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1.
J Dairy Sci ; 88(10): 3563-74, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16162530

RESUMEN

Four experiments were conducted to evaluate factors influencing concentrations of plasma total gossypol (TG) in 30 Holstein steers fed cottonseed products. At the end of each 28-d experiment, steers were weighed and blood samples were collected and analyzed for plasma TG concentrations. During the entire study, steers did not show any overt signs of gossypol toxicity. In the 28 d before experiment 1, 30 steers with a body weight (BW) of 273 kg were fed a standardization diet with 15.0% Upland whole cottonseed (WCS) that resulted in a mean intake of 9.08 g/d of TG per steer/d and a plasma TG of 1.66 microg/mL. In experiment 1, 30 steers were fed 1 of 5 diets with 15.0% Upland WCS, but different levels of supplemental Fe [0, 150, 300, 450, and 600 mg/kg of diet dry matter (DM)]. Average daily gain was not affected by level of Fe in the diet, but DM intake, plasma TG, and plasma TG response decreased linearly as Fe in diets increased. In experiment 2, steers were fed diets with 15.0% Upland cottonseed as whole, cracked, roasted, cracked-roasted, or extruded. Analysis of the seed revealed that roasting or extrusion markedly reduced free gossypol (FG) content. Minor effects on animal performance were observed, but plasma TG decreased with roasting or extrusion of seeds, with the greatest reduction when the seed was cracked and then roasted. In experiment 3, steers were fed 2 levels of WCS (7.0 or 14.0% of DM) with 3 levels of cottonseed meal (2.8, 5.5, or 8.5% of DM) in the diet. Animal performance was not altered by diet, but plasma gossypol concentrations and responses were greater in steers fed diets with more WCS, because of the greater FG intake. In experiment 4, 24 steers were fed diets with 15.0% cottonseed (Upland or Pima) either as whole or cracked. Pima cottonseed increased TG and FG intakes, which resulted in greater plasma TG concentration and response. Animal response to processing of cottonseed tended to differ according to type of cottonseed. However, feeding Pima and cracking of cottonseed increased gossypol availability and plasma TG concentrations.


Asunto(s)
Bovinos/sangre , Aceite de Semillas de Algodón , Dieta , Gosipol/administración & dosificación , Gosipol/sangre , Hierro de la Dieta/administración & dosificación , Animales , Disponibilidad Biológica , Suplementos Dietéticos , Manipulación de Alimentos , Gosipol/farmacocinética , Masculino , Tamaño de la Partícula , Análisis de Regresión , Aumento de Peso
2.
J Am Med Inform Assoc ; 2(5): 295-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7496878

RESUMEN

The Active Digital Library at the Vanderbilt University Medical Center has created and implemented an educational software evaluation process to facilitate the timely recommendation for product acquisition. Using this process, breadth and depth of subject coverage, clarity of presentation, quality of construction, and ease of use are being assessed by content and technical experts. The process uses a team approach, employing a bi-level evaluation instrument based on existing software evaluation forms and system bug reports.


Asunto(s)
Instrucción por Computador , Bibliotecas Médicas , Desarrollo de la Colección de Bibliotecas , Validación de Programas de Computación , Educación Médica , Control de Formularios y Registros , Humanos , Automatización de Bibliotecas
3.
J Am Med Inform Assoc ; 1(5): 395-403, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-7850563

RESUMEN

OBJECTIVE: To examine the information needs of health care professionals in HIV-related clinical encounters, and to determine the suitability of existing information sources to address those needs. SETTING: HIV outpatient clinic. PARTICIPANTS: Seven health care professionals with diverse training and patient care involvement. METHODS: Based on patient charts describing 120 patient encounters, participants generated 266 clinical questions. Printed and on-line information sources were used to answer questions in two phases: using commonly available sources and using all available medical library sources. MEASUREMENTS: The questions were divided into 16 categories by subject. The number of questions answered, their categories, the information source(s) providing answers, and the time required to answer questions were recorded for each phase. RESULTS: Each participant generated an average of 3.8 clinical questions per chart. Five categories accounted for almost 75% of all questions; the treatment protocols/regimens category was most frequent (24%). A total of 245 questions (92%) were answered, requiring an average of 15 minutes per question. Most (87%) of the questions were answered via electronic sources, even though paper sources were consulted first. CONCLUSIONS: The participating professionals showed considerable information needs. A combination of on-line and paper sources was necessary to provide the answers. The study suggests that present-day information sources are not entirely satisfactory for answering clinical questions generated by examining charts of HIV-infected patients.


