Open Veterinary Journal, (2026), Vol. 16(4): 2392-2407

Case Report

10.5455/OVJ.2026.v16.i4.41

Chick welfare in a large, commercial chicken hatchery: A case study

Jenny L. Mace^1,2* and Andrew Knight^3,4,5

¹Centre for Ethics, Philosophy, and Public Affairs, University of St Andrews, St Andrews, UK

²Mace Animal Welfare, Dunfermline, UK

³School of Veterinary Medicine, College of Environmental and Life Sciences, Murdoch University, Murdoch, Australia

⁴School of Environment and Science, Griffith University, Nathan, Australia

⁵Animal Welfare Research Group, Faculty of Health and Wellbeing, University of Winchester, Winchester, UK

*Corresponding Author: Jenny L. Mace. Centre for Ethics, Philosophy, and Public Affairs, University of St Andrews, St Andrews, UK and Mace Animal Welfare, Dunfermline, UK. Email: jm609 [at] st-andrews.ac.uk

Submitted: 17/11/2025 Revised: 22/02/2026 Accepted: 03/03/2026 Published: 30/04/2026

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Abstract

Background: Worldwide, approximately 1.8 billion chicks are hatched every month in commercial hatcheries. A typical commercial hatchery is a high-speed and stressful environment. Not only is chick welfare impacted while at the hatchery, but chickens’ early life experiences can also have long-lasting impacts on their welfare after they are moved from the hatcheries. Additionally, the capacity to suffer in chick embryos (i.e., to experience pain, distress, or other prolonged negative welfare) may commence approximately three days before hatching by embryonic day 18—and likely earlier. Based on this knowledge, this case study sought to assess the prevalence of welfare problems in an exemplar US hatchery.

Case Description: A 4-minute video of undercover footage from a large commercial US hatchery was reviewed. Animal-based indicators detailed by the European Food Safety Authority were used to identify animal welfare problems present in the footage.

Conclusion: Overall, 17 severe welfare problems with concurrent suffering were identified in the undercover footage. The most severe harms were associated with a high risk of injury or death. These most commonly arose from unsafe equipment that caused chicks to get stuck in machinery, fall off conveyor belts, or be unintentionally put through a high-temperature washer. Late-stage chick embryos were also frequently crushed. The lack of prompt euthanasia meant that many chicks and embryos experienced inhumane deaths. This evidence suggests that there are significant levels of harm and concomitant suffering experienced by many chicks and chick embryos at the aforementioned hatchery—and likely many other commercial hatcheries globally.

Keywords: Chick welfare, Hatchery, Chicken welfare, Poultry welfare.

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Introduction

Globally, the poultry industry—along with smaller sectors such as backyard chicken keeping and scientific research—produces an estimated 1.8 billion chicks each month (McNeill, 2018). The United States alone accounts for approximately 900 million of these hatchings monthly (USDA, 2024). Modern hatcheries employ a high degree of automation, carrying chicks through various processing phases such as hatching, conveying, sexing (for layer breeds), maceration of unwanted males from layer lines, vaccination, and beak trimming (Knowles et al., 2004). Mechanical systems in hatcheries can expose chicks to shock acceleration forces of nearly 920 m/s² (Knowles et al., 2004) and drops of up to 55 cm (Haas, 2020), with noise levels reaching about 70 dB (e.g., the sound of a vacuum cleaner) alongside combined manual and mechanical handling (EFSA, 2023). The largest and most technologically advanced facilities can handle as many as 100,000 chicks each hour—or roughly 4 million weekly (Ceva Ecat-iD Campus, 2024)—while throughputs of 1 to 2 million chicks per week are common (Knowles et al., 2004; Graber, 2019).

Concerns have been raised about the welfare of chicks—and possibly chick embryos—within hatchery systems, highlighted in work by Knowles et al. (2004; p. 417), the RSPCA (2026), and in undercover evidence published by the animal advocacy organization Animal Equality USA (2024a). Identified welfare risks include painful or fatal injuries caused by damaged or unsuitable equipment, poor maintenance, and inadequate staff training or monitoring. Our recent systematic review (Mace and Knight, 2025) indicated that the capacity for pain and distress likely develops from embryonic day (E) 13. Based on this, the present study evaluated the welfare implications for chicks and embryos processed in a typical commercial hatchery by reviewing undercover footage recorded by Animal Equality USA in 2021 (Animal Equality, 2024a). We sought to identify potential suffering, distress, or other animal welfare problems.

