Auswirkungen einer Abwasserverregnung unter Kiefer auf den Nährstoffhaushalt eines Sand-Braunerde-Podsols

Zusammenfassung An Versuchen über Abwasserverregnung bis zu 1000 mm pro Winter in einem 80j?hrigen Kiefernbestand auf Sand-Braunerde-Podsol wurden Auswaschung und Vorrats?nderungen im Boden für C, N, P, die austauschbaren Kationen Na, NH₄, K, Ca, Mg, Al sowie die Metalle Cd, Co, Cr, Cu, Ni, Pb, Fe und Mn ermittelt. Auf Grund der Versuchsergebnisse werden Empfehlungen zur Abwasserverregnung in Waldbest?nden auf Sand-Standorten gegeben.

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Effects of sewage disposal in a pine forest on the nutrient balance of a sandy brown podzol soil

Summary Experiments on sewage disposal up to 1000 mm have been carried through in a 80 year old pine forest on a sandy podzolic soil. Input, percolation output and storage changes in soil were determined for C, N, P, exchangeable cations Na, NH₄, K, Ca, Mg, Al as well as Cd, Co, Cr, Cu, Ni, Pb, Fe and Mn. On the base of the results recommendations are given for sewage disposal in forests on sandy soils.

     

Micromorphology, chemistry, and mineralogy of bog iron ores from Poland

The influence of different land use history on the chemistry, mineralogy, and micromorphology of bog iron ores was studied in the vicinity of Warsaw, Poland. At three Holocene terraces of the Vistula River, eight profiles were chosen, which represent three different types of bog iron ore: (i) continuous hard layers (meadow, fallow at Wilanow), (ii) horizons with small ore fragments (arable land at Northern Praga), and (iii) soft bog iron ore (exploitation area at Brwinow). Chemical analyses of all bog iron horizons show a high content of Fe_d (up to 51%) with a Fe_o/Fe_d ratio from 0.19 to 0.58, indicating a mixture of crystalline iron and amorphous iron compounds. X-ray diffraction (XRD) analyses confirm the presence of ferrihydrite and goethite. The micromorphology of the bog ore at Wilanow shows a porous (vugh and channel) microstructure. The groundmass consists mainly of fine iron hydroxides. Compound coatings of radial distributed goethite needles and isotropic (“amorphous”) iron hydroxides line the pores. In many cases, several coatings of isotropic iron hydroxides, differing in colour intensity, fill the pores. Ploughing and draining at Northern Praga changed the continuous bog iron ore into small fragments embedded into an aggregate structure. It comprises of amorphous as well as crystalline iron compounds (large number of coatings of radial fibrous goethite in pores and channels). In some cases, a single pore can contain several generations of crystalline goethite. The higher crystallinity of the iron oxides fits very well to the lower Fe_o/Fe_d ratios compared to Wilanow. The differences can be attributed to the drainage, subsequent lower groundwater level, and better aeration, respectively, at Northern Praga. No hard bog iron ore is present at Brwinow because of exploitation, sporadically fragments of hard bog ore may be encountered in the topsoil. However, soft bog ore is still developing in subsoils. It shows a vughs microstructure. Besides goethite, manganese impregnations on the crystalline forms of goethite, and isotropic iron compounds, its groundmass also contains vivianite as well as siderite. The latter can be attributed to a more reductive environment.     

Techniques and strategies for the reduction of ammonia emission from agriculture

Agricultural production systems are recognised as a major source of atmospheric ammonia (NH₃). When deposited, the NH₃ may contribute to eutrophication of oligotrophic ecosystems and to acidification. Techniques for the reduction of ammonia emission are mainly focused on reducing the NH₃ emitting area exposed to the air, reducing the NH₃ or ammonium (NH ₄ ⁺ ) concentration in solution or reducing the exchange of air above the emitting surface. In this paper we present the techniques and changes in farming practice which may reduce NH₃ emission. Due to interactions between different sources on a farm, reduction in NH₃ emission from individual parts of the livestock production system cannot simply be added to give the net reduction in emission from the total system. Thus a whole farm system approach is needed for devising control strategies for reducing NH₃ emission.     

Die Differenzierung der Oberflächenzellinie im Labmagen adulter Rinder * The Differentiation of the Surface Mucous-cell Line in the Abomasum of the Adult Cow

The differentiation of the surface mucous-cell lineage during physiological cell renewal was investigated using light and electron microscopy in the abomasal mucosa of adult cattle. The surface mucous cells constitute a morphologically and functionally heterogeneous population, whose members correspond to different developmental stages, arranged in a distoproximal gradient from the depth of the pit towards the free luminal surface. The cell lineage comprises immature pre-pit cells near the proliferative isthmus, mature pit cells within the foveola, and older interfoveolar cells lining the free surface. Ultrastructurally, differentiation can be traced towards a predominantly mucus-producing cell type and finally towards a surface-protective cell variant, which degenerates in situ and is extruded into the lumen without affecting epithelial integrity.     

