Animal slaughter for human consumption is regulated worldwide by different legislations to safeguard the animal welfare facet of the process; all those various laws and acts are meant to ensure that the animals are slaughtered in a hygienic environment and in a humane way. However, in many countries including democracies like the USA^1,2, UK³ and India⁴ (in some of the states), these very legislations exempt religious animal slaughtering practices from following the humane aspect of this process, which is a fundamental deviation from the standpoint of animal welfare. Now, as per the estimation of the ‘State of Global Islamic Economy’ (2016/17), the Halal certification is a 2.1 trillion-dollar industry⁵; and this statistic perhaps explains why this exemption is allowed. Animal welfare is a continuing evolutionary notion⁶ and yet it doesn’t fit the mould of an essentially contested concept⁷. Thus, the idea of animal welfare in its present form is not absolute and needs more deliberation to reach an optimal definition.  

Globally, two of the most wide-spread religious animal slaughter methods are kosher (aka shechitah) and halal (aka dhabihah); technically they are different names of the same process followed by Jews and Muslims, respectively. Jhatka slaughter process is traditionally followed by the people of two of the Indic religions, viz. Hinduism and Sikhism. India, being the homeland of around 200 million Muslims, observes a huge number of halal slaughter throughout the year especially during their festival of sacrifice. Theoretically, only healthy animals qualify for sacrifice in religious slaughter. During, kosher or halal slaughter, a sharpened knife is used at the ventral (front) portion of the neck of the animal and using only a single cut (with multiple strokes without lifting the knife) the trachea, oesophagus, carotid arteries, jugular veins and vagus nerve are truncated8 to allow the blood to drain out of the body till the animal dies. This ventral neck incision (VNI) method ensures that the spinal nervous system is intact till the death of the animal. In contrast, during jhatka way of slaughter, the cut is made at the dorsal (back) side of the neck to dislodge the entire spinal column from the skull; in this way it not only leads to cervical dislocation but also decapitation (beheading) in a single blow and hence a heavier sharpened object is used for this. 

Now, to compare these two methods, we will the take help of standard scientific knowledge and literature to evaluate which one of them is more humane and ethically recommended from the standpoint of animal welfare: 

a. Normally, any sensation felt in our body (somatic cells) is first perceived by cognate receptor proteins and it is then transmitted by nerves (collection of neurons) through the spinal cord to the brain. The response from the brain again is transmitted through the neurons of the spinal cord and manifested by the effector muscles of the body. In case of halal slaughter, this spinal nerve pathway is purposely not disturbed while in case of jhatka it is disrupted instantly; hence, the sensation of pain is bound to be lost immediately in the jhatka method while in case of halal, the pain sensation is transmitted from the brain until the animal dies.  

b. One of the most well-accepted ways to measure pain is the EEG (electroencephalogram) or the study of neuronal electrical response in the brain. Docile animals like cow and sheep do not always visibly exhibit their pain; EEG study works perfectly to unearth their sensation of pain. Scientists have shown that within 5-10 seconds of cervical dislocation (occurring during jhatka slaughter), the function of the cerebral cortex (brain) stops⁹. Similar studies by French investigators for ventral neck incision (committed during halal slaughter), have shown the cattle to exhibit pain response up to 60 seconds and sometimes for minutes^10,11. And if the cut is not successful during halal, the animal undergoes unbearable pain¹². The reason behind this suffering is twofold: primarily, the nerve connection through spinal cord is intact and secondly, the vertebral arteries that also supply blood to the brain are unaffected during halal slaughter¹³.  

In contrast, during the jhatka way of slaughter, both the neural and blood vascular connection is instantaneously disrupted, as a result, no oxygen is supplied to the brain and hence, the animal post-decapitation, almost immediately, completely loses consciousness¹¹. VNI instigated during halal slaughter causes ‘noxious stimulation’¹⁴ and contributes to a significant increase in the feeling of pain in the animal under slaughter as per the studies of Australasian and British groups of researchers^15-19.  

c. In USA majority of the state animal welfare regulatory authorities recommend single blow slaughter for cow, pig and other cattle1 along with slaughter followed by stunning (a rapid mechanical or electrical method to cause immediate deprivation of consciousness)²⁰. Euthanasia (ethical planned killing) by decapitation produces prompt, painless unconsciousness in laboratory rodents²¹. According to AWA (Animal Welfare Act) and PHS (Policy of Humane Care and use of laboratory animals), cervical dislocation and decapitation are scientifically and ethically approved methods of animal euthanasia while ventral neck incision is only recommended post gas-stunning (using a high concentration of carbon-di-oxide) or anesthesia²². For laboratory animals, these rules are followed across the scientific fraternity worldwide.  

d. Different groups of researchers across the globe have time and again provided evidence to prove that during the kosher/halal way of slaughter, animals undergo an immense amount of stress; in case of cows/bulls and goats, the level of three stress hormones, viz. cortisol, nor-adrenaline and dopamine increase 30-50%^23-25. This occurs because the release of most of our hormones, including all the stress hormones, are neuronally controlled by hypothalamic secretions from our brain.  

