The purpose of this paper is to show the conditions that must be verified before use any of the classic linear analysis methods for oscillator design. If the required conditions are not verified, the classic methods can provide wrong solutions, and even when the conditions are verified each classic method can provide a different solution. It is necessary to use the Normalized Determinant Functi...

The impact was studied of buffer pH (5.8, 6.2, and 6.8) on in vitro digestion kinetics of NDF from alfalfa hay, bromegrass hay, corn silage, and alfalfa and bromegrass hays with raw corn starch added to approximate a ration containing 30% NDF. Ash-free NDF was determined at 0, 6, 12, 18, 24, 30, 36, 48, 72, and 96 h of fermentation. Kinetic parameters were estimated by nonlinear regression usin...

Five in situ trials with whole-plant corn silage (WPCS) were conducted in two ruminallycannulated Holstein cows to determine 24-h ruminal disappearance of dry matter (DM), starch, and neutral detergent ®ber (NDF). In Trial 1, the effect of maturity of WPCS on ruminal nutrient disappearance was evaluated. Treatments were early dent (ED), 1/4 milk-line (1/4 ML), 2/3 milkline (2/3 ML), and black-l...

In livestock nutrition, summative models (SM) are displacing empirical models as a preferred method to predict energy content of forages. The objective of this study was to determine the effect of using near infrared reflectance spectroscopy (NIRS) to determine nutrient subcomponents required of SM on overall ability to predict energy content of corn and legume-grass silages. Corn (n = 90) and ...

Twelve Nebraska Sandhills upland range paddocks were utilized in a two year study to determine effects of stocking rate on grazed forage nutrient composition in early summer. Stocking rates consisted of control, light, and heavy stocked at 0, 0.57, and 0.85 animal unit months per hectare respectively. Three esophageally fistulated cows per paddock collected diet samples on May 14 (d 0), May 21 ...

Neu differentiation factor (NDF/heregulin) is a 44-kDa glycoprotein that interacts with the Neu/ErbB-2 receptor tyrosine kinase to increase its phosphorylation on tyrosine residues. In vitro NDF promotes differentiation of certain mammary tumor cell lines to milk-producing cells. As a first step toward understanding the physiological role of NDF, we performed in situ hybridization analyses to d...

nine multiparous lactating cows averaging 171 days in milk were divided according to days in milk and milk production into three 3×3 latin squares with three 3-week periods to investigate the effect of rumen degradable protein on milk urea nitrogen. diets were formulated to provide 3 concentrations of dietary rumen degradable protein (9.8, 10.8, and 11.8% of dry matter), while rumen undegradabl...

An automatic in vitro gas production technique was evaluated for predicting in vivo fiber (NDF) digestibility and effective first-order digestion rate of potentially digestible NDF (pdNDF) of 15 grass silages. Observed in vivo NDF digestibility of the silages harvested at different stages of maturity during 3 yr was determined by the total fecal collection in sheep fed at the maintenance level ...

introduction: demands of agricultural products, particularly in developing countries, are increasing rapidly. consequently, land and water resources are unable to sustain such demands. for decades, rangelands in africa, west and central asia suffered from overgrazing and many areas are severely degraded. range vegetation used to be the main feed resource for livestock particularly in the arid a...