Efficacy of formic acid in combination with cDMARDs in rheumatoid arthritis.

OBJECTIVE: The immune system of the body mistakenly targets its own joints in rheumatoid arthritis (RA), a chronic autoimmune disease that causes pain, inflammation, and damage. The complexity of RA often requires the simultaneous use of several different management strategies. This study examines the potential enhancement of conventional RA treatments, specifically conventional Disease-Modifying Anti-Rheumatic Drugs (cDMARDs), by the addition of formic acid, a naturally occurring substance that may possess anti-inflammatory properties. PATIENTS AND METHODS: A total of 90 children diagnosed with rheumatoid arthritis were examined at our hospital from 2020 to 2022. We segregated them into two cohorts, each consisting of 45 children. One cohort was administered conventional rheumatoid arthritis (RA) treatments, referred to as cDMARDs, which specifically included methotrexate and leflunomide. The other group was administered the standard treatments in addition to a low dosage of a specialized medication known as all-trans retinoic acid. We conducted follow-up assessments on the children at 6 months and 1-year post-treatment. We sought to evaluate the efficacy of the treatments by assessing the subjective reports of the children and their physicians, analyzing the outcomes of medical examinations, and examining diagnostic images, such as X-rays. Furthermore, we took measures to ensure the safety of the treatments. RESULTS: Among the cohort exclusively administered cDMARDs, approximately 26.7% exhibited significant improvement, 24.4% demonstrated moderate improvement, and 6.7% displayed minor improvement after a duration of 6 months. Approximately 57.8% of the children in this group experienced positive outcomes as a result of the treatment. The group that received retinoic acid also demonstrated superior outcomes. Approximately one-third (33.3%) of the participants demonstrated significant improvement, while another one-third showed moderate improvement. Additionally, 11.1% of the participants displayed minor improvement after a period of six months. Upon comparing the two groups, it was observed that the group receiving retinoic acid demonstrated a significantly superior outcome (p<0.05). CONCLUSIONS: Overall, the incorporation of all-trans retinoic acid alongside conventional treatments for children with RA appears to enhance their efficacy.

Dietary concoction of formic acid and thymol and its effects on zoo-technical performance, immunity, jejunal architecture and gut health in Turkey.

With increasing demand for improved protein-rich food, diverse poultry birds like turkey are gaining popularity in India. However, with the rising concerns of antibiotic residues and drug resistance, safe alternatives like formic acid (FA) and thymol (TH) have attracted the attention of researchers as effective replacer of antibiotic growth promoters (AGP). This experiment investigated the effects of combinations of FA and TH on growth performance, immunity, gut microflora and jejunal microstructures in turkey. A total of 240 turkey poults were reared in 6 treatment groups for a period of 16 weeks with standard management and feeding: T1 (basal diet only); T2 (AGP); T3 (FA@2.5 ml + TH@240 mg/kg); T4 (FA@2.5 ml + TH@360 mg/kg); T5 (FA@7.5 ml + TH@240 mg/kg) and T6 (FA@7.5 ml + TH@360 mg/kg). The results revealed that T5 group had the highest final body weight and best FCR while the feed consumption across the groups was comparable. The immune status of the turkey improved (p ≤ 0.05) in treatment groups compared to control with T4 and T5 group showcasing the best CBH response, antibody titres and relative immune organ weight index. A significant improvement (p ≤ 0.05) in jejunal microstructures was observed at 16th week in T5 group over control and AGP fed group. There was significant (p ≤ 0.001) reduction in total plate and coliform counts, but a positive shift was seen in Lactobacillus population in T5 group as compared to control and AGP fed group. In conclusion, the concoction of formic acid (7.5 ml/kg) + thymol (240 mg/kg) in-feed supplement improved the performance, immune status and gut health in turkey as an efficient alternative to AGPs.

Effect of dietary calcium source, exogenous phytase, and formic acid on inositol phosphate degradation, mineral and amino acid digestibility, and microbiota in growing pigs.

