Forage legumes for energy-efficient animal production : proceedings of a trilateral workshop held in Palmerston North, New Zealand, April 30-May 4, 1984 /

Item 26-A-1

Manual of cattle feeding. A treatise on the laws of animal nutrition and the chemistry of feeding stuffs in their application to the feeding of farm animals.

Mode of access: Internet.

Animal production potential of some new Leucaena accessions in the Markham valley, Papua New Guinea

Signal grass pastures were oversown with four Leucaena spp. planted in hedgerows and evaluated for their agronomic productivity and ability to support steer liveweight gains. Each Leucaena sp. (L. leucocephala, L. pallida, L colli. nst. i., L. trichandra) was planted as seedlings into two I ha paddocks in rows 5 m apart, with I m spacing between trees. Cattle were rotationally grazed on the 2 replicates of each species, as well as on two I ha paddocks of a signal grass on y (Brachiaria decumbens) control, over a 243-day period at a stocking rate of 3 steers/ha. Mean presentation yield and herbage allowance of the Leucaena accessions over the grazing period were highest for L pallida (1100 kg/ha and 0.8 kg DM/kg LW, respectively), followed by L. leucocephala (700 kg/ha and 0.5 kg DM/kg LW), L. collinsii (700 kg/ha and 0.4 kg DM/kg LW) and L. trichandra (300 kg/ha and 0.2 kg DM/kg LW). Despite only moderate presentation yields and herbage allowances, steers grazing L. leucocephala and L. collinsii accessions produced the highest mean liveweight gains (LWG) of 0. and 0.56 kg/hd/d, respectively. While L. pallida produced the highest DM yields, it supported the lowest LWG of 0.36 kg/hd/d. The mean LWGs of steers grazing L. trichandra and the control (grass only) treatments were similar at 0.48 kg/ hd/d. The possible reasons for the differences in steer performance on the different Leucaena accessions are discussed.

Studio del campo di velocità per fluidi in moto laminare all'interno di condotti

Lo scopo di questa tesi è quello di ottenere una rappresentazione grafica del profilo di velocità di un fluido all’interno di un condotto. In particolare si studieranno le equazioni di bilancio facendo alcune ipotesi semplificative riguardo il moto del fluido. Si considererà un moto laminare in condizione di completo sviluppo dinamico e convezione forzata. Grazie a queste ipotesi si riuscirà ad ottenere un’equazione semplificata di Navier-Stokes, che permetterà di calcolare l’andamento della velocità all’interno di condotti con qualsiasi forma della sezione. In questo caso si confronterà il profilo di velocità di un condotto a sezione circolare con uno a sezione circolare forata come in uno scambiatore di calore a tubi concentrici. Per risolvere l’equazione di Navier-Stokes e stampare l’andamento delle velocità all’interno della sezione del condotto si è utilizzato il software “Mathematica”, che è stato appreso durante l’attività di tirocinio curriculare. Questo software offre un supporto notevole allo studio matematico di qualsiasi problema. Permette inoltre di avere un riscontro grafico dei risultati ottenuti, direttamente nell’interfaccia utilizzata per la stesura del codice. Per rappresentare il profilo di velocità sarà inoltre utilizzato il metodo degli elementi finiti all’interno di Mathematica, che permetterà di ottenere una soluzione più uniforme e vicina alla realtà. Il metodo degli elementi finiti (FEM) permette di semplificare lo studio del moto di un fluido, in quanto ci dà la possibilità di avere un sistema di equazioni algebriche che ne descrivono il moto, invece di equazioni differenziali e le sue relative condizioni al contorno. Sarà quindi brevemente descritto questo metodo che è stato di grande aiuto tramite l’implementazione della “mesh” su Mathematica.

