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1.
Transgenic Res ; 24(1): 61-71, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25063310

RESUMEN

Competition between humans and livestock for cereal and legume grains makes it challenging to provide economical feeds to livestock animals. Recent increases in corn and soybean prices have had a significant impact on the cost of feed for pig producers. The utilization of byproducts and alternative ingredients in pig diets has the potential to reduce feed costs. Moreover, unlike ruminants, pigs have limited ability to utilize diets with high fiber content because they lack endogenous enzymes capable of breaking down nonstarch polysaccharides into simple sugars. Here, we investigated the feasibility of a transgenic strategy in which expression of the fungal cellulase transgene was driven by the porcine pancreatic amylase promoter in pigs. A 2,488 bp 5'-flanking region of the porcine pancreatic amylase gene was cloned by the genomic walking technique, and its structural features were characterized. Using GFP as a reporter, we found that this region contained promoter activity and had the potential to control heterologous gene expression. Transgenic pigs were generated by pronuclear microinjection. Founders and offspring were identified by PCR and Southern blot analyses. Cellulase mRNA and protein showed tissue-specific expression in the pancreas of F1 generation pigs. Cellulolytic enzyme activity was also identified in the pancreas of transgenic pigs. These results demonstrated the establishment of a tissue-specific promoter of the porcine pancreatic amylase gene. Transgenic pigs expressing exogenous cellulase may represent a way to increase the intake of low-cost, fiber-rich feeds.


Asunto(s)
Animales Modificados Genéticamente/genética , Celulasa/genética , Transgenes , Alimentación Animal , Animales , Animales Modificados Genéticamente/metabolismo , Hongos/enzimología , Hongos/genética , Humanos , alfa-Amilasas Pancreáticas/genética , Regiones Promotoras Genéticas , Sus scrofa
2.
J Dairy Sci ; 98(6): 3859-75, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25841968

RESUMEN

Goat ß-casein (CSN2) promoter has been extensively used to derive expression of recombinant therapeutic protein in transgenic goats; however, little direct evidence exists for signaling molecules and the cis-elements of goat CSN2 promoter in response to lactogenic hormone stimulation in goat mammary epithelial cells. Here, we use an immortalized caprine mammary epithelial cell line (CMC) to search for evidence of the above. Serial 5'-flanking regions deleted of promoter and intron 1 in goat CSN2 (-4,047 to +2,054) driven by firefly luciferase reporter gene were constructed and applied to measure promoter activity in CMC. The intron 1 region (+393 to +501) significantly decreased basal activity of the promoter. This finding contradicts other studies of the role of intron 1. The signal transducer and activator of transcription (STAT)5a played a significant role in activating promoter activity by prolactin stimulation. Hydrocortisone enhanced and prolonged the activity of STAT5a and promoter in CMC, but was independent of the glucocorticoid receptor response element. The minimum length of the CSN2 promoter segment in response to lactogenic stimulation was confirmed by 5' serial deletions. A cis-element located from -300 to -90 in proximal goat CSN2 promoter that is absent in bovine and human CSN2 promoter was newly identified. We demonstrated the presence of a STAT5a binding site (-102 to -82) and preservation of the guanosine nucleotide at position -90 based on responses to the presence of lactogenic hormone using internal deletions and point mutations of the predicted STAT5a binding site, and chromatin immunoprecipitation assay. Together, these findings demonstrate that the proximal -300 bp of goat CSN2 promoter containing the STAT5a binding site (-102 to -82) is the response element for lactogenic hormone stimulation. Additionally, intron 1 may be required for tissue or developmental stage-specific expression in mammary gland. The role of the far-distal regions of goat CSN2 promoter in high-level lactogenic hormone induction and specific expression require further examination.


