoring of 11 transport loads, with maximum capacity of 630 day-old chickens boxes, totalizing 63,000 animals. The day-old chicken transport truck (approximately 8 × 2.50 m, 2.50 m high) was environmentally controlled, with three box stacks (left, right and center) spaced 0.7 m. Air temperature, wind speed and humidity were controlled by sensors and electronic panel located in the truck cab. The set points for thermal conditions were: temperature between 23 and 25C and relative humidity between 60 and 70%. To characterize the environmental condition during transport, the following thermal variables were used: dry-bulb temperature, relative humidity and specific enthalpy, through data loggers (Onset, HOBO) programmed to record data at 10 minute intervals. Data was registered in two levels of the load (first rack and floor) where 17 data loggers were distributed throughout the truck. The experiment used a complet

O artigo não apresenta resumo em português.

Thermal stress related with mortality rates on broilers' preslaughter operations: a lairage time effect study

Concerning the reduction of preslaughter death losses, high temperature and relative humidity in the tropics are the major concerns regarding broiler survival prior slaughtering. However, the relationship between different lairage times under controlled environment and the thermal condition outside the holding area is still unclear. Thus, the aim of this study was to compare different intervals of lairage time with different environmental temperature and relationship with poultry mortality rates. A study was conducted in a commercial poultry abattoir in the State of Sao Paulo, Brazil, in the year of 2006. The historical data set from 13,937 trucks, about broiler mortality during preslaughter operations, was given by the abattoir. Factors that influence the welfare of birds were studied, such as lairage time in abattoir and hourly dry-bulb temperature. The statistical analysis was performed using the Double Generalized Linear Models. The lower incidence of death losses before arrival at the processing plant (approximately 13 dead birds per truck) was observed when the lairage time was between 1 to 3 hours, under high temperatures (above 22°C). This effect was more pronounced under critical (25-28°C) and lethal intervals (above 29°C) (12 and 13 dead birds per truck, respectively). In relation to lairage time, the reduction in mortality rates was more pronounced in the intervals up to 1 hour of lairage under climatized conditions, with a reduction of 3 dead birds per truck. It was concluded that thermal stress have negative influence for broilers welfare kept under preslaughter conditions and variations on mortality rate are strongly related with different lairage times.

No que diz respeito à redução das perdas por mortalidade pré-abate, as temperaturas e umidades relativas elevadas nos trópicos são as maiores preocupações quanto à sobrevivência de frangos de corte antes do abate. Entretanto, a relação entre diferentes tempos de espera em ambiente controlado e a condição térmica fora do galpão de espera ainda não está clara. Dessa forma, objetivou-se por meio deste trabalho comparar diferentes tempos de espera com diferentes temperaturas externas e a influência nas taxas de mortalidade de frangos de corte. O estudo foi conduzido em um abatedouro comercial de frangos de corte, situado no Estado de São Paulo, Brasil, durante o ano de 2006. Dados históricos de mortalidade de aves durante as operações pré-abate foram obtidos no abatedouro, provenientes de 13.937 caminhões transportadores de frangos de corte. Fatores que influenciam o bem estar das aves foram estudados, dentre eles, o tempo de espera no abatedouro e a temperatura horária do ambiente externo. A análise estatística foi realizada por meio dos Modelos Lineares Generalizados Duplos. A baixa incidência de mortes antes da chegada à linha de abate foi observada (aproximadamente 13 aves mortas por caminhão) quando o tempo de espera esteve entre 1 e 3 horas, sob altas temperaturas (acima de 22°C). Esse efeito foi mais evidente nas faixas crítica (25-28°C) e letal (acima de 29°C) (12 e 13 aves mortas por caminhão, respectivamente). Com relação ao tempo de espera, a redução da mortalidade foi mais pronunciada em intervalos acima de uma hora de espera, sob condições de espera climatizada. Conclui-se que o estresse térmico possui influência negativa para o bem-estar de frangos mantidos sob condição pré-abate e variações na taxa de mortalidade são fortemente relacionadas aos diferentes tempos de espera.

