RESUMEN
Mouse monoclonal antibodies (mAbs) reactive with Clostridium perfringens collagen adhesin protein (CNA) and necrotic enteritis B-like toxin (NetB) were developed. The best capture/detection mAb pairs for CNA and NetB were selected based on their affinity and specificity to develop sandwich enzyme-linked immunosorbent assays (ELISAs) to detect CNA and NetB proteins, respectively, in jejunal digesta samples from commercial broiler farms in the United States. Prior to the analysis of samples from commercial broiler flocks, the specificity and sensitivity of the CNA and NetB ELISAs were validated using sera, jejunal digesta, and fecal samples from chickens coinfected with Eimeria maxima and CNA+/NetB+C. perfringens in an animal model of necrotic enteritis (NE). Subsequently, a total of 251 field samples were collected from 74 commercial poultry farms. Among these, 18 samples were from 6 broiler farms that used certified organics (CO), and 155 samples were from 42 farms with nonantibiotics (NA). In jejunal digesta samples, CNA levels ranged from 0.02 to 0.59 ng/mL and NetB levels ranged from 0.09 to 1.91 ng/mL. CNA and NetB levels showed a positive correlation with each other (Pearson correlation coefficient r = 0.772, P < 0.001). CNA and NetB levels in jejunal digesta were significantly decreased in CO farms compared with those from NA farms (P < 0.001). In conclusion, these new C. perfringens antigen-specific sandwich ELISAs offer a sensitive and specific means to detect C. perfringens CNA and NetB proteins as biomarkers of early NE occurrence in field samples from commercial broiler chickens.
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Toxinas Bacterianas , Infecciones por Clostridium , Enteritis , Enfermedades de las Aves de Corral , Ratones , Animales , Toxinas Bacterianas/metabolismo , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/veterinaria , Pollos/metabolismo , Enteritis/diagnóstico , Enteritis/veterinaria , Clostridium perfringens , Biomarcadores , Colágeno , Diagnóstico Precoz , Enfermedades de las Aves de Corral/diagnósticoRESUMEN
A multicenter observational study was conducted on early lactation Holstein cows (n = 261) from 32 herds from 3 regions (Australia, AU; California, CA; and Canada, CAN) to characterize their risk of acidosis into 3 groups (high, medium, or low) using a discriminant analysis model previously developed. Diets ranged from pasture supplemented with concentrates to total mixed ration (nonfiber carbohydrates = 17 to 47 and neutral detergent fiber = 27 to 58% of dry matter). Rumen fluid samples were collected <3 h after feeding and analyzed for pH, and ammonia, d- and l-lactate, and volatile fatty acid (VFA) concentrations. Eigenvectors were produced using cluster and discriminant analysis from a combination of rumen pH, and ammonia, d-lactate, and individual VFA concentrations and were used to calculate the probability of the risk of ruminal acidosis based on proximity to the centroid of 3 clusters. Bacterial 16S ribosomal DNA sequence data were analyzed to characterize bacteria. Individual cow milk volume, fat, protein, and somatic cell count values were obtained from the closest herd test to the rumen sampling date (median = 1 d before rumen sampling). Mixed model analyses were performed on the markers of rumen fermentation, production characteristics, and the probability of acidosis. A total of 26.1% of the cows were classified as high risk for acidosis, 26.8% as medium risk, and 47.1% as low risk. Acidosis risk differed among regions with AU (37.2%) and CA (39.2%) having similar prevalence of high-risk cows and CAN only 5.2%. The high-risk group had rumen phyla, fermentation, and production characteristics consistent with a model of acidosis that reflected a rapid rate of carbohydrate fermentation. Namely, acetate to propionate ratio (1.98 ± 0.11), concentrations of valerate (2.93 ± 0.14 mM), milk fat to protein ratio (1.11 ± 0.047), and a positive association with abundance of phylum Firmicutes. The medium-risk group contains cows that may be inappetant or that had not eaten recently or were in recovery from acidosis. The low-risk group may represent cattle that are well fed with a stable rumen and a slower rumen fermentation of carbohydrates. The high risk for acidosis group had lower diversity of bacteria than the other groups, whereas CAN had a greater diversity than AU and CA. Rumen fermentation profile, abundance of ruminal bacterial phyla, and production characteristics of early lactation dairy cattle from 3 regions were successfully categorized in 3 different acidosis risk states, with characteristics differing between acidosis risk groups. The prevalence of acidosis risk also differed between regions.
