Larix intermedia — ein bemerkenswerter Lärchenbastard

European Journal of Forest Research -     

Black soil blindness: A new mycotoxicosis of cattle grazing Corallocytostroma-infected Mitchell grass (Astrebla spp)

A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named ‘black soil blindness’ because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease is present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.     

Dissolved nitrogen supersaturation of a heated effluent

A three month experimental study to evaluate the relative performance of three different designs of ‘event’ precipitation chemistry samplers was carried out at Woodbridge, Ontario beginning in August 1979. The samplers evaluated were an automatic Aerochem Metrics, ‘wet-only’ type (A), a funnel-and-bottle type (F), and a large-mouth plastic bucket with a specially-fabricated polyethylene bag insert (S). Each sampler was run in duplicate, with a sampling period of 24 hr. The results show that at sites where dry deposition is important, bulk samplers (‘F’ and ‘S’ types) yield significantly different results from the wet-only collector including rainfall amount, H⁺ , SO₄ ^?, NO₃ ^?, Na⁺, K⁺, Ca⁺⁺, and Mg⁺⁺. However, the bulk samplers, especially the ‘S’ type, are found to be satisfactory under certain conditions. For conditions which correspond to daily rainfall less than 2.8 mm and windier and drier sampling, there is even evidence of dry contamination of the wet-only type sampler.     

Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene

Thirteen strains of Streptococcus equi subsp. ruminatorum from free-ranging spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli) in Tanzania were characterized by biochemical and molecular-biological methods. Although the colony appearance of the S.e. ruminatorum wildlife strains differed from that of the S.e. ruminatorum type strain CECT 5772(T), all biochemical reactions of the wildlife strains were similar to those of the type strain. In addition, all wildlife strains produced hyaluronidase and were capable of hydrolysing arginine, three strains (23%) synthesized acetoin, but only eight strains (62%) produced acid from ribose. rep-PCR indicated that different clones of S.e. ruminatorum were distributed among the hyena and zebra populations in the study area. Identical rep-PCR patterns in hyena and zebra strains suggest that a direct transmission of S.e. ruminatorum between these species may occur. The presence of a M-like protein (SrM) gene was demonstrated in all S.e. ruminatorum strains including the type strain. Sequencing of the M-like protein gene revealed a hypervariable region within the deduced amino acid sequence. Most of the strains clustered with previously described strains based on the hypervariable region of the S.e. zooepidemicus SzP protein. Sequencing also demonstrated that identical SrM protein sequences were shared among S.e. ruminatorum strains from different host species.