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1.
Arch Microbiol ; 206(4): 182, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38502250

RESUMEN

In this study, 20 endophytic actinobacteria were isolated from different parts of peanut plants growing in cropland with low and high salt in West Bengal, India. The endophytes underwent a rigorous morphological, biochemical, and genetic screening process to evaluate their effectiveness in enhancing plant growth. About 20% of these isolates were identified as potential plant growth-promoting endophytic actinobacteria, which showed high 16S rRNA gene sequence similarity (up to 99-100%) with different species of Micromonospora. Among these isolates, Micromonospora sp. ASENR15 produced the highest levels of indole acetic acid (IAA) and gibberellic acid (GA), while Micromonospora sp. ASENL2, Micromonospora sp. ANENR4, and Micromonospora sp. ASENR12 produced the highest level of siderophore. Among these leaf and root endophytic Micromonospora, strain ANENR4 was tested for its plant growth-promoting attributes. ANENR4 can be transmitted into the roots of a healthy peanut plant, enhances growth, and colonize the roots in abundance, suggesting the potential agricultural significance of the strain. Moreover, the study is the first report of endophytic Micromonospora in peanuts with PGP effects. The outcomes of this study open avenues for further research on harnessing the benefits of this endophytic Micromonospora for optimizing plant growth in agriculture.


Asunto(s)
Actinobacteria , Micromonospora , Endófitos , Arachis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Bacterias/genética , Actinobacteria/genética , Raíces de Plantas/microbiología , Filogenia
2.
Fish Shellfish Immunol ; 145: 109321, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38122952

RESUMEN

Siberian sturgeon (Acipenser baerii) fry often face environmental stressors that can compromise their immune system, rendering them susceptible to opportunistic pathogens in intensive aquaculture systems. In this study, we explored the innovative use of chitosan nanoparticles loaded with Mentha piperita essential oil (MPO/CNPs) as a dietary supplement to improve the growth and immune responses of A. baerii. The results demonstrated that the addition of MPO/CNPs to the diet led to significant improvements in growth, as evidenced by increased red blood cell count, hematocrit, haemoglobin concentration, and reduced triglyceride levels. Furthermore, significant differences were observed in the immune parameters for the treatment groups receiving Mentha piperita essential oil loaded in chitosan nanoparticles (MPO/CNPs), including enhanced lysozyme activity, immunoglobulin M (IgM) levels, respiratory burst activity, and ACH50 activity. Additionally, gene expression analysis revealed upregulation of key immune-related genes in the MPO/CNPs-treated groups. These findings suggest that the use of MPO/CNPs can enhance the growth and bolster the immune defences of Siberian sturgeon fry, contributing to more sustainable production in intensive aquaculture environments.


Asunto(s)
Quitosano , Aceites Volátiles , Animales , Inmunidad Humoral , Mentha piperita , Dieta , Peces
3.
Appl Microbiol Biotechnol ; 108(1): 13, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38170309

RESUMEN

The cellulose-rich corncob residue (CCR) is an abundant and renewable agricultural biomass that has been under-exploited. In this study, two strategies were compared for their ability to transform CCR into cello-oligosaccharides (COS). The first strategy employed the use of endo-glucanases. Although selected endo-glucanases from GH9, GH12, GH45, and GH131 could release COS with degrees of polymerization from 2 to 4, the degrading efficiency was low. For the second strategy, first, CCR was efficiently depolymerized to glucose and cellobiose using the cellulase from Trichoderma reesei. Then, using these simple sugars and sucrose as the starting materials, phosphorylases from different microorganisms were combined to generate COS to a level up to 100.3 g/L with different patterns and degrees of polymerization. Using tomato as a model plant, the representative COS obtained from BaSP (a sucrose phosphorylase from Bifidobacterium adolescens), CuCbP (a cellobiose phosphorylase from Cellulomonas uda), and CcCdP (a cellodextrin phosphorylase from Clostridium cellulosi) were shown to be able to promote plant growth. The current study pointed to an approach to make use of CCR for production of the value-added COS. KEY POINTS: • Sequential use of cellulase and phosphorylases effectively generated cello-oligosaccharides from corncob residue. • Cello-oligosaccharides patterns varied in accordance to cellobiose/cellodextrin phosphorylases. • Spraying cello-oligosaccharides promoted tomato growth.


