Browsing by Subject "Belastung"

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DIE BEDEUTUNG DER LAUFAKTIVITÄT UND DER GEWICHTSENTWICKLUNG BEI DER ENTSTEHUNG VON BEINSCHÄDEN BEIM MASTGEFLÜGEL
(2006) Djukic, Mirjana; Bessei, Werner
Within the last 50 years, an intensive selection took place in broilers on high growth and therefore there exists a clear reduction of the age at slaughter. Side effects of the selection of faster and higher growth are leg disorders. RUTTEN et al. (2002) tried to reveal the causal relations between weight load, activity and leg disorders by reducing the weight load on legs of fast growing broilers (FB) by a special device. The weight reduced FB showed higher locomotor activity and better bone quality. However, the harness used for the reduction of weight load on the legs impaired the growth rate. In the present study, the experiment of RUTTEN et al (2002) was repeated with an improved device for reduction of weight load of FB. In addition, slow growing broilers (SB) were used, and were brought to the same weight load as weight reduced FB by additional load. In total three experiment were carried out. The first experiment was split in two parts (1a and 1b) so as to incrase the number of replicates. For each experiment, 24 male broilers were used: 12 FG (ROSS 308) and 12 SB (ISA S 257). Load reduced birds weared a harness which was connected to the load reducing device. The load increase of SB weared the same harness with small pieces of led. The chicks of the groups were treated as follows: one with harness and suspension (HS), one with a harness and without suspension ? control bird 1 (C1) and a control bird with no harness and no suspension ? control bird 2 (C2). The load of FB was reduced to the average weight of SB-C2 and FB C2. The load of the SB was increased to the same average value. The following parameters were recorded: body weight, food consumption, weight of breast muscle, thigh, tibiotarsus, femur; length of tibiotarsus and femur; angular deformity of distal femur, distal and proximal tibiotarsus; torsional deformity of femur and tibiotarsus, total area, total density, Corticalis area, Corticalis density, SSI, walking, sitting, standing, eating and ?other behavior?. The weight load reduction in FB led to a significant increase of the locomotor activity. Both the torsional and angular deformities of the Tibiotarsus were clearly reduced, while total area, total density, Corticalis area and SSI were increased. It can be assumed that this was caused by the higher locomotor activity of load reduced FB. The increase of load in the SB diminished the locomotor activity but bone characteristics were not deteriorated. The improvement in the bone conditions of the FB was obviously caused by the increase in activity. In order to determine the influence of decreased load in FB and of increased load in SB the opportunity to move was restricted by reduction of the length of the compartments from 2 to .45 meters. All other experimental conditions remained the same as in experiment 1. Despite the restricted space there was a significant increase in locomotor activity of the load reduced FB. The torsion and angular deformity of the proximal and distal angular deformities of the Tibiotarsus were reduced. There was no significant effect of the increase and decrease of load on the CT-criteria. As in experiment 1, the weight load in the SB diminished the locomotor activity, but the bone characteristics were not influenced significantly. In the third experiment the gait of the load increased SB and load decreased FB was analyzed by a foot print program. For this purpose the length and width of the steps were measured at 4, 5 and 6 weeks of age. The same breeds and the same technique of the modification of the load were used. The load treated birds were kept individually and could use the full length of the test pens. In contrast to the previous experiments the control birds were kept in pens of 1 m² floor space (1 x 1 m). Only the birds without harness (C2) were kept as control. The results of the morphometric and CT- criteria confirmed the results. The FB control birds showed higher step length and greater step width than SB controls. The step length of FB was increased through the load reduction, and decreased through load increase in SB. The treatment had no influence on the step width. SB broilers showed problems to keep their balance under increased weight load. As indicated in the low width of the foot prints the load increased SB broilers tried to place their feet, as usual, under the point of gravity of their body. This seems to impair the stability of gait under increased weight load. FB in contrast, move their centre of gravity above the supporting leg which allows a stable gait under high load. FB did not change the width of their foot prints when the load was decreased, and only the length of the steps increased. The results underline the importance of locomotor activity on the leg conditions of FB. They clearly show that low activity of FB is not caused by lack of motivation but by the high weight load.