The choice of the calcium (Ca) source in pig diets and the addition of formic acid may affect the gastrointestinal inositol phosphate (InsP) degradation and thereby, phosphorus (P) digestibility in pigs. This study assessed the effects of different Ca sources (Ca carbonate, Ca formate), exogenous phytase, and chemical acidification on InsP degradation, nutrient digestion and retention, blood metabolites, and microbiota composition in growing pigs. In a randomized design, 8 ileal-cannulated barrows (24 kg initial BW) were fed 5 diets containing Ca formate or Ca carbonate as the only mineral Ca addition, with or without 1,500 FTU/kg of an exogenous hybrid 6-phytase. A fifth diet was composed of Ca carbonate with phytase but with 8 g formic acid/kg diet. No mineral P was added to the diets. Prececal InsP6 disappearance and P digestibility were lower (P ≤ 0.032) in pigs fed diets containing Ca formate. In the presence of exogenous phytase, InsP5 and InsP4 concentrations in the ileal digesta were lower (P ≤ 0.019) with Ca carbonate than Ca formate. The addition of formic acid to Ca carbonate with phytase diet resulted in greater (P = 0.027) prececal InsP6 disappearance (87% vs. 80%), lower (P = 0.001) InsP5 concentration, and greater (P ≤ 0.031) InsP2 and myo-inositol concentrations in the ileal digesta. Prececal P digestibility was greater (P = 0.004) with the addition of formic acid compared to Ca carbonate with phytase alone. Prececal amino acid (AA) digestibility of some AA was greater with Ca formate compared to Ca carbonate but only in diets with phytase (P ≤ 0.048). The addition of formic acid to the diet with Ca carbonate and phytase increased (P ≤ 0.006) the prececal AA digestibility of most indispensable AA. Exogenous phytase affected more microbial genera in the feces when Ca formate was used compared to Ca carbonate. In the ileal digesta, the Ca carbonate diet supplemented with formic acid and phytase led to a similar microbial community as the Ca formate diets. In conclusion, Ca formate reduced prececal InsP6 degradation and P digestibility, but might be of advantage in regard to prececal AA digestibility in pigs compared to Ca carbonate when exogenous phytase is added. The addition of formic acid to Ca carbonate with phytase, however, resulted in greater InsP6 disappearance, P and AA digestibility values, and changed ileal microbiota composition compared to Ca carbonate with phytase alone.

The study aimed to investigate the effects of dietary calcium sources, exogenous phytase, and formic acid on inositol phosphate (InsP) degradation and nutrient digestibility in ileal-cannulated growing pigs. It also evaluated the concentrations of phosphorus, calcium, and myo-inositol in the blood, the composition of the microbiota in the ileal digesta and feces, and the concentrations of volatile fatty acids in the feces. Replacing calcium carbonate with calcium formate in the feed reduced prececal InsP6 disappearance and phosphorus digestibility. However, adding formic acid to a diet containing calcium carbonate and phytase enhanced prececal InsP6 disappearance and phosphorus digestibility, and increased InsP2 and myo-inositol concentrations in the ileal digesta. The dietary treatments resulted in more pronounced alterations of the microbiota in the feces than the ileal digesta. In ileal digesta, the shifts in relative abundance were primarily evident among low-abundant genera, while in feces, changes were observed in a larger number among genera with higher levels of abundance. The findings of this study suggest that calcium formate is not a suitable alternative to calcium carbonate for phosphorus digestibility in growing pigs. The release of phosphorus from InsP by exogenous phytase can be increased by adding formic acid.

Formic acid as an antibiotic alternative in broiler diets: effects on growth, carcass characteristics, blood chemistry, and intestinal microbial load.

This study explored the ability of formic acid (FA) to replace antibiotics in broiler chicken diets. It examined how FA affected the chickens' growth, carcass characteristics, blood chemistry, and gut bacteria. The experiment randomly assigned 300 one-day-old (Ross 308) broiler chicks to 5 groups, each divided into 6 replicates with 10 unsexed chicks. The following were the treatments: 1st group, negative control (NC): only received a basal diet; 2nd group, positive control (PC): received a basal diet supplemented with 0.5 grams of Colistin antibiotic per kilogram of diet; 3rd, 4th, and 5th groups (FA2, FA4, and FA6) these groups received a basal diet along with formic acid added at increasing levels: 2, 4, and 6 Cm3 per kilogram of diet, respectively. Results found no significant differences in live body weight (LBW) or body weight gain (BWG) between treatment groups, except for LBW at one week and BWG at 0 to 1 and 4 to 5 wk of age. No significant variations were found in feed intake (FI) and feed conversion ratio (FCR) among the treatment groups, excluding FI and FCR at 1 to 2 wk of age. The treatments significantly impacted carcass traits, dressing percentage, breast meat, thigh meat, spleen, giblets, blood levels of urea, creatinine, total protein, globulin, and albumin, as well as the activity of enzymes alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in chicks fed different diets compared to control groups. The addition of FA to the diet significantly impacted antioxidant levels. Also, the FA2 group had the highest total bacterial count (TBC). However, the FA6 group was the opposite; it had the lowest levels of harmful bacteria, such as E. coli and Coliform. Supplementing broiler diets with formic acid improves blood parameters, antioxidant activity, and gut bacteria counts, with 4.0 cm³ formic acid/kg diet supplementation promoting optimal broiler health and product quality.