Asunto(s)
Celobiosa , Celulasa , Zea mays , Oligosacáridos/química , Fosforilasas
4.
Fish Shellfish Immunol ; 138: 108798, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37150237

RESUMEN

This paper describes the effects of flaxseed (Linum usitatissimum) oil (FSO) as a feed additive on growth performance, oxidative stress, immunity, and disease resistance in rainbow trout (Oncorhynchus mykiss). Eight-hundred-and-forty rainbow trout individuals (mean weight: 25.66 ± 1.33 g) were fed with different doses of FSO (0.5, 1, and 1.5%) ad libitum two times a day for 9 weeks. At the end of the feeding, growth performance was evaluated and the fish were challenged with two different bacteria (Yersinia ruckeri and Aeromonas hydrophila). At the end of the 3rd, 6th, and 9th weeks, blood and tissue samples were taken from 9 fish per treatment to evaluate innate immune response, cytokine gene expression levels, antioxidant enzyme activities and lipid peroxidation levels, and digestive enzyme activities. Determination of haematological parameters and histological examination was also carried out to evaluate the general health status of the fish. Results showed that the final weight and specific growth rate of FSO-supplemented fish increased significantly (p < 0.05). FSO-supplemented fish showed higher resistance to Y. ruckeri than the control group (p < 0.05). However, survival rates of all groups in A. hydrophila challenge test were similar (p > 0.05). Among the investigated innate immune response parameters, the potential killing activity of phagocytes, myeloperoxidase activity, and lysozyme activity increased in the FSO-supplemented groups (p < 0.05). Almost all cytokine gene expression levels in the experimental groups up-regulated especially after 9 weeks of feeding in the head kidney and intestine (p < 0.05). Similarly, superoxide dismutase and catalase activities were found to be significantly higher in the FSO group than in the control (p < 0.05) whereas, the lipid peroxidation levels drastically declined as a result of the FSO supplementation (p < 0.05). These results suggest that FSO can improve growth, enhance immune response, and lower oxidative damage in rainbow trout when supplemented at the rates of 0.5-1.5% for 9 weeks.


Asunto(s)
Enfermedades de los Peces , Lino , Oncorhynchus mykiss , Animales , Resistencia a la Enfermedad , Lino/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Antioxidantes/metabolismo , Estrés Oxidativo , Citocinas/metabolismo , Alimentación Animal/análisis
5.
Trop Anim Health Prod ; 55(1): 45, 2023 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-36692602

RESUMEN

This paper examined the pluripotent effect of supplementation of turmeric rhizome powder (TRP) (Curcuma longa) in growing Andaman local pigs. A total of 48 pigs were randomly allotted into four groups and fed diets containing TRP at 4 concentrations, that is, 0 (control group), 0.05 (treatment 1), 0.1 (treatment 2), and 0.2% (treatment 3) for 30 days. The mean body weight of pigs supplemented with 0.1% and 0.2% TRP was significantly higher than that of the control group (41.66 ± 0.44, 42.59 ± 0.33 vs 40.38 ± 0.30 kg; p ≤ 0.05) which indicated the effect of TRP as growth enhancer. A significant (p ≤ 0.05) decrease in serum concentration of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) was recorded in supplemented groups as compared to the control group. Creatinine kinase (U/l) decreased in all the treatment groups as compared to the control group. Total cholesterol, triglyceride, and low-density lipoprotein cholesterol decreased significantly after supplementation with 0.1% and 0.2% TRP in comparison to the control group. However, there was marked increase in high-density lipoprotein cholesterol (mg/dl) in all TRP-supplemented groups than the control group (27.67 ± 0.60 in T1, 32.76 ± 0.32 in T2, and 34.58 ± 0.37 in T3 vs. 23.73 ± 0.69 in control; p ≤ 0.05). Further, there was increase in antioxidant profile after TRP supplementation. Anti-inflammatory potentiality of TRP could also be appreciated since TRP supplementation downregulated (p ≤ 0.05) expression of IL-6, IL-1ß, and IFN-γ. Therefore, we perceive that this conflated approach is an example of its own kind to focus on modification of health status of pigs for more productivity and augmentation of immune response.


Asunto(s)
Curcuma , Rizoma , Animales , Porcinos , Polvos , Suplementos Dietéticos , Colesterol
6.
Fish Shellfish Immunol ; 116: 98-106, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34252543

RESUMEN

Medicinal herbs are used for growth promotion, disease control and other health benefits in aquaculture industry. Here, we examined the effect of dietary laurel-leaf cistus (Cistus laurifolius) ethanolic extract on growth performance, digestive enzyme activity, haematological profile and nonspecific immune responses in common carp (Cyprinus carpio). In addition, resistance against Aeromonas hydrophila infection was examined. Common carp was fed diets containing 0 (Control), 0.1 (CL0.1), 0.5 (CL0.5) and 1 (CL1) g kg-1 laurel-leaf cistus extract for 45 days. After 30 days, superoxide anion production (SAP) increased in CL0.1 and CL0.5 fish groups and at the end of the study all experimental fish groups had higher SAP compared to that of the control (P ˂ 0.05). Lysozyme activity (LA) was elevated in CL0.5 and CL1 treated groups on 30th day (P < 0.05), and this increase was only observed in C0.1 fish group at the end of study compared to control (P ˂ 0.05). Myeloperoxidase activity was significantly increased in CL0.5 and CL1 fish groups at the end of study. IL-1ßgene expression was significantly increased in treated fish in a dose-depended manner. Similar results were observed for transcription of IL-6 and IL-8 (P < 0.05). Anti-inflammatory cytokines, IL-10 and TGF-ß were highly up-regulated in the intestine and head kidney of CL treated fish groups compared to control (P < 0.05). At the end of experiment, significantly higher final body weight, weight gain, and specific growth rate were obtained in CL0.1 treated fish group compared to control. However, growth was negatively affected in CL1 fish group (P < 0.05). CL1 fish group had also a significantly higher FCR. Amylase activity was significantly increased in all experimental fish groups compared to control (P ˂ 0.05). Trypsin activity was decreased in CL0.1 and CL1 fish groups (P ˂ 0.05). WBC and RBC were significantly increased (P ˂ 0.05) in CL0.5 and CL1 fish groups, whereas haemoglobin, haematocrit, mean cell, mean cell haemoglobin contents were no significantly changed among control and treatment groups. Result of challenge test with A. hydrophila exhibited that survival rate in all treatment groups was significantly higher than that of control. These findings demonstrated that laurel-leaf cistus at 0.1 g kg-1 can be a suitable candidate for growth promotion, immune system induction and infection control in fish.


