La industria del huevo. Gallinas en jaulas.

The Egg Industry

Aitor Garmendia FOr animal save movement
Legal review: Alice Di Concetto
Translator: Liz Tyson
Estado español / 2018 - 2022

According to data published by the Integral Animal Traceability System (SITRAN), the number of hens farmed by the Spanish egg industry is 56 million (SITRAN, 2022). Of the population destined for production, which amounts to 47 million birds, 34 million of them live in overcrowded cages (REGA, 2021).1, 2, note 1 This figure places Spain as second in the European Union (EU) with regards to the number of hens farmed under this system, with far higher numbers than the vast majority of other European member countries.2

Due to continuous pressure to produce eggs, overcrowding, and poor environmental conditions, hens exploited in industrial farming suffer multiple diseases and pathologies. Many of them die before reaching the slaughterhouse and their carcasses often remain on the floor of the cage for days, or even weeks, while live hens move around them.

Both the livestock industry itself and public authorities are aware of the realities that will be described as part of this report. These are not isolated cases; they are the inevitable consequences of the breeding and exploitation of animals on an industrial scale.

Hens exploited for eggs in one of the cages in the warehouse.

Hens exploited for eggs in one of the cages in the warehouse. 2021.

According to the Eurobarometer on the Attitudes of Europeans towards animal welfare, 67% of citizens stated that they would like to have more information about the conditions in which farmed animals are kept.3 However, deliberate obfuscation by the livestock industry combined with its lack of transparency frustrates consumers’ ability –and their right– to make free and informed decisions.

The industry knows the damage that a video or a photograph can cause to its business. In recent years, covert filming carried out by animal rights organizations and activists has succeeded in bringing their abuses out into the open and contradicting the carefully curated image they seek to project in their advertising and marketing campaigns. The industry operates without transparency, and it is unusual for farm owners to allow any kind of documentation of their facilities. Protocols to prevent the entry of undercover activists or the critical press to their farms are becoming increasingly strict.

Against all odds, and after unsuccessfully requesting access to several others, one of Spain´s largest egg producers authorized me to enter their facilities. Between the years 2018 and 2022, I visited its farms six times.

This work, carried out in collaboration with Animal Save Movement, aims to contribute
information to the growing social debate on factory farming and its implications. Most of the images presented —except when expressly indicated— have been obtained in buildings that operate caged management systems and are representative of the generalized standard by which factory farming of hens for egg production is carried out.

Hens exploited for eggs in one of the cages in the warehouse.

Short documentary EGG made with images obtained during the investigation.

The Spanish Egg Industry In Figures

The regulations governing the management of poultry farms distinguish two categories of farms depending on the destination of the eggs: those for production, whose purpose is to produce eggs for sale to the public, and those for reproduction —divided into several levels— whose purpose is to obtain fertile eggs for incubators, where hens used for laying are born.4

In Spain there are 1,473 farms dedicated to egg production with a total population of 47 million birds —a figure that has remained stable in recent years5— and 236 farms dedicated to reproduction, with a total population of 9 million birds.1 However, the official census of hens kept for egg production does not include the number of birds used for breeding2 and so the figures reported in media and publications are conservative, and do not correspond to all the hens being exploited, which amounts to more than 56 million birds. Absent from the data too are the millions of male chicks who, due to their lack of commercial value, are simply crushed or gassed at birth.

On January 1, 2012, European Community regulations came into force mandating, among other things, that farms increase the size of their cages (from 550 cm2 to 750 cm2 per hen).6 This meant changing all existing cages and, in the words of the Ministry of Agriculture, Fisheries and Food (MAPA), produced a «real restructuring of the production sector».7 Related to this, Brussels initiated proceedings against Spain for not complying with the regulations on time despite the fact that the EU Member States had more than 10 years to do so. Since then, the percentage of farms dedicated to production using caged systems declined by almost half, going from 60.5% of the total in 2013 to 31.61% in 2021. Even so, the number of hens living in cages still represents 68,6% of the total number of individual birds. In addition, there are now also more than 15 million hens farmed in alternative systems (free range, barn, and organic farming systems).

Spain occupies second place, behind Poland, with regards to number of hens exploited under caged systems; fourth – behind Germany, Poland and France – in terms of total number of egg laying hens, and third – behind France and Germany – in overall egg production.2

The Incubator – To Be Born Without A Mother

During the first weeks of life under non-exploitative conditions, the domestic hen (Gallus gallus domesticus) —a subspecies that encompasses the different strains used for meat and egg production— remains with their mother;8, 9 something which benefits their behavioral development.10 However, under farm and factory farming systems, hens are artificially hatched in incubators and raised without the opportunity to experience maternal bonding. This denial of needs increases the likelihood that they will develop stereotypical feather pecking, a serious and widespread welfare issue that causes pain, distress, and even death.10, 11Industrial hatcheries have also been identified as a cause of various problems which compromise the hens’ health. A comparative study carried out between hens born in industrial incubators compared to hens born in calmer and less noisy environments concluded that the levels of stress and fear are higher in the former.13Noise around hatching can also affect the behavioral development and cognitive bias of hens.13