Avaliação in vivo do potencial regenerativo na Degeneração Walleriana de nervos periféricos - com a utilização de laser de baixa potência e composto polivitamínico 3-NERVE

Dissertação (Mestrado em Tecnologia Nuclear)

Pharmacokinetics of UC781-loaded intravaginal ring segments in rabbits: a comparison of polymer matrices

UC781 is a potent and poorly water-soluble nonnucleoside reverse transcriptase inhibitor being investi- gated as a potential microbicide for preventing sexual transmission of HIV-1. This study was designed to evaluate the in vivo release and pharmacokinetics of UC781 delivered from matrix-type intravaginal ring segments in rabbits. Three polymer matrices (polyurethane, ethylene vinyl acetate copolymer, and silicone elastomer) and two drug loadings (5 and 15 mg/segment) were evaluated in at least one of two independent studies for up to 28 days in vivo. Inter-study comparison of in vivo release, vaginal tissue, and plasma concentrations for similar formulations demonstrated good reproducibility of the animal model. Mean estimates for a 28-day in vivo release ranged from 0.35 to 3.17 mg UC781 per segment. Mean proximal vaginal tissue levels (adjacent to the IVR segment) were 8– 410 ng/g and did not change significantly with time for most formulations. Distal vaginal tissue levels of UC781 were 6- to 49-fold lower than proximal tissue levels. Mean UC781 plasma levels were low for all formulations, at 0.09–0.58 ng/mL. All formulations resulted in similar UC781 concentrations in vaginal tissue and plasma, except the low loading polyurethane group which provided significantly lower levels. Loading dependent release and pharmacokinetics were only clearly observed for the polyurethane matrix. Based on these results, intravaginal ring segments loaded with UC781 led to vaginal tissue concen- trations ranging from below to approximately two orders of magnitude higher than UC781’s EC50 under in vitro conditions (2.8 ng/mL), with little influence by polymer matrix or UC781 loading. Moreover, these findings support the use of rabbit vaginal pharmacokinetic studies in preclinical testing of microbicide intravaginal rings.

Ex vivo experimental model for percutaneous vertebroplasty: microCT utility

The aim of this study was to develop an ex vivo experimental animal model for percutaneous vertebroplasty, for further application in vivo to test novel bone injectable cements.

Regulation of Radial Glial Motility by Visual Experience

Radial glia in the developing optic tectum express the key guidance molecules responsible for topographic targeting of retinal axons. However, the extent to which the radial glia are themselves influenced by retinal inputs and visual experience remains unknown. Using multiphoton live imaging of radial glia in the optic tectum of intact Xenopus laevis tadpoles in conjunction with manipulations of neural activity and sensory stimuli, radial glia were observed to exhibit spontaneous calcium transients that were modulated by visual stimulation. Structurally, radial glia extended and retracted many filopodial processes within the tectal neuropil over minutes. These processes interacted with retinotectal synapses and their motility was modulated by nitric oxide (NO) signaling downstream of neuronal NMDA receptor (NMDAR) activation and visual stimulation. These findings provide the first in vivo demonstration that radial glia actively respond both structurally and functionally to neural activity, via NMDAR-dependent NO release during the period of retinal axon ingrowth.

The efficacy of a single chain recombinant equine luteinizing hormone (reLH) in mares: Induction of ovulation, hormone profiles, and inter-ovulatory intervals

The objectives of this study were to determine the efficacy of recombinant equine luteinizing hormone (reLH) in shortening the time to ovulation in cycling mares and to determine the effects of treatment on endogenous hormones and inter-ovulatory intervals. In study 1, mares of light horse breeds (3-20 years) were treated with either a vehicle, various doses of reLH, or human chorionic gonadotropin (hCG). Cycling mares were examined by palpation and ultrasound per rectum daily or every 12 h from the time of treatment to ovulation. In studies 2 and 3, jugular blood samples were collected daily or every 12 h from the time of treatment to ovulation for analysis of LH, follicle stimulating hormone (FSH), estradiol-17 beta (E-2), and progesterone (P-4) by radioimmunoassays (RIA). Increasing doses of reLH (0.3, 0.6, 0.75, and 0.9 mg) showed increasing effectiveness at inducing ovulation within 48 h of treatment. Treatments with the 0.75 and 0.9 mg doses of reLH resulted in 90% and 80% ovulation rates, which were similar to hCG treatment (85.7%). Except for the early rise in LH after treatment with 0.5, 0.65, and 1.0 mg of reLH, hormone profiles appeared to be similar between control and treated cycles. Inter-ovulatory intervals were similar between control and treatment cycles. In conclusion, reLH is a reliable and effective ovulatory agent that does not significantly alter endogenous hormone profiles or affect inter-ovulatory intervals.(c) 2007 Elsevier B.V. All rights reserved.

