Various types of dietary fats undergo distinct fermentation processes by gut microbes, potentially leading to the production of neurotransmitters that can influence the gut. Serotonin and dopamine are recognized neurotransmitters with positive effects on gut function. A broiler chicken trial was conducted to evaluate the influence of dietary fat types on protein expression of 2 neurotransmitter transporters, dopamine (DAT) and serotonin (5-HTT). A total of 560 day-old (Ross 708) male broiler chicks were randomly assigned to 7 dietary treatments. The experimental treatments included a basal diet of corn-soybean meal (SBM), supplemented with 3% of various fats: poultry fat (CON), olive oil (OLIV), fish oil (FISH), canola oil (CANO), lard (LARD), coconut oil (COCO), or flaxseed oil (FLAX). Bodyweight (BW) and feed conversion ratio (FCR) were recorded. Ileal tissues were aseptically collected to determine the expression levels of DAT and 5-HTT through western blot analysis. In addition, plasma samples were analyzed for reactive oxygen metabolites (d-ROM) tests on d 55. Results showed that dietary fat type inclusion did not have any detrimental effect on growth performance parameters. The expression levels of DAT were higher (P < 0.05) in FLAX treatments compared to CON treatments on d 20 and d 55, respectively. Similarly, with 5-HTT levels, FLAX, CANO, and LARD treatments were higher (P < 0.05) than CON treatments on d 20 and d 55. However, higher levels of oxidative stress (d-ROM values) were recorded in COCO (32.75 Carr U), CANO (29 Carr U), and CON treatments (25.5 Carr U) compared to FLAX (18.5 Carr U; P < 0.05) treatment. These findings suggest that incorporating dietary flaxseed oil at a 3% level in the diet has significant potential to elevate the expression levels of intestinal DAT and 5-HTT without inducing oxidative stress.

The restriction on the use of antibiotics in poultry has led to an increase in the use of natural products that could serve as alternatives to antibiotics. Mushrooms contain bioactive compounds that exhibit antifungal, antiparasitic, antibacterial, antioxidant, antiviral, anti-inflammatory, and cytotoxic properties. Hence, they are being tested, revealing as performance-enhancing natural feed additives for livestock. This review focused on the role of different species of mushrooms commonly used in poultry on the performance, immunomodulatory actions, cholesterolemic properties, and meat quality of poultry birds. Different studies reviewed show that mushrooms could positively impact poultry production, improve growth performance, modulate immune response, exert tissue antioxidant activity, influence intestinal morphology, enhance gut microbiome, and improve lipid profile. The variations in their efficacy could be attributed to the variations in physicochemical properties of different species and dosage levels applied in the experiments. However, the use of mushrooms as a natural product supplement is in its infancy, and more basic, pilot and large-scale research is required to make it a viable approach for improving immune responses in the poultry industry.

This study evaluated the effects of varying levels of dietary green tea extract (GTE) on growth performance, Clostridium perfringens (CP) colonization, and inflammatory responses in broiler chickens during experimental subclinical necrotic enteritis (SNE). In a 21-day experiment, 480 one-day-old male broiler (Ross 708) chicks were equally allotted into four dietary treatment groups. From days 1 to 10, all groups received a corn–soy basal diet, switching to a wheat-fish diet on day 11. Treatments included CON (no GTE), GTX, GTY, and GTZ (250, 500, and 1000 mg/kg GTE, respectively). On day 11, each group split into ACON, AGTX, AGTY, and AGTZ, totaling eight treatments. From days 17 to 20, ACON, AGTX, AGTY, and AGTZ chicks were orally challenged twice daily with 3 mL CP26 (2.5 × 10⁸ CFU/mL). On d 16 (pre-challenge) and d 1 post-challenge, ileo-jejunal contents were collected for CP enumeration, and jejunum tissue was analyzed via qRT-PCR to determine the expression levels of IL-1β, IFNγ, TNF-α, TGFβ, IL-10, and MUC2 genes. Challenged chicks showed poorer (p ≤ 0.05) growth and higher intestinal CP, with a potential improvement in GTE-supplemented diets. Findings suggests that dietary GTE supplementation mitigated the characteristic growth depression during SNE, reduced intestinal CP infection, and modulated inflammatory response in broiler chicks.