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Acidosis , Enfermedades de los Bovinos , Femenino , Animales , Bovinos , Amoníaco/metabolismo , Rumen/metabolismo , Leche/química , Lactancia , Ácidos Grasos Volátiles/metabolismo , Dieta/veterinaria , Ácido Láctico/metabolismo , Carbohidratos/análisis , Acidosis/veterinaria , Acidosis/metabolismo , Fermentación , Concentración de Iones de Hidrógeno , Alimentación Animal/análisis , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/metabolismoRESUMEN
A multicenter observational study to evaluate genome-wide association was conducted in early-lactation Holstein cows (n = 293) from 36 herds in Canada, the USA, and Australia. Phenotypic observations included rumen metabolome, acidosis risk, ruminal bacterial taxa, and milk composition and yield measures. Diets ranged from pasture supplemented with concentrates to total mixed rations (nonfiber carbohydrates = 17 to 47, and neutral detergent fiber = 27 to 58% of dry matter). Rumen samples were collected <3 h after feeding and analyzed for pH, ammonia, d- and l-lactate, volatile fatty acid (VFA) concentrations, and abundance of bacterial phyla and families. Eigenvectors were produced using cluster and discriminant analyses from a combination of pH and ammonia, d-lactate, and VFA concentrations, and were used to estimate the probability of the risk of ruminal acidosis based on proximity to the centroid of 3 clusters, termed high (24.0% of cows), medium (24.2%), and low risk (51.8%) for acidosis. DNA of sufficient quality was successfully extracted from whole blood (218 cows) or hair (65 cows) collected simultaneously with the rumen samples and sequenced using the Geneseek Genomic Profiler Bovine 150K Illumina SNPchip. Genome-wide association used an additive model and linear regression with principal component analysis (PCA) population stratification and a Bonferroni correction for multiple comparisons. Population structure was visualized using PCA plots. Single genomic markers were associated with milk protein percent and the center logged ratio abundance of the phyla Chloroflexi, SR1, and Spirochaetes, and tended to be associated with milk fat yield, rumen acetate, butyrate, and isovalerate concentrations and with the probability of being in the low-risk acidosis group. More than one genomic marker was associated or tended to be associated with rumen isobutyrate and caproate concentrations, and the center log ratio of the phyla Bacteroidetes and Firmicutes and center log ratio of the families Prevotellaceae, BS11, S24-7, Acidaminococcaceae, Carnobacteriaceae, Lactobacillaceae, Leuconostocaceae, and Streptococcaceae. The provisional NTN4 gene, involved in several functions, had pleiotropy with 10 bacterial families, the phyla Bacteroidetes and Firmicutes, and butyrate. The ATP2CA1 gene, involved in the ATPase secretory pathway for Ca2+ transport, overlapped for the families Prevotellaceae, S24-7, and Streptococcaceae, the phylum Bacteroidetes, and isobutyrate. No genomic markers were associated with milk yield, fat percentage, protein yield, total solids, energy-corrected milk, somatic cell count, rumen pH, ammonia, propionate, valerate, total VFA, and d-, l-, or total lactate concentrations, or probability of being in the high- or medium-risk acidosis groups. Genome-wide associations with the rumen metabolome, microbial taxa, and milk composition were present across a wide geographical and management range of herds, suggesting the existence of markers for the rumen environment but not for acidosis susceptibility. The variation in pathogenesis of ruminal acidosis in the small population of cattle in the high risk for acidosis group and the dynamic nature of the rumen as cows cycle through a bout of acidosis may have precluded the identification of markers for acidosis susceptibility. Despite a limited sample size, this study provides evidence of interactions between the mammalian genome, the rumen metabolome, ruminal bacteria, and milk protein percentage.
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Acidosis , Enfermedades de los Bovinos , Femenino , Animales , Bovinos , Rumen/metabolismo , Amoníaco/metabolismo , Estudio de Asociación del Genoma Completo/veterinaria , Isobutiratos , Lactancia , Ácidos Grasos Volátiles/metabolismo , Proteínas de la Leche/análisis , Butiratos/metabolismo , Dieta/veterinaria , Bacterias/metabolismo , Lactatos/análisis , Acidosis/veterinaria , Concentración de Iones de Hidrógeno , Fermentación , Mamíferos/metabolismo , Enfermedades de los Bovinos/metabolismoRESUMEN
The objective of this study was to investigate the effects of dietary Bacillus subtilis supplementation on growth performance, jejunal lesion scores, oocyst shedding, and cytokine and tight junction protein expression in broiler chickens infected with Eimeria maxima. A total of 196 male day-old Ross 708 broilers were given a nonexperimental diet until 14 D of age. Then, all chickens were randomly assigned to one of seven dietary treatments: 2 basal diets (CON and NC); CON + virginiamycin (AB1); CON + bacitracin methylene disalicylate (BMD; AB2); CON + B. subtilis 1781 (PB1); CON + B. subtilis 747 (PB2); or CON + B. subtilis 1781 + 747 (PB3). At day 21, all chickens except those in the CON group were orally inoculated with E. maxima oocysts. At 7 D after E. maxima infection, the body weight gains of chickens fed PB2 and PB3 increased (P = 0.032) as much as those in chickens fed AB2. The body weight gain and feed efficiency of chickens fed PB2 were significantly increased (P < 0.001), and PB2 chickens showed (P = 0.005) the lowest lesion scores after E. maxima infection. Chickens fed PB2 showed (P < 0.05) lower mRNA expression of IL-1ß in infected chicken groups. Chickens in the AB1, AB2, PB1, PB2, and PB3 groups showed (P < 0.05) greater mRNA expression of junctional adhesion molecule 2 in jejunal tissue, whereas occludin expression increased (P < 0.05) in the jejunal tissue of chickens fed AB2 or PB2. Dietary B. subtilis supplementation significantly improved the growth performance of young chickens to a level comparable with that induced by virginiamycin or BMD without E. maxima infection. After infection with E. maxima, dietary virginiamycin and BMD significantly enhanced the epithelial barrier integrity, and the dietary B. subtilis 747 showed significantly enhanced growth performance, intestinal immunity, and epithelial barrier integrity. Together our results indicated that certain strains of B. subtilis provide beneficial effects on the growth of young broiler chickens and have the potential to replace antibiotic growth promoters.