Asunto(s)
Atención Ambulatoria/organización & administración , Infecciones por VIH , Personal de Salud , Sistemas de Información/normas , Bases de Datos Bibliográficas , Bases de Datos Factuales , Humanos , Sistemas de Registros Médicos Computarizados , Encuestas y Cuestionarios
4.
J Am Med Inform Assoc ; 4(1): 57-67, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-8988475

RESUMEN

OBJECTIVE: Refine the understanding of the desirable skills for health sciences librarians as a basis for developing a training program model that reflects the fundamental changes in health care delivery and information technology. DESIGN: A four-step needs assessment process: focus groups developed lists of desirable skills; the research team organized candidate skills into a taxonomy; a survey of a random sample of librarians and library users assessed perception of importance of individual skills; and the research team framed, as a unifying hypothesis, a training model. SURVEY METHODS: The survey was distributed to random samples of 150 librarians, stratified by type of library, and 150 library users, stratified by type of use. A non-randomized sample was obtained by mounting the survey on a World Wide Web server. The survey instrument included 96 distinct skills organized into 13 categories. Respondents rated the importance of each skill on a Likert scale and provided a separate ranking by identifying the ten most important skills for the profession. RESULTS: Among the participants, 51% of librarians and 36% of library users responded to the survey. All categories of skills were rated above the midpoint of priority on the Likert scale. All groups rated personality characteristics and skills as most important, with an understanding of the health sciences, education, and research being rated comparably to technical skills. CONCLUSIONS: Health sciences librarians need a new educational model that provides them with broad-based tools to discover new roles and new resources for acquiring individual skills as the need arises. A unifying training model would involve trainees in developing their learning plan in a way that promotes proactive inquiry and self-directed learning, and it would rotate the trainees through projects to provide skills and an understanding of end-user work processes.


Asunto(s)
Bibliotecas Médicas/organización & administración , Bibliotecología/educación , Informática Médica/educación , Modelos Educacionales , Desarrollo de Personal/métodos , Curriculum , Recolección de Datos , Evaluación Educacional , Grupos Focales , Humanos , Internado no Médico , Objetivos Organizacionales , Análisis y Desempeño de Tareas , Enseñanza/métodos , Estados Unidos
5.
Theriogenology ; 29(5): 1027-35, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-16726424

RESUMEN

The influence of temporary cooling on pregnancy rate and ovarian secretion of cortisol, estradiol and progesterone in Holstein cows was evaluated during the months of June to September. Cows were randomly assigned to one of five treatment groups: 1) evaporative cooling, 8 d; 2) evaporative cooling, 16 d; 3) refrigerated air conditioning, 8 d; 4) refrigerated air conditioning, 16 d and 5) controls maintained outdoors with access to shade. Estrus was synchronized by giving two injections of prostaglandin (25 mg). Cows in the cooled groups were placed in box stalls at the time of the second prostaglandin injection, allowing them to be cooled for approximately 3 d prior to breeding. Blood samples were taken on days 0, 5, 10, 15, 20 and 25 postbreeding and serum was analyzed for estradiol, cortisol, progesterone and a pregnancy-specific protein. Pregnancy rates as determined by palpation per rectum at 40 to 60 d post breeding were not different between cows in cooled treatments, regardless of duration or type of cooling. Pregnancy rate was higher (P<0.05) in cooled as compared to control cows. Serum progesterone concentrations were higher on Day 15 in cooled cows as compared to control cows. No differences in serum estradiol or cortisol concentrations were observed between cooled and control cows. Pregnancy-specific protein determinations indicated that 50% of both cooled and control cows conceived. Results indicate that temporary cooling increased pregnancy rates by increasing embryonic survival rates.