Fertile eggs that reach the incubators are the result of a genetic selection process that involves three generations of birds: great-grandmothers, grandmothers, and mothers. This process begins in the selection farms, which are highly technical units where the birds with the best genetic aptitude (or those from the “purest” lines) are developed in order to serve the different sectors of the poultry industry. In these units, criteria such as the number of marketable eggs per bird, the conversion index, behavior, robustness, resistance to disease, or the uniformity of egg size, among others, are studied.14 In these farms the first generation of hens— the great-grandmothers, are initially exploited. By crossing them, the second and third generations— the grandmothers and the mothers – are gradually obtained. Both are exploited in the so-called multiplication farms. The mothers’ farms are the ones that finally supply the incubators with fertile eggs, from which the hens destined for laying are obtained.

This production flow supplies all breeding systems: organic, free-range, barn, and caged. All the hens come from industrial hatcheries and half of the hens that are born are ground up alive or suffocated by gas inhalation.

Day-old chicks which will become laying hens– they arrive at the farm at one, two or three days old.

Day-old chicks which will become laying hens– they arrive at the farm at one, two or three days old. 2022.

Maceration And Death By Suffocation

Birds intended for egg laying lack the speed of growth and fattening that birds intended for meat production have been bred to possess. For this reason, the egg industry discards male chickens as they have no commercial value. They neither lay eggs nor are they efficient for obtaining meat. A few hours after birth, the males are separated from the females by a procedure called sexing and are then killed. In 2021 alone, industrial hatcheries in Spain produced more than 90 million eggs and supplied laying farms with more than 38 million hens. The Ministry of Agriculture, Fisheries and Food (MAPA) does not know the number of male chickens that were exterminated but estimates that it will be a figure similar to the number of females born.15, note 2

The two most widespread methods for killing male chickens are asphyxiation by gas inhalation and being ground to death. Both are considered legal procedures in Council Regulation (EC) No 1099/2009 of 24 September 2009 on the protection of animals at the time of killing.16 In addition to the ethical considerations involved in killing animals due to their lack of commercial value, these procedures also undoubtedly compromise their welfare. This is explicitly recognized by the European Food Safety Authority (EFSA).17 Before the regulation mentioned above, European law did not authorize the shredding and suffocation of chickens by gas inhalation and there was uncertainty about the legal nature of these two practices.

In controlled-atmosphere killing, death occurs as a consequence of exposure to different gases (carbon dioxide, inert gases, or a mixture of both). The Humane Slaughter Association (HSA) recommends a 3-minute exposure. This method causes pain, fear, and respiratory distress.17

Slaughter by maceration is carried out with an apparatus fitted with «rapidly rotating mechanically operated killing blades or expanded polystyrene projections»16 that destroys the bodies of the chickens while they are still alive. The young chickens are thrown onto conveyor belts which pull them into to the crusher. If blade speed or numbers of birds on the conveyor belt are not the proper ones, birds may remain conscious and experience additional distress, pain, and fear.17

Due to pressure exerted by animal rights organizations, added to the growing social interest in the conditions in which animals bred for consumption are treated, technologies have been developed that allow the sex of embryos to be determined at very early stages of their development. Once the sexes are detected, the eggs with male embryos are removed from the incubation process and replaced by others. This prevents the birth of male chicks and their subsequent slaughter. These technologies are known as “in ovo sexing” and are already being implemented in some countries, such as Germany and France, where legislation has already been passed to prohibit the subsequent slaughter of unwanted male chicks.18, 19Similar legislative measures are also planned in Italy. The Italian Congress of Deputies recently voted in favor of the ban on the slaughter of male chicks from the end of 2026.20 

Side Effects Of Food And Water Deprivation

In industrial incubators, eggs hatch after 24 – 48 hours. The first newly hatched chicks remain in the incubator until the last ones hatch. After that, they are subjected to different treatments (sex determination, vaccination, classification, etc.) and are transported to the farm. The duration of this process varies, and depends on the time of birth, the management of the incubator, and the transport time. During this entire process the baby birds can be deprived of food and water. A report carried out by the University of Wageningen (Netherlands) at the request of the Government —following a complaint filed by the animal rights group Wakker Dier— found that food and water deprivation significantly increases the mortality of chickens during the first week of life. It also negatively affects their ongoing growth.21

Day-old chicks are introduced into the cages in the rearing warehouse.

Day-old chicks are introduced into the cages in the rearing warehouse. They remain in these cages until they are approximately 17 weeks old. 2022.

Day-old chicks are introduced into the cages in the rearing warehouse.

Day-old chicks are introduced into the cages in the rearing warehouse. They remain in these cages until they are approximately 17 weeks old. 2022.

Day-old chicks are introduced into the cages in the rearing warehouse.

Day-old chicks are introduced into the cages in the rearing warehouse. They remain in these cages until they are approximately 17 weeks old. 2022.

Day-old chicks in the rearing warehouse, just unloaded from the truck that brought them from the hatchery.