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Bacillus subtilis/química , Pollos , Coccidiosis/veterinaria , Eimeria/fisiología , Inmunidad Innata/efectos de los fármacos , Mucosa Intestinal/inmunología , Enfermedades de las Aves de Corral/tratamiento farmacológico , Probióticos/administración & dosificación , Alimentación Animal/análisis , Animales , Pollos/crecimiento & desarrollo , Coccidiosis/tratamiento farmacológico , Coccidiosis/inmunología , Coccidiosis/parasitología , Dieta/veterinaria , Masculino , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/parasitologíaRESUMEN
The rumen is a complex ecosystem. It is the primary site for microbial fermentation of ingested feed allowing conversion of a low nutritional feed source into high quality meat and milk products. However, digestive inefficiencies lead to production of high amounts of environmental pollutants; methane and nitrogenous waste. These inefficiencies could be overcome by development of forages which better match the requirements of the rumen microbial population. Although challenging, the application of meta-proteomics has potential for a more complete understanding of the rumen ecosystem than sequencing approaches alone. Here, we have implemented a meta-proteomic approach to determine the association between taxonomies of microbial sources of the most abundant proteins in the rumens of forage-fed dairy cows, with taxonomic abundances typical of those previously described by metagenomics. Reproducible proteome profiles were generated from rumen samples. The most highly abundant taxonomic phyla in the proteome were Bacteriodetes, Firmicutes and Proteobacteria, which corresponded with the most abundant taxonomic phyla determined from 16S rRNA studies. Meta-proteome data indicated differentiation between metabolic pathways of the most abundant phyla, which is in agreement with the concept of diversified niches within the rumen microbiota.
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Bacterias/metabolismo , Proteínas Bacterianas/metabolismo , Microbioma Gastrointestinal/fisiología , Proteoma/metabolismo , Rumen/microbiología , Alimentación Animal , Animales , Bacterias/genética , Bacterias/aislamiento & purificación , Bovinos , ADN Bacteriano/aislamiento & purificación , Femenino , Fermentación/fisiología , Perfilación de la Expresión Génica , Redes y Vías Metabólicas/fisiología , Proteómica/métodos , ARN Ribosómico 16S/genéticaRESUMEN
Microbial colonization of the intestinal tract of commercial poultry is highly variable, likely due to the fact that poults and chicks are hatched and raised without exposure to adult birds and their microbiota. In industrial poultry production, it is hypothesized that most of the microbiota is obtained through horizontal transmission from the environment and very little by maternal transmission. The initial gut microbiota will therefore differ between flocks and companies based on environmental conditions at the hatchery. Day-old poults were collected from the hatchery of 2 companies at 3 different time points to monitor the initial colonizing microbiota by sequencing amplicons of marker genes for bacteria, lactic acid bacteria (LAB), fungi, and archaea. Bacterial colonizers were distinct by company (pseudo-F 38.7, P ≤ 0.05) with the predominant bacteria at Company A being clostridia, specifically Clostridium celatum group, C. paraputrificum, and C. tertium. Predominant bacteria at Company B were Enterobacteriaceae, belonging to 2 different groups, one that included Escherichia; Shigella and Salmonella and the other Klebsiella; Enterobacter; and others. The predominant LAB at both companies were Enterococcus faecalis and E. gallinarum, confirmed by sequencing the 16S ribosomal RNA (rRNA) gene of colonies picked from lactobacilli agar plate counts. The predominant fungi were Aspergillus niger and Saccharomyces cerevisiae, with Candida sake or Alterneria sp. in some samples of Company A. Archaeal sequences were detected only in a single poult from Company B. The initial gastrointestinal colonizers of poults vary across company and time, signifying a strong environmental effect on microbiota acquisition. There was an indication of maternal effects in certain breeder flocks from Company B. Further work is necessary to determine how this variability affects microbiota succession and impacts growth and production of the birds.
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Crianza de Animales Domésticos/métodos , Archaea/aislamiento & purificación , Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Microbioma Gastrointestinal , Pavos/microbiología , Animales , Archaea/clasificación , Bacterias/clasificación , ADN de Archaea/análisis , ADN Bacteriano/análisis , ADN de Hongos/análisis , Hongos/clasificación , Análisis de Secuencia de ADN/veterinariaRESUMEN
Cathodic protection (CP) is being increasingly used on reinforced concrete structures to protect steel reinforcing bars from corrosion in aggressive conditions. Due to the complexity of environmental conditions, the design specifications in national and international standards are still open to discussion to achieve both sufficient and efficient protection for reinforced concrete structures in engineering practices. This paper reports an experimental research to investigate the influence of chloride content on concrete resistivity, rebar corrosion rate and the performance of CP operation using different current densities. It aims to understand the correlation between the chloride content and concrete resistivity together with the CP current requirement, and to investigate the precision of the CP design criteria in standards.
