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Spoiled silages can harbor pathogenic and antimicrobial-resistant microbes. The potential of some antimicrobial additives to inhibit certain pathogenic and antimicrobial-resistant bacteria in air-exposed silage was measured using pure and mixed bacterial cultures. With pure cultures, laurate and monolaurin (5 mg·mL−1) caused decreases (P 7 log10 colony-forming units (CFU)·mL−1 in Listeria monocytogenes and Enterococcus faecalis compared to controls. Ten-fold higher amounts of these inhibitors were needed to equivalently decrease staphylococci. 2-Nitropropanol (1 mg·mL−1) decreased (P 10 CFU·mL−1 after 6 and 24 h incubations, respectively. In air-exposed whole-plant corn silage the inhibitors caused decreases, although not necessarily significant, of 0.7–2.2 log10 CFU·mL−1 in L. monocytogenes, staphylococci and culturable aerobes after 24 h incubation, with modest yet significant (P 10 CFU·mL−1) of yeasts and molds. Tests for carry-over effects against ruminal microbes revealed laurate, monolaurin, and 2-nitropropanol inhibited methanogenesis by >50% (P

Tilapia is one of the most extensively farmed fish on a global scale. Lately, many studies have been carried out to select and produce probiotics for cultured fish. Bacteria from the genera Bacillus, Lactiplantibacillus (synonym: Lactobacillus), and Lactococcus are the most widely studied with respect to their probiotic potential. Among these microorganisms, Lactococcus lactis has outstanding prospects as a probiotic because it is generally recognized as safe (GRAS) and has previously been shown to exert its probiotic potential in aquaculture through different mechanisms, such as competitively excluding pathogenic bacteria, increasing food nutritional value, and enhancing the host immune response against pathogenic microorganisms. However, it is not sufficient to simply select a microorganism with significant probiotic potential for commercial probiotic development. There are additional challenges related to strategies involving the mass production of bacterial cultures, including the selection of production variables that positively influence microorganism metabolism. Over the last ten years, L. lactis production in batch and fed-batch processes has been studied to evaluate the effects of culture temperature and pH on bacterial growth. However, to gain a deeper understanding of the production processes, the effect of hydrodynamic stress on cells in bioreactor production and its influence on the probiotic potential post-manufacturing also need to be determined. This review explores the trends in tilapia culture, the probiotic mechanisms employed by L. lactis in aquaculture, and the essential parameters for the optimal scale-up of this probiotic.

The addition prebiotics in broiler diets can benefit digestion and nutrient abortion. The objective of the present study was to evaluate the effects of moringa leaf powder and agave inulin on growth performance, intestinal morphology, and slaughter traits of broiler chickens over 40 d of grow-out. A total of 280 broilers (Ross 308) aged 1 d were randomly allocated to 4 treatments, with 7 replicates each and 10 chicks per replicate: T1 = control diet, T2 = control diet with 15 g/kg of moringa leaf powder, T3 = control diet with 15 g/kg of agave inulin, and T4 = control diet with 15 g/kg of moringa leaf powder and 15 g/kg of agave inulin. The results showed that analysis of treatments at time were not different (P > 0.05) for broiler weights, feed and water intake, and weight gain. Treatment was significant (P

Probiotic products are viewed as an alternative to the use of antibiotics in freshwater fishes farming. Probiotic organisms include bacteria, yeast, and filamentous fungi offering different benefits to fish including growth promotion, inhibition of pathogen colonisation, and improvement of nutrient digestion, water quality, and stress tolerance, as well as enhancement of reproduction. For these reasons, this review aims to identify the main trends in probiotic amendment in freshwater fishes. Strategies to incorporate the probiotic strains in the fish feed or pellets to allow optimal viability of the strains as they reach the fish gastrointestinal tract (GIT) are crucial in probiotic research and commercial applications for freshwater fish.

