In Japan, a country of restrained meat consumption, by far the most expensive domestically produced meat is beef that comes from the crosses of traditional black-coated, small-stature breeds of wagyū (Japanese cattle used for centuries as draft animals) and European animals. Kōbe beef from Hyōgo prefecture is produced by feeding penned heifers for up to three years, regularly massaging them and giving them beer to drink during the summer, and it is so highly marbled that it contains 20–25% of fat compared to 6–8% for the USDA prime beef.
The most expensive cuts look more white than red and are sold for more than $500/kg. And the even more expensive Matsuzaka beef (from Mie prefecture) has an extremely high fat/meat ratio; the animals are also fed beer in summer but are also massaged with shōchū (Japanese liquor).
Dietary recommendations by FAO/WHO experts set the acceptable range of total fat intake at 20–35% of all food energy, with minima at 15% in order to ensure not only adequate total energy intake but also the supply of essential fatty acids and bioavailability of fat-soluble vitamins A, D, E and K
Modern dietary research has convincingly established that it is desirable to limit the intake of SFA and replace it by MUFA (in practice, this means by consuming more oleic or erucic acid, that is, olive and rapeseed oil) and PUFA (present in fish). Dietary recommendations for adults are to limit SFA to 10% of all energy intakes while consuming at least 6% and up to 11% of all energy as PUFA, especially as n-6 PUFA and n-3 PUFA
While many fatty acids are easily substituted by other structurally similar compounds, there are two essential fatty acids that must be present in all healthy diets: linoleic acid (a primary ω-6 PUFA) and α-linolenic acid (an ω-3 PUFA) must be digested completely preformed in order to become precursors of prostaglandins (that act as regulators of gastric function, smooth-muscle activity and hormonal release) and parts of cell membranes. Inadequate supply of these acids is manifested in scaly rash, dermatitis, neural abnormalities and reduced growth. US guidelines for linoleic acid recommend average per capita intakes of 17 g/day for adult men and 12 g/day for adult women, while the rates for α-linolenic acid are set at, respectively, 1.6 and 1.1 g/day. Red meat, with between 0.3 (beef) and 0.4 g (mutton) of ω-6 fatty acids per 100 g of edible portion, is as good or a better source of these nutrients as oily fish, but ω-3 acids are far more abundant in oily fish (more than 2 g/100 g compared to just 0.1–0.2 g/100 g).
Despite many specific uncertainties, the cumulative epidemiological evidence is thus fairly conclusive, both in cases of CVD and cancer links to meat consumption: moderate meat intakes are the optimal choice to counsel, particularly when considering the benefits of ingesting complete proteins and easily absorbable micronutrients. Given a diverse diet, moderate food energy intake may be a much more important determinant of health and longevity than a particular dietary composition; this benefit is due to a positive effect of caloric (or dietary) restriction
Nearly 100,000 deaths due to hospital-acquired bacterial infections (Peleg and Hooper 2010).
Nearly half of all meat sold in US supermarkets is contaminated with Staphylococcus aureus, whose specific genotypes in different meats point to its origin in the animals rather than in the human handlers (Waters 2011).
This species is now infamous for its high degree of antibiotic resistance (96% of samples in studied meats were resistant, more than half of them to at least three different drugs), and its methicillin-resistant strains (MRSA) pose a greater danger to hospitalized patients than their illnesses or operations because that drug has been, in many cases, the last effective treatment. Until recently, MRSA findings in animals were limited to dairy cattle with mastitis, but since 2005 a bacterial clone (CC398, whose origin remains unknown) has been colonizing pigs, calves, dairy cows and broilers (Vanderhaeghen et al. 2010). Obviously, a possibility of this clone, and other virulent microbes, spreading to humans is a major concern. Animal-to-human spread of antibiotic resistance can take place by direct contact with animals as well as through the food chain, and Marshall and Levy (2011) summarize well-documented cases of such transmissions. Modeling suggests that the appearance of antibiotic-resistant commensal bacteria in humans has the greatest impact in the earliest stage of emerging resistance (Smith 2002).
