What potential change can occur if dairy cows are fed lower-quality feed?

Feeding dairy cows lower-quality feed can significantly impact the quality of milk produced, making the choice of decreased quality of milk produced the correct answer. The nutritional composition of the feed directly affects the milk’s nutrient profile, including its fat content, protein levels, and overall quality. Lower-quality feed may lack essential nutrients and may not provide adequate energy, leading to diminished overall health and productivity in the dairy cows.

As a result, the milk produced may contain reduced levels of fat and protein, adversely affecting its quality. This change can also influence the milk's flavor, shelf life, and processing characteristics—factors that are crucial for consumers and manufacturers alike. Therefore, using higher-quality feed is essential to optimize the dairy cows’ health and the milk’s overall quality.