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1.
J Food Prot ; 86(10): 100139, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37567500

RESUMO

In recent years, there has been an increased interest in beef cattle shedding of foodborne pathogens due to the potential to contaminate surrounding food crops; however, the number of studies published on this topic has declined as the majority of research has emphasized on postharvest mitigation efforts. A field study was conducted to determine the prevalence of pathogens and indicator bacteria in beef cattle fed two different direct-fed microbials (DFMs). Fecal samples from a total of 3,708 crossbred yearling cattle randomly assigned to 16 pens and two treatment groups at a commercial cattle feedlot were taken. During the study period, diets were supplemented with two different DFMs i.) Lactobacillus acidophilus (NP51) and Propionibacterium freudenreichii (NP24) (9 log10CFU/head/day), and ii.) Lactobacillus salivarius (L28) (6 log10CFU/head/day). Fecal samples from pen floors were collected on days 0, 21, 42, 63, 103, and analyzed for the presence of Salmonella and E. coli O157:H7 and concentration of E. coli O157:H7, Enterobacteriaceae, and C. perfringens. Fecal samples collected from cattle fed L28 had significantly lower concentration of C. perfringens (p < 0.05) and had a similar prevalence with no significant differences in E. coli O157:H7 as those fed NP51/NP24 through the study until day 103. On day 103, the prevalence in cattle fed L28 was 40% with a concentration of 0.95 log10MPN/g while those fed NP51/NP24 were 65% with a concentration of 1.2 log10MPN/g. Cattle supplemented with NP51/NP24 achieved a significant log reduction of EB by 2.4 log10CFU/g over the course of the 103-day supplementation period compared to L28. Salmonella prevalence was also measured, but not detected in any samples at significant amounts to draw conclusions. It is evident that E. coli O157:H7 and other foodborne pathogens are still prevalent in cattle operations and that preharvest mitigation strategies should be considered to reduce the risk to beef products.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Escherichia coli O157 , Bovinos , Animais , Prevalência , Contagem de Colônia Microbiana , Antibiose , Distribuição Aleatória , Fezes/microbiologia , Infecções por Escherichia coli/epidemiologia , Salmonella , Ração Animal/microbiologia , Doenças dos Bovinos/microbiologia
2.
Toxins (Basel) ; 14(10)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36287947

RESUMO

Mycotoxin-contaminated feeds may negatively affect broiler chickens' health; hence, a sustainable approach to achieve mycotoxin elimination is necessary. This study aimed to evaluate the efficacy of red yeast (Sporidiobolus pararoseus; RY) as a novel mycotoxin binder in broilers. A total of 1440 one-week-old male broiler chicks were randomly assigned to 12 treatments in a 3 × 4 factorial design. The dietary treatments included three levels of mycotoxin-contaminated diets (0 µg kg−1 (0% of mycotoxin; MT), 50 µg kg−1 (50% MT), and 100 µg kg−1 (100% MT)) and four levels of mycotoxin binders (0.0 and 0.5 g kg−1 commercial binder, and 0.5 and 1.0 g kg−1 RY). Experimental diets were contaminated with aflatoxin B1, zearalenone, ochratoxin A, T-2 toxin, and deoxynivalenol in the basal diet. Furthermore, the parameters including feed intake, body weight, and mortality rate were recorded on a weekly basis. After feeding for 28 days, blood and organ samples were collected randomly to determine the blood biochemistry, relative organ weights, and gut health. The results indicated that mycotoxin-contaminated diets reduced the average daily weight gain (ADG), villus height (VH), and villus height per the crypt depth ratio (VH:CD) of the intestine, as well as the population of Lactobacillus sp. and Bifidobacterium sp. in the cecal (p < 0.05), whereas they increased the mycotoxins concentration in the blood samples and the apoptosis cells (TUNEL positive) in the liver tissue (p < 0.01) of broiler chicken. In contrast, RY-supplemented diets had better ADG values and lower chicken mortality rates (p < 0.05). Moreover, these combinations positively impacted the relative organ weights, blood parameters, bacteria population, intestinal morphology, and pathological changes in the hepatocytes (p < 0.05). In conclusion, RY supplementation effectively alleviated the toxicity that is induced by AFB1 and OTA, mainly, and could potentially be applied as a novel feed additive in the broiler industry.