Asunto(s)
Carpas , Cistus , Enfermedades de los Peces/prevención & control , Infecciones por Bacterias Gramnegativas/prevención & control , Inmunidad Innata/efectos de los fármacos , Factores Inmunológicos/farmacología , Extractos Vegetales/farmacología , Aeromonas hydrophila , Amilasas/metabolismo , Animales , Recuento de Células Sanguíneas , Carpas/sangre , Carpas/genética , Carpas/inmunología , Carpas/metabolismo , Citocinas/genética , Etanol/química , Infecciones por Bacterias Gramnegativas/veterinaria , Riñón Cefálico/citología , Riñón Cefálico/inmunología , Lipasa/metabolismo , Muramidasa/inmunología , Hojas de la Planta/química , Solventes/química , Superóxidos/inmunología , Tripsina/metabolismo
7.
Fish Shellfish Immunol ; 108: 127-133, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33253908

RESUMEN

The present study aimed to investigate the potential effects of dietary marjoram extract on growth performance, health, and disease resistance in common carp, Cyprinus carpio. To this purpose, the fish were assigned into four treatments and fed by diets supplemented with 0 (control), 100, 200, and 400 mg marjoram extract kg-1 over eight weeks and then challenged with Aeromonas hydrophila. According to the results, 200 mg kg-1 dietary marjoram extract inclusion showed the highest final weight, weight gain, and specific growth rate, and lowest feed conversion ratio (FCR). White blood cell number, Red blood cells, hematocrit, hemoglobin, mean corpuscular volume and mean corpuscular hemoglobin were markedly increased particularly at 200 mg kg-1 treatment. Marjoram extract significantly increased plasma superoxide dismutase activity and decreased malondialdehyde level compared to the control treatment. Plasma complement and lysozyme activities and total immunoglobulin levels, mucosal complement, lysozyme and alkaline phosphatase activities and immunoglobulin levels were significantly increased compared to the control group. The lowest post-challenge survival rate was observed in the control treatment, whereas the highest value was related to the 200 mg kg-1 marjoram treatment. In conclusion, the present study demonstrated that, marjoram extract is a suitable feed supplements for common carp, as it stimulates the fish growth, antioxidant, and immune systems, which suppress the fish mortality during Aeromonas septicemia. According to the results, 200 mg marjoram extract kg-1 is recommended for carp feed formulation.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Carpas/inmunología , Enfermedades de los Peces/inmunología , Inmunidad Humoral , Inmunidad Mucosa , Origanum/química , Extractos Vegetales/metabolismo , Aeromonas hydrophila/fisiología , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Carpas/sangre , Carpas/crecimiento & desarrollo , Dieta/veterinaria , Suplementos Dietéticos/análisis , Resistencia a la Enfermedad/inmunología , Relación Dosis-Respuesta a Droga , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Extractos Vegetales/administración & dosificación , Extractos Vegetales/farmacología
8.
Molecules ; 26(4)2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33672045

RESUMEN

Hydrochar is a carbon-based material that can be used as soil amendment. Since the physical-chemical properties of hydrochar are mainly assigned to process parameters, we aimed at evaluating the organic fraction of different hydrochars through 13C-NMR and off-line TMAH-GC/MS. Four hydrochars produced with sugarcane bagasse, vinasse and sulfuric or phosphoric acids were analyzed to elucidate the main molecular features. Germination and initial growth of maize seedlings were assessed using hydrochar water-soluble fraction to evaluate their potential use as growth promoters. The hydrochars prepared with phosphoric acid showed larger amounts of bioavailable lignin-derived structures. Although no differences were shown about the percentage of maize seeds germination, the hydrochar produced with phosphoric acid promoted a better seedling growth. For this sample, the greatest relative percentage of benzene derivatives and phenolic compounds were associated to hormone-like effects, responsible for stimulating shoot and root elongation. The reactions parameters proved to be determinant for the organic composition of hydrochar, exerting a strict influence on molecular features and plant growth response.