Thermal stress related with mortality rates on broilers' preslaughter operations: a lairage time effect study

Concerning the reduction of preslaughter death losses, high temperature and relative humidity in the tropics are the major concerns regarding broiler survival prior slaughtering. However, the relationship between different lairage times under controlled environment and the thermal condition outside the holding area is still unclear. Thus, the aim of this study was to compare different intervals of lairage time with different environmental temperature and relationship with poultry mortality rates. A study was conducted in a commercial poultry abattoir in the State of Sao Paulo, Brazil, in the year of 2006. The historical data set from 13,937 trucks, about broiler mortality during preslaughter operations, was given by the abattoir. Factors that influence the welfare of birds were studied, such as lairage time in abattoir and hourly dry-bulb temperature. The statistical analysis was performed using the Double Generalized Linear Models. The lower incidence of death losses before arrival at the processing plant (approximately 13 dead birds per truck) was observed when the lairage time was between 1 to 3 hours, under high temperatures (above 22°C). This effect was more pronounced under critical (25-28°C) and lethal intervals (above 29°C) (12 and 13 dead birds per truck, respectively). In relation to lairage time, the reduction in mortality rates was more pronounced in the intervals up to 1 hour of lairage under climatized conditions, with a reduction of 3 dead birds per truck. It was concluded that thermal stress have negative influence for broilers welfare kept under preslaughter conditions and variations on mortality rate are strongly related with different lairage times.

No que diz respeito à redução das perdas por mortalidade pré-abate, as temperaturas e umidades relativas elevadas nos trópicos são as maiores preocupações quanto à sobrevivência de frangos de corte antes do abate. Entretanto, a relação entre diferentes tempos de espera em ambiente controlado e a condição térmica fora do galpão de espera ainda não está clara. Dessa forma, objetivou-se por meio deste trabalho comparar diferentes tempos de espera com diferentes temperaturas externas e a influência nas taxas de mortalidade de frangos de corte. O estudo foi conduzido em um abatedouro comercial de frangos de corte, situado no Estado de São Paulo, Brasil, durante o ano de 2006. Dados históricos de mortalidade de aves durante as operações pré-abate foram obtidos no abatedouro, provenientes de 13.937 caminhões transportadores de frangos de corte. Fatores que influenciam o bem estar das aves foram estudados, dentre eles, o tempo de espera no abatedouro e a temperatura horária do ambiente externo. A análise estatística foi realizada por meio dos Modelos Lineares Generalizados Duplos. A baixa incidência de mortes antes da chegada à linha de abate foi observada (aproximadamente 13 aves mortas por caminhão) quando o tempo de espera esteve entre 1 e 3 horas, sob altas temperaturas (acima de 22°C). Esse efeito foi mais evidente nas faixas crítica (25-28°C) e letal (acima de 29°C) (12 e 13 aves mortas por caminhão, respectivamente). Com relação ao tempo de espera, a redução da mortalidade foi mais pronunciada em intervalos acima de uma hora de espera, sob condições de espera climatizada. Conclui-se que o estresse térmico possui influência negativa para o bem-estar de frangos mantidos sob condição pré-abate e variações na taxa de mortalidade são fortemente relacionadas aos diferentes tempos de espera.