Evaluation of in-feed supplementation of formic acid and thymol as non-antibiotic growth promoters and assessing their effect on antimicrobial resistant E.coli isolated in Turkey.

With the rampant usage of antibiotics as growth promoters (AGPs) in poultry sector, there has been alarming concerns of antimicrobial resistant microbes such as Escherichia coli. Diversification of poultry farming due to consumer demand for safer products with higher protein content, turkey production is gaining popularity. Feed additives such as formic acid (FA) and thymol (TH) are effectively replacing AGPs due to their antimicrobial action. This directed the researchers to find alternatives to antibiotics such as thymol and formic acid because of their strong antimicrobial, anti-oxidative, digestive-stimulating properties. To assess the efficacy of FA and TH as growth promoters and their effect on the antimicrobial resistance (AMR) load, the current study (0-12 weeks) was conducted in CARI VIRAT turkey poults (n = 256; unsexed) those were randomly distributed into eight treatment groups: control(T1), AGP (T2), graded levels of FA (T3 to T5) @ 2.5, 5 and 7.5 ml/kg and TH (T6 to T8) @ 120, 240 and 350 mg/kg. Cloacal swab samples were collected at 0, 4th, 8th and 12th week interval and processed further for isolation, identification and assessment of resistance profile of E. coli. The final body weight, cumulative gain and FCR were significantly (p < 0.05) better for birds under supplementation. The Total plate count (TPC) and coliforms showcased a significant (p < 0.001) reduction in the FA and TH supplement groups as compared to control and AGP group. The resistance profile indicated E. coli isolates from AGP group with significantly (p < 0.001) highest resistivity against antibiotics (viz. chloramphenicol, tetracycline, nalidixic acid, chlortetracycline) while isolates from FA (T5) and TH (T8) groups were the least resistant. blaAmpC gene was significantly (p < 0.001) harbored in T2 isolates whereas least detected in T5 and T8. It was inferred that formic acid (7.5 ml/kg) and thymol (360 mg/kg) can effectively replace AGPs and lower AMR burden in poultry.

Effects of dietary organic acids on performance, cecal microbiota, and gut morphology in broilers.

Organic acids have exhibited great potential as an antibiotic replacement and as an additive work tremendously for health maintenance of broiler chicken. To explore more about organic acids, a total of 900 day-old broiler chicks (Cobb-500) were procured from a local hatchery and distributed into 9 treatment groups having 5 replicates of 20 birds each; duration of the biological trial was of 35 days. Group T1 served as control group without any dietary supplementation. Other groups T2 and T3 were boosted with different levels (125 g/ton and 250 g/ton) of enramycin (antibiotic), T4, T5, and T6 were supplemented with different levels (2 kg/ton, 3 kg/ton, and 4 kg/ton) of ammonium formate and ammonium propionate, and T7, T8, and T9 were fed with different levels (2 kg/ton, 3 kg/ton, and 4 kg/ton) of calcium formate and calcium propionate. The findings declared significant improvement (P < 0.05) in body weight gain and FCR in groups T3, T5, and T9 while feed intake was not affected. Carcass evaluation depicted significantly better (P < 0.05) dressed and eviscerated weight along with carcass yield (T5, T7, T8, T9). Broilers fed organic acid supplemented diet had significantly lower (P < 0.05) total bacterial count (T3, T5, T8, T9) and positively improved (P < 0.05) villi length (T5, T6, T9) as compared with control group. However, total protein, globulin, HDL, and LDL levels were determined to be non-significant (P > 0.05) among different organic acids treatments. Hence, organic acids can be utilized as a better replacement for antibiotics. Supplementation of organic acids at a dose rate of 3 kg/ton and 4 kg/ton is recommended for efficient performance of broilers.

Research Note: Effect of organic acid mixture on growth performance and Salmonella Typhimurium colonization in broiler chickens.