Asunto(s)
Caseínas/genética , Cabras , Intrones/fisiología , Glándulas Mamarias Animales/metabolismo , Regiones Promotoras Genéticas , Animales , Sitios de Unión , Línea Celular Transformada , Células Epiteliales/metabolismo , Femenino , Prolactina/genética , Prolactina/farmacología , Receptores de Glucocorticoides/metabolismo , Elementos de Respuesta/efectos de los fármacos , Elementos de Respuesta/fisiología , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Proteínas Supresoras de Tumor
3.
Br J Cancer ; 106(3): 475-81, 2012 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-22187040

RESUMEN

BACKGROUND: Activating mutations of Fms-like tyrosine kinase 3 (FLT3) constitute a major driver in the pathogenesis of acute myeloid leukaemia (AML). Hence, pharmacological inhibitors of FLT3 are of therapeutic interest for AML. METHODS: The effects of inhibition of FLT3 activity by a novel potent FLT3 inhibitor, BPR1J-097, were investigated using in vitro and in vivo assays. RESULTS: The 50% inhibitory concentration (IC(50)) of BPR1J-097 required to inhibit FLT3 kinase activity ranged from 1 to 10 nM, and the 50% growth inhibition concentrations (GC(50)s) were 21±7 and 46±14 nM for MOLM-13 and MV4-11 cells, respectively. BPR1J-097 inhibited FLT3/signal transducer and activator of transcription 5 phosphorylation and triggered apoptosis in FLT3-driven AML cells. BPR1J-097 also showed favourable pharmacokinetic property and pronounced dose-dependent tumour growth inhibition and regression in FLT3-driven AML murine xenograft models. CONCLUSION: These results indicate that BPR1J-097 is a novel small molecule FLT-3 inhibitor with promising in vivo anti-tumour activities and suggest that BPR1J-097 may be further developed in preclinical and clinical studies as therapeutics in AML treatments.


Asunto(s)
Benzamidas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Sulfonamidas/uso terapéutico , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Animales , Benzamidas/química , Benzamidas/farmacología , Proliferación Celular/efectos de los fármacos , Células HEK293/efectos de los fármacos , Humanos , Indazoles/farmacología , Concentración 50 Inhibidora , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/patología , Masculino , Ratones , Ratones Desnudos , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Sulfonamidas/química , Sulfonamidas/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
4.
Anim Biotechnol ; 23(4): 278-90, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23134307

RESUMEN

The aim of this study was to investigate the genetic relationships between Taiwan black pigs (TBP) and other pig breeds by means of 15 fluorescent-labeled microsatellite markers. DNA from a total of 299 TBP from eight private farms and 234 purebred pigs representing six breeds and one synthetic line was used. Among the 15 microsatellite loci, polymorphism information content (PIC) values were all above 0.500; the numbers of observed alleles were all greater than the numbers of effective alleles (10.1 vs. 4.3 in averages). But 13 of the 15 microsatellite markers significantly deviated from the Hardy-Weinberg equilibrium (HWE); moreover, 13 of the 15 tested populations also deviated from the HWE. The inbreeding coefficient (F(IS)) indicated that two TBP populations (TBP-3 and TBP-4) had heterozygote deficiency (P < 0.01). The pair-wise F(ST), representing the genetic diversity between the two populations, ranged from 0.0332 to 0.3809. Meishan and Taoyuan breeds with black hair were previously considered closely related to TBP; however, the result of genetic relationship refuted this assumption. In conclusion, TBP is more similar to the European than Chinese breeds, and further investigations will need to clarify it more accurately.


Asunto(s)
Repeticiones de Microsatélite , Sus scrofa/genética , Animales , Análisis por Conglomerados , Variación Genética , Filogenia , Sus scrofa/clasificación , Taiwán
5.
Reprod Domest Anim ; 47(4): 553-61, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22044690

