A Review of the Halal Poultry Slaughtering from Welfare and Legal Perspectives: Analysis of Research Results

The subject of halal slaughtering is one of the most widely discussed issues of animal cruelty and animal welfare in the public sphere. The discrepancy in understanding the contemporary and religious laws pertaining to animal slaughtering does not fully publicize to Islamic and Muslim ma-jority countries especially with respect to interpreting the use of stunning in animals. The electrical stunning is the cheapest, easiest, safest, and most suitable method for slaughtering that is widespread and developed. However, stunning on head of poultry before being slaughtered is a controversial aspect among the Islamic sects due to regulations of the European Union and some other countries. The current review highlights the instructions of halal slaughtering, legal legislation, and the effect of this global practice on poultry welfare and the quality of produced meat.


INTRODUCTION
It has been stated that Muslims will constitute approximately 30% (2.8 billion) of world population and their ratio in Europe will range between 5.9% to 10% by 2050. 1 Undoubtedly, an increase in the Muslim population will cause an increase in demand of halal meat and other products in global markets. It was found that halal meat is not only needed on the basis religious issues but also for community and commercial interests. 2 Historically, welfare of poultry has been a public interest since the legislation of human law. 3 In the last decades, there has been a widespread development in poultry industry depending on the account of accurate control of various factors including management, welfare, 4 and slaughtering systems. 5 Slaughtering is precisely defined as killing of animals for getting meat by various methods such as chemical materials, gases (carbon dioxide), electrical stunning, mechanical stunning (manual neck breaking) or decapitation, whatever slaughtering way is used, the birds must be desensitized during killing. 6 In poultry, electrical stunning is globally acceptable, 7 and the most widely performed stunning method in halal slaughtering important for high production level. 8 Traditional slaughter procedures have dealt basically with aspects that secure both safety and qualitative characteristics of the meat. In this regard, the safety indicates both the physiological and psychological attributes of the meat including wholesomeness, religious and aesthetic concerns. 9 Around the world, cultures and religions use many slaughter methods, among which commercially common are halal (lawful) and kosher (ritually pure) methods conducted by Muslims and Jews respectively. 10 These two procedures of slaughtering affect meat quality during pre-slaughter, slaughter, and post-slaughter stages with respect to tactile, aesthetic, masticatory, nutritional, soundness, convenience, and environmental profiles. 11 Law of humane slaughter of animals is adopted in most developed countries. These laws are regulated to ensure that animals are desensitized, unconscious and killed quickly and harmlessly before being slaughtered. 12 Based on these laws, poultry must also be electrically or gaseously stunned before killing with practical, economic, and safe way for personnel. 13 This review aims to explore the influences of halal poultry slaughtering method and its practice in poultry commercial operations with special emphasis on welfare and legislative laws as well as impacts on meat quality.

CONCEPT AND REQUIREMENTS OF HALAL SLAUGHTERING
Halal is an Arabic universal word which means lawful or permitted, and unlike halal is haram, which means forbidden, prohibited or unlawful. 14 The Arabic word of halal slaughter is Zabiha which means animal carcass after being killed according to Islamic ritual slaughter or Islamic criteria for meat production. 15  animals slaughtered without the name of Allah, animals with long pointed tusks or teeth, primates, amphibians, reptiles, donkeys, mules, insects, aquatic animals harmful to human, and animal blood and food mixed with or processed from blood. 16 All the guidelines concerning multiple steps of halal poultry meat production are derived from the Noble Quran, the sayings of Prophet Muhammad peace be upon Him (Hadiths or Sunnah), and doctrines. 17 Halal principles are mentioned in the Quran mostly in the chapters under the title Al-Baqarah (The Cow), Al-An'am (The Cattle), and Al-Maidah (The Table Spread). One example of what was stated in the Quran regarding that: "O mankind! Eat of that which is lawful and wholesome and follow not the footsteps of the devil. Lo! He is an avowed enemy of you". 18 N.G. Gregory 19 stated that the removal of the whole blood and preventing the delivery of blood to brain quickly is the main concern in humane slaughtering of animal. Besides, the stopping of flowing blood is important because it is considered as impure material from the Judeo-Islamic point of view.