The three most fundamental factors behind the rising meat consumption have been the worldwide adoption of mechanical prime movers in agriculture, availability of inexpensive synthetic nitrogenous fertilizers, and new varieties of crops that doubled, even tripled, traditional yields and released more farmland previously used to produce food crops for growing high-quality feed crops.
Other technical advances that promoted higher consumption of meat have included refrigeration and the combination of efficient diesel engines and large ships that ushered in the era of inexpensive seaborne trade. Large-scale commercial refrigeration allowed for unprecedented economies of scale in slaughtering and distribution, while household refrigerators (and also freezers) made meat purchasing and cooking more convenient, less wasteful and less expensive. Emergence of intercontinental meat trade, first as chilled meat, later also as massive shipments of live animals, has been another important factor in making meat consumption more affordable.
Since the 1950s, most countries – with notable exceptions of those engaged in protracted civil wars (Sudan being the worst example) or ruled by regimes willing to starve their own people (such as North Korea with its recurrent famines) – have seen significant economic advances that were accompanied by gains in average quality of life and often by impressive improvements of food supply. Another notable exception has been India, a nation with major culturally dictated restrictions on meat eating that has also struggled with providing enough food for its expanding population: it has done so only by maintaining an overwhelmingly vegetarian diet, with average annual meat supply remaining at only little more than 3 kg/capita.
A female hog is ready to reproduce about 32 weeks after her birth, and gestation lasts about 16 weeks (114 days) after mating or artificial insemination. Sows farrow (give birth) to litters of 7–12 (average 9) piglets, each weighing about 1.5 kg. Piglets are nursed for two to three weeks, and sows can be ready to reproduce shortly after weaning and hence they average slightly more than two litters a year. Those are natural constants, but breeding for meat growth and feeding in confinement have greatly shortened the post-weaning growth. In wild, the normally active pigs – foraging (rooting) in herds and covering considerable distances every day – reach full adult weight only after 2 years for females and 3 years for males and can live for as long as 8–15 years. Pigs grown in semi-confined conditions and fed ad libitum obviously mature faster (in less than a year) and those reared in severely confined conditions and fed optimal diets can reach their slaughter weight of 110–120 kg in as little as 22 weeks after their birth but 24 weeks, or about 5.5 months, is a more common span.
Cattle cycle is naturally the longest of the three dominant species of meat animals, and its greatest change came only during the post-weaning stage. Heifers (young females before their first pregnancy) reach sexual maturity 15 months after birth but are mated or artificially inseminated to have their first calf at the age of 2 years. Their gestation period lasts nine months, twin calves are a rarity, calves stay with cows (even in the US the pairs are maintained on pasture with minimal or no grain feeding) six to eight months and their diet may be supplemented by grass. After weaning, most male calves are castrated (these steers are then fed to reach market weight), and only a small share of all males is kept to become breeding bulls. Cows are re-bred 2–3 months after their birth resulting in a 12-month calving interval, and they stay productive in a breeding herd for at least 7 years.
Heifers and steers could be left on pasture, and it could then take at least two but as much as four, even five, years before they reach their slaughter weight. But the most common US practice is to put the weaned animals on grass or to feed them other roughage for 6–10 months until these stockers reach at least 270 kg (and as much as 360 kg), and they are then moved to feedlots where they are fed grain-based rations supplemented by a minimum of roughage required by ruminants. After five months of intensive feeding, they reach their market weight in excess of 500 kg. Consequently, the standard US sequence from the birth of a female to the slaughter of its offspring (heifer or steer) that has gone through stocker and feeder stages is at least 50 and up to 56 weeks compared to at least 145 weeks for animals raised solely by grazing.