Day-old chicks in the rearing warehouse, just unloaded from the truck that brought them from the hatchery. 2022.

Recepción de pollitas de un día.

Reception of day-old chicks. The birds, which have just arrived from the hatchery, are introduced into the cages. They remain in the cages until they are approximately 17 weeks old. 2022.

Reception of day-old chicks.

Reception of day-old chicks. The birds, which have just arrived from the hatchery, are introduced into the cages. They remain in the cages until they are approximately 17 weeks old. 2022.

From The Hatchery To The Farm: Transporting Day-old chicks

After the selection and classification process, females are introduced into boxes at high speed, stacked one on top of the other, and transported by truck to the farm. Up to that moment, all the birds, regardless of the farming system they were bred for - organic, free-range, barn, or cage - have been subjected to the same processes.

Legislation on the welfare of animals being transported to livestock farms is common to all vertebrates intended for consumption and is contained in Council Regulation (EC) No 1/2005 of 22 December 2004 on the protection of animals during transport and related operations.22 Despite the fact that they are newborn animals, with immature physiology, and are exposed to many negative welfare impacts during these journeys,23 there is no specific legislation for the transport of day-old chicks —the name given to chicks of up to three days old—24 and the very act of transport can kill them.

The Guide to good practices for the transport of the Poultry, developed for the European Commission as part of an EU-funded project, advises that «dehydration and under nutrition are major causes of transport morbidity and mortality».25 The EC never modified the relevant associated regulation, so the application of the guidance remains purely voluntary.

The Exploitation Of Hens In Caged Systems

Modern hen farms are made up of multiple large, highly-technical buildings. Each one can house tens of thousands of birds in cages arranged along rows of varying heights. One of the largest breeding farms in Europe is located in Mainar (Zaragoza, Spain) and houses 250,000 young hens. In 2008, in Sinarcas (Valencia, Spain), La Cresta Poultry Group built a farm with the capacity to confine 150,000 hens. At that time, the number of birds on the La Cresta farm had already reached one million.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC. 2019.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC. 2021.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC. 2019.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC. 2018.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC.

Laying house under the system of enriched cages, as required by DIRECTIVE 1999/74/EC. 2018.

The young hens arrive at the farm at just one, two, or three days old and are placed in the rearing houses where they remain until they are approximately seventeen weeks old. During this stage, efforts are made to maximize their genetic potential under strict lighting, temperature, feeding, and vaccination programs.26 From there they are transferred to the laying sheds, where they are exploited for a period ranging from 55 to 95 weeks —depending on whether the production cycle is extended—until they are no longer productive. They are then sent to the slaughterhouse.

Until January 1, 2012, the European directive that regulates the conditions of hens kept within caged systems, called unenriched cage systems —required a minimum of 550 cm2 of surface area per hen— slightly smaller than the size of a piece of paper. From that time, the system changed and became known as rearing in enriched cages. Since then, the minimum surface area required is 750 cm2 (600 cm2 of which are usable surface) —slightly larger than the size of a piece of paper.6

The changes to this system resulted in no meaningful augmentation in space for the hens. In addition, captivity, deprivation of fresh air and natural light, cage structure, and overcrowding continue to compromise the birds’ health, welfare, and their very existence. In conditions free of exploitation, the average life expectancy of hens is between 5 and 8 years, they can live up to 20 years of age, and have even been known to live until 30.27, 28 On farms, in contrast, their life ends when they are no longer considered profitable, usually at around 72 weeks of age but this can be extended for up to 40 more weeks.29, 30 This happens under any of the breeding systems.

Hens exploited for the production of eggs under the cage system required by DIRECTIVE 1999/74/EC.

Hens exploited for the production of eggs under the cage system required by DIRECTIVE 1999/74/EC. 2021.

Alternatives To Caged Systems

Comission Regulation (EC) No 589/2008 of 23 June 2008 laying down detailed rules for implementing Council Regulation (EC) No 1234/2007 as regards marketing standards for eggs,4 establishes three alternative systems to farming in cages: [0] organic, [1] free-range, and [2] barn eggs. The number corresponds to the first digit of the code that appears stamped on the eggs from the relevant system. The number [3] corresponds to the cage production system, from which 89% of the eggs consumed in Spain (2019)7 come.

Organic egg production, one of the three alternative systems to cages.

Organic egg production, one of the three alternative systems to cages. 2018.

Organic egg production, one of the three alternative systems to cages.

Organic egg production, one of the three alternative systems to cages. 2018.

