Consumer Perception Versus Scientific Evidence About Alternatives for Manual Catching of Broilers in Belgium E. Delezie,*1 W. Verbeke,† J. De Tavernier,‡ and E. Decuypere* *Faculty of Bioscience Engineering, Department of Biosystems, Division Livestock-Nutrition-Quality, University of Leuven, Kasteelpark Arenberg 30, B-3001 Heverlee, Belgium; †Faculty of Bioscience Engineering, Department of Agricultural Economics, Ghent University, Coupure Links 635, B-9000 Ghent, Belgium; and ‡Faculty of Theology, Research Unit of Theological Ethics, Leuven, University of Leuven, Sint-Michielsstraat 6, B-3000 Leuven, Belgium
Key words: catching poultry, bottleneck, consumer, perception, survey 2007 Poultry Science 86:413–419
rates of injuries to the broilers. Lacy and Czarick (1998) as well as Knierim and Gocke (2003) concluded that the mechanization of broiler harvesting resulted in fewer injuries and therefore improved welfare. Although a great deal of attention is devoted to improving welfare of broilers, the health of poultry catchers also needs attention. From a point of view of human wellbeing, the conditions for the catchers are improved during mechanical catching, greatly reducing bending and lifting (Nielsen and Breum, 1995; Metheringham and Hubrecht, 1996). Although some studies concluded that there were no adverse effects of mechanical catching concerning stress level and injuries, i.e., without pointing to specific beneficial effects (Ekstrand, 1998; Nijdam et al., 2005), it can be stated that mechanical catching is a viable alternative to manual catching from an animal welfare and scientific point of view. The success of a catching machine, however, will not be determined only by it being economically favorable and animal and human friendly. It is equally important that this new technology is accepted by the general public (Delezie et al., 2006) because new techniques that do not meet with the approval of consumers may not succeed
INTRODUCTION The intensive industrial conditions under which poultry are kept result in commercial broiler chickens being exposed to a number of potential stressors (Elrom, 2000). The catching and loading of broilers prior to transport is a process causing stress and injuries. A considerable number of technical innovations have been presented, all aiming at facilitating the catching of birds before slaughter. Mechanical catching has been adopted as a realistic alternative to manual catching (Knierim and Gocke, 2003; Delezie et al., 2006). A major advantage of mechanical catching is that broilers are no longer held or carried inverted. Inverted handling increases the duration of tonic immobility (Delezie et al., 2006) and elevates plasma corticosterone (CORT) concentrations (Kannan and Mench, 1996), indicating that birds are more stressed. The manual catching conditions also result in considerable
2007 Poultry Science Association Inc. Received August 18, 2006. Accepted October 16, 2006. 1 Corresponding author:
[email protected]
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objective scientific facts. This research was focused on questions and issues related to the consumers’ expected bottlenecks and motives for accepting these technologies after being exposed to video segments of each catching method. In general, the gap between consumer perception and scientific evidence related to manual and mechanical catching is limited. For those bottlenecks where science is inconclusive, respondents also have no explicit preference. Despite absence of major gaps between consumer perception and expert knowledge, preferences of particular consumer segments do not align well with scientific evidence. This holds in particular for female, younger, urban individuals who attach high importance to animal welfare issues.
