Effect of organic acids on growth performance, intestinal morphology, and immunity of broiler chickens with and without coccidial challenge

A total of 360-day-old broiler chicks were allocated into six groups in 2 (Coccidial challenge or not) × 3 (dietary treatments) factorial design. Three dietary treatments including: basic diet, basic diet plus organic acids (OAs) in drinking water, and basic diet plus OAs in the feed with and without coccidial challenge. The OAs in water or feed improved (P < 0.01) average body weight (ABW), average body weight gain (ABWG), and feed conversion ratio (FCR) as compared with the control diet during starter, grower, and whole experimental period. Coccidial challenge decreased BW, ABWG, and average feed intake (AFI), as well as resulted in poor FCR during the starter and whole experimental period (P < 0.05). Though there was no interaction between OAs supplementation and coccidial challenge, the OAs supplementation improved the overall performance with and without coccidial challenge birds on 21 d and 35 d. IgG was found higher (P = 0.03) in broilers fed OAs in feed without the coccidial challenge group. On 18 d, OAs supplementation in feed increased TNF-γ (P = 0.006), whereas the coccidial challenge decreases TNF-γ (P = 0.01) and IL-10 (P = < .0001), and increases IgM (P = 0.03), IgG (P = 0.04) and IgA (P = 0.02). On 29 d, the coccidial challenge increases IgM and IgA. On 18 d, jejunal lesion score was found significantly higher in the coccidial challenged group as compared to OAs supplementation with coccidial challenged groups on 18 d (P < 0.0001) and 29 d (P = 0.03). Crypt depth was higher, and Villus-height to Crypt depth ratio was lower in the coccidial challenge group on 18 and 29 d. The Goblet cells were found higher in the non-coccidial challenge on 18 d. After 18 d, 16S rDNA gene sequence analysis of ileal chyme has shown that coccidial challenge decreases Lactobacillus_reuteri species as compared to the non-challenged group (P = 0.02). After 29, Cyanobacteria abundance reduced (P = 0.014) in the challenged group than the non-challenged group at the phylum level. At the genus level, Lactobacillus (P = 0.036) and unidentified Cyanobacteria (P = 0.01) were found higher in the non-challenged group than the coccidial challenge group. The results indicate that the OAs supplementation showed improved responses in a pattern similar to the non-challenged control group by neutralizing the negative effects of the coccidial challenge.

Determination of isoprostane 8‐iso‐PGF2α and prostaglandin GF2α in plasma and intestine of specific-pathogen-free chickens challenged with Eimeria maxima

The purpose of this study was to evaluate and determine the concentration of isoprostane 8‐iso‐PGF2α and prostaglandin GF2α (PGF2α) from plasma and intestine in specific pathogen-free (SPF) chickens challenged with Eimeria maxima (EM) using solid‐phase microextraction and ultra‐performance liquid chromatography/tandem mass spectrometry. Forty one-day-old male SPF chickens were randomly allocated to one of two groups with four replicates (n=5 chickens/replicate). Groups consisted of Control (no challenge) or the Challenge group EM (40,000 sporulated oocysts/bird). At day 7 and 9 post-challenge, half of the chickens were euthanized in both groups to determine plasmatic and enteric concentrations of isoprostane 8‐iso‐PGF2α and PGF2α. Enteric levels of both 8‐iso‐PGF2α and PGF2α were significantly increased at 7 (8‐iso‐PGF2α P=0.0000252; PGF2α P=0.00000268) and 9 days (8‐iso‐PGF2α P=0.000000717; PGF2α P=0.00000222) post-challenge compared to non-challenge control chickens. However, plasma levels of isoprostane 8‐iso‐PGF2α and PGF2α were similar in both groups. A significant reduction (P=0.0000095) in oocyst excretion was observed in chickens at 9 days post-challenge compared to 7 days. Chickens challenged with EM showed an inflammatory response associated with significant increases in enteric PGF2α and 8-Iso-PGF2α, suggesting that the active disease phase was accompanied by inflammation and oxidative stress within the intestinal layer.

Incorporating highly-basic polyoxometalate anions comprising Nb or Ta into nanoscale reaction fields of porous ionic crystals

Polyoxometalates (POMs) are oxide cluster anions composed of high-valence early transition metals and widely used as catalysts. Yet base catalysis of POMs remains an ongoing challenge; group V (V, Nb,...

