Histamine in lambs with abomasal bloat, haemorrhage and ulcers.

The median concentration of histamine in abomasal fluid of lambs with abomasal haemorrhage and/or ulcers (group 2) was significantly (P < 0.05) higher than the concentrations in lambs presenting abomasal bloat (group 1) and in the healthy and the diseased controls. In group 2, there was also a strong correlation (R2 = 0.81) between the histamine concentrations in abomasal tissue and abomasal fluid, although the median value of histamine in the abomasal tissue was not statistically higher in this group than in the others. The urine of lambs in group 2 also had numerically higher median concentration of histamine than the other groups. Five out of eight tested strains of Lactobacillus spp. and one out of two strains of Clostridium sordellii, isolated from abomasal contents of lambs with abomasal disease, were strong producers of histamine. Bacterial production is one possible source for the increased histamine concentrations in lambs suffering from abomasal haemorrhage and/or ulcers.