We tested the effects of Galena or Chinook hops treatment (6% wt/wt) of simulated composts (13 d) of wood chip litter (WCL) alone or mixed 3:1 with ground Bluestem hay (BSH). Results revealed that net losses of urea and ammonia in the WCL litter composted without BSH (n = 3/treatment) were unaffected by hops treatment (P = 0.37 and 0.13, respectively), averaging 0.32 ± 0.7 and 0.03 ± 1.5 µmol/g, respectively). The loss of uric acid was 60% less (P = 0.04) in the Galena hops-treated WCL compost than in the negative control compost (13.9 ± 3.8 vs 24.4 ± 5.6 µmol/g, respectively) and intermediate in the Chinook-treated compost (16.0 ± 2.7 µmol/g). Nitrogen losses during compost of WCL: BSH (n = 2/treatment) were unaffected by hops treatment (P = 0.77, 0.73 and 0.14 for uric acid, urea and ammonia, respectively), averaging 12.21 ± 3.1, 0.64 ± 0.6 and 1.07 ± 0.1 µmol/g, respectively, respectively). Assessment of potential carry over effects of residual hops in the composts during in vitro rumen fermentation (0.2 g of treated and control compost, in triplicate, mixed with 10 mL freshly collected rumen fluid) for 24 h at 39oC under 100% CO2 revealed no effects of hops treatment on H2 accumulations in incubations with WCL or WCL: BSH composts (P = 0.22 and 0.17, respectively), averaging 0.23 ± 0.1 and 0.17 ± 0.1 µmol/mL fluid, respectively. Accumulations of CH4 in rumen incubations of WCL composts were unaffected by hops treatment (P = 0.24), averaging 15.07 ± 2.0 µmol/mL, but were increased (P = 0.0002) in incubations of WCL: BSH composts, averaging 14.1 ± 0.4 and 13. 8 ± 0.6 µmol/mL in Galena- and Chinook-treated compost compared with 11.2 ± 0.4 µmol/mL in control incubations. Results indicate hops treatment may lessen uric acid degradation composting poultry litter without inhibiting rumen fermentation.

Staphylococcus aureus (S. aureus) causes gastrointestinal illness worldwide. Disinfectants are used throughout the food chain for pathogenic bacteria control. We investigated S. aureus bioavailability in swine Mandibular lymph node tissue (MLT) and pork sausage meat (PSM), established susceptibility values for S. aureus to disinfectants, and determined the multilocus sequence type of MRSA strains. Antimicrobial and disinfectant susceptibility profiles were determined for 164 S. aureus strains isolated from swine feces (n = 63), MLT (n = 49) and PSM (n = 52). No antimicrobial resistance (AMR) was detected to daptomycin, nitrofurantoin, linezolid, and tigecycline, while high AMR prevalence was determined to erythromycin (50.6%), tylosin tartrate (42.7%), penicillin (72%), and tetracycline (68.9%). Methicillin-resistant S. aureus (MRSA) strains, ST398 (n = 6) and ST5 (n = 1), were found in the MLT and PSM, 4 MRSA in MLT and 3 MRSA strains in the PSM. About 17.5% of feces strains and 41.6% of MLT and PSM strains were resistant to chlorhexidine. All strains were susceptible to triclosan and benzalkonium chloride, with no cross-resistance between antimicrobials and disinfectants. Six MRSA strains had elevated susceptibilities to 18 disinfectants. The use of formaldehyde and tris(hydroxylmethyl)nitromethane in DC&R was not effective, which can add chemicals to the environment. Didecyldimethylammonium chloride and benzyldimethylhexadecylammonium chloride were equally effective disinfectants. ST398 and ST5 MRSA strains had elevated susceptibilities to 75% of the disinfectants tested. This study establishes susceptibility values for S. aureus strains from swine feces, mandibular lymph node tissue, and commercial pork sausage against 24 disinfectants. Since it was demonstrated that S. aureus and MRSA strains can be found deep within swine lymph node tissue, it may be beneficial for the consumer if raw swine lymph node tissue is not used in uncooked food products and pork sausage.