PSIII-38 Butyric acid and derivatives: In vitro anti-inflammatory effects tested in porcine alveolar macrophages

The aim of this experiment was to examine the anti-inflammatory effects of butyric acid, sodium butyrate, monobutyrin and tributyrin using porcine alveolar macrophages (PAMs). PAMs were isolated from the bronchial lavage of 6 piglets at 6 weeks of age, and then seeded at 106 cells/mL in 24-well plates. After 24 h incubation, cells were treated with different treatments in a randomized complete block design with 10 replicates. The treatments were in a factorial arrangement with 2 doses of lipopolysaccharide (LPS, 0 or 1 μg/mL) and 5 levels of organic acid (0, 0.5, 1, 2, 4 mM for butyric acid and tributyrin and 0, 1, 2, 4, 8 mM for sodium butyrate and monobutyrin). Supernatants were collected after another 24 h incubation and analyzed for tumor necrosis factor alpha (TNF-α). Cell viability was also tested by the MTT assay. Data were analyzed using the MIXED procedure of SAS. No cytotoxic effect was observed in LPS challenge and each organic acid with the percentage of live cells was more than 76% in comparison to the sham control. Sodium butyrate at 2 and 4 mM dose exhibited (P &lt; 0.01) a stimulatory effect on cell proliferation. LPS challenge remarkably stimulated (P &lt; 0.0001) TNF-α secretion from PAMs. In the non-challenge group, butyric acid, monobutyrin, and tributyrin linearly reduced TNF-α production from PAMs, whereas 2 mM sodium butyrate tended to increase (P = 0.056) TNF-α secretion from PAMs. In the LPS challenge group, all tested organic acid dose-dependently reduced (P &lt; 0.001) TNF-α production from LPS-challenged PAMs, with the strongest inhibiting effect observed at the highest dose. Results indicated that butyric acid and its derivatives that were tested in the current experiment all had strong anti-inflammatory activities in vitro.

125 Mint oils: in vitro anti-inflammatory effects tested in porcine alveolar macrophages

Essential oils as feed additives are being investigated for promoting health in piglets due to their anti-inflammatory activity. The objective of the study was to measure the in vitro anti-inflammatory effects of peppermint oil and spearmint oil with porcine alveolar macrophages as host immune responses. Briefly, macrophages were harvested from the bronchial lavage of 6 pigs at 6 weeks of age, and then seeded into 24-well plate with at 106 cells/mL. After 24 h incubation at 37oC and 5% CO2, cells were treated with mint oil or lipopolysaccharide (LPS) by randomized complete block design with 12 replicates. The treatments were 2 × 5 factorial arrangement with 2 doses of LPS (0 or 1 μg/mL) and 5 doses of mint oil (0, 25, 50, 100, 200 µg/mL). The supernatants were collected after another 24 h incubation to measure the concentration of tumor necrosis factor alpha (TNF-α) by ELISA assay. Cell viability was also tested by the MTT assay. Data were analyzed using the MIXED procedure of SAS 9.4. Administration of both mint oils and LPS did not impact the PAM cell viability of macrophages. LPS challenge significantly stimulated (P &lt; 0.05) TNF-α secretion from macrophages. In the non-challenge group, peppermint oil reduced (P &lt; 0.05) TNF-α production at 25, 50, and 100 μg/mL, whereas spearmint oil reduced (P &lt; 0.05) TNF-α concentration from 50 to 200 μg/mL. In the LPS challenge group, both mint oils linearly inhibited (P &lt; 0.001) TNF-α secretion from LPS-challenged macrophages with 200 μg/mL as the strongest dose. Results of the current study indicated that both peppermint and spearmint oils had anti-inflammatory activities in vitro. In vivo animal trials will be conducted to evaluate their impacts on animal health and performance.