The parameters of the other systems are described as follows:

EFSA's Animal Health and Welfare Panel (AHAW) concluded in a report published in 2004 that alternative systems to cages also negatively influence the health of hens. They are more exposed to bacteria, parasites and infectious diseases; pecking is higher in large groups of birds and can cause tissue damage, cannibalism and mortality; levels of dust, microorganisms, and ammonia in the air are higher and can have harmful consequences for the respiratory system and eyes, and the mortality rate is typically higher than in cage systems.33

A Swedish study carried out between 2001 and 2004, which included 914 hens from 172 different poultry houses, showed that in free-range or indoor systems with litter, there was a significantly higher incidence of bacterial and parasitic diseases as well as cannibalism.34

Another study analyzed 1,479,036 hens housed in cage-free systems in Belgium between 2012 and 2013. At 60 weeks of age, the average cumulative mortality was 4.1%. The main causes were feather pecking and cannibalism, salpingitis (a bacterial infection), Escherichia coli infections, and suffocation. Of the 47 flocks, 46 had clipped beaks. Red mites were found in 63% of the hens houses.35

Problems Associated With The Exploitation Of Hens

The exploitation suffered by hens on farms has consequences for their welfare and health. A large number of them —in the EU, between 10 and 30 million a year—33, 36, 37 die before being transferred to the slaughterhouse and those that survive endure their suffering for longer only to be slaughtered in the end. The procedures to which they are subjected —such as the mutilation of their beaks or the clearing of birds from the farm— the overcrowding and exploitative conditions or the genetic pressure, among other factors, are the cause of different health problems that affect their well-being and quality of life. Below we delve into some of the more common issues and scenarios.

A dead hen, removed from the cage and thrown on the ground. A percentage of them -in the EU between 10 and 30 million a year- die before they are transported to the slaughterhouse.

A dead hen, removed from the cage and thrown on the ground. A percentage of them -in the EU between 10 and 30 million a year- die before they are transported to the slaughterhouse. 2019.

A dead hen, removed from the cage and thrown on the ground. A percentage of them -in the EU between 10 and 30 million a year- die before they are transported to the slaughterhouse.

Detail of the previous image. 2019.

Gallinas muertas, sacadas de las jaulas y arrojadas al suelo.

Dead hens, taken out of the cages and thrown on the ground. A percentage of them—in the
EU, between 10 and 30 million a year—die before being transported to the slaughterhouse.
2022..

[Detalle imagen anterior] Gallina canibalizada en un sistema de jaulas acondicionadas.

Every year, between 10 and 30 million hens die before they reach the slaughterhouse.
The bodies of many of them can remain on the floor of the cage, with the rest of
the living hens, for days or weeks. 2019.

[Detalle imagen anterior] Gallina canibalizada en un sistema de jaulas acondicionadas.

Every year, between 10 and 30 million hens die before they reach the slaughterhouse.
The bodies of many of them can remain on the floor of the cage, with the rest of
the living hens, for days or weeks. 2019.

Cannibalism

Feather pecking and cannibalism are very frequent phenomena in farms for birds destined for laying.38 The latter consists of one bird pecking, tearing, and eating skin, tissue or organs of another bird. Outbreaks of cannibalism occur under all breeding systems and occur in different species of birds (hens, ducks, turkeys, quail, and pheasants). Cannibalism can begin with feather pecking and is usually directed toward the body, toes, tail, and cloaca.39 There are, among others, multiple factors that can cause this behavior, including genetics, diet, system breeding, light intensity, temperature, humidity or lack of enrichment.40

In 1998, a cross-sectional study funded by the Ministry of Agriculture, Fisheries and Food (MAFF) in the United Kingdom was carried out to analyze the risk factors for feather pecking in hens kept in alternative systems to cages. 46.6% of the farmers reported that pecking was normal on their farm. 70% confirmed the existence of bald spots in the birds; 12% reported blood; 64% reported damaged feathers; 10% reported hens pulling out their own feathers; 49% reported hens pulling out the feathers of others; 58% reported pecking the feathers of others, and 17% reported feather eating. Likewise, 68% of the farmers observed damage to the backs of the birds; 57% to the necks; 55% to the tails; 27% to the cloaca; 23% to the head, and 10% to the wings. The total percentage of birds affected was 30%.41

Beak Mutilation

Beak mutilation is an industry-wide practice aimed at preventing mortality caused by cannibalism which, in addition to being a serious welfare problem also poses an economic threat to the farm.42 It is also carried out to minimize aggressive head pecking, pecking of the cloaca, and all forms of feather pecking, but fails to completely prevent these behaviors.43, 44 European legislation allows beak trimming in all farming and rearing systems: conditioned cages, barn, free-range, and organic.6, 45, 46 In conventional production systems, States are authorized to trim beaks «provided it is carried out by qualified staff on hens that are less than 10 days old and intended for laying».6 However, in organic farming systems it can only be done to birds of up to 3 days of age «if allowed by competent authorities, and only under certain conditions».31 Member States can also restrict this practice or prohibit it. This has happened in Sweden, Norway, and Finland.47 A large meta-analysis analyzing data relating to 176 million hens from 16 countries —ten of them in the EU— between 2000 and 2019, found that 84% of birds had mutilated beaks.37

Beak mutilation is a widespread practice throughout the industry aimed at preventing mortality caused by cannibalism.

Hen with its beak trimmed. Beak mutilation is a widespread practice throughout the industry aimed at preventing mortality caused by cannibalism. 2018.

