Pathological Changes of the Rumen in Small Ruminants Associated with Indigestible Foreign Objects

The use of agriculture by-products is highly demanded for livestock nutrition. However, the employment of certain non-degradable materials could potentially induce concretions and lesions in ruminants’ forestomach. Thus, the aim of this study was to determine the morphological lesions showed in rumen containing indigestible foreign objects, named foreign bodies, in small ruminants. Twenty-two animals (12 goats and 10 ewes) presenting foreign bodies (2.750 ± 1.577 kg) were included in this study. Rumenotomies were performed to remove the foreign bodies, and rumen samples were taken for further morphological evaluations. Rumen samples from healthy small ruminants (n = 24) were also taken at slaughterhouses as controls. Morphologically, the rumen from affected animals showed a significant reduction of the ruminal papillae length (1.243 vs. 3.097), hyperplasia of the squamous epithelium, mononuclear infiltration in the subepithelial spaces and, less consistently, vacuolization of keratinocytes, presence of intraepithelial leukocytes and vascular changes of the lamina propria. It can be concluded that indigestible foreign bodies would cause ruminal lesions that would be able to trigger inflammatory and/or degenerative lesions. Our study demonstrates morphological lesions because of the presence of intraruminal foreign bodies, but further studies on the functional activity of the rumen in these cases are required. The avoidance of the presence of indigestible materials in agriculture exploitations is highly recommended in order to prevent the accumulation of indigestible foreign objects in small ruminants.