RESUMO Práticas inadequadas de manejo antes do abate podem comprometer o bem-estar animal e a qualidade da carne suína. Este estudo visou avaliar os efeitos do período de transporte (TT), período de descarga (TD), e período de pré-abate (TE) nos indicadores termofisiológicos animais e no pH da carne suína, utilizando uma abordagem multivariada. Este estudo foi realizado num matadouro localizado em Aquiraz, Ceará, Brasil. Um total de 60 suínos mestiços com 107 ± 5 kg de peso corporal foram distribuídos em três grupos experimentais: grupo A (TT = 180 min, TD ≤ 10 min, e TE = 24 horas), grupo B (TT = 60 min, TD ≤ 15 min, e TE = 18 horas), e grupo C (TT = 45 min, TD ≤ 5 min, e TE = 24 horas). A análise discriminante canônica foi implementada e as diferenças entre tratamentos são representadas graficamente. Os dois primeiros componentes foram responsáveis por 97% dos tratamentos. A análise discriminante mostrou que o grupo C apresentou diferenças multivariadas em relação aos outros, particularmente com temperatura retal elevada antes do abate (38,4 ± 0,23 °C) e frequência respiratória (131 ± 7,0 respirações min-1) e temperatura retal (39,7 ± 0,18 °C) à chegada ao matadouro. O período de transporte (TT), período de descarga (TD) e o stress térmico das instalações influenciaram variáveis fisiológicas, tais como a temperatura retal e a frequência respiratória. Além disso, as variáveis de estresse fisiológico também favoreceram cortes com pH básico, resultando em perda de qualidade.

ABSTRACT Inadequate pre-slaughter handling practices may compromise animal welfare and pork quality. This study aimed to evaluate the effects of transport period (TT), unloading period (UT), and pre-slaughtering period (WT) on animal thermophysiological indicators and pork pH using a multivariate approach. This study was conducted in a slaughterhouse located in Aquiraz, Ceará state, Brazil. A total of 60 mestizo pigs with 107 ± 5 kg body weight were distributed into three experimental groups: group A (TT = 180 min, UT ≤ 10 min, and WT = 24 hours), group B (TT = 60 min, UT ≤ 15 min, and WT = 18 hours), and group C (TT = 45 min, UT ≤ 5 min, and WT = 24 hours). Canonical discriminant analysis was implemented and the differences between treatments are represented graphically. The first two components accounted for 97% treatments. The discriminant analysis showed that group C presented multivariate differences in relation to others, particularly with high rectal temperature before slaughter (38.4 ± 0.23 °C) and respiratory rate (131 ± 7.0 breaths min-1) and rectal temperature (39.7 ± 0.18 °C) upon arrival at the slaughterhouse. Transport period (TT), unloading period (UT), and thermal stress of the facilities influenced physiological variables, such as rectal temperature and respiratory rate. Furthermore, the physiological stress variables also favored cuts with basic pH, resulting in quality loss.

ABSTRACT The characterisation of ventilation during the transport of broilers is essential to identify and solve problems related to the microclimate of the load. This study aimed to evaluate the ventilation patterns in alternative load layouts, i.e., with a central span or an air corridor, used in Brazil. Computational fluid dynamics simulations and wind tunnel tests were performed on virtual models and small-scale prototypes, respectively. The results showed that the load layout with a "central span" promoted positive ventilation patterns and increased wind circulation between the crates. However, it reduces the load transport capacity by approximately 20% (70 fewer crates), increasing the number of journeys. Therefore, the modification of the layout can optimise ventilation throughout the load; however, it becomes necessary to reduce the number of crates stacked on the truck, which is not feasible for the commercial transport of broilers because it makes it more onerous.

ABSTRACT This study evaluates the dynamics of heat zones in the load and its relationship with the stress of pigs during transport. Four journeys of 170 km were monitored, recording the physiological variables of 192 animals (48 per journey), namely rectal temperature (RT), body temperature (BT), respiratory rate (RR), blood lactate concentrations and salivary cortisol. Heat zones and ventilation patterns were characterized by the spatial variability of the enthalpy and the Computational Fluid Dynamics of the load. The formation of a thermal core was observed in the frontal region of the load, which extended through the lower (LD) and upper (UD) decks. Pigs transported in the LD had higher means of RR (UD = 89 and LD = 94 breaths/min), and salivary cortisol (UD = 33.84 and LD = 34.92 ng/mL). The pigs transported in the UD presented the highest mean BT (UD = 38.9 and LD = 38.1 °C) and lactate (UD = 61.63 and LD = 58.26 mg/dL). Pigs transported in the LD of the load were more susceptible to thermal stress, while pigs transported in the UD showed greater physical stress and muscle exhaustion.

ABSTRACT The objective of this study was to evaluate the reactivity of the pupillary area (PA) as a non-invasive method for diagnosing stress in piglets submitted to transport. A total of 10 journeys were monitored and grouped according to the transport distance (15 and 75 km). Were sampled 360 piglets (25±3.8 kg) to measure the PA, body temperature (BT), and serum concentrations of cortisol and creatine kinase (CK). The micrometeorological characterization of the load was performed using enthalpy comfort index (ECI). It was possible to identify an increase of 19.32% (+18.91 mm2; P< 0.001) in PA of piglets transported in shorter journeys (15 km), as well as the highest mean values of BT (+ 1.24 °C; P< 0.001), cortisol (+ 2.37 ng/mL; P< 0.001) and CK (+ 379 U/L; P= 0.025). In this study, high correlations of PA were observed with r = 0.922, 0.900, 0.842 and 0.829 ( P< 0.05) for cortisol and CK, BT and ECI of trailer, respectively. In conclusion, we state that PA reactivity is a physiological response for the diagnosis of stress of piglets transported. Further research will refine this technique in order to make this non-invasive acquisition method more practical and adaptable to different transport conditions.

ABSTRACT The characterization of ventilation during the transport of broiler chickens is essential for identifying and characterizing the potential problems of a convective heat flow and its effects on the welfare and the health and production conditions of the chickens. The objective of this study was to evaluate the ventilation patterns in two layout models of a live transport load: conventional (LC) and alternative (LA) with spacers placed between the chicken transport crates. Computational fluid dynamics (CFD) simulations and wind tunnel tests were performed using small scale models. The results showed that the use of spacers between crates (LA model) modified the ventilation patterns and increased the wind circulation between crates. However, wind tunnel tests simulating a density of eight birds/crate were inconclusive because the ventilation was below the sensitivity of the measuring devices used (0.001 m/s). It can be concluded that the use of spacers between the transport crates can modify the ventilation patterns within the load and increase the air circulation between the crates. However, the internal ventilation within the crates has not changed, suggesting the need for studies on the aerodynamics of a transport crate for poultry use.