Assuntos
Ração Animal , Produtos Biológicos , Micotoxinas , Animais , Masculino , Aflatoxina B1/toxicidade , Ração Animal/microbiologia , Galinhas/microbiologia , Dieta/veterinária , Micotoxinas/toxicidade , Toxina T-2/toxicidade , Zearalenona/toxicidade
3.
Toxins (Basel) ; 14(8)2022 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-36006214

RESUMO

Mycotoxins are toxic secondary metabolites produced by a variety of fungi, which when ingested can cause several deleterious effects to the health of humans and animals. In this work, the detection and quantification of six major mycotoxins (aflatoxins-AFLA, deoxynivalenol-DON, fumonisins-FUMO, ochratoxin A-OTA, T-2 toxin-T-2 and zearalenone-ZON) in 1749 samples of feed and feed ingredients for cattle, collected in Brazil between 2017 and 2021, was carried out using enzyme-linked immunosorbent assay (ELISA). In total, 97% of samples were contaminated with at least one mycotoxin, yet, very few samples exceeded the lowest European Union guidance values for cattle, and the estimated daily intake also showed a low risk for the animals. However, co-occurrences were widely observed, as 87% of samples contained two or more mycotoxins at the same time, and the presence of more than one mycotoxin at the same time in feed can lead to interactions. In conclusion, the contamination of feed and feed ingredients for cattle with mycotoxins in Brazil is very common. Hence, the monitoring of these mycotoxins is of significant importance for food safety.


Assuntos
Fumonisinas , Micotoxinas , Ração Animal/microbiologia , Animais , Brasil , Bovinos , Contaminação de Alimentos/análise , Fumonisinas/análise , Humanos , Micotoxinas/análise
4.
Am J Vet Res ; 83(9)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35895774

RESUMO

OBJECTIVE: To assess the potential contamination of commercial raw dog food products with bacteria of the Enterobacterales order that produce extended spectrum beta-lactamase (ESBL) and carbapenemase enzymes, determine risk factors for contamination, and understand isolate genetic diversity. SAMPLES: A total of 200 canine raw food products. METHODS: Products were cultured on selective chromogenic agar following enrichment steps. Whole-genome sequencing was performed for isolates that were confirmed to produce an ESBL. Isolates were characterized by antimicrobial resistance genes, and multilocus sequences typing, and compared to other isolates in the NCBI database for clonality. Preservation method and protein sources were assessed as potential risk factors for contamination with ESBL and carbapenemase-producing bacteria of the Enterobacterales order. RESULTS: No carbapenemase-producing Enterobacterales (CPE) were identified, but ESBL-producing Enterobacterales bacteria were isolated from 20/200 products (10.0%; 95% CI, 7.3 to 16.5%), all of which were frozen. Pork-derived protein source products were 8.1 times (P = .001; 95% CI, 2.53 to 26.2) more likely to carry ESBL-producing Enterobacterales bacteria than other protein sources. WGS analysis confirmed the presence of ESBL genes in a total of 25 distinct isolates (19 Escherichia coli, 5 Klebsiella pneumoniae, and 1 Citrobacter braakii). Genes encoding CTX-M type ESBL enzymes were the most common (24/25 isolates, 96.0%) with blaCTX-M-27 being the most common allele (8/25, 32.0%). CLINICAL RELEVANCE: Frozen, raw food products may serve as a route of transmission of ESBL-producing Enterobacterales bacteria to companion animals. Veterinarians should advise owners about the risks of raw food diets, including potential exposure to antimicrobial-resistant bacteria.


Assuntos
Ração Animal , Doenças do Cão , Enterobacteriaceae , Alimentos Crus , Ração Animal/microbiologia , Animais , Antibacterianos , Bactérias , Proteínas de Bactérias , Doenças do Cão/microbiologia , Cães , Enterobacteriaceae/isolamento & purificação , Contaminação de Alimentos , Alimentos Crus/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
5.
J Appl Microbiol ; 133(2): 1078-1088, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35611609

RESUMO

AIMS: Bacillus cereus is often responsible for foodborne diseases and both local and systemic infections in humans. Cases of infection in other mammals are rather rare. In this study, we report a B. cereus feed-related outbreak that caused the death of 6234 pigs in Italy. METHODS AND RESULTS: Massive doses of a Gram-positive, spore-forming bacterium were recovered from the animal feed, faeces of survived pigs and intestinal content of dead ones. The B. cereus MM1 strain was identified by MALDI-TOF MS and typified by RAPD-PCR. The isolate was tested for the production of PC-PLC, proteases, hemolysins and biofilm, for motility, as well as for the presence of genes encoding tissue-degrading enzymes and toxins. Antimicrobial resistance and pathogenicity in Galleria mellonella larvae were also investigated. Our results show that the isolated B. cereus strain is swimming-proficient, produces PC-PLC, proteases, hemolysins, biofilm and carries many virulence genes. The strain shows high pathogenicity in G. mellonella larvae. CONCLUSIONS: The isolated B. cereus strain demonstrates an aggressive profile of pathogenicity and virulence, being able to produce a wide range of determinants potentially hazardous to pigs' health. SIGNIFICANCE AND IMPACT OF STUDY: This study highlights the proficiency of B. cereus to behave as a devastating pathogen in swine if ingested at high doses and underlines that more stringent quality controls are needed for livestock feeds and supplements.