Asunto(s)
Espectroscopía de Resonancia Magnética con Carbono-13 , Carbón Orgánico/química , Carbón Orgánico/farmacología , Cromatografía de Gases y Espectrometría de Masas , Desarrollo de la Planta/efectos de los fármacos , Compuestos de Amonio Cuaternario/química , Agua/química , Bioensayo , Raíces de Plantas/anatomía & histología , Raíces de Plantas/efectos de los fármacos , Brotes de la Planta/anatomía & histología , Brotes de la Planta/efectos de los fármacos , Semillas/efectos de los fármacos , Zea mays/efectos de los fármacos , Zea mays/crecimiento & desarrollo
9.
Br Poult Sci ; 62(1): 138-146, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32972211

RESUMEN

1. As the use of antibiotics as growth promoters has been banned in many regions, there has been an on-going search for possible alternative compounds, such as prebiotics and organic acids. 2. This study was conducted to investigate the influence of liquid whey (LW) and organic acid (ACIDAL® ML) supplementation on performance, eggs characteristics, gut pH and health status in laying hens. 3. Seven hundred and fifty, Isa Brown chicks were randomly assigned to five treatments groups (n = 150) and each treatment had five replicates of 30 birds each. The birds were reared for 48 weeks. The treatments were administered in the drinking water at doses of: 250 ml/l of LW (Lacto25), 500 ml/l of LW (Lacto50) or 1 ml/l of ACIDAL® ML (Aci). A positive control group (T+) was treated with 500 mg/l of Tetracolivit (an antibiotic). The negative control group (T-) did not receive any treatment in the drinking water. 4. Administration of LW or ACIDAL® ML in the drinking water reduced (P < 0.05) the pH in the crop, proventriculus, ileum and caeca, as well as total coliform bacteria and E. coli, but increased Lactobacillus spp. in the ileum and caecum, compared to the negative control. 5. Oviposition was earlier in the birds in both the Lacto50 and Aci groups. The weight of birds at first lay and point of lay in the four treated groups was higher than those in negative control group. Furthermore, egg production was increased by 10.44% in birds receiving Lacto25, but the weight and quality traits were unaffected, while the egg shell ratio was higher in the Aci group compared to the other treatments. 6. The data indicated that addition of LW or ACIDAL® ML improved hens' performance by modifying gut pH and microflora.


Asunto(s)
Agua Potable , Microbioma Gastrointestinal , Alimentación Animal/análisis , Animales , Pollos , Dieta/veterinaria , Suplementos Dietéticos/análisis , Huevos , Escherichia coli , Femenino , Concentración de Iones de Hidrógeno , Oviposición , Óvulo , Suero Lácteo
10.
World J Microbiol Biotechnol ; 37(10): 164, 2021 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-34458956

RESUMEN

Eucalyptus is the main species for the forestry industry in Brazil. Biotechnology and, more recently, gene editing offer significant opportunities for rapid improvements in Eucalyptus breeding programs. However, the recalcitrance of Eucalyptus species to in vitro culture is also a major limitation for commercial deployment of biotechnology techniques in Eucalyptus improvement. We evaluated various clones of Eucalyptus urophylla for their in vitro regeneration potential identified a clone, BRS07-01, with considerably higher regeneration rate (85%) in organogenesis, and significantly higher than most works described in literature. Endophytic bacteria are widely reported to improve in vitro plant growth and development. Hence, we believe that inclusion of endophytic plant growth promoting bacteria enhanced was responsible for the improved plantlets growth and development of this clone under in vitro culture. Metagenomic analysis was performed to isolate and characterize the prominent endophytic bacteria on BRS07-01 leaf tissue in vitro micro-cultures, and evaluate their impact on plant growth promotion. The analysis revealed the presence of the phyla Firmicutes (35%), Proteobacteria (30%) and much smaller quantities of Actinobacteria, Bacteroidetes, Gemmatimonadetes, Crenarchaeota, Euryarchaeota and Acidobacteria. Of the thirty endophytic bacterial strains isolated, eleven produced indole-3-acetic acid. Two of the isolates were identified as Enterobacter sp. and Paenibacillus polymyxa, which are nitrogen-fixing and capable of phosphate and produce ammonium. These isolates also showed similar positive effects on the germination of common beans (Phaseolus spp.). The isolates will now be tested as a growth promoter in Eucalyptus in vitro cultures. Graphical abstract for the methodology using cultivation independent and dependent methodologies to investigate the endophytic bacteria community from in vitro Eucalyptus urophylla BRS07-01.


