In a male, 11 months old, cross breed calf carcass reddish lesions were observed in the serous surfaces of different abdominal viscera. Some lymph nodes were also reactive.

These lesions correspond to a fibrous or fibro-adhesive peritonitis. This is clearly a chronic lesion. Probably a result of an old fibrinous peritonitis. It may be the sequel to poliserositis due to a systemic neonatal bacteremia (colibacillosis or streptococcus) or infection of the umbilical cord (the lesions in these cases are more severe on the ventral part).

These lesions may also occur as a result of viscera perforation such as the abomasum, the intestines, the reticle (traumatic reticuloperitonitis) or the uterus. Chronic peritonitis can also present with abdominal exudate and presence of suppurative abscessing lesions.

Plaques of fibrous material attached to the peritoneal serous membrane.

Plaques of fibrous material attached to the peritoneal serous membrane.

The spleen's serous membrane was also involved with multiple punctate reddish lesions.

The spleen’s serous membrane was also involved with multiple punctate reddish lesions.

The mesentery also had deposits of fibrous material of reddish-pink coloration.

The mesentery also had deposits of fibrous material of reddish-pink coloration.