RESUMEN

The aim of this article is to demonstrate and characterize caprine mammary epithelial cells (CMC) immortalized with human telomerase reverse transcriptase (hTERT) gene. Five immortalized CMCs were assigned to either myoepithelial or luminal epithelial groups based on their morphology and expression of cell lineage-specific intermediate filaments. Telomeric repeat amplification protocol revealed various telomerase activities in CMCs associated with their distinct proliferation potential. Karyotypic analysis showed three CMCs retained their modal Capra hircus chromosome number (2n = 60), whereas the remaining two CMCs were abnormal at 2n = 19 and 2n = 36. CMCs with abnormal karyotypes lost p53 protein after chemical-induced DNA damage and showed anchorage-independent growth in soft agar assay. In terms of functional differentiation, luminal CMCs organized into alveolus-like structures when grown in Matrigel. Furthermore, αs1- and ß-casein gene was induced in luminal CMCs in response to lacto-hormones stimulation. Together these results showed that hTERT-immortalized CMCs retained major characteristics of mammary epithelial cells, and stability of the genome is required for maintaining normal mammary epithelium function. Application of CMCs can provide valuable models to study alveologenesis and lactogenesis of mammary epithelium and test the feasibility of recombinant constructs designed for the generation of transgenic livestock.


Asunto(s)
Células Epiteliales , Cabras , Glándulas Mamarias Animales/citología , Telomerasa/genética , Animales , Ciclo Celular , Línea Celular Transformada , Células Cultivadas , Daño del ADN , Células Epiteliales/enzimología , Células Epiteliales/fisiología , Células Epiteliales/ultraestructura , Femenino , Expresión Génica , Humanos , Cariotipificación/veterinaria , Proteínas Recombinantes de Fusión/genética , Células Madre , Telómero/química , Transfección
6.
Hernia ; 25(5): 1317-1324, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33548007

RESUMEN

PURPOSE: Occult inguinal hernias (IH) predispose peritoneal dialysis (PD) patients to the symptomatic IH formation after starting PD, which may cause complications. We conducted a retrospective study to assess the benefit/risk profile of routine laparoscopic examination for occult IH (RLEOH) with a synchronous repair in patients receiving PD catheter placement. METHODS: 432 patients were enrolled in this study. Patients with an internal hernia sac at all sizes were deemed to have occult IH. We retrospectively reviewed data including demographic characteristics and operative details. We also measured incidence rates of symptomatic IH, metachronous IH repair, and catheter survival over a follow-up period after starting PD. RESULTS: These patients were classified into the RLEOH group (n = 365) and the non-RLEOH group (n = 67). The RLEOH group was subdivided into occult IH with a synchronous repair (n = 17; the subgroup A), no occult IH (n = 339; the subgroup B), and occult IH without a synchronous repair (n = 9; the subgroup C). The incidence rates of symptomatic IH developed after staring PD in subgroups A, B, and C were 0, 5.6, and 22.2%, respectively, whereas that in the non-RLEOH group was 13.4%. The RLEOH group had a reduced hazard ratio for metachronous IH repair compared with the non-RLEOH group (HR = 0.426; 95% CI 0.195-0.930, p = 0.032). None of our patients suffered from herniorrhaphy-related complications. CONCLUSION: RLEOH with a synchronous repair during PD catheter insertion confers clinical benefits in reducing the risk of developing IH after starting PD and the need for a metachronous repair. This is a safe and reasonable approach.


Asunto(s)
Hernia Inguinal , Laparoscopía , Diálisis Peritoneal , Catéteres , Hernia Inguinal/epidemiología , Hernia Inguinal/cirugía , Herniorrafia/efectos adversos , Humanos , Diálisis Peritoneal/efectos adversos , Estudios Retrospectivos
7.
J Microsc ; 237(3): 275-81, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20500380

RESUMEN

The mechanism of high emission of InGaN-based multiple quantum wells, which exhibit exceptionally high light emission efficiency despite their high defect density, is still not fully understood. Here, we deal with this problem, showing the details of structure and formation of V defects in the multiple quantum wells and reviewing interpretations proposed so far. Then, we show a structural investigation of three-dimensional high-density quantum dots, fabricated instead of quantum wells in the active layer. The shape and size of the InGaN quantum dots and the SiN(x) masks for the growth of the dots have been revealed using high-angle annular dark field scanning transmission electron microscopy, energy dispersive X-ray spectroscopy nanoanalysis and high-resolution transmission electron microscopy.