RESUMEN
Opioids are very effective analgesics, but they are also highly addictive. Methadone is used to treat opioid dependence (OD), acting as a selective agonist at the µ-opioid receptor encoded by the gene OPRM1. Determining the optimal methadone maintenance dose is time consuming; currently, no biomarkers are available to guide treatment. In methadone-treated OD subjects drawn from a case and control sample, we conducted a genome-wide association study of usual daily methadone dose. In African-American (AA) OD subjects (n=383), we identified a genome-wide significant association between therapeutic methadone dose (mean=68.0 mg, s.d.=30.1 mg) and rs73568641 (P=2.8 × 10-8), the nearest gene (306 kilobases) being OPRM1. Each minor (C) allele corresponded to an additional ~20 mg day-1 of oral methadone, an effect specific to AAs. In European-Americans (EAs) (n=1027), no genome-wide significant associations with methadone dose (mean=77.8 mg, s.d.=33.9 mg) were observed. In an independent set of opioid-naive AA children being treated for surgical pain, rs73568641-C was associated with a higher required dose of morphine (n=241, P=3.9 × 10-2). Similarly, independent genomic loci previously shown to associate with higher opioid analgesic dose were associated with higher methadone dose in the OD sample (AA and EA: n=1410, genetic score P=1.3 × 10-3). The present results in AAs indicate that genetic variants influencing opioid sensitivity across different clinical settings could contribute to precision pharmacotherapy for pain and addiction.
Asunto(s)
Analgésicos Opioides/farmacología , Trastornos Relacionados con Opioides/genética , Dolor/genética , Adulto , Negro o Afroamericano/genética , Alelos , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/uso terapéutico , Relación Dosis-Respuesta a Droga , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Metadona/uso terapéutico , Persona de Mediana Edad , Morfina/uso terapéutico , Dolor/tratamiento farmacológico , Polimorfismo de Nucleótido Simple/genética , Receptores Opioides mu/genética , Estados Unidos , Población Blanca/genéticaRESUMEN
Nicotine withdrawal symptoms contribute to relapse in smokers, thereby prolonging the harm caused by smoking. To investigate the molecular basis for this phenomenon, we conducted a genome-wide association study of DSM-IV nicotine withdrawal in a sample of African American (AA) and European American (EA) smokers. A combined AA and EA meta-analysis (n=8021) identified three highly correlated single nucleotide polymorphisms (SNPs) in the protocadherin (PCDH)-α, -ß and -γ gene cluster on chromosome 5 that were associated with nicotine withdrawal (P<5 × 10-8). We then studied one of the SNPs, rs31746, in an independent sample of smokers who participated in an intravenous nicotine infusion study that followed overnight smoking abstinence. After nicotine infusion, abstinent smokers with the withdrawal risk allele experienced greater alleviation of their urges to smoke, as assessed by the Brief Questionnaire on Smoking Urges (BQSU). Prior work has shown that the PCDH-α, -ß and -γ genes are expressed in neurons in a highly organized manner. We found that rs31746 mapped to a long-range neuron-specific enhancer element shown previously to regulate PCDH-α, -ß and -γ gene expression. Using Braincloud mRNA expression data, we identified a robust and specific association between rs31746 and PCDH-ß8 mRNA expression in frontal cortex tissue (P<1 × 10-5). We conclude that PCDH-α, -ß and -γ gene cluster regulatory variation influences the severity of nicotine withdrawal. Further studies on the PCDH-α, -ß and -γ genes and their role in nicotine withdrawal may inform the development of novel smoking cessation treatments and reduce the harm caused by tobacco smoking.
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Cadherinas/genética , Fumar/genética , Síndrome de Abstinencia a Sustancias/genética , Tabaquismo/genética , Adulto , Negro o Afroamericano/genética , Cadherinas/metabolismo , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Femenino , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Familia de Multigenes/genética , Nicotina/metabolismo , Polimorfismo de Nucleótido Simple/genética , Protocadherinas , Recurrencia , Cese del Hábito de Fumar , Población Blanca/genéticaRESUMEN
SorCS2 is a member of the Vps10p-domain receptor gene family receptors with critical roles in the control of neuronal viability and function. Several genetic studies have suggested SORCS2 to confer risk of bipolar disorder, schizophrenia and attention deficit-hyperactivity disorder. Here we report that hippocampal N-methyl-d-aspartate receptor-dependent synaptic plasticity is eliminated in SorCS2-deficient mice. This defect was traced to the ability of SorCS2 to form complexes with the neurotrophin receptor p75NTR, required for pro-brain-derived neurotrophic factor (BDNF) to induce long-term depression, and with the BDNF receptor tyrosine kinase TrkB to elicit long-term potentiation. Although the interaction with p75NTR was static, SorCS2 bound to TrkB in an activity-dependent manner to facilitate its translocation to postsynaptic densities for synaptic tagging and maintenance of synaptic potentiation. Neurons lacking SorCS2 failed to respond to BDNF by TrkB autophosphorylation, and activation of downstream signaling cascades, impacting neurite outgrowth and spine formation. Accordingly, Sorcs2-/- mice displayed impaired formation of long-term memory, increased risk taking and stimulus seeking behavior, enhanced susceptibility to stress and impaired prepulse inhibition. Our results identify SorCS2 as an indispensable coreceptor for p75NTR and TrkB in hippocampal neurons and suggest SORCS2 as the link between proBDNF/BDNF signaling and mental disorders.