Raramuri Criollo cattle from the Chihuahuan desert in northern Mexico have been described as an ecological ecotype due to their enormous advantage in land grass utilization and their capacity to diversify their diet with cacti, forbs and woody plants. This diversification in diet utilization, could reflect upon their microbiome composition. The aim of this study was to characterize the rumen microbiome of Raramuri criollo cattle and to compare it to other lineages that graze in the same area. A total of 28 cows representing three linages [Criollo (n = 13), European (n = 9) and Criollo x European Crossbred (n = 6)] were grazed without supplementation for 45 days. DNA was extracted from ruminal samples and the V4 region of the 16S rRNA gene was sequenced on an Illumina platform. Data were analyzed with the QIIME2 software package and DADA2 plugin and the amplicon sequence variants were taxonomically classified with naïve Bayesian using the SILVA 16S rRNA gene reference database (version 132). Statistical analysis was performed by ANOVA and PERMANOVA for alpha and beta diversity indexes, respectively, and the non-strict version of linear discriminant analysis effect size (LEfSe) was used to determine significantly different taxa among lineages. Differences in beta diversity indexes (P < 0.05) were found in ruminal microbiome composition between Criollo and European groups, whereas the Crossbred showed intermediate values when compared to the pure breeds (Table 1). LEfSe analysis identified a total of 20 bacterial groups that explained differences between lineages, including one for Crossbreed, ten for European and nine for Criollo. These results show ruminal microbiome differences between Raramuri criollo cattle and the mainstream European breeds used in the northern Mexico Chihuahuan desert and reflect that those differences could be a consequence of dissimilar grazing behavior.

Strategies are sought to reduce the carriage and dissemination of zoonotic pathogens and antimicrobial-resistant microbes within food-producing animals and their production environment. Thymol (an essential oil) is a potent bactericide in vitro but in vivo efficacy has been inconsistent, largely due to its lipophilicity and absorption, which limits its passage and subsequent availability in the distal gastrointestinal tract. Conjugation of thymol to glucose to form thymol-β-d-glucopyranoside can decrease its absorption, but in vivo passage of effective concentrations to the lower gut remains suboptimal. Considering that contemporary swine diets often contain 5% or more added fat (to increase caloric density and reduce dustiness), we hypothesized that there may be sufficient residual fat in the distal intestinal tract to sequester free or conjugated thymol, thereby limiting the availability and subsequent effectiveness of this biocide. In support of this hypothesis, the anti-Salmonella Typhimurium effects of 6 mM free or conjugated thymol, expressed as log10-fold reductions of colony-forming units (CFU) ml−1, were diminished 90 and 58%, respectively, following 24-h in vitro anaerobic fecal incubation (at 39°C) with 3% added vegetable oil compared to reductions achieved during culture without added oil (6.1 log10 CFU ml−1). The antagonistic effect of vegetable oil and the bactericidal effect of free and conjugated thymol against Escherichia coli K88 tested similarly were diminished 86 and 84%, respectively, compared to reductions achieved in cultures incubated without added vegetable oil (5.7 log10 CFU ml−1). Inclusion of taurine (8 mg/ml), bile acids (0.6 mg/ml), or emulsifiers such as polyoxyethylene-40 stearate (0.2%), Tween 20, or Tween 80 (each at 1%) in the in vitro incubations had little effect on vegetable oil-caused inhibition of free or conjugated thymol. Based on these results, it seems reasonable to suspect that undigested lipid in the distal gut may limit the effectiveness of free or conjugated thymol. Accordingly, additional research is warranted to learn how to overcome obstacles diminishing bactericidal activity of free and conjugated thymol in the lower gastrointestinal tract of food-producing animals.

The aim of this study was to compare two Mexican chorizo formulations (treatments) considering physicochemical, microbiological and sensorial attributes over 14 days in refrigeration. One formulation involved vinegar (T1= control chorizo + 2.4 % vinegar) and the other oregano essential oil (OEO; Lippia berlandieri Schauer) (T2= chorizo + 2.4 % OEO) as a substitute for vinegar. Both formulations were evaluated using a completely randomized experimental design. The effect of the interaction between treatments (Ƭi) and days (δj) on pH, Hue and Chroma was highly significant ((Ƭδ)ij; P < 0.001). T1 pH values were lower than those for T2 at 1, 7 and 14 d. Redness (a*) and total color change (TC∆) values were different between treatments (Ƭi; P < 0.05), being higher in T1 than in T2 at 14 d. These results indicate that OEO as a substitute for vinegar reduces Hue and increases Chroma of the typical red color of Mexican chorizo. In general, OEO improved the preference for oregano aroma without changing overall acceptance. OEO represents an interesting alternative as a substitute for vinegar in Mexican chorizo formulation.

