Browsing by Subject "Milchvieh"

Now showing 1 - 5 of 5
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    An expert system for planning and designing dairy farms in hot climates
    (2008) Samer Mohamed, Mohamed; Jungbluth, Thomas
    Planning and designing dairy farm facilities is a sophisticated work where a multitude of procedures should be carried out which requires time and efforts; moreover, making mistakes is also possible. Therefore, it is necessary to develop computer tools that have the ability to pre-process the data so as to produce value-added information, in order to accelerate analyses and to improve decision-making. Eleven simulation models were developed to plan and design several dairy farm facilities. Subsequently, an electronic spark map (decision tree) was developed for each simulation model, and then the simulation models were integrated into the relevant spark maps. Afterwards, C# language (C Sharp), which is an object-oriented programming language, was used to develop an expert system via the simulation models and the electronic spark maps. The developed expert system is able to plan and design several dairy farm facilities, e.g. housing system (corrals system), shade structure and roof material, concrete base, cooling system, milking parlor, forage storage, and manure handling system. Subsequently, it plans the farmstead layout, and it leads to implement the technologies, equipments, and machines required for performing several farm operations. Furthermore, it studies water and electricity requirements of the planned dairy farm and the available sources on site. Moreover, it calculates the capital investment and the fixed, variable, and total costs. Data of 6 dairy farms were used to carry out the expert system validation and evaluation. The differences between the actual and calculated values were determined and the standard deviations were calculated. The coefficients of variation range between 3% and 7%. The required input data are 358 thereof a multitude will be recommended by the expert system itself; consequently, it computes and displays 372 output data with the ability of saving and retrieving data. Besides, the system?s accuracy had been calculated using the actual and calculated values of the different outputs and it was found 98.6%. However, the system?s syntax includes 22106 lines. It can be concluded that the developed expert system can be used successfully for planning and designing dairy cow farms in hot climates.
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    Genomic methods for rotational crossbreeding in local dairy cattle breeds
    (2022) Stock, Joana; Bennewitz, Jörn
    Local dairy breeds, such as German Angler, usually have small population sizes and thus a reduced genetic gain, compared to high-yielding breeds. Especially since genomic selection is widely used in the latter, the performance gap between local breeds and high-yielding breeds increased further, as it requires large reference populations in order to achieve accurate estimated breeding values. As a result, many farmers switched to high-yielding breeds. On the other hand, to increase the performance of local breeds the introgression of high-yielding breeds was a common strategy in the past, which resulted in high amounts of foreign genetic material in many of them. Much of the original genetic background got lost, however, they do not achieve the same performance level as high-yielding breeds. Local breeds are therefore faced with the risk of two types of extinction, i.e. a numerical extinction due to the small and decreasing numbers of breeding animals, and a genetic extinction due to massive introgression from high-yielding breeds. To promote local dairy breeds, the implementation of a genomic rotational crossbreeding scheme can be a promising strategy. Local breeds can benefit from a genomic rotational crossbreeding scheme with a high-yielding breed due to 1) an enlarged reference population including both the local breed and crossbred animals, and 2) the increased performance level of crossbred animals. On the other hand, crossbreeding is particularly known to improve functional traits by the exploitation of heterosis. Thus, it appears to be an appealling option for high-yielding breeds, as well, as they tend to struggle with fitness related problems. This thesis aimed to develop genomic methods for numerically small local dairy breeds in crossbreeding schemes in order to improve their genetic gain, genetic uniqueness, and their ability to compete with high-yielding breeds. In Chapter 2 a review study conducted a comparison of different genomic models which are suitable for crossbred data. Different additive models (such as the parental model, a model with breed-specific allele effects, and a single step model) and dominance models, which were either line-dependent, line-independent or included imprinting were discussed. It was concluded that the model choice needs to be made based on desired accuracies, computational possibilities, and data availability. In general, dominance models showed to result in higher accuracies compared to additive models. A breed of origin of alleles model approach was introduced in Chapter 3, which assumes different SNP effects for different origins of haplotypes. This model is suitable for the multi-breed genomic prediction of breeding values of numerically small breeds (i.e. German Angler) that have experienced introgression from high-yielding breeds in the past. The breed of origin of alleles model approach tended to be advantageous for Angler over multi-breed and within-breed genomic predictions with GBLUP. Chapter 4 contains a simulation study about the implementation of a rotational crossbreeding scheme including German Angler x German Holstein, while introducing genomic selection in Angler. Different sizes and structures of growing reference populations and selection goals of Angler were examined. The results showed that crossbred animals had a small overall superiority to both Holstein and Angler populations. In addition, a reference population containing both Angler and crossbred animals, in combination with a selection based on the purebred performance of Angler, gave the highest response to selection in the purebred Angler population