Assistant Laboratory Animal Technician (ALAT) Practice Exam

What chemicals are commonly added to animals' drinking water to reduce bacterial contamination?

1. Fluoride and iodine

2. Acid and chlorine

3. Chlorhexidine and alcohol

4. Hydrogen peroxide and potassium permanganate

The correct answer is: Acid and chlorine

The use of acid and chlorine in drinking water for animals is a common practice to help minimize bacterial contamination. Acidifiers, such as citric acid or phosphoric acid, can lower the pH of the water, creating an environment that is less favorable for bacterial growth. This is beneficial in preventing the proliferation of pathogens that could adversely affect the health of the animals. Chlorine is also widely used due to its properties as a disinfectant. When added to water, it effectively kills bacteria and other microorganisms. This combination of acidification and chlorination is particularly effective in maintaining the microbiological quality of drinking water in laboratory animal facilities. Other options, while they may serve certain purposes in particular scenarios, do not reflect the standard practice for reducing bacterial contamination in drinking water for animals. For instance, fluoride is primarily used for dental health rather than bacterial control, and chlorhexidine is not typically used in water. Alcohol, while a disinfectant, is not suited for use in water for animals due to its toxicity when ingested. Meanwhile, hydrogen peroxide and potassium permanganate are not common additives to animal drinking water for routine bacterial control.