Feed additives can be alternatives to antibiotics for routinely encountered pathogens in the poultry production. The objective of this study was to understand effects of organic acid mixture on growth parameters and Salmonella Typhimurium (ST) colonization in broilers. Organic acid mixture is a feed-grade buffered formic acid and sodium formate mixture (Amasil NA). A total of 800 1-day-old Cobb500 males were fed one of the five dietary treatments: a negative control diet without ST challenge (NC), positive control diet with ST challenge (PC), 0.3% organic acid mixture with ST, 0.6% organic acid mixture with ST, and 0.9% organic acid mixture with ST. Treatments were assigned to 20 pens with 40 chicks/pen and 4 replicates of each treatment. Chickens were challenged with 107 CFU/mL of nalidixic acid-resistant ST (STNAR) 4-D posthatch. In the grower phase, feed conversion rate was significantly reduced in the 9% organic acid mixture compared with the PC. The body weight and body weight gain (BWG) were not affected either in the starter or grower phases. However, in the finisher phase, the nonchallenged NC had higher BWG than the PC (P < 0.05), whereas there were no differences in BWG among the NC and organic acid mixture fed groups. In addition, there was a significant effect of organic acid mixture on the colonization of cecal STNAR. At 9 dpi, cecal STNAR was 3.28 log10 in the PC that was reduced to 2.65 log10 at 0.3%, 1.40 log10 at 0.6%, and 0.84 log10 in 0.9% organic acid mixture. At 24 dpi, cecal STNAR recovery was 0.81, 0.99, 0.53, and 0.33 log10 in the PC and 0.3, 0.6, and 0.9% organic acid mixture, respectively. Similarly, at 38 dpi, cecal STNAR was 0.26, 0.11, 0.33, and 0 log10 in the PC, 0.3, 0.6, and 0.9%, respectively. These results show that organic acid mixture can be one dietary strategy to control ST infection and maintain efficient growth performance.

Combined and Singular Effects of Dietary PrimaLac® and Potassium Diformate (KDF) on Growth Performance and Some Physiological Parameters of Rainbow Trout (Oncorhynchus mykiss).

The present study was conducted to assess the effects of combined and singular dietary administration of PrimaLac® and potassium diformate (KDF) on growth performance, feed utilization, digestive enzymes activity, and some physiological parameters of rainbow trout (Oncorhynchus mykiss) juvenile. Three hundred sixty rainbow trout juveniles (25 ± 1.8 g) were randomly stocked in 300-L tanks (30 fish/tank), and fed three times daily on a basal diet (control), diets incorporated with 12 g kg-1 KDF (FT1), 1.5 g kg-1 PrimaLac® (FT2), and combination of 1.5 g kg-1 probiotic and 12 g kg-1 KDF (FT3) in triplicates, for 8 weeks. At the end of feeding trial, growth performance, body composition, digestive enzymes, liver enzymes, and biochemical parameters were measured. Our results revealed that combined administration of PrimaLac® and KDF (FT3) exhibited significantly higher weight gain and specific growth rate (SGR) compared to other groups (P < 0.05). Glucose and cortisol levels showed no significant differences between fish fed different test diets (P > 0.05). The highest lipase, protease and amylase activity were observed in group of fish fed FT3 followed by FT2 and FT1. Besides, the diets FT2 and FT3 led to significantly lower of ALP, ALT, and AST compared to control group. The present results indicated that combined administration of PrimaLac® and KDF can be considered as a beneficial feed additive and growth promotor for O. mykiss juvenile.

Effects of a phytogenic, alone and associated with potassium diformate, on tilapia growth, immunity, gut microbiome and resistance against francisellosis.

This work evaluated the effects of dietary supplementation of A-Live (phytogenic) either individually or in combination with Aquaform (potassium diformate, acidifier) on juvenile Nile tilapia (Oreochromis niloticus) growth performance, innate immune parameters, gut microbiome, and resistance against Francisella noatunensis subsp. orientalis challenge. Each experimental group contained 140 fishes (34.3 ± 0.33) in two 150L tanks. The experimental design consisted of five groups: a negative control; treated groups (G1, G2, G3) supplemented with different concentrations of A-Live and Aquaform in the feed; and a positive control (PC) for pathogen infection. Groups G1, G2, G3, and PC were challenged with Francisella spp. after 15 days. After infection, the mortality was significantly lower in groups G1, G2, and G3 (p < 0.01). Furthermore, these groups showed significant increase (p < 0.05) in daily weight gain, feed conversion rate, and specific growth rate. The PC group presented increase (p < 0.05) in the leukocytes and neutrophils number. Innate immunity parameters showed no difference between treatments after infection. Microbiome analysis revealed an increased number of bacteria belonging to the Vibrionaceae family after pathogen infection suggesting a secondary pathogen function of these bacteria. These results validate the beneficial effects of these products in tilapia farming.

Lethality of synthetic and natural acaricides to worker honey bees (Apis mellifera) and their impact on the expression of health and detoxification-related genes.