ABSTRACT Commercial broiler chickens are exposed to a number of potential stressors prior to slaughter, including catching, crating, and transportation. To ameliorate animal welfare and prevent product quality loss during these processes, numerous scientific studies have been performed. As a result, different technical innovations have been presented such as mechanical catching instead of manual catching. The success of a catching machine as an alternative for manual catching of broilers will not only depend on its economic, animal, and human welfare benefits but also on its acceptance by society and consumers. The aim of this research was to assess if individuals’ subjective perceptions of catching methods align with
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Structure of the Questionnaire
Gender
Video segments of manual and mechanical catching were shown to the respondents. Two video segments of catching machines were shown: the Chicken Cat Harvester and the Super Apollo, which mainly differ in the way broilers are gathered. The catching machine Chicken Cat Harvester has a collecting unit in the front containing 3 rotating, hydraulically driven cylinders. The surface of the cylinders is covered with long flexible rubber fingers, which forces the broilers onto the conveyor belt. The catching machine Super Apollo has a frontal, completely automated gathering system. A 6-m-wide loading platform catches the birds, and another conveyer belt covered with rubber fingers takes the birds to a loading unit at the rear of the machine. The video segments were shown in random order to avoid bias from segment sequence. Information provision was limited to showing video segments. No further verbal or written information about the catching methods was provided. A questionnaire consisting of 4 sections was designed to gain information about respondents’ preferences and their perceived bottlenecks (i.e., perceived barriers) for accepting the different catching methods of broilers after exposure to video segments. In the first section, respondents were probed about their involvement with agriculture. Next, awareness of both catching methods was measured on a nominal scale. Participants were also asked if they are interested in knowing more about the catching of broilers. In the second section, respondents were asked to indicate on a nominal scale which poultry catching method they preferred after exposure to the video segments. In the third section, perceived bottlenecks were assessed for manual and mechanical catching based on literature review. First, consumers had to indicate on a nominal scale for each of 5 possible bottlenecks during which catching method the bottleneck was less severe. Second, 7 and 8 possible obstacles were presented for manual and mechanical catching, respectively. Consumer perception of operations being (dis)advantageous from the viewpoint of animal or human welfare was measured on a 5point interval scale ranging from not at all detrimental to neutral to very detrimental for bird welfare. Based on the evidence that the way broilers are picked up from the ground has an major impact on animal welfare, the practices of holding the birds upside down, holding a lot of birds in each hand, and the way birds fall into the containers were included as potential detrimental actions for welfare during manual catching. The statements “the way broilers are dished up by the machine,” “working with conveyor belts”, and “the way birds fall into the containers” were included for mechanical catching. Also, the rate of catching, the stocking density in the cages, and the noise in the poultry house were included because they are relevant for animal welfare. Finally, consumer perception of the working conditions of the people was measured. Fourth, consumers were asked to rank improvement of animal welfare, improvement of human
Age
Living environment
Education Involvement with agriculture Involvement with the poultry sector
Male Female <20 yr 20 to 30 yr 30 to 40 yr 40 to 50 yr >50 yr City District quarter outside the city Center of rural district Countryside Lower secondary Higher secondary University Yes No
55.0 45.0 21.6 43.0 13.4 10.5 11.5 15.4 22.4 17.5 44.7 52.8 19.3 27.8 45.4 54.6
Yes No
17.3 82.7
commercially. Animal welfare is an issue of increasing significance for consumers (Verbeke and Viaene, 2000; Bornett et al., 2003). The aim of this research is to assess consumer preferences for alternative harvesting methods and to investigate if individuals’ subjective perceptions align with objective scientific facts. This research moves forward from simple assessments of consumer concerns about the technology. Through identifying benefits and drawbacks as perceived by consumers and through comparing these perceptions with most plausible scientific evidence, recommendations for wider scale introduction and communication about the catching technologies can be formulated.
MATERIALS AND METHODS Research Methodology Quantitative data were gathered through a questionnaire-based survey with consumers in Belgium during the period December 2004 to April 2005. The total sample consisted of 450 subjects. Nonprobability convenience sampling was used for respondent selection (Malhotra, 2004). Sample characteristics are presented in Table 1. The sample consisted of 55% men and 45% women, ranging from 18 to 70 yr (mean = 30 yr). The sample includes respondents from different places of living (urban vs. rural) and education levels. Distributions of gender, age, education, living environment, and frequency of eating poultry show that the sample covers a wider range of socio-demographic profiles, although the sample is not statistically representative for the population. This holds especially for younger individuals and people involved with agriculture and the poultry sector. In this sample, 17% of the respondents are involved with the poultry sector, which is a substantial overrepresentation as compared with the Belgian population. However, overrepresentation of people involved with agriculture was needed to compare opinions of individuals with and without awareness of the poultry catching practice.