The present study investigated the effects of short-chain fructooligosaccharides (FOS) as dietary supplements on stress, immune response, gut microbiota, growth, and survivability of three different treatment groups of Pacific white shrimp, Litopaneous vennamei, cultured in a recirculating system. The experiment was conducted over a 35-day trial period. Shrimps were fed diets, 15 times a day using automated feeder, supplemented with GOS at 0%, 0.15%, and 0.30% by weight. Denaturing gradient gel electrophoresis analysis revealed that the enteric microbial community of shrimp fed the basal diet differed markedly ( 0.05), probably due to the limited length of the feeding trial.

Staphylococci are important mastitic-pathogens of humans and livestock. Chlorate is reported to be a potent inhibitor against staphylococci but adaptation by the microbes can occur. Presently, we cultured multi-drug resistant Staphylococcus aureus strain ATCC 12600 anaerobically at 39oC in nitrate-supplemented (5 mM) Tryptic Soy broth. The broth was treated without (control) or alone with 5 mM sodium chlorate (ClO3) or 9 mM of either 2-nitro-1-propanol (NPOH), ethyl nitroacetate (ENA) or ethyl 2-nitropropionate (E2NPA) or with combinations of CLO3 and respective nitrocompound. Control and treated cultures were incubated in triplicate and growth was measured via absorbance (600 nm) at during 9 h. An analysis of variance revealed an inhibitory effect of treatments (P < 0.05; SEM = 0.078) on mean specific growth rates of S. aureus, with rates during logarithmic growth being most rapid in controls and cultures treated with ENA or EN2PA (1.45, 1.23 and 1.21 h-1, respectively) and more than 92% slower in NPOH and NPOH+CLO3-treated cultures (0.09 and 0.03 h-1, respectively). Growth rates of cultures treated solely with CLO3 (0.66 h-1) were more than 50% slower than controls and were decreased further in cultures treated with combinations of CLO3 plus E2NPA or ENA (0.39 and 0.45 h-1). After 9 h of growth, maximum optical densities (maxOD) were highest for controls and cultures treated with ENA or EN2PA (0.52, 0.52 and 0.50 maxOD, respectively), intermediate in cultures treated with CLO3 alone (0.21 maxOD) and lower yet in cultures treated with CLO3 plus ENA, E2NPA or NPOH (0.15, 0.11 and 0.02 maxOD, respectively). The maxOD for cultures treated with NPOH alone was 0.02 and did not differ from cultures treated with the combination of CLO3+NPOH. Results demonstrate marked synergistic and prolonging effects of combing ENA and E2NPA with CLO3 but no additional effect of the potent anti-staphylococcal activity of NPOH.

The gut of food-producing animals is a reservoir for foodborne pathogens. Thymol is bactericidal against foodborne pathogens but rapid absorption of thymol from the proximal gut precludes the delivery of effective concentrations to the lower gut where pathogens mainly colonize. Thymol-β-d-glucopyranoside is reported to be more resistant to absorption than thymol in everted jejunal segments and could potentially function as a prebiotic by resisting degradation and absorption in the proximal gut but being hydrolysable by microbial β-glycosidase in the distal gut. Previous in vitro studies showed bactericidal effects of thymol-β-d-glucopyranoside against Campylobacter, Escherichia coli, and Salmonella enterica serovar Typhimurium in the presence but not absence of intestinal microbes expressing β-glycosidase activity, indicating that hydrolysis was required to obtain antimicrobial activity. Presently, the oral administration of thymol-β-d-glucopyranoside was studied to examine the effects on intestinal carriage of Campylobacter, E. coli, and S. Typhimurium in swine. The effects of thymol-β-d-glucopyranoside or thymol on antimicrobial sensitivity of representative E. coli isolates and characterized Salmonella strains were also explored. Results from two in vivo studies revealed little antimicrobial effects of thymol-β-d-glucopyranoside on Campylobacter, E. coli, or S. Typhimurium in swine gut. These findings add credence to current thinking that hydrolysis and absorption of thymol-β-d-glucopyranoside and thymol may be sufficiently rapid within the proximal gut to preclude delivery to the distal gut. Antibiotic susceptibilities of selected bacterial isolates and strains were mainly unaffected by thymol. Further research is warranted to overcome obstacles, preventing the delivery of efficacious amounts of thymol-β-d-glucopyranoside to the lower gut.

