Necrotic rhinitis is an uncommon, sporadic disease of young pigs characterized by suppuration and necrosis of the snout, arising from wounds of the oral or nasal mucosa. Confusion exists in the literature because of the use of the misnomer “bullnose” to also describe atrophic rhinitis Atrophic Rhinitis in Pigs Atrophic rhinitis is caused by infection with toxigenic Pasteurella multocida. Signs include coughing, sneezing, and in severe cases, nasal bleeding and poor growth. Diagnosis is based on clinical... read more .
Fusobacterium necrophorum is commonly isolated from the lesion and undoubtedly contributes to necrotic rhinitis, but other types of organisms are frequently present. They gain entry through damage to the roof of the mouth, often as a result of clipping the needle teeth too short or using blunt clippers.
Signs of necrotic rhinitis include:
Generally, only one or two pigs in a herd are affected.
The facial swelling usually is hard, but incision reveals a mass of pinkish gray, foul-smelling necrotic tissue, or greenish gray tissue debris, depending on the age of the lesion. The nasal and facial bones become involved, and facial deformity may be marked.
Necrotic rhinitis is readily differentiated from atrophic rhinitis Atrophic Rhinitis in Pigs Atrophic rhinitis is caused by infection with toxigenic Pasteurella multocida. Signs include coughing, sneezing, and in severe cases, nasal bleeding and poor growth. Diagnosis is based on clinical... read more by the bulging type of facial distortion seen in the former. The character of the exudate and its location within the tissue of the snout or face are also distinctive of necrotic rhinitis.
Because teeth clipping is no longer routinely practiced, necrotic rhinitis has reduced in significance. Prevention is directed toward avoiding injuries to the mouth and snout, improving pig processing techniques, and improving sanitation. When the disease occurs repeatedly, needle teeth should be clipped carefully.
If necrotic rhinitis is advanced, treatment may not be advisable. Early surgical intervention and packing the cavity with sulfonamide or tincture of iodine may be useful. In young pigs, sulfamethazine given PO is of value.