The beak is a functional and complex organ endowed with thermoreceptors, nociceptors, and mechanoreceptors that the birds use to carry out many activities. The two most widely used beak mutilation procedures are hot knife cutting and infrared energy cutting, which is done in the incubator shortly after birth. Blade cutting is more aggressive, but both methods can cause pain (acute or chronic), damage tissues and nerves, cause neuromas, and compromise some functions necessary for the health and well-being of hens. These include feeding behavior, water intake, the grooming of the plumage by which mites and lice are eliminated, and exploration of their environment.43, 48, 49, 50, 51

Frustration Of Natural Behaviours

The new upgraded cages in use in the EU are similar to conventional cages (pre-January 1, 2012) and, despite the fact that they include a nest and perches, have not made a significant difference to hen welfare. The cage is a wire enclosure where the hens live crammed together. The height of the cages only just allows them to stand up. A study carried out at the University of California on the space required by hens for certain movements yielded the following results: 1,271.8 cm2 as the average area required to allow birds to turn (180º) and 1,693 cm2 as the average area required to allow the birds to extend and flap their wings.52 These figures are considerably higher than the minimum mandated by the European directive (600 cm2 of usable surface).

Top view of the cage required by DIRECTIVE 1999/74/EC.

Top view of the cage required by DIRECTIVE 1999/74/EC. 2018.

If they are given the opportunity, hens will actively use a larger amount of space.53 The structure of the cage and its dimensions limit and prevent the expression of natural behaviors necessary for the health of the birds, some of which are described below.54

Egg Production Pressure

The presumed ancestors of hens —the red jungle fowl— lay between 10 and 15 eggs a year, in contrast to the 115 eggs that a domestic hen laid in 1930 and the more than 300 eggs that genetically manipulated strains can lay today in industrial farming.70,71 This pressure on their reproductive systems predisposes them to various health problems.72, 73

Prolapse is one of the most common conditions suffered by laying hens in farms. It refers to the displacement of the oviduct and rectal organs out of the cloaca after laying. This condition causes permanent damage to the hen and can be fatal. In addition, exposed membranes can attract other hens to peck at the cloaca, leading to cannibalism.73

The first indication of a prolapse problem is the presence of eggs with blood-stained shells.

The first indication of a prolapse problem is the presence of eggs with blood-stained shells. 2019.

The formation of the eggshell demands a high level of calcium that comes, in large part, from the skeleton of the hen. The Farm Animal Welfare Committee (FAWC) —a body established by the British Government in 2011— points out in a report that a hen's need for calcium for egg production exceeds her body's reserves 30 times over.71 Different studies have associated egg production with bone weakness and fractures.62, 72, 74, 75, 76, 77, 78 The hens most affected experience difficulty standing and may eventually die due to inability to reach food or water. They likely also suffer from chronic pain and distress.71, 78, 79, 80 An investigation carried out in Denmark on 4,794 hens from 40 different flocks observed a prevalence of bone fractures ranging from 53% to 100% in alternative systems to cages and from 50% to 98% in enriched cage systems.81 Another study conducted in the UK found fractures in 36% of enriched cages and 45% to 86% of alternative systems.71

Foot Conditions

In alternative systems to cages, bedding material is provided for birds. It can be made of wood shavings, sawdust, rice husks, straw or other elements and prevents the birds from stepping on the ground. Unlike caged systems, the places that house these birds lack conveyor belts for the removal of droppings, feed waste, or feathers. The birds live on this mixture of bedding and waste product during their entire productive cycle, which ranges from 55 to 95 weeks.29, 30 The humidity and high ammonia content of the litter can cause plantar dermatitis and lameness.82 If severe, it can lead to bulbous lesions and painful inflammation that severely affects the welfare of the hen.83

The floor of the EU-regulated enriched cages is sloped and made of wire. Its structure may end up having consequences for the health of the hens.

The floor of the EU-regulated enriched cages is sloped and made of wire. Its structure may end up having consequences for the health of the hens. 2021.

Hyperkeratosis (hypertrophy of the outer layer of the skin) occurs on the toes and feet of caged hens. It is caused by a greater compressive load from the ball of the foot on the wire floor of the cage, as well as on the perch.81, 84, 85, 86 Likewise, in the cage, which lacks substrate to keep claws maintained through scratching, they can grow too long, thus breaking more easily and leading to open wounds and increased susceptibility to infection.85 They can also damage the skin of other birds.33

Artificial Light

Vision is an important sense for the well-being of birds.87 Their visual acuity is superior in relation to other groups of vertebrates and they are capable of perceiving not only the range of light visible to humans, but also light which falls within the UV range, in addition to being able to detect polarized light and magnetic fields.88 The search for food and water, movement or the recognition of their conspecifics are visually mediated behaviors that can be affected by the lighting conditions of their housing.87, 88, 89, 90, 91, 92 Light also affects many other essential functions, including body temperature and metabolism.91

Artificial lighting conditions in the aisle of one of the warehouses. The European directive states that the warehouses must be lit “in such a way that the hens can clearly see each other and be seen clearly.”

Artificial lighting conditions in the aisle of one of the warehouses. The European directive states that the warehouses must be lit «in such a way that the hens can clearly see each other and be seen clearly». 2018.