Thermal stress related with mortality rates on broilers' preslaughter operations: a lairage time effect study

Concerning the reduction of preslaughter death losses, high temperature and relative humidity in the tropics are the major concerns regarding broiler survival prior slaughtering. However, the relationship between different lairage times under controlled environment and the thermal condition outside the holding area is still unclear. Thus, the aim of this study was to compare different intervals of lairage time with different environmental temperature and relationship with poultry mortality rates. A study was conducted in a commercial poultry abattoir in the State of Sao Paulo, Brazil, in the year of 2006. The historical data set from 13,937 trucks, about broiler mortality during preslaughter operations, was given by the abattoir. Factors that influence the welfare of birds were studied, such as lairage time in abattoir and hourly dry-bulb temperature. The statistical analysis was performed using the Double Generalized Linear Models. The lower incidence of death losses before arrival at the processing plant (approximately 13 dead birds per truck) was observed when the lairage time was between 1 to 3 hours, under high temperatures (above 22°C). This effect was more pronounced under critical (25-28°C) and lethal intervals (above 29°C) (12 and 13 dead birds per truck, respectively). In relation to lairage time, the reduction in mortality rates was more pronounced in the intervals up to 1 hour of lairage under climatized conditions, with a reduction of 3 dead birds per truck. It was concluded that thermal stress have negative influence for broilers welfare kept under preslaughter conditions and variations on mortality rate are strongly related with different lairage times.

No que diz respeito à redução das perdas por mortalidade pré-abate, as temperaturas e umidades relativas elevadas nos trópicos são as maiores preocupações quanto à sobrevivência de frangos de corte antes do abate. Entretanto, a relação entre diferentes tempos de espera em ambiente controlado e a condição térmica fora do galpão de espera ainda não está clara. Dessa forma, objetivou-se por meio deste trabalho comparar diferentes tempos de espera com diferentes temperaturas externas e a influência nas taxas de mortalidade de frangos de corte. O estudo foi conduzido em um abatedouro comercial de frangos de corte, situado no Estado de São Paulo, Brasil, durante o ano de 2006. Dados históricos de mortalidade de aves durante as operações pré-abate foram obtidos no abatedouro, provenientes de 13.937 caminhões transportadores de frangos de corte. Fatores que influenciam o bem estar das aves foram estudados, dentre eles, o tempo de espera no abatedouro e a temperatura horária do ambiente externo. A análise estatística foi realizada por meio dos Modelos Lineares Generalizados Duplos. A baixa incidência de mortes antes da chegada à linha de abate foi observada (aproximadamente 13 aves mortas por caminhão) quando o tempo de espera esteve entre 1 e 3 horas, sob altas temperaturas (acima de 22°C). Esse efeito foi mais evidente nas faixas crítica (25-28°C) e letal (acima de 29°C) (12 e 13 aves mortas por caminhão, respectivamente). Com relação ao tempo de espera, a redução da mortalidade foi mais pronunciada em intervalos acima de uma hora de espera, sob condições de espera climatizada. Conclui-se que o estresse térmico possui influência negativa para o bem-estar de frangos mantidos sob condição pré-abate e variações na taxa de mortalidade são fortemente relacionadas aos diferentes tempos de espera.

Sarcoplasmatic and myofibrillar protein changes caused by acute heat stress in broiler chicken

Acute heat stress (AHS) modifies the structure of myofibrils affecting functional properties of meat, mainly the water holding capacity. This experiment aimed to identify changes in proteolysis and migration between the myofibrillar and sarcoplasmatic fractions due to pre-slaughter AHS. Myofibrillar fragmentation index (MFI), SDS-PAGE, western blot of vinculin (WB) and shear force (SF) were determined. Six hundred broilers (Gallus gallus) were slaughtered in three different days (ST). In each ST, groups of ten animals were placed in transport crates and submitted to AHS (35ºC, 75 - 85% RH) for 2 hours. Simultaneously, the non-stressed broilers (NS) were kept in thermoneutral environment (22ºC, 83 ± 6.6% RH) within the crates in the same density. After slaughter, the breast muscles were kept refrigerated until the withdrawal of all samples (0, 1, 2, 6 and 24 hours after slaughter). Sampling within AHS and NS birds was collected according to lightness value (normal L* 49, and high > 51), except for determination of MFI and SF. The lightness was used later to perform SDS-PAGE and WB analyses. MFI kinetics showed that the fragmentation rate was superior in animals NS, indicating that AHS can harm proteolysis and rate of myofibrillar fragmentation. However, the extent of fragmentation did not change, as well as SF values. SDS-PAGE for Troponin fragments indicated a differentiated pattern between AHS and NS. The WB did not show alterations in vinculin fragmentation. Modifications in sarcoplasmatic fraction are observed in meat with high L*values, independent of environmental condition.