Asunto(s)
Receptores de Superficie Celular/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Hipocampo/metabolismo , Potenciación a Largo Plazo/fisiología , Ratones , Ratones Noqueados , Plasticidad Neuronal/fisiología , Neuronas/metabolismo , Receptor trkB/metabolismo , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/fisiología , Receptores de N-Metil-D-Aspartato/metabolismo , Transducción de Señal/efectos de los fármacosRESUMEN
UNLABELLED: Increasing the rumen-stable protein content of feed would lead to improved nitrogen utilisation in cattle, and less nitrogenous waste. Red clover (Trifolium pratense L.) is a high protein ruminant feed containing high polyphenol oxidase (PPO) activity. PPO mediated protein-quinone binding has been linked to protecting plant proteins from proteolysis. To explore the mechanism underlying the effect of PPO on protein protection in fresh forage feeds, proteomic components of feed down-boli produced from wild-type red clover and a low PPO mutant, at point of ingestion and after 4h in vitro incubation with rumen inoculum were analysed. Significant differences in proteomic profiles between wild-type and mutant red clover were determined after 4h incubation, with over 50% less spots in mutant than wild-type proteomes, indicating decreased proteolysis in the latter. Protein identifications revealed preferentially retained proteins localised within the chloroplast, suggesting that PPO mediated protection in the wild-type operates due to the proximity of target proteins to the enzyme and substrates, either diffusing into this compartment from the vacuole or are present in the chloroplast. This increased understanding of protein targets of PPO indicates that wider exploitation of the trait could contribute to increased protein use efficiency in grazing cattle. BIOLOGICAL SIGNIFICANCE: One of the main challenges for sustainable livestock farming is improving capture of dietary nitrogen by ruminants. Typically up to 70% of ingested protein-N is excreted representing a loss of productivity potential and a serious environmental problem in terms of nitrogenous pollution of lands and water. Identification of key characteristics of rumen-protected protein will deliver target traits for selection in forage breeding programmes. The chloroplastic enzyme PPO catalyzes the oxidation of phenols to quinones, which react with protein. Little is currently known about the intracellular protein targets of the products of PPO activity or the mechanism underlying protein complexing, including whether there is any specificity to the reaction. Here we have determined significant differences in the proteomes of freshly ingested down boli corresponding to the presence or absence of active PPO. These results show that in the presence of PPO the forage protein is less amenable to proteolysis and provide the novel information that the protected proteins are putatively chloroplastically located. These data also contribute to a growing evidence base that a chloroplastic PPO substrate exists in red clover in addition to the currently known vacuolar substrates.
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Catecol Oxidasa/metabolismo , Proteoma/análisis , Trifolium/metabolismo , Animales , Catecol Oxidasa/farmacología , Bovinos , Cloroplastos/metabolismo , Ingestión de Alimentos , Nitrógeno/metabolismo , Estado Nutricional , Proteínas de Plantas/metabolismo , Proteómica , Rumiantes , Trifolium/enzimología , Trifolium/genéticaRESUMEN
Salmonella enterica ssp. enterica is a foodborne pathogen able to cause disease in both humans and animals. Diverse serovars of this pathogen exist, some of which are host specific, causing a range of clinical symptoms from asymptomatic infection through morbidity and mortality. According to a 2007 survey by the USDA National Animal Health Monitoring System, fecal shedding of Salmonella from healthy cows occurs on 39.7% of dairy farms in the United States. Certain serovars are frequently isolated from dairy farms and the majority of isolates from the National Animal Health Monitoring System study were represented by 5 serovars; however, genotypic diversity was not examined. The objective of this study was to determine the diversity of clustered regularly interspaced short palindromic repeats (CRISPR) loci in Salmonella collected from 8 dairy farms with a previous history of salmonellosis. None of the cows or calves sampled on 2 of the 8 dairy farms were shedding Salmonella, although Salmonella was detected in a cow bedding sample on 1 of these farms. Salmonella populations were discrete on each farm, according to CRISPR typing, with the exception of an Anatum var. 15+ type on farms 5 and 6 and the Montevideo type on farms 1 and 2. One to 4 distinct CRISPR genotypes were identified per farm. The CRISPR typing differed within serovars, as Montevideo, Anatum var. 15+, and Muenster serovars had no overlap of spacer content, even on the same farm, reflecting between- and within-serovar genetic diversity. The dynamic nature of Salmonella populations was shown in a farm that was sampled longitudinally over 13.5 mo. Changes in serovar from 3,19:-:z27 to Montevideo was observed between the first sampling time and 8 mo later, with concomitant change in CRISPR alleles. The results indicate that Salmonella strains present in smaller dairy herds (<500 head) are specific to that farm and new Salmonella strains may emerge over time.