6.
J Anim Sci ; 51(6): 1387-92, 1980 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7204280

RESUMEN

Chopped whole corn plant was treated before ensiling with 1.4% ammonia (of dry matter) to which .36% atom excess of 15N had been added. About 50 kg of material (14 kg dry matter) were placed in .5-mm polyethylene bags (of double thickness) which were evacuated and served as experimental silos. Silage samples were taken on days 0, 3, 7, 14, 21 and 50 and analyzed for N fractions. The 15N content of these fractions was analyzed by a mass spectrophotometer. N fractions of untreated silage were also determined. Between days 0 and 7 of fermentation, ammonia N decreased from 50 to 39% of the total silage N, with a corresponding increase in nonammonia N, from 50 to 60%. Thereafter, little change was noted in these fractions. Approximately 40% of the increase in non-ammonia N was in the soluble portion and 60% was in the insoluble portion. Insoluble N of treated silage was 50% higher than that of control silage. Initially, 89% of the N from added ammonia was recovered as ammonia, but this proportion decreased to 68% by day 7 and changed little thereafter. There was immediate incorporation of 43% of the ammonia into the insoluble N fraction. Most of the initial binding was as intact ammonia, with a subsequent release during fermentation. Because direct ammonia incorporation accounted for a higher percentage of the insoluble N increase on day 0 than on subsequent days, these data support earlier studies which showed that ammonia decreased breakdown of protein of the ensiled corn plant.


Asunto(s)
Amoníaco/farmacología , Alimentación Animal , Nitrógeno/metabolismo , Ensilaje , Fermentación , Zea mays
7.
J Anim Sci ; 58(2): 452-9, 1984 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6706877

RESUMEN

Two experiments using six rumen-fistulated Holstein steers in 3 X 3 Latin square designs were conducted to test the effects of urea addition to corn silage, and grain addition to haylage, on feed intake, digestibility of nutrients and rumen fermentation of complete diets fed once daily. Addition of .34 and .68% urea to corn silage increased dietary crude protein from 8.1 to 11.3 and 13.3%, and stimulated dry matter intake 6 and 13%. No change in dry matter or acid-detergent fiber digestibility was noted among treatments. Rumen contents, sampled at 2 h intervals for 24 h postfeeding, exhibited two distinct peaks in ammonia (NH3) concentration at 2 and 12 h. Rumen pH decreased through 12 h and then increased. Total VFA increased from 7 to 11 mmol/dl between 0 and 14 h and then decreased. Individual VFA's followed a similar pattern. Added nitrogen (N) increased (P less than .05) concentrations of acetic, butyric and total VFA. Little difference in molar percentages of VFA was noted among treatments and sampling times, suggesting that N stimulated the amount of VFA produced rather than the type of rumen fermentation. Addition of corn to alfalfa haylage diets at 30 and 60% of dry matter (DM) stimulated dry matter intakes 19 and 38%, respectively, and increased DM, N and acid-detergent fiber (ADF) digestibilities about 8%. However, total ADF disappearance from the digestive tract was 25% lower on 60% corn, compared with 0 and 30%.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Bovinos/metabolismo , Proteínas en la Dieta/administración & dosificación , Metabolismo Energético , Rumen/metabolismo , Amoníaco/metabolismo , Animales , Ácidos Grasos Volátiles/biosíntesis , Fermentación , Concentración de Iones de Hidrógeno , Masculino , Medicago sativa , Ensilaje , Urea/administración & dosificación , Zea mays
8.
J Anim Sci ; 72(4): 1038-42, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8014138

RESUMEN

Two trials were conducted to determine the influence of yucca extract on ruminal digestion, fermentation, and ammonia patterns using ruminally and duodenally cannulated dairy cows. In Trial 1, urea at 0 or 1% of the diet and yucca extract at 0 or 4 g/d formed four dietary treatments in a 2 x 2 factorial arrangement. The experimental design was a 4 x 4 Latin square with 15-d periods. Duodenal digesta were sampled every 6 h during the last 4 d of each period to determine OM and ADF digestibilities and bacterial protein synthesis in the rumen using Cr2O3 and 15N markers. Ruminal digestibilities were (percentage): OM 46.3 vs 43.0%, and ADF 35.9 vs 41.4%, with or without Deodorase. Microbial protein entering the duodenum averaged 2.7 vs 3.1 kg/d for the respective treatments. Ruminal measurements were not affected by treatment (P > .10). In Trial 2, five cows were used in a 5 x 5 Latin square with 7-d periods. Treatments were 0, 2, 4, 6, and 8 g/d of yucca extract administered via ruminal cannulas. Ruminal fluid was sampled 0, 1, 2, 4, 7, 11, 16, and 22 h after feeding during the last 2 d of each period. Average ruminal NH3 N ranged from 31.4 to 35.4 mg/dL, pH 5.99 to 6.18, and total VFA from 120 to 129 mM, and all did not differ among treatments (P > .10). Yucca extract administered at 4 g/d did not significantly affect ruminal digestibilities of OM and ADF, and up to 8 g/d did not affect ruminal NH3, pH, or VFA.