A survey of farmers'' attitudes to services provided by consulting veterinarians to the Western Australian sheep industry

A postal survey was conducted of 80 sheep farmers in the Kojonup and Esperance districts of Western Australia to establish what they wanted from a veterinary service. Twenty five of the farmers surveyed used a sheep consultant, 25 did not, and 30 were interested in employing one. Farmers were asked questions about themselves and their attitudes to private veterinarians who provide specialist services to sheep farmers. Data reported here showed that farmers wanted a veterinarian who lived in the district, was well trained in sheep management and production, was enthusiastic and had good communication skills. The service provided should be whole-farm and available to members of the consultant's group only. Regular newsletters and field days were necessary, but the provision of contract services, such as mulesing, lamb-marking, drenching, pregnancy testing and sheep classing, and 'fire-brigade' services for sick animals, were not rated as important. Most farmers were unwilling or unable to give a dollar value for the likely benefits of a consultancy service. Non-financial benefits included keeping farmers up to date with new technical developments and information. The survey also showed that a veterinarian specialising in services to sheep farmers could be confident of employment.     

Resistance to benzimidazole anthelmintics in small strongyles (Cyathostominae) of horses in Denmark.

This study was undertaken to establish whether anthelmintic resistance was present in nematode parasites of horses in Denmark. Sixteen horse farms were selected for faecal egg count reduction (FECR) tests to measure the efficacy of the anthelmintic used. Resistance to benzimidazole anthelmintics was found on 13 of the 16 farms, with FECR values ranging from 80.0% to -101.3%. On the remaining 3 farms FECR was 100.0%, 99.3% and 97.2%. Results of a questionnaire study on anthelmintic usage, parasite control measures and management practices showed that horses in this study were treated on average 7.1 times/year. Horse owners changed between preparations of drugs but almost only within the same class of anthelmintics. Nine owners gave an anthelmintic treatment to purchased horses before they were introduced on the farm. On 14 farms, the same paddock was grazed every year and the average stocking rate was estimated to be 2.4 horses/ha. Strategies to avoid development of anthelmintic resistance are discussed and recommendations of parasite control on horse farms are presented.     

Correlation between radiographie and arthroscopic findings in the equine carpus

The radiographic and arthroscopic findings in 150 carpal joints in 114 lame horses were compared. Chip, slab, or sagittal fractures were identified in 130 (87%) joints. In 101 (78%) of these there was good agreement between radiographic and arthroscopic findings on the number and position of fractures. In 23 (18%) joints, chip fractures additional to those seen radiographically were found arthroscopically. In one joint a large chip fracture from the craniolateral aspect of the distal radius was identified only by arthroscopy, while in 6 joints fractures were identified only by radiography. Observed causes of lameness, other than intra-articular fractures, included degenerative joint disease, synovitis, ruptured intra-carpal ligaments, and haemarthrosis. Correlation between the radiographic and arthroscopic assessment of degenerative joint disease was poor. It was concluded that both radiography and arthroscopy should be used to obtain the most accurate assessment of the equine carpus.     

Effects of the β-Adrenergic Agonist Cimaterol on Growth and Carcass Quality of Monozygotic Friesian Young Bulls at Three Developmental Stages

The objective was to investigate the effects of the β-adrenergic agonist cimaterol (CIM) on growth and carcass quality of Friesian young bulls at different developmental stages. The study comprised three liveweight groups (WG) each of four pairs of monozygotic twins. The average initial liveweight (LW) of the animals in WG 1, 2, and 3 was 162, 299 and 407 kg, respectively. One animal of each pair was fed 0.056 mg CIM per kg LW for 90 days, while the other served as a control (C). The animals were fed concentrate and barley straw according to LW and restricted to 80-90% of the ad libitum level of intake. The animals were slaughtered on day 90 of the treatment period. Without affecting feed intake, CIM treatment increased average daily gain (ADG) by 19% (P<0.001) and thus improved feed efficiency (P<0.001). Dressing percentage, carcass gain, EUROP conformation and longissimus dorsi area were all increased (P<0.001) after CIM treatment. Carcass length (P<0.01), backfat thickness (P<0.05), and internal fat (P<0.001) were reduced after CIM treatment, whereas organ weights were only marginally reduced. Weights of all of 14 different commercial cuts were increased (P<0.002), the increase was largest in cuts from the hind region of the carcass. The percentage of carcass saleable meat increased (P<0.001) in CIM-treated animals. The effects of cimaterol were evident in all three WG. The results show that cimaterol is effective in stimulating overall growth performance and improving carcass leanness of young bulls at different developmental stages, and concomitantly reducing fat deposition in general.