Asunto(s)
Bacterias/aislamiento & purificación , Endófitos/aislamiento & purificación , Eucalyptus/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Brasil , ADN Bacteriano/genética , ADN Ribosómico/genética , Endófitos/clasificación , Endófitos/genética , Endófitos/metabolismo , Eucalyptus/crecimiento & desarrollo , Ácidos Indolacéticos/metabolismo , Metagenómica , Filogenia , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/microbiología , ARN Ribosómico 16S/genética
11.
World J Microbiol Biotechnol ; 37(4): 56, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33619649

RESUMEN

Methane utilizing bacteria (MUB) are known to inhabit the flooded paddy ecosystem where they play an important role in regulating net methane (CH4) emission. We hypothesize that efficient MUB having plant growth-promoting (PGP) attributes can be used for developing novel bio-inoculant for flooded paddy ecosystem which might not only reduce methane emission but also assist in improving the plant growth parameters. Hence, soil and plant samples were collected from the phyllosphere, rhizosphere, and non-rhizosphere of five rice-growing regions of India at the tillering stage and investigated for efficient methane-oxidizing and PGP bacteria. Based on the monooxygenase activity and percent methane utilization on NMS medium with methane as the sole C source, 123 isolates were identified and grouped phylogenetically into 13 bacteria and 2 yeast genera. Among different regions, a significantly higher number of isolates were obtained from lowland flooded paddy ecosystems of Aduthurai (33.33%) followed by Ernakulum (20.33%) and Brahmaputra valley (19.51%) as compared to upland irrigated regions of Gaya (17.07%) and Varanasi (8.94%). Among sub-samples, a significantly higher number of isolates were found inhabiting the phyllosphere (58.54%) followed by non-rhizosphere (25.20%) and rhizosphere (15.45%). Significantly higher utilization of methane and PGP attributes were observed in 30 isolates belonging to genera Hyphomicrobium, Burkholderia, Methylobacterium, Paenibacillus, Pseudomonas, Rahnella, and Meyerozyma. M. oryzae MNL7 showed significantly better growth with 74.33% of CH4 utilization at the rate of 302.9 ± 5.58 and exhibited half-maximal growth rate, Ks of 1.92 ± 0.092 mg CH4 L-1. Besides the ability to utilize CH4, P. polymyxa MaAL70 possessed PGP attributes such as solubilization of P, K, and Zn, fixation of atmospheric N and production of indole acetic acid (IAA). Both these promising isolates can be explored in the future for developing novel biofertilizers for flooded paddies.


Asunto(s)
Ecosistema , Metano/farmacología , Desarrollo de la Planta/efectos de los fármacos , Microbiología del Suelo , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacterias/patogenicidad , Biodiversidad , Enterobacteriaceae/aislamiento & purificación , India , Ácidos Indolacéticos , Cinética , Methylobacterium , Fijación del Nitrógeno , Oryza/microbiología , Paenibacillus polymyxa , Filogenia , Rizosfera , Suelo
12.
Rev Argent Microbiol ; 53(1): 78-83, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32891499

RESUMEN

The detection of characteristics associated with plant growth promotion has been studied frequently on bacteria and some of these detection methods were also used on yeasts. Sometimes, these methods, designed for prokaryotes, were used with no prior analysis regarding growth and production on eukaryotes. The aim of the present study was to assess and select the best suitable media for the detection of auxin-like compound production and inorganic-P solubilization on yeast strains. Already published media and new formulations, as well as yeasts with different genetic backgrounds were used for the comparison. Media were selected based on the adequate growth of yeast strains and reliable recognition of the studied features either by an easy detection of the metabolite (color or halo production) or simple medium preparation (low number of reagent and regular autoclaving). We propose here the use of the new DEV medium with glucose and with tryptophan to identify auxin-like compounds producers; and CPM medium (a variation from Custer's Chalk Medium) as base medium to identify yeasts capable of inorganic-P solubilization.


Asunto(s)
Ácidos Indolacéticos , Fosfatos , Medios de Cultivo , Suelo , Levaduras
13.
Appl Environ Microbiol ; 86(6)2020 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-31862718

RESUMEN

Increasing evidence exists for the role that cattle play in the epidemiology of campylobacteriosis. In this study, the prevalence and distribution of Campylobacter jejuni were longitudinally examined at the subspecies level in the beef cattle production continuum. Animals were subdivided into two groups: those that were not administered antibiotics and those that were administered the antimicrobial growth promoter chlortetracycline and sulfamethazine (AS700). Samples were longitudinally collected throughout the confined feeding operation (CFO) period and during the slaughter process, and C. jejuni was isolated and genotyped to assess subtype richness and to elucidate transmission dynamics from farm to fork. The bacterium was frequently isolated from cattle, and the bacterial densities shed in feces increased over the CFO period. Campylobacter jejuni was also isolated from digesta, hides, the abattoir environment, and carcasses. The administration of AS700 did not conspicuously reduce the C. jejuni densities in feces or within the intestine but significantly reduced the bacterial densities and the diversity of subtypes on abattoir samples. All cattle carried multiple subtypes, including clinically relevant subtypes known to represent a risk to human health. Instances of intra-animal longitudinal transmission were observed. Although clinically relevant subtypes were transmitted to carcasses via direct contact and aerosols, the bacterium could not be isolated nor could its DNA be detected in ground beef regardless of treatment. Although the evidence indicated that beef cattle represent a significant reservoir for C. jejuni, including high-risk subtypes strongly associated with the bovine host, they do not appear to represent a significant risk for direct foodborne transmission. This implicates alternate routes of human transmission.IMPORTANCE Limited information is available on the transmission of Campylobacter jejuni subtypes in the beef production continuum and the foodborne risk posed to humans. Cattle were colonized by diverse subtypes of C. jejuni, and the densities of the bacterium shed in feces increased during the confined feeding period. Campylobacter jejuni was readily associated with the digesta, feces, and hides of cattle entering the abattoir, as well as the local environment. Moreover, C. jejuni cells were deposited on carcasses via direct contact and aerosols, but the bacterium was not detected in the ground beef generated from contaminated carcasses. We conclude that C. jejuni bacterial cells associated with beef cattle do not represent a significant risk through food consumption and suggest that clinically relevant subtypes are transmitted through alternate routes of exposure.