Clastogenicidade e /ou aneugenicidade do hormônio androgênico nandrolona (Deca-Durabolin®) em camundongos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Highly efficient in vivo agonist-induced internalization of sst2 receptors in somatostatin target tissues

The successful peptide receptor imaging of tumors, as exemplified for somatostatin receptors, is based on the overexpression of peptide receptors in selected tumors and the high-affinity binding to these tumors of agonist radioligands that are subsequently internalized into the tumor cells in which they accumulate. Although in vitro studies have shown ample evidence that the ligand-receptor complex is internalized, in vivo evidence of agonist-induced internalization of peptide receptors, such as somatostatin receptors, is missing. METHODS: Rats subcutaneously transplanted with the somatostatin receptor subtype 2 (sst(2))-expressing AR42J tumor cells were treated with intravenous injections of various doses of the sst(2) agonist [Tyr(3), Thr(8)]-octreotide (TATE) or of the sst(2) antagonist 1,4,7,10-tetraazacyclododecane-N,N',N'',N''',-tetraacetic acid (DOTA)-Bass and were sacrificed at various times ranging from 2.5 min to 24 h after injection. The tumors and pancreas were then removed from each animal. All tissue samples were processed for sst(2) immunohistochemistry using sst(2)-specific antibodies. RESULTS: Compared with the sst(2) receptors in untreated animals, which localized at the plasma membrane in pancreatic and AR42J tumor cells, the sst(2) receptors in treated animals are detected intracellularly after an intravenous injection of the agonist TATE. Internalization is fast, as the receptors are already internalizing 2.5 min after TATE injection. The process is extremely efficient, as most of the cell surface receptors internalize into the cell and are found in endosomelike structures after TATE injection. The internalization is most likely reversible, because 24 h after injection the receptors are again found at the cell surface. The process is also agonist-dependent, because internalization is seen with high-affinity sst(2) agonists but not with high-affinity sst(2) antagonists. The same internalization properties are seen in pancreatic and AR42J tumor cells. They can further be confirmed in vitro in human embryonic kidney-sst(2) cells, with an immunofluorescence microscopy-based sst(2) internalization assay. CONCLUSION: These animal data strongly indicate that the process of in vivo sst(2) internalization after agonist stimulation is fast, extremely efficient, and fully functional under in vivo conditions in neoplastic and physiologic sst(2) target tissues. This molecular process is, therefore, likely to be responsible for the high and long-lasting uptake of sst(2) radioligands seen in vivo in sst(2)-expressing tumors.

Efeito do teor proteico da dieta na digestibilidade da bolota em porcos alentejanos