This study adopted established scientific definitions of pain, suffering, distress, and animal welfare. Pain is defined as “an unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage” (Raja et al., 2020). “Suffering is one or more bad feelings continuing for more than a short period” (Broom, 2014). To define distress, stress must first be understood as “the biological response elicited when an individual perceives a threat to its homeostasis” (Moberg and Mench, 2000). Distress, therefore, occurs “when the stress response threatens an individual’s wellbeing” (Moberg and Mench, 2000). According to Broom (2014; p. xiv), an animal’s welfare represents the degree to which he or she is coping successfully with his or her environment.

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Case Details

This study comprised an animal welfare assessment of publicly available video footage of Foster Farms hatchery in California in 2021, collected during an undercover investigation by Animal Equality USA (Animal Equality, 2024a). This study sought to answer the research question: Based on recent scientific evidence indicating the earliest timepoint at which chicks have the capacity to suffer, what welfare problems, distress, and suffering can be identified in the Foster Farms hatchery footage? To achieve this, for full contextualization, a 42-minute and 42-second video supplied by Animal Equality USA was first studied (Animal Equality, 2024b). However, this extensive footage was not publicly available by November 2025, and so to allow independent verification, an abridged 4-minute publicly available video (Animal Equality, 2024a) was instead used for this analysis. All instances of the animal welfare problems identified in the lengthier footage also featured in the abridged version—except three, which are made explicit in the Discussion section.

The footage stemmed from one body camera of an undercover investigator (working as a staff member). There were no problems with the quality of the video footage. There was no audio in the video footage; thus, only visual content was analyzed. Footage was watched twice—and slowly, pausing each time welfare problems, notes, and timestamps were recorded, and for closer inspection of still images. To optimize understanding, the investigator’s field notes were also read in addition to the official complaint lodged by Animal Equality to the Stanislaus County District Attorney (Hanneken, 2021). For instance, numbers of chicks processed does not seem readily available for the Foster Farms hatchery. However, a staff member at Foster Farms reportedly told the undercover investigator that the hatchery processed up to 3 million chicks per week in 2021, with plans to scale up to 5 million in 2022 (Hanneken, 2021). Figure 1 outlines the common stages in a typical “broiler” chick hatchery.

Fig. 1. Exemplar stages in a 'broiler' chick hatchery. Note: This is based on the undercover investigator’s report in Exhibit B of the Complaint (Hanneken, 2021) and Knowles et al. (2004). A similar version appears in Mace and Knight (2025).

The European Food Safety Authority’s (EFSA’s) scientific opinion regarding the “Welfare of broilers on farm” (EFSA, 2023) was the main reference text used for analyzing the welfare problems identified, due to its inclusion of welfare at the hatchery and its thorough discussion of measures for identification of welfare harms and hazards. A table was created to summarize the welfare problems identified in the footage, along with their precise timestamps within the video footage. Screenshots indicating the welfare concerns were also taken and are provided in the Supplementary Material.

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Discussion

Animal welfare problems (pain, distress, suffering) identified in the undercover footage

Table 1 summarizes the 17 most serious animal welfare problems evident in the video footage (for less serious concerns, see section: Less severe welfare problems). They were mostly acute welfare insults spanning blunt force trauma, a variety of injuries (e.g., being caught in machinery or live scalding), slow/distressful/painful deaths, and hypothermia. Also present were several extremely high-risk welfare hazards, such as falling from conveyor belts and risks of crushing, drowning, or becoming soaked (risking secondary hypothermia). Three problems identified are of unknown cause; however, it is likely they all relate to equipment. If so, this would mean all of the welfare problems and hazards identified are related directly or indirectly to machinery/equipment.

Table 1. Summary of the most severe welfare problems identified in the 4:17-minute foster farms video footage (Animal Equality, 2024a).

These aforementioned serious welfare problems and hazards are foreseeable within modern hatcheries and have mostly been well documented as risks within scientific studies. For instance, Knowles et al. (2004; p. 417) found chicks fell from conveyor belts to the floor to varying degrees at different UK hatcheries, frequently resulting in severe animal welfare risks—including injury, death, or increased handling stress. They also highlighted the need for continuous monitoring of all equipment used to safeguard chick welfare. Similarly, the RSPCA has recognized the need for attachment of sufficiently lengthy sides to conveyor belts and careful equipment design, to ensure chicks cannot get stuck in equipment (RSPCA, 2026). The EFSA (2023; p. 3) has also highlighted the high vulnerability of young chicks to cold. This is due to chicks being poikilothermic—meaning that they are not yet able to effectively regulate their own body temperature, creating high vulnerability to adverse external conditions (International Poultry Welfare Alliance or IPWA, 2022), which can quickly lead to death. The severity of this problem is recognized by the IPWA (2022; p. 60), which refers to very wet chicks as being “injured,” alongside injuries resulting from equipment malfunctions.