The halal slaughtering action starts with making an incision under the glottis on the neck. Then, throat cutting is done to cut the esophagus, trachea and major vessels (carotid arteries and jugular veins) without head removal or severance spinal cord in the procedure 20 as shown in Figures 1 and 2. The cutting knife strokes the neck with three single directions at maximum with different depths on neck for each chicken as shown in the schematic diagram ( Figure 3).
The religious guidelines for halal slaughtering of poultry using manual or mechanical methods have been stated by the Department of Standards Malaysia: 21 1. Slaughtering must be performed by a Muslim butcher of sound mind and maturity. Also, it may be done with permission by women or followers of other faiths (Christians and Jews) who understand the fundamental rules   3. Humane treatment during handling and group the birds gently in transportation cages and lairage. Also, birds must be calm before being killed though preventing to expose birds into high intensity of light. 4. Efficient supply for feed, water, and ventilation to birds during transportation from farm to slaughterhouse especially during heat stress time. 5. Animal must not be restrained and shackled after neck cutting. 6. The gentle handling must be taken into consideration while the bird is being slaughtered, and prevention the painful handling which can causes legs bruises during shackling in slaughterhouse. 7. Animal killing is done only by neck cutting with stunning on head to kill.
However, death in chickens may result from stunning. 8. Profusion of blood flow following the neck cutting. 9. Commitment to recite tasmiyah (In the Name of Allah) loudly on each individual bird without any noise to allow hearing it. Moreover, it is not allowed to slaughter in the name of anything or anyone except Allah. 10. Using sharp slaughtering knife that has no nicks or scratches with facing animal in the direction of kaaba during slaughtering. 11. Sharpening the knife must not be done in front of chickens to be slaughtered. 12. Severing major veins for high blood loss. 13. Killing of birds by suffocation in a scalding tank is prohibited. 14. Washing and packaging of processed meat in clean condition without adulteration with mixed blood and swine casings or any harmful or toxic substances.

HALAL SLAUGHTERING AND POULTRY WELFARE
Treatment of birds during slaughtering in the slaughter plant affects welfare. Therefore, the validity methods in postmortem inspection in case of finding the traumatic injuries in bird carcass can be influenced by welfare indicators such as handling, lairage, transport, loading, and stunning procedures. 22 The most common practices and events in producing poultry meat begin with the following gradual steps: Performing the hand slaughter without stunning to produce halal meat is unable to meet the high demand for meat production compared with high speed of standard processing procedures in slaughterhouses 23 where slaughtering is performed between 140 to 180 broilers per minute 24 One problem related to poultry welfare during no halal slaughtering is possibility of unsuitable incision of neck by a rotating blade in slaughterhouse that causes an undesirable influence of blood loss and animal torment. 25 As a consequence, some birds may bleed to death if neck is not cut appropriately after the birds regain their consciousness and suffer from cruel distress when entered into the scalding tank. 26 Thus, monitoring of accurate neck position while slaughtering by persons or through using closed-circuit television is effective to solve this problem. 27 The removal of blood as fast as possible and getting rid of the oxygen amounts delivered to the brain is the goal of effective and humane slaughtering. 28 Removal of blood following killing is an important thing due to its impurity and dangerous source of contamination from the Judeo-Islamic point of view. Using another method for killing birds in non-halal conditions such as head decapitation results in induction of asphyxia, suffocation, and prolonged death time due to disturbance of the nervous system while the halal method separates the jugular veins and carotid arteries and prevents this case. 29 Killing in non-halal way leads to distress in animal such as blood aspiration into the lungs. On the other hand, the halal slaughtering of animals without stunning before painful neck cutting and exsanguination is a controversial topic of many opinions and may interfere with welfare issue and meat quality.