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Table 1. Socio-demographic characteristics of the valid sample (% of respondents, n = 450)
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CONSUMER PERCEPTION VERSUS SCIENTIFIC EVIDENCE Table 2. Profile of consumers with high importance attached to animal welfare and preference for manual or mechanical catching
Item
High importance attached to animal welfare
Manual
Mechanical
Gender Age Living environment Involvement with agriculture Education level Interest in agriculture
Women >30 yr Urban areas No Lower Lower
Women Young people (<20 yr) Urban area No Lower Lower
Men 20 to 40 yr Rural Yes Higher Higher
Data Analysis Procedure The questionnaire was pretested, modified, and refined before starting the fieldwork. The data were analyzed by means of SPSS 12.00 (SPSS, 2003). The analyses include construct reliability analysis using Cronbach’s alpha, cross-tabulation with χ2 statistics, and independent samples t-tests and ANOVA for comparison of mean scores. Null hypotheses were rejected at the 5% or lower level of significance.
RESULTS AND DISCUSSION Individual Characteristics Most of the respondents had no previous awareness of catching methods (42.5%), or were only acquainted with manual catching (40%), whereas the percentage of people aware of mechanical catching only (1%) or both catching methods (16.5%) was low. No more than 12% claimed to intend to buy less poultry if mechanical catching would be applied. About 15% scored neutral on this statement, and 73% claimed that they would not change their buying behavior. Significantly more women attached high personal relevance to animal welfare (χ2 = 39.252; P = 0.0001). Furthermore, consumers aged above 30 yr (χ2 = 18.676; P = 0.001), being vegetarian (χ2 = 23.215; P = 0.0001), having no involvement with the poultry sector (χ2 = 66.877; P = 0.0001), and living in urban areas (χ2 = 34.254; P = 0.0001) reported higher personal importance attached to animal welfare. Those consumers also had a lower knowledge (F = 22.702; P < 0.0001) and higher interest in knowing more about catching methods (r = 0.397; P < 0.0001), a higher intention to buy less poultry meat if mechanical catching would be applied (F = 43.447; P = 0.0001), and a lower consumption frequency of poultry meat (F = 38.391; P = 0.0001; Table 2). These findings suggest that differences in involvement with agriculture are reflected in the importance consum-
ers attached to animal welfare. As mentioned by Brom (2000), the distance between consumers and farmers has widened, and direct contact with food production has faded away. This results in a decreasing knowledge of production processes and lower confidence in the production system (Korthals, 2001; Verbeke, 2005). Sharp and Tucker (2005) also showed that greater social distance from agriculture is related to greater concern about livestock production, animal welfare, and product quality.
General Preference for Catching Method Women and younger people (<20 yr) scored higher in their preference for manual catching (P < 0.0001), whereas the middle age group (20 to 40 yr) chose mechanical catching, and the oldest respondents (>40 yr) had in the main no specific preference (P = 0.003). There was a tendency for stronger preference for manual catching among urban residents (P = 0.089). Respondents without involvement with agriculture (P = 0.0001) and the poultry sector preferred manual catching (P < 0.05). Vegetarians had mainly no preference for a catching method, most likely because they did not want broilers to be caught (P = 0.052). Respondents who attach high importance to animal welfare (P < 0.0001) and who have low interest in agriculture (P = 0.001) had a higher preference for manual catching (Table 2). Several studies showed that mechanization of the catching process improves the welfare of broilers when using a well-designed machine (Duncan et al., 1986; Elrom, 2000; Knierim and Gocke, 2003; Delezie et al., 2006). Our results indicate that consumer preference for catching methods are not fully in line with current scientific evidence. The most critical group toward mechanical catching are people who are young, urban residents, women, and respondents attaching high importance to animal welfare. Nevertheless, a substantial part of the respondents regarded public acceptance of mechanical catching as unproblematic. The socio-demographic characteristics of consumers choosing mechanical catching vs. those having no preference did not differ significantly.
