No abstract

The effect of transport distance on selected biochemical parameters (corticosterone, uric acid, triglycerides, total protein, glucose, and lactate) under various ambient temperatures was monitored in a group of unsexed Ross 308 broilers aged 42 d. Broilers were transported to the slaughterhouse over 3 different travel distances (10, 70, and 130 km). They were sampled before and after each transportation in 3 various periods with different ambient temperatures (-5 to +5°C, 10 to 20°C, and 25 to 35°C), which approximately correspond to temperature conditions during transport in individual seasons of the year (winter, fall, summer). The changes in biochemical parameters were specific in their dependence on the travel distance and the ambient temperature under which the broilers were transported. The highest corticosterone concentration was found in broilers before transport (i.e., immediately after catching, crating, and loading) at all ambient temperatures. The concentration of corticosterone was higher at winter temperatures than at summer and fall temperatures. Triglycerides decreased with travel distance, although this effect was detected under summer temperatures only. The concentration of total protein was higher only after 10 km of transport and then it decreased with travel distance at all monitored ambient temperatures. A highly significant decrease (P < 0.01) in the glucose level of broilers was observed after 130 km of transport when compared with broilers before transport at fall and winter temperatures. The effect of travel distance on lactate concentrations was the same at all monitored ambient temperatures, with the lactate level decreasing with travel distance. The results obtained indicate that pretransport handling procedures (catching, crating, and loading) may be more stressful for broilers than the transport itself. To improve broiler meat quality, it is necessary to meet the need for broilers to recover before being slaughtered. With regard to different seasons of the year, we can assume that transport under conditions of low ambient temperatures in winter represents a more stressful event than transport during fall and summer.

Two experiments were conducted to assess the stress response of broilers to catching and pretransport handling followed by different periods of crating. The short-term changes in selected biochemical indices were monitored at 1-min intervals within 10 min of crating after the catching and handling of broilers (experiment 1). These indices were further monitored at 15-min intervals for 2 h of crating after the catching and handling of broilers (experiment 2). Increased (P < 0.001) corticosterone concentrations were observed immediately after the broilers were caught, handled, and placed in crates. They continued to increase until 7 min after crating and then slowly decreased, but even at 120 min after handling, corticosterone concentrations were higher (P < 0.001) in crated broilers than in control broilers. In addition, lactate concentrations increased (P < 0.001) immediately in comparison with those of broilers with no additional handling except for catching and blood sampling, but 15 min later, the lactate concentrations had decreased to the precrating level. Lactate dehydrogenase concentrations increased (P = 0.042) 30 min after crating and continued to increase for the rest of the monitored period. A decreased level of cholesterol (P = 0.017) and increased concentration of uric acid (P = 0.041) were found 1 min after crating. The decrease in cholesterol was visible up to 9 min after crating; it then returned to its original value except for the period from 75 to 90 min after crating, when a decrease (P < 0.05) was again detected. Higher (P < 0.01) concentrations of uric acid were found continuously from 4 to 75 min after crating. Glucose concentrations were increased (P = 0.017) 2 min after crating, but the stress-induced increase was not consistent over the course of the next few minutes after crating. Glucose concentrations were not different from those of control broilers from 10 to 120 min after crating, although they showed a decreasing pattern. A decrease (P = 0.031) in triglyceride concentrations was detected 75 min after crating.

No abstract

The effects of transportation to the slaughterhouse (catching, crating, loading, transport) at various ambient temperatures on selected biochemical indices were monitored in a group of unsexed ROSS 308 broiler chickens aged 42 days. The broilers were sampled at three different sampling times (prior to loading, after loading, and after 70 km transport) at three different ambient temperatures (-5 to +5 °C, 10 to 20 °C, 25 to 35 °C). Corticosterone contents in broilers after loading and after transport were significantly higher (P < 0.01) than before loading. The highest corticosterone concentration was found in broilers that were handled (loaded and transported) at lower temperatures (-5 °C to +5 °C) and this value was significantly (P < 0.01) lower than in broilers handled under both other monitored temperature ranges. The results of this study prove that the stress-inducing procedure to which commercial broilers are exposed in connection with transport to the slaughterhouse induces strong changes in selected biochemical indices, and that these changes are highest in winter months at a lower ambient temperature.