It should be noted that the frequency of the welfare problems and hazards in Table 1 is not necessarily representative of, nor proportionate to, those occurring in a typical 4-minute period at the hatchery; there could be more or less frequent incidences of such causes of suffering depending on factors such as production speeds, equipment maintenance, staffing levels, skills and experience, and random variation. Nevertheless, the video footage makes it clear that the welfare problems identified are not isolated instances, and the related scientific studies make it clear that most of these problems are well recognized within commercial hatcheries and are preventable. In many countries or regions, including California, where Foster Farms hatchery is based, permitting avoidable harm to farmed animals constitutes illegality (Shouse Law, 2025).

In the following, identified indicators of poor welfare will first be discussed, followed by mode of death—as this was one of the most serious animal welfare problems identified. Lastly, some of the slightly less severe welfare problems identified will be discussed.

Indicators of compromised animal welfare

In the footage, the chicks and chick embryos are displaying common avian indicators of poor animal welfare. The EFSA (2023; p. 95) differentiates between general (“iceberg”) and specific indicators of poor welfare. Iceberg indicators illustrate the general welfare of an animal, which is often affected by multiple circumstances; in contrast, specific indicators often indicate precise causes of a particular welfare problem. High mortality (p. 97) is an example in the footage of an iceberg indicator, reflecting poor welfare that could be caused by various welfare problems, sometimes in combination—such as cold stress, mechanical/manual handling stress, prolonged thirst or hunger, or overstimulation. In contrast, the number of chicks falling to the floor from a conveyor belt is an example of a specific indicator of mechanical handling stress (p. 103). Other iceberg indicators evident in the footage include lethargy (p. 97), which can be indicative of cold stress or prolonged thirst (dehydration); and a fear response (p. 99), which can be indicative of mechanical/manual handling stress or overstimulation. Another of EFSA’s specific indicators evident within the footage is a lack of normal resting behavior. This is indicative of overstimulation, or of problems that inhibit normal resting (pp. 3, 102). Two other specific indicators of handling stress—namely, the time required for chicks to stand upright again after being on their back, and the number of orientation/posture changes they partake in when on the conveyor belt (EFSA, 2023)—cannot be accurately measured in the footage due to the high conveyor belt speeds.

The EFSA (2023; p. 72) acknowledges injury/trauma as a “welfare hazard” resulting from inadequately designed machinery; similarly, the IPWA recognizes machine-originating injuries as a “key welfare indicator” for chicks/embryos in hatcheries, and urges remedial action to prevent injuries from occurring (IPWA, 2022). The EFSA (2023; pp. 72, 102) includes “escape attempts” and “resistance to handling” among their animal-based welfare assessment measures for chickens. Both of these measures are evident in the Foster Farms footage; for instance, in clip 00:50, a live chick trapped in machinery is clearly displaying “Attempts to move, run or fly away from a fear-provoking stimulus” (i.e., an escape attempt), and “Moving, running or flying away or attempts to do so (i.e., struggling) at the time of handling” (i.e., exhibiting resistance to mechanical handling). Escape attempts and resistance to handling are indicative of fear responses. Without these measures, it is difficult to measure the fear response objectively in the footage, as the other measure normally used is the Novel Object Test (EFSA, 2023), which is of course not possible to apply to this case.

As mentioned in the previous “Case details” section, the full 42-minute length footage evidenced three extra welfare indicators/problems. These also feature in Table 1. For instance, live chicks were visible on the floor or in crates that were often very still. This can reflect lethargy (EFSA, 2023), whereby chicks sit or stand in one spot motionless and unresponsive to stimuli (EFSA, 2023). Immobility could also indicate fear, as fear decreases the inclination to explore (Meuser et al., 2021). It may also indicate dehydration, hunger, illness, or injury. Such a lack of movement was also evident in stray chicks found in compartments within the machinery that they became stuck in (e.g., at 2:44). In one such instance, one chick exhibited the highly motivated and comforting behavior of preening (lengthier footage only). However, rather than being indicative of good collective welfare, the fact that none of the other chicks in this compartment were displaying this behavior indicates poor welfare for the majority, especially as chicks are flock animals that tend to exhibit the same type of behavior as their flock mates. Preening is such a highly motivated behavior, including for 1-day-old chicks (Sandilands, 2001), that conditions and welfare need to be very poor for an individual chick to refrain from this behavior. It was noteworthy that preening behavior, as a comfort behavior, was completely absent from the 4-minute abridged footage.

