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1.
Br Poult Sci ; 65(3): 315-330, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38393938

RESUMEN

1. Effects of cereal type and conditioning temperature (CT) on protein and carbohydrate (CHO) molecular structures, nutrient retention, carcass and blood characteristics, caecal microbial population and growth criteria of broilers fed pellet diet were evaluated for a total period of 35 d.2. In total, 336-day-old Cobb 500 broiler chicks were randomly allotted into a 2 × 2 factorial arrangement with two different cereal types (maize or wheat) processed in two different temperatures (CT; 68°C or 90°C) with seven pen replicates containing 12 birds each.3. Chicks fed the maize-based diets significantly gained higher body weight (BW) and lower feed conversion ratio (FCR) in comparison to the chicks fed wheat-based diets during the whole grow-out period (p < 0.01). Overall, the highest BW and feed intake (FI) were seen in birds fed wheat-based diets conditioned at 68°C, but the lowest FCR was observed in maize-based diet conditioned at 90°C at 7, 14 and 21 d of age (p < 0.01). However, BW was higher and FCR lower in chicks fed maize-based diets conditioned at 90°C in the grower period (28 and 35 d; p < 0.01).4. The α-helix height was higher in wheat-based starter diets in comparison to the maize-based diet (p < 0.01). Ratio of amide I to II area and total CHO peak height were increased when diets were processed at 90°C in both maize and wheat-based starter diet (p < 0.05). Increasing the CT from 68°C to 90°C reduced CHO peak 1 and 2 height by 11.6% and 3.95%, respectively, in maize-based starter diets, while increasing the CT from 68°C to 90°C reduced CHO peak 1 and 2 height by 54.3% and 57.2%, respectively, in wheat-based starter diets. In the grower diets, increasing the CT from 68°C to 90°C increased CHO peak 1 by 23% in maize-based diets, but reduced CHO peak 1 by 24.5% in wheat-based diets.5. Calcium and phosphorous retention were highest in chicks fed wheat-based diets conditioned at 90°C and lowest in chicks fed maize-based diets conditioned at 90°C (p < 0.01). Salmonella, E. coli and coliforms in the caeca reduced significantly (p < 0.05) in chicks fed wheat-based diets conditioned at 90°C on d 11 and increased with the same diet at 35 d of age compared to the chicks fed maize-based diets conditioned at both 68°C and 90°C or wheat-based diets conditioned at 68°C.6. Conditioning the wheat-based diets at 68°C improved production responses without causing any adverse effects on protein and CHO molecular structures, however increasing the conditioning temperature to 90°C impaired performance due to alteration of protein and CHO molecular structures. In contrast, conditioning of the maize-based diets at 90°C had the opposite effect, and improved production performance compared to diets conditioned at 68°C.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Pollos , Dieta , Proteínas en la Dieta , Triticum , Zea mays , Animales , Pollos/crecimiento & desarrollo , Pollos/fisiología , Alimentación Animal/análisis , Dieta/veterinaria , Zea mays/química , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Triticum/química , Proteínas en la Dieta/metabolismo , Proteínas en la Dieta/administración & dosificación , Distribución Aleatoria , Grano Comestible/química , Masculino , Carbohidratos de la Dieta/administración & dosificación , Carbohidratos de la Dieta/metabolismo , Temperatura
2.
Opt Express ; 31(25): 42347-42357, 2023 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-38087610

RESUMEN

We purpose and demonstrate the switchable multi-wavelength Brillouin-Raman fiber laser (MBRFL) through a bi-directional Raman pumping scheme. The laser structure is arranged in a linear cavity by including a physical mirror at one side of the cavity. The switching operation for MBRFL with single- and double-wavelength spacing is implemented by optimizing the Raman power distribution through a variable optical coupler. This effect on feedback power of the physical mirror provides the difference between odd- and even-order Stoke lines' maximum power on different sides of the cavity with 10 GHz and 20 GHz spacing. A 90/10 coupler is found to be the optimal. Up to 460 flat-amplitude lines within only a 0.5-dB flatness range, average -5 dBm Stokes peak power (SPP), 10 GHz frequency spacing, and an average optical signal-to-noise ratio (OSNR) of 26 dB are observed. All the counted laser lines are spread across a 37 nm bandwidth. Simultaneously, 170 Stoke lines with overall -2 dBm SPP, 28 dB OSNR, and 20 GHz frequency spacing are attained on other side of the cavity. These are achieved when the Raman pump power is set only at 900 mW. To date, this is the simplest cavity design with the flattest spectrum and highest output power for both wavelength spacing and excellent OSNR achieved in multi-wavelength fiber lasers that incorporate a single low-power Raman pump unit.

