When animals are slaughtered, meat can be contaminated with gut contents, faeces and urine, leading to bacterial infetion. In an attempt to counteract infection in their animals, farmers routinely inject them with doses of antibiotics. It's not unusual for their restaurant-workers to quit after just four or five weeks. The reasons are not had to find. They are at work in the evenings and at weekends, doing long shifts in hot, smelly, noisy environments.
Wages are low and chances of promotion minimal.
McDonald's have a policy of preventing unionisation by getting rid of pro-union workers. So far this has succeeded everywhere in the world except Sweden, and in Dublin after a long struggle. So there is no need to employ chefs or qualified staff - just anybody prepared to work for low wages. As there is no legally-enforced minimum wage in Britain, McDonald's can pay what they like, helping to depress wage levels in the catering trade still further. They say they are providing jobs for school-leavers and take them on regardless of sex or race.