Effects Of Pre-Slaughter Stress On Productivity And Welfare Of Broiler

After a long time calm life, pre-slaughter stress will affect the broiler’s quite life, meat quality and welfare. In this study, we simulated the pre-slaughter stress, such as feed withdrawal, transport, lariage and shackling. We evaluated the broilers’ production performance indicators, blood indicators, behavioral indicators and indicators of welfare. At last, in our results we would find a best time threshold for every process and a best feeding method (floor group and free range group) to against pre-slaughter stress. Experiment1Effects of different feed withdrawal time on productivity and welfare of broilerExperiment design:50healthy Avian broilers of53days (cock and hen evenly divided) from each feeding method were randomly allocated into five treatments which including two replicates per treatment, five broilers per replicate. Treatment groups were feed deprived0h,4h,6h,8h,10h respectively. We killed the treatment groups’broilers in order to determine meat quality, body weight loss, contamination propensity scale and metabolic index of broilers.Result:1)Effects of feed withdrawal time on broilers:The4h group of free range group boilers’ pH1were significantly higher than6h and10h groups(p<0.05); The10h group of free range group boilers’ drip losses were significantly higher than0h、4h、6h groups(p<0.05).The6h,8h,10h groups of free range group and floor group boilers’ L*value were were significantly higher than0h、4h groups(p<0.05). The10h groups of free range group and floor group boilers’the body weight losses were were significantly higher than0h,4h,6h groups(p<0.05). The Oh groups of free range group and floor group boilers’the lactate content were significantly higher than10h groups(p<0.05).The0h groups of feed withdrawal broilers prone to carcass contamination.2)Effects of rearing methods on broilers:The L*of floor group group broilers were significantly higher than free range group broilers(p<0.05), the gizzard contents and whole gut contents of free range group broilers were significantly higher than floor group broilers(p<0.05). In our study, no other significant effects of rearing methods on broilers were noticed(p>0.05).Conclusion:The broiler of floor group and free range group should be feed deprived6h before transportation. Experiment2Effects of different transport time on productivity and welfare of broiler Experiment design:40healthy Avian broilers of54days(cock and hen evenly divided) from each feeding method were randomly allocated into four treatments which including two replicates per treatment, five broilers per replicate. Treatment groups were transported2h,3h,4h,5h respectively. We killed the treatment groups’ broilers in order to determine meat quality,body weight loss, pre-slaughter struggle behavior and lairage time behavior.Result:1) Effects of transport time on broilers:The4h、5h group of floor group broilers’L*and drip losses were significantly higher than2h group(p<0.05). The5h group of free range group broilers’ L*were significantly higher than2h group(p<0.05);The2h group of free range group broilers’ standing behavior, walking behavior, nonnutritive pecking behavior were significantly more than4h and5h group(p<0.05), but lying behavior were significantly less than3h,4h and5h group(p<0.05). Transport time had no significantly effects on body weight loss and pre-slaughter struggle behavior of broilers(p>0.05).2) Effects of rearing methods on broilers:The standing behavior, walking behavior, preening behavior, foraging behavior nonnutritive pecking behavior of free range group broilers were significantly more than floor group broilers(p<0.05), but lying behavior were significantly less than floor group broilers(p<0.05). Rearing methods had no significantly effects on body weight loss, meat quality and pre-slaughter struggle behavior of broilers(p>0.05).Conclusion:Maximum transport time should not exceed3h for floor group and free range group broilers. Experiment3Effects of different lairage time on productivity and welfare of broilerExperiment design:50healthy Avian broilers of55days (cock and hen evenly divided) from each feeding method were randomly allocated into five treatments which including two replicates per treatment, five broilers per replicate.Treatment groups’ broilers rested Omin,30min,60min,90min,120min respectively. We killed the treatment groups’ broilers in order to determine meat quality, body weight loss, pre-slaughter struggle behavior and deep-body temperature.Result:1) Effects of lariage time on broilers:The Omin group of floor group broilers’pH1were significantly lower than120min group(p<0.05);The Omin,30min and60min groups of floor group broilers’drip losses were significantly higher than120min group(p<0.05);The0min,90min groups of floor group broilers’ TDWF (total duration of wing flapping) were significantly longer than30min and120min groups(p<0.05). The Omin group of free range group broilers’pH2were significantly lower than30min group(p<0.05); The0min,30min group of free range group broilers’ shear force were significantly higher than60min group(p<0.05);The Omin group of free range group broilers’ TDWF (total duration of wing flapping) were significantly longer than60min group(p<0.05). Lariage time had no significantly effects on body weight loss and deep-body temperature of broilers(p>0.05).2) Effects of rearing methods on broilers:The drip losses and L*of floor group broilers were significantly higher than free range group broilers(p<0.05), but TDWF and the vocalisations were significantly lower than free range group broilers(p<0.05). Rearing methods had no significantly effects on body weight loss and deep-body temperature of broilers(p>0.05).Conclusion:Floor group broilers’ pre-slaughter lariage time should be90min and free range group broilers’pre-slaughter lariage time should be60min. Experiment4Effects of different shacking time on productivity and welfare of broilerExperiment design:50healthy Avian broilers of56days (cock and hen evenly divided) from each feeding method were randomly allocated into five treatments which including two replicates per treatment, five broilers per replicate. Then the treatment groups’broilers and shackled0s,30s,60s,90s,120s respectively. We killed the treatment groups’ broilers in order to determine meat quality, pre-slaughter struggle behavior and metabolic index of broilers.Result:1) Effects of shackling time on broilers:The60s,90s and120s groups of floor group broilers’ pH2were significantly lower than30s group(p<0.05);The90s group of floor group broilers’ drip losses were significantly higher than0s,30s groups(p<0.05); The120s group of floor group broilers’shear force were significantly higher than0s group(p<0.05). The120s group of free range group broilers’ pH2were significantly lower than0s,30s groups(p<0.05);The30s group of free range group broilers’ L*were significantly higher than120s group(p<0.05);The30s,120s groups of free range group broilers’glucose content were significantly higher than0s group(p<0.05).Shackling time had no significantly effects on pre-slaughter struggle behavior of broiler(p>0.05).2) Effects of rearing methods on broilers:The pH2of floor group broilers were significantly higher than free range group broilers(p<0.05). Rearing methods had no significantly effects on pre-slaughter struggle behavior and metabolic index of broilers(p>0.05).Conclusion:The best shackling time for floor group and free range group broilers should be12-30s.