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1.
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
2.
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
3.
J Dairy Sci ; 87(8): 2506-18, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15328274

RESUMEN

Effects of varying amounts of gossypol from whole Upland cottonseed (WCS) and cottonseed meal (CSM) were evaluated in 40 midlactation Holstein cows. After 14 d of pretreatment, cows were assigned to 1 of the 5 treatments for 84 d: control (no gossypol), 931 mg/kg total gossypol (TG) and 850 mg/kg free gossypol (FG) from WCS (moderate TG and high FG); 924 mg/kg TG and 91 mg/kg FG from CSM (moderate TG and low FG), 945 mg/kg TG and 479 mg/kg FG with equal amounts of TG from WCS and CSM (moderate TG and FG), or 1894 mg/kg TG and 960 mg/kg FG with equal amounts of TG from WCS and CSM (high TG and FG). Concentrations of plasma gossypol (PG) and its isomers were directly proportional to FG intake. Concentrations of PG reached a plateau after 28 d on treatment, and they were highest in cows receiving a diet with high TG and FG. Erythrocyte fragility differed among treatments and increased with increasing FG intake. Plasma gossypol returned to negligible concentrations 28 d after withdrawal of cottonseed products from the high TG and FG diet. Serum vitamin A was similar among treatments, but vitamin E increased with increasing FG intake. Serum enzymes were generally unaffected by treatments, but urea N increased in diets higher in TG and FG. Intake of dry matter was higher for the diet high in TG and FG than for the control diet, but was similar for other treatments. Cows receiving the high TG and FG diet produced more milk and 3.5% fat-corrected milk, with no changes in milk composition. Feeding a diet containing 1894 mg/kg TG and 960 mg/kg FG for 84 d increased PG concentrations and erythrocyte fragility and resulted in minor changes in blood metabolites and enzymes, but no detrimental effect on lactation performance was observed. Indicators of liver, kidney, and muscle cell viability suggest that the higher amounts of gossypol consumed in this study had only minor effects on those tissues in lactating dairy cows.


Asunto(s)
Bovinos/sangre , Aceite de Semillas de Algodón/química , Dieta , Gosipol/administración & dosificación , Lactancia/efectos de los fármacos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Temperatura Corporal , Bovinos/fisiología , Enzimas/sangre , Femenino , Gosipol/sangre , Cinética , Leche/química , Fragilidad Osmótica/efectos de los fármacos , Respiración , Vitamina A/sangre , Vitamina E/sangre
4.
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
5.
J Dairy Sci ; 85(1): 148-59, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11862966

RESUMEN

Objectives were to determine net release or uptake of alpha-amino N, ammonia N, and urea N across portal-drained viscera, liver, splanchnic, and mammary tissues of lactating Holstein cows (n = 8, 86 +/- 8 d in milk) fed alfalfa hay-based total mixed rations containing 40% dry-rolled or steam-flaked sorghum grain. The total mixed rations were offered at 12-h intervals in a crossover design. Blood samples were obtained from indwelling catheters in the portal, hepatic, and mammary veins and mesenteric or costoabdominal arteries, every 2 h for each cow and diet. Steam-flaking increased in vitro rate of starch hydrolysis compared with dry-rolled sorghum (66 vs. 25%). Diet did not alter dry matter intake (18.2 +/- 0.3 kg). Daily milk yield (27.6 +/- 0.8 kg), efficiency of production, and most milk components did not differ between diets, but fat yield was reduced (0.86 vs. 0.91 kg/d) by steam-flaked sorghum, and lactose concentration was increased (4.99 vs. 4.82%). Blood flows in portal and hepatic veins did not differ between diets. Steam-flaking tended to increase urea N cycling to the gut (162 vs. 95 g/d) compared with dry-rolling of sorghum, whereas net absorption of ammonia N and alpha-amino N across portal-drained viscera were decreased. Net mammary uptake of a-amino N increased more than 20% (83 vs. 67 g/d), resulting in a higher mammary extraction ratio (15 vs. 11%) for steam-flaked versus dry-rolled sorghum. Flaking of sorghum improved the efficiency of postabsorptive N metabolism by increasing urea N cycled to the gut and alpha-amino N uptake by the mammary gland.