Efficacy of Live Attenuated Vaccine and Commercially Available Lectin against Avian Pathogenic E. coli Infection in Broiler Chickens

In this study, the protective efficacy of an E. coli live attenuated vaccine was compared to the preventive administration of lectin preparation before the challenge. Two hundred broiler chicks were divided into eight equal groups. The first group was used as a negative control group. Three groups were vaccinated at day 1 with the avian colibacillosis live vaccine of which one group served as a vaccinated nonchallenged group. Another two groups were treated with lectin product (0.5 mL/L drinking water) for three days before the challenge. The last two groups served as challenge control for either E. coli O78 or O125 strains. The challenge was conducted at three weeks of age with either homologous O78 or heterologous O125 E. coli strains, using 0.5 mL/bird of each avian pathogenic E. coli (APEC) strain (~108 colony forming units “CFU”/mL)/subcutaneously. The bodyweight and feed conversion ratios (FCR) were calculated for four weeks. Clinical signs and gross and histopathological lesions were scored at two and seven days post inoculation (dpi). The heart and liver of euthanized chickens at 2 dpi were removed aseptically and homogenized to evaluate pathogenic E. coli colonization. Results showed that live avian colibacillosis vaccine reduced mortalities and APEC colonization in the homologous challenge group but not in the heterologous challenge group. Lectin-treated groups showed 20% and 16% mortality after challenge with E. coli O78 and O125, respectively, and both groups showed performance parameters, clinical signs, and histopathological lesion scores comparable to the negative control group, with variable E. coli colonization of heart and liver. The study demonstrated the efficacy of live attenuated avian colibacillosis vaccine against homologous but not heterologous APEC challenge in broiler chickens. The lectin-containing products can be used as a preventive medication to reduce the clinical impacts of colibacillosis regardless of the challenge strain. Standardization of the evaluation parameters for APEC vaccines is recommended.

Effect of Antimicrobial Peptide Microcin J25 on Growth Performance, Immune Regulation, and Intestinal Microbiota in Broiler Chickens Challenged with Escherichia coli and Salmonella

The purpose of this study was to investigate the effects of antimicrobial peptide microcin J25 (MccJ25) on growth performance, immune regulation, and intestinal microbiota in broilers. A total of 3120 one-day-old male Arbor Acres (AA) broilers were randomly allocated to five groups (12 replicates, 52 chickens per replicate). The treatments were control, challenge (0 mg/kg MccJ25), different dosages of antimicrobial peptide (AMP) (0.5 and 1mg/kg MccJ25), and antibiotic groups (20 mg/kg colistin sulfate). The MccJ25 groups increased the body weight gain (starter and overall) that was reduced in the challenge group. The overall (day 1 to day 42) feed-to-gain ratio (G:F) was significantly decreased in AMP groups compared with the challenge group. Birds fed AMP had a decreased population of total anaerobic bacteria (day 21 and day 42) and E. coli (day 21 and day 42) in feces, as well as a lower Salmonella infection rate (day 21 and day 42) compared with birds in the challenge group. The villus height of the duodenum, jejunum, and ileum, as well as the villus height/crypt depth of the duodenum and jejunum were greater in AMP groups than birds in the challenge group. Moreover, MccJ25 linearly improved the villus height of the duodenum and jejunum. The addition of MccJ25 decreased the concentration of TNF-α, IL-1β, and IL-6 compared with challenge group. At d 21, MccJ25 linearly reduced the level of IL-6. In conclusion, dietary supplemented MccJ25 effectively improved performance, systematic inflammation, and improved fecal microbiota composition of the broilers.

Effects of cLFchimera, a recombinant antimicrobial peptide, on intestinal morphology, microbiota, and gene expression of immune cells and tight junctions in broiler chickens challenged with C. perfringens

