Because grains comprise the major portion of diets for finishing beef cattle, and grains contain little calcium, limestone is typically added to finishing diets at levels of .7 to more than 1% of the dry matter. Feedgrade limestone varies in quality and consistency, which could alter performance responses by finishing beef steers. Selection of superior sources of limestone and(or) treatment of ...

In recent, the placement of backfill in underground mines has emerged as a new paradigm in research as it not only improves safety but also allows disposal of byproducts including coal ash. In this regards, this paper addresses the backfilling challenges in limestone mine to prevent sinkhole and subsidence. Limestone mines, generally regarded as being safer than coal and metal mines, have been ...

Two experiments were conducted to compare a sample of calcium citrate-malate (CC-M) with a sample of commercial-grade limestone in starting broiler chick diets. In the first experiment, with 0.7 or 0.9% calcium from limestone or CC-M, no differences in bone development (dry fat-free tibia, tibia weight, tibia ash, or tibia calcium) were observed due to calcium source. However, chicks fed the di...

Caves pose significant challenges for mining projects, since they harbor many endemic and threatened species, and must therefore be protected. Recent discussions between academia, environmental protection agencies, and industry partners, have highlighted problems with the current Brazilian legislation for the protection of caves. While the licensing process is long, complex and cumbersome, the ...

A 112-day trial was carried out to evaluate the effect of dietary calcium level and limestone particle size on the egg quality of 288 HyLine Brown semi-heavy layers, with 83 weeks of age at the beginning of the experiment. A completely randomized experimental design was applied in a 2x3 factorial arrangement, with two dietary calcium levels (3.5 and 4.0%) e three limestone particle size composi...

Limestone dust is generally regarded as being relatively harmless. In this paper I wish to record eight cases of pneumoconiosis in limestone workers, in all of which limestone played the sole or principal aetiological part. My attention was first drawn to the condition in November, 1950, when I saw the chest radiograph of a patient whose occupation was limestone crushing. The appearances were m...

Acidic mine drainage (AMD) containing elevated concentrations of dissolved iron and other metals can be neutralized to varying degrees by reactions with limestone in passive treatment systems. We evaluated the chemical and mineralogical characteristics and the effectiveness of calcitic and dolomitic limestone for the neutralization of net-acidic, oxic, iron-laden AMD from a flooded anthracite m...

Lithistid demosponges are well known from limestone caves of karstic origin in the Mediterranean Sea. However, they have never been reported submarine volcanic South Pacific. Here, we describe and provide DNA barcodes for four new lithistid including one genus. All species grew on basaltic rocks inside lava tubes Nuku Hiva Island (Marquesas Islands) Tahiti Iti peninsula (Society French Polynesi...

Effects were evaluated of high dietary levels of magnesium oxide (MgO) or limestone on DM, OM and CP digestibility, N balance and intestinal absorption of amino acids by lambs fed a high concentrate diet. Twelve wether lambs equipped with abomasal and ileal cannulas were blocked by weight and breeding and allotted to treatments in a randomized block design in two consecutive trials. Diets were ...

except in a few extremely arid regions. Figure 1 shows the variety of sources for the water responsible for the development of caves. Most of the caves are dissolved by the movement of groundwater in contemporary drainage basins. In coastal regions, the mixing of fresh groundwater with saltwater produces an aggressive solution that can dissolve out caves. Some caves (for example, the large cave...