Rearing and handling injuries in broiler chickens and risk factors for wing injuries during loading

Abstract

Some injuries to broilers occur during rearing, but most injuries occur during handling before slaughter. Records provided by a processing plant for loads transported over a 19-month period during 2009 and 2010 were examined. The median percentage of wing injuries per load was 5.7%; while injuries to the legs, breast or shoulders were all less than 1% per load. Risk factors for wing injuries were examined by considering the data from each load by handling event (i.e. loads originating from the same producer on the same date). A multilevel model with three levels: producer (n=86), handling event (n=1694) and load (n=4219) was fitted. The final model included: weight, sex, season, catching team, time of day at which loading began, speed of loading, and an interaction between speed of loading and time of day. Factors that reduced the risk of wing injuries were loading lighter birds, loads containing only cockerels and loading in the fall. The predicted percentage of wing injuries was relatively constant for slower loading speeds but was increased significantly when faster loading speeds were adopted during daytime (0700 to 1700 h). Identification of these risk factors can be used to adjust loading practices.

Comparison of the Automatic and Manual Broiler Pre-Slaughter Chain Based on Trailer Microclimate during Transportation and Its Effect on m. pectoralis major

“…Under optimal conditions, broilers should be exposed to a temperature in the so-called thermoneutral zone during transport. The results of our study do confirm previous research by Webster et al [27], in which the optimal thermal zone is 8-18 • C. In contrast to the earlier findings of Meltzer [28], these results suggest an optimal thermal zone from 24 to 28.5 • C. Temperature fluctuations and relative humidity may be a particular problem causing higher mortality and frequent injuries of transported broilers [7,9,[29][30][31].…”

Welfare of domestic birds and rabbits transported in containers

“…Recent bruising appears red; between 12 and 24 h after trauma, the bruise is often dark red to purple. Bruising that occurs during rearing can potentially be identified by a green colouration that occurs 24–48 h after trauma (Cockram et al., 2020). The bruises are difficult to see on the live animals but become more visible after plucking the carcass (feather removal during the slaughtering process).…”

Welfare of broilers on farm

“…Recent bruising appears red; between 12 and 24 h after trauma, the breast bruises often become dark red to purple, whereas leg and wing bruises become lighter. Bruising that occurs during rearing can potentially be identified by a green colouration that occurs 24–48 h after trauma (Cockram et al., 2020 ). Interpretation The more physical trauma to the chicken, the more bruises.…”