The current study was conducted to investigate the effects of cLFchimera, a recombinant antimicrobial peptide (AMP), on various productive performance and gut health attributes of broilers experimentally challenged with Clostridium perfringens (Cp). Three hundred and sixty 1-day-old chickens were randomly allocated to 4 treatments of 6 replicates as follows: T1) unchallenged group fed with corn-soybean meal (CSM) without Cp challenge and additives; T2) challenge group fed with CSM and challenged with Cp without any additives; T3) peptide group challenged with NE supplemented with 20 mg cLF36/kg diet (AMP); T4) antibiotic group challenged with NE and supplemented with 45 mg antibiotic (bacitracin methylene disalicylate)/kg diet (antibiotic). Birds had free access to feed and water, sampling for villi morphology and ileal microbiota were performed on days 10 and 22, while jejunal section was sampled for gene expression of cytokines, tight junctions proteins, and mucin only on day 22. Results showed that AMP ameliorated NE-related lesion in the jejunum and ileum and reduced mortality in challenged birds compared to challenge group with Cp without any additives. Also, supplementing challenged birds with AMP improved growth performance and reconstructed villi morphology. While antibiotic non-selectively reduced the count of bacteria, AMP positively restored ileal microflora in favor of good bacteria (i.e. Bifidobacteria spp. and Lactobacillus spp.). AMP beneficially regulated the expression of cytokines, junctional proteins, and mucin in the jejunum of challenged birds with Cp. Since cLFchimera ameliorated NE lesion score, reduced mortality, improved productive performance and gut health attributes in chickens compared to challenged group and also were mostly similar with those of antibiotics and therefore, it could be concluded that this chimeric peptide can be a worthy candidate to substitute growth promoter antibiotics, while more research is required to unveil the exact mode of action of this synthetic peptide.Author summaryNecrotic enteritis (NE) is a detrimental enteric disease in the poultry industry worldwide. The etiological factor of this disease is Clostridium perfringens, which is gram-positive anaerobic bacterium. This bacterium is common inhabitant of the intestine in lower counts (105), but it becomes pathogenic in higher counts and can secrete NetB toxin, which is the main cause of inducing NE in broilers. Due to the emergence of antibiotic-resistant bacteria, new generation of antimicrobial additives such as antimicrobial peptides (AMPs) has been introduced to the poultry industry. AMPs are small molecules with 12-50 amino acids having antibacterial activity. Recently, we extracted new AMP from camel milk, expressed in E. coli, refined and lyophilized to produce purified peptides. The current study investigated the effects of this peptide on prevention of NE in broilers. Results showed that AMP ameliorated lesion scores in the intestine and reduced mortality in challenged birds. AMP improved growth performance and reconstructed villi morphology in NE-challenged broilers. While antibiotic non-selectively reduced the count of bacteria, AMP positively restored ileal microflora. AMP beneficially regulated the expression of cytokines, junctional proteins, and mucin in the jejunum of NE-challenged birds.

Lactobacillus fermentum UCO-979C strongly inhibited Helicobacter pylori SS1 in Meriones unguiculatus

Searching for bacterial probiotics active upon Helicobacter pylori continue to be an important clinical challenge because of the increased prevalence of this highly priority pathogen in humans. In this work, we assess the in vivo anti-H. pylori SS1 (cagA+/vacAs2m2+) properties of a previously isolated human gastric probiotic strain Lactobacillus fermentum UCO-979C by using a Meriones unguiculatus (Mongolian gerbil) model. Animals were administered with a saline suspension of L. fermentum UCO-979C or H. pylori SS1 as negative and positive control for H. pylori colonisation controls, prior to assayed the challenge group that was administered with these two species per animal for detecting protective activity of the probiotic strain against colonisation. The results showed that L. fermentum UCO-979C strongly inhibited the colonisation of H. pylori decreasing up to 87% of the colonisation in the antrum by the pathogen, suggesting that this probiotic strain has a strong probiotic activity against H. pylori in the most valuable animal model for in vivo assays nowadays.

Assessment of 30/20-Microgram Disk Content versus MIC Results for Ceftazidime-Avibactam Tested against Enterobacteriaceae and Pseudomonas aeruginosa

ABSTRACT We evaluated the correlation between MIC and disk diffusion inhibition zones when testing ceftazidime-avibactam, using the 30/20-μg disk and the disk diffusion and MIC breakpoints established by the U.S. FDA and the Clinical and Laboratory Standards Institute (CLSI). Organisms used included 2 groups of Enterobacteriaceae isolates and 2 groups of Pseudomonas aeruginosa isolates; 1 group of each consisted of randomly selected isolates and the second group consisted of a challenge group from thousands of surveillance isolates with an increased proportion of organisms displaying ceftazidime-avibactam MIC values close to the breakpoints. Broth microdilution, disk diffusion tests, and data analysis were performed according to reference standardized methods. Ceftazidime-avibactam breakpoints of ≤8/4 (susceptible) and ≥16/4 μg/ml (resistant) for MIC and ≥21/≤20 mm for disk diffusion, as established by the U.S. FDA and the CLSI, were applied for Enterobacteriaceae and P. aeruginosa . Ceftazidime-avibactam MIC and disk zone (30/20-μg disk) correlation were acceptable when testing Enterobacteriaceae (overall, very major [VM] and major [Ma] error rates of 0.4% and 0.0%, respectively) and nearly so when testing P. aeruginosa (2.3% VM and 2.9% Ma errors). In summary, disk diffusion and broth microdilution testing results demonstrated good categorical agreement for ceftazidime-avibactam against Enterobacteriaceae and P. aeruginosa , using 30/20-μg disks.