8.
J Oral Rehabil ; 37(5): 346-51, 2010 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-20113389

RESUMEN

The survival rate of dental implants is markedly influenced by the quality of the bone into which they are placed. The purpose of this study was to determine the trabecular bone density at potential dental implant sites in different regions of the Chinese jawbone using computed tomography (CT) images. One hundred and fifty-four potential implant sites (15 in the anterior mandible, 47 in the anterior maxilla, 55 in the posterior mandible, and 37 in the posterior maxilla) were selected from the jawbones of 62 humans. The data were subjected to statistical analysis to determine any correlation between bone density (in Hounsfield units, HU) and jawbone region using the Kruskal-Wallis test. The bone densities in the four regions decreased in the following order: anterior mandible (530 +/- 161 HU, mean +/- s.d.) approximately equal anterior maxilla (516 +/- 132 HU) > posterior mandible (359 +/- 150 HU) approximately equal posterior maxilla (332 +/- 136 HU). The CT data demonstrate that trabecular bone density varies markedly with potential implant site in the anterior and posterior regions of the maxilla and mandible. These findings may provide the clinician with guidelines for dental implant surgical procedures (i.e., to determine whether a one-stage or a two-stage protocol is required).


Asunto(s)
Pueblo Asiatico , Mandíbula/anatomía & histología , Maxilar/anatomía & histología , Adulto , Anciano , Anciano de 80 o más Años , Densidad Ósea , China , Implantación Dental Endoósea , Humanos , Mandíbula/diagnóstico por imagen , Maxilar/diagnóstico por imagen , Persona de Mediana Edad , Planificación de Atención al Paciente , Estadísticas no Paramétricas , Tomografía Computarizada por Rayos X , Adulto Joven
9.
J Oral Rehabil ; 35(4): 283-90, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18321264

RESUMEN

This study investigated the effects of the stiffness of a maxillary sinus graft and the surface roughness of an immediately loaded implant using a non-linear three-dimensional finite element (FE) analysis (3D). Six FE models were created, including two stiffness values of grafted bone (345 and 3450 MPa of elastic modulus) and three conditions of implant-bone interfaces (Frictional coefficient of 0.3 for machined surface, 0.45 for rough implant surface and a bonded implant-bone interface for an osseointegrated implant). Computer tomographic images of a human skull were used to construct a posterior maxillary model. All implants were designed via the computer aided design software with a spiral threaded configuration. Three loading scenarios were investigated for each of the six models; axial loading and lateral loadings at 30 degrees and 60 degrees . The results showed that a 60 degrees lateral loading has scored the highest level of bone stresses among the three loading conditions. Immediately loaded implants with 0.3 frictional coefficient have suffered the highest bone stresses which were higher than those with bonded interface by about 57%. Increasing the frictional coeffecient to 0.45, however, did not show any benefits in reducing the peak bone stress. Raising the stiffness of grafted bone diminished the bone stress by about 10% in both the immediately loaded and the osseointegrated implants. It was also noted that increasing graft stiffness and implant surface roughness reduced the sliding at the implant-bone interface which may improve the implant stability and long-term survival.


Asunto(s)
Simulación por Computador , Implantes Dentales , Imagenología Tridimensional , Maxilar/patología , Tomografía Computarizada por Rayos X , Implantación Dental Endoósea , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Modelos Biológicos , Oseointegración , Diseño de Prótesis , Propiedades de Superficie
10.
Int J Clin Pract Suppl ; (147): 9-11, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15875609

RESUMEN

Coronary arterio-venous fistula (CAVF) is a rare coronary artery anomaly. We demonstrated the rare findings of a large congenital aorto-right atrial fistula with initial presentation of heart failure symptoms. Transthoracic echocardiography and transesophageal echocardiography made the accurate diagnosis. Further haemodynamic and angiographic study proved this large CAVF with extraordinary oxygen saturation step-up (26%) and large pulmonary to systemic shunt (Qp/Qs = 4.25). It was corrected by surgery because of evidence of heart failure and the possible risk of endocarditis and coronary steal effect.