Asunto(s)
Bovinos/metabolismo , Lactancia/metabolismo , Extractos Vegetales/farmacología , Rumen/metabolismo , Amoníaco/análisis , Animales , Proteínas Bacterianas/biosíntesis , Bovinos/fisiología , Digestión/efectos de los fármacos , Femenino , Plantas Comestibles , Rumen/efectos de los fármacos , Rumen/microbiología , Espirostanos/farmacología
9.
J Anim Sci ; 80(2): 525-32, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11881937

RESUMEN

Our objectives were to determine effects of grain processing on splanchnic (gut tissues and liver) N metabolism and whole-body N balance by growing steers and to ascertain the relative contributions of ruminal and intestinal tissues to net absorption and utilization of N-containing nutrients. Seven beef steers (348 kg initial BW), surgically implanted with appropriate catheters, were fed diets containing 77% steam-flaked (SF) or dry-rolled (DR) sorghum grain. Blood flows and net output or uptake of ammonia N, urea N, and alpha-amino N (estimate of amino acids) were measured across portal-drained viscera (PDV or gut tissues) and intestinal, ruminal, hepatic, and splanchnic tissues (PDV + hepatic). The experimental design was a crossover between DR and SF diets, with six samplings of blood at 2-h intervals on 2 d for each steer. Nitrogen intake (139 +/- 3 g/d), output in urine (43 +/- 2 g/d), and retention (40 +/- 3 g/d) were similar for both processing treatments. When steers were fed SF sorghum compared to DR sorghum, N retention as a percentage of N intake was numerically greater (P < 0.12), output of fecal N was numerically lower (P < 0.13), and urinary urea N was lower (P < 0.04). For SF vs DR, net uptake of alpha-amino N by liver was higher (P < 0.04; 20 vs 9 g/d) and was numerically lower (P < 0.16) for ruminal tissues (15 vs 33 g/d). Feeding steers SF compared to DR tended to increase net transfer (cycling) of blood urea N to PDV (57 vs 41 g/d; P < 0.07), increased cycling to intestinal tissues (15 vs 6 g/d; P < 0.05), and numerically increased transfer to ruminal tissues (42 vs 32 g/d; P < 0.12) but did not alter other net output or uptake of N across splanchnic tissues. Total urea N transfer (blood + saliva) was similar for both treatments. Net uptake of alpha-amino N by ruminal tissues was about 30% of the net amount of alpha-amino N absorbed across the intestinal tissues. In summary, most of the blood urea N cycled from the liver to gut tissues was transferred to ruminal tissues for potential microbial protein synthesis, and the net ruminal utilization of alpha-amino N was about 30% of that absorbed from intestinal tissues. Feeding growing steers SF compared to DR sorghum diets numerically increased whole-body N retention (percentage of N intake) by about 15% and tended to increase transfer of blood urea N to the gut by about 40%, which could increase the supply of high-quality microbial protein for absorption.


Asunto(s)
Bovinos/metabolismo , Dieta/veterinaria , Mucosa Intestinal/metabolismo , Hígado/metabolismo , Nitrógeno/metabolismo , Rumen/metabolismo , Absorción , Aminoácidos/metabolismo , Amoníaco/metabolismo , Animales , Animales Recién Nacidos , Nitrógeno de la Urea Sanguínea , Bovinos/crecimiento & desarrollo , Estudios Cruzados , Grano Comestible/metabolismo , Heces/química , Manipulación de Alimentos/métodos , Masculino , Nitrógeno/sangre , Distribución Aleatoria , Circulación Esplácnica , Urea/metabolismo
10.
J Anim Sci ; 69(4): 1733-40, 1991 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-2071528

