Weaning is a challenging stage of pig farming. Animals undergo environmental, social and dietary changes leading to weaning stress syndrome. In order to compensate for the detrimental effects of weaning stress, antibiotics and natural extracts are used as feed additives, sometimes without fully understanding the interactions between them or even with low concentrations of mycotoxins that are frequently present in feed. The aim of this study was to evaluate the effect of fosfomycin (FOS), Cynara scolymus extract (CSE), deoxynivalenol (DON) and their combined administration on intestinal health of weaned piglets. The experiment was designed as a 2 × 2 × 2 factorial arrangement with 3 factors (FOS, CSE and DON treatments), 2 levels each (presence and absence) and 3 repeats. Weaned piglets (n = 24) were randomly divided in groups to receive the different treatments, namely DON administered in diet (50 μg/kg BW), FOS administered into the drinking water (30 mg/kg BW), CSE administered in diet (15 mg/kg BW) and all their combinations. After 15 d, the animals were euthanized and gastrointestinal tract samples were immediately taken to evaluate gastrointestinal pH, Enterobacteriaceae to lactic acid bacteria (E:L) ratio, volatile fatty acid (VFA) concentrations, disaccharidase (lactase, sucrase and maltase) activity, histology (intestinal absorptive area [IAA] and goblet cells count) and mucus ability to adhere pathogenic Escherichia coli. From our results, FOS and CSE treatments, individually or combined, produced a lower E:L ratio, an enhanced production of butyrate, increased disaccharidase activity (particularly maltase), and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus. Deoxynivalenol did not show interactions with the other factors and its administration produced decreases on VFA, disaccharidase activity and goblet cells count. In conclusion, weaning piglets receiving diets containing FOS, CSE or both exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds. On the contrary, the presence of DON at sub-toxic concentrations produced detrimental effects on intestinal health. The knowledge of the physiological and pathological gut changes produced by these compounds contributes to understand their potential productive consequences.

Many of the beneficial effects on productive performance observed when vegetable extracts are incorporated as feed additives in intensive farming can be explained by an increase in bile production. An experiment was conducted to study choleretic and cholagogue effect of a Cynara scolymus extract formulation and of silymarin in pigs. Pigs were cannulated with a T-tube catheter in the bile duct. Bile production was continuously measured and re-infused to the duodenum through Oddi’s sphincter at the same production rate. Treatments: Group A (n = 6), commercial feed; Group B (n = 6), C. scolymus extract (300 g/tonne) and Group C (n = 6), silymarin (300 g/tonne). Bile production was recorded hourly for each animal during 24 h. Total bile acids’ concentrations in bile, just before and one hour after meals were evaluated. Average daily bile production for pigs in group B was 66% higher than for pigs in groups A or C (P < .05). When bile acids’ concentrations before and after meals were compared, only pigs from group B exhibited an increase (P = .0023). From this study, it was concluded that neither choleretic nor cholagogue effects are attained with silymarin supplementation. On the contrary, C. scolymus extract increases bile production and secretion in pigs.

Early weaning in intensive pig production induces stress, compromising gastrointestinal health. Poor fat digestion results from the piglets’ underdeveloped digestive system. Dietary emulsifiers can enhance fat utilization, and glyceryl polyethylene glycol ricinoleate (GPGR) has been shown to improve pig performance. This study evaluated GPGR’s effects on intestinal health in weaned piglets in a commercial production farm. A total of 380 just weaned (21 days old) piglets were divided in two groups of 190 animals each (in four replicates) that received either a basal diet (control) or a basal diet + 350 g/ton GPGR pharmaceutical formulation as top dress. Blood samples were collected at pre-established days, and intestinal sampling occurred 15 days post-weaning. Plasma cortisol, citrulline, intestinal morphology, mucus quality, enzymatic activity, volatile fatty acids (VFAs), and cecal microbiota were analyzed. GPGR did not alter plasma cortisol but increased citrullinemia (P: 0.024), suggesting greater enterocyte functional mass. GPGR piglets showed improved intestinal morphology (greater villus height, villus height:crypt depth ratio, and intestinal absorption area, p < 0.05) and higher enzymatic maltase activity (p ≤ 0.014). VFAs, bacterial adherence to mucus, and goblet cell counts were unaffected. Dietary GPGR increased Firmicutes and Actinobacteria (P: 0.014 and P: 0.045, respectively) while reducing Proteobacteria (p < 0.001). In conclusion, dietary GPGR promotes intestinal health in weaned piglets by improving epithelial structure, digestive function, and microbiota balance, representing a promising strategy to support piglets in overcoming the early nursery phase.

Fosfomycin (FOS) is an antibiotic used in pig farms for treatment and prevention of infections caused by resistant bacteria during the post-weaning period. Antibiotics and non-toxic concentrations of mycotoxins, such as deoxynivalenol (DON) are frequently found in the diet of animals. These compounds can establish interactions in the intestinal tract, which could affect and/or modify the penetration of FOS to enterocytes. The aim of this study was to determine the penetration of FOS into IPECJ-2 cells, a cell line derived from the small intestine of piglets, in the presence and absence of DON. The results from this study showed that there was statistically significant difference in the intracellular concentration of FOS between cells incubated with 580 µg/ml FOS and cells incubated with 580 µg/ml FOS and 1 µg/ml DON. The C_max of the intracellular antibiotic in the culture plates incubated with FOS in absence of DON was 45.81 µg/ml with a t_max of 4 h. When IPEC-2 cells were incubated with FOS and DON the C_max was 20.06 µg/ml and the t_max was 30 min. It is concluded that the non-toxic concentration of DON on IPEC-J2 cells after short-term exposure, interferes with the pharmacokinetics of the antibiotic.

Intestinal health of weaning piglets was studied after oral treatments with fosfomycin (FOS), Cynara scolymus extract (CSE), deoxynivalenol (DON) and their combinations. Piglets were divided in groups and received different treatments during 15 days, namely DON (1mg/kg of feed), FOS administered into the drinking water (30 mg/kg b.w.), CSE (300 g/ton of feed) and all possible combinations including a control group that received clean balanced diet. At day 15, three piglets from each group were euthanized and gastrointestinal tract samples were immediately taken to evaluate pH, bacteriology (enterobacteria and lactic acid bacteria), volatile fatty acids concentration (VFAs), disaccharidases activity (lactase, sucrase and maltase), histology (intestinal absorptive area [IAA] and goblet cells count) and adherence of bacteria to intestinal mucus. Animals receiving FOS and CSE treatments exhibited evident beneficial intestinal effects compared to animals receiving diets free from these compounds. This was revealed by a lower enterobacteria population together with a lower E/L, an enhanced production of butyric acid, an increased enzymatic activity (particularly maltase), and a greater IAA and goblet cells count along with an increase in pathogenic bacteria adherence to intestinal mucus. Interactions between both treatments resulted in similar beneficial effects as their individual administration. On the contrary, DON produced detrimental effects on intestinal health as a decrease was observed on volatile fatty acids production, enzymatic activity and goblet cells count in animals receiving diets containing sub- toxic concentrations of this mycotoxin. The knowledge of the intestinal effects of these compounds contributes to understand the physiological and pathological gut changes and their potential productive consequences.