The European directive indicates that housing must be illuminated «to allow all hens to see one another and be seen clearly, to investigate their surroundings visually and to show normal levels of activity». 6 However, artificial lighting systems in poultry farms do not address the functional development of birds' visual abilities92 and are implemented to stimulate and prolong their reproductive activity, thus maximizing the farm’s production.93, 94, 95, 96, 97, 98 A poor correlation between the light provided and that required for effective vision can cause distress and affect the welfare of hens.92 In addition, the way in which light is managed can predispose hens to severe feather pecking, cloacal cannibalism, and early mortality.46

The End Of The Laying Period

The end of the laying period signals the last stage in the hens’ lives, when their egg production declines and it is estimated that the birds have fulfilled their productive function. This occurs at generally around 60-70 weeks of age. It is then that they are taken from the farm and slaughtered. The livestock industry refers to this as “culling”.

The bodies of the spent laying hens might be used for meat for human consumption, for oils or protein meals for other animals, for fertilizers, for functional food ingredients, other uses, or they may simply be thrown away.99

In 2021, more than 34 million hens were slaughtered and used for human meat consumption in Spain alone.100

Depopulation

To avoid the risk of spreading diseases from one bird to another, Spanish Royal Decree 637/2021 requires depopulation to be carried out using the all-in-all-out system.4 This occurs when the production cycle has ended or when birds are transferred from one facility to another. In these cases, the farm must be completely emptied of birds. Once the process is finished, the farm is disinfected, and a new flock of hens is introduced.

Overcrowding in the transport cages is very common. This is how they are put into trucks and transported to the slaughterhouse. Some do not survive the trip.

Overcrowding in the transport cages is very common. This is how they are put into trucks and transported to the slaughterhouse. Some do not survive the trip. 2018.

When egg production has peaked and begins to decline, the birds are considered to have fulfilled their productive function, they are removed from the farm and killed.

When egg production has peaked and begins to decline, the birds are considered to have fulfilled their productive function, they are removed from the farm and killed. 2018.

The process of clearing is difficult to record. While the clearing of male chicken farms has been brought to the public’s attention by animal rights organizations on various occasions, the same has not happened with the clearing of female chicken (hen) farms. This is not just because of the airtight nature of livestock farms and the fact that this process is particularly violent, but also because the estimated productive cycles for hens are considerably longer —between 55 and 95 weeks for hens compared to 6 for male chicken farmed for their flesh— and clearing takes place less frequently.

EC Directive 1999/74 mandates that the dimensions of the cage allow the birds to be removed «without undergoing unnecessary suffering or sustaining injury».6 In addition, EC Regulation 1/2005 prohibits: «a) strike or kick the animals» and «d) lift or drag the animals by head, ears, horns, legs, tail or fleece, or handle them in such a way as to cause them unnecessary pain or suffering». 22 Despite this, the law does little to protect animals in practice. Clearing is carried out at high speed and a single operator can remove 10,000 birds in one day — between 10 and 20 individuals per minute.101 This rate makes it impossible to meet the demands of the law. In addition to stress and fear, many hens receive blows to their heads, wings, and other parts of their bodies, are violently grabbed by their feet, and suffer broken bones.101

Once they are removed from the cages, the hens are placed on the shelves of a cart, even smaller than the cage, and are then transferred to the truck. In this new space they cannot stand up and the overcrowding is such that, in order to close the compartments, they are crushed against one another.

Hitting animals, causing them "unnecessary suffering" or crushing them against one another is in breach of European regulations. However, the law does not require the presence of any veterinary inspector to assess welfare standards. During the process that I witnessed, the way in which the hens were treated was unsupervised.

e) the personnel handling animals are trained or competent as appropriate for this purpose and carry out their tasks without using violence or any method likely to cause unnecessary fear, injury or suffering;

Council Regulation (EC) No 1/2005 of 22 December 2004 on the protection of animals during transport and related operations.22

During the clearing of the farm, many hens receive blows to their heads, wings and other body parts, they are violently grabbed by their legs and suffer broken bones.

During the clearing of the farm, many hens receive blows to their heads, wings and other body parts, they are violently grabbed by their legs and suffer broken bones. 2018.

Transport

Transport to the slaughterhouse is a particularly critical stage of the process102 that involves almost all of the animals that are exploited on farms excluding, of course, those who die before this point. European regulations authorize journeys of up to 24 hours without rest for pigs and horses; 14 hours for goats, sheep and cows, and 12 hours for birds and rabbits.22

In the case of hens, transportation is «extremely stressful».103 he birds are suddenly moved to a new environment where they have little space and can be deprived of food and water for 12 hours, as permitted by law.22 During the process—including catching, loading, and unloading at the slaughterhouse—they can suffer bruises, broken bones, wounds, heat stress, dehydration, and even death.104 A study conducted in the Czech Republic between the years 2010 and 2017, which monitored the transport of 17,436,074 hens, found a mortality rate of 0.516% (89,970 hens).104 Another study carried out in Great Britain on 13,300,000 hens during 2009 by the UK's Meat Hygiene Service found a mortality rate of 0.27% (35,910 hens).104

Carga de gallinas en el camión que las transporta de la explotación al matadero.