In this study, honey bees (Apis mellifera L.) were exposed to LD05 and LD50 doses of five commonly used acaricides for controlling the parasitic mite, Varroa destructor. LD50 values at 48 h post-treatment showed that tau-fluvalinate was the most toxic, followed by amitraz, coumaphos, thymol, and formic acid. However, the hazard ratios, which estimate the hive risk level based on a ratio of a standard dose of acaricide per hive to the LD50 of the acaricide, revealed that tau-fluvalinate was the most hazardous followed by formic acid, coumaphos, amitraz, and thymol. The expression of the honey bee acetylcholinesterase gene increased after treatment with the LD05 and LD50 acaricide doses and could distinguish three patterns in the timing and level of increased expression between acaricides: one for amitraz, one for tau-fluvalinate and formic acid, and one for coumaphos and thymol. Conversely, changes in cytochrome P450 gene expression could also be detected in response to all five acaricides, but there were no significant differences between them. Changes in vitellogenin gene expression could only detect the effects of tau-fluvalinate, amitraz, or coumaphos treatment, which were not significantly different from each other. Among the acaricides tested, coumaphos, amitraz, and thymol appear to be the safest acaricides based on their hazard ratios, and a good marker to detect differences between the effects of sub-lethal doses of acaricides is monitoring changes in acetylcholinesterase gene expression.

Evaluation of the addition of organic acids in the feed and/or water for broilers and the subsequent recovery of Salmonella Typhimurium from litter and ceca.

Three separate broiler Salmonella Typhimurium challenge experiments were conducted evaluating efficacy of formic and propionic acid feed supplements to suppress environmental and cecal Salmonella Typhimurium prevalence. In experiment 1, broilers were provided feed with 1 kg/ton formic acid or 5 kg/ton propionic acid feed additives or a basal control diet. At the day of placement, half of the pens were inoculated with seeder chicks orally challenged with a marker strain of Salmonella Typhimurium and to yield challenged and adjacent nonchallenged pens. No differences in weekly litter samples or cecal Salmonella prevalence at 3 or 6 wk among feeding treatments were detected. In experiment 2, treatments were: 2 kg/ton propionic acid in feed, 1.0 mL/L formic acid in water, both propionic acid in feed and formic acid in water, and a basal control. Every pen was challenged with seeder chicks inoculated with Salmonella Typhimurium. By 6 wk all pens maintained detectable litter Salmonella, and broilers provided both propionic acid in feed and formic acid in water had the lowest cecal recovery (35%), compared to the control (60%). In experiment 3, treatments were: formic acid at 4 or 6 kg/ton from wk 0 to 6 or for only the last wk, propionic acid at 5 or 10 kg/ton for only the last wk, and a basal control. Each pen was challenged with Salmonella Typhimurium inoculated seeder chicks. By 6 wk, broilers fed formic acid (4 kg/ton) for the entire growout had no Salmonella-positive ceca (0/30). All treatments that provided acid supplemented feed for only the last wk had 3-13% Salmonella-positive ceca. These experiments indicate that adding formic acid to broiler feed appears to prevent Salmonella colonization from challenge pens entering into the adjacent nonchallenge pens. Feeding formic acid (4 kg/ton) for 6 wk resulted in no recovery of Salmonella from ceca compared to the control prevalence of 17%.

Effect of an organic acids based feed additive and enrofloxacin on the prevalence of antibiotic-resistant E. coli in cecum of broilers.

Increasing antibiotic resistance is a major public health concern. Fluoroquinolones are used to treat and prevent poultry diseases worldwide. Fluoroquinolone resistance rates are high in their countries of use. The aim of this study was to evaluate the effect of an acids-based feed additive, as well as fluoroquinolone antibiotics, on the prevalence of antibiotic-resistant E. coli. A total of 480 broiler chickens (Ross 308) were randomly assigned to 3 treatments: a control group receiving a basal diet; a group receiving a feed additive (FA) based on formic acid, acetic acid and propionic acid; and an antibiotic enrofloxacin (AB) group given the same diet, but supplemented with enrofloxacin in water. A pooled fecal sample of one-day-old chicks was collected upon arrival at the experimental farm. On d 17 and d 38 of the trial, cecal samples from each of the 8 pens were taken, and the count of E. coli and antibiotic-resistant E. coli was determined.The results of the present study show a high prevalence of antibiotic-resistant E. coli in one-day-old chicks. Supplementation of the diet with FA and treatment of broilers with AB did not have a significant influence on the total number of E. coli in the cecal content on d 17 and d 38 of the trial. Supplementation with FA contributed to better growth performance and to a significant decrease (P ≤ 0.05) in E. coli resistant to ampicillin and tetracycline compared to the control and AB groups, as well as to a decrease (P ≤ 0.05) in sulfamethoxazole and ciprofloxacin-resistant E. coli compared to the AB group. Treatment with AB increased (P ≤ 0.05) the average daily weight compared to the control group and increased (P ≤ 0.05) the number of E. coli resistant to ciprofloxacin, streptomycin, sulfamethoxazole and tetracycline; it also decreased (P ≤ 0.05) the number of E. coli resistant to cefotaxime and extended spectrum beta-lactamase- (ESBL-) producing E. coli in the ceca of broilers.

