Which of the following is a predisposing factor for Dermatophilus congolensis in cattle?

Dermatophilus congolensis is a bacterial pathogen responsible for dermatophilosis, also known as rain scald or mud fever, primarily affecting cattle. High humidity is a significant predisposing factor for infections caused by this bacterium. The organism thrives in conditions that are moist, as it requires water for the spores to germinate and for the bacteria to infect the host. In humid environments, the skin of cattle tends to stay moist, which facilitates the entry of the bacteria, leading to skin lesions and infections.

The factors that contribute to the development of dermatophilosis include exposure to wet conditions, which tends to be heightened in areas of high humidity. When the skin is compromised due to continuous moisture, it creates an ideal environment for the bacteria to multiply and invade, resulting in the characteristic skin lesions. This is why high humidity is directly linked to an increased risk of developing dermatophilosis.

In contrast, the other options, such as low temperature, high altitude, and dry conditions, do not create the necessary environmental conditions for Dermatophilus congolensis to thrive. Lower temperatures can inhibit the growth of many bacteria, high altitude is generally associated with drier air, and dry conditions do not support moisture retention on the skin,