3.
Br Poult Sci ; 60(3): 297-308, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30836768

RESUMEN

1. The current experiment was performed to elucidate the effects of degelatinised bone meal (DBM) in combination with different particle sizes of limestone or oyster shell on broiler performance, bone characteristics and digestive and plasma alkaline phosphatase (ALP) activity. 2. Treatments were applied as a 3 × 3 factorial arrangement with three sources of P (DCP, bone meal and DBM) and three particle sizes (50, 100 and 200 µm) of limestone. Chickens were given either DCP or DBM with oyster shell (523 µm), resulting in a total of 11 treatments with 5 replicates of 8 chicks. 3. Performance criteria were measured weekly. Tibia strength, ash, calcium (Ca) and phosphorus (P) content and plasma P and Ca concentration along with plasma and intestinal alkaline phosphatase (ALP) activity and P digestibility were measured on d 14 and 28. 4. Body weight and FCR were improved in chicks which were fed DBM or oyster shell in comparison to the DCP and limestone respectively (P ≤ 0.05). Performance was influenced (P ≤ 0.05) by particle size; with coarser particles BW and feed intake were increased (P ≤ 0.05). Tibia shear force and P content were reduced (P ≤ 0.001), whereas tibia shear energy, length, ash and Ca content were increased by substitution of DCP with DBM or bone meal (P ≤ 0.001; P ≤ 0.05). A significant difference was observed in the tibia length between the chicks fed oyster shell or limestone with different particles (P ≤ 0.05). Plasma P concentration was reduced in chicks were fed with DBM, bone meal and lower limestone particle size. Intestinal ALP activity was increased (P ≤ 0.001) in chicks which were fed DBM, bone meal, oyster shell or coarse particles of limestone. The P digestibility in chicks fed bone meal was lower than that of those fed DBM or DCP (P ≤ 0.01). Overall, gelatin removal from bone meal improved broiler bone characteristics through the P digestibility and intestinal ALP activity enhancement.


Asunto(s)
Fosfatasa Alcalina/metabolismo , Huesos/química , Calcio de la Dieta/metabolismo , Pollos/fisiología , Minerales/química , Fósforo Dietético/metabolismo , Fosfatasa Alcalina/sangre , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Productos Biológicos/química , Desarrollo Óseo/efectos de los fármacos , Calcio de la Dieta/administración & dosificación , Digestión/efectos de los fármacos , Tracto Gastrointestinal/enzimología , Masculino , Tamaño de la Partícula , Fósforo Dietético/administración & dosificación , Distribución Aleatoria
4.
Mater Sci Eng C Mater Biol Appl ; 59: 740-747, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26652428

RESUMEN

In this study chitosan/halloysite nanotube composite (CS/HNT) coatings were deposited by electrophoretic deposition (EPD) on titanium substrate. Using HNT particles were investigated as new substituents for carbon nanotubes (CNTs) in chitosan matrix coatings. The ability of chitosan as a stabilizing, charging, and blending agent for HNT particles was exploited. Furthermore, the effects of pH, electrophoretic bath, and sonicating duration were studied on the deposition of suspensions containing HNT particles. Microstructure properties of coatings showed uniform distribution of HNT particles in chitosan matrix to form smooth nanocomposite coatings. The zeta potential results revealed that at pH around 3 there is an isoelectric point for HNT and it would have cathodic and anionic states at pH values less and more than 3, respectively. Therefore, CS/HNT composite deposits were produced in the pH range of 2.5 to 3. The apatite inducing ability of chitosan-HNT composite coating assigned that HNT particles were biocompatible because they formed carbonated hydroxyapatite particles on CS/HNT coating in corrected simulated body fluid (C-SBF). Finally, electrochemical corrosion characterizations determined that corrosion resistance in CS/HNT coating has been improved compared to bare titanium substrate.


Asunto(s)
Silicatos de Aluminio/química , Apatitas/química , Quitosano/química , Materiales Biocompatibles Revestidos/química , Nanotubos/química , Titanio/química , Arcilla , Corrosión , Electroforesis
5.
Poult Sci ; 94(7): 1483-92, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25910901