Assuntos
Ração Animal , Bacillus cereus , Infecções por Bactérias Gram-Positivas , Proteínas Hemolisinas , Ração Animal/microbiologia , Animais , Bacillus cereus/genética , Bacillus cereus/patogenicidade , Surtos de Doenças , Bactérias Gram-Positivas , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/veterinária , Proteínas Hemolisinas/genética , Larva/microbiologia , Mariposas/microbiologia , Peptídeo Hidrolases , Técnica de Amplificação ao Acaso de DNA Polimórfico , Esporos Bacterianos , Suínos
6.
Sci Rep ; 12(1): 7978, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35562415

RESUMO

This study aimed to evaluate the effects of Saccharomyces cerevisiae and Megasphaera elsdenii as direct fed microbials (DFM) in beef cattle finishing diets to alleviate acute ruminal lactic acidosis in vitro. A dual-flow continuous culture system was used. Treatments were a Control, no DFM; YM1, S. cerevisiae and M. elsdenii strain 1; YM2, S. cerevisiae and M. elsdenii strain 2; and YMM, S. cerevisiae and half of the doses of M. elsdenii strain 1 and strain 2. Each DFM dose had a concentration of 1 × 108 CFU/mL. Four experimental periods lasted 11 days each. For the non-acidotic days (day 1-8), diet contained 50:50 forage to concentrate ratio. For the challenge days (day 9-11), diet contained 10:90 forage to concentrate ratio. Acute ruminal acidosis was successfully established. No differences in pH, D-, L-, or total lactate were observed among treatments. Propionic acid increased in treatments containing DFM. For N metabolism, the YMM treatment decreased protein degradation and microbial protein synthesis. No treatment effects were observed on NH3-N concentration; however, efficiency of N utilization by ruminal bacteria was greater than 80% during the challenge period and NH3-N concentration was reduced to approximately 2 mg/dL as the challenge progressed.


Assuntos
Acidose , Megasphaera elsdenii , Acidose/metabolismo , Ração Animal/microbiologia , Animais , Bovinos , Dieta/veterinária , Fermentação , Concentração de Íons de Hidrogênio , Rúmen/microbiologia , Saccharomyces cerevisiae
7.
Toxins (Basel) ; 14(3)2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35324714

RESUMO

Mycotoxins are a group of toxic secondary metabolites produced in the food chain by fungi through the infection of crops both before and after harvest. Mycotoxins are one of the most important food safety concerns due to their severe poisonous and carcinogenic effects on humans and animals upon ingestion. In the last decade, insects have received wide attention as a highly nutritious, efficient and sustainable source of animal-derived protein and caloric energy for feed and food purposes. Many insects have been used to convert food waste into animal feed. As food waste might contain mycotoxins, research has been conducted on the metabolism and detoxification of mycotoxins by edible insects. The mycotoxins that have been studied include aflatoxins, fumonisins, zearalenone (ZEN), vomitoxin or deoxynivalenol (DON), and ochratoxins (OTAs). Aflatoxin metabolism is proved through the production of hydroxylated metabolites by NADPH-dependent reductases and hydroxylases by different insects. ZEN can be metabolized into α- and ß-zearalenol. Three DON metabolites, 3-, 15-acetyl-DON, and DON-3-glucoside, have been identified in the insect DON metabolites. Unfortunately, the resulting metabolites, involved enzymes, and detoxification mechanisms of OTAs and fumonisins within insects have yet to be identified. Previous studies have been focused on the insect tolerance to mycotoxins and the produced metabolites; further research needs to be conducted to understand the exact enzymes and pathways that are involved.


Assuntos
Insetos Comestíveis , Fumonisinas , Micotoxinas , Ocratoxinas , Eliminação de Resíduos , Zearalenona , Ração Animal/microbiologia , Animais , Contaminação de Alimentos/análise , Fumonisinas/análise , Micotoxinas/análise , Ocratoxinas/análise , Zearalenona/toxicidade
8.
Toxins (Basel) ; 14(2)2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35202171

