What type of bacteria is associated with Campylobacter fetus in sheep?

Campylobacter fetus is a type of bacteria that is classified as a Gram-negative rod. This classification is based on its structure and staining characteristics, which are determined by the presence of a thin peptidoglycan layer surrounded by an outer membrane. Campylobacter species are typically curved or spiral-shaped, which can also align with the characteristics of spirilla; however, they are predominantly recognized as Gram-negative rods in bacteriological terms.

The relevance of recognizing Campylobacter fetus as a Gram-negative rod is critical when diagnosing infections in sheep, as it helps inform the proper treatment approaches and preventive measures. In particular, this bacterium is known to cause reproductive issues, such as abortions, in sheep, making the understanding of its classification essential for veterinarians working with livestock.

Other types of bacteria, such as Gram-positive cocci, filamentous bacteria, and those that are purely categorized as spirilla, do not accurately represent the characteristics of Campylobacter fetus, which is why they are not the correct responses in this context.