Phänotyp und Futterqualitat einschliefilich Konservierungseigenschaften bei Grasern

Phenotype and forage value, including conservation properties, of grasses The phenotype of grasses can be influenced by the date of harvest as well as by breeding programs. In contrast to dicotyledons, the stems of grasses are younger than the leaves, although the grass leaves are usually considered to have a higher nutritional value than the stems. In a field experiment, Lolium multiflorum Lam. ssp. gaudini (Parl.) Schinz et Kell. was grown as a model-plant in order to study effects of ploidy-level, N-fertilization, stage of development, and growth time on the main aspects of nutritional value and conservation properties in relation to the phenotype. As regards the nutritional value, the interactions of ploidy × plant organ (=stem or leaf) and of ploidy × N-input were not significant. Hence, the results for leaf and stem can be generahzed. Until the emergence of the inflorescence, EC 49, the stem showed a significant higher net energy content than the leaf; at later stages of development this relationship changed. The evaluation of the net energy content of leaf and stem was significantly influenced by the method of estimation. In vitro methods with rumen liquor may show the best approximation to the real value. The crude protein/energy ratio of the stem as compared to the leaf better meets the nutritional requirements of ruminants; on the other hand the leaf was more valuable than the stem in relation to the nitrate content, especially when the whole plant showed an increased nitrate level. The general relationship between the mineral content and the phenotype was not evident. The investigation indicated significant differences between stem and leaf in relation to their conservation properties. The leaf showed more favourable drying properties than the stem but ensilability was better for the stem than for the leaf. As a result of this investigation it is assumed that, in the past, the nutritional value of young stem has been underestimated whereas the value of the leaf has been overemphasized. This may also be due to the criteria and determination methods of the nutritional value.     

Sortenbedingte Reaktion bei Lolium perenne L. auf systemisch selektiv wirkende Herbizide

Variety-specific reaction of Lolium perenne L. on selective systemic herbicides
The investigation intended to show the specific reaction of different varieties of Lolium perenne on selective systemic herbicides. These results can be regarded as the base for advanced explorations to the described topic. The results may be summarized as follows:
Independent of the stage of growth, the date of application, the dosage and the droplet size there were effects on the forage yield in correlation to the variety and the active ingredient. Measurable yield reductions were presented after CMPP application on the varieties of the late and after the treatment with Asulam on the varieties of the early maturity group. Compared to the maturity group the varietal attribute growthhabit demonstrated no significant effects. The active ingredients MCPB and MCPA presented not any measurable influence on the forage yield of the different varieties. In the main harvest year the yield depressions were manifested clearer than in the seeding year. In the same way the described secondary actions were larger after the treatment in an advanced stage.
Extended investigations should inquire to the causes and secondary effects on the forage quality. Beyond this for variety testings of species with a large distribution and volume it seems remunerative to include questions of herbicides tolerance.     

Indirect micro-enzyme-linked immunosorbent assay for the detection of antibodies to Mycoplasma synoviae and M. gallisepticum

The sensitivity and specificity of the indirect micro-enzyme-linked immunosorbent assay (ELISA) was compared with that of the rapid serum-plate test (RSPT) and the hemagglutination-inhibition test (HIT) in detecting antibodies to Mycoplasma gallisepticum (MG) and M. synoviae (MS). Membrane antigens of MG strain S6 and MS strain NEL 61800 were used. ELISA was performed with single MS and single MG antigens and a combined MS/MG antigen. The MS-ELISA was as sensitive as the MS-RSPT and more sensitive than and as specific as the MS-HIT in detecting antibodies to MS. The MG-ELISA was less sensitive than the MG-RSPT and slightly less sensitive than the MG-HIT in detecting antibodies to MG in chickens experimentally infected with MG R strain but more sensitive in detecting antibodies in chickens infected with MG F strain. MG-ELISA resulted in fewer cross-reactions than the MG-RSPT but more than the MG-HIT. The combined MG/MS-ELISA was as sensitive as the ELISA with its individual antigen components. No nonspecific reactions were observed with sera from MG/MS-free flocks. The combined MG/MS-ELISA was found to be a practical screening test for antibodies to both MS and MG. Further improvement of the sensitivity and the specificity of the MG antigen is desirable.     

Prediction of digestibility and energy concentration of winter pasture forage and herbage of low-input grassland--a comparison of methods.

Regarding the estimation of the energy concentration or digestibility of herb-dominated forage and plant samples from winter pastures, it could be expected that the estimation is only reliable when in vitro methods with rumen fluid as inoculum (= gas production techniques) are used. For the verification of this thesis based on logical reflections, an in vitro-method with rumen fluid added as inoculum, as well as chemical, and enzymatic methods were applied under consideration of existing estimating functions. As a possible reason for the observed divergence of the methods, effects of fungal infections or, respectively, secondary compounds in herbs are discussed. At the present state of knowledge, it is adequate to estimate the energy concentration in vitro by gas tests, as far as fattening types like suckler cows and beef cattle are concerned, maybe in contrast to the forage evaluation for dairy cows.