Loading hens onto the truck that transports them from the farm to the slaughterhouse. 2018.

Durante el proceso de carga, las gallinas pueden sufrir hematomas, fracturas de huesos, heridas, estrés térmico, deshidratación e incluso la muerte.

During the process—including capture, loading, and unloading at the slaughterhouse—they can suffer bruising, bone fractures, wounds, heat stress, dehydration, and even
death. 2018.

Despite the fact that transport is one of the most delicate and vulnerable moments for birds, the health of the animals remains in the hands of the carriers and not official veterinary inspectors or specialists independent of the farming industry.

Welfare conditions of animals during transport result mainly from the day-to-day conduct of the transporters.Checks by competent authorities may be hindered as transporters can freely operate in different Member States. Therefore, transporters should be more accountable and transparent concerning their status and operations.

Council Regulation (EC) No 1/2005 of 22 December 2004 on the protection of animals during transport and related operations.22

On the other hand, the number of inspections that are detailed in the National Program for the official control of animal welfare in livestock farms and the transport of animals is insufficient. If a slaughterhouse receives 100 trucks, one inspection is required; if it receives 5,000 trucks, four inspections are required and if it receives more than 18,000 trucks, ten inspections are required. During loading, if the trucks are going to other countries, two checks are required for a number of shipments less than or equal to 100 and four checks for a number greater than 100105

The reality behind these figures reveals that tens or even hundreds of thousands of trucks carry out loading, transport and unloading outside of any official veterinary controls. Animals can suffer harmful treatment at the hands of carriers or operators —as the images presented in this report clearly demonstrate — beyond what is permitted by law, with total impunity.

A hen that died during the clearing and loading process.

Dead hen in the aisle of one of the farm's sheds.

The Slaughterhouse note 3

The livestock industry maintains that stunning methods applied to animals prior to slaughter prevent their suffering. In addition, it ensures that welfare regulations are strictly adhered to. None of this is true.

In recent years, I have visited dozens of slaughterhouses —for rabbits, birds, horses, lambs, pigs, and cows— and published two papers that delve into these issues: one documented 58 slaughterhouses located in Mexico and another a further 16 slaughterhouses located in Spain. In them, I have been able to verify that the law is not complied with and that animals suffer different forms of violence inherent to industrial slaughter processes.

Council Regulation (EC) No 1099/2009 of 24 September 2009 on the protection of animals at the time of killing recognizes that «killing animals may induce pain, distress, fear or other forms of suffering to the animals even under the best available technical conditions».16 Likewise, investigations carried out in slaughterhouses around the world using hidden cameras corroborate these facts. It is easy to verify this using a simple internet search - there are hundreds of videos that show the systematic breach of the law and the innumerable harms suffered by animals.

Slaughter of a chicken in the bleeding area at the poultry slaughterhouse.

Slaughter of a chicken in the bleeding area at the poultry slaughterhouse. 2018. / Representative image of the slaughtering process of hens designated for egg production.

Council Regulation (EC) No 1099/2009 defines stunning as «any intentionally induced process which causes loss of consciousness and sensibility without pain, including any process resulting in instantaneous death». The methods permitted in the EU for the stunning of birds are as follows: penetrative and non-penetrative captive bolt device (severe brain damage); firearm with free projectile (severe and irreversible damage of the brain); cervical dislocation (cerebral ischemia); percussive blow to the head (severe brain damage); head-only electrical stunning (generalised epileptic form on the electro-encephalogram); head-to-body electrical stunning (generalised epileptic form on the electro-encephalogram and the fibrillation or the stopping of the heart); electrical waterbath (generalised epileptic form on the electro-encephalogram and possibly the fibrillation or the stopping of the heart) and exposure to various gases (unconsciousness followed by death from anoxia).16

According to a study published in 2012 by the Commission's Directorate-General for Health and Food Safety, the vast majority of hens intended for hens destined for laying were stunned using an electric water bath (83%). In Spain, all the hens, 44 million, were stunned using this system.106 The method and the issues associated with it are explained below.

Chicken hanging from shackles on a conveyor belt.

Chicken hanging from shackles on a conveyor system. 2018 / Representative image of the slaughtering process of hens designated for egg production obtained during an investigation with Nor.

Stunning By Electric Waterbath

A common element of slaughterhouses is the aerial conveyor system. It consists of a rail system that moves the animals suspended from their legs through all areas of the slaughterhouse. This facilitates production line efficiency and speed.

The poultry slaughterhouse conveyor belt runs constantly and at high speed. Some lines can kill more than 8,000 birds per hour. Birds are removed from transport cages, manually hung by their legs on the hooks of the conveyer and carried to an electrified water tank. The water level must be high enough for the birds’ heads to be submerged.16 Once they enter the tank, the conveyer drags them through the water through which an electrical current circulates. The law requires that the stunning system guarantees immediate unconsciousness and that this state last until the death of the animal. However, this is not always the case. Some chickens avoid submerging their heads by lifting them and manage to pass above the tank without being electrocuted. On other occasions, the application of electricity is not sufficient or the stunner is blocked due to a breakdown —the law assumes these circumstances as possible.16 As a result, millions of chickens are conscious when they are slaughtered.