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Enfermedades de los Bovinos/epidemiología , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Variación Genética , Intoxicación Alimentaria por Salmonella/epidemiología , Salmonelosis Animal/epidemiología , Salmonella/genética , Animales , Secuencia de Bases , Bovinos , Enfermedades de los Bovinos/microbiología , Industria Lechera , Heces/microbiología , Femenino , Genotipo , Humanos , Minnesota/epidemiología , Datos de Secuencia Molecular , Salmonella/aislamiento & purificación , Intoxicación Alimentaria por Salmonella/microbiología , Salmonelosis Animal/microbiología , Análisis de Secuencia de ADN , Serogrupo , Wisconsin/epidemiologíaRESUMEN
We have used a translational Convergent Functional Genomics (CFG) approach to discover genes involved in alcoholism, by gene-level integration of genome-wide association study (GWAS) data from a German alcohol dependence cohort with other genetic and gene expression data, from human and animal model studies, similar to our previous work in bipolar disorder and schizophrenia. A panel of all the nominally significant P-value SNPs in the top candidate genes discovered by CFG (n=135 genes, 713 SNPs) was used to generate a genetic risk prediction score (GRPS), which showed a trend towards significance (P=0.053) in separating alcohol dependent individuals from controls in an independent German test cohort. We then validated and prioritized our top findings from this discovery work, and subsequently tested them in three independent cohorts, from two continents. A panel of all the nominally significant P-value single-nucleotide length polymorphisms (SNPs) in the top candidate genes discovered by CFG (n=135 genes, 713 SNPs) were used to generate a Genetic Risk Prediction Score (GRPS), which showed a trend towards significance (P=0.053) in separating alcohol-dependent individuals from controls in an independent German test cohort. In order to validate and prioritize the key genes that drive behavior without some of the pleiotropic environmental confounds present in humans, we used a stress-reactive animal model of alcoholism developed by our group, the D-box binding protein (DBP) knockout mouse, consistent with the surfeit of stress theory of addiction proposed by Koob and colleagues. A much smaller panel (n=11 genes, 66 SNPs) of the top CFG-discovered genes for alcoholism, cross-validated and prioritized by this stress-reactive animal model showed better predictive ability in the independent German test cohort (P=0.041). The top CFG scoring gene for alcoholism from the initial discovery step, synuclein alpha (SNCA) remained the top gene after the stress-reactive animal model cross-validation. We also tested this small panel of genes in two other independent test cohorts from the United States, one with alcohol dependence (P=0.00012) and one with alcohol abuse (a less severe form of alcoholism; P=0.0094). SNCA by itself was able to separate alcoholics from controls in the alcohol-dependent cohort (P=0.000013) and the alcohol abuse cohort (P=0.023). So did eight other genes from the panel of 11 genes taken individually, albeit to a lesser extent and/or less broadly across cohorts. SNCA, GRM3 and MBP survived strict Bonferroni correction for multiple comparisons. Taken together, these results suggest that our stress-reactive DBP animal model helped to validate and prioritize from the CFG-discovered genes some of the key behaviorally relevant genes for alcoholism. These genes fall into a series of biological pathways involved in signal transduction, transmission of nerve impulse (including myelination) and cocaine addiction. Overall, our work provides leads towards a better understanding of illness, diagnostics and therapeutics, including treatment with omega-3 fatty acids. We also examined the overlap between the top candidate genes for alcoholism from this work and the top candidate genes for bipolar disorder, schizophrenia, anxiety from previous CFG analyses conducted by us, as well as cross-tested genetic risk predictions. This revealed the significant genetic overlap with other major psychiatric disorder domains, providing a basis for comorbidity and dual diagnosis, and placing alcohol use in the broader context of modulating the mental landscape.