Asunto(s)
Alimentación Animal/clasificación , Bovinos/fisiología , Lactancia/fisiología , Leche/metabolismo , Nitrógeno/metabolismo , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Nitrógeno de la Urea Sanguínea , Bovinos/metabolismo , Estudios Cruzados , Dieta/veterinaria , Ingestión de Alimentos/fisiología , Grano Comestible , Femenino , Manipulación de Alimentos/métodos , Absorción Intestinal , Lactancia/metabolismo , Lactosa/análisis , Lípidos/análisis , Hígado/irrigación sanguínea , Hígado/metabolismo , Glándulas Mamarias Animales/irrigación sanguínea , Glándulas Mamarias Animales/metabolismo , Leche/química , Sistema Porta/fisiología , Distribución Aleatoria , Circulación Esplácnica
6.
J Dairy Sci ; 85(1): 160-8, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11862967

RESUMEN

Objectives were to determine net release or uptake of a-amino N, ammonia N, and urea N across portal-drained viscera, liver, splanchnic, and mammary tissues of lactating Holstein cows (n = 6; 109 +/- 9 d in milk) fed alfalfa hay-based total mixed rations (TMR) containing 40% steam-rolled or steam-flaked corn grain. The TMR were offered at 12-h intervals in a crossover design. Blood samples were obtained from indwelling catheters in portal, hepatic, and mammary veins and mesenteric or costo abdominal arteries, every 2 h for each cow and diet. Steam-flaked compared with steam-rolled corn greatly increased in vitro starch hydrolysis (56 vs. 34%). Daily intake of dry matter (18.4 +/- 0.4 kg/d), starch, N, and net energy for lactation by cows were not altered by processing corn; neither were daily yield of milk (29.1 +/- 0.7 kg/d), fat-corrected milk, nor fat-corrected milk per dry matter intake. Steam-flaking tended to increase percent milk protein (2.97 vs. 2.82%; P = 0.07), but not yield, and decrease percent lactose (4.83 vs. 4.94) but not yield. Portal and hepatic blood flows were not affected by diet, nor were net absorption of alpha-amino N and ammonia N. Steam-flaking compared with steam-rolling increased urea N cycling to portal-drained viscera (212 vs. 87 g/d) by 140%, estimated mammary uptake and extraction ratio of alpha-amino N. Flaking versus rolling of corn improved N utilization in dairy cows by increasing urea cycling to the gut and uptake of a-amino N by the mammary gland. Higher mammary uptake of alpha-amino N (78 vs. 50 g/d) by dairy cows fed steam-flaked corn tended to increase milk protein content and may explain the previously observed effects of cows fed steam-flaked versus steam-rolled corn.


Asunto(s)
Alimentación Animal/clasificación , Bovinos/fisiología , Lactancia/fisiología , Nitrógeno/metabolismo , Zea mays , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Nitrógeno de la Urea Sanguínea , Bovinos/metabolismo , Estudios Cruzados , Dieta , Femenino , Manipulación de Alimentos/métodos , Absorción Intestinal , Lactosa/análisis , Hígado/irrigación sanguínea , Hígado/metabolismo , Leche/química , Proteínas de la Leche/análisis , Sistema Porta , Distribución Aleatoria , Circulación Esplácnica
7.
J Dairy Sci ; 84(10): 2231-9, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11699455

RESUMEN

Effects of feeding varying amounts of total gossypol from whole cottonseed and cottonseed meal were evaluated in 30 lactating Holstein cows. After a 14-d pretreatment period, cows were assigned for 42 d to one of five treatments: control (diet A); 1040 mg/kg of total gossypol, and 989 mg/kg of free gossypol from whole cottonseed (diet B); 900 mg/kg of total gossypol and 64 mg/kg of free gossypol from cottonseed meal (diet C); 960 mg/kg of total gossypol and 531 mg/kg of free gossypol with equal amounts of total gossypol from whole cottonseed and cottonseed meal (diet D); or 1922 mg/kg of total gossypol and 1050 mg/kg of free gossypol with equal amounts of total gossypol from whole cottonseed and cottonseed meal (diet E). Concentrations of plasma gossypol and its isomers were directly proportional to free gossypol intake. Plasma gossypol concentrations plateaued after 35 d on treatment, and they were highest in cows receiving diet E. At 42 d on treatment, erythrocyte fragility was higher in the cows receiving the diet E, but it did not differ among other treatments. Dry matter intakes were similar for all groups. Cows receiving diet E produced more milk and 3.5% fat-corrected milk, but milk protein content decreased. Feeding diets containing 1900 mg/kg of total gossypol and 1050 mg/kg of free gossypol for 42 d resulted in increased plasma gossypol concentrations and erythrocyte fragility, but no detrimental impact on lactation performance were observed.


