Petr Chloupek

Changes in selected biochemical indices related to transport of broilers to slaughterhouse under different ambient temperatures

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.

Time course changes in selected biochemical indices of broilers in response to pretransport handling

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.

Changes in Selected Biochemical Indices Resulting from Various Pre-sampling Handling Techniques in Broilers

BackgroundSince it is not yet clear whether it is possible to satisfactorily avoid sampling-induced stress interference in poultry, more studies on the pattern of physiological response and detailed quantification of stress connected with the first few minutes of capture and pre-sampling handling in poultry are required. This study focused on detection of changes in the corticosterone level and concentrations of other selected biochemical parameters in broilers handled in two different manners during blood sampling (involving catching, carrying, restraint, and blood collection itself) that lasted for various time periods within the interval 30-180 seconds.MethodsStress effects of pre-sampling handling were studied in a group (n = 144) of unsexed ROSS 308 broiler chickens aged 42 d. Handling (catching, carrying, restraint, and blood sampling itself) was carried out in a gentle (caught, held and carried carefully in an upright position) or rough (caught by the leg, held and carried with lack of care in inverted position) manner and lasted for 30 s, 60 s, 90 s, 120 s, 150 s, and 180 s. Plasma corticosterone, albumin, glucose, cholesterol, lactate, triglycerides and total protein were measured in order to assess the stress-induced changes to these biochemical indices following handling in the first few minutes of capture.ResultsPre-sampling handling in a rough manner resulted in considerably higher plasma concentrations of all biochemical indices monitored when compared with gentle handling. Concentrations of plasma corticosterone after 150 and 180 s of handling were considerably higher (P < 0.01) than concentrations after 30-120 s of handling regardless of handling technique. Concentrations of plasma lactate were also increased by prolonged handling duration. Handling for 90-180 seconds resulted in a highly significant elevation of lactate concentration in comparison with 30 s handling regardless of handling technique. Similarly to corticosterone concentrations, a strong positive correlation was found between plasma lactate and duration of pre-sampling handling. Other biochemical indices monitored did not show any correlation pattern in connection with duration of pre-sampling handling.ConclusionsThese results indicate that the pre-sampling procedure may be a considerably stressful procedure for broilers, particularly when carried out with lack of care and exceeding 120 seconds.

The effects of chronic intermittent noise exposure on broiler chicken performance

Effects of different noise levels (70 or 80 dB) that broilers were exposed to during the entire fattening period and also the effect of the timing of the first exposure to intermittent noise in the course of fattening (day 1 vs. day 7) were monitored. After 7 days of exposure to intermittent noise, experimental chickens already showed a significant decrease in live body weight in comparison with the control group. The difference between the group exposed to intermittent noise at 70 dB and the group exposed to 80 dB levels was not statistically significant, although the mean live body weight of broilers in the latter was lower during the entire fattening period. The chickens exposed to intermittent noise from day 1 of age showed lower mean live weight throughout the fattening period compared to chickens exposed to the same level of intermittent noise only from day 7 of age, although at the end of fattening the difference was statistically significant only in chickens exposed to the higher level of intermittent noise (80 dB).

Transport losses in finisher pigs: impact of transport distance and season of the year

Objective The death of animals during transport for slaughter is a major factor indicating the level of welfare in transported animals. The aim of this study was to assess mortality related to the commercial transport of finisher pigs for slaughter in the Czech Republic. Methods The inspectors of the State Veterinary Administration of the Czech Republic recorded the numbers of finisher pigs transported to processing plants in the Czech Republic for slaughter and the mortality in these pigs in relation to transport in the period from 2009 to 2014. Results Our results show that the likelihood of death losses in transported pigs increases with increasing transport distance. The transport-related mortality ranged from 0.049% in pigs transported for distances below 50 km to 0.145% in pigs transported for distances exceeding 300 km. The impact of external air temperature on the transport-related mortality found in our study clearly shows that current transport practices fail to ensure the welfare of pigs transported under other than moderate weather. Particularly cold temperatures below −2°C were associated with increased death losses in winter transport. Conclusion Despite a decreasing trend in the mortality of finisher pigs transported for slaughter in Europe, our study suggests that current transport conditions are not efficient at ensuring the welfare of pigs during transport for longer distances and the protection of pigs against the negative impact of extreme ambient temperatures. Further research should focus on developing practical guidelines to improve the welfare of pigs in transit accordingly.