Asunto(s)
Aorta/anomalías , Fístula Arteriovenosa/complicaciones , Anomalías de los Vasos Coronarios/complicaciones , Insuficiencia Cardíaca/etiología , Aorta/diagnóstico por imagen , Fístula Arteriovenosa/congénito , Fístula Arteriovenosa/diagnóstico por imagen , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Ecocardiografía Transesofágica , Atrios Cardíacos/anomalías , Atrios Cardíacos/diagnóstico por imagen , Humanos , Masculino , Persona de Mediana Edad
11.
Chest ; 70(03): 384-5, 1976 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-954466

RESUMEN

A 40-year-old man had a pathologically proved limited form of Wegener's granulomatosis complicating recurrent and massive hemoptysis from his cavitary pulmonary lesion. Of significant interest and clinical importance is the unusual location of the patient's pulmonary lesion, occurring in the posterior segment of the right upper lobe. This experience demonstrates that the location of the pulmonary nodule is not necessarily useful in distinguishing Wegener's granulomatosis from infectious granulomatosis, particularly tuberculosis.


Asunto(s)
Granulomatosis con Poliangitis/diagnóstico por imagen , Adulto , Granulomatosis con Poliangitis/patología , Granulomatosis con Poliangitis/cirugía , Hemoptisis/complicaciones , Humanos , Masculino , Radiografía
12.
Chest ; 76(3): 325-7, 1979 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-223818

RESUMEN

We report an unusual case of patent ductus arteriosus (PDA) co-existing with bronchial carcinoid. The initial radiographic presentation was hyperlucent lung. Causes and possible mechanisms of unilateral hypoperfusion of the lung are reviewed briefly. Useful diagnostic modalities in evaluating a hyperlucent lung are also discussed.


Asunto(s)
Neoplasias de los Bronquios/complicaciones , Carcinoma Adenoide Quístico/complicaciones , Conducto Arterioso Permeable/complicaciones , Pulmón/diagnóstico por imagen , Neoplasias de los Bronquios/cirugía , Carcinoma Adenoide Quístico/cirugía , Conducto Arterioso Permeable/diagnóstico , Conducto Arterioso Permeable/cirugía , Humanos , Pulmón/irrigación sanguínea , Masculino , Persona de Mediana Edad , Neumonectomía , Radiografía
13.
Chest ; 80(2): 230-2, 1981 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7249773

RESUMEN

We report a rare complication of transbronchial lung biopsy. A lung abscess developed after transbronchial biopsy of a peripheral mass lesion. Persistent fever, leukocytosis, and roentgenographic evidence of increase in size of the biopsied mass are useful clues for the diagnosis of pneumonia surrounding a tumor.


Asunto(s)
Broncoscopía/efectos adversos , Carcinoma de Células Escamosas/cirugía , Tecnología de Fibra Óptica , Absceso Pulmonar/etiología , Neoplasias Pulmonares/cirugía , Adulto , Antibacterianos/uso terapéutico , Humanos , Pulmón/diagnóstico por imagen , Absceso Pulmonar/diagnóstico por imagen , Absceso Pulmonar/tratamiento farmacológico , Absceso Pulmonar/cirugía , Masculino , Radiografía
14.
Brain Res Dev Brain Res ; 56(1): 131-6, 1990 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-2126227

RESUMEN

Growth cone particle (GCP) membranes prepared from fetal day 17 rat brain are comprised of 5 major polypeptides as analyzed by SDS-PAGE: tubulin (p52), actin (p42), pp46/GAP-43 and two unidentified species, p38 and p34. Antibodies specific for the alpha- and beta-subunits of G proteins recognize p38 and p34, respectively, on immunoblots following one- and two-dimensional electrophoretic separation. That G protein subunits comprise major species of GCP membrane-associated polypeptides suggests a role for G proteins in transmembrane signaling in nerve growth cones.