Investigation of in-feed organic acids as a low cost strategy to combat Salmonella in grower pigs.

Salmonella carriage in pigs is a significant food safety issue. Dietary supplementation with organic acids has previously been shown to reduce shedding and transmission of Salmonella. Therefore, this study aimed to examine the effect of three commercially available organic acid-based products on Salmonella levels in grower pigs, using a model of experimental infection that closely mimics natural exposure to the organism. Seven week old trial pigs (n=40) with a mean weight of 14.7kg were placed in one of four pens with 10 pigs/pen. Pens had previously been contaminated with Salmonella Typhimurium 4,[5],12;i;- via seeder pigs. Trial pigs received one of four diets for 28days: 1, control diet; 2, sodium butyrate supplemented diet; 3, benzoic acid supplemented diet and 4, formic-citric acid supplemented diet. A further 10 pigs were placed in a Salmonella-free pen receiving the control diet. Pigs were weighed and blood sampled on days 0 and 28. Faeces was collected on day 0, 2, 3, 5, 7, 14, 21 and 28 and examined for Salmonella. On day 28, 5 pigs/group were euthanised and ileocaecal lymph nodes (ILN) and caecal contents sampled for culture. The remaining 5 pigs/pen were then fed the control diet and faeces were collected on days 35 and 42. On day 42 pigs were euthanised and ILN and caecal contents tested for Salmonella levels. The trial was repeated once. Within the first two days of exposure to the contaminated environment, 96% (77/80) of pigs became infected. Most pigs shed Salmonella at levels of between 100-103 CFU/g faeces for at least 7days post-exposure. A significant reduction in Salmonella faecal concentration was observed after supplementation with sodium butyrate (p=0.001) and a formic citric acid blend (p<0.0001). Average daily weight gain (ADWG) was significantly increased in all groups fed the supplemented feed when compared to the positive control group. The use of sodium butyrate or a blend of formic and citric acid in feed could be considered a cost-effective control measure to reduce Salmonella faecal shedding and improve ADWG in Salmonella infected herds.

Effects of commercial organic acid blends on male broilers challenged with E. coli K88: Performance, microbiology, intestinal morphology, and immune response.

This study assessed the effects of 3 commercial organic acid (OA) preparations on growth performance, intestinal morphology, cecal microbiology, and immunity of Escherichia coli K88-challenged (ETEC) broiler chickens. One thousand one-day-old male broiler chickens were divided into 8 treatments of 5 replicate pens: Negative control (NC) birds received a basal diet (BD) and were not challenged with ETEC; positive control (PC) birds fed the BD and challenged with ETEC; BD + 0.2% (S1) or 0.4% (S2) of an OA mixture (Salkil) from one to 35 d; BD + 0.1, 0.075, and 0.05% (O1) of another OA mixture (Optimax) in the starter (one to 10 d), grower (11 to 24 d), and finisher (25 to 35 d) diets, respectively, or 0.1% (O2) from one to 35 d; BD + 0.07, 0.05, and 0.05% (P1) or 0.1, 0.07, and 0.05% (P2) of a further OA mixture (pHorce) in the starter, grower, and finisher diets, respectively. All groups (not NC) were challenged with one mL of ETEC (1 × 108 cfu/mL) at 7 d of age. The 3 OA mixtures are commercial formic and propionic acid preparations. Birds challenged with ETEC (PC) had reduced (P < 0.05) growth performance, ileal morphological parameters (not crypt depth, which was increased), cecal lactobacilli, and immune responses, and increased cecal E. coli compared with unchallenged, NC birds. The addition of OA to the diets of ETEC challenged birds (S1-P2) either numerically or significantly (P < 0.05) improved growth performance, ileal morphology and immune responses, increased cecal lactobacilli, and reduced cecal E. coli. For most OA additions, the assessed parameters were generally enhanced to equivalence to NC birds. The results suggest that dietary OA supplementation can enhance the growth performance, ileal morphology, cecal microbiota, and immunity of ETEC-challenged broilers to an extent that, under such circumstances, the formulations used in this study provided similar performance and assessed parameters as non-challenged birds.

H9N2-specific IgG and CD4+CD25+ T cells in broilers fed a diet supplemented with organic acids.

