Limosilactobacillus reuteri and Lactiplantibacillus plantarum strains, previously isolated from weaned piglets, were considered for the evaluation of their adhesive characteristics. Lactobacilli were treated with LiCl in order to remove the surface protein layer, and probiotic activity was compared with those of untreated strains. The autoaggregation, co-aggregation to E. coli F18+, and adhesive abilities of LiCl-treated Limosilactobacillus reuteri and Lactiplantibacillus plantarum were significantly inhibited (p < 0.05) compared with the respective untreated strain. The hydrophobic and basic phenotypes were observed due to the strong affinity to chloroform and low adherence to ethyl acetate. In particular, L. plantarum showed higher hydrophobicity compared to L. reuteri, which may reflect their different colonizing ability. After treatment with LiCl to remove surface proteins, the adherence capabilities of L. reuteri and L. casei on IPEC-J2 cells decreased significantly (p < 0.001) and L. reuteri adhered more frequently. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) showed that both L. reuteri and L. plantarum had several bands ranging from 20 to 100 kDa. Two-dimensional gel electrophoresis showed an acidic profile of the surface-layer polypeptides for both bacterial strains, and more studies are needed to characterize their profile and functions. The results confirm the pivotal role of surface proteins in the probiotic potential of L. reuteri and L. plantarum.

The ever-increasing human population, the problem associated with climate change and recent crises—COVID-19 disease and trade conflicts—all impacted on the availability and cost of animal feed raw materials. This is clearly visible in realities which heavily rely on importation such as islands and small states, where producers involved in the agricultural sector were strongly affected by the sharp increase in prices. To deal with these global issues, alternative resources are perceived to replace conventional ingredients. This work aimed at assessing the nutritive value of different resources (sheep feed, mature carob, Maltese bread, wild asparagus, prickly lettuce, and loquat) for small ruminants present in the Maltese Islands, analyzing their chemical composition, gas production kinetics and antioxidant properties. In general, the variation in chemical composition resulted in different rumen fermentation kinetics (p < 0.007). The ratio between GP-24 h and GP-48 h was higher in Maltese bread than other substrates; loquat, prickly lettuce and wild asparagus showed lower fermentation kinetics in accordance with their high NDF and ADF contents. The antioxidant activity may be partially related to the polyphenolic content that was higher in wild asparagus, prickly lettuce and loquat. All feed characteristic confirmed their potential to be included as ingredients in ruminant diets and as a source of fiber.

The lactose-¹³C-ureide (L¹³CU) test, used in humans to measure oro-cecal transit time (OCTT) in breath CO₂, was assessed for its suitability in pigs as a noninvasive alternative to intestinal cannulation. The OCTT was determined with the L¹³CU test in breath and saliva samples when pigs were fed low or high dietary fiber (DF) (low fiber, 2.8% DF; high fiber 6.5% DF) diets, and 24 h after an i.m. injection with either lipopolysaccharide (LPS) or NaCl. The OCTT measured in breath was longer in LF-LPS than in LF-NaCl and HF-LPS groups (3.4 vs 2.9 h; p < 0.05). Additionally, LPS prolonged the OCTT of pigs, and DF prevented this effect. 90 % of OCTT estimates measured in saliva and breath CO₂ did not differ. We conclude that the L¹³CU breath test is useful for determining OCTT in pigs; saliva is generally suitable as a sample matrix for OCTT, but its use requires further validation.

The need for health-promoting foods that contain bioactive compounds has increased over the last few decades, largely due to the sharp rise of mortality in developed countries due to hypertension, cancer, diabetes, and obesity. Animal and plant-derived proteins have shown to be sources of beneficial peptides. The bioactive effect of food peptides occurs at the cellular level by modulating the different cell function as viability, growth and proliferation, DNA stability, apoptosis, and necrosis. This chapter describes the cytomodulatory effect of the major peptides from both animal and plant sources on different target cells. The concepts of digestibility, bioavailability, and bioaccesibility as prerequisites to determine the peptide bioactivity will also be discussed.