Asunto(s)
Axones/química , Proteínas de Unión al GTP/química , Proteínas de la Membrana/análisis , Proteínas del Tejido Nervioso/análisis , Secuencia de Aminoácidos , Animales , Encéfalo/embriología , Química Encefálica/fisiología , Datos de Secuencia Molecular , Fragmentos de Péptidos/análisis , Ratas , Homología de Secuencia de Ácido Nucleico
15.
J Nutr Biochem ; 10(9): 510-7, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15539330

RESUMEN

Studies of the dietary phytoestrogen biochanin A on cell proliferation of the cultured estrogen responsive cells human breast carcinoma MCF-7 showed that biochanin A exhibits biphasic regulation on MCF-7 cells. At concentrations of less than 10 microg/mL, cells respond to biochanin A by increasing cell growth and de novo DNA synthesis. The addition of biochanin A at concentrations of greater than 30 microg/mL significantly inhibited cell growth and DNA synthesis in a dose-dependent fashion, resulting in an IC(50) value of 40 microg/mL. The reversibility of these inhibitory effects by biochanin A appears also to be concentration dependent. Cells previously treated with high concentrations (>60 microg/mL) of biochanin A did not regain normal growth after treatment ceased. Biochanin A was cytostatic at low concentrations (<40 microg/mL) and cytotoxic at higher concentrations. Upon exposure to 100 microg/mL of biochanin A, cell morphology was severely altered, cell volume decreased, and condensation of cell components was clearly noticeable. In addition, biochanin A damaged cell membranes by increasing membrane permeability. These results suggest possible molecular and cellular mechanisms of the action of dietary phytoestrogens on estrogen target cells.

16.
Hepatogastroenterology ; 48(42): 1770-1, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11813621

RESUMEN

Pancreas divisum, the most common congenital variant of pancreatic ductal anatomy, occurs when the ventral and dorsal pancreatic-buds fail to fuse. Herein, we report on a 42-year-old male suffering from chronic pancreatitis with pancreas divisum. Magnetic resonance cholangiopancreatography confirmed this diagnosis. A pylorus-preserving pancreatoduodenectomy was then performed. Pathological examination of the pancreas demonstrated chronic pancreatitis without malignancy. The postoperative clinical course was uneventful, and the patient was discharged 10 days after surgery.


Asunto(s)
Conductos Pancreáticos/anomalías , Pancreaticoduodenectomía , Pancreatitis/cirugía , Adulto , Enfermedad Crónica , Constricción Patológica , Humanos , Masculino , Páncreas/diagnóstico por imagen , Conductos Pancreáticos/patología , Pancreaticoduodenectomía/métodos , Tomografía Computarizada por Rayos X
17.
J Anim Sci ; 69(3): 1279-89, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2061256

RESUMEN

Five sheep (average BW 62 kg) were fed 65% roughage: 35% concentrate diets (CP = 15%) in a 5 x 5 Latin square design to study the effects of combinations of defaunation and N supplements (soybean meal [SBM], corn gluten meal [CGM], blood meal [BM], urea, and casein) differing in ruminal degradation on ruminal microbial numbers and activity. Diets were fed twice daily (DM intake 1,759 g/d). Defaunation was accomplished with doses of 30 ml of alkanate 3SL3.sheep-1.d-1 for 3 d with 2 d of fasting. Treatment 1 (control) involved feeding faunated sheep a diet in which the supplemental N was 67% SBM N and 33% urea N. Treatment 2 involved feeding defaunated sheep the same diet as the control. Treatments 3, 4, and 5 involved feeding defaunated sheep diets in which the supplemental N source was either 67% CGM-BM N (CGM and BM combined on a 1:1 N ratio): 33% urea N, or 33% CGM-BM N:67% urea N or 33% CGM-BM N:33% urea N:33% casein N, respectively. Compared with the faunated control, defaunation (Treatments 2, 3, 4, and 5) increased (P less than .05) total direct counts of ruminal bacteria (2.7 vs 1.3 x 10(11)/ml), fungal zoospores (2.8 vs 1.4 x 10(5)/ml), and ruminal microbial protease activity (1.4 vs 1.0 mg azocasein/[ml ruminal fluid.h]). Defaunation did not have a consistent effect on ruminal microbial deaminase activity. Compared with the control, defaunation resulted in lower (P less than .05) total perchloric acid-soluble amino N in ruminal fluid at 4 and 10 h after the morning feeding. Defaunation did not decrease (P greater than .05) total free amino acid concentrations in ruminal fluid, but it altered the profile of free amino acids. Although defaunation increased (P less than .05) ruminal bacterial numbers, no increases in total microbial CP or OM concentrations in ruminal contents were observed.


