An Immobilized Form of a Blend of Essential Oils Improves the Density of Beneficial Bacteria, in Addition to Suppressing Pathogens in the Gut and Also Improves the Performance of Chicken Breeding.

Antimicrobial growth promoters (AGP) are used in chicken production to suppress pathogens in the gut and improve performance, but such products tend to suppress beneficial bacteria while favoring the development and spread of antimicrobial resistance. A green alternative to AGP with the ability to suppress pathogens, but with an additional ability to spare beneficial gut bacteria and improve breeding performance is urgently required. We investigated the effect of supplementation of a blend of select essential oils (cinnamon oil, carvacrol, and thyme oil, henceforth referred to as EO; at two doses: 200 g/t and 400 g/t feed) exhibiting an ability to spare Lactobacillus while exhibiting strong E. coli inhibition ability under in vitro tests and immobilized in a sunflower oil and calcium alginate matrix, to broiler chickens and compared the effects with those of a probiotic yeast (Y), an AGP virginiamycin (V), and a negative control (C). qPCR analysis of metagenomic DNA from the gut content of experimental chickens indicated a significantly (p < 0.05) lower density of E. coli in the EO groups as compared to other groups. Amplicon sequence data of the gut microbiome indicated that all the additives had specific significant effects (DESeq2) on the gut microbiome, such as enrichment of uncultured Clostridia in the V and Y groups and uncultured Ruminococcaceae in the EO groups, as compared to the control. LEfSe analysis of the sequence data indicated a high abundance of beneficial bacteria Ruminococcaceae in the EO groups, Faecalibacterium in the Y group, and Blautia in the V group. Supplementation of the immobilized EO at the dose rate of 400 g/ton feed improved body weight gain (by 64 g/bird), feed efficiency (by 5 points), and cellular immunity (skin thickness response to phytoheamagglutinin lectin from Phaseolus vulgaris by 58%) significantly (p < 0.05), whereas neither yeast nor virginiamycin showed a significant effect on performance parameters. Expression of genes associated with gut barrier and immunity function such as CLAUDIN1, IL6, IFNG, TLR2A, and NOD1 were significantly higher in the EO groups. This study showed that the encapsulated EO mixture can improve the density of beneficial microbes in the gut significantly, with concomitant suppression of potential pathogens such as E.coli and improved performance and immunity, and hence, has a high potential to be used as an effective alternative to AGP in poultry.

Dietary supplementation of extracts of red sea weed (Kappaphycus alvarezii) improves growth, intestinal morphology, expression of intestinal genes and immune responses in broiler chickens.

BACKGROUND: Effects of supplementation of dried alkaline (referred to as MVP1) and aqueous (referred to as PBD1) extracts of Kappaphycus alvarezii, were evaluated in broiler (Vencobb 400) chickens (1-35 days post-hatch). In experiment I, each of the seven diets (basal diet with three levels (0.5, 1.5 or 5.0 g kg-1 diet) of MVP1 or PBD1 and a negative control was fed to 12 pen replicates containing five birds in each. In experiment II, each of three diets [a negative control, and PBD1 at two levels (1.0 or 1.5 g kg-1 diet)] was fed to 16 pen replicates of five chicks in each. RESULTS: Concentrations of total phenolics, phycobillins and free radical scavenging activity were higher (P < 0.01) whereas carrageenan was lower in PBD1 than in MVP1. In the experiment I, PBD1 at 1.5 g kg-1 diet improved (P < 0.05) body weight (BW) (7.11% higher). In the experiment II, both the treatments improved (P < 0.01) BW (9.18% and 8.47%, respectively) compared to the control. The group fed with PBD1@ 1.0 g kg-1 had higher (P < 0.05) haemagglutination inhibition titre, expression of intestinal claudin 2, TLR2A, NOD1, avian beta defensin 4, interleukin 2 and interleukin 6 genes than control. Treatments did not influence feed efficiency or levels of most of the antioxidant enzymes. Villus width and crypt depth were significantly higher in the group fed with 1.5 g kg-1 of PBD1. CONCLUSION: Supplementing dried aqueous extract of K. alvarezii at 1 g kg-1 diet may be an effective strategy to increase growth and immunity in broiler chickens. © 2020 Society of Chemical Industry.

Abatement of enteric methane production from lactating Murrah buffaloes (Bubalus bubalis) with improving production performance and immune status through dietary supplementation of composite feed additive.

Ruminant livestock production processes are the major sources of methane production in agriculture sector triggering global environmental pollution. Above 90% of world buffalo population present in Asian countries, India ranks first and contributes significantly to the environmental pollution by enteric methane emissions. In this study, we examined the effect of dietary composite feed additive supplementation on ruminal methane production, nutrient utilization, milk production and immune status of buffaloes (Bubalus bubalis). Eighteen lactating Murrah (Bubalus bubalis) buffaloes at early stage of lactation were divided into two groups of nine animals and fed a composite feed additive [consisted of (%, w/w) dried and ground leaves of Cordia dichotoma and Holoptelea integrifolia, 31.4 each; garlic oil, 0.6; sodium nitrate, 3.1; magnesium sulphate, 8.4; mustard oil, 12.6 and cottonseed oil, 12.5] which contained an ideal combinations of methane inhibitors, alternate hydrogen sinks and rumen stimulating agents to treatment (CFA) group animals along with basal feed of chaffed green sorghum (Sorghum bicolor) fodder, chaffed wheat straw and concentrate mixture for maintenance and milk production. The results showed a decrease (44.6%) in methane concentration in exhaled air of CFA group buffaloes with increase (p < 0.05) in digestibility of feed in comparison to control (CON). Total digestible nutrient (TDN) content of the ration fed to buffaloes of CFA group was significantly (p < 0.05) increased. The daily milk yield, 6% fat corrected milk (FCM) yield and immune response were also increased (p < 0.05) in CFA group. The study suggests that the supplementation of composite feed additive was effective to reduce enteric methane emissions and improvement in production performance and immune status of buffaloes.