Influence of type of diet and incubation time on in sacco release of Cu, Fe, Mn and Zn from Italian ryegrass, untreated and ammonia treated wheat straw.

Artificially dried ryegrass, untreated and ammonia-treated wheat straw were ground and incubated in nylon bags in the rumen of three sheep each fed with diets based on roughage or concentrate. Dry matter degradability, the concentration and the release of the trace elements Cu, Fe, Mn and Zn from the incubated feeds were measured after 0 (washing loss), 6, 12, 24, 48 and 72 h rumen incubation time. Dry matter degradability, trace element concentration and their release were significantly influenced by the kind of incubated feeds, incubation time and feeding of sheep.

Nickel--an essential element.

Nickel is necessary for the biosynthesis of the hydrogenase, carbon monoxide dehydrogenase, and of factor F 430, found in a number of genera of bacteria. Urease from jack beans and several species of plants is also a nickel protein. These plant enzyme systems can affect animals via the microbiological digestion of food in the rumen.

[The supply of wild ruminants with major and trace elements. 2. The manganese content of winter grazing and the manganese status of red deer, fallow deer, roes and mouflons].

The winter grazing of wild ruminants on mantles of slate waste in the Harz mountains and in Gera county were richest in Mn whereas those on mantles of granite waste in the Erzgebirge were poorest. The flora of the shell-limestone, keuper and loess areas contains much less Mn than that of those acid habitats. The Mn-requirement of the wild ruminants grazing in the forests is met however, since bilberry plants (2,080 mg/kg), spruce twigs (984 mg/kg), spruce bark (827 mg/kg), oak twigs (791 mg/kg) and heather (754 mg/kg dry matter) in addition to many other plant species store extremely high amounts of Mn.

[The supply of wild ruminants with major and trace elements. 1. The cadmium content of winter grazing and the cadmium status of red deer, fallow deer, roes and moulons].

The Cd-determination of 10 different winter grazings for wild ruminants in seven different biotopes showed significant differences of the habitats resulting from the previous Cd-emission of metallurgy smelting non-ferrous metals. The winter grazing of the Tharandt Forest and the Harz mountains contained significantly more Cd than that of the Lower Flaming hills, the western Erzgebirge and the northern agrarian areas. The bark and the tips of conifer twigs, twigs of oak and mountain ash, bilberry and heather plants, i.