Mode of death

The manner in which many chicks were dying deserves particular attention, not least because all the other serious welfare problems and risks identified have a high risk of resulting in eventual death. The methods of death identifiable in the footage included the following:

• Suffocation—discard material (e.g., “subpar” or injured chicks/embryos, egg fluid, shells) was piled atop other “subpar” or injured chicks/embryos in waste bins.
• Drowning—some chicks who fell off the conveyor landed in water from the washer emptying or were covered in egg fluid when discarded.
• Scalding washer water—live chicks were put through the washer, and would also be exposed to any chemicals used, such as disinfectants or detergents.
• Blunt force trauma—such as from crate crashes or trampling via a trolley running over a stray chick on the floor (the latter was evident in the full-length footage).

It is standard practice in the poultry industry to use the term “euthanasia” in regard to any killing at the hatchery or on farm; indeed, even the American Veterinary Medical Association (AVMA) uses the term in their guidelines for an array of different reasons for killing many different animals in a variety of situations (AVMA, 2020). Thus, for consistency, the term is also used in this report. However, there are many instances when the use of this term is not truly accurate. Euthanasia is more correctly defined as killing that is not only humanely conducted, but that is also in the best interests of the animal. This is not normally applicable in cases of recoverable injury (Croney and Reynnells, 2008). The National Chicken Council (NCC, 2022) attests that only AVMA-approved methods of euthanasia are permitted. For chick embryos from E17 up to chicks 72 hours of age, the only euthanasia methods recommended by the AVMA are either inhalation of gases (e.g., carbon dioxide, nitrogen, or argon) or maceration using specially designed equipment (AVMA, 2020). Of note is the exclusion of all of the modes of death listed above in the footage. This clearly results in avoidable pain, distress, and suffering, simply due to a lack of such mandated more humane killing methods being implemented to prevent and minimize these risks.

It is important to note that, while the AVMA does list maceration as an acceptable method of euthanasia, it is contingent upon the equipment being specially designed, high-functioning, and subject to regular checks (AVMA, 2020). It seems from the field notes (Hanneken, 2021; AE000386) that this is the intended method of euthanasia at Foster Farms hatchery. However, in reality, this was not in reliable operation as a swift means of euthanasia when required. This was due to 1) a lack of a designated checker of stray/injured chicks (other than of chicks directly on the conveyor belts), 2) the macerator not always being switched on (AE0003; Hanneken, 2021), and 3) staff not prioritizing this course of action—neither for individual cases, nor for mass casualty cases.

Less severe welfare problems

The welfare insults discussed in the previous sections are so severe that it can be difficult for less severe concerns to attract attention. Nevertheless, it remains important to note that the general high-stress environment evident within the footage—including deprivation of feed/water, highly crowded conditions, high-velocity conveyor belts (with rollers, drops, and gradients), and handling (human and mechanical)—creates significant welfare concerns in and of itself. For instance, the EFSA (2022; p. 6) reports that there is a 66%–100% certainty of mechanical handling stress arising from conveyor speeds above 27 m/minute, drops of over 28 cm, and changes in velocity of more than 0.4 m/s. High cumulative stress levels not only contribute to negative affective states (i.e., lengthier negative affective states such as anxiety or depression, which result from the accumulation of adverse experiences) but can also impair coping mechanisms. For instance, this can include the immune system becoming compromised, leading to reduced chances of successfully coping with other welfare insults—generating a positive feedback loop (Moberg and Mench, 2000; Hedlund, 2022). Correlations have also been found between chicks experiencing high stress and more fearful behaviors when they become adult chickens, with higher fear levels relating to higher levels of injurious feather pecking—a common, serious welfare concern in adult chickens (Nicol, 2015). Thus, low welfare at the start of chicks’ lives can affect them in adult life too; indeed, hatchery conditions have even been suggested to foster long-term pessimistic moods in chickens (Hedlund, 2022).

The EFSA (2023; p. 104) summarizes some of these less severe welfare problems as overstimulation (a form of stress), particularly in regard to novel stimuli that are likely to elicit fear. This is especially pertinent for chicks as they are an avian species that undergoes imprinting (Nicol, 2015). Imprinting is the phenomenon of attaching to an individual (the mother hen, most naturally) immediately after hatching, with the affiliation beginning during incubation through an exchange of vocal calls. The exceedingly fast-paced and noisy environment of a modern hatchery, with exposure to hundreds of changing individuals, is unlikely to lead to successful or beneficial imprinting. In contrast, it may simply create more distress if this crucial behavioral and learning process is not properly established.

