Biomarkers for monitoring intestinal health in poultry : present status and future perspectives

Intestinal health is determined by host (immunity, mucosal barrier), nutritional, microbial and environmental factors. Deficiencies in intestinal health are associated with shifts in the composition of the intestinal microbiome (dysbiosis), leakage of the mucosal barrier and/or inflammation. Since the ban on growth promoting antimicrobials in animal feed, these dysbiosis-related problems have become a major issue, especially in intensive animal farming. The economical and animal welfare consequences are considerable. Consequently, there is a need for continuous monitoring of the intestinal health status, particularly in intensively reared animals, where the intestinal function is often pushed to the limit. In the current review, the recent advances in the field of intestinal health biomarkers, both in human and veterinary medicine are discussed, trying to identify present and future markers of intestinal health in poultry. The most promising new biomarkers will be stable molecules ending up in the feces and litter that can be quantified, preferably using rapid and simple pen-side tests. It is unlikely, however, that a single biomarker will be sufficient to follow up all aspects of intestinal health. Combinations of multiple biomarkers and/or metabarcoding, metagenomic, metatranscriptomic, metaproteomic and metabolomic approaches will be the way to go in the future. Candidate biomarkers currently are being investigated by many research groups, but the validation will be a major challenge, due to the complexity of intestinal health in the field

Host intestinal biomarker identification in a gut leakage model in broilers

International audienceAbstractIntestinal health problems are a major issue in the poultry industry. Quantifiable easy-to-measure biomarkers for intestinal health would be of great value to monitor subclinical intestinal entities that cause performance problems and to evaluate control methods for intestinal health. The aim of the study was to identify host protein biomarkers for intestinal inflammation and intestinal barrier damage. Proteomic analysis was conducted on ileal and colonic content samples of broilers under an experimental gut damage and inflammation model. Effects of the challenge treatment resulted in a worse gut condition based on macroscopic gut appearance (p < 0.0001). Also microscopic changes such as shortening of the villi and increased crypt depth (p < 0.0001) as well as higher infiltration of T-lymphocytes (p < 0.0001) were seen in the duodenal tissue of challenged animals. Several candidate proteins associated with inflammation, serum leakage and/or tissue damage were identified with an increased abundance in intestinal content of challenged animals (p < 0.05). Conversely, brush border enzymes were less abundant in intestinal content of challenged animals (p < 0.05). These candidate biomarkers have potential to be used in the field for detection of gut barrier failure in broilers

Applied research note : biomonitoring of mycotoxins in blood serum and feed to assess exposure of broiler chickens

Because European maximum guidance values of mycotoxins are only available for feed, mycotoxin exposure in animals is mainly monitored by feed analysis. However, proper sample collection is needed to ensure reliable results because of uneven distributions and disproportional spread of mycotoxins in feed which can hamper the evaluation of mycotoxin exposure in animals. A cross-sectional study was performed on 40 randomly selected broiler farms in Belgium. During a farm visit at the animal's age of 28 d, a pooled feed sample at the beginning and the end of the feed line was collected. Feed samples were analyzed by a validated multimycotoxin LC-MS/MS method. Moreover, serum samples were collected from 10 randomly selected chickens per farm. Serum concentrations of mycotoxins and major in vivo phase I metabolites were analyzed quantitatively, whereas the presence of phase II metabolites was determined in a qualitative approach by an UPLC-HRMS method. Deoxynivalenol (DON) was the most frequently occurring mycotoxin, being present in 74% of the feed samples, with an average concentration of 270 +/- 171 mu g/kg and a maximum concentration of 751 mu g/kg in positive samples. Also the acetylated forms 3and 15-acetyldeoxynivalenol (3 and 15ADON) were present in half of the samples, however, at lower concentrations (8 +/- 3 mu g 3ADON and 10 +/- 7 mu g 15ADON/kg). Only in 17.5% of the farms, DON was detected in serum samples at a mean serum concentration and standard deviation (SD) of 11 +/- 19 ng/mL. The maximum serum concentration of 49 ng DON/ mL was detected in broilers which were fed a diet that was contaminated with 191 mu g DON/kg, whereas the maximum concentration of DON in feed was 751 mu g/kg. Besides, 3 and 15ADON were only detected in 10% of the serum samples (max. 1.3 ng/mL). Sulfate conjugates of DON were only detected in a few serum samples. Qualitative screening for phase II metabolites of other mycotoxins showed similar results. Overall, correlations between feed and serum concentrations of all mycotoxins were lacking (R-2 = 0.18 for DON)

Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease

Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.