Asunto(s)
Bacterias/crecimiento & desarrollo , Hongos/crecimiento & desarrollo , Nitrógeno/administración & dosificación , Rumen/microbiología , Ovinos/microbiología , Aminoácidos/análisis , Animales , Bacterias/metabolismo , Recuento de Colonia Microbiana , Desaminación , Endopeptidasas/metabolismo , Eucariontes/efectos de los fármacos , Hongos/metabolismo , Masculino , Péptidos/análisis , Rumen/metabolismo , Rumen/parasitología , Ovinos/metabolismo , Ovinos/parasitología
18.
J Anim Sci ; 69(3): 1290-9, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2061257

RESUMEN

Five ruminally, duodenally, and ileally cannulated sheep (average BW 62 kg) were fed 65% roughage: 35% concentrate diets (CP = 15%) in a 5 x 5 Latin square design to study the applicability of using a combination of defaunation with N supplements (soybean meal [SBM], corn gluten meal [CGM], blood meal [BM], urea, and casein) with different extents of ruminal degradation to manipulate microbial protein synthesis and amount of ruminal escape protein. Diets were fed twice daily (1,759 g DM/d). Defaunation was accomplished with 30-ml doses of alkanate 3SL3 (active ingredient: sodium lauryl diethoxy sulfate)/sheep daily for 3 d with 2 d of fasting. Treatment 1 (control) involved feeding faunated sheep a diet in which the supplemental N (45% of total dietary N) was 67% SBM N and 33% urea N. Treatment 2 involved feeding defaunated sheep the same diet as the control. Treatments 3, 4, and 5 involved feeding defaunated sheep diets in which the supplemental N source was either 67% CGM-BM (1:1 N ratio) N:33% urea N, or 33% CGM-BM N:67% urea N or 33% CGM-BM N:33% urea N:33% casein N, respectively. Compared with the faunated control, defaunation decreased (P less than .05) ruminal ammonia concentration (19 vs 26 mg/dl) and increased (P less than .05) CP flow to the duodenum (253 vs 214 g/d) due to a trend for increases in both bacterial (BCP) and nonbacterial (NBCP) CP flows.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Digestión , Nitrógeno/metabolismo , Rumen/metabolismo , Ovinos/metabolismo , Aminoácidos/metabolismo , Amoníaco/metabolismo , Alimentación Animal , Animales , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Eucariontes/efectos de los fármacos , Intestino Delgado/metabolismo , Masculino , Nitrógeno/administración & dosificación , Rumen/microbiología , Rumen/parasitología , Ovinos/microbiología , Ovinos/parasitología
19.
J Anim Sci ; 69(3): 1300-11, 1991 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1648067

