How long how human agriculture (for animals) been a problem?

Intensive animal farming or industrial livestock production, also known as factory farming, is a production approach towards farm animals in order to maximize production output, while minimizing production costs.[1] Intensive farming refers to animal husbandry, the keeping of livestock such as cattle, poultry, and fish at higher stocking densities than is usually the case with other forms of animal agriculture—a practice typical in industrial farming by agribusinesses.[2][3][4][5][6] The main products of this industry are meat, milk and eggs for human consumption.[7] There are issues regarding whether factory farming is sustainable or ethical.[8]

Confinement at high stocking density is one part of a systematic effort to produce the highest output at the lowest cost by relying on economies of scale, modern machinery, biotechnology, and global trade. There are differences in the way factory farming techniques are practiced around the world. There is a continuing debate over the benefits, risks and ethical questions of factory farming. The issues include the efficiency of food production; animal welfare; and the environmental impact (e.g. agricultural pollution) and health risks.[9][10][11]