Rational: Salmonella Enteritidis (S. Enteritidis) is a globally significant zoonotic foodborne pathogen which has led to large numbers of deaths in humans and caused economic losses in animal husbandry. S. Enteritidis invades host cells and survives within the cells, causing resistance to antibiotic treatment. Effective methods of elimination and eradication of intracellular S. Enteritidis are still very limited. Here we evaluated whether a new intracellular antibacterial strategy using iron oxide nanozymes (IONzymes) exerted highly antibacterial efficacy via its intrinsic peroxidase-like activity in vitro and in vivo.

Effects of commercial antimicrobials and the individual and combinational use of commercial prebiotics and probiotics in feed from d zero to 41 on the growth performance, small intestine size, jejunal morphology, and ileal resident bacteria population of broiler chickens were determined. A total of 1,040 one-day-old male Ross × Ross 708 broilers were randomly distributed to 80 floor pens (5 treatments, 16 replications per treatment, 13 chicks per pen). Five dietary treatments were employed: 1) a corn soybean-meal basal diet (served as a negative control diet, NC); 2) a basal diet supplemented with a commercial prebiotic product (Pre); 3) a basal diet supplemented with a probiotic product containing Bacillus subtilis spores (Pro); 4) a basal diet supplemented with both prebiotic and probiotic products (Pre + Pro); and 5) a basal diet supplemented with commercial antimicrobials (served as a positive control diet, PC). At d 14, Pre diets improved the relative level of Lactobacillus in ileal mucosa as compared to NC, Pro, or PC diets (P = 0.045) without improving broiler BW. Broilers fed PC diets exhibited the highest BW gain from d 15 to 27, the lowest duodenum, jejunum, and ileum relative weights as percentage of BW at d 27, and the highest breast weight at d 42 (P = 0.026, 0.035, 0.002, 0.025, and 0.035, respectively). Broilers fed Pro or Pre + Pro diets exhibited higher BW gain from d 28 to 41 (P = 0.005) and higher overall BW gain from d zero to 41 (P = 0.039) than those fed other diets. Dietary treatments did not affect jejunal morphology or ileal resident Escherichia coli level at any age. From our results, including spores of Bacillus subtilis in feed may stimulate growth at a later age and may facilitate broilers in reaching their target weight sooner. Therefore, probiotics are recommended as potential alternatives to antimicrobials in chicken diets, especially in grower and finisher feed.

Individual neurons within the suprachiasmatic nuclei (SCNs) are capable of functioning as autonomous clocks and generating circadian rhythms in the expression of genes that form the molecular clockworks. Limited information is available on how these molecular oscillations in individual clock cells are coordinated to provide for the ensemble rhythmicity that is normally observed from the entire SCN. Because calcium influx via voltage-dependent calcium channels (VDCCs) has been implicated in the regulation of gene expression and synchronization of rhythmicity across the population of SCN clock cells, we first examined the rat SCN and an immortalized line of SCN cells (SCN2.2) for expression and circadian regulation of different VDCC α1 subunits. The rat SCN and SCN2.2 cells exhibited mRNA expression for all major types of VDCC α1 subunits. Relative levels of VDCC expression in the rat SCN and SCN2.2 cells were greatest for L-type channels, moderate for P/Q- and T-type channels, and minimal for R- and N-type channels. Interestingly, both rat SCN and SCN2.2 cells showed rhythmic expression of P/Q- and T-type channels. VDCC involvement in the regulation of molecular rhythmicity in SCN2.2 cells was then examined using the nonselective antagonist, cadmium. The oscillatory patterns ofrPer2andrBmal1expression were abolished in cadmium-treated SCN2.2 cells without affecting cellular morphology and viability. These findings raise the possibility that the circadian regulation of VDCC activity may play an important role in maintaining rhythmic clock gene expression across an ensemble of SCN oscillators.

For poultry producers, chronic low-grade intestinal inflammation has a negative impact on productivity by impairing nutrient absorption and allocation of nutrients for growth. Understanding the triggers of chronic intestinal inflammation and developing a non-invasive measurement is crucial to managing gut health in poultry. In this study, we developed two novel models of low-grade chronic intestinal inflammation in broiler chickens: a chemical model using dextran sodium sulfate (DSS) and a dietary model using a high non-starch polysaccharide diet (NSP). Further, we evaluated the potential of several proteins as biomarkers of gut inflammation. For these experiments, the chemical induction of inflammation consisted of two 5-day cycles of oral gavage of either 0.25mg DSS/ml or 0.35mg DSS/ml; whereas the NSP diet (30% rice bran) was fed throughout the experiment. At four times (14, 22, 28 and 36-d post-hatch), necropsies were performed to collect intestinal samples for histology, and feces and serum for biomarkers quantification. Neither DSS nor NSP treatments affected feed intake or livability. NSP-fed birds exhibited intestinal inflammation through 14-d, which stabilized by 36-d. On the other hand, the cyclic DSS-treatment produced inflammation throughout the entire experimental period. Histological examination of the intestine revealed that the inflammation induced by both models exhibited similar spatial and temporal patterns with the duodenum and jejunum affected early (at 14-d) whereas the ileum was compromised by 28-d. Calprotectin (CALP) was the only serum protein found to be increased due to inflammation. However, fecal CALP and Lipocalin-2 (LCN-2) concentrations were significantly greater in the induced inflammation groups at 28-d. This experiment demonstrated for the first time, two in vivo models of chronic gut inflammation in chickens, a DSS and a nutritional NSP protocols. Based on these models we observed that intestinal inflammation begins in the upper segments of small intestine and moved to the lower region over time. In the searching for a fecal biomarker for intestinal inflammation, LCN-2 showed promising results. More importantly, calprotectin has a great potential as a novel biomarker for poultry measured both in serum and feces.

Inflammation is the reaction of the immune system to an injury; it is aimed at the recovery and repair of damaged tissue. The inflammatory response can be beneficial to the animal since it will reestablish tissue homeostasis if well regulated. However, if it is not controlled, inflammation might lead to a chronic response with a subsequent loss of tissue function. The intestine is constantly exposed to a number of environmental triggers that stimulate inflammation and lead to a reduction in performance. The diet and dietary components constitute consistent inflammatory triggers in poultry. Dietary components, such as anti-nutritional compounds, oxidized lipids, mycotoxins, and excess of soluble fiber or protein, are all capable of inducing a low-grade inflammatory response in the intestine of broilers throughout a 5-week grow-out period. We hypothesized that dietary factor-induced chronic intestinal inflammation is a key driver of the lower performance and higher incidence of intestinal problems observed in poultry production. Therefore, this review was aimed at exploring feed-induced chronic inflammation in poultry, the constituents of the diet that might act as inflammatory triggers and the possible effects of chronic intestinal inflammation on the poultry industry.