O estresse térmico agudo (ET) causa alterações na estrutura das miofibrilas, afetando propriedades funcionais da carne, principalmente a capacidade de retenção de água. Identificaram-se mudanças na proteólise e migração entre as frações miofibrilar e sarcoplasmática, decorrentes do ET pré-abate, através do índice de fragmentação miofibrilar (MFI), SDS-PAGE para troponina (SDS), imunodetecção de vinculina (IV) e força de cisalhamento (FC). Seiscentos frangos (Gallus gallus) foram abatidos em três dias diferentes (DA). Em cada DA os animais foram colocados em caixas de transporte (10 aves/caixa) e submetidos a ET (35ºC, 75 - 85% UR)por 2 horas. Simultaneamente, o outro grupo de animais (NET) foi mantido em caixas em condição termoneutra (22ºC, 83 ± 6,6% UR) pelo mesmo período de tempo. Após o abate o músculo do peito foi coletado e mantido refrigerado, até a retirada de todas as amostras (0, 1, 2, 6 e 24 horas pós-abate). O valor de luminosidade (L* 49, normal e > 51, alto), foi o parâmetro utilizado na amostragem para SDS e IV. A cinética do MFI demonstrou que a taxa de fragmentação foi superior nos animais NET, indicando que o estresse térmico pode prejudicar o processo de proteólise. Entretanto, a extensão da fragmentação não variou, bem como os valores de FC. No SDS ocorreram padrões diferenciados de fragmentação entre aves ET e NET. Modificações na fração sarcoplasmática foram observadas em amostras com L*, independentemente da condição ambiental.

Sarcoplasmatic and myofibrillar protein changes caused by acute heat stress in broiler chicken

Acute heat stress (AHS) modifies the structure of myofibrils affecting functional properties of meat, mainly the water holding capacity. This experiment aimed to identify changes in proteolysis and migration between the myofibrillar and sarcoplasmatic fractions due to pre-slaughter AHS. Myofibrillar fragmentation index (MFI), SDS-PAGE, western blot of vinculin (WB) and shear force (SF) were determined. Six hundred broilers (Gallus gallus) were slaughtered in three different days (ST). In each ST, groups of ten animals were placed in transport crates and submitted to AHS (35ºC, 75 - 85% RH) for 2 hours. Simultaneously, the non-stressed broilers (NS) were kept in thermoneutral environment (22ºC, 83 ± 6.6% RH) within the crates in the same density. After slaughter, the breast muscles were kept refrigerated until the withdrawal of all samples (0, 1, 2, 6 and 24 hours after slaughter). Sampling within AHS and NS birds was collected according to lightness value (normal L* 49, and high > 51), except for determination of MFI and SF. The lightness was used later to perform SDS-PAGE and WB analyses. MFI kinetics showed that the fragmentation rate was superior in animals NS, indicating that AHS can harm proteolysis and rate of myofibrillar fragmentation. However, the extent of fragmentation did not change, as well as SF values. SDS-PAGE for Troponin fragments indicated a differentiated pattern between AHS and NS. The WB did not show alterations in vinculin fragmentation. Modifications in sarcoplasmatic fraction are observed in meat with high L*values, independent of environmental condition.

