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Full-Text Articles in Medicine and Health Sciences
Development Of A Mechanistic Model To Represent The Dynamics Of Particle Flow Out Of The Rumen And To Predict Rate Of Passage Of Forage Particles In Dairy Cattle., S Seo, Cristina Lanzas, L O. Tedeschi, A Pell, D G. Fox
Development Of A Mechanistic Model To Represent The Dynamics Of Particle Flow Out Of The Rumen And To Predict Rate Of Passage Of Forage Particles In Dairy Cattle., S Seo, Cristina Lanzas, L O. Tedeschi, A Pell, D G. Fox
Cristina Lanzas
A mechanistic and dynamic model was developed to represent physiological aspects of particle dynamics in the reticulo-rumen (RR) and to predict rate of passage out of the RR (Kp) of forage particles quantitatively. The model consists of 2 conceptual pools with 3 spatial compartments of particles; the compartment the particle enters is based on functional specific gravity (FSG). The model assumes 2 major pressure gradient-driven flows of particles out of the RR through the reticulo-omasal orifice between 2 consecutive primary reticular contractions. One is associated with the second phase of primary reticular contraction and involves propulsion of particles in the …
Improved Feed Protein Fractionation Schemes For Formulating Rations With The Cornell Net Carbohydrate And Protein System, Cristina Lanzas, G A. Broderick, D G. Fox
Improved Feed Protein Fractionation Schemes For Formulating Rations With The Cornell Net Carbohydrate And Protein System, Cristina Lanzas, G A. Broderick, D G. Fox
Cristina Lanzas
Adequate predictions of rumen-degradable protein (RDP) and rumen-undegradable protein (RUP) supplies are necessary to optimize performance while minimizing losses of excess nitrogen (N). The objectives of this study were to evaluate the original Cornell Net Carbohydrate Protein System (CNCPS) protein fractionation scheme and to develop and evaluate alternatives designed to improve its adequacy in predicting RDP and RUP. The CNCPS version 5 fractionates CP into 5 fractions based on solubility in protein precipitant agents, buffers, and detergent solutions: A represents the soluble nonprotein N, B1 is the soluble true protein, B2 represents protein with intermediate rates of degradation, B3 is …
Development Of A Mechanistic Model To Represent The Dynamics Of Liquid Flow Out Of The Rumen And To Predict The Rate Of Passage Of Liquid In Dairy Cattle, S Seo, Cristina Lanzas, L O. Tedeschi, D G. Fox
Development Of A Mechanistic Model To Represent The Dynamics Of Liquid Flow Out Of The Rumen And To Predict The Rate Of Passage Of Liquid In Dairy Cattle, S Seo, Cristina Lanzas, L O. Tedeschi, D G. Fox
Cristina Lanzas
A mechanistic and dynamic model was developed to represent the physiological aspects of liquid dynamics in the rumen and to quantitatively predict liquid flow out of the reticulorumen (RR). The model is composed of 2 inflows (water consumption and salivary secretion), one outflow (liquid flow through the reticulo-omasal orifice (ROO), and one in-and-out flow (liquid flux through the rumen wall). We assumed that liquid flow through the ROO was coordinated with the primary reticular contraction, which is characterized by its frequency, duration, and amplitude during eating, ruminating, and resting. A database was developed to predict each component of the model. …
Evaluation Of Protein Fractionation Systems Used In Formulating Rations For Dairy Cattle, Cristina Lanzas, S Seo, L O. Tedeschi, D G. Fox
Evaluation Of Protein Fractionation Systems Used In Formulating Rations For Dairy Cattle, Cristina Lanzas, S Seo, L O. Tedeschi, D G. Fox
Cristina Lanzas
Production efficiency decreases when diets are not properly balanced for protein. Sensitivity analyses of the protein fractionation schemes used by the National Research Council Nutrient Requirement of Dairy Cattle (NRC) and the Cornell Net Carbohydrate and Protein System (CNCPS) were conducted to assess the influence of the uncertainty in feed inputs and the assumptions underlying the CNCPS scheme on metabolizable protein and amino acid predictions. Monte Carlo techniques were used. Two lactating dairy cow diets with low and high protein content were developed for the analysis. A feed database provided by a commercial laboratory and published sources were used to …
Digestion Kinetics Of Dried Cereal Grains, Cristina Lanzas, A N. Pell, D G. Fox
Digestion Kinetics Of Dried Cereal Grains, Cristina Lanzas, A N. Pell, D G. Fox
Cristina Lanzas
Grain fermentability largely determines the feed value of grains for ruminants. Our objective was to evaluate the variation in kinetics of gas production of cereal grains and the relationship among gas production, chemical composition and feed value. Eighteen barley, 99 corn, 23 sorghum, and 57 wheat samples were fermented in vitro for 48 h. Gas production was measured with a computerized system and an exponential model was fitted to the data. The impact of the variation in composition and kinetics on the feed value of grains in feedlot rations was assessed with the Cornell Net Carbohydrate and Protein System (CNCPS). …
A Revised Cncps Feed Carbohydrate Fractionation Scheme For Formulating Rations For Ruminants, Cristina Lanzas, C J. Sniffen, S Seo, L O. Tedeschi, D G. Fox
A Revised Cncps Feed Carbohydrate Fractionation Scheme For Formulating Rations For Ruminants, Cristina Lanzas, C J. Sniffen, S Seo, L O. Tedeschi, D G. Fox
Cristina Lanzas
Balancing ruminant diets for appropriate levels and types of dietary carbohydrates (CHO) is necessary to maximize production while assuring the health of the animals. Several feed fractions (i.e., volatile fatty acids (VFA), lactate, sugars, starch) are now being measured in some commercial feed laboratories and this information may assist in better formulating diets. A CHO fractionation scheme based on ruminal degradation characteristics needed for nutritional models is described and its impact on predictions with the Cornell Net Carbohydrate and Protein System (CNCPS) is assessed. Dietary CHO are divided into eight fractions: the CA1 is volatile fatty acids (VFA), CA2 is …