Medium chain fatty acid (MCFA) treatment of aerobically exposed silage during feed-out is a potential strategy to prevent growth of spoilage and pathogenic microbes. To evaluate the effects of feeding MCFA-treated silage on the rumen fermentability, we incubated 0.02 g of overnight air-exposed corn silage that had been treated individually without or with (0.75% wt/wt) C6, C8, C10 or C12 or with equal proportion mixtures of C6:C8:C10:C12 or C8:C10 with 10 mL freshly collected ruminal fluid. Additions were made while flushing with CO2 and tubes (3 tubes/treatment) were then capped and sealed. After 24 h incubation at 39oC, headspace gases and fluid volatile fatty acids were measure using gas chromatography techniques. Results from a completely randomized analysis of variance revealed higher hydrogen accumulations (P < 0.05) only in incubations containing silage treated with the C8:C10 MCFA mixture when compared to controls, with mean ± SD concentrations (µmol/mL incubation fluid) being 2.19 ± 1.6 versus 0.08 ± 0.04, respectively. Treatment effects were not observed (P > 0.05) on accumulations (µmol/mL) of methane (13.25 ± 2.5), acetate (19.66 ± 5.6), propionate (7.27 ± 2.0), butyrate (12.36 ± 2.7) or stochiometric estimates of amounts of hexose fermented (41.39 ± 9.7), although the acetate:propionate ratios of incubations of silage treated with C8 or the C8:C10 mixture were higher (P < 0.05) than those of untreated controls (3.46 ± 0.7, 3.46 ± 0.5 and 2.35 ± 0.1, respectively). Consequently, correspondingly estimates of fermentation efficiency, calculated based caloric energy values of amounts of acetate, propionate and butyrate relative to glucose, were slightly lower (P < 0.05) for the incubations of silage treated with C8 and the C8:C10 mix compared to controls (74.36 ± 1.1, 74.82 ± 0.2 and 76.55 ± 0.3 %, respectively). Results reveal little negative effect of MCFA treatment on ruminal fermentability of silage.

Introduction: Current diets of broiler chickens tend to increase protein levels to obtain high productive variables that are achieved in combination with genetic, management, and sanitary improvements, among others. An increase in dietary crude protein levels does not always accompany an increase in broiler productive efficiency due to multiple factors involved in the production system. The objective of this study was to evaluate the effect of increasing levels of dietary crude protein (CP) on productive performance, carcass characteristics, and chemical composition of breast and thigh meat in broiler chickens raised in the dry subtropics of northeastern Mexico.Method: The study used 200, 1-day-old male Ross broiler chicks. In a completely randomized design, birds were allocated to the four treatments with five replicates (floor pens) of ten birds each. The trial was divided in two phases (starter and finisher) of 21 days each (42 days total). Treatment diets (T) for starter and finisher phases had crude protein concentrations (CP; %) of 21 and 18.1 (T1), 21.4 and 18.5 (T2), 21.8 and 18.9 (T3), and 22.2 and 19.3 (T4), respectively. Within each feeding phase, the four treatment diets were formulated to similar levels of apparent metabolizable energy.Results: Protein concentrations had no effect (P > 0.05) on weight gain, while feed intake was greater in T1 (P < 0.05) than in T2 and T3. Feed conversion was better in T2 and T4 (P < 0.05) than in T1. There was no influence of treatment on carcass weight or carcass cuts (P > 0.05). Carcass yield was greater in T1 than in T3 (P < 0.05). Breast and thigh dry matter and ether extracts were similar (P > 0.05) between treatments. Breast crude protein was greater (P < 0.05) in T2 than in T3. The lowest (P < 0.05) CP concentration in thigh meat was in T3.Discussion or Conclusion: These results indicated that in the dry subtropics area of northeastern Mexico increases in CP above the level of T2 (21.4% and 18.5% CP in starter and finisher diets, respectively) did not improve broiler chicken productive performance, carcass characteristics or meat chemical composition.