Pioneering work of famous American scientist Temple Grandin shows that if slaughter is performed without stunning, blood cortisol level increases followed by an increase in the muscle temperature of the animal^26,27. Normally, moderate level of adrenaline secretion as a response to stress converts muscle glycogen into lactic acid which lowers the meat pH (makes it acidic) and this not only keeps the meat tender and pinkish in colour but it also protects from the growth of harmful bacteria. But with the stressful slaughter method, excess secretion of the same hormone quickly causes depletion of the total pool of muscle glycogen; hence, by the time the meat is marketised, no more lactic acid is left in it, causing a higher pH level which promotes bacterial growth with drier, darker and firmer meat quality²⁸.  

Moreover, most of the stress hormones (except adrenaline) are steroid in chemical nature and thus can traverse to the cell membrane directly to bind with nuclear (DNA) receptors causing irreversible genomic changes to the cell^29,30; the effect of this interaction could be long lasting even after complete removal of the blood from the body of the slaughtered animal.  

A similar phenomenon has been observed in case of sheep meat where researchers found that artificial injection of stress hormones destroy the texture and taste of the meat31. Probably due to a lower stress response during decapitation (jhatka), a similar study conducted by the National Institute of Mental Health, USA found levels of corticosterone being consistently low in rapidly decapitated mice without anesthesia³².  

In India, legislation against cattle slaughter is in place throughout most states of India apart from Kerala, West Bengal, and parts of the North-East. Officially, stunning is a mandatory prerequisite for animal slaughterhouses in our country (Rule 6 of 2001 Slaughterhouse Act) and no animal can be slaughtered in front of other animals to avoid any further stress quotient. Stunning is also compulsory as per part 4(a) subclause of rule 4.1 of Food Safety and Standard Regulations, 2011³³.  

However, in reality, the situation is quite different. According to a PETA (People for the Ethical Treatment of Animals) report published last year, the slaughterhouses in India have been accused of cruelty against animals; the slaughterhouse workers slit animals’ throats with dull blades and let them bleed to death. Cattle are skinned and dismembered while they’re still alive and in full view of other animals³⁴. The West Bengal Animal Slaughter Act, 1950 allows some exemption in ritual slaughter provisions which according to the Supreme Court of India is illegal^4,2.

In 2017, the Supreme Court of India ordered state governments to stop the illegal slaughterhouses and set up enforcement committees to monitor the treatment of animals used for meat and leather³⁴. The Court also ruled that the Indian Constitution requires Indian citizens to show compassion to the animal kingdom, respect the fundamental rights of animals, and asked states to prevent cruelty to animals³⁵.  

Worldwide the situation is gradually changing towards enforcement of more stringent laws to stop the suffering of animals from ritual slaughters like halal and kosher. Halal without stunning is now banned in countries of European Union like Denmark, Netherland, Sweden, Switzerland, Luxembourg and very recently in Belgium^{36, 37, 38}. The argument of the Jews and Muslim religious authorities is that since stunning causes injuries to the animal’s brain, it cannot be considered ‘appropriate’ (i.e. healthy) for ritual slaughter, an argument which is no longer accepted by some of the nations20. Since 2015, stunning before slaughter has been implemented in the United Kingdom, but their efforts have not yet been fully successful. While some international halal certifying authorities have agreed to this clause, most of them have not, which includes those in major halal meat importing countries like UAE, Malaysia, Singapore and Indonesia³⁹. Therefore, it is evident from the above discussion that for animal slaughter, based on the market, it is primarily the religious tradition which decides upon the fate of the animal and not any scientific attitude; and if that tradition is big enough to generate a trillion-dollar economy then animal welfare aspects are readily compromised.  

In the interest of animal wellbeing and preservation of animal rights, not religious or economy driven practices, but more scientific and humane approaches are desired.  

This is a translation of the article ‘Halal vs Jhatka: A Scientific Review’ written by Dr. Souvik Dey published at bangodesh.com.
References / Footnotes

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2. Euthanasia and slaughter of livestock. Temple Grandin. Journal American Veterinary Medical Association, 1994 Vol 204, pp 1354-136.

3. https://www.independent.co.uk/life-style/food-and-drink/what-is-halal-meat-the-big-questions-about-religious-slaughter-answered-9331519.html.

4. “Beefed up law”. The Telegraph.com. 18 January 2012. Retrieved 8 November 2013.