Asunto(s)
Crianza de Animales Domésticos , Antibacterianos/uso terapéutico , Infecciones por Campylobacter/veterinaria , Campylobacter jejuni/fisiología , Enfermedades de los Bovinos/transmisión , Microbiología de Alimentos , Mataderos , Alberta , Animales , Derrame de Bacterias/efectos de los fármacos , Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/transmisión , Campylobacter jejuni/clasificación , Campylobacter jejuni/efectos de los fármacos , Campylobacter jejuni/aislamiento & purificación , Bovinos , Enfermedades de los Bovinos/microbiología , Clortetraciclina/uso terapéutico , Combinación de Medicamentos , Heces/microbiología , Sulfametazina/uso terapéutico
14.
Fish Physiol Biochem ; 46(4): 1295-1307, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32253566

RESUMEN

In this study, we examined changes occurred in blood parameters, immune responses, antioxidant enzyme activities, and growth performance of rainbow trout (Oncorhynchus mykiss) administered with ribwort plantain (RP) through feed. Fish (mean weight 36.56 ± 1.99 g) were fed a diet supplemented with an aqueous methanolic extract of RP at variable doses, 0 (control), 1 (RP1), 2 (RP2), and 3 g kg-1 (RP3) for 90 days. The final weight, weight gain, and specific growth rate were significantly increased in RP1, RP2, and RP3 treatment groups compared to that of the control. Among examined blood parameters, hemoglobin value in RP1 group (9.77 ± 0.10 g dl-1) only was significantly high on the 30th day of the study. When immune response parameters were evaluated, we observed that oxidative radical production and lysozyme activities were affected positively in experimental groups (P < 0.05). The highest oxidative radical production was determined in fish of RP3 group. Glutathione peroxidase and glucose 6 phosphate dehydrogenase were increased in RP3 group compared to control and other treatment groups. Based on these results, it is concluded that ribwort plantain promotes growth, enhances immune responses and antioxidant enzyme activities in rainbow trout, and therefore, may be used in aquaculture.


Asunto(s)
Aditivos Alimentarios/farmacología , Oncorhynchus mykiss , Extractos Vegetales/farmacología , Plantago/química , Alimentación Animal , Animales , Acuicultura , Catalasa/metabolismo , Recuento de Eritrocitos/veterinaria , Índices de Eritrocitos/efectos de los fármacos , Aditivos Alimentarios/administración & dosificación , Cromatografía de Gases y Espectrometría de Masas , Glucosafosfato Deshidrogenasa/metabolismo , Glutatión Peroxidasa/metabolismo , Hematócrito/veterinaria , Hemoglobinas/efectos de los fármacos , Hígado/enzimología , Oncorhynchus mykiss/sangre , Oncorhynchus mykiss/crecimiento & desarrollo , Oncorhynchus mykiss/inmunología , Oncorhynchus mykiss/metabolismo , Oxidación-Reducción/efectos de los fármacos , Extractos Vegetales/administración & dosificación , Superóxido Dismutasa/metabolismo
15.
Fish Physiol Biochem ; 46(5): 1883-1895, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32592128

RESUMEN

Peppermint is a popular herbal medicine due to its several pharmaceutical applications. In this study, peppermint powder was used as a feed additive to evaluate growth performance, hematological parameters, protein profile of skin mucus, and immune parameters, as well as growth hormone (GH), insulin-like growth factor (IGF), and 70 kDa heat shock protein (HSP70) gene expression in Caspian roach (Rutilus caspicus). The fingerlings (average weight of 2.40 ± 0.12 g) were fed with diet containing 0 (control), 2, 3, and 4 g/kg peppermint for 8 weeks. The addition of peppermint significantly enhanced the growth parameters and decreased the food conversion ratio. Hematological indices of fish fed with peppermint-supplemented diets were significantly different from the control group (P < 0.05). Soluble protein, alkaline phosphatase, and lysozyme enzyme activity in mucus samples showed an incremental trend by increasing the peppermint levels in the diet. Evaluation of mucosal immunity indicated a remarkable difference between the protein profile in treatments fed with peppermint-supplemented diets and the control group. A new protein band (approximately 27 kDa) was also found in the skin mucus of fish fed with the diet containing 4 g/kg peppermint, and the highest band density was observed in this treatment. The highest IGF and GH gene expression were observed in 4 g/kg peppermint treatment. There was a significant difference in HSP70 expression between the fish fed with peppermint powder and the control group (P < 0.05). Overall, the results showed that dietary oral administration of peppermint at 4 g/kg of feed can act as a growth promoter and immunostimulant.