RESUMEN

Five sheep (average BW 48 kg) with ruminal, duodenal, and ileal cannulas were fed 63% roughage: 37% concentrate diets (CP = 14.5%) in a 5 x 5 Latin square design to study effects of urea and sodium bicarbonate supplementation on nutrient digestion and ruminal characteristics of defaunated sheep. Diets were fed twice daily (DMI = 1,076 g/d). Defaunation was accomplished with 25-ml doses of alkanate 3SL3/sheep daily for 3 d. Control sheep were faunated (Treatment 1) and fed soybean meal as the major N supplement. Remaining sheep were maintained defaunated and fed either the same diet as Treatment 1 (Treatment 2), Treatment 1 with urea replacing 30% of the soybean meal N (Treatment 3), or Treatment 1 with 2% sodium bicarbonate in the diet (Treatment 4). Treatment 5 was a combination of Treatments 3 and 4. Compared with the faunated control, defaunation decreased (P less than .05) total tract DM, OM, NDF, ADF, and CP digestibilities (71.5 vs 69.4, 73.8 vs 71.7, 64.6 vs 61.4, 58.7 vs 55.8, and 74.2 vs 70.6%, respectively) and average (2 to 12 h postfeeding) ruminal fluid ammonia (23.5 vs 13.7 mg/dl) and isobutyrate (.9 vs .7 mM) concentrations. However, defaunation increased (P less than .05) linoleic and linolenic acid flows (.58 vs .45 g C18:2/d; .17 vs .14 g C18:3/d) to and disappearance (.50 vs .39 g C18:2/d; .14 vs .11 g C18:3/d) from the small intestine. Urea supplementation increased (P less than .05) total tract DM (70.2 vs 68.6%) and OM (72.3 vs 71.0%) digestibilities of defaunated sheep but lowered (P less than .05) ruminal fluid isobutyrate concentration (.6 vs .8 mM). Sodium bicarbonate supplementation increased (P less than .05) ruminal fluid pH (6.4 vs 6.2), isobutyrate concentration (.75 vs .60 mM), total tract ADF digestibility (57.6 vs 54.2%), and ruminal NDF (41.6 vs 28.5%), ADF (36.6 vs 22.8%), and CP (-5.5 vs -26.8%) digestibilities in defaunated sheep. Dietary supplementation of urea or sodium bicarbonate increased nutrient digestion by defaunated sheep.


Asunto(s)
Bicarbonatos/metabolismo , Digestión , Rumen/metabolismo , Ovinos/metabolismo , Sodio/metabolismo , Urea/metabolismo , Absorción , Amoníaco/análisis , Animales , Bacterias/crecimiento & desarrollo , Bacterias/metabolismo , Bicarbonatos/administración & dosificación , Colina/metabolismo , Fibras de la Dieta/administración & dosificación , Fibras de la Dieta/metabolismo , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Ingestión de Alimentos , Eucariontes/efectos de los fármacos , Ácidos Grasos Volátiles/análisis , Concentración de Iones de Hidrógeno , Intestino Delgado/metabolismo , Masculino , Rumen/microbiología , Ovinos/microbiología , Sodio/administración & dosificación , Bicarbonato de Sodio , Urea/administración & dosificación
20.
J Anim Sci ; 65(1): 244-55, 1987 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-3038821

RESUMEN

An in situ trial (randomized complete block design) using cows, and a site and extent of digestion trial (Latin square design) using sheep were conducted to study the potential of corn fiber (CF), cottonseed hulls (CSH), oat hulls (OH) and soybean hulls (SH) as roughage sources for ruminants. Two feedlot trials with steers and one with lambs (completely randomized design with factorial arrangements of treatments) were conducted to study the potential of CF and SH as energy supplements relative to corn. In situ rate of ruminal dry matter (DM) disappearance (3 to 36 h) and extent of DM disappearance (36 h) indicated that CF and SH were more fermentable in the rumen compared with OH or CSH, with SH being the most fermentable. Total tract digestibilities of DM, organic matter (OM), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were above 70% for sheep fed CF and SH diets, and were 50% or less for sheep fed OH and CSH diets. A ranking of by-products in terms of nutritive value followed the trend: CF greater than SH greater than OH greater than CSH. Lamb feedlot trial data showed that CF was of similar nutritive value to corn and of higher nutritive value than SH at the 50% level of supplementation. Corn-fed lambs responded better than CF- or SH-fed lambs at the 70% level of supplementation. Data from steer feedlot trials showed that CF was of similar quality to corn and of higher quality than SH. Dramatic differences exist in by-product feed utilization by ruminants. All by-products tested appeared to have some usefulness as dietary components.


Asunto(s)
Alimentación Animal , Bovinos/metabolismo , Fibras de la Dieta/metabolismo , Ovinos/metabolismo , Animales , Aceite de Semillas de Algodón , Digestión , Grano Comestible , Femenino , Masculino , Glycine max , Zea mays
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