Organic acids have long been known for their beneficial effects on growth performance in domestic animals. However, their impact on immune responses against viral antigens in chickens is unclear. The present study aimed to investigate immunological parameters in broilers immunized with a H9N2 vaccine and/or fed a diet containing organic acids (citric, formic, and lactic acids). We allotted 1-day-old broilers into 4 groups: control (C), fed a diet supplemented with organic acids (O), administered a H9N2 vaccine (V), and fed a diet supplemented with organic acids and administered a H9N2 vaccine (OV). Blood and spleen samples were taken at 2, 7 and 14 d post vaccination (DPV). At 14 DPV, total and H9N2-specific IgG levels were significantly lower in the OV group than in the V group. However, it was intriguing to observe that at 2 DPV, the percentage of CD4+CD25+ T cells was significantly higher in the OV group than in the other groups, indicating the potential induction of regulatory T cells by organic acids. In contrast, at 2 DPV, the percentage of CD4+CD28+ T cells were significantly lower in the OV group than in the other groups, suggesting that CD28 molecules are down-regulated by the treatment. The expression of CD28 on CD4+ T cells, up-regulated by the stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Iono), was inhibited upon organic acid treatment in OV group. In addition, the proliferation of lymphocytes, stimulated with formalin-inactivated H9N2, was significantly higher in the V group than in the OV group. Alpha 1-acid glycoprotein (AGP) production was significantly lower in the OV group than in the V group, suggesting that the organic acids inhibited the inflammation caused by the vaccination. Overall, induction of regulatory CD4+CD25+ T cells, coinciding with the decrease of H9N2-specific antibodies, was observed in broilers fed organic acids.

Effect of strategic administration of an encapsulated blend of formic acid, citric acid, and essential oils on Salmonella carriage, seroprevalence, and growth of finishing pigs.

Controlling Salmonella at farm level can act as the first line of defence in reducing salmonellosis from pork. This study investigated the efficacy of an encapsulated blend of formic acid, citric acid, and essential oils (FormaXOL™) administered to finisher pigs for 28days prior to slaughter in controlling Salmonella shedding on a commercial farm with a history of high Salmonella seroprevalence. Fourteen pens of 8-10 pigs/pen were randomly assigned to a control (finisher diet without additive) or a treatment group (the same diet with 4kg/t of FormaXOL™) for 28 days. Faeces were collected from each pig on days 0, 14, and 28, while on day 29 blood, caecal digesta and ileocaecal-mesenteric lymph nodes were collected at slaughter. Pigs were weighed at the start and end of the trial, feed intake was recorded, and carcass quality parameters were recorded at slaughter. On day 14, Salmonella shedding was reduced in the treatment compared to the control group (27.9% versus 51.7% probability of detecting Salmonella in faeces, respectively; p=0.001). However, on day 28, no reduction was observed (20.6% versus 35.9% probability of detecting Salmonella in faeces, respectively; p=0.07). Interestingly, Salmonella shedding rates in the treated pigs remained stable throughout the trial compared to the control group. This suggests that the feed additive prevented additional pigs from acquiring the Salmonella infection. A lower Salmonella seroprevalence was detected at slaughter in the treatment compared to the control group using the 40% optical density cut-off (64.5% versus 88.5%, respectively; p=0.01). However, no significant differences in Salmonella recovery rates were observed in the caecal digesta or lymph nodes between treated and control groups. Treated pigs had a lower feed intake than pigs fed the control diet (p=0.001); however, average daily gain and feed conversion efficiency were not affected by treatment (p=0.45 and 0.55, respectively). Consequently, supplementing the diet with FormaXOL™ for 28days increased the feed cost per kg of live-weight gain by €0.08. Overall, results suggest that strategic administration of an encapsulated blend of formic acid, citric acid, and essential oils, to finishing pigs for 28days prior to slaughter has potential to prevent increased Salmonella shedding at certain time points as well as seroprevalence. However, this additive did not lower intestinal carriage, nor did it reduce seroprevalence to below the cut-off used for the high Salmonella risk category in Ireland (50%) or improve growth performance.

Effects Induced by Organic Acids in a Human Lung Alveolar Carcinoma Cell Line A549.