In 2010, the global slaughter of large mammals killed for meat surpassed 300 million heads of cattle and water buffaloes; it approached 1.4 billion pigs and 1 billion for sheep and goats, and nearly 5 million horses and more than 2 million camels were also killed. Numbers for poultry are less accurate, but the best totals are about 55 billion chicken and more than 3 billion ducks and turkeys.
Killing without stunning remains the norm in ritual Muslim (zabiha) and Jewish (shechita) slaughter required to produce halal or kosher meat, but in modern mass slaughtering of meat animals, stunning, a procedure to cause immediate loss of consciousness, always precedes killing.
Stunning must induce unconsciousness that lasts long enough to prevent any potential recovery before an animal is killed, and it is done in three different ways: mechanically, by a captive bolt shot from a pistol placed at appropriate sites on the forehead of cattle, horses and pigs, and top of the head of sheep and goats; by electric current (requiring low-voltage AC with minima of 1.5 A for cattle, 1.25 A for pigs and 120 mA for broilers and layers and inducing epileptic state in the brain); or (since the early 1950s) by exposure to gases (very high levels of CO2 or inert gas mixtures, Ar or N2, for pigs, and mixtures of CO2, N2 and O2 for poultry).
Electric stunning is commonly applied to pigs, sheep and poultry. For mammals, the current is applied by two electrodes using tongs firmly emplaced on either side of their heads or under the jaw and on the neck behind their ears: because this head-only stunning is reversible, animals must be bled immediately before regaining consciousness. Electric stunning of birds is done most commonly by hanging them by their feet and passing their heads through electrified water bath.
Mechanical and electric stunning induce unconsciousness within less than 2 ms, that is, in time far shorter than is considered, from the sensory perspective, as instant (less than 300 ms). In contrast, gas stunning/killing (using inert gases or CO2) is not unsuitable for large animals, and the onset of anoxia is obviously accompanied by respiratory distress. Killing after stunning is done by severing jugular veins and carotid arteries and ensuing bleeding (exsanguination) that causes cerebral anoxia: constantly sharpened knives and practiced skills are all that is needed at that point.
Dead cattle first has its head removed, hide stripped, shanks removed at knees and hocks, the tail cut off, the carcass split and all internal organs taken out (some post-bleeding operations may take place in a different order). Killed pigs are bled, scalded and de-haired by scarping; head, leaf fat and viscera are removed but shanks and skin are left on. Broilers are gathered (usually by hand) from the growing-out houses, put into boxes and driven to nearby processing plants. There they are hung by feet on conveyor belts and stunned in vats of electrified salt water, and neck cutters then sever their carotid arteries. Birds are then bled, scalded and mechanically de-feathered, heads and feet are cut off, carcasses are manually eviscerated, inspected, washed, chilled, packed and labeled, and all the time their internal temperature should be less than 4.4°C in order to minimize the risk of Salmonella infestation (USDA 1999).
Muscles of large animals become meat only after their glycogen is decomposed to lactic acid and the muscle pH falls from neutral at slaughter to 5.8–5.4 a day later. This lower pH imparts typical meat taste and flavor, and it also helps to extend storage life by retarding growth of bacteria.
The French term charcuterie (cooked flesh) is traditionally restricted to processed pork-based products (bacon, ham, sausages, terrines, pates, confits), while Italian salumi and German Fleischwaren can contain meat from many species of mammals (including donkeys, wild boars or horses)
The commercial success of modern meat production and the worldwide diffusion of CAFOs is predicated on reliable and relatively inexpensive supply of mixed (compound) feeds that are assembled entirely from domestic inputs or from ingredients imported from several continents and that can include a remarkable variety of phytomass and, not uncommonly, also processed animal matter.
Modern feeds should result in rapid weight gains while maintaining animals in good health; that the latter goal has been in some cases superseded by the former quest should be a matter of serious concern.