Numerous Salmonella enterica serovars can cause disease and contamination of animal-produced foods. Oligosaccharide-rich products capable of blocking pathogen adherence to intestinal mucosa are attractive alternatives to antibiotics as these have potential to prevent enteric infections. Presently, a wood-derived prebiotic composed mainly of glucose-galactose-mannose-xylose oligomers was found to inhibit mannose-sensitive binding of select Salmonella Typhimurium and Escherichia coli strains when reacted with Saccharomyces boulardii. Tests for the ability of the prebiotic to prevent binding of a green fluorescent protein (GFP)-labeled S. Typhimurium to intestinal porcine epithelial cells (IPEC-J2) cultured in vitro revealed that prebiotic-exposed GFP-labeled S. Typhimurium bound > 30% fewer individual IPEC-J2 cells than did GFP-labeled S. Typhimurium having no prebiotic exposure. Quantitatively, 90% fewer prebiotic-exposed GFP-labeled S. Typhimurium cells were bound per individual IPEC-J2 cell compared to non-prebiotic exposed GFP-labeled S. Typhimurium. Comparison of invasiveness of S. Typhimurium DT104 against IPEC-J2 cells revealed greater than a 90% decrease in intracellular recovery of prebiotic-exposed S. Typhimurium DT104 compared to non-exposed controls (averaging 4.4 ± 0.2 log10 CFU/well). These results suggest compounds within the wood-derived prebiotic bound to E. coli and S. Typhimurium-produced adhesions and in the case of S. Typhimurium, this adhesion-binding activity inhibited the binding and invasion of IPEC-J2 cells.

Poultry litter is a potentially valuable crude protein feedstuff for ruminants but must be treated to kill pathogens before being fed. Composting kills pathogens but risks losses of nitrogen due to volatilization or leaching as ammonia. Treatment of poultry litter with ethyl nitroacetate, 3-nitro-1-propionate, ethyl 2-nitropropionate (at 27 µmol/g), decreased numbers of experimentally-inoculated Salmonella Typhimurium (>1.0 log10 compared to controls, 4.2 ± 0.2 log10 CFU/g) but not endogenous Escherichia coli early during simulated composting. By day 9 of simulated composting, Salmonella and E. coli were decreased to non-detectable levels regardless of treatment. Some nitro-treatments preserved uric acid and prevented ammonia accumulation, with 18% more uric acid remaining and 17–24% less ammonia accumulating in some nitro-treated litter than in untreated litter (18.1 ± 3.8 µmol/g and 3.4 ± 1.4 µmol/g, respectively). Results indicate that nitro-treatment may help preserve uric acid in composted litter while aiding Salmonella control.

The influence of sodium chlorate (SC), ferulic acid (FA), and essential oils (EO) was examined on the survivability of two porcine diarrhetic enterotoxigenic Escherichia coli (ETEC) strains (F18 and K88) and populations of porcine fecal bacteria. Fecal bacterial populations were examined by denaturing gradient gel electrophoresis (DGGE) and identification by 16S gene sequencing. The treatments were control (no additives), 10 mM SC, 2.5 mg FA /mL, a 1.5% vol/vol solution of an EO mixture as well as mixtures of EO + SC, EO + FA, and FA + SC at each of the aforementioned concentrations. EO were a commercial blend of oregano oil and cinnamon oil with water and citric acid. Freshly collected porcine feces in half-strength Mueller Hinton broth was inoculated with E. coli F18 (Trial 1) or E. coli K88 (Trial 2). The fecal-E. coli suspensions were transferred to crimp top tubes preloaded with the treatment compounds. Quantitative enumeration was at 0, 6, and 24 h. All treatments reduced (P < 0.05) the counts of E. coli F18 at 6 and 24 h. With the exception of similarity coefficient (%SC), all the other treatments reduced (P < 0.05) the K88 counts at 24 h. The most effective treatments to reduce the F18 and K88 CFU numbers were those containing EO. Results of DGGE revealed that Dice percentage similarity coefficients (%SC) of bacterial profiles among treatment groups varied from 81.3% to 100%SC. The results of gene sequencing showed that, except for SC at 24 h, all the other treatments reduced the counts of the family Enterobacteriaceae, while Lactobacillaceae and Ruminococcaceae increased and Clostridiaceae decreased in all treatments. In conclusion, all treatments were effective in reducing the ETEC, but EO mixture was the most effective. The porcine microbial communities may be influenced by the studied treatments.