RESUMEN

Trials were conducted to evaluate effects of a fermentation extract of Aspergillus oryzae (AO) on milk production and composition, diet digestibility, and rectal temperature changes in lactating dairy cows. Treatments were incorporated as a top dressing at the morning feeding and consisted of control (90 g/d of ground sorghum) or AO (3 g of culture + 87 g of ground sorghum daily). Twenty-four mid-lactation Holstein cows were paired for production in Lactation Trial 1 (LT-1). In Lactation Trial 2 (LT-2), 46 cows (20 primiparous and 26 multiparous) in early lactation were used. Trials lasted 12 wk. In LT-1, AO supplementation increased milk yields only at 2 (P less than .05) and 8 wk (P less than .10) of treatment. Rectal temperatures were lower (P less than .05) for cows fed AO for 4 of 10 readings made during summer. Supplementation of AO culture in LT-2 (early lactation cows) increased milk production and feed efficiency (P less than .05). Inner ear temperatures tended to be lower (P less than .11) for cows fed AO. Digestion trials, conducted at the end of lactation trials, used Cr2O3 as an indigestible marker. In Digestion Trial 1, digestibilities were not significantly (P greater than .10) affected by AO supplementation. However, in Digestion Trial 2, AO increased (P less than .05) digestibilities of DM, OM, CP, NDF, and ADF. Length and number of meals were not affected (P greater than .10) by feeding AO. In summary, milk yields, efficiency of milk production, and nutrient digestibilities were higher for early lactation cows fed a high-concentrate diet supplemented with 3 g of AO/d. Mid-lactation cows fed a lower-energy diet were less responsive to AO than early lactation cows, though similar trends were shown.


Asunto(s)
Aspergillus oryzae/metabolismo , Temperatura Corporal , Bovinos/microbiología , Ingestión de Alimentos , Lactancia , Análisis de Varianza , Animales , Bovinos/metabolismo , Bovinos/fisiología , Femenino , Fermentación , Leche/química , Leche/metabolismo , Aumento de Peso
11.
J Anim Sci ; 71(11): 2837-42, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8270505

RESUMEN

Thirty-two Holstein cows averaging 70 d postpartum were used to compare digestibility of whole short staple cottonseed (SS) to whole Pima (WP), coarsely cracked Pima (CrP), and ground Pima (GP) cottonseeds and their effects on lactational performance. Cottonseed was fed at 15% of diet DM. Milk and solids-corrected milk (SCM) yields were higher for cows fed GP than for cows fed CrP or WP but were not different from yields of cows fed SS. Feed efficiency (SCM/DMI) was higher for cows fed GP and SS than for those fed WP. Milk of cows fed GP was lower in stearic acid but higher in linoleic and linolenic acids than milk of cows fed SS. Whole seeds passing into the feces (percentage of consumed) were higher for WP (12.3%) than for SS (6.2%). Total tract digestibility of ether extract was lower for WP than for other diets. Digestibilities of other nutrients were not different. To test storage characteristics, samples of cottonseed were incubated at 32 degrees C and 30% relative humidity for 0, 10, 20, and 30 d, or stored at ambient temperatures in covered buckets for 9 mo. No differences in amount of free fatty acids between incubated samples were noted, and only CrP stored in buckets for 9 mo was significantly higher in free fatty acids than initial or frozen seed. No differences in aflatoxin were detected, and levels were very low. Milk yield of cows fed GP diets was similar to that of cows fed SS diets and slightly higher than those of cows fed CrP or WP diets. Processing the Pima seed increased feed efficiency.


Asunto(s)
Alimentación Animal , Bovinos/fisiología , Aceite de Semillas de Algodón/metabolismo , Digestión , Lactancia/fisiología , Alimentación Animal/normas , Animales , Aceite de Semillas de Algodón/química , Fibras de la Dieta/análisis , Ácidos Grasos/análisis , Femenino , Leche/química , Leche/metabolismo , Valor Nutritivo , Distribución Aleatoria
12.
J Anim Sci ; 71(11): 3073-7, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8270530

RESUMEN

Stable 15N isotope was used to determine the extent of microbial colonization of in situ incubation residues and the influence of colonization on estimates of ruminal degradability of feed N. In an in vitro trial, 15N:total N ratio remained unchanged after the soluble (by water, saline, or buffer solution) fraction of plant N was removed, suggesting that 15N was uniformly distributed in the soluble and insoluble N fractions. In three in situ trials, corn grain, corn husks, and alfalfa hay labeled with 15N as an internal marker were incubated in Dacron bags in the rumen of two lactating Holstein cows for 3, 6, 12, 24, 36, and 48 h. Enrichment of 15N in samples decreased with increased time of incubation for all feeds. At 48 h of incubation, 31, 71, and 65% of the residual N was microbial N for corn grain, corn husks, and alfalfa hay, respectively. Bacterial cell DM, as a percentage of residual DM, increased in a quartic manner, suggesting that microbial colonization depended on substrate availability. For 24, 36, and 48 h incubation, bacterial DM, as a percentage of total residue, averaged 10.0 +/- 1.0% for corn grain, 17.5 +/- 1.4% for corn husks, and 22.0 +/- .2% for alfalfa hay. Apparent degradability of N after 48 h of incubation was approximately 65% for corn grain and alfalfa hay and 19% for corn husks. When corrected for bacterial N, degradabilities of N in all feeds increased and the degradabilities for corn husks became similar to those for corn grain.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alimentación Animal/microbiología , Bovinos/metabolismo , Microbiología de Alimentos , Nitrógeno/metabolismo , Rumen/metabolismo , Animales , Bacterias/metabolismo , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Femenino , Fermentación , Medicago sativa , Zea mays
13.
J Anim Sci ; 75(6): 1681-5, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9250533

