Effects of Inoculation and Wilting on the Preservation and Utilization of Wheat Forage

Wheat forage was harvested at an early head stage of maturity and ensiled in 12 900-kg experimental silos at three percentages of DM (20.8% for direct-cut forage and 27.9 or 39.3% for wilted forage) either with or without application of a lactic acid bacterial inoculant. The objective was to test the efficacy of the inoculant to alter silage fermentation, preservation, and nutritive value of wheat forage ensiled at different moisture percentages because of wilting. Wilting enhanced DM preservation and decreased fermentation end products. Inoculation made the fermentation more homolactic but did not enhance DM preservation. Silage rations (80% DM as silage) were fed at 1.8% of BW/d to six ruminally and abomasally fistulated steers (350 kg) in an experiment with a Latin-square design and a 3 × 2 factorial arrangement of treatments. Digestive responses to silage diets were not influenced by inoculation. Intake was depressed with direct-cut silage rations. Wilting improved fiber digestibility and was associated with changes in ruminal contents and fermentation end products. Wilting appears to be more effective than inoculation as a postharvest management tool to improve small grain silage. © 1995, American Dairy Science Association. All rights reserved

Dietary Proteins as Determinants of Metabolic and Physiologic Functions of the Gastrointestinal Tract

Dietary proteins elicit a wide range of nutritional and biological functions. Beyond their nutritional role as the source of amino acids for protein synthesis, they are instrumental in the regulation of food intake, glucose and lipid metabolism, blood pressure, bone metabolism and immune function. The interaction of dietary proteins and their products of digestion with the regulatory functions of the gastrointestinal (GI) tract plays a dominant role in determining the physiological properties of proteins. The site of interaction is widespread, from the oral cavity to the colon. The characteristics of proteins that influence their interaction with the GI tract in a source-dependent manner include their physico-chemical properties, their amino acid composition and sequence, their bioactive peptides, their digestion kinetics and also the non-protein bioactive components conjugated with them. Within the GI tract, these products affect several regulatory functions by interacting with receptors releasing hormones, affecting stomach emptying and GI transport and absorption, transmitting neural signals to the brain, and modifying the microflora. This review discusses the interaction of dietary proteins during digestion and absorption with the physiological and metabolic functions of the GI tract, and illustrates the importance of this interaction in the regulation of amino acid, glucose, lipid metabolism, and food intake

35. Visualizing the Effects of Light Pollution on the Local Night Sky

Recently there has been a lot of concern about the loss of our night sky. The growth of towns and cities creates an ever-encroaching threat of light pollution. The University of North Georgia’s Observatory is very much affected by this threat as new services and facilities are built closer in proximity to Dahlonega, Ga. When people try to find information about the local light pollution, they are most likely to find a light pollution map online. These maps are generally depicted as a top down view of the Earth. However, we believe this does not provide an intuitive understanding of the threat. We wish to provide a different perspective that allows people to better comprehend the damage to our local sky. We have begun constructing a device to measure a 360-degree view of the light pollution affecting the local night sky. We are currently designing and manufacturing a mount that can accurately survey the entire sky and record data from a sky quality measurement device. From this data we will build a map showing the effects of light pollution. We will use this map in an educational setting like UNG’s Cole Planetarium to promote local dark sky conservation efforts, and the data will be accessible for students with an astronomy focus to plan out the best possible times for quality observations once the new UNG Observatory is finished

Regulation of intestinal glucose absorption: A new issue in animal science

Intestinal glucose absorption occurs via Na+-dependent glucose cotransporters (SGLT1) located in the luminal membrane of enterocytes and is driven by an electrochemical gradient maintained by Na+/K+ ATPase located on the basolateral membrane. Twenty percent of whole animal energy expenditures can be accounted for by the gastrointestinal tract, most of which is the result of Na+/K+ ATPase function. Active intestinal glucose transport is regulated by a number of gastrointestinal peptides such as epidermal growth factor (EGF) and peptide YY (PYY). PYY and EGF can upregulate intestinal glucose absorption by as much as 200-300%. Of special interest is the fact that the energetic costs of intestinal tissue function can vary in relationship to the amount of glucose transported. This value termed "apparent energetic efficiency of glucose uptake" (APEE) may be of value in evaluating the energetic costs of glucose and other nutrients during various physiological and nutritional states. Recent studies suggest that intensive genetic selection for production traits in poultry may result in intestinal absorption being rate-limiting for full phenotypic expression of these traits. Further research is needed to clarify this issue

Undegraded intake protein: Effects on milk production and amino acid utilization by cows fed wheat silage

Thirty-six Holstein cows in second or later lactation were used in a 63-d completely randomized block design to determine the effects of RUP source on milk production, composition, and estimated AA uptake by the mammary gland. Cows were divided into 12 blocks of three cows each based on DIM (54.5 d) and milk production. Treatments were 1) soybean meal; 2) treated SBM; and 3) supplemental protein from TSBM, corn gluten meal, and Menhaden fish meal with each protein supplying equal amounts of CP. Mean DMI was greater for cows fed supplemental RUP. Intake of RUP was increased by 0.5 and 0.4 kg d-1, respectively, for treatments 2 and 3. The NEL intake was greater for cows fed treatment 3 than for those fed treatment 2. RUP supplementation increased BW accretion and milk production. Milk composition was unaffected except for lactose, which was higher for milk from treatment 3 than for milk from treatment 2. Extraction efficiencies of AA indicated that the supply of Met and Lys to the mammary gland was first and second limiting for cows receiving treatments 1 and 2 but colimiting for cows fed treatment 3. Results indicate performance differences related to RUP sources and specifically the amounts of Lys and Met available for metabolism