To study the antimicrobial and uric acid-preserving activity of pine bark tannin on poultry litter composting, antibiotic-free wood chip-based poultry litter was distributed (11 g) to 50-mL conical centrifuge tubes and immediately amended with 1.3 mL0.4 M sodium phosphate buffer (control) or with 1.3 mL condensed tannins from pine bark (Pinus palustris; 9 % tannin wt/vol in water). All tubes (n = 3 tubes/treatment) were inoculated with a novobiocin and naladixic acid-resistant Salmo-nella typhimurium (STNN) to achieve 3.0 log10 CFU/g and incubated at 37oC for 3 days to simulate an initial compost period. Wildtype E. coli and the challenge STNN strain as well as concentrations of ammonia, uric acid and urea were measured on days 0 and 3. Pine bark tannin treatment decreased (p0.05). Ammonia accumulation decreased (p0.05). Results suggest that pine bark tannin treatment may preserve uric acid and reduce ammonia volatilization in composted litter while aiding Salmonella control.

Algamune™ is a commercial additive produced from Euglena gracilis, providing a rich source of the β-1,3-glucan paramylon. Isolated kidney phagocytes of Nile tilapia were incubated with graded doses (0, 8, 16, 32, 64 and 128 μg/ml) of Algamune™ and purified paramylon to gauge their ability to elicit the production of reactive oxygen species. A linear response was observed for extracellular superoxide anion for both sources but only Algamune™ for intracellular superoxide anion. After corroborating the immunostimulant properties ex vivo, a feeding trial was conducted to evaluate the dietary supplementation of Algamune™ (0, 100, 200, 400 and 800 mg/kg of diet) for Nile tilapia. Fish were fed for 3 weeks, after which, fish were sampled for blood and head kidney phagocytes. The remaining fish were challenged with Streptococcus iniae. Macrophage extracellular superoxide anion production was significantly elevated in fish fed diets with 200 mg of Algamune™ kg-1 when compared to fish fed the basal diet. Even though the disease challenge did not show statistical differences, it is worth mentioning that fish fed intermediate doses of Algamune™ had lowest numerical mortality values. Therefore, Algamune™ was demonstrated to enhance some immunological responses of tilapia both in ex vivo and in vivo.

To reduce susceptibility to stressors and diseases, immune-modulators such as β-glucans have been proven effective tools to enhance the innate immune responses of fish. Consequently, commercial sources of this polysaccharide are becoming increasingly more available. Algamune™ is a commercial additive produced from Euglena gracilis, as a source of linear β-1,3-glucan. In order to evaluate the immunomodulatory effects of this β-glucan product, the present study assessed the innate immune parameters of red drum (Sciaenops ocellatus) exposed to Algamune™ ex vivo and in vivo. Isolated kidney phagocytes were incubated with graded concentrations (0, 0.2, 0.4, 0.8, 1.6 and 3.2 mg L−1) of dried Euglena gracilis (Algamune™) as well as purified Paramylon (linear β-1,3 glucan). Increased bactericidal activity against Streptococcus iniae, and production of intracellular O2− anion superoxide were stimulated by both β-glucan sources. A reduced activity of extracellular anion superoxide was observed by the phagocytes incubated with Algamune ™. After corroborating the effectiveness of the glucan source ex vivo, a feeding trial was conducted using red drum juveniles (∼26.6 g initial weight). Fish were fed diets with graded levels of Algamune™ (0, 100, 200, 400 and 800 mg kg−1) twice daily for 21 days. No significant differences were detected regarding production performance parameters. At the end of the feeding trial, blood, intestinal content, and kidney were sampled. Intestinal microbiota from fecal material was analyzed through denaturing gradient gel electrophoresis (DGGE) and found to be similar among all treatments. No significant differences were detected for oxidative radical production from whole blood, and isolated phagocytes, and plasma lysozyme activity. However, the total hemolytic activity of red drum plasma was increased in fish fed 100 and 200 mg kg−1 of dietary Algamune™ when compared to fish fed the basal diet. Based on results from both ex vivo and in vivo trials, β-glucan from Algamune™ was demonstrated to have a moderate immunostimulatory effects on red drum.