Perceived Bottlenecks for Accepting Manual and Mechanical Catching Further analyses focused on different potential bottlenecks of the catching methods. Table 3 shows that respon-
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welfare, and the economics of the catching method in order of perceived importance when making a judgment about the acceptability of a particular catching method. Finally, the questionnaire included socio-demographic characteristics such as age, gender, education, and living environment (Table 1).
Preference of catching method
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DELEZIE ET AL Table 3. Consumer preference for catching method on 5 possible bottlenecks during the catching of broilers, frequency distribution (%, n = 450) Preference of catching method Action The The The The The
way broilers are picked up from the ground way birds fall into the containers rate of catching noise in the poultry house working conditions of the catching team
Mechanical
No preference
Total
29.5 38.9 30.4 30.2 6.3
48.5 23.1 45.2 25.2 65.3
22.0 38.0 24.4 44.6 28.4
100 100 100 100 100
within the range accepted for active but nonfrightened fowl (Duncan et al., 1986). A majority (65.3%) of respondents prefer mechanical catching with regard to the working conditions of the catching team. Indeed, manual bird catching is not only deleterious for broilers but also not the most pleasant aspect of broiler production for people (Kettlewell and Mitchell, 1994; Metheringham and Hubrecht, 1996). From a human health perspective, the circumstances for the catchers during mechanical catching are improved; bending and lifting is reduced to a certain level (Lacy and Czarick, 1998). The extent to which consumers themselves experience some practices during catching as bottlenecks for the welfare of animals and humans is presented in Table 4. Respondents had a negative perception toward the way broilers fall into the containers during manual (x = 3.67) as well as during mechanical catching (x = 3.73). The variable stocking density (x = 3.64) is another important bottleneck for manual catching. Density of crated broilers has a major role in the ability of the bird to cope with environmental changes as a homeothermic animal and to prevent lateral movement, which may result in physical injury (Elrom, 2000). During manual catching, catchers are responsible for a homogeneous density of broilers in each drawer of the container. This is done by counting the birds. When several catchers fill the same container, it occurs that too many or too few broilers are put in the crates of the containers. People believe that this practice can be detrimental for the broilers; 63.5% scored this bottleneck as detrimental. Density variations between cages are no longer an issue during mechanical catching because the catching machines are equipped with a weighing device for density control during loading. Another benefit of using machines for catching is that, unlike manual handling, which has the reputation of becoming rougher as the process continues, mechanized handling is consistent from start to finish. In general, this advantage of mechanical catching is acknowledged by the respondents. This is reflected in the high percentage (about 72%) of the respondents scoring this bottleneck as neutral or even not detrimental at all (x = 2.78). Relatively low to neutral scored perceptions were that holding the broilers upside down ( = 2.89) and the rate of catching (x = 2.85) are harmful for manually caught broilers. At first sight, contradictory results are obtained for both above-mentioned bottlenecks. Both bottlenecks are scored as more detrimental during mechanical catch-
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dents prefer mechanical catching for the way broilers are picked up from the ground (48.5%), for the rate of catching (45.2%), and for the working conditions of the catching team (65.3%). In contrast, only 23.1% found mechanical catching the best option for the way broilers fall into the containers. With respect to noise level in the poultry house, about half of the respondents had no preference for a specific catching machine. These findings corroborate scientific evidence. The greatest benefit of the catching machine is the reduced number of leg injuries, because birds are no longer grasped and carried by the legs (Gregory and Austin, 1992; Knierim and Gocke, 2003). Upright handling is also less stressful to broilers as compared with inverted handling (Kannan and Mench, 1996), and mechanical catching reduces the time birds are in physical contact with humans, which reduces the intensity of physiological stress responses (Duncan et al., 1986). Most respondents believe that the rate of mechanical catching is more appropriate for the welfare of the broilers. A catching team can load between 1,000 to 1,500 broilers per person per hour, but because catching usually takes 5 h, it is difficult to maintain the same working pace (Kettlewell and Mitchell, 1994). It is important to note that machines catch at the same pace as