RESUMEN

To examine the effects of various densities of sorghum grain resulting in graded levels of ruminally degradable starch on lactational performance, 32 lactating Holstein cows (90 d in milk [DIM]) were assigned to four treatments for 58 d. Diets contained 37% alfalfa hay, 3% cottonseed hulls, 10% whole cottonseed, 6% soybean meal, 5% of a molasses-mineral-vitamin supplement, and 39% sorghum grain. Treatments were dry-rolled sorghum (DRS) at 643 g/L or stream-flaked sorghum (SF) at 437, 360, and 283 g/L. Dry matter intake was highest for DRS followed by SF360, with the linear (P < .01) and cubic (P < .05) effects significant. The linear decrease in milk (P < .05) and 3.5% fat corrected milk (FCM, P < .025) with decreased density of sorghum was because of large decreases on SF283. Steam-flaking increased total tract digestibilities of DM, OM, CP, starch, and ADF when compared with dry-rolling. Efficiency of conversion of feed DM to FCM and feed CP to milk protein were greater for sorghum flaked at 437 and 360 g/L than for DRS or the 283 g/L flake. The 283 g/L flake decreased DMI, milk yield, and milk fat percentage. Addition of buffer (1% NaHCO3) tended to ameliorate the decrease in DMI. These data show greater efficiency of feed utilization and conversion of feed CP to milk protein in cows fed sorghum grain flaked at 437 and 360 g/L compared with those fed dry-rolled sorghum or that flaked at 283 g/L.


Asunto(s)
Bovinos/fisiología , Grano Comestible/normas , Lactancia/fisiología , Animales , Bovinos/metabolismo , Aceite de Semillas de Algodón/química , Aceite de Semillas de Algodón/normas , Carbohidratos de la Dieta/análisis , Carbohidratos de la Dieta/metabolismo , Carbohidratos de la Dieta/farmacología , Proteínas en la Dieta/análisis , Proteínas en la Dieta/metabolismo , Proteínas en la Dieta/farmacología , Grano Comestible/química , Femenino , Manipulación de Alimentos , Lactancia/efectos de los fármacos , Medicago sativa/química , Medicago sativa/normas , Leche/metabolismo , Distribución Aleatoria , Glycine max/química , Glycine max/normas , Almidón/análisis , Almidón/metabolismo , Almidón/farmacología
14.
J Anim Sci ; 78(5): 1355-63, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10834592

RESUMEN

The objective of this study was to determine effects of processing method, dry-rolled (DR) vs steam-flaked (SF), and degree of processing (flake density, FD) of SF sorghum grain on splanchnic (gut and liver) N metabolism by growing steers. Diets contained 77% sorghum grain either DR or SF at densities of 437, 360, and 283 g/L (SF34, SF28, and SF22, respectively). Eight crossbred steers (340 kg initial BW), implanted with indwelling catheters into portal, hepatic, and mesenteric veins and the mesenteric artery, were used in a randomized complete block design. Blood flows and net output or uptake of ammonia N, urea N (UN), and alpha-amino N (AAN) were measured across portal-drained viscera, hepatic, and splanchnic tissues. Plasma arterial, portal, and hepatic concentrations of individual amino acids were also measured. Decreasing FD linearly increased (P = .04) net absorption of AAN (51, 73, and 78 g/d for SF34, SF28, and SF22, respectively) and transfer (cycling) of blood UN to the gut (49, 48 and 64 g/d; P = .02). Net UN cycling averaged 38% of N intake across all diets. Hepatic uptake of AAN or UN synthesis, and splanchnic output of AAN and UN, were not altered by FD. Lowering FD linearly increased (P < or = .02) portal-arterial concentration differences for blood AAN and UN and plasma arterial concentrations for alanine. Steers fed SF compared to DR tended to have greater (P = .11) blood UN cycling (percentage of hepatic synthesis; 64 vs 50%) and decreased (P = .03) net splanchnic UN output (30 vs 50 g/d), but other net fluxes of N were not altered across splanchnic tissues. Steam-flaking compared to dry-rolling tended to decrease (P = .12) portal, but not hepatic, blood flow and increased (P < .01) hepatic-arterial concentration differences for blood UN. Except for a decrease (P = .01) in hepatic-arterial concentration differences of glutamine, plasma amino acid concentrations were not altered by feeding SF vs DR sorghum. Processing method (steam-flaking vs dry-rolling) or increasing the degree of processing (by decreasing FD) of SF sorghum grain resulted in greater transfer of blood UN to the gut. Reducing FD also linearly increased the absorption of AAN by growing steers, which explains (in part) published responses of superior performance by steers fed SF grains.