Asunto(s)
Alcoholismo/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genómica/métodos , Adulto , Alcoholismo/epidemiología , Animales , Modelos Animales de Enfermedad , Femenino , Alemania/epidemiología , Humanos , Masculino , Ratones , Ratones Noqueados , Polimorfismo de Nucleótido Simple , Riesgo , Estados Unidos/epidemiologíaRESUMEN
We report a GWAS of alcohol dependence (AD) in European-American (EA) and African-American (AA) populations, with replication in independent samples of EAs, AAs and Germans. Our sample for discovery and replication was 16 087 subjects, the largest sample for AD GWAS to date. Numerous genome-wide significant (GWS) associations were identified, many novel. Most associations were population specific, but in several cases were GWS in EAs and AAs for different SNPs at the same locus,showing biological convergence across populations. We confirmed well-known risk loci mapped to alcohol-metabolizing enzyme genes, notably ADH1B (EAs: Arg48His, P=1.17 × 10(-31); AAs: Arg369Cys, P=6.33 × 10(-17)) and ADH1C in AAs (Thr151Thr, P=4.94 × 10(-10)), and identified novel risk loci mapping to the ADH gene cluster on chromosome 4 and extending centromerically beyond it to include GWS associations at LOC100507053 in AAs (P=2.63 × 10(-11)), PDLIM5 in EAs (P=2.01 × 10(-8)), and METAP in AAs (P=3.35 × 10(-8)). We also identified a novel GWS association (1.17 × 10(-10)) mapped to chromosome 2 at rs1437396, between MTIF2 and CCDC88A, across all of the EA and AA cohorts, with supportive gene expression evidence, and population-specific GWS for markers on chromosomes 5, 9 and 19. Several of the novel associations implicate direct involvement of, or interaction with, genes previously identified as schizophrenia risk loci. Confirmation of known AD risk loci supports the overall validity of the study; the novel loci are worthy of genetic and biological follow-up. The findings support a convergence of risk genes (but not necessarily risk alleles) between populations, and, to a lesser extent, between psychiatric traits.
Asunto(s)
Alcoholismo/epidemiología , Alcoholismo/genética , Predisposición Genética a la Enfermedad/genética , Estudio de Asociación del Genoma Completo , Proteínas de Microfilamentos/genética , Proteínas de Transporte Vesicular/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Negro o Afroamericano/genética , Alcohol Deshidrogenasa/genética , Aminopeptidasas/genética , Mapeo Cromosómico , Estudios de Cohortes , Factores Eucarióticos de Iniciación/genética , Femenino , Estudios de Seguimiento , Genotipo , Humanos , Proteínas con Dominio LIM/genética , Masculino , Proteínas Mitocondriales/genética , Polimorfismo de Nucleótido Simple/genética , Escalas de Valoración Psiquiátrica , Estados Unidos/epidemiología , Población Blanca/genéticaRESUMEN
Animal production is a fundamental component of the food supply chain, and with an increasing global population production levels are set to increase. Ruminant animals in particular are valuable in their ability to convert a fibre-rich forage diet into a high-quality protein product for human consumption, although this benefit is offset by inefficiencies in rumen fermentation that contribute to emission of significant quantities of methane and nitrogenous waste. Through co-operation between plant and animal sciences, we can identify how the nutritional requirements of ruminants can be satisfied by high-quality forages for the future. Selective forage plant breeding has supported crop improvement for nearly a century. Early plant breeding programmes were successful in terms of yield gains (4% to 5% per decade), with quality traits becoming increasingly important breeding targets (e.g. enhanced disease resistance and digestibility). Recently, demands for more sustainable production systems have required high yielding, high-quality forages that enable efficient animal production with minimal environmental impact. Achieving this involves considering the entire farm system and identifying opportunities for maximising nutrient use efficiency in both forage and animal components. Forage crops of the future must be able to utilise limited resources (water and nutrients) to maximise production on a limited land area and this may require us to consider alternative plant species to those currently in use. Furthermore, new breeding targets will be identified as the interactions between plants and the animals that consume them become better understood. This will ensure that available resources are targeted at delivering maximum benefits to the animal through enhanced transformation efficiency.
Asunto(s)
Agricultura/economía , Cruzamiento/métodos , Plantas/genética , Selección Genética , Agricultura/tendencias , Alimentación Animal/análisis , AmbienteRESUMEN
UNLABELLED: This study investigated successional colonization of perennial ryegrass (PRG) by the rumen microbiota. PRG grown for 6 weeks in a greenhouse was incubated in sacco in the rumens of three Holstein × Freisian cows over a period of 24 h. PRG incubated within the rumen was subsequently harvested at various time intervals postincubation to assess colonization over time. DGGE-based dendograms revealed the presence of distinct primary (0-2 h) and secondary (4 h onwards) attached bacterial communities. Moving window analysis, band number and Shannon-Wiener diversity indices suggest that after 2 h a proportion of primary colonizing bacteria detach, to be replaced with a population of secondary colonizing bacteria between 2 and 4 h after entry of PRG into the rumen. Sequencing and classification of bands lost and gained between 2 and 4 h showed that the genus Prevotella spp. was potentially more prevalent following 4 h of incubation, and Prevotella spp. 16S rDNA-based QPCR supported this finding somewhat, as 2- to 4-h Prevotella QPCR data were greater but not significantly so. Low-temperature scanning electron microscopy showed that attached bacteria were predominantly enveloped in extracellular polymeric substances. In conclusion, colonization of fresh PRG is biphasic with primary colonization completed within 2 h and secondary colonization commencing after 4 h of attachment in this study. SIGNIFICANCE AND IMPACT OF THE STUDY: We investigated, over a 24-h period in sacco, whether attachment of rumen microbiota to perennial ryegrass (PRG) showed successional changes in diversity. Knowledge of the bacterial species that attach to PRG over time may aid our understanding of the temporal function of the attached microbiota and ultimately permit the development of novel strategies for improving animal production to meet the future demands for meat and milk.