Salmonella infection severely impacts poultry health, productivity, and food safety. Spray dried plasma (SDP) shows good efficacy as an alternative to in-feed antibiotics for broiler chickens. Our objective was to identify potential mechanisms of SDP benefits by analyzing effects on spleen proteome and in response to Salmonella Enteritidis challenge (SE). A 2 × 2 factor study of broilers (n = 240) were assigned to CON (control) or SDP (30g/kg) diet at 1 day of age, and gavaged with sterile tryptic soy or 7.46 × 10⁸ CFU SE /mL, resulting in 4 groups CON (n = 60), SDP (n = 60), CON-SE (n = 60) and SDP-SE (n = 60). On d 2 and d 5 post-challenge, chicks (n = 4/treatment) were euthanized, and spleen collected to isolate proteins, and measure using label-free liquid chromatography tandem mass spectrometry. Data were mapped to Gallus gallus Uniprot database, and differentially abundant proteins (DAP; P < 0.05) identified using ANOVA. Across all samples, 4,300 proteins were identified, and SDP treatment resulted 116 DAP. Proteins (56) that decreased were associated with positive regulation of I-kappaß kinase/NF- kappaß signaling and positive regulation of apoptosis process. Proteins that increased (60) were associated with integral components of endoplasmic reticulum membrane and necroptosis pathway. Analysis of the interaction between SDP and SE challenge found 119 DAP. The proteins that increased (87) were associated with RNA binding, ATP binding, mRNA splicing, and protein phosphorylation. Proteomic signatures of spleen reveals that the actions of SDP in broiler chicks are anti-inflammatory and anti-apoptotic and predicted to inhibit pro-inflammatory response through the inhibition of NF-ĸB. However, in the presence of Salmonella infection, it promotes regulated inflammatory response.

Bacitracin Methylene Disalicylate (BMD), as a feed additive to poultry diets, enhances digestion, prevents Salmonella enteritidis (SE) colonization, and treats current infections. The objective of this study was to utilize a quantitative proteomic approach to determine the effect of BMD feed additive on broiler chickens challenged with SE in the spleen proteome. At 1 d of age, chicks were randomly allocated into four groups: control with and without SE challenge (CON, n = 60; CON-SE, n = 60), BMD with and without SE challenge (BMD, n = 60; BMD-SE, n = 60). Birds in the CON-SE and BMD-SE treatment were administered SE inoculum by oral gavage. On day three and day seven post-gavage, the spleen was collected aseptically from birds in each treatment group (CON, n = 4/day; CON-SE, n = 4/day; BMD, n = 4/day; BMD-SE, n = 4/day). Proteomic analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed an increased abundance of 115 proteins and decreased of 77 due to the BMD. Proteins that decreased in abundance were enriched for fibrinogen complex and extracellular space, whereas proteins that increased in abundance were enriched for proteasome-mediated ubiquitin-dependent protein catabolic process and mitochondrion. Analysis of the interaction between BMD and the Salmonella challenge found 230 differentially abundant proteins including proteins associated with RNA binding, spliceosome, protein transport, and cell adhesion among the upregulated proteins, and those associated with protein folding, carbon metabolism, biosynthesis of nucleotide sugars, response to oxidative stress, positive regulation of NIK/NF-kappaB signaling, and inflammatory response among the downregulated proteins. The impact of BMD treatment on spleen proteome indicates an anti-apoptotic effect. BMD also modified the response of the spleen to the SE challenge with a marked decrease in proteins that prompt cytokine synthesis and an increase in proteins involved in the selective removal of unfolded proteins.