Asunto(s)
Bovinos/crecimiento & desarrollo , Dieta , Grano Comestible , Nitrógeno/sangre , Circulación Esplácnica , Animales , Nitrógeno de la Urea Sanguínea , Bovinos/sangre , Digestión , Ingestión de Energía , Absorción Intestinal , Masculino , Nitrógeno/metabolismo
15.
J Anim Sci ; 78(5): 1364-71, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10834593

RESUMEN

We determined the effect of processing method (dry-rolled [DR] vs steam-flaked [SF]) and degree of processing (flake density; FD) of SF sorghum grain on splanchnic (gut and liver) metabolism of energy-yielding nutrients by growing steers. Diets contained 77% sorghum grain, either DR or SF, with SF at densities of 437, 360, or 283 g/L (SF34, SF28, or SF22). Eight multicatheterized steers (340 kg initial BW) were used in a randomized complete block design. Net output or uptake of glucose, L-lactate, VFA, and beta-hydroxybutyrate (BHBA) were measured across portal-drained viscera (PDV), liver, and splanchnic (PDV plus liver) tissues. Net absorption of glucose across PDV was negative and similar for all treatments (average of -104 g/d). Decreasing FD of SF sorghum grain linearly increased (P < or = .04) net absorption and splanchnic output of L-lactate by 20 and 130%, respectively, and hepatic synthesis (P = .06) and splanchnic output (P = .01) of glucose by 50%. Reducing FD did not alter output or uptake of acetate or n-butyrate by gut and liver tissues, but linearly decreased (P = .06) splanchnic output of BHBA by 40%. Net absorption (P = .18) and splanchnic output (P = .15) of propionate tended to be increased linearly by 50% with decreasing FD. Neither processing method (SF vs DR) nor degree of processing (varying FD) altered hepatic nutrient extraction ratios or estimated net absorption and splanchnic output of energy. Maximal contribution of propionate, L-lactate, and amino acids (alpha-amino N) to gluconeogenesis averaged 49, 11, and 20%, respectively. Feeding steers SF compared to DR diets did not alter net output or uptake of energy-yielding nutrients across splanchnic tissues, except net absorption of acetate tended to be greater (P = .13) for steers fed DR. Increasing degree of grain processing in the present study, by incrementally decreasing FD, tended to linearly increase the net absorption of glucose precursors (propionate and lactate), resulting in linear increases in synthesis and output of glucose by the liver to extrasplanchnic tissues (e.g., muscle).


Asunto(s)
Alimentación Animal , Bovinos/metabolismo , Grano Comestible/metabolismo , Ácidos Grasos Volátiles/farmacocinética , Glucosa/farmacocinética , Ácido Láctico/farmacocinética , Hígado/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Animales , Carbohidratos de la Dieta/metabolismo , Digestión , Gluconeogénesis , Hidrólisis , Masculino
16.
J Anim Sci ; 77(10): 2824-31, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10521046