RESUMO

This study addresses an advantageous application of a urinary zearalenone (ZEN) monitoring system not only for surveillance of ZEN exposure at the production site of breeding cows but also for follow-up monitoring after improvement of feeds provided to the herd. As biomarkers of effect, serum levels of the anti-Müllerian hormone (AMH) and serum amyloid A (SAA) concentrations were used. Based on the results of urinary ZEN measurement, two cows from one herd had urinary ZEN concentrations which were two orders of magnitude higher (ZEN: 1.34 mg/kg, sterigmatocystin (STC): 0.08 mg/kg in roughages) than the levels of all cows from three other herds (ZEN: not detected, STC: not detected in roughages). For the follow-up monitoring of the herd with positive ZEN and STC exposure, urine, blood, and roughage samples were collected from five cows monthly for one year. A monitoring series in the breeding cattle herd indicated that feed concentrations were not necessarily reflected in urinary concentrations; urinary monitoring assay by ELISA may be a simple and accurate method that reflects the exposure/absorption of ZEN. Additionally, although the ZEN exposure level appeared not to be critical compared with the Japanese ZEN limitation in dietary feeds, a negative regression trend between the ZEN and AMH concentrations was observed, indicating that only at extremely universal mycotoxin exposure levels, ZEN exposure may affect the number of antral follicles in cattle. A negative regression trend between the ZEN and SAA concentrations could also be demonstrated, possibly indicating the innate immune suppression caused by low-level chronic ZEN exposure. Finally, significant differences (p = 0.0487) in calving intervals between pre-ZEN monitoring (mean ± SEM: 439.0 ± 41.2) and post-ZEN monitoring (349.9 ± 6.9) periods were observed in the monitored five cows. These preliminary results indicate that the urinary ZEN monitoring system may be a useful practical tool not only for detecting contaminated herds under field conditions but also provides an initial look at the effects of long-term chronic ZEN/STC (or other co-existing mycotoxins) exposure on herd productivity and fertility.


Assuntos
Ração Animal/análise , Ração Animal/microbiologia , Criação de Animais Domésticos/métodos , Hormônio Antimülleriano/sangue , Monitoramento Biológico/métodos , Cruzamento/métodos , Proteína Amiloide A Sérica/análise , Zearalenona/urina , Animais , Bovinos , Feminino , Seguimentos
9.
Toxins (Basel) ; 14(2)2022 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-35202180

RESUMO

Feeding experiments with juvenile grass carp (Ctenopharyngodon idella) fed with genetically modified maize MON 810 or DAS-59122 dried leaf biomass were carried out with 1-, 3- and 6-month exposures. Dosages of 3-7 µg/fish/day Cry1Ab or 18-55 µg/fish/day Cry34Ab1 toxin did not cause mortality. No difference occurred in body or abdominal sac weights. No differences appeared in levels of inorganic phosphate, calcium, fructosamine, bile acids, triglycerides, cholesterol, and alanine and aspartame aminotransferases. DAS-59122 did not alter blood parameters tested after 3 months of feeding. MON 810 slightly decreased serum albumin levels compared to the control, only in one group. Tapeworm (Bothriocephalus acheilognathi) infection changed the levels of inorganic phosphate and calcium. Cry34Ab1 toxin appeared in blood (12.6 ± 1.9 ng/mL), but not in the muscle. It was detected in B. acheilognathi. Cry1Ab was hardly detectable in certain samples near the limit of detection. Degradation of Cry toxins was extremely quick in the fish gastrointestinal tract. After 6 months of feeding, only mild indications in certain serum parameters were observed: MON 810 slightly increased the level of apoptotic cells in the blood and reduced the number of thrombocytes in one group; DAS-59122 mildly increased the number of granulocytes compared to the near-isogenic line.


Assuntos
Ração Animal/microbiologia , Ração Animal/toxicidade , Toxinas de Bacillus thuringiensis/toxicidade , Carpas/anatomia & histologia , Carpas/crescimento & desenvolvimento , Carpas/imunologia , Zea mays/genética , Animais , Variação Genética , Genótipo , Herbivoria , Plantas Geneticamente Modificadas/genética , Zea mays/microbiologia
10.
Regul Toxicol Pharmacol ; 129: 105126, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35065094

RESUMO

Asterarcys quadricellulare (AQ) is a microalgal species with potential applications in improving the quality of animal feed, and safety studies on this species are lacking. Therefore, this study presents safety data on an industrially cultivated strain of AQ tested using the following Organisation for Economic Co-operation and Development (OECD) guidelines: acute skin irritation in rabbits; skin sensitisation in guinea pigs; acute eye irritation in rabbits; acute oral fixed-dose procedure in rats; and bacterial reverse mutation using the B.N. Ames technique. Results showed that AQ is non-irritant and non-sensitising to skin. AQ caused transient conjunctival lacrimation and redness; however, the scores for these clinical signs translated into low ocular irritation indices and classification of AQ as non-irritant to the eyes. An acute oral dose of AQ (2000 mg/kg) did not cause mortality, change in body weight gain, or any general, functional, and neurobehavioral clinical signs. In five strains of Salmonella typhimurium bacteria, treatment with AQ did not cause biologically or statistically significant changes in the number of revertant colonies, indicating that AQ does not cause mutagenic toxicity. This study demonstrates the safety of a heterotrophically-produced strain of AQ and supports its use as a safe and non-toxic feed ingredient.