and in the crossbred population. The difference between selection methods for Angler individuals could only be observed in the long term, as the purebred-crossbred correlations decreased. In Chapter 5 a simulation study on rotational crossbreeding was performed including different Optimum Contribution Selection methods, in order to realize genetic gain while regaining the original genetic background of Angler. Different constraints regarding mean kinships, native kinships, and migrant contributions from Holstein were applied to investigate their effects on Angler, crossbred, and Holstein populations. Constraining the amount of migrant contribution in Angler increased their genetic uniqueness. However, it led to a notable reduction of genetic gain and thus a reduced superiority of the crossbred animals. The slowed rate of genetic gain and thus the large difference of the performance between the parental breeds could not be compensated by heterosis effects. In Chapter 6 the thesis ends with a general discussion about further genomic models for crossbreeding, and the practical relevance of crossbreeding in dairy cattle.
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    Gesamtbetriebliche Analyse von Weidebetrieben und Weidesystemen in der Milchviehhaltung in unterschiedlichen Regionen Süddeutschlands
    (2014) Kiefer, Lukas Robert; Bahrs, Enno
    Grassland use and particularly pasture milk production is considered a highly sustainable milk production method which renders many ecosystem services for society (such as greater biodiversity, maintenance of rural cultural regions, climate protection due to higher carbon storage capacity of grassland, better animal appropriateness by regular grazing) as opposed to permanent indoor housing with its high portion of concentrate feed. Nevertheless, the share of pasture farming in overall milk production falls behind production by increasing permanent indoor housing in Germany. Therefore, it appears appropriate to analyze the necessary business environment for pasture farming with consideration of selected ecosystem services actually provided and to sketch suitable recommendations for consultation of farmers. Against this background, the research project “Business analysis and optimization of pasture-based farms and pasture systems in dairy farming in different regions of South Germany” was designed. The research project evaluated production technology, labor economics, business success, greenhouse gas emissions and specific ecosystem services of more than 80 specialized pasture milk producers through three economic years (2008/09-2010/11) and was dedicated to analysing economic and ecological competitiveness of pasture milk production at specific locations. As a result the most profitable pasture farms of the sample regarding management income and hourly rate can compete with the most profitable farms that practice permanent indoor housing; thus, they demonstrate potential economic strength of pasture farms at suitable locations. Decisive determinants of economically successful pasture management include organic farming (higher milk prices and financial compensation), high amounts of milk from forage, sufficient milk yield of the individual cow (>6,000 kg), and a great portion of pasture grass in the feed as well as high work efficiency via seasonal calving, all-day grazing and short-lawn pasture. High profitability and low greenhouse gas emissions can be achieved simultaneously through high efficiency of production. Some farms can even make “greenhouse gas avoidance gains” when production costs and proportionate emissions decrease at the same time thanks to reduced feed demand per kg milk. There is still a substantial need for research in the field of greenhouse gas balancing, particularly regarding evaluation of the manifold ecosystem services of pasture milk production. Many pasture-based farms are compensated for the above-mentioned services via the 2nd pillar of Common Agricultural Policy, but such services remain unconsidered in greenhouse gas balancing so far. It is for this reason that pasture-based farms with low productivity as well as organic farms perform poorly compared to more intensive farming with high productivity if they are measured by the established formulas of greenhouse gas balancing. Consideration of ecosystem services in the framework of greenhouse gas balancing would be possible via economic allocation of emissions between milk, meat, and subsidies of the 2nd pillar of Common Agricultural Policy, however. Based on our sample, this approach would result in an approximation of the carbon footprints per kg milk produced by extensive and intensive or organic and conventional farms, respectively. Nevertheless, a fundamental antagonism still persists between high production efficiency, which is desirable from the point of view of climate protection on the one hand and ecosystem services attainable by extensive production on the other hand. Like other milk production systems, profitable pasture milk production associated with lowest possible greenhouse gas emissions requires first of all competent training and consultation of farmers, which meets the requirements of the respective production method. Policy could improve the relevant framework conditions. Successful pasture milk producers are margin optimizers whose economic success depends above all on higher producer prices (organic milk, pasture milk), cost minimizing milk production based on pasture as the cheapest feed for many farms as well as funding of the ecosystem services which are desired by society. Farm growth and increases in milk yield are harder to achieve for pasture milk producers because consolidated areas are missing or more concentrate feed would be necessary. According to the results of the investigated sample, stronger support of the unique image of pasture milk (which does not necessarily mean monetary funding in this context) as well as increased know-how in the field of pasture milk production is desirable in order to establish or develop the numerous very positive approaches of pasture use in grassland regions that were analyzed in our investigation. The latest EU agrarian reform as well as new EAFRD regulations offer some good starting points in this regard.