Bürokratie in landwirtschaftlichen Betrieben : dargestellt am Beispiel von Milchviehbetrieben
(2013) Rothfuß, Kathrin; Doluschitz, Reiner
As in many sectors of the economy, state bureaucracy is regarded as an increasing und costly problem for individual agricultural businesses and for the agricultural sector as a whole. Coping with internal administration as well as the exchange of data as part of quality assurance programmes and based on contractual regulations are also growing in importance. It is no longer justifiable to question which administrative work is too time-consuming or unnecessary but rather how the inevitable bureaucracy can be dealt with as effectively as possible. The goal of this dissertation is therefore firstly to determine the administrative burden that exists for farmers and, secondly, to ascertain the factors that can affect the intensity of this burden or alleviate it. The bureaucratic burden will be ascertained in this dissertation on the basis of a subjective rating by farmers. A definition of the bureaucratic tasks to be evaluated by farmers was also needed in order to be able to define the bureaucratic burden. The criteria for this was that the tasks had to be relevant for dairy cattle farmers with arable farming in Baden-Württemberg. Furthermore, the analysed tasks had to be performed at least once per year and a certain level of work would be required for it. Quantitative and qualitative methods of empirical social research were combined to respond appropriately to the diversity of the aforementioned subject of this analysis. Dairy cattle farmers in Baden-Württemberg were surveyed in a multi-stage process. In the first step, 1,060 surveys were distributed to the participants of the milk recording. 487 farmers (46% return rate) responded to the standardised questions on the structure of their enterprise and their socio-democratic profile and rated the selected 45 bureaucratic tasks. 125 of these farmers agreed to a further interview. From these 125, 40 farmers were then selected for personal interviews based on defined criteria. These interviews were partially evaluated by qualitative methods and also include the questions contained in the subsequent telephone interviews. A further 82 farmers were surveyed by phone about their attitude towards bureaucracy. The factors that led to "very serious" bureaucratic mental burden were determined using a factor analysis and a subsequent binary logistic regression. The empirically recorded dairy cattle farms are above-average in size in terms of the number of dairy cattle and their total area. The burden felt is considerable. Almost half of those surveyed judge the burden caused by bureaucratic ("red tape") as being very significant and on average greater than other work-related challenges. Based on the rating of bureaucratic tasks, the "Gemeinsame Antrag" (application for subsidies) in first place and the recording of information concerning the use of veterinary drugs in second place are identified as being the bureaucracy that causes the most stress. Qualitative analysis of the personal interviews permits a description of ten general problem areas in dealing with bureaucracy to be identified. It becomes apparent, that difficulties arise in the majority of cases if, for example, the use of resources or the division of labour is not planned or the farmers cannot justify their processes. Within the ten tasks perceived as being most stressful, alongside general problem areas there are specific problem areas that generally explain well the volume of bureaucratic stress and burden. A factor analysis enabled this standardised statements about the farmer?s attitude towards bureaucracy to be combined into eight factors. Three of these factors affect the farmer's mental stress with bureaucracy. The factor of "Acceptance of external requests for information and design" reduces the bureaucratic stress felt and the "Lack of time" and "Lack of efficiency of statutory obligations regarding documentation" increase the bureaucratic stress and pressure felt. This dissertation clearly demonstrates which bureaucratic obligations the legislature should change to reduce stress. The procedure selected for this has proved itself. It also demonstrates that farmers should not remain passive when faced with the issue of bureaucracy but should take measures themselves to reduce the burden within their own business. Service providers and advisers are called upon to provide assistance by developing individual strategies. From a scientific point of view, this investigation provides insights into various processes in the organisation of agricultural businesses and the underlying attitude of the farmers themselves.
Pflanzenschutzmittelrückstände im gehöselten Pollen der Honigbiene (Apis mellifera L.) : Auswirkungen einer feldrealistischen Pflanzenschutzmittelmischung auf Stockbienen und den Larvenfuttersaft
(2017) Böhme, Franziska; Zebitz, Claus P. W.