Assuntos
Ração Animal/microbiologia , Criação de Animais Domésticos , Clorofíceas , Microalgas , Animais , Relação Dose-Resposta a Droga , Olho/efeitos dos fármacos , Cobaias , Testes de Mutagenicidade , Coelhos , Ratos , Pele/efeitos dos fármacos
11.
Pak J Biol Sci ; 25(1): 67-77, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35001577

RESUMO

<b>Background and Objectives:</b> Blue swimming crab, <i>Portunus pelagicus</i> (Linnaeus, 1758) are economically important sources of soft-shell products for export demand. However, increasing over-exploitation and pollution towards the sea resources affected the production of the <i>P. pelagicus</i>. The study aimed to determine the microalgal preference and feeding density of the monospecific (<i>Nannochloropsis oculata</i>, <i>Chlorella vulgaris</i>, <i>Isochrysis galbana</i> and <i>Chaetoceros wighamii </i>) by individual <i>P. pelagicus </i>larvae. <b>Materials and Methods:</b> In the microalgal preference study, one polystyrene tray with 100 holes was set up in the experimental tank (200 L) to place the 50 mL centrifuges tube. For feeding density study, the survival rate, Specific Growth Rate (SGR), Body Weight (BW) and Larvae Stage Index (LSI) of each larvae stage were collected from Zoea 1 (Z<sub>1</sub>) till megalopa. <b>Results:</b> Results for mean microalgal preference of individual larvae preferred most <i>Chlorella vulgaris</i> during Zoea 1 and 2, the larvae consumed the highest of <i>Nannochloropsis</i> <i>oculata</i>. For Zoea 3 and 4, the highest preference is <i>Isochrysis galbana</i>. For feeding regime, Zoea 1, larvae fed rotifer, <i>Artemia</i> and <i>Chlorella vulgaris</i> (T<sub>3</sub>), was the highest survival rate, Zoea 2 was larvae fed rotifer, <i>Artemia</i> and <i>Nannochloropsis oculata</i> (T<sub>5</sub>) and both Zoea 3 and Zoea 4, larvae fed rotifer, <i>Artemia</i> and <i>Isochrysis galbana</i> (T<sub>4</sub>) was the highest survival rate. The highest SGR and LSI were obtained in T<sub>4</sub> cultured in 14 days. <b>Conclusion:</b> In conclusion, the microalgal preference and feeding density of the selected microalgae are different depending on each larvae stage.


Assuntos
Ração Animal/normas , Braquiúros/crescimento & desenvolvimento , Microalgas/metabolismo , Ração Animal/microbiologia , Animais , Braquiúros/metabolismo
12.
Aust Vet J ; 100(5): 213-219, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35040117

RESUMO

Food for human and animal consumption can provide a vehicle for the transfer of pathogenic and antimicrobial-resistant bacteria into the food chain. We investigated the antimicrobial susceptibility of 453 Salmonella isolates collected from raw feed components, equipment and finished feed from 17 commercial feed mills in Australia between 2012 and 2021. Previous studies have found Salmonella prevalence and the diversity of Salmonella serotypes are greatest in the raw feed components. We, therefore, hypothesised that we would find a greater proportion of antimicrobial-resistant Salmonella isolates in the raw feed components compared to other sample types. We found that of 453 isolates tested, 356 (0.80) were susceptible to all antimicrobials tested, 49 (0.11) were nonsusceptible to streptomycin only and 48 (0.11) were resistant to two or more antimicrobials. Of the 48 antimicrobial-resistant isolates, 44 were found in feed milling equipment, two in raw feed components and two in finished feed. Statistical analysis, using a logistic regression with random effects model, found that the population-adjusted mean probability of detecting antimicrobial-resistant Salmonella isolates from feed milling equipment of 0.39, was larger than the probability of detecting resistant isolates in raw feed components 0.01, (P < 0.001) and in finished feed, 0.11, (P = 0.006). This propensity for antimicrobial-resistant bacteria to colonise feed milling equipment has not been previously reported. Further studies are required to understand the ecology of antimicrobial-resistant Salmonella in the feed milling environment.


Assuntos
Anti-Infecciosos , Salmonelose Animal , Ração Animal/microbiologia , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana/veterinária , Salmonella , Salmonelose Animal/epidemiologia , Sorogrupo
13.
J Sci Food Agric ; 102(3): 1193-1204, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34343355