Asunto(s)
Bovinos/fisiología , Aceite de Semillas de Algodón/química , Gosipol/administración & dosificación , Lactancia/efectos de los fármacos , Leche/metabolismo , Animales , Bovinos/metabolismo , Grasas/análisis , Femenino , Gosipol/sangre , Lactancia/metabolismo , Leche/química , Proteínas de la Leche/análisis , Fragilidad Osmótica
8.
J Dairy Sci ; 84(1): 213-24, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11210036

RESUMEN

This study compared the effects of two levels of crude protein (CP) fed during late gestation on the performance, blood metabolites, and ovarian activity of Holstein cows. One-hundred and six cows (42 primigravid and 64 multiparous) 32 d before calving were divided into two groups and fed diets containing moderate (12.7% CP, 36% rumen undegradable protein, (RUP) or high (14.7% CP, 40% RUP) protein. Higher prepartum CP diet increased milk production during the first 120 d in milk (DIM), but most of that effect was detected for the primigravid cows. Primigravid cows fed the prepartum diet higher in protein produced 2.0 kg/d more milk and 3.1 kg/d more 3.5% fat-corrected milk (FCM) during early lactation. Yields of milk fat and protein in early lactation were also increased by the high prepartum CP diet fed to primigravid cows. During the complete lactation, the response to prepartum dietary protein differed between primigravid and multiparous cows. Yields of milk, 3.5% FCM, and milk fat and protein were not affected by the prepartum diet for primigravid cows, but decreased for multiparous cows fed the high protein diet. However, primigravid cows fed the high prepartum protein diet had a higher 305-d mature equivalent milk yield. Colostrum composition, blood metabolites, ovarian activity, and disease incidence were not influenced by prepartum protein. Data from this study suggest that the current prepartum protein recommendation seems to be adequate for multiparous cows, but late-gestation primigravid cows might benefit from diets with a CP content above 12.7%.


Asunto(s)
Bovinos/fisiología , Proteínas en la Dieta/farmacología , Lactancia/fisiología , Leche/química , Reproducción , Animales , Femenino , Número de Embarazos/fisiología , Lactancia/efectos de los fármacos , Lípidos/análisis , Proteínas de la Leche/análisis , Paridad/fisiología , Embarazo , Reproducción/fisiología , Ensilaje/análisis
9.
J Dairy Sci ; 83(8): 1813-28, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10984158

RESUMEN

We assessed the change in milk production in 35 dairy herds located in eight states when a blended animal-marine protein product was included in diets at 2 (22 herds) to 4% (13 herds) of dry matter. Average 305-d production across herds was 8844.1 kg (SEM = 153.7 kg) of milk, with a range of 6876.9 to 11,293.2 kg. The mean days in milk for all herds at initiation of the trial was 118.8 d (SEM = 3.7, herd mean range of 68.8 to 160.0 d), and the average daily milk production was 32.6 kg (SEM = 0.6 kg, range 24.2 to 39.6 kg). The animal-marine protein blend was included in herd rations for 30 d, beginning immediately after a DHI herd test month and ending immediately after the next DHI sample test. Cow milk records were collected for 1 to 2 mo before the protein blend was included and for 2 to 3 mo after the protein was removed. Sample days were assigned a dummy variable to indicate months off or on the animal-marine protein blend. A total of 33,190 milk records from 7135 cows were analyzed. The numbers within herd ranged from 35 to 2012 cows. Of the 35 herds, 19 were classed as having increased milk yield, 12 herds as having no change, and 4 herds as having decreased milk yield when the animal-marine protein blend was included in the diet. The population mean for change in milk yield with the inclusion of the animal-marine protein blend was 1.24 kg/d of milk (SEM = 0.05 kg). There was no significant effect of parity on mean response. Milk protein content was not influenced by animal-marine protein blend inclusion. Fat content was lower for the month on which the animal-marine protein blend was fed (3.51%) compared with the month prior (3.63%) and the month after (3.70%), respectively (SEM = 0.032). Stage of lactation influenced the method for calculating the production response and the actual response to the animal-marine protein blend.


Asunto(s)
Bovinos/fisiología , Proteínas en la Dieta/farmacología , Lactancia/fisiología , Leche/efectos de los fármacos , Leche/metabolismo , Alimentación Animal/análisis , Animales , Femenino , Leche/química
10.
J Dairy Sci ; 83(7): 1530-42, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10908061