5. https://www.salaamgateway.com/en/story/SALAAM03102016111130/

6. Pozzi, P.; Geraisy, W.; Barakeh, S.; Azaran, M. Principles of Jewish and Islamic Slaughter with Respect to OIE (World Organization for Animal Health) Recommendations. Isr. J. Vet. Med. 2015, 70, 3.

7. Is a “Good Death” at the Time of Animal Slaughter an Essentially Contested Concept? ulAin Q, Whiting TL. Animals (Basel). 2017. Vol 7(12). pii: E99.

8. https://www.shechitauk.org/wp-content/uploads/2016/02/A_Guide_to_Shechita_2009__01.pdf

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13. The arteries of brain base in species of Bovini tribe. Zdun M, Frąckowiak H, Kiełtyka-Kurc A, Kowalczyk K, Nabzdyk M, Timm A. Anat Rec (Hoboken). 2013. Vol 296(11):1677-82.

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20. https://www.shechitauk.org/wp-content/uploads/2016/02/A_Guide_to_Shechita_2009__01.pdf

21. Euthanasia by decapitation: evidence that this technique produces prompt, painless unconsciousness in laboratory rodents. Holson RR. Neurotoxicol Teratol. 1992. Vol 14(4):253-7.

22. https://www.research.uci.edu/compliance/animalcare-use/research-policies-and-guidance/euthanasia.html

23. Analysis of Stress Indicators for Evaluation of Animal Welfare and Meat Quality in Traditional and Jewish Slaughtering. Bozzo G, Barrasso R, Marchetti P, Roma R, Samoilis G, Tantillo G, Ceci E. Animals (Basel). 2018. Vol 8(4). pii: E43.

24. Factors which affect blood variables of slaughtered cattle. Petty DB, Hattingh J, Ganhao MF, Bezuidenhout L. J S Afr Vet Assoc. 1994. Vol 65(2):41-5.

25. Determination of plasmatic cortisol for evaluation of animal welfare during slaughter. Ceci E, Marchetti P, Samoilis G, Sportelli S, Roma R, Barrasso R, Tantillo G, Bozzo G. Ital J Food Saf. 2017. Vol 6(3):6912.

26. Preslaughter stress and muscle energy largely determine pork quality at two commercial processing plants. Hambrecht E, Eissen JJ, Nooijent RI, Ducro BJ, Smits CH, den Hartog LA, Verstegen MW. J Anim Sci. 2004. Vol 82(5):1401-9.

27. The effect of stress on livestock and meat quality prior to and during slaughter. International Journal for the Study of Animal Problems, Grandin, T. 1980. Vol 1(5), 313-337.

28. Effect of lactic acid concentration on growth on meat of Gram-negative psychrotrophs from a meatworks. Gill CO, Newton KG. Appl Environ Microbiol. 1982. Vol 43(2):284-8.

29. Molecular mechanisms of glucocorticoid action B. B. P. Gupta and K. Lalchhandama. Current Science. 2002. Vol. 83, No. 9 pp. 1103-1111.

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31. Impact of Adrenaline or Cortisol Injection on Meat Quality Development of Merino Hoggets. Dario G Pighin, Sebastian A Cunzolo Maria Zimerman Adriana A Pazos Ernesto Domingo Anibal J Pordomingo Gabriela Grigioni. Journal of Integrative Agriculture. Volume 12, Issue 11, November 2013, Pages 1931-1936.

32. Unaltered hormonal response to stress in a mouse model of fragile X syndrome. Qin M, Smith CB. 2008. Vol 33(6):883-9.

33. Guide to Animal Welfare Laws Target group – Law enforcement agencies. Animal Welfare Board of India Ministry of Environment Forests & Climate Change, Government of India.

34. PETA Calls on all States to Stop Illegal Slaughter of Animals as Per Supreme Court Order, Nikunj Sharma and Shambhavi Tiwari, PETA India (31 March 2017).

35. Supreme Court stays high court judgment on cow slaughter, The Times of India (Jan 24, 2017).

36. https://www.reuters.com/article/us-dutch-religion-slaughter/dutch-vote-to-ban-religious-slaughter-of-animals-idUSTRE75R4E420110628

37. http://theconversation.com/danish-halal-and-kosher-ban-leaves-religious-groups-with-nowhere-to-turn-23392

38. https://www.nytimes.com/2019/01/05/world/europe/belgium-ban-jewish-muslim-animal-slaughter.html

39. The stunning and slaughter of cattle within the EU: A review of the current situation with regard to the halal market. Fuseini, A., Knowles, T. G., Lines, J., Hadley, P. J., & Wotton, S. B. Animal Welfare, 2016. Vol 25(3), 365-376.