Implications

This case study identified 17 severe welfare problems existing for both chicks and chick embryos in one conventional large commercial US hatchery. These welfare problems are already known to be significant welfare hazards within commercial hatcheries. As such, the NCC states machinery should be specially designed with high sides to prevent chicks straying, and the IPWA calls for injuries and culls to be monitored, along with the implementation of plans to mitigate culling and injury risks.

The findings from this study should serve as a reminder of and emphasize the importance of such long-standing advice from leading industry organizations. Every commercial hatchery should urgently establish the prevalence of animal welfare problems on their sites and implement action plans to remedy the problems identified. Legislation should be enacted to aid in the delivery of this, as voluntary implementation appears ineffective. Such action on chick welfare in hatcheries could be expected to significantly improve animal welfare levels for billions of chicks globally each year. It could also help to improve the welfare problems experienced by some adult chickens through improved conditions in early life.

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Conclusion

Based on recent knowledge advancements concerning the capacity for suffering almost certainly being present by day 18 and possibly as early as day 13 in chicks, this study assessed video footage taken within a conventional, large commercial US chicken hatchery to identify potential animal welfare problems. Numerous incidences of serious animal welfare problems were evident. These included blunt force trauma, injured embryos and chicks, live chicks having been passed through a washer of scalding water, live chicks trapped in machinery, malfunctioning machinery, chicks falling from the conveyor belt, avoidable deaths, dead chicks, and an absence of humane euthanasia. Less acute, yet still serious, welfare concerns arose from high stocking densities and high-speed conveyor belts.

Risks of such welfare problems within chicken hatcheries are already highlighted within scientific and industry literature, with solutions heavily emphasized—such as machinery being specially designed with high sides to prevent chicks straying, and injuries and culls being monitored with resultant plans being implemented to mitigate culling and injury risks.

It is likely that problems identified within this hatchery are prevalent within many modern, commercial chicken hatcheries. Accordingly, animal welfare assessments should be conducted across all chicken hatcheries, with plans created and implemented to eliminate and minimize avoidable animal welfare problems and risks.

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Acknowledgments

The authors acknowledge the use of the Perplexity Large Language Model (free plan) on 31st October 2025 for paraphrasing parts of the introduction to avoid self-plagiarism of another recent study by the same authors (Mace and Knight, 2025) on chick capacity for suffering.

Conflicts of interest

The authors have no conflicts of interest to declare.

Funding

The authors declare that Animal Equality USA partially funded the research that this paper is based on. The Representing Animals Foundation also funded publication. Funders played no role in study design or analysis.

Author contributions

Conceptualization, J.L.M., A.K.; formal analysis, J.L.M.; investigation, J.L.M.; methodology, J.L.M., A.K.; project administration, J.L.M.; resources, A.K.; supervision, A.K.; writing, original draft, J.L.M.; writing, review and editing, J.L.M. and A.K. All authors have read and agreed to the published version of the manuscript.

Data availability

The primary footage analysed in this paper is fully cited within the study and available at: https://animalequality.org/campaign/end-factory-farming/baby-chicks-factory-farms. Occasionally, a longer piece of footage is referred to. This is made explicit in the study where this is the case. This longer footage can be made available on request.

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Supplementary Material – Examples of animal welfare problems identified in the video footage

Note: Timestamps are visible in the figures below. Unless otherwise stated in the figure captions, all screenshots are taken from the footage available at Animal Equality (2024a).

Fig. S1. A seemingly dead and maimed chick after having been put through the washer, presumably alive.

Fig. S2. A dead chick caught in machinery.

Fig. S3. A (dead) chick’s limb stuck in a basket.

Fig. S4. A dead chick in a crate.

Fig. S5. A dead chick found on the floor.

Fig. S6. A dead chick in water.

Fig. S7. Several chicks stuck (alive) in machinery.

Fig. S8. A chick still alive after having been put through the washer.

Fig. S9. Live chicks who have escaped the conveyor belt, now in a separate compartment.

Fig. S10. An injured/dying chick in a crate (barely moving).

Fig. S11. Crates crashing and mass embryo casualties.

Fig. S12. A live wet chick found on the floor.

Fig. S13. A mix of already dead and still alive embryos and chicks in bins/crates—the latter of whom are not receiving prompt euthanasia.

Fig. S14. An injured chick who is barely moving (cause unknown).

Fig. S15. Defective equipment. Note: This is from the full length footage and did not feature in the abridged version.