O estresse térmico agudo (ET) causa alterações na estrutura das miofibrilas, afetando propriedades funcionais da carne, principalmente a capacidade de retenção de água. Identificaram-se mudanças na proteólise e migração entre as frações miofibrilar e sarcoplasmática, decorrentes do ET pré-abate, através do índice de fragmentação miofibrilar (MFI), SDS-PAGE para troponina (SDS), imunodetecção de vinculina (IV) e força de cisalhamento (FC). Seiscentos frangos (Gallus gallus) foram abatidos em três dias diferentes (DA). Em cada DA os animais foram colocados em caixas de transporte (10 aves/caixa) e submetidos a ET (35ºC, 75 - 85% UR)por 2 horas. Simultaneamente, o outro grupo de animais (NET) foi mantido em caixas em condição termoneutra (22ºC, 83 ± 6,6% UR) pelo mesmo período de tempo. Após o abate o músculo do peito foi coletado e mantido refrigerado, até a retirada de todas as amostras (0, 1, 2, 6 e 24 horas pós-abate). O valor de luminosidade (L* 49, normal e > 51, alto), foi o parâmetro utilizado na amostragem para SDS e IV. A cinética do MFI demonstrou que a taxa de fragmentação foi superior nos animais NET, indicando que o estresse térmico pode prejudicar o processo de proteólise. Entretanto, a extensão da fragmentação não variou, bem como os valores de FC. No SDS ocorreram padrões diferenciados de fragmentação entre aves ET e NET. Modificações na fração sarcoplasmática foram observadas em amostras com L*, independentemente da condição ambiental.

Thermal conditioned of freestall facilities resting area and its consequences on productive and physiological responses in dairy cows / Eficiência de sistemas de climatização na área de descanso em instalações do tipo freestall e sua influência nas respostas produtivas e fisiológicas de vacas em lactação

This work aimed to evaluate the efficiency of thermal conditioned in free-stall facilities and its consequences on productive and physiological responses in dairy cows. Experimental period was 28 consecutive days of November/2003. Fifteen dairy multiple cows with average milk production of 20kg/day were used. Treatments were: non-fan (NF); fan (F) and fan + misting (FM) directioned to animal bedding. Dry bulb temperature (DBT) and air relative humidity (RH) were measured every 15 minutes through a period of 24 hours inside and outside of facilities. Milking was realized at 1:00am; 9:00am and 5:00pm and date were collected. Animals were fed twice a day (10:00am and 3:00pm) and amounts of offered and rejected feed were daily registered. Physiological data such, as respiratory frequency (RF); rectal temperature (RT) and skin temperature (ST), were taken at 9:00am, 11:00am, 1:00pm, 3:00pm and 5:00pm. The RH was higher in V0 (61.8%) and VN (61.8%) treatments than in V (60.3%). The THI was higher in V (75.0) than in V0 (74.5) and VN (74.3) treatments. Related to physiological parameters, lactating cows of V0 treatment had lower rectal temperature at 11:00am (37.9ºC); 01:00pm (38.2ºC) and 05:00pm (38.2ºC). Respiratory frequencies (58; 55 e 58 mov/min, respectively, to V0; V e VN), white surface temperature (35.4ºC; 33.4ºC and 35.2ºC respectively, to V0; V and VN) and black surface tem

O trabalho teve como objetivo avaliar a eficiência de sistemas de climatização na área de descanso em instalação do tipo freestall e seus reflexos nas repostas produtivas e fisiológicas de vacas em lactação. O período experimental teve duração de 28 dias consecutivos do mês de novembro de 2003. Foram utilizadas 15 vacas em lactação, pluríparas, com produção média de 20kg de leite/dia. Os tratamentos adotados foram: ausência de ventilação (V0), ventilação (V) e ventilação + nebulização (VN) posicionados sobre a cama dos animais. A temperatura do bulbo seco (TBS) e a umidade relativa do ar (UR) foram mensuradas a cada 15 minutos ao longo das 24 horas no interior da instalação e no ambiente externo. A ordenha foi realizada à 1, às 9 e às 17 horas, e as produções diárias registradas. A alimentação era fornecida duas vezes ao dia (10 e 16 horas) e a quantidade de alimento oferecido e das sobras, foi registrada diariamente. As medidas fisiológicas, como freqüência respiratória (FR), temperatura retal (TR) e temperatura da pele (TP) de cinco animais em cada tratamento foram realizadas às 9, 11, 13, 15 e 17 horas. A UR mostrouse mais elevada nos tratamentos V0 (61,8%) e VN (61,8%) quando comparada ao tratamento V (60,3%). O ITU mostrou-se mais elevado em V (75,0), quando comparado ao tratamento V0 (74,5) e VN (74,3). Para as variáveis fisiológicas, verificou-se que as vacas em lactação