Asunto(s)
Bacterias/crecimiento & desarrollo , Lolium/microbiología , Rumen/microbiología , Animales , Bacterias/clasificación , Bacterias/genética , Adhesión Bacteriana , Bovinos , ADN Ribosómico/análisis , Electroforesis en Gel de Gradiente Desnaturalizante , Femenino , Metagenoma , Prevotella/genética , Prevotella/crecimiento & desarrollo , Prevotella/fisiología , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Ruminant products are criticised for their SFA content relative to PUFA, although n-6:n-3 PUFA is desirable for human health ( < 4). Rumen protozoa are rich in unsaturated fatty acids due to engulfment of PUFA-rich chloroplasts. Increasing the chloroplast content of rumen protozoa offers a potentially novel approach to enhance PUFA flow to the duodenum and subsequent incorporation into meat and milk. We evaluated protozoal contribution to duodenal n-3 PUFA flow due to intracellular chloroplast content. A total of six Holstein × Friesian steers were fed, in a two-period changeover design, either straw:concentrate (S:C, 60:40; DM basis; S:C, low chloroplast) or fresh perennial ryegrass (PRG; high chloroplast). Following 12 d adaptation to diet, ruminal protozoal and whole duodenal samples were obtained. N and fatty acid content of whole duodenum and rumen protozoal samples were assessed and protozoal 18S rDNA quantitative PCR performed, enabling calculation of protozoal N flow. The ratio of individual fatty acids:N in rumen protozoal samples was calculated to obtain protozoal fatty acid flows. Based on total fatty acid flow, contribution (%) of protozoa to individual fatty acid flows was calculated. Protozoal fatty acid data and microscopical observations revealed that protozoa were enriched with 18 : 3n-3 following PRG feeding, compared with the S:C diet, due to increased intracellular chloroplast content. However, duodenal protozoal 18S rDNA concentration post PRG feeding was low, indicating rumen retention of the protozoa. Nutrition influences the 18 : 3n-3 content of protozoa; the challenge is to increase protozoal flow to the small intestine, while maintaining sustainable rumen densities.
Asunto(s)
Bovinos , Cloroplastos , ADN Protozoario/análisis , Duodeno/metabolismo , Ácidos Grasos/metabolismo , Rumen/parasitología , Animales , Cloroplastos/química , Cloroplastos/ultraestructura , Dieta/veterinaria , Duodeno/microbiología , Ácidos Grasos/análisis , MasculinoRESUMEN
Immune characteristics in 65 calves were evaluated in response to a Bacillus-based direct-fed microbial (DFM) provided in electrolyte scour treatment. Blood samples were analyzed for cell surface markers and α(1)-acid glycoprotein (AGP) concentration. AGP increased in scouring calves given electrolyte containing Bacillus at day 7 post-placement compared to scouring calves administered electrolyte alone and non-scouring calves, enhancing the inflammatory response for pathogen clearance. The Bacillus promotes T cell subsets including greater proportions of activated, mature cells (CD8(-)CD25(+), CD8(-)CD45RO(+), CD8(-)TCR1(+)) in calves given electrolyte containing Bacillus than scouring calves administered electrolyte alone and non-scouring calves. Also, the Bacillus may be alleviating inflammation at day 3 post-placement as the proportion of monocytes and granulocytes lacking L-selectin (CD172a(+)CD62L(-)) was greater in scouring calves given electrolyte compared to the other groups. Electrolyte containing Bacillus administered at the onset of scours influences components of innate and adaptive immune development during and following the scouring event.
Asunto(s)
Alimentación Animal/análisis , Bacillus subtilis/fisiología , Bovinos , Dieta/veterinaria , Electrólitos/uso terapéutico , Animales , Bovinos/inmunología , Enfermedades de los Bovinos/tratamiento farmacológico , Industria Lechera , Diarrea/tratamiento farmacológico , Diarrea/veterinaria , Suplementos Dietéticos , Glicoproteínas/metabolismo , Inflamación , Subgrupos Linfocitarios/efectos de los fármacos , Subgrupos Linfocitarios/fisiología , Masculino , Probióticos/uso terapéuticoRESUMEN
Evaluation of telomerase as an early detection biomarker for cancer has been hindered by a lack of reliable methods and standards for in situ histochemical measurement. Improved histochemical methods for measuring telomerase could expedite the acceptance of telomerase as a biomarker for use in diagnostic and clinical applications. The lack of a crystal structure for telomerase coupled with high variability in the antibodies available for immunohistochemical analysis has led to confusion in the literature regarding the binding specificity of these antibodies. We have developed an automated fluorescence microscopy protocol to assess the specificity of three fluorescently labeled telomerase antibodies and to quantify telomerase in cultured human tumor cells and in human fibroblast cells as a control. Significant differences in staining intensity and distribution were observed. Fluorescence measurements in these cell lines were compared to telomerase measured by the telomerase repeat amplification protocol, reverse transcription-polymerase chain reaction, and flow cytometry. This combination of measurements ensured a more complete quantitation of telomerase levels in each of the cell lines and could also be used as a model for validation of other biomarkers for clinical use.