Time filter

Source Type

Kromker V.,Hanover University of Applied Sciences | Pfannenschmidt F.,Chamber of Agriculture Lower Saxony | Helmke K.,Osnabruck University of Applied Sciences | Andersson R.,Osnabruck University of Applied Sciences | Grabowski N.T.,University of Veterinary Medicine Hannover
Journal of Dairy Research | Year: 2012

The prevalence of intramammary infections (IMI) and subclinical mastitis (SCM) in 436 German Holstein heifers was put in relation with clinical findings of the udder and data regarding individual rearing and housing conditions of the animals. The clinical examination took place on the day of the livestock auction (at approximately 41 d in milk, DIM). On that day, 31% of the heifers had IMI in at least one quarter, and 18% of all quarters were infected. Coagulase-negative staphylococci were the most prevalent bacteria isolated, accounting for 68% of the positive samples. Data were analysed by logistic regression. Criteria such as 'juvenile intersucking', 'teats shorter than 35 mm', 'teats with a diameter <18 mm' and 'udder oedema at the day of the auction' were associated with IMI in heifers during the first 41 DIM. Loose-housing systems during pregnancy (as opposed to tie-stalls), juvenile intersucking, clinical mastitis during the first week after calving, teat diameters <18 mm, and employing organic bedding material in the stables before calving were associated with subclinical mastitis. © Proprietors of Journal of Dairy Research 2012.


Wolfarth F.,Johann Heinrich Von Thunen Institute | Schrader S.,Johann Heinrich Von Thunen Institute | Oldenburg E.,Julius Kuhn Institute | Weinert J.,Chamber of Agriculture Lower Saxony
Soil Biology and Biochemistry | Year: 2013

Despite well-known positive aspects of conservation tillage combined with mulching on arable fields, one drawback may be the survival of phytopathogenic fungi on plant residues. Therefore, plant pathogen repression is an important ecosystem service to prevent cultivated plants from fungal diseases and mycotoxin contamination. A microcosm-study was conducted under constant laboratory conditions to assess the impact of soil microfauna (Aphelenchoides saprophilus, Nematoda) and soil mesofauna (Folsomia candida, Collembola) on soil-borne phytopathogenic fungi (Fusarium culmorum) and its mycotoxin deoxynivalenol (DON). Our hypotheses were: (1) nematodes and collembolans reduce the biomass of F. culmorum and the content of DON in infected wheat straw; (2) the species interaction of A. saprophilus and F. candida enhances the degradation of Fusarium biomass and DON concentration in wheat straw; (3) the degradation efficiency of nematodes and collembolans is affected by soil texture. Therefore, microcosms were filled with soil of different texture and finely chopped wheat straw (Fusarium-infected vs. non-infected). The microcosms were inoculated with the two species in different combinations (single and mixed species, non-faunal control). After 2 and 4 weeks of incubation, the individual densities in all soil faunal treatments increased with highest individual numbers in the non-infected treatments in case of collembolans and in the infected treatments in case of nematodes. The Fusarium biomass (Fusarium protein equivalents = FPE) of all infected treatments decreased by at least one order of magnitude after 2 weeks. At the end of 4 weeks Fusarium-biomass was reduced by 93% in sandy and silt loam and 89% in clay loam mostly in mixed species treatments. Also DON concentrations were reduced significantly compared to the initial concentration in all treatments after 4 weeks. The highest reduction was found in mixed species treatments, where DON was degraded by 92%, 95% and 39% for sandy loam, silt loam and clay loam, respectively. We concluded that particularly interacting collembolans and nematodes play an important role in plant pathogen repression and mycotoxin degradation. In any case, soil texture matters in the provision of these ecosystem services by collembolans and nematodes. © 2012 Elsevier Ltd.


Wolfarth F.,Johann Heinrich Von Thunen Institute | Schrader S.,Johann Heinrich Von Thunen Institute | Oldenburg E.,Julius Kuhn Institute | Weinert J.,Chamber of Agriculture Lower Saxony
Mycotoxin Research | Year: 2011

In arable fields managed by conservation tillage combined with crop residue mulching, plant pathogen repression is an important ecosystem service to prevent cultivated plants from fungal diseases and mycotoxin contamination. A laboratory microcosm study was conducted to investigate the contribution of the endogeic, geophagous earthworm species Aporrectodea caliginosa as a secondary decomposer to the reduction of the phytopathogenic fungus Fusarium culmorum and its mycotoxin deoxynivalenol (DON) in wheat straw residues. After 5 weeks experimental time, the Fusarium biomass and the DON concentration in aboveground straw were reduced considerably to the same extent both in presence and absence of A. caliginosa. Another substantial reduction of Fusarium biomass and DON concentration was found in belowground straw, which A. caliginosa had buried into the soil. Thus, we conclude that the particular contribution of secondary decomposers like A. caliginosa to the degradation of phytopathogenic fungi like Fusarium species and their mycotoxins like DON in the soil systems has to be assessed as minor. © Society for Mycotoxin Research and Springer 2011.