RESUMO

BACKGROUND: Feed shortage is a factor restricting animal production in the tropics, therefore how to use natural woody plant resources as animal feed is an important strategy. RESULTS: Under the dual stress of an anaerobic and acidic environment, the microbial response during the fermentation of paper mulberry (PM) silage was found to be sensitive. The Gram-negative bacteria and mould died, and the dominant microbial community rapidly shifted to Gram-positive bacteria, resulting in a large reduction in microbial diversity and abundance. Exogenous bran additives interfered with the stress effects of the woody silage environment. Wheat bran (WB) accelerated the response of microorganisms to the anaerobic stress, and lactic acid bacteria became the dominant microbial community, thereby enhancing the lactic acid fermentation of silage, affecting the metabolic pathways of microorganisms, and improving the flavour and quality of the silage. Addition of rice bran made Enterobacter and Clostridium species quickly respond to the stress of the silage environment and become the predominant bacterial groups. In particular, anaerobic and spore-forming Clostridium species showed a strong tolerance to the silage environment, leading to butyric acid fermentation and protein degradation of the silage, and reducing its fermentation quality. CONCLUSION: The PacBio single-molecule real-time (SMRT) sequencing technology accurately revealed the microbial co-occurrence network and fermentation mechanism of silage. Our results indicate that PM can be used in combination with WB to prepare high-quality silage for animal production. © 2021 Society of Chemical Industry.


Assuntos
Ração Animal/microbiologia , Bactérias/metabolismo , Microbiota , Morus/química , Silagem/microbiologia , Ração Animal/análise , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Ácido Butírico/análise , Ácido Butírico/metabolismo , Fermentação , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Fungos/metabolismo , Ácido Láctico/análise , Ácido Láctico/metabolismo , Morus/microbiologia , Silagem/análise , Madeira/química , Madeira/microbiologia
14.
Microbiol Spectr ; 9(3): e0218321, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34937197

RESUMO

Black soldier fly larvae (BSFL; Hermetia illucens) are promising insects for the conversion of organic waste streams into valuable biomolecules. Such waste streams can contain foodborne pathogens. To assess this risk factor, this study evaluated the presence of Staphylococcus aureus in waste streams as a substrate ingredient for BSFL production as well as in the rearing process. First, the general microbiological quality and the occurrence of S. aureus were investigated for different waste streams. Staphylococcus aureus was abundantly present. Control of pH and water activity should avoid pathogens, which cannot grow in single-substrate ingredients, redeveloping when mixing streams for optimal substrate conditions for BSFL production. Next, it was investigated whether S. aureus present in the substrate was ingested and/or eradicated by BSFL. In inoculation trials, with S. aureus added to chicken feed as the substrate at 3 or 7 log CFU/g, the larvae showed a reducing effect on S. aureus. After 6 days, S. aureus counts were below the detection limit (2.0 log CFU/g) in all larvae samples and decreased in the substrate to <2.0 and <3.1 log CFU/g for inoculation levels of 3 and 7 log CFU/g, respectively. While this is promising, it is still recommended to monitor and control this pathogen in BSFL rearing. Intriguingly, screening of antimicrobial activity of dominant microorganisms associated with BSFL showed a clear activity of Trichosporon isolates against S. aureus. Future research should explore whether Trichosporon, which is frequently observed in BSFL, plays a role in controlling specific microorganisms, such as S. aureus. IMPORTANCE Given the increasing need for (more sustainable) methods to upcycle organic waste streams, the interest to rear insects, like black soldier fly larvae (BSFL), on such streams is increasing. This study reveals that S. aureus is abundantly present in such waste streams, which might be a point of attention for insect producers. At the same time, it reveals that when S. aureus was inoculated in chicken feed as the substrate, it was not detected in the larvae and was reduced in the substrate after 6 days. Future inoculation trials should investigate whether this reduction is substrate dependent or not. Toward the future, the role of the BSFL microbiota in controlling intestinal bacterial community homeostasis should be explored, because one of the dominant microorganisms associated with BSFL, Trichosporon spp., showed clear activity against S. aureus.


Assuntos
Ração Animal/microbiologia , Dípteros/crescimento & desenvolvimento , Dípteros/microbiologia , Larva/crescimento & desenvolvimento , Staphylococcus aureus/fisiologia , Águas Residuárias/microbiologia , Ração Animal/análise , Animais , Galinhas , Larva/microbiologia , Staphylococcus aureus/genética , Staphylococcus aureus/isolamento & purificação , Águas Residuárias/análise
15.
Int J Mol Sci ; 22(23)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34884465