RESUMEN

Crossbred steers (n = 7; 400 kg BW), fitted with T-type cannulas in the duodenum and ileum, were used to examine the effects of processing method, dry-rolled (DR) vs. steam-flaked (SF) sorghum grain, and degree of processing (flake density; FD) of SF corn (SFC) and SF sorghum (SFS) grain on site and extent of DM, starch, and N digestibilities and to measure extent of microbial N flow to the duodenum. In Exp. 1, diets contained 77% DRS or 77% SFS with FD of 437, 360, and 283 g/L (SF34, SF28, and SF22). In Exp. 2, diets contained 77% SFC with FD of SF34 or SF22. For sorghum and corn diets, respective average daily intakes were as follows: DM, 6.7 and 8.1 kg; starch, 3.8 and 4.7 kg; N, 136 and 149 g. Steers fed SFS vs. DRS increased (P = .01) starch digestibilities (percentage of intake) in the rumen (82 vs. 67%) and total tract (98.9 vs. 96.5%) and decreased digestibilities in the small intestine (16 vs. 28%; P = .01) and large intestine (.5 vs 1.2%; P = .05). As a percentage of starch entering the segment, digestibility was increased (P = .01) within the small intestine (91 vs. 85%) but was not altered within the large intestine by steers fed SFS vs. DRS. Decreasing FD of SFS and of SFC, respectively, linearly increased starch digestibilities (percentage of intake) in the rumen (P = .03, .02) and total tract (P = .03, .09) and linearly diminished starch digestibilities in the small intestine (P = .04, .09). Starch digestibilities (percentage of entry) within the small or large intestine were not changed by FD. The percentage of dietary corn or sorghum starch digested in the large intestine was very small, less than 2% of intake. Microbial N flow to the duodenum was not altered by SFS compared to DRS, or by decreasing FD of SFS and SFC. Reducing FD of SFS, but not of SFC, tended to decrease (P = .07) microbial efficiency linearly and tended to increase (P = .06) total tract N digestibilities linearly. Steam flaking compared to dry rolling of sorghum grain and decreasing FD of SFC and SFS grain consistently increased starch digestibility in the rumen and total tract of growing steers. The greatest total digestibility of dietary starch occurred when the proportion digested in the rumen was maximized and the fraction digested in the small intestine was minimized. These changes in sites of digestion account, in part, for the improved N conservation and greater hepatic output of glucose by steers fed lower FD of SFS reported in our companion papers.


Asunto(s)
Bovinos/metabolismo , Carbohidratos de la Dieta/metabolismo , Digestión , Grano Comestible/metabolismo , Intestino Delgado/metabolismo , Rumen/metabolismo , Ensilaje , Almidón/metabolismo , Animales , Zea mays/metabolismo
17.
Nurs Manage ; 26(7): 36-7, 41, 42, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7603672

RESUMEN

Electronic information networks are explored in terms of the political and economic impact of such concepts as the National Information Infrastructure. The relevancy of electronic information retrieval to nursing is discussed as it applies to current health-care information management. Electronic information sources applicable to nursing are described along with examples of how they may be utilized. Network functions, such as bulletin boards, Freenets and literature searches, are explained and the implications for evolution of health-care delivery are summarized.


Asunto(s)
Comunicación , Redes de Comunicación de Computadores , Almacenamiento y Recuperación de la Información , Enfermería , Sistemas en Línea , Humanos
18.
Mol Ecol Resour ; 13(2): 168-76, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23228011

RESUMEN

Microgastrine wasps are among the most species-rich and numerous parasitoids of caterpillars (Lepidoptera). They are often host-specific and thus are extensively used in biological control efforts and figure prominently in trophic webs. However, their extraordinary diversity coupled with the occurrence of many cryptic species produces a significant taxonomic impediment. We present and release the results of 8 years (2004-2011) of DNA barcoding microgastrine wasps. Currently they are the best represented group of parasitoid Hymenoptera in the Barcode of Life Data System (BOLD), a massive barcode storage and analysis data management site for the International Barcoding of Life (iBOL) program. There are records from more than 20 000 specimens from 75 countries, including 50 genera (90% of the known total) and more than 1700 species (as indicated by Barcode Index Numbers and 2% MOTU). We briefly discuss the importance of this DNA data set and its collateral information for future research in: (1) discovery of cryptic species and description of new taxa; (2) estimating species numbers in biodiversity inventories; (3) clarification of generic boundaries; (4) biological control programmes; (5) molecular studies of host-parasitoid biology and ecology; (6) evaluation of shifts in species distribution and phenology; and (7) fostering collaboration at national, regional and world levels. The integration of DNA barcoding with traditional morphology-based taxonomy, host records, and other data has substantially improved the accuracy of microgastrine wasp identifications and will significantly accelerate further studies on this group of parasitoids.


Asunto(s)
Código de Barras del ADN Taxonómico , Filogenia , Avispas/clasificación , Avispas/genética , Animales , Secuencia de Bases , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
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