227 research outputs found
Phosphatic Urinary Calculi
Many questions as to the cause, prevention and treatment of urinary calculi remain yet unanswered. However, many experiments the past several years provide a basis for a greater understanding of this problem and its control
Limestone As a buffering Agent in High-Concentrate Diets
In recent years, there has been evidence indicating that limestone in excess of normal requirement levels for calcium has beneficial effects for ruminants. Research at this station has shown that limestone supplementation is effective in preventing phosphatic urinary calculi formation in ruminants when fed at higher levels than normally recommended. Work at other stations has shown positive effects on weight gain from limestone added to highconcentrate diets, which was attributed to buffering action within the digestive tract. In short-term finishing periods, buffer supplementation may help ruminants adapt to high-grain diets if roughage has been their major feedstuff in the past. Graded levels of limestone were fed in this experiment to determine beneficial effects in protecting lambs from the effects of rumen acidosis during an extremely short adaptation period and to determine the optimum level of supplementation needed to improve performance during the longer term finishing period
The Use of Bentonite as a Feeding Aid for Ruminants
The beneficial as well as the potential detrimental effects of bentonite upon feedlot performance during as initial period and subsequent intervals of a lamb finishing period were studied in experiment 1. The effects of bentonite upon digestion and retention of various nutrients were studied in experiment 2. These studies are described herein
Sodium Bentonite and Sodium Bicarbonate in High-Concentrate Beef Cattle Diets
Sodium bentonite and sodium bicarbonate alter conditions in the rumen and may offer animals protection from some of the harmful effects of rumen acidosis. The potential benefits that may be derived from use of these materials have become increasingly important as backgrounding periods are extended and finishing periods are shortened. The experiment reported herein were designed to investigate the effectiveness of these materials, individually or in combination, in the adaptation of beef cattle to high-concentrate diets
Pre- and Post-Adaptation Effects of Buffers in High-Concentrate Lamb Diets
A gradual increase in grain cover a period of 2 to 4 weeks is commonly required before ruminant animals become adapted to high-concentrate diets. Various dietary materials including sodium bicarbonate, sodium betonite, limestone and forage have been indicated as potential adis in the prevention of acidosis during adaptation. Benefits from feeding of these materials following adaptation have been less pronounced or lacking. Objectives of studies reported herein were (1) to investigate the effects of buffers and limited quantitites of alfalfa hay on physiological and rumen fermentation changs occuring in lambs during the early phase of adaptation to high-concentrate diets and (2) to study ruminal and systemic parameters and nutrient utilization as influenced by buffers in the diets of lambs previously adapted to the high-concentrate diet
Nitrate and Vitamin A Interrelationship in Sheep
Several researchers have demonstrated that dietary nitrate reduced liver stores of vitamin A in ruminants. However, it has not been shown whether the effect is due to a more rapid depletion of existing vitamin A stores or to a lowered depatic deposition of the vitamin. Two experiments were conducted to determine the effect of nitrate on plasma vitamin A, hepatic vitamin A and performance of lambs during a growing period (experiment 1) and vitamin A depletion and repletion periods (experiment 2)
Effect of Various Chlorides and Calcium Carbonate on Calcium Phosphorus, Sodium, Potassium and Chloride Balance and Their Relationship to Urinary Calculi in Lambs
Various salts have been used in ruminant rations in attempts to reduce the incidence of urinary calculi. The relative effectiveness of 0.5 and 1.5% levels of ammonium chloride, calcium chloride, sodium chloride and calcium carbonate for the prevention of urinary calculi in sheep has been reported previously (South Dakota Sheep Field Day Reports, 1965). The studies reported herein were conducted to further determine the edegree of protection afforded sheep against urinary calculi by the feeding of various salts, and to determine their effect on excretion and retention of the minerals
Midlatitude, Rayleigh-Mie-Raman Lidar for Observations from 15 to 120 km
Rayleigh lidar opened a portion of the atmosphere, from 30 to 90 km, to ground-based observations. Rayleigh-scatter observations were made at the Atmospheric Lidar Observatory (ALO) at Utah State University (USU) from 1993–2004 between 45 and 90 km. The lidar consisted of a 0.44-m diameter mirror, a frequency-doubled Nd:YAG laser opera\u27ng at 532-nm at 30- Hz at either 18- or 24-W, giving power- aperture products (PAPs) of 2.7- or 3.6- Wm2, respec\u27vely, and one detector channel. An example of what was accomplished with this system is shown as part of Fig. 1. The temperature climatology was based on ~5000 hours of observa\u27ons carried out over ~900 nights. The temperatures, with 3-km al\u27tude resolu\u27on, were averaged over periods of 31 days by 11 years.
The ALO Rayleigh lidar is currently being upgraded, as indicated, as indicated in Fig. 1, to extend observations upward into the lower thermosphere and downward to the lower stratosphere
Rayleigh Lidar Temperature Studies in the Upper Mesosphere and Lower Thermosphere
Rayleigh lidar technology opened the middle atmosphere (from 30–90 km) to ground-based observations. The upgraded system at the Atmospheric Lidar Observatory (ALO) on the campus of Utah State University (41.74, 111.81) has shown that these ground-based observations can be extended to 109 km, with the goal of reaching 120 km. The resultant study of short and long-term temperature trends, using Rayleigh lidar, contributes immensely to the overall understanding of the properties and dominant physical processes in the middle atmosphere and Mesosphere-Lower Thermosphere (MLT) region. Temperature variations on short time scales, from minutes to days, give insight into the effects of waves (gravity waves, tides, planetary waves), while climatological studies of temperatures can help in the study of global change throughout the atmosphere
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