The welfare impacts of mechanical and manual broiler catching and of circumstances at loading under field conditions

Abstract

Loading of broilers for transport to the processing plant poses a notable injury risk for broilers. Therefore, the poultry industry has developed mechanical methods as alternatives to manual loading methods. Our objective in the present study was to compare manual loading ( MAN ) of broilers with the mechanical loading ( MECH ). We assessed the injuries of broilers of 12 MAN and 12 MECH flocks on-farm before and immediately after loading, documented the numbers of broilers dead on arrival reported by the processing plant, and assessed the circumstances at loading. A smaller number of broilers with a hematoma (≥0.5 cm in diameter) on the wing were observed after MAN compared with MECH using the examined harvester (MAN vs. MECH odds ratio: 0.16; 95% confidence interval: 0.10, 0.28). The number of broilers with severe wing injuries did not differ between the loading methods. The number of broilers dead on arrival was greater in mechanically loaded flocks (MAN vs. MECH odds ratio: 0.26; 95% confidence interval: 0.10, 0.68), but lower than in comparable studies. We observed a lower average stocking rate than targeted in the drawers of MECH containers, most likely because the used harvester can adapt to short-term changes in weight and adjust the stocking rate during the loading process. A longer total loading duration in MAN was associated with an increase of wing hematomas, and the involvement of more working people per 10,000 broilers during MAN was associated with a lower occurrence of hematomas. The total loading duration in MECH had no notable influence on the occurrence of injuries. Physical conditions of the involved personnel might play a larger role in MAN than in MECH. The harvester that was examined should be further developed to reduce the occurrence of hematomas. Our results indicate that the choice of loading method alone does not determine the injury risk, and multiple factors are associated with broiler welfare during loading. It is important that the chosen method is performed under the most adequate conditions.

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].…”

A comparison of two manual catching methods of broiler considering injuries and behavior

“…Hematomas on the wing occurred in 1.3% and fractures of the wing in 0.77% of manually caught broilers ( Gocke, 2000 ). Mönch et al (2020) found severe wing injuries in 1.0% of the manually caught broilers examined directly after catching on-farm and hematomas of the wings in 1.5%. Already in an earlier study by De Koning et al (1987) , 11.8% of the broilers showed a hematoma on the wing, however, the broilers were examined at the slaughterhouse after plucking.…”

“…Our study was part of a larger project with 2 further subprojects, published by Wolff et al (2019) and Mönch et al (2020) . Wolff et al (2019) , investigated the stress parameters of broilers comparing the 2LCM and mechanical loading.…”

“… Wolff et al (2019) , investigated the stress parameters of broilers comparing the 2LCM and mechanical loading. Mönch et al (2020) investigated the welfare impacts and circumstances during loading of 2LCM and mechanically loaded broilers. Wolff et al (2019) observed that 68.6% of the broilers showed wing flapping during the 2 LCM.…”

“…In previous studies, it was observed that the majority of injuries resulting from catching and transport were fractures, dislocations and bruises of legs, wings and breast ( de Koning et al, 1987 ; Nicol and Scott, 1990 ; Gocke, 2000 ; Nijdam et al, 2005a ; Langkabel et al, 2015 ; Jacobs et al, 2016 ; Kittelsen et al, 2018 ; Mönch et al, 2020 ). Gocke (2000) dealt with the comparison of 1LCM and mechanical catching and observed the majority of injuries on the wing.…”