An example of this poor treatment is to be chosen according to the quantity of suffering, then none rivals the way of raising billions of modern broilers. All of America’s leading broiler producers (Tyson, Pilgrim’s Pride, Perdue) follow only the voluntary guidelines of the National Chicken Council whose latest update, approved in January 2010 (NCC 2010), allows more space than the previous recommendations but still fails to meet acceptable conditions. Their first rule of management practices says that “Birds are allowed to roam freely throughout the growing area,” but half a dozen lines below that statement, it specifies a minimum of 1.3 ft2/bird in the rearing house, an area smaller than two sheets of letter (A4) paper, hardly a space suitable for free roaming.
The Dimness that prevails in broiler houses (0.5-ft candle or 5.38 lux) is merely an equivalent of a moonlit night or roughly just 1/100 of light delivered by a typical fluorescent light in modern kitchens. As distressing as living in high density in dimly lit spaces on an accumulated layer of excrement may be – the first condition prevents a normal range of activities, the second one destroys normal circadian rhythm, the last one damages feet and burns skin – that dismal combination has not been the worst part of the deliberate treatment of broilers: that dubious title belongs to the selection for excessive growth of their breast meat that induces suffering that is both grotesque and deadly (RSPCA 2002; Turner et al. 2005; AWI 2010). Rapid growth of breast muscle transfers the center of the bird’s gravity forward, impairs the bird’s already restricted movement and creates serious leg problems, and it also strains its cardiovascular system. Low price of broiler meat and its increasing affordability for poorer segments of modern society could be the only defenses of this reprehensible practice.
Europe has been ahead of the US in outlawing the most offensive practices. Matheny and Leahy (2007) made a detailed comparison of farm-animal legislation in the US and Europe where several common, and some national, standards allow more space and ban a number of practices that are still legal in US welfare (including gestation crates for sows and beak trimming of broilers). What is perhaps most unacceptable is that so much more could be done to limit the suffering of animals without any drastic increases in the cost of meat production: there is simply no acceptable excuse for claiming that the CAFO practices evolved during the last two generations represent optimum solutions to be followed, unchanged, in coming decades.
There is no doubt that human evolution has been linked to meat in many fundamental ways. Our digestive tract is not one of obligatory herbivores; our enzymes evolved to digest meat whose consumption aided higher encephalization and better physical growth. Cooperative hunting promoted the development of language and socialization; the evolution of Old World societies was, to a significant extent, based on domestication of animals; in traditional societies, meat eating, more than the consumption of any other category of foodstuffs, has led to fascinating preferences, bans and diverse foodways; and modern Western agricultures are obviously heavily meat-oriented. In nutritional terms, the links range from satiety afforded by eating fatty megaherbivores to meat as a prestige food throughout the millennia of preindustrial history to high-quality protein supplied by mass-scale production of red meat and poultry in affluent economies.
Meat is undoubtedly an environmentally expensive food. Large animals have inherently low efficiency of converting feed to muscle, and only modern broilers can be produced with less than two units of feed per unit of meat. This translates into relatively large demands for cropland (to grow concentrates and forages), water, fertilizers and other agrochemicals, and other major environmental impacts are created by gaseous emissions from livestock and its wastes; water pollution (above all nitrates) from fertilizers and manure is also a major factor in the intensifying human interference in the global nitrogen cycle.
But to say that “1 kg of fresh vegetables is environmentally preferable to 1 kg of meat” (Reijnders and Soret 2003) – a conclusion based on a Swiss study (Jungbluth 2000) according to which organic vegetables incurred 0.016 ecopoints/kg compared to 0.08 ecopoints/kg for meat – is a disingenuous comparison that may reinforce anti-meat bias but that completely leaves out the qualitative differences between the two categories of foodstuffs. Moreover, balanced nutrition, especially that of young children, cannot be achieved by eating only organic vegetables or only red meat, and merits of both of those food categories should be compared only within a broader dietary framework.