Feller C.,Leibniz Institute of Vegetable and Ornamental Crops | Richter E.,Julius Kuhn Institute | Smolders T.,Limseeds BV | Wichura A.,Chamber of Agriculture Lower Saxony
Annals of Applied Biology | Year: 2012

BBCH [Biologische Bundesanstalt (Julius Kühn-Institut), Bundessortenamt, CHemische Industrie] scales are used in applied natural sciences for the description of phenological growth stages of plants and are available for many crops today. Currently, a specific BBCH scale for Asparagus officinalis, a perennial vegetable plant of worldwide interest, does not exist. In this study, an extended BBCH scale was developed, describing precisely the growth stages of A. officinalis. Nine principal growth stages were defined and subdivided into several secondary growth stages resulting in a two-digit decimal code. Detailed descriptions of the particular stages and illustrations were included to clarify the application of the code system. The scale is proposed to specify and harmonise research activities as well as to enhance comparability of crop management practices for growers of asparagus. © 2012 Association of Applied Biologists.


Wolfarth F.,Johann Heinrich Von Thunen Institute | Schrader S.,Johann Heinrich Von Thunen Institute | Oldenburg E.,Julius Kuhn Institute | Weinert J.,Chamber of Agriculture Lower Saxony | Brunotte J.,Johann Heinrich Von Thunen Institute
Soil Biology and Biochemistry | Year: 2011

A field experiment was conducted to elucidate ecosystem services provided by earthworms on the repression of phytopathogenic and toxinogenic fungi. The study focussed on decomposing Fusarium culmorum-infected and deoxynivalenol (DON)-contaminated wheat straw remaining on the soil surface as part in conservation tillage. Mesocosms were established in the topsoil of a winter wheat field located in Northern Germany, where conservation tillage has been practised for 20 years. Besides a non-earthworm treatment, two earthworm species were inoculated in the mesocosms either separately or combined: Lumbricus terrestris (anecic, detritivorous) and Aporrectodea caliginosa (endogeic, geophagous). The earthworms were exposed either to artificially Fusarium-infected wheat straw highly contaminated with DON or to non-infected straw serving as a control. The experiment was conducted during an eight week period after harvest from mid August to mid October. For both species, the artificially Fusarium-infected and DON-contaminated wheat straw was a more attractive food source than the non-infected control. In contrast to A. caliginosa, L. terrestris incorporated infected straw faster into the soil compared to control straw. Furthermore, the reduction of Fusarium biomass and DON concentration in wheat straw was significantly higher in the presence of L. terrestris than in treatments with A. caliginosa and without earthworms. Here, no significant differences could be measured between the Fusarium biomass and DON concentration in wheat straw. A. caliginosa seems not to be relevant for the reduction of Fusarium biomass and DON concentration. We concluded that amongst earthworms, anecic detritivorous species are the drivers to compensate possible negative consequences (like crop infection) of conservation tillage. They take an important role in the control of phytopathogenic and toxinogenic fungi surviving on plant residues and in the degradation of their mycotoxins. © 2011 Elsevier Ltd.


Abfalter K.,Leibniz University of Hanover | Brade W.,Chamber of Agriculture Lower Saxony | Distl O.,Leibniz University of Hanover
Archiv Tierzucht | Year: 2016

The present analysis compares the estimated breeding values (EBVs), relative breeding values (RBVs), and daughter yield deviations (YDs) of cows with exceptional longevity with their contemporary herdmates. In addition, the relative breeding values of their sires were compared among these two daughter groups; the RBVs of the sires were also compared with the proportion of their daughters with exceptional longevity. Data included 5037 sires born between 1963 and 1996 with a total of 61 988 daughter; of these sires, 486 had sired daughters that completed more than nine lactations (exceptional cows) and 4957 sires had sired the contemporary herdmates. Exceptional cows had on average significantly lower EBVs for milk yield, fat and protein yield, and significantly lower YDs for milk and protein yield in the first three lactations, significantly lower RBVs for milk production and type but significantly higher RBVs for somatic cell score and functional longevity. The sires of exceptional cows had significantly higher RBVs for somatic cell count (RZS), functional longevity (RZN), and fitness (RZFit) in comparison to the sires of contemporary herdmates. Correlations among the proportion of exceptional cows per sire and RZN, RZS as well as RZFit were positive, whereas milk production (RZM) showed a negative correlation. An increase in the number of cows with exceptional longevity may be possible through a relative total breeding value with high positive weights for RZN, RZS, and RZFit but negative weights for RZM and type (RZE). © Author(s) 2016.