RESUMO

Rhizopus oryzae is a fungus used to ferment tempeh in Indonesia and is generally recognized as safe (GRAS) for human consumption by the USA FDA. We previously assessed the effect of a tempeh extract on cortisol levels in zebrafish but did not include behavioral studies. Here, we measured the GABA content in three strains of Rhizopus oryzae, two isolated by us (MHU 001 and MHU 002) and one purchased. We then investigated the effect of tempeh on cortisol and the gut microbiota in a zebrafish experimental model. GABA concentration was the highest in MHU 002 (9.712 ± 0.404 g kg-1) followed by our MHU 001 strain and the purchased one. The fish were divided into one control group fed a normal diet and three experimental groups fed soybean tempeh fermented with one of the three strains of Rhizopus oryzae. After two weeks, individual fish were subjected to unpredicted chronic stress using the novel tank diving test and the tank light-dark test. Next-generation sequencing was used to analyze gut microbial communities and RT-PCR to analyze the expression of BDNF (brain-derived neurotrophic factor) gene and of other genes involved in serotonin signaling/metabolism in gut and brain. Tempeh-fed zebrafish exhibited increased exploratory behavior (less stress) in both tank tests. They also had significantly reduced gut Proteobacteria (include E. coli) (51.90% vs. 84.97%) and significantly increased gut Actinobacteria (include Bifidobacterium spp.) (1.80% vs. 0.79%). The content of Bifidobacteriumadolescentis, a "psychobiotic", increased ten-fold from 0.04% to 0.45%. Tempeh also increases BDNF levels in zebrafish brain. Rhizopus oryzae MHU 001 greatly improved the anti-stress effect of tempeh and microbiota composition in zebrafish gut.


Assuntos
Bactérias/classificação , DNA Bacteriano/genética , Rhizopus oryzae/fisiologia , Alimentos de Soja/microbiologia , Peixe-Zebra/fisiologia , Ração Animal/microbiologia , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Fator Neurotrófico Derivado do Encéfalo/genética , Fermentação , Microbioma Gastrointestinal , Sequenciamento de Nucleotídeos em Larga Escala , Hidrocortisona/análise , Rhizopus oryzae/química , Rhizopus oryzae/classificação , Análise de Sequência de DNA , Estresse Fisiológico , Proteínas de Peixe-Zebra/genética , Ácido gama-Aminobutírico/análise
16.
Toxins (Basel) ; 13(11)2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34822603

RESUMO

The contamination of food and feeds with mycotoxins poses a global health risk to humans and animals, with major economic consequences. Good agricultural and manufacturing practices can help control mycotoxin contamination. Since these actions are not always effective, several methods of decontamination have also been developed, including physical, chemical, and biological methods. Biological decontamination using microorganisms has revealed new opportunities. However, these biological methods require legal regulations and more research before they can be used in food production. Currently, only selected biological methods are acceptable for the decontamination of feed. This review discusses the literature on the use of microorganisms to remove mycotoxins and presents their possible mechanisms of action. Special attention is given to Saccharomyces cerevisiae yeast and lactic acid bacteria, and the use of yeast cell wall derivatives.


Assuntos
Descontaminação/métodos , Contaminação de Alimentos/prevenção & controle , Micotoxinas/toxicidade , Ração Animal/microbiologia , Animais , Microbiologia de Alimentos , Humanos
17.
Toxins (Basel) ; 13(11)2021 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-34822606

RESUMO

Mycotoxins can be found in many foods consumed by humans and animals. These substances are secondary metabolites of some fungi species and are resistant to technological processes (cooking, frying, baking, distillation, fermentation). They most often contaminate products of animal (beef, pork, poultry, lamb, fish, game meat, milk) and plant origin (cereals, processed cereals, vegetables, nuts). It is estimated that about 25% of the world's harvest may be contaminated with mycotoxins. These substances damage crops and may cause mycotoxicosis. Many mycotoxins can be present in food, together with mold fungi, increasing the exposure of humans and animals to them. In this review we characterized the health risks caused by mycotoxins found in food, pet food and feed. The most important groups of mycotoxins are presented in terms of their toxicity and occurrence.


Assuntos
Contaminação de Alimentos/análise , Micotoxicose/etiologia , Micotoxinas/toxicidade , Ração Animal/análise , Ração Animal/microbiologia , Animais , Fungos/metabolismo , Humanos , Carne/análise , Carne/microbiologia , Micotoxinas/análise , Metabolismo Secundário
18.
J Immunol Res ; 2021: 2549541, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746321

RESUMO

Clostridium perfringens (CP) is the principal pathogenic bacterium of chicken necrotic enteritis (NE), which causes substantial economic losses in poultry worldwide. Although probiotics are known to provide multiple benefits, little is known about the potential effects of Bacillus subtilis (B. subtilis) application in preventing CP-induced necrotic enteritis. In this study, 450 male Arbor Acres broilers were divided into 5 experimental treatments: A: basal diet (control group); B: basal diet and CP challenge (model group); C: CP challenge+10 mg/kg enramycin (positive control group); D: CP challenge+4 × 107 CFU/kg of feed B. subtilis PB6 (PB6 low-dosage group); and E: CP challenge+6 × 107 CFU/kg of feed B. subtilis PB6 (PB6 high-dosage group). There were 6 replicate pens per treatment with 15 broilers per pen. The present research examined the effect of Bacillus subtilis PB6 (B. subtilis PB6) on growth performance, mRNA expression of intestinal cytokines and tight junctions, and gut flora composition in broilers challenged with CP. The entire experiment was divided into two phases: the non-CP challenge phase (d0-18) and the CP challenge phase (d18-26). PB6 did not increase the growth performance during the first stage, but the PB6 high-dosage group was found to have larger body weight gain and ADFI during the CP challenge stage. Feed supplementation with PB6 reduced the lesion score of challenged chicks, with increased tight junction-related gene expression (occludin and ZO-1) and decreased TNF-α expression compared with CP-infected birds. A decrease in the abundance of Clostridium XI, Streptococcus, and Staphylococcus was observed after CP infection (P < 0.05), while supplementation with PB6 restored the ileal microbial composition. In conclusion, administration of B. subtilis PB6 improved growth performance, enhanced intestinal barrier function, and mitigated intestinal inflammation/lesions, which might be due to its restoring effects on the ileal microbial composition in CP-challenged broilers.