HALAL SLAUGHTERING VS. ELECTRICAL STUNNING AND POULTRY MEAT QUALITY
Meat quality is an important topic in poultry industry. Halal meat production is an Islamic method to produce permissible or lawful meat based on religious way derived from basic principles of the Quran and the Hadiths. This practice should meet the administerial, economic, and health perspective all over the world. 31 In a comparative study between stunned and non-stunned poultry on meat quality, 32 it was found that stunned meat had higher protein solubility and tougher texture than non-stunned meat. Moreover, non-stunned meat showed lower lightness and yellowness values with higher redness and chroma values compared with stunned meat. In Halal slaughtering of animal, the whole blood can drain out of the carcass efficiently. S.M. Ibrahim 33 found that there was a decrease in contamination risk with food borne pathogens represented by coliforms, E. coli, salmonella in meat and sausages of broiler chickens slaughtered by halal method. Similar results were declared by S.AM. Ali 34 while making a comparison among three ways of slaughtering the male broiler chickens (Islamic traditional way, Islamic hanging way, and electrical stunning). They concluded that the best method to reduce the microbial count on the carcass was achieved by Islamic hanging way 48 and 96 hours postmortem and the high bled blood weight was recorded by the same method. Recently, it was shown that chickens subjected to slaughtering by Islamic rules contained less residual blood in the meat accompanied by lowered bleeding time and death time which led to a decrease in bacterial counts, consequently lengthened shelf life in postmortem stage.  " 2020, vol. 49(8), pp. 1947-1950. Pobrane z czasopisma Studia Iuridica Lublinensia http://studiaiuridica.umcs.pl Data: 21/09/2021 20:18:13 U M C S However, M.M. Farouk 36 mentioned that stun only head in halal pre-slaughtering prior neck severance has been implicated in poor meat quality such as slow decline in blood pressure, blood splash (ecchymosis) in many organs and muscles, in addition to hemorrhages, broken bones, bruising and skin discoloration in poultry carcass. Besides, the electrical stunning could cause low efficiency of bleeding, incidence of blood blisters and produce tough meat due to rigor mortis phenomenon. 37 Moreover, electrical stunning could induce muscular contraction, 38 incidence of red wing tips and hemorrhages of wing veins 39 with negative effects on meat quality and downgrading of boilers carcass. N.G. Gregory and L.J. Wilkins 40 noted the occurrence of inefficient bleeding and high hemorrhages followed by death case resulted from heart fibrillation (irregular heartbeat) of broiler exposed to high voltage of stunning. Similar results were achieved by V.A. Hindle et al. 41 with respect to lowering of carcass characteristics of ducks, hens, and broilers subjected to increased amperage during stunning. Nevertheless, it was observed that stunned chicken with low voltage did not influence blood loss 90 to 120 seconds (exsanguination time) although less early blood loss was recorded. In addition, S.M. Abeyesinghe et al. 42 stated that overhead line shackling of conscious birds whether it is applied in halal slaughtering or not is involved in considerable damage of final meat product, strenuous working, and offense to animal welfare.

U M C S
Karrar Imad Abdulsahib Al-Shammari 20 HALAL SLAUGHTERING VS. ELECTRICAL STUNNING AND LEGAL LEGISLATION For more than 1,400 years ago, the basic religious laws and regulations in halal meat production were legislated. 43 The spiritual quality of produced meat from point of view of Islam and Judaism is a topic of concern to meet the religious compliance of these religious communities. Thus, this topic is strongly related with traditional slaughtering of animal. 44 The legislative authorities of halal certification may differ in understandable explaining of this method which creates differences in requirements and standards. For instance, while electrical head-only stunning (reversible stunning) of pre-slaughter (prior to the neck cut) is allowed based on halal standards for some halal certifying authorities, others may not permit such procedure. 45 This is due to the belief that ecchymosis which occurs in many muscles of killed animals is positively correlated with electrical stunning of animal head. 46 Precise monitoring and elaborate standards are required for halal slaughtering to prevent the problems related to integrity of halal meat products. Therefore, many non-governmental organizations in some countries have legislated guidelines and standards regarding production of halal meat where use various stages in the slaughter operations (on farm, pre-slaughter, on slaughter and post-slaughter). These organizations and communities involve the following: 47 Only the Australian and Malaysian governments have their own monitoring for their pertaining agencies about halal meat production and integrity. For local and export products, only JAKIM oversees this issue while the Australian government has its monitoring system for halal exported only. HFSAA in the United States is one of the important authority for the halal certification and follow the education and monitoring issues for poultry farming and slaughter places, although absence the halal certification guidelines in a single standard. The Arab Gulf Cooperation Council's standard and CODEX Alimentarius was admitted by the United States Department of Agriculture (USDA) for supply halal slaughter as an essential role of their meat export policy. 