[2] The 1865–1873 era provided five factors that expanded the industry to a national scale: In Milwaukee, Philip Armour, an ambitious entrepreneur from New York who made his fortune in Army contracts during the war, partnered with Jacob Plankinton to build a highly efficient stockyard that serviced the upper Midwest.

Perhaps the most energetic entrepreneur was Gustavus Franklin Swift, the Yankee who operated out of Boston and moved to Chicago in 1875, specializing in long distance refrigerated meat shipments to eastern cities.

[3] The Bureau of Corporations, predecessor of the Federal Trade Commission investigated the country's meatpackers for anti-competitive practices in the first decade of the 1900s.

The new laws helped the large packers, and hurt small operations that lacked economy of scale or quality controls.

When the Argentine industry finally secured a large slice of the British market, Pateros and trade restrictions limited its penetration of the Continent.

[8] Meat in China moved from a minor specialty commodity to a major factor in the food supply in the late 20th century thanks to the rapid emergence of a middle class with upscale tastes and plenty of money.

It was a transition from a country able to provide a small ration of meat for urban citizens only to the world's largest meat producer; it was a movement from a handful of processing facilities in major cities to thousands of modern meat-packing and processing plants throughout the country, alongside the rapid growth of a middle-class with spending money.

Meat-packing plants, like many industries in the early 20th century, overworked their employees, failed to maintain adequate safety measures, and actively fought unionization.

The isolated areas in which many plants are located put these workers at greater risk due to their limited ability to organize and seek redress for work-related injuries.

[13] NPR reports that pig and cattle slaughterhouse workers are nearly seven times more likely to suffer repetitive strain injuries than average.

[15] On average, one employee of Tyson Foods, the largest meat producer in America, is injured and amputates a finger or limb per month.

[17] In a 2018 study in the Italian Journal of Food Safety, slaughterhouse workers are instructed to wear ear protectors to protect their hearing from the constant screams of animals being killed.

[26] As authors from the PTSD Journal explain, "These employees are hired to kill animals, such as pigs and cows that are largely gentle creatures.

This emotional dissonance can lead to consequences such as domestic violence, social withdrawal, anxiety, drug and alcohol abuse, and PTSD".

[30] In a report by Oxfam America, slaughterhouse workers were observed not being allowed breaks, were often required to wear diapers, and were paid below minimum wage.

In the Covid-19 pandemic in 2020, this led to the paradoxical situation that mass slaughterhouses were infection drivers due to the bad labor conditions and at the same time suppliers of important therapeutics such as heparin, which subsequently became a scarce commodity.

[32] Medical historian Benjamin Prinz has therefore pointed to the fragility of today's healthcare systems, which themselves participate in environmentally destructive and disease-causing production chains.

[33] Contemporary concerns about the meat industry within the American context have often been colored by the COVID-19 Pandemic and the resulting supply chain issues.