Final answer:
The two environmental mastitis pathogen groups include contagious pathogens like Staphylococcus aureus and environmental pathogens such as Escherichia coli and Klebsiella spp. These bacteria cause infections in the cow's udder, with environmental pathogens typically found in dirty or wet conditions.
Step-by-step explanation:
The two environmental mastitis pathogen groups are generally classified based on the environment in which the bacterial pathogens are found and mode of transmission to the cow's udder. These include:
- Contagious pathogens, which are spread from cow to cow, often during the milking process. Common examples include Staphylococcus aureus and Streptococcus agalactiae.
- Environmental pathogens, which are present in the cow's environment and can cause infection, particularly between milking sessions. Significant examples include Escherichia coli Klebsiella spp. Streptococcus uberis, and Streptococcus dysgalactiae.
- Environmental pathogens are more likely to cause mastitis when cows are exposed to dirty or wet conditions that harbor these bacteria.