Both during the loading process on the conveyor and in the electric water tank, birds can experience broken bones, physical pain and suffering. This is stated by the EFSA Technical Committee on Animal Health and Welfare (AHAW) in an opinion published in 2004:

Electrical stunning and electrical stun / killing using water baths require extremely stressful handling and shackling of live poultry. The pain and distress associated with inversion (hanging upside down) and shackling (compression of metatarsal bones) induces wing flapping in the majority of birds, and there is a potential in a significant number of animals for dislocations and fractures to occur.

Hanging upside down on shackles is a physiologically abnormal posture for poultry and compression of metatarsal bones by the metal shackle is extremely painful, and hence, induces wing flapping (Gentle and Tilston, 2000).

Nevitably, the pain and distress induced by shackling causes severe wing flapping which, in turn, increases the prevalence of dislocated joints and broken bones (Gregory and Wilkins, 1990a; Gregory et al., 1

Opinion of the Scientific Panel on Animal Health and Welfare (AHAW) on a request from the Commission related to welfare aspects of the main systems of stunning and killing the main commercial species of animals.107

Once the hen has passed through the electrified water tank, she reaches the slaughter area, where her throat is cut. European regulations require that the cut be made in both carotids.16 For this, an automatic cut-throat or a sharp knife can be used. In 2011, the EFSA issued another opinion where it recognized that at least 4% of birds —which translates into millions of hens, chickens, turkeys or others— were conscious at the time their throats were cut. It also indicated that slaughterhouse operators tend to reduce electrical current —and thus its efficiency— for reasons related to meat quality.108 If animals remain conscious during bleeding or arrive alive in the scalding tank, they may feel pain, fear and anguish.109 In the chicken slaughterhouse where the images that accompany this section were recorded, some birds continued to show signs of consciousness after the slitting of their throats —it can be seen in this report starting at minute 14:40.

Eggs: Abuse, Exploitation, And Death

The egg industry, through labels that appeal to the idea of good welfare for the hens, to their presumed «humane treatment», or to their farmed conditions —for example the promotion of «cage-free» eggs110, 111— tries to confuse consumers by making them believe that on their farms and in their slaughterhouses, the hens are well treated and that the current production of eggs is the natural result of this nurturing environment.

Likewise, in their advertising campaigns, they make use of images that do not correspond to their facilities and that are far from the real spaces where the hens live, suffer, and die.

Batería huevos granja

Gallina muerta en el pasillo de una de las naves de la explotación.

As has been seen, regardless of the breeding system —conditioned cages, barn, free-range, or organic — all commercially bred hens suffer the exploitation inherent to livestock processes. From the moment they are born in the incubator trays until they are transported to the slaughterhouse and brutally killed, they suffer damage that compromises their physical and psychological health.

The abuse suffered by hens, as well as other animals used for food production —pigs, cows, hens, fish, and others— would not be accepted if they were committed against dogs or cats, for example. In fact, under the current laws of many countries, these abuses would be considered crimes punishable by imprisonment.

If we accept the consumption of eggs as part of our diet, we have to assume our complicity with the abuses described here. There is no one without the other. Abuse, exploitation and systematic death are inherent to the consumption of eggs.

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NOTES

Note 1 / 09/26/2022 / Consultation made to the Ministry of Agriculture, Fisheries and Food and answered by email by the General Sub-directorate of Livestock and Hunting Production.

«It is correct to consider the population of laying hens at 47 million [...] based on the census data obtained from REGA. This census is reported by the producers based on the obligation to report – per each breeding system – in accordance with the regulations (RD 479/2004 and RD 637/2021 on the management of poultry farms) to the CCAAs, which then pass it to REGA. The figure of 52 million hens (SITRAN) includes rearing farms [...] (subsequently they go into production) and is data which is subject to change».

Note 2 / 09/26/2022 / Consultation made to the Ministry of Agriculture, Fisheries and Food and answered by email by the General Sub-directorate of Livestock and Hunting Productions.

«When we say that there is no 'exact number' of slaughtered male chicks, it means that there is no exact record of their number, but an estimate can be made, since approximately 50% of hatched chicks are male, so if 38,937,372 chicks are born, we can estimate that the same number is the male chicks slaughtered».

Note 3

The stunning and killing methods are applied and executed similarly for both chickens and hens. Given that chickens destined for the meat industry constitute the vast majority of birds exploited and killed, and due to the sealed nature of slaughterhouses and the difficulty of accessing their facilities, the chances of documenting the slaughter of hens are very low. Therefore, the images presented at this point come from a chicken slaughterhouse. All of them are representative of the slaughter of chickens. Both chickens used for meat production and hens used for laying are part of the same species and the methods used in their slaughter are the same.