manual catching crews (Lacy and Czarick, 1998) but do not get tired or slow down or become rougher toward the end of the shift. Respondents do not have an explicit choice of catching method concerning the way broilers fall into the containers, which is also inconclusive from a scientific point of view. Risk of stress and injuries because of birds’ wingflapping response depends on the height from which the birds are dropped (Duncan et al., 1986). Elrom (2000) found plasma CORT levels and wing flapping increased with the height of the drop. This damage can be reduced if the manual catching team handles the broilers properly and throws the broilers from nearby in the containers. Therefore, gentle application by the catching team can result in high improvement of animal welfare (Nijdam et al., 2005). During mechanical catching, the conveyor belt at the end of the machine is adjustable in height. Still, this aspect of mechanical catching is potentially problematic and provides scope for further improvement. At first sight mechanical catching looks more detrimental to broilers because of noise levels of the machine. Therefore, it is not surprising that only 25.2% of the consumers preferred mechanical catching when taking into account the noise. The noise of the machine can lead to increased CORT concentrations; however, the level is
Manual
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CONSUMER PERCEPTION VERSUS SCIENTIFIC EVIDENCE Table 4. Consumer perceptions about the bottlenecks for manual catching (%, n = 450), mean score, and SD on 5-point scale1 Item
Neutral
Detrimental
Mean
SD
36.5 16.0 35.8 26.9 32.0 15.3 30.7
26.5 18.0 36.0 35.0 34.4 21.2 29.6
37.0 65.8 28.0 38.1 33.5 63.5 39.7
2.89* 3.67 2.85* 3.04* 2.91 3.64 3.03
1.18 1.09 1.16 1.16 1.11 1.09 1.17
25.6 13.9 30.2 54.7 37.0 37.5 36.1
24.0 18.8 30.2 35.6 34.3 34.8 36.5
50.4 67.3 39.7 9.7 28.7 27.6 27.4
3.29 3.73 3.08 2.28 2.81 2.78 2.85
1.21 1.07 1.20 1.03 1.11 1.16 1.18
During manual catching The way broilers are picked up (upside down) The way broilers fall into the container The rate of catching The working conditions of the catching team The noise in the poultry house The stocking density in the cages Holding a lot of birds in each hand During mechanical catching The way broilers are picked up (machine) The way broilers fall into the containers The rate of catching The working conditions of the catching team The noise in the poultry house The use of a machine Working with conveyor belts
1 The categories “very detrimental” and “detrimental” and “not detrimental” and “not at all detrimental” from the initial 5-point scale have been merged to simplify. *Indicates significant difference at P < 0.05 between the same events during manual and mechanical catching (independent t-test, ratings were made on 5-point scales).
ing compared with manual catching, whereas the mechanical way of picking up birds from the ground and the rate of catching were preferred above the manual catching method. A number of individual differences in perception of bottlenecks are discovered. Women, people with a higher education level, low involvement with agriculture, low awareness of catching methods, living in urban areas, low interest in agriculture, and high importance attached to animal welfare perceived all bottlenecks as significantly more detrimental for animal welfare (all P < 0.05). A multivariate ANOVA was applied to determine respondents’ views regarding the possible bottlenecks for each catching method according to their preference for a particular catching method (Figure 1). Only those bottlenecks being significantly different between manual and mechanical catching are included. Overall, no difference was observed in terms of respondents’ ranking of the bottlenecks: falling into the containers received the highest scores, whereas the working conditions of the catchers received the lowest. Significant interactions between catching method, preference, and
bottlenecks were observed. The interactions can be interpreted by inspection of Figure 1a and 1b. People with a preference for manual and mechanical catching rated the bottlenecks with respect to animal welfare lower and higher during manual catching, respectively. The opposite was observed for the bottlenecks during mechanical catching. Respondents without preference for one of the catching methods rated the bottlenecks in between the scores of the respondents with a manual or mechanical preference. A difference among scores by the 3 groups was observed for the picking up of broilers during mechanical catching. The contradictory findings, i.e., about the catching method preferred for the picking up of broilers (as mentioned above), are caused by respondents preferring manual catching and therefore scoring the bottlenecks during mechanical catching as very detrimental. Consumers preferring mechanical catching also express greater concern about the bottlenecks during manual catching; however, a higher dispersal between scores of the different groups was observed for these bottlenecks during mechanical catching.