Many excesses that have come to characterize modern, intensive and mass-scale meat production – particularly those concerning inconsiderate treatment of animals, their stressful transportation and often callous slaughtering, as well as the narrow concentration on rapid weight gains obtained through confined feeding and a heavy use of antibiotics – should be criticized, and they should be eventually either banned or substantially modified. Similarly, the extent to which natural ecosystems (particularly tropical forests) have been (and are still being) converted to pastures as well as frequent overgrazing of grasslands and damage done by livestock to soils and the impact of atmospheric emissions and water pollution generated by livestock are matters of considerable concern that require appropriate modifications and improvements. And we should question the extent to which arable land is devoted to monocultures (mostly corn and soybeans) whose harvests are needed for animal feeding.
But the prevalence of these objectionable practices and the validity of these concerns are not convincing arguments against meat eating. Those practices are not inherent prerequisites of large-scale meat production; they are essentially malpractices committed as a part of a short-sighted quest for maximized meat output at minimized cost. Our understanding of livestock requirements, feed production and animal feeding, slaughtering and processing makes it possible to practice balanced and rational ways of meat production aimed at minimizing its environmental impacts and maximizing its health benefits.
Meat consumption is a part of our evolutionary heritage; meat production has been a major component of modern food systems; carnivory should remain, within limits, an important component of a civilization that finally must learn how to maintain the integrity of its only biosphere.
Studies show that prevalence of all forms of “vegetarianism” is no higher than 2–4% in any Western society and that long-term (at least a decade) or life-long adherence to solely plant-based diets is less than 1%, and that the single largest category are younger, more educated females living in households with higher incomes (Frank and White 1994; The Vegetarian Resource Group 2001). Many of them are “ideological” or “moral” vegans who chose the diet for its presumed superiority (often perceived in quasi-religious terms) rather than pragmatic vegetarians who switched to a meat-free diet as a means of improving their health after discovering that they have an elevated risk of cardiovascular disease (CVD) or cancer mortality (Ginter 2008).
And one of the largest groups among vegetarians consists of teenage females, and Worsley and Skrzypiec (1997) found that those who make the choice are more concerned about their appearance than their peers and report a greater frequency of extreme weight loss behaviors. This suggests a link between teenage vegetarianism and female adolescent identity rather than a fundamental concern about animal welfare or environmental impacts of eating meat
Very slow progress in developing in vitro meat is obviously attributable to the challenge of replicating the complexity of animal muscles and related tissues. Replicating a skeletal muscle with its connective, enervating and blood-supplying tissues is a forbidding challenge that becomes even greater with red meats that should contain at least a minimum of marbling, without which they would not have expected taste when roasted. Not surprisingly, that is why white chicken meat (essentially pure protein) has been taken up first as a relatively easier challenge. There are two basic approaches to in vitro meat production: cultivating muscle cells or producing complete muscles (Edelman et al. 2005; Datar and Betti 2010). The first, simpler technique would attach embryonic myoblasts or adult myosatellite cells either on a collagen meshwork scaffold or on collagen beads (because the carrier would have to be edible) suffused with culture medium in a bioreactor.
Diffusional limitations restrict the scaffold-based growth of myocytes to layers just 100–200 µm thick, and even then layering would produce tissue lacking the structure of muscle tissue, and the tissue could substitute only for ground boneless meat. Growth of a fully structured muscle tissue would have to rely on muscle explants in suitable culture media, a challenge made particularly difficult by the absence of blood circulation. With uncertainties about Hayflick limit (number of cell doublings), it is impossible to know how much meat a single cell could eventually produce. Even if these techniques became fairly effective on a small experimental scale, their scaling up is predicated on the availability of an affordable culture media, on the presence of requisite growth factors (produced primarily by liver) and on an eventual development of massive bioreactors (on the order of 1,000 m3 compared to bench assemblies with volumes of a few liters) to produce commercial amounts of cultured tissues.