Pesticides are used worldwide and contaminate air, surfaces, soils and the aquifer. Non-target-organisms and non-target-plants may get into contact with pesticides di-rectly via drift or indirectly via run-off, leaching or sowing dust. Due to pollination services and bee products, the honeybee (Apis mellifera L.) is a non-target-organism of major interest for humans. On their flights around the beehive they collect water, pol-len, nectar, honeydew and tree resin. The proteins originating from the pollen are im-portant for nutrition and development of larvae and adults. Pollen is stored and fer-mented inside the hive as beebread and is made of hundreds of pollen loads of differ-ent plants collected over a longer period. Pesticide residue analyses of beebread is a common tool to estimate the contact of honeybees to pesticides in the field. However, such beebread analyses cover a larger time frame and a mixture with uncontaminated pollen will dilute the maximum residue levels of certain plant pollen. Therefore, pesti-cide analysis of bee bread is only an approximate approach to estimate the real pesti-cide exposition. Thus, pollen pellets were collected daily at three distinct sites with differences in agri-cultural intensity in Baden-Württemberg from 2012 - 2016 during the agronomic active season (spring/summer). We wanted to give detailed information on the daily contact to pesticides as well as changing pesticide frequencies and combinations throughout the season. 281 pollen pellet samples, each representing a single day, were analyzed for 282 active ingredients currently used in agricultural practice (publication 1). Huge qualitative and quantitative differences in the pesticide load between the sites were discovered. The meadow site near Göppingen was the least contaminated. In five ob-servation years only 24 different substances were found in 56 % of the samples with concentrations up to 300 µg/kg. The more intensive site in Ertingen is characterized by grains and maize for biogas plants. Only 13 % of the samples were uncontaminated, in the remaining samples 37 substances with maximal concentrations up to 1,500 µg/kg were detected. The site with the highest occurrence of crop protection was close to Heilbronn. Permanent crops such as wine and orchards shape the landscape. The high-est detected concentration was 7,178 µg/kg. All samples were contaminated with up to 58 different substances. During the five years of observation 73 different pesticides were found. Due to admis-sion regulations, there was a high likelihood to find 84 % of these substances in pollen. Twelve substances were found that are either not registered as plant protection prod-ucts or are not supposed to get in contact with bees. This indicates a need for further improvement of seed treatments and increasing awareness of flowering shrubs, field margins and pesticide drift. Concluding from the majority of concentrations and pesti-cides found, we assume no misuse of pesticides by the farmers at our three sites in the observation period, which would lead to direct intoxication. Considering LD50 values, the here detected concentrations are sub-lethal for honeybees. However, at any tested site and in most of the samples a mixture of different pesticides was found. Yet, it is not known, whether there are effects caused by a combination of different pesticides in sub-lethal concentrations when consumed chronically by honeybees. Therefore, we conducted a field experiment with free-flying honeybee colonies (publi-cation 2). Mini-hives containing about 2,500 bees and sister queens were established at the Apicultural State Institute. Queens were confined to an empty frame to receive lar-vae of known age. These bees were intended to feed on pesticides chronically in two crucial life stages. After larvae hatched from the eggs and after adults hatched from the cells they were fed a pollen-honey diet contaminated with a cocktail of twelve dif-ferent active ingredients in field-realistic concentrations. In colonies treated with a pes-ticide mixture, larval weight was higher and acini diameters of the hypopharyngeal glands of nurse bees were smaller than in the untreated control. However, brood termi-nation and adult lifespan did not differ between both groups. Despite feeding a pesti-cide cocktail chronically starting on the first day of larval being, no obvious negative side-effects in worker bees were detected. It raises the question, if nurse bees, which feed on the contaminated pollen-honey diet, produce larval food and feed larvae, serve as a filter system so that larvae would not come into contact with the pesticides. To determine the fate of pesticides originating from the pollen source, we started a queen rearing (publication 3). Frames with 24 h old larvae were hang into queenless free flying mini-hives. At the same time, the colo-nies were fed a pollen-honey diet containing a cocktail of 13 commonly used pesti-cides in high concentrations. The royal jelly (RJ) fed to the larvae by nurse bees was harvested from the queen cells and subjected to a multi-pesticide residue analysis. Sev-en substances were rediscovered in traces (76.5% of all detections were below 1 μg/kg). However, worker larvae older than three days receive a modified jelly, containing pol-len coloring the food yellowish. That is why we were wondering if contaminated pol-len might have a different effect on the food of worker larvae. Queens of free-flying mini hives were caged to receive larvae of known age. The colonies received a pollen-honey diet, contaminated with high concentrations of a pesticide mixture (publication 4, submitted). Worker jelly (WJ) was harvested on four successive days from larval age three to six and subjected to a multi-pesticide residue analysis. Pesticide concentrations increased with larval age and ranged between 2.9 and 871.0 µg/kg for the different substances and age groups. As the increase of substances in the WJ positively corre-lates with the amount of pollen grains counted in the larval food, we were able to show a direct relationship between the administered pollen in the food and the pesticide concentrations. Considering the maximum food uptake rates of a worker larvae, even the highest con-centrations found, would lead solely to sub-lethal amounts. Even for queens, who con-sume RJ not only as larvae but during their whole life would consume only sub-lethal pesticide concentrations. Especially considering the not-field realistic concentrations we chose for our experiments. Probably, the sub-lethal effects found in our first exper-iment are due to the sub-lethal concentrations worker larvae have taken up chronically during their development. Even though we did not detect acute intoxication symptoms and the concentrations in the brood food are sub-lethal, we cannot infer whether there are impairments of fitness or brood success of honeybee colonies in the long term. However, as honeybee colonies are considered as superorganisms, they are able to tol-erate stressors or the loss of individuals. Therefore, the detection of sub-lethal effects on colony-level in the field is difficult. Yet, a vast problem arises with solitary living insects, for example wild bee species, which are more prone to stressors such as pesti-cides. Solitary insects have more restricted flight and collecting areas, get into contact with pesticides in pollen directly as larvae and have almost no buffer capacities.