Asunto(s)
Cyprinidae , Suplementos Dietéticos , Mentha piperita , Estrés Fisiológico , Fosfatasa Alcalina/metabolismo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Regulación de la Expresión Génica/efectos de los fármacos , Muramidasa/genética , Muramidasa/metabolismo , Polvos , Proteínas/metabolismo , Piel/efectos de los fármacos , Piel/inmunología
16.
Trop Anim Health Prod ; 52(6): 3467-3474, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32948968

RESUMEN

In a study to determine the growth-promoting effect of water-washed neem (Azadirachta indica A. Juss) fruit (WN) in West African Dwarf (WAD) rams, a total mixed ration was formulated with 0 (WN0), 2.5 (WN2.5), 5.0 (WN5), 7.5 (WN7.5), and 10.0 (WN10) % of WN inclusion. Twenty-five yearling rams (12.3 ± 2.0 kg) were assigned to one of the five dietary groups with five animals per group in a completely randomized design. Each group received the diet for 90 days inclusive of the initial 28 days used for anticoccidial efficacy trial. After the growth trial, three rams from each group were used for digestibility and nitrogen metabolism trial. Anticoccidial efficacy linearly increased (P = 0.002) with increased inclusion of WN and duration of feeding (P = 0.003). Feed intake (P = 0.018) and weight gain (P = 0.009) quadratically increased with WN5 inclusion compared to WN10. Optimal inclusion level of WN for daily weight gain was 5.1% (R2 = 0.30). Digestibility of crude protein was linearly and quadratically increased (P = 0.032; P = 0.031, respectively) with up to WN7.5 inclusion. Nitrogen retention was similar among the treatments. Incorporation of water-washed neem fruit in the diets of West African dwarf rams improved nutrient utilization and animal health by increasing anticoccidial efficacy, feed intake, and weight gain. This is an indication that water-washed neem fruit could be used as growth promoter in sheep production.


Asunto(s)
Azadirachta/química , Dieta/veterinaria , Frutas/química , Oveja Doméstica/crecimiento & desarrollo , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos/análisis , Relación Dosis-Respuesta a Droga , Masculino , Distribución Aleatoria
17.
J Anim Physiol Anim Nutr (Berl) ; 103(4): 1039-1049, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31016810

RESUMEN

This study investigated the influence of Bacillus-based probiotics on performance and intestinal health in broiler challenged with Clostridium perfringens-induced necrotic enteritis. One-day-old Arbor Acre (n = 480) were randomly assigned to four treatments with 10 cages of 12 birds: (a) basal diet negative control (NC), with no probiotics nor antibiotics formulated to contain 2,930 and 3,060 kcal/kg with 24.07 and 15.98% CP, for starter and finisher diet, respectively, (b) basal diet + enramycin (5 mg/kg), an antibiotic growth promoter (AGP); (c) basal diet + Bacillus subtilis B21 at 2 × 109 CFU per g (BS); (d) basal diet + Bacillus licheniformis B26 at 2 × 109 CFU per g (BL); growth performance, intestinal morphology, intestinal lesion scores, short-chain fatty acids (SCFAs) and mucosal barrier tight junction's (TJ) mRNA expression were assessed. NC- and BL-fed groups showed higher (p = 0.005) average daily feed intake from d1 to d21 than AGP and BS, whereas BS- and AGP-fed groups showed higher average daily weight gain from d22 to d42 and d1 to d42 of age. Higher mortality rate of (12.5%) and lower of (5.5%) were recorded in AGP and NC fed-groups respectively, lesion score was higher in BS and BL than in AGP, while no lesion was observed in NC group, results revealed higher duodenum and jejunum villus height to crypt depth (VH:CD) compared with NC and BS. Probiotics-fed groups showed higher total (SCFAs), acetic and butyric acid concentrations at d21 post-challenge (PC) than other groups. The expression of claudin-1 was upregulated in duodenum (d7) PC and in jejunum (d7) and (d21) PC in BL group, while at d21 PC, the expression of occludens was higher in jejunum and ileum by AGP and BL. The present study indicated both BS and BL have some similarity with AGP in preventing or partially preventing NE effect in broilers.