RESUMEN

Milk production was simulated in a 50-cow herd averaging 8182 kg of 305-d milk with a standard deviation of 1364 kg. Herd demographics were 35% first lactation, 20% second lactation, and 45% third or greater lactation cows. A lactation model was developed with the Wood's equation (Milk/d = A*DIM*e(-c*dim)) to which random variation was added to be consistent with a coefficient of variation of 10% for daily milk production. Five sequential sampling periods, 30 d apart, were randomly selected for the experiment. For each of these sampling periods data were simulated for cow, lactation number, milk, and days in milk (DIM). To the third sampling period, a known input was pulsed into each cow record to simulate a change in milk production. Inputs and number of herds simulated were -1.140 kg and 15 herds, 0.909 kg and 30 herds, -0.455 kg and 20 herds, 0 kg and 65 herds, 0.455 kg and 21 herds, -0.909 kg and 47 herds, 1.140 kg and 20 herds, and 2.270 kg and 15 herds. Regression by cow was used to estimate milk production change for the known inputs: Milk(ijk) = Intercept + beta(i)*DIM(ij) + TRT(ik) + epsilon(ijk). Parameter estimates for each cow were submitted to analysis of variance with herd as a class variable. The least square mean of TRT (dummy variable for known input of milk volume change) for herd was tested for difference from zero based on a "t" statistic. Herd responses were classed as negative, not different from zero, and greater than zero based on P < 0.10. Herd responses were categorized based on the known input to assess the ability of the method to detect a change in production. The mean estimate of TRT from the regression analysis was used to assess the ability of the method to estimate the magnitude of the known input. The regression method was able to detect changes in production greater than 0.455 kg, but is more useful when changes of 0.9 kg or greater are shown. Adjustment for days postcalving on first test day is necessary to correct for the bias in linear regression to estimate response across the curvilinear milk production function.


Asunto(s)
Bovinos/fisiología , Lactancia/fisiología , Análisis de Regresión , Animales , Industria Lechera/métodos , Femenino , Leche , Sensibilidad y Especificidad , Programas Informáticos
11.
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
12.
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
13.
J Dairy Sci ; 83(5): 1004-15, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10821576

RESUMEN

This study compared the effects of exogenous bovine somatotropin (bST) on the metabolism and ovarian activity of cows fed diets differing in ruminally degradable starch. Twenty-four multiparous and eight primiparous Holstein cows in early lactation were divided into four groups and fed diets containing 39% grain as steam-flaked sorghum or steam-rolled corn with or without bST for 90 d in a 2 x 2 factorial design. Flaked sorghum improved energy status of cows during early lactation, tending to increase plasma glucose and insulin. Administration of bST decreased plasma urea nitrogen and increased nonesterified fatty acids (NEFA). Plasma levels of beta-hydroxybutyrate (BHBA) and hepatic concentrations of triglycerides were not altered by treatments. Temporal changes in plasma glucose, urea nitrogen, NEFA, and BHBA were detected in a quadratic manner and insulin increased linearly with time, but treatments did not affect postpartum changes in these metabolites. There were greater decreases in body weight and net energy balance in cows on bST during the first 7 wk of treatment. Cows receiving bST took longer to reach the nadir of negative energy balance, and bST tended to delay the period to reach a positive energy balance. Follicular populations and incidence of cystic ovaries were not affected by treatments, but cows receiving bST had fewer double ovulations. Flaked sorghum increased plasma progesterone during the early luteal phase of the first two postpartum estrous cycles. Feeding more ruminally degradable starch improved the energy status and luteal activity of cows in early lactation.


Asunto(s)
Bovinos/fisiología , Grano Comestible , Manipulación de Alimentos , Hormona del Crecimiento/farmacología , Lactancia/fisiología , Metabolismo , Ovario/fisiología , Ácido 3-Hidroxibutírico/sangre , Animales , Glucemia/metabolismo , Nitrógeno de la Urea Sanguínea , Cuerpo Lúteo/diagnóstico por imagen , Cuerpo Lúteo/fisiología , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Metabolismo Energético , Ácidos Grasos no Esterificados/sangre , Femenino , Insulina/sangre , Ovario/diagnóstico por imagen , Rumen/metabolismo , Almidón/administración & dosificación , Almidón/metabolismo , Ultrasonografía
15.
J Dairy Sci ; 83(3): 430-4, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10750098

RESUMEN

The objective of this study was to evaluate the response of Holstein cows to bovine somatotropin (bST) during advanced lactation and its relationship to energy intake. Twenty-four lactating Holstein cows averaging 21 kg of milk/d, and 292 d in milk were assigned to one of three treatment groups in a randomized block design. Blocks were based on the 14 d of pretreatment milk production, and treatment groups were balanced for days in milk. Treatment 1 was a low-energy diet (1.49 Mcal/kg of dry matter) without bST injection; treatment 2 was the low-energy diet plus injection of 500 mg of bST every 14 d; and treatment 3 was a high-energy diet (1.71 Mcal/kg of dry matter) with bST injections as in treatment 2. Treatment was divided into two periods (1 to 49 and 50 to 98 d) to determine if response to bST and energy changed with time on treatment. Results showed that bST significantly (P < 0.05) increased milk, fat-corrected milk, and fat and protein yields; and feed efficiency (fat-corrected milk per dry matter intake) for both periods. Milk yield responses to bST were greater for cows fed the low-than the high-energy diet in both periods. These data show that bST injections for cows in advanced lactation increased performance, but excessive energy diminished the bST response.