Kayser M.,University of Gottingen | Benke M.,Chamber of Agriculture Lower Saxony | Isselstein J.,University of Gottingen
Agronomy for Sustainable Development | Year: 2011

Information on the environmental impact of maize production is actually inconsistent. Indeed some experiments report good nitrogen (N) efficiencies and small residual N. Other experiments show large leaching losses, while in practice maize production is often coupled with an intensive production and large N surpluses. Here, we present data from a 4-year experiment with silage maize on a sandy soil of high mineralization potential. The experimental set-up included three N input forms, mineral, cattle and pig slurry and four rates of total N, of 0, 80, 160 and 240 kg N ha-1 year-1 and the use of suction cups. Results show that dry matter and N yields for N0-N240 were relatively high and consistent (158-192 kg N ha-1). Further findings show large residual soil mineral nitrogen, of 138-237 kg Nha-1, and high nitrate concentrations in leaching water during winter, of 39-73 mg NO 3-N L-1, corresponding to leaching losses of 86-152 kg N ha-1. Response to N input was small with apparent N recoveries of 14-22% for manures and mineral fertilizers. We conclude that caution is needed when maize production is extended to fields with an apparently high potential for mineralization and that use as grassland would be a better alternative with regard to N leaching losses. © INRA and Springer Science+Business Media B.V. 2011.


Kayser M.,University of Gottingen | Breitsameter L.,University of Gottingen | Benke M.,Chamber of Agriculture Lower Saxony | Isselstein J.,University of Gottingen
Agronomy for Sustainable Development | Year: 2014

The return of slurry is the most important means of fertilization in grassland dairy farming. Broadcast application of slurry induces air pollution by ammonia. Alternatives to broadcast application like sliding shoe or injection have therefore been introduced. These alternatives might, however, cause higher N losses by nitrate leaching because N prevented from volatilization may not completely be utilized for dry matter production. Information on the interactive effects of amount of N input and slurry application technique on nitrate leaching from productive organic–sandy soils are still scarce. Therefore, we tested the hypothesis that slurry application by sliding shoe or injection leads to larger NO3-N losses via leaching than broadcast application. In a 4-year experiment on cut grassland, we applied N at 0, 160, 240, and 320 kg ha−1 year−1 using four application techniques: in the form of a chemical-synthetic N fertilizer or as cattle slurry applied broadcast, by sliding shoe or shallow injection. We assessed nitrate leaching during winter using suction cups. Additionally, we determined herbage dry matter yields, N offtake, and soil mineral N content to compile N balances for the individual treatments based on these data. Our results show that nitrate leaching during winter did not differ significantly among treatments of N application technique. Nitrate leaching increased significantly with increasing amount of N input, but was on average lower than 16.5 kg N ha−1 for application rates of up to 320 kg N ha−1. Soil mineral N content in autumn was a reasonably good predictor for nitrate leaching, with R2 of 0.65. The proportion of nitrate leaching of positive N surpluses increased in the order broadcast, sliding shoe, injection, and chemical-synthetic N application. Our findings demonstrate that the amount of N input but not the technique of application results in a significant effect on nitrate leaching. © 2014, INRA and Springer-Verlag France.


Kayser M.,University of Gottingen | Benke M.,Chamber of Agriculture Lower Saxony | Isselstein J.,University of Gottingen
Plant, Soil and Environment | Year: 2012

Relatively little is known about potassium leaching losses following harvest of silage maize. While direct negative impacts on the environment are unlikely, losses of K with leaching need to be known for accurate balancing, especially on coarse textured soils, where K can be a critical element. In a four-year field experiment the effects of fertilizer forms (inorganic, cattle slurry and pig slurry) and four levels of N input (0, 80, 160, 240 kg N/ha) with corresponding amounts of K on the nutrient balances and leaching of K from silage maize grown on a sandy soil were investigated using suction cups. After four years, surplus of K from cattle slurry led to higher lactate-soluble K in the topsoil. Potassium leaching differed between years with different amounts of rainfall during winter. Annual leaching losses of K increased with N and K input and amounted to 38 kg K/ha, while fertilizer form had no significant effect. Losses of K increased with increasing N leaching (R2 = 0.69). We conclude that in maize production on coarse textured soils and under conditions of high N leaching (86-152 kg N/ha), K leaching can be large (6-84 kg K/ha) and constitutes a relevant part of K balances (-84 to +127 kg K/ha).

Loading Chamber of Agriculture Lower Saxony collaborators
Loading Chamber of Agriculture Lower Saxony collaborators