The present study examined the effects of formic acid and acetic acid on human adenocarcinoma-derived alveolar basal epithelial A549 cells. The organic acids were administered either individually or in combination, into either the culture medium (aqueous phase) or the gaseous phase of an air-liquid interface. When either of the acids was administered into the aqueous phase, cell proliferation was inhibited at doses of 1-10 mg/mL. In contrast, when the acids were administered either individually or in combination, into the gaseous phase of the air-liquid interface, cell proliferation was not altered. Under the gaseous phase administration, acetic acid and mixed acids caused a slight increase, decrease and increase on the interleukin-8 production, the mRNA expression of the heme oxygenase-1 (HO-1) gene and the HO-1 production, respectively, at one or more time points. The results therefore indicated that organic acids might be less reactive in the gaseous phase than in the aqueous phase. However, acetic acid in the gaseous phase either individually or in combination with formic acid exerts some effects on A549 cells.

Effects of dietary acidifiers on growth, hematology, immune response and disease resistance of Nile tilapia, Oreochromis niloticus.

Organic acids or their salts can be used as feed additives in aquaculture. This study was conducted to evaluate the use of a mixture of formic acid, propionic acid and calcium propionate compared with oxytetracycline (OTC). A total of 720 apparently healthy Oreochromis niloticus fingerlings with an average body weight of 28.8 ± 0.14 g (mean ± SE) were randomly divided into four equal groups (G1, G2, G3and G4). G1 was fed a basal diet with no additive as the control group, while G2 and G3 were fed a formic and propionic acid/salt mixture in 1 and 2 g/kg, respectively. G4 was fed OTC (0.5 g/kg). Each group was subdivided into tow subgroups A and B (30 fish/subgroup) in triplicate. The first subgroup was used to evaluate growth performance, hematology and body composition for 60 d. The second subgroup was used to examine immunity, gut microbiota and resistance to infection for 30 d. At the end of the feeding period (60 d), G3 had significant improvements in final body weight (FBW), weight gain (WG), specific growth rate (SGR) and food conversion ratio (FCR) compared with other groups. The total erythrocyte count, hemoglobin content, platelet count, hematocrit, mean corpuscular hemoglobin and total leukocyte count were significantly increased in G3 and G2 compared with G1 and G4. Mean corpuscular volum, lymphocyte and neutrophil percentages had the highest significant improvement in G3. There were no significant differences among the groups in mean corpuscular hemoglobin concentration and monocyte percentage. The protein and fat contents of the whole body were the highest in G3. The widest inhibition zones against Aeromonas sobria were at the 30, 40 and 50% concentrations of acidifiers, which were equivalent to OTC (30 µg). G3 showed the lowest total gastrointestinal bacterial counts, followed by G2. After 15 and 30 d, G3 had the highest serum killing, lysozyme and nitric oxide activities. Serum lysozyme activity and nitric oxide assay had no significant difference between G1 and G2 after 30 d. The lowest immune parameters were recorded in G4. After 30 d, the highest expression of interleukin-1ß and tumor necrosis factor-alpha in the liver and kidney were found in G3. The best protection against challenged Aeromonas sobria was in G3, followed by G2 and G4. Dietary supplementation with a combination of formic acid, propionic acid and calcium propionate improves the performance of Nile tilapia.

Influence of an organic acid blend and essential oil blend, individually or in combination, on growth performance, carcass parameters, apparent digestibility, intestinal microflora and intestinal morphology of broilers.

This study aimed to evaluate the influence of an organic acid (OA) and essential oil (EO) blends, individually or in combination, on growth performance, carcass parameters, apparent digestibility, intestinal microflora and intestinal morphology of broilers. A total of 480 one-d-old male Ross 308 chicks were randomly assigned to 4 treatments consisting of 4 replicates each (n = 30 birds in each replicate). Dietary treatments consisted of a basal diet (control), and basal diet supplemented with 2 g/kg OA blend (OAB), 300 mg/kg EO blend (EOB), or with 2 g/kg OA and 300 mg/kg EO blend (OAB-EOB) for 42 d. The dietary supplementation with EO blend or in combination with OA blend increased body weight gain and improved feed efficiency as compared to control. Dietary treatments had no significant effects on feed consumption or relative organ weights of broilers. The OAB diet increased carcass yield compared to the control diet but the lowest carcass yield occurred with the OAB-EOB combination. Birds fed on EOB and OAB-EOB diets had lower ileum Escherichia coli counts than birds fed on the control diet. There was no significant effect of treatments on apparent digestibility at 16-21 d but the EOB and OAB-EOB diets increased apparent digestibility of dry matter and crude protein during the finisher period (d 37-42) compared to the control diet. Birds fed on the EOB and OAB-EOB diets had greater villus height in the ileum at 21 and 42 d of age and had lower crypt depth in the ileum at 42 d of age than birds given the control diet. In conclusion, beneficial effects of the use of EO blend individually or in combination with the OA blend were observed but the OA blend alone was ineffective. Furthermore, the use of the combination of OA and EO was more effective, in some respects, than their individual use.