Asunto(s)
Bacillus licheniformis/fisiología , Bacillus subtilis/fisiología , Infecciones por Clostridium/veterinaria , Clostridium perfringens , Enteritis/veterinaria , Enfermedades de las Aves de Corral/prevención & control , Alimentación Animal/análisis , Animales , Pollos , Dieta/veterinaria , Suplementos Dietéticos , Enteritis/microbiología , Enfermedades de las Aves de Corral/microbiología , Probióticos , ARN Mensajero/genética , ARN Mensajero/metabolismo
18.
Avian Pathol ; 47(4): 339-351, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29635926

RESUMEN

The increasing occurrence of antibiotic-resistant bacteria combined with regulatory pressure and consumer demands for foods produced without antibiotics has caused the agricultural industry to restrict its practice of using antibiotic growth promoters (AGP) in food animals. The poultry industry is not immune to this trend, and has been actively seeking natural alternatives to AGP that will improve the health and growth performance of commercial poultry flocks. Bacillus probiotics have been gaining in popularity in recent years as an AGP alternative because of their health-promoting benefits and ability to survive the harsh manufacturing conditions of chicken feed production. This review provides an overview of several modes of action of some Bacillus direct-fed microbials as probiotics. Among the benefits of these direct-fed microbials are their production of naturally synthesized antimicrobial peptides, gut flora modulation to promote beneficial microbiota along the gastrointestinal tract, and various immunological and gut morphological alterations. The modes of action for increased performance are not well defined, and growth promotion is not equal across all Bacillus species or within strains. Appropriate screening and characterization of Bacillus isolates prior to commercialization are necessary to maximize poultry growth to meet the ultimate goal of eliminating AGP usage in animal husbandry.


Asunto(s)
Bacillus/fisiología , Pollos/crecimiento & desarrollo , Microbioma Gastrointestinal/efectos de los fármacos , Probióticos/farmacología , Alimentación Animal/análisis , Crianza de Animales Domésticos , Animales , Pollos/inmunología , Pollos/microbiología , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/microbiología , Aves de Corral
19.
Z Naturforsch C J Biosci ; 73(5-6): 247-256, 2018 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-29652669

RESUMEN

Plant growth-promoting bacteria that are also capable of suppressing plant pathogenic fungi play an important role in sustainable agriculture. There is a critical need for conducting research to discover, characterize and evaluate the efficacy of new strains of such bacteria in controlling highly aggressive plant pathogens. In this study, we isolated endophytic bacteria from medicinal plants of Bangladesh and evaluated their antagonistic capacity against an important phytopathogenic fungus Sclerotinia sclerotiorum. Growth-promoting effects of those isolates on cucumber and rice seedlings were also assessed. Among 16 morphologically distinct isolates, BDR-2, BRtL-2 and BCL-1 significantly inhibited the growth of S. sclerotiorum through induction of characteristic morphological alterations in hyphae and reduction of mycelial dry weight. When cucumber and rice seeds were treated with these endophytic bacteria, seven isolates (BCL-1, BDL-1, BRtL-2, BRtL-3, BDR-1, BDR-2 and BBoS-1) enhanced seed germination, seedling vigor, seedling growth and number of roots per plant at a varying level compared to untreated controls. All isolates produced high levels of indole-3-acetic acid (6 to 63 µg/mL) in vitro. Two most potential isolates, BDR-2 and BRtL-2, were identified as Bacillus amyloliquefaciens and B. subtilis, respectively, based on the 16S rRNA gene sequencing. These results suggest that endophytic Bacillus species from native medicinal plants have great potential for being used as natural plant growth promoter and biopesticides in sustainable crop production.


Asunto(s)
Ascomicetos/efectos de los fármacos , Bacillus/fisiología , Plantas Medicinales/microbiología , Semillas/crecimiento & desarrollo , Bacillus/clasificación , Bangladesh , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/microbiología , Endófitos/clasificación , Endófitos/fisiología , Oryza/crecimiento & desarrollo , Oryza/microbiología , Filogenia , Enfermedades de las Plantas/microbiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , ARN Ribosómico 16S/genética , Semillas/microbiología , Análisis de Secuencia de ARN
20.
Molecules ; 23(4)2018 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-29614824

RESUMEN

Biopolymers have become increasingly popular as biostimulators of plant growth. One of them, oligo-alginate, is a molecule that regulates plant biological processes and may be used in horticultural practice as a plant growth regulator. Biostimulators are mainly used to improve plant tolerance to abiotic stresses, including salinity. The aim of the study was to assess the effects of salinity and oligo-alginate of various molecular masses on the growth and physiological activity of Eucomis autumnalis. The species is an ornamental and medicinal plant that has been used for a long time in the traditional medicine of South Africa. The bulbs of E. autumnalis were coated using depolymerized sodium alginate of molecular mass 32,000; 42,000, and 64,000 g mol-1. All of these oligo-alginates fractions stimulated plant growth, and the effect was the strongest for the fraction of 32,000 g mol-1. This fraction was then selected for the second stage of the study, when plants were exposed to salt stress evoked by the presence of 100 mM NaCl. We found that the oligo-alginate coating mitigated the negative effects of salinity. Plants treated with the oligomer and watered with NaCl showed smaller reduction in the weight of the above-ground parts and bulbs, pigment content and antioxidant activity as compared with those not treated with the oligo-alginate. The study demonstrated for the first time that low molecular mass oligo-alginate may be used as plant biostimulator that limits negative effects of salinity in E. autumnalis.


Asunto(s)
Alginatos/química , Asparagaceae/efectos de los fármacos , Asparagaceae/metabolismo , Oligosacáridos/metabolismo , Cloruro de Sodio/farmacología , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Salinidad
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