Infections with mit Clostridium perfringens
Enterotoxemia in calves is mainly caused by Clostridium perfringens Typ A and D, followed by Typ B and C. A sudden proliferation of Clostridia in the small intestine and the formation of toxins lead to diffuse haemorrhagic-necrotic enteritis.
Infections with E. coli
The most important types of E. coli are F5 (K99) und F41.
E. coli diarrhoea of the newborn calf is characterised by aqueous, yellowish faeces. It affects calves in the first two to three weeks of age. The causative agents are endotoxins in the small intestine.
Septicaemia by E. coli is not very common in newborn calves. Clinical signs are fever and poor general condition with high lethality.
Infections with Mannheimia haemolytica
Enzootic bronchopneumonia is one of the most important respiratory diseases. It is mainly caused by obligate pathogenic Mannheimia hemolytica, which induce an acute fibrinous-necrotic pneumonia. Also viruses and other bacteria such as Pasteurella multocida, Bordetella spp., Histophilus (Haemophilus) somnus and Mycoplasma spp. as well as stress (e.g. transport) contribute to the development of this disease.
Twelve different serotypes of Biovar A can be distinguished, whereas A1 and A6 are responsible for the disease in cattle (latent infection with different serotypes). Calves and young animals are affected primarily.
Infections with anaerobic bacteria
Infectious diseases such as dermatitis digitalis (Mortellaro) are determined by many factors. Anaerobic bacteria (e.g. Porphyromonas sp., Prevotella sp., Fusobacteria), poor animal environment and factors such as poor conditions of claws as well as immunosuppression are responsible for the infection. At an acute onset, 80 to 90 percent of the herd can be affected.
Vaccination with autogenous vaccines in cases of mastitis caused by Streptococci, Staphylococci, E. coli and coliform bacteria or Arcanobacterium pyogenes can decrease the somatic cell count, accelerate the healing and protect against infection.
Viral papillomatosis can be treated with autogenous vaccines.
Infections with Trichophyton verrucosum are most common. Because dermatophytes are slow growing organisms, the production of inactivated, autogenous vaccines against dermatopyhtes takes four to six weeks. Booster vaccination for several years is indicated as the spores can survive for such a long period and cause new infections.