Thermal conditioned of freestall facilities resting area and its consequences on productive and physiological responses in dairy cows / Eficiência de sistemas de climatização na área de descanso em instalações do tipo freestall e sua influência nas respostas produtivas e fisiológicas de vacas em lactação

This work aimed to evaluate the efficiency of thermal conditioned in free-stall facilities and its consequences on productive and physiological responses in dairy cows. Experimental period was 28 consecutive days of November/2003. Fifteen dairy multiple cows with average milk production of 20kg/day were used. Treatments were: non-fan (NF); fan (F) and fan + misting (FM) directioned to animal bedding. Dry bulb temperature (DBT) and air relative humidity (RH) were measured every 15 minutes through a period of 24 hours inside and outside of facilities. Milking was realized at 1:00am; 9:00am and 5:00pm and date were collected. Animals were fed twice a day (10:00am and 3:00pm) and amounts of offered and rejected feed were daily registered. Physiological data such, as respiratory frequency (RF); rectal temperature (RT) and skin temperature (ST), were taken at 9:00am, 11:00am, 1:00pm, 3:00pm and 5:00pm. The RH was higher in V0 (61.8%) and VN (61.8%) treatments than in V (60.3%). The THI was higher in V (75.0) than in V0 (74.5) and VN (74.3) treatments. Related to physiological parameters, lactating cows of V0 treatment had lower rectal temperature at 11:00am (37.9ºC); 01:00pm (38.2ºC) and 05:00pm (38.2ºC). Respiratory frequencies (58; 55 e 58 mov/min, respectively, to V0; V e VN), white surface temperature (35.4ºC; 33.4ºC and 35.2ºC respectively, to V0; V and VN) and black surface tem

O trabalho teve como objetivo avaliar a eficiência de sistemas de climatização na área de descanso em instalação do tipo freestall e seus reflexos nas repostas produtivas e fisiológicas de vacas em lactação. O período experimental teve duração de 28 dias consecutivos do mês de novembro de 2003. Foram utilizadas 15 vacas em lactação, pluríparas, com produção média de 20kg de leite/dia. Os tratamentos adotados foram: ausência de ventilação (V0), ventilação (V) e ventilação + nebulização (VN) posicionados sobre a cama dos animais. A temperatura do bulbo seco (TBS) e a umidade relativa do ar (UR) foram mensuradas a cada 15 minutos ao longo das 24 horas no interior da instalação e no ambiente externo. A ordenha foi realizada à 1, às 9 e às 17 horas, e as produções diárias registradas. A alimentação era fornecida duas vezes ao dia (10 e 16 horas) e a quantidade de alimento oferecido e das sobras, foi registrada diariamente. As medidas fisiológicas, como freqüência respiratória (FR), temperatura retal (TR) e temperatura da pele (TP) de cinco animais em cada tratamento foram realizadas às 9, 11, 13, 15 e 17 horas. A UR mostrouse mais elevada nos tratamentos V0 (61,8%) e VN (61,8%) quando comparada ao tratamento V (60,3%). O ITU mostrou-se mais elevado em V (75,0), quando comparado ao tratamento V0 (74,5) e VN (74,3). Para as variáveis fisiológicas, verificou-se que as vacas em lactação