RESUMEN

This experiment was conducted using 192 day-old Ross 308 chicks, divided into 4 groups of 4 replicate consisting 48 birds. Group I was fed a control diet, Group II was fed control diet supplemented with 0.5 ppm T-2 toxin for 5 weeks, Group III was fed control diet supplemented with 8 × 10(8) cfu/mL of Mycoplasma gallisepticum, and group IV was fed control diet supplemented by T-2 toxin and Mycoplasma gallisepticum. Body weight and feed conversation ratio (FCR), relative organ weights, clinical signs, biochemical characteristics, and gross and histopathological lesions were recorded in the experimental groups at the end of the second and fifth weeks of age. Body weight and relative weights of bursa of Fabricius, thymus, and spleen decreased and FCR increased significantly (P ≤ 0.05), but the relative weights of liver and kidney showed no significant decrease (P ≤ 0.05) in the serum total proteins, albumin, and increase in aspartate aminotransferase and alanine transaminase were observed in T-2 toxin and T-2 accompanied with Mycoplasma fed birds when compared to the control group. Liver was enlarged, friable, and yellowish discoloration with distended gall bladder was noticed. Lymphoid organs such as bursa of Fabricius, thymus, and spleen were atrophied in group II and group IV throughout the study. Microscopically, liver showed vacuolar degeneration of hepatocytes, with increased Kupffer cell activity, bile duct epithelial hyperplasia, and infiltration of inflammatory cells. Kidney showed vacuolar degeneration of tubular epithelium along with pyknotic nuclei. Lymphoid organs showed lymphocytolysis and depletion with prominent reticuloepithelial cells. Proventriculus revealed desquamation of villous epithelial cells and lymphoid infiltration in submucosa. Heart showed mild hemorrhage with infiltration of inflammatory cells. Lung showed edema and inflammatory cells in the bronchioles. Trachea showed desquamation and erosions of mucosa. Proliferation of mucosal glands with increased mucous secretion was obvious. Air sacs showed thickening with presence of inflammatory cells and edema.


Asunto(s)
Pollos , Coinfección/patología , Infecciones por Mycoplasma/patología , Enfermedades de las Aves de Corral/patología , Toxina T-2/toxicidad , Animales , Peso Corporal , Coinfección/microbiología , Coinfección/veterinaria , Digestión , Femenino , Terapia de Inmunosupresión , Masculino , Infecciones por Mycoplasma/microbiología , Mycoplasma gallisepticum/fisiología , Tamaño de los Órganos , Enfermedades de las Aves de Corral/microbiología
6.
J Dairy Sci ; 93(9): 4111-20, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20723686

RESUMEN

The primary objective was to determine pre- and postweaning calf physiological responses to increased Cr supply under high ambient temperatures. In a randomized complete block design, 24 neonate Holstein calves (BW=41.5+/-1.9 kg) were grouped based on sex and randomly assigned to 3 treatments within each group. Treatments included either no supplemental Cr (control), 0.02 mg of supplemental Cr/kg of BW0.75, or 0.04 mg of supplemental Cr/kg of BW0.75. The average temperature-humidity index was 77 during the study. Chromium was provided as a commercial product in whole milk for preweaning calves and in a starter concentrate for postweaning calves. Calves were weaned at 1 kg of daily calf starter intake lasting for 6 consecutive days. A glucose tolerance test was conducted on d 25 postweaning. Treatments had no effects on preweaning dry matter intake, feed conversion ratio, average daily gain, and weaning age. Chromium decreased dry matter intake in postweaning calves; however, it did not affect growth and feed conversion ratio. Chromium lowered respiration rate at wk 5 without affecting fecal score and rectal temperature. Preweaning serum cortisol concentrations were altered by a 3-way interaction of Cr dose with calf sex and age. Preweaning serum glucose showed week-dependent increases by Cr. Serum insulin, urea, albumin, total protein, triiodothyronine, and thyroxin concentrations through weaning were not affected. The increasing Cr doses caused quadratic declines in serum thyroxin on d 21 postweaning, whereas blood triiodothyronine declined only with the higher Cr dose. Serum NEFA remained unchanged, but BHBA decreased by Cr in male calves on d 21 postweaning. The glucose tolerance test revealed linear reductions in area under insulin curve between 0 to 90 and 0 to 120 min after glucose infusion, suggesting improvements in peripheral insulin efficiency. Sex-dependent responses to Cr were observed for serum total protein and albumin concentrations at 21 d postweaning. Overall, results indicate that in summer, increased dietary Cr supply can benefit postweaning insulin metabolism, alter preweaning blood cortisol and glucose levels, and reduce respiration rate and may have only minor effects on calf growth.


Asunto(s)
Bovinos/crecimiento & desarrollo , Cromo/farmacología , Suplementos Dietéticos , Factores de Edad , Animales , Glucemia/análisis , Temperatura Corporal/efectos de los fármacos , Temperatura Corporal/fisiología , Bovinos/sangre , Bovinos/fisiología , Cromo/sangre , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Ingestión de Alimentos/fisiología , Ácidos Grasos no Esterificados/sangre , Femenino , Prueba de Tolerancia a la Glucosa/veterinaria , Hidrocortisona/sangre , Insulina/sangre , Masculino , Frecuencia Respiratoria/efectos de los fármacos , Frecuencia Respiratoria/fisiología , Estaciones del Año , Albúmina Sérica/análisis , Factores Sexuales , Destete , Aumento de Peso/efectos de los fármacos , Aumento de Peso/fisiología
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