The aim of this study was to evaluate the effect of oregano essential oil (MOO) from Mexican oregano, Lippia berlandieri Schauer, as substitute for Mexican oregano powder (MOP) on pork chorizo physicochemical characteristics, texture, antioxidant capacity, aerobic bacteria colony counts, and sensory evaluation under storage conditions over 7 d. The treatments were T1 = chorizo + 0.1% MOP and T2 = chorizo + 0.1% MOO. The pH, redness (a*), yellowness (b*), Chroma, and browning index (BI) were affected by treatments and storage time. T2 presented lower pH (5.27) at d 1 than at d 7 (5.34), as well as a* (23.13 vs. 25.27), b* (14.85 vs. 17.45), Chroma (28.60 vs. 30.79), and BI (103.42 vs. 109.82) were higher at d 7. At d 1, hardness (1392.75 vs. 872.29 g), springiness (0.3675 vs. 0.3351 mm), gumminess (491.45 vs. 284.38 g), and chewiness (180.25 vs. 95.43 g mm) were higher in T1 than T2. Aerobic bacteria counts (T1—4.19 vs. 4.73 log CFU/g and T2—4.37 vs. 4.50 log CFU/g, respectively) increased within each treatment at d 7. Antioxidant capacity was not affected (26.48 and 27.42%). Oregano odor was different at 7 d with T2 having a stronger odor (5.70) than T1 with oregano powder (4.63). Mexican oregano essential oil in the pork chorizo formulation improved pH, color parameters, textural profile, and sensory characteristics. KEYWORDS antioxidant, color, essential oil, Mexican oregano, microbiology, oregano powder, pH, sausage, sensory, sensory evaluation, textural profile

The aim of this study was to investigate levels of inulin and pectin replacing pork back fat in meat batter (MB) formulation. Six treatments were evaluated: T1, control MB (100% pork back fat); T2, MB + 70% pork back fat (low fat); T3, MB + 85% pork back fat + 15% inulin; T4, MB + 70% pork back fat + 30% inulin; T5, MB + 85% pork back fat + 7.5% inulin + 7.5% pectin; and T6, MB + 70% pork back fat + 15% inulin + 15% pectin. T6 reduced pH, maintained brightness (L*), increased redness (a*), yellowness (b*), Chroma, and browning index (BI); T4 decreased a*, b*, BI, and water holding capacity but increased the total color change (∆E), cooking loss, and total expressible fluid. The addition of 15% inulin and 15% pectin can be used to replace fat without affecting the physical properties of MB.

Broiler chickens may serve as reservoirs for human colonization by vancomycin-resistant Enterococcus (VRE). We examined the effects of vancomycin and two commonly used antimicrobial feed additives on VRE colonization in broiler chickens during grow-out. Chicks received unsupplemented feed or feed containing vancomycin, chlortetracycline, or tylosin from day of hatch to grow-out at 6 weeks. At 3 days of age, chicks received by crop gavage 107 colony-forming units (CFUs) of a human or poultry VRE isolate. Cecal contents were monitored weekly for VRE, short-chain fatty acids (SCFAs), and bacterial denaturing gradient gel electrophoresis (DGGE) profile methods. Vancomycin promoted persistent and high-level colonization with human- and poultry-derived VRE to grow-out in comparison with controls, while treatment with chlortetracycline and tylosin did not. Colonization by the poultry isolate in control, chlortetracycline, and tylosin groups persisted throughout the grow-out period with low concentration...