48 The stunning of animal before slaughtering raises concerns about full performing for conditions of halal killing. Based on scientific Islamic concept, the stunned animal is not probably alive at the time of slaughter and thus blood is not completely drained out and some birds may reach in delay time for slaughter process. 49 Also, the currents of electric stunning will stimulate cardiac arrest which is correlated with occurrence of red wing tips in broiler and reducing the carcass quality. 50 To killing birds with minimizing the quality disadvantages and emphasize on drain out of whole blood, the alternative method used is to apply a stunning current through the bird's head only. The birds become insensible and unconscious after being stunned on head with pin electrodes and expose for 0.5 second to current 190±30 mA. 51 It was confirmed that after stunning, that is 11% of birds appeared its rhythmic breathing. Although, some stunned birds (15%) appeared its rhythmic breathing after neck severance, and 5% of birds recurred this reflex 30 seconds later. 52 However, the identification for absence of consciousness is not dependent on movement lack of rhythmic breathing in birds. 53 Increased levels of rhythmic breathing for stunned birds, it is might relate to inadequacy of electrical current U M C S Karrar Imad Abdulsahib Al-Shammari 22 which make differences in the stunning system. Therefore, to avoid the individual variation in resistance of stunning, the recommended current is 250 mA. 54 It was religiously suggested by the Department of Islamic Development Malaysia 55 that using 2.50-10.50 voltage for 3.00-5.00 seconds is recommended for broilers with weights ranged from between 2.40-2.70 kg.
There are different points of view among Islamic sects regarding stunning on head without inducing injury to birds, e.g., Malaysia accepted the idea while Pakistan refuses it. 56 The rejection in Pakistani society is on grounds that it is opposite to Islamic rules, which causes a painful induction and incomplete blood loss. Lying of animal on its left flank facing the Qibla is followed method of slaughtering in Pakistan because this way allows to maximal draining all blood while killing through the pressure of body on heart. 57 There is also an assumption regarding predetermined electrical stunning correlated with determined body weight for each bird, however, this may depend on bearing the current applied. 58 The Council Directive 93/119/EC of 22 December 1993 on the protection of animals at the time of slaughter or killing 59 applies to protective activities of animal reared for meat, fur or skin or other products during times of movement, lairing, restraint, stunning, killing, and slaughtering. It explains and focuses that animals shall be avoided from irritation, pain or suffering with its activity through those times. To ensure compliance with the conditions of this Directive, this is belong to function of competent authority which is the central authority of a Member State or other authorities that have been delegated vocational competence by the central authority. The practice of halal slaughtering is under speciality of the religious authority in EU (European Union) Member States which permit to monitor and apply the special provisions for this kind of animal killing according to religious conditions and under official supervision by veterinarian who oversee the slaughter action in slaughterhouse.
Based on stated in Article 2 of Council Directive 64/433/EEC, 60 the official veterinarian shall be appointed by the central authority of the EU Member States and he responsible on religious authority to carry out the slaughtering action. The Directive also shows that stunning procedure shall not implement to animals exposed to slaughtering methods illustrated by religious way, however, the slaughtering has to take place in a general slaughterhouse. 61 In England, there are further requirements for unstunned birds. Birds must be slaughtered in fast, uninterrupted movement with knife of sufficient size. 62 Statistical information indicated that have been high rates in the number of domesticated animals (sheep, goats and poultry) killed without pre-stunning since 2015 in the United Kingdom. 63 However, some European countries such as Iceland, Sweden, Denmark, Norway and Switzerland, and outside of the EU, e.g. New Zealand, considers the killed birds without stunning as illegal procedure. 64 Therefore, it was found that some countries within EU allow Muslim communities to practice their religious rites for killing without stunning animal before slaughtering and with legal dispensation. On the other hand, other European countries consider that as illegal practice and they would like to change the halal meat concept where the Muslim communities live in minor populations. This leads to various interpretations and creates different rules.