Asunto(s)
Bovinos/fisiología , Dieta , Ingestión de Energía , Hormona del Crecimiento/farmacología , Lactancia/efectos de los fármacos , Leche/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Recuento de Células , Femenino , Lactosa/análisis , Lípidos/análisis , Leche/citología , Proteínas de la Leche/análisis
17.
Med Ref Serv Q ; 19(3): 39-48, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11299608

RESUMEN

Although a portion of the HIV/AIDS population has long been active in seeking out information in support of self-care, little work has been done to examine closely the information needs and information-seeking behaviors of this community relative to the provision of medical reference. This exploratory study provides insight into the types of information HIV positive individuals seek and the resources they consult in gathering information to bolster health and well-being. Having a better understanding of the information needs and information-seeking behaviors of individuals with HIV/AIDS will facilitate information intervention for this community.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/epidemiología , Infecciones por VIH/epidemiología , Servicios de Información/estadística & datos numéricos , Educación del Paciente como Asunto/estadística & datos numéricos , Humanos , Evaluación de Necesidades , Estados Unidos
18.
Med Ref Serv Q ; 19(1): 31-45, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11299655

RESUMEN

The role nurses occupy in the care of the HIV/AIDS affected has evolved over time. This evolution is exhibited in the body of nursing knowledge and is recorded in the published literature. The purpose of this study was to describe landmarks in the evolution of nursing's involvement in the provision of care to HIV/AIDS patients and to examine the body of nursing knowledge relative to HIV/AIDS, employing bibliometric analytic techniques. It was expected that the literature would grow in both breadth and depth concurrent with nursing's increased role in caring for those infected, or at risk for infection, with HIV.


Asunto(s)
Infecciones por VIH/enfermería , Publicaciones Periódicas como Asunto , Bibliometría , Educación en Enfermería , Humanos , Libros de Texto como Asunto
19.
Med Ref Serv Q ; 19(4): 29-37, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11299675

RESUMEN

Diet and nutrition are directly involved in patient care protocols that reflect a shift in the treatment of HIV/AIDS as a chronic disease, with an emphasis on quality of life and expanded life trajectory. Research concerning HIV/AIDS and nutrition is multidisciplinary, yielding study results that appear in a wide variety of scholarly journals. The purpose of this research was to employ bibliometric techniques to evaluate the body of literature specific to HIV/AIDS and nutrition as well as to determine content overlap among major bibliographic citation databases.


Asunto(s)
Bibliometría , Bases de Datos Bibliográficas , Infecciones por VIH/dietoterapia , Fenómenos Fisiológicos de la Nutrición , Dieta , Infecciones por VIH/fisiopatología , Humanos , Estado Nutricional
20.
J Dairy Sci ; 82(11): 2352-7, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10575601

RESUMEN

Thirty-two Holstein cows (8 per treatment) averaging 195 d in milk were assigned to 70 d of treatment on the basis of production during a 14-d pretreatment period, which was used for covariate analysis. The experiment was a randomized block design with a 2 x 2 factorial arrangement of treatments. Factors were normal shade or shade plus evaporative cooling with pressurized spray, plus with or without the administration of bovine somatotropin (bST). Cows receiving bST were injected with 500 mg of bST every 14 d. All cows were fed the same total mixed rations twice daily at approximately 10% in excess of appetite, and water was offered free choice. There were no interactions between bST and the cooling system for any of the variables measured. Milk yield was increased by bST and tended to be greater for cooled cows. Fat percentages were increased by bST, and yields of fat, protein, and 3.5% fat-corrected milk, and the efficiency of conversion of dry matter to milk, whereas evaporative cooling increased body weights and protein yields, but decreased SNF and milk protein percentages. Rectal temperatures and respiration rates also were lower for cooled cows. And, bST increased nonesterified fatty acids in blood serum, suggesting that a part of the energy for increased milk production came from mobilization of body fat. Administration of bST effectively improved performance of cows under hot summer conditions whether evaporatively cooled or not.


Asunto(s)
Bovinos/fisiología , Hormona del Crecimiento/farmacología , Calor , Lactancia/fisiología , Estaciones del Año , Animales , Temperatura Corporal , Ambiente Controlado , Ácidos Grasos no Esterificados/sangre , Femenino , Humedad
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