Assuntos
Ração Animal/microbiologia , Bacillus subtilis/fisiologia , Galinhas/microbiologia , Infecções por Clostridium/prevenção & controle , Clostridium perfringens/patogenicidade , Microbioma Gastrointestinal/fisiologia , Intestinos/microbiologia , Animais , Infecções por Clostridium/microbiologia , Dieta/métodos , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Probióticos
19.
Oxid Med Cell Longev ; 2021: 9967334, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34621467

RESUMO

Mycotoxins are key risk factors in human food and animal feed. Most of food-origin mycotoxins could easily enter the organism and evoke systemic toxic effects, such as aflatoxin B1 (AFB1), ochratoxin A (OTA), T-2 toxin, deoxynivalenol (DON), zearalenone (ZEN), fumonisin B1 (FB1), and 3-nitropropionic acid (3-NPA). For the last decade, the researches have provided much evidences in vivo and in vitro that the brain is an important target organ on mycotoxin-mediated neurotoxic phenomenon and neurodegenerative diseases. As is known to all, glial cells are the best regulator and defender of neurons, and a few evaluations about the effects of mycotoxins on glial cells such as astrocytes or microglia have been conducted. The fact that mycotoxin contamination may be a key factor in neurotoxicity and glial dysfunction is exactly the reason why we reviewed the activation, oxidative stress, and mitochondrial function changes of glial cells under mycotoxin infection and summarized the mycotoxin-mediated glial cell proliferation disorders, death pathways, and inflammatory responses. The purpose of this paper is to analyze various pathways in which common food-derived mycotoxins can induce glial toxicity and provide a novel perspective for future research on the neurodegenerative diseases.


Assuntos
Ração Animal/microbiologia , Astrócitos/efeitos dos fármacos , Microglia/efeitos dos fármacos , Micotoxinas/toxicidade , Doenças Neurodegenerativas/induzido quimicamente , Síndromes Neurotóxicas/etiologia , Ração Animal/análise , Animais , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Humanos , Microglia/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Síndromes Neurotóxicas/metabolismo , Estresse Oxidativo/efeitos dos fármacos
20.
PLoS One ; 16(10): e0259132, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34705867

RESUMO

The study aimed to investigate the efficacy of new mycotoxin adsorbents based on purified and activated bentonites combined with yeast and phytogenic compounds in fattening pigs. The experiment involved 96 pigs (31.2±2.4 kg). Control (C) group was fed a diet naturally contaminated with mycotoxins (5 mg/kg deoxynivalenol, DON) without an adsorbent. Treated groups received the feed with mycotoxin adsorbents: purified and activated bentonite (T1), purified and activated bentonite, yeast derivatives, phytogenic substances (T2), and purified, activated, and sulphurated bentonite with phytogenic substances (T3). Evaluated parameters involved growth performance, organ weight, small intestine and liver histopathology, complete blood count, serum biochemistry, antioxidant status of the organism and total and free DON content in urine. In all treated groups, an significant increase in intestinal GSH and GSH/GSSG ratio was observed when compared to C. No significant effects on liver and kidney weight, complete blood count, serum or intestinal malondialdehyde concentration, or total/free DON content in urine were observed. All adsorbents improved histopathological findings in the liver when compared to C. Moreover, T1, and T2 groups showed no presence of inflammatory reaction or necrotic changes in the livers. Although, mycotoxin adsorbents investigated in this study had no significant impact on pig growth performance, they reduced the oxidative stress, and on the tissue level they protected the jejunal tissue and liver parenchyma under deoxynivalenol challenge.


Assuntos
Ração Animal , Antídotos , Bentonita , Contaminação de Alimentos/análise , Intestino Delgado/efeitos dos fármacos , Ração Animal/análise , Ração Animal/microbiologia , Animais , Antídotos/administração & dosagem , Antídotos/farmacologia , Bentonita/administração & dosagem , Bentonita/farmacologia , Masculino , Micotoxinas/efeitos adversos , Suínos
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