Table 5. The importance of subsequent aspects in the preference for mechanical catching (mean score and SD) Preference of catching method1 Item Broilers can be caught mechanically even if this would only yield an economical advantage. Broilers can be caught mechanically even if this would only yield an improvement of human welfare.
1
2
3
2.27b (1.22)
3.16a (1.31)
2.83b (1.50)
2.41b (1.31)
3.29a (1.28)
2.86b (1.44)
a,b Scores in 1 row with a different superscript are significantly different (1-way ANOVA and post hoc Tukey multiple comparison test). 1 1 = manual; 2 = mechanical, 3 = no preference. The higher the mean value, the more the respondents agreed with each statement. Mean (SD) for statements relating to perceptions about importance of different aspects related to the catching process.
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Not detrimental
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ACKNOWLEDGMENTS
Figure 1. A) Mechanical catching: Scores of bottlenecks of the different groups of respondents during mechanical catching (mean values). 1 = not at all detrimental; 5 = very detrimental. B) Manual catching: Scores of bottlenecks of the different groups of respondents during manual catching (mean values). Group 1 = manual; group 2 = mechanical; group 3 = no preference. a–cScores with a different letters are significantly different (1-way ANOVA and posthoc Tukey multiple comparison test).
Perceived Importance of Economics and Animal and Human Welfare Half of the respondents (53%) ranked animal welfare as the most important criterion taken into account for accepting an alternative for manual catching. Human welfare and economics were ranked on the second and third place, respectively. Significant differences depending on the preferred catching method were observed. Fewer respondents preferring manual catching would accept mechanical catching if only human welfare (x = 2.41) or only the economics (x = 2.27) were improved, as compared with the respondents preferring mechanical catching (Table 5).
The authors would like to thank Stefan Aerts and Filiep Vanhonacker for their skilled assistance in data processing. This research was funded by a PhD grant from the Institute for the Promotion of Innovation through Science and Technology in Flanders (IWT-Vlaanderen).
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Respondents indicated that cost increases from mechanical catching should be accounted for mainly by consumers (52%), by government (36%), or to a lesser extent by farmers (12%). Finally, respondents were asked if they would change their preference for manual catching if studies would undoubtedly report that mechanical catching is a better method for catching broilers. High scores (3.77 ± 1.22 on a 5-point scale) indicate that scientific knowledge may cause a lot of people to alter their preference. Especially those respondents without prior awareness of the catching of broilers or those attaching a lot of importance to animal welfare are prone to shifting their preference when convinced by scientific evidence. As indicated in this study, results of scientific studies are likely to be important for consumers and for consumer acceptance of a husbandry technique. It can be concluded that gaps between consumer perception and scientific evidence related to bottlenecks of manual and mechanical catching are limited. Respondents’ beliefs in the benefits of a catching machine are rather high. For those bottlenecks where science is inconclusive, respondents also have no explicit preference. Despite absence of major gaps between consumer perception and expert knowledge of bottlenecks for poultry catching methods, preferences of some specific consumer segments do not align well with scientific evidence. This holds in particular for female, younger, urban residents who attach high importance to animal welfare. Targeted communication efforts to these consumer segments are recommended.
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