Reactions of Reduced Glutathione with Some Methylated Selenium Compounds

Selenium biochemistry has been of general interest since the discovery of selenium as the toxic agent in certain plants, which when ingested by animals causes a definite disease syndrome and even death. Early scientists suggested that the logical place in the body for toxic selenium compounds to attack was at the various sites occupied by sulfur. In 1939 a study was published which indicated that reduced glutathione (GSH), a thiol, protected rats against death from a minimum fatal dose of selenium given as sodium selenite. Since this discovery, the reaction of GSH with various selenium containing compounds has been the subject of much research. Improved technology has led to new insights about the reaction of GSH with selenium compounds. This, coupled with recent advances in metabolite and toxicity studies, has led to the proposal of a pathway for the metabolism of selenium which involves the reaction of GSH with several methylated selenium compounds. The studies reported here have been done in an attempt to investigate those proposed reactions. Specifically, the reactions under investigation are: 1) The reaction of GSH with methylseleninic acid (CH3SeO2H), 2) The reaction of GSH with dimethyl diselenide (CH3SeSeCH3), 3) The reaction of GSH with dimethyl selenoxideCH3)2SeO]

Take an Accurate Forage Sample

Successful livestock production depends largely on the feeding program; and what you should feed depends on an accurate analysis of the forage portion of your ration. The accuracy of forage analysis depends on the sample that you send to the lab. Samples must be representative of the feeds being fed. Poor sampling will result in misleading values, higher feed costs, and reduced performance. In many feeding programs, the sample is the weak link. The results of the lab tests will be useful only if the sample accurately represents what your animals will be eating. Keep in mind that every field and every cutting will be different

Interpretation of Water Analysis for Livestock Suitability

This article contains a summary that analyzes the purpose of water for livestock suitability

Interpretation of Water Analysis for Livestock Suitability

Good quality water is essential for the production of livestock and poultry. In South Dakota, many water supplies have naturally occurring al that may limit their use. Livestock producers that test their water supply can make informed decisions about the stability of their water for different classes of livestock. The purpose of this guide is to assist livestock producers in the interpretation of their water analysis

Interpreting Hay and Haylage Analysis

Feed test results can be used to: (1) balance rations, (2) improve future crop management if present forage is of unsatisfactory quality, and (3) determine equitable prices for feedstuffs based on nutritive value. Results of analysis are expressed on an “as-received” and on a “100% dry matter (DM)” basis. As-received is sometimes also referred to “as-fed” or “fresh.” It includes the water or moisture in the feed. Nutrients expressed on this basis represent the nutrient content of the feed when it was received at the lab

Interpreting Corn Silage Analysis

Corn silage test results are of little value unless they are understood and used. Results can be used to balance rations and to improve future crop management if the test has shown the present forage is of unsatisfactory quality. Results of analysis are expressed on an “as received” and on a “100% dry matter (DM)” basis. As-received is sometimes referred to “as-fed” or “fresh.” The as-received basis includes the water or moisture contained in the feed. Nutrients expressed on this basis represent the nutrient content of the feed when it was received at the lab

Forage Value of Spring Oats and Triticale

Spring oats commonly are grown in South Dakota for either grain or forage. The value of oats as forage depends on maturity when harvested and varietal characteristics. As oats matures, yield increases and quality decreases. Research indicates that tall, late-maturing varieties produce the highest forage yields. Triticale was originally developed as a grain for human and animal consumption, but it has the potential to be used as forage. Research suggests that spring triticale has forage yield and quality characteristics similar to oats and barley

Forage Yield and Quality of Multileaflet Alfalfa

There has been interest among private companies in the past five years in producing multifoliolate or “multileaflet” alfalfa varieties. Conventional varieties have only three leaflets per leaf while multileaflet varieties may have plants that possess five, seven, or even nine leaflets per leaf. Although the multileaf trait of alfalfa has been known for more than 50 years, research has been limited. Recent interest has led to the development of about 10 multileaflet varieties. The promotion of these varieties has generated interest among forage and livestock producers in the potential benefits of these varieties over conventional varieties

Use a Microwave Oven to Determine Moisture Content of Forages

Knowing the moisture content of forages at the time of harvest and storage is essential for making and preserving high-quality hay and silage. Knowing the moisture content of stored forages is important for accurate ration formulation. A squeeze test, which involves squeezing forage into a ball and then guessing the moisture content, is a common method of determination. This method is rapid, but it lacks precision. Resistance-type moisture testers estimate moisture as a measure of electrical resistance. These devices provide estimates rapidly, but they usually are expensive (about $100 to$150) and vary in accuracy. A portable, electric drying unit also is available and is fairly accurate, but it requires at least 30 minutes before readings can be taken. Using a microwave oven to determine moisture content is advantageous because it dries forage in a minimum amount of time and can provide accurate results. The following procedure describes how to use a microwave oven for moisture determination. This is a good option for producers who do not want to purchase expensive moisture testers