What are the causes fungle infections, signs,...

Factors that influence susceptibility of cows to fungl infection are: 
  
Age of the animal: Young animals are by far more susceptible to infection. This is probably related to lack of prior exposure/infection and thus no immunity. Adult cattle are also quite frequently affected. The overall incidence of ringworm based on evidence of hide damage in a number of European countries appears to be around 10% of cattle. 
  
Crowding together young animals 
  
Factors that decrease resistance to infection: Poor nutrition, concurrent disease, previous use of immunosuppressive drugs. 
  
Environmental factors may play a role, since the prevalence of the disease is increased in hot, humid climates. Calves kept indoors or exposed to foggy weather with little or no sunlight have an increased incidence.  

Symptoms:

• Skin lesions
• Pruritus
• Hair loss
• Poor growth 
  treatment :
• A member of the azole family
• Needs 2 or 3 weekly applications
• Kills the surface infection but not very sporicidal
• Applied as an emulsified wash
• Penetrates into hair follicles, but unable to do so if a lot of surface encrustation exists that prevents soaking of the deep follicles
•