O objectivo do presente ensaio é avaliar o efeito do teor proteico da dieta na digestibilidade da bolota em porcos Alentejanos. Para tal, nove animais foram seccionados e colocados em caixas metabólicas onde as dietas foram distribuídas aleatoriamente, segundo o Modelo de Quadrado Latino 3 x 3. O ensaio in vivo foi assim dividido em três períodos, durante os quais se recolheram amostras de alimento, refugos fezes e urina para posterior análise em laboratório. Foi determinada a composição química do alimento e calculada a digestibilidade e balanço de azoto dos três tratamentos. Também foi determinado o conteúdo em compostos fenólicos e taninos da bolota pelo método do Folin­ Ciocalteu, taninos condensados pelo método do Butanol-HCl e a capacidade complexante dos taninos pelo método da Difusão Radial. Devido à reduzida capacidade de os taninos complexarem as proteínas e à baixa ingestão da luzerna não foi possível verificar diferenças na proteína ingerida entre os tratamentos testados. ABSTRACT; The aim of present experiment is to evaluate the effect of protein content in diet digestibility of oak acorn in Alentejano pigs. For that, nine animals were selected and housed in metabolic cages where diets were given randomly, in a Latin Square model3 x 3. The in vivo experiment was divided in three periods, during which were collected feed, refusals, feces and urine samples for subsequent laboratory analyses. Chemical feed composition was determinate and calculated the digestibility and nitrogen balance in three treatments. It was also determinate the amount of phenolic compounds and tannins on oak acorn by Folin-Ciocalteu assay, condensed tannins by Butanol-HCl assay and the availability to form complex with protein by Radial Diffusion assay. It was observed a reduced availability of tannins to bind proteins and a low Lucerne intake, so it wasn't possible to verify differences on protein intake, between tested treatments.

Efeito acaricida in vivo do extrato aquoso de Daphnopsis racemosa e de Natur N sobre larvas e ninfas de Rhipicephalus (Boophilus) microplus.

As limitações atuais do controle químico parasitário e a riqueza e grande diversidade da flora brasileira têm estimulado a pesquisa com extratos de plantas na busca por novas formas de controle.

El potencial de aprendizaje : un modelo y un sistema aplicado de evaluación.

Recoger los primeros intentos de evaluación dinámica y las demandas que la escuela y sociedad tienen planteadas en el campo de la evaluación psicológica. Realizar un estudio sobre los principios teóricos que sustentan al modelo de evaluación del potencial de aprendizaje de Feuerstein. A partir de los principios de la teoría del procesamiento de la información en el que se incluiría el modelo de Feuerstein, se trata, de diseñar un modelo de evaluación dinámica (test-entrenamiento-test) y señalar los perfiles que tendría la evaluación del potencial de aprendizaje (Vigotsky, 1962). A través de una concepción dinámica de la evaluación de la inteligencia y tomando como base las teorías de Feuerstein (teoría de la modificabilidad estructural cognitiva), se llega a proponer el diseño de evaluación del potencial de aprendizaje (LPAD), considerando el aspecto tridimensional (novedad, lenguaje, operación) de los tests que componen la batería del LPAD. De la evaluación del potencial de aprendizaje se definen unos perfiles que vienen a representar una regla conceptual que permite al examinador, organizar, describir, analizar e interpretar de forma sistemática los cambios que se producen en el examinando a lo largo de la evaluación. Estos perfiles también contemplarían las dimensiones de la interacción examinador-examinando, mediante la experiencia del aprendizaje mediado. Vid bibliografía. Test de organización de punto (adaptación de Feuerstein del original de Andre Rey, 1934). Matrices progresivas de Raven. Figura compleja de rey. Test de aprendizaje de posición (adaptación de Feuerstein del original 'enumeración de puntos' de André Rey, 1958). Diseño de patrones (adaptación de Feuerstein del original de Grace Arthur, 1936). Bandejas (adaptación de Feuerstein del original 'plateaux de André Rey, 1950). Progresiones numéricas. Test de memoria asociativa. Test de memoria de palabras. Análisis comparativo de los modelos de evaluación de la inteligencia: estáticos frente a dinámicos. Se analizan los componentes de la teoria de la modificabilidad estructural cognitiva de Feuerstein y la batería de evaluación del potencial de aprendizaje. El LPAD es un modelo idóneo para la evaluación de las capacidades básicas de la inteligencia, que permite el estadio de la competencia del sujeto y posibilita la transferencia en los aprendizajes escolares. Apuntan a la necesidad de establecer acuerdos mínimos sobre la evaluación del potencial de aprendizaje, y como aumentar dicho potencial a través de modelos adecuados de enriquecimiento cognitivo.