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    Gesamtbetriebliche Nachhaltigkeitsanalyse von Grünlandsystemen in der Milchviehhaltung in benachteiligten Regionen Südwestdeutschlands
    (2020) Dentler, Juliane; Elsäßer, Martin
    Agriculture is facing major global and regional challenges. The reduction of greenhouse gas and ammonia emissions, the lowering of nutrient discharges, serious losses of biodiversity and food security require urgent action, to determine sustainable structures for the production of agricultural products in general and animal products in particular and to develop solution strategies for the efficient use of resources. A central element of sustainable development is the equal consideration of the three pillars of sustainability - ecology, economy and social aspects. Against this background, the research project A sustainability comparison of grassland-based feeding systems for milk production in disadvantaged regions of south-west Germany was conceived. The aim of the research study was a system comparison at farm level, which not only shows the ecological potential but also the economic and social factors involved in order to improve the understanding of the sustainability of agricultural farm systems and thus contribute to an optimised use of regional resources. For this purpose, grassland-based, concentrate feed-reduced systems of milk production in disadvantaged regions and successful milk systems of year-round barn management with high individual animal performance in favoured areas of southwest Germany were compared. In addition, the potential of using the regional dual-purpose breed Vorderwald for grassland-based, concentrate feed-reduced milk systems was examined. In the present study, the economically most successful farms of the grassland-based sample displayed a high economic efficiency in the calculated management income compared to conventional dairy farms. Nevertheless, it became clear, that economically sustainable milk production is not given at all locations. In principle, organic dairy farms in grassland regions can profit economically from high prices for organic milk together with subsidies from agri-environmental measures combined with a high use of pasture grass and low external costs (concentrated feed, external labour). This was also evident with regard to the social parameters, especially in the areas of stress, leisure time and appreciation by the population and by colleagues, a high degree of social sustainability was demonstrated. With regard to the efficiency parameters, the farms of the grassland-based sample performed significantly better than the intensive dairy farms, especially with regard to the net food conversion efficiency, with an average of 295 % related to gross energy, and the nutrient efficiency, with a 10 % higher use efficiency of nitrogen and a 55 % higher use efficiency of phosphorus. The latter were characterised by an average nitrogen surplus of 150 kg per ha. By taking into account the CO2-storage in conjunction with the integration of ecosystem services in the allocation of emissions, it was also possible to demonstrate a lower carbon footprint for grassland-based milk production in disadvantaged regions of southwest Germany. Furthermore, it could be shown that the same feeding system cannot be applied equally beneficially for all breeds and that Vorderwald cattle are better adapted to a system with full pasture, low concentrated feed input and seasonal calving compared to Holstein cattle. Complex agricultural processes ultimately mean that, depending on production methods and consumption, almost identical products have very different effects on the environment, climate, income, social aspects and health. The present study shows that milk production with a high proportion of permanent grassland, adapted animal genetics and a very low dependence on external production factors such as energy- and protein-rich fodder as well as chemical synthetic fertilizers and pesticides, has significant advantages over milk production in intensive systems and can be regarded as eco-nomically, ecologically and socially sustainable. A consistent implementation of this strategy towards systems in which smaller, more robust animals of a dual-purpose breed produce milk and meat almost exclusively on the basis of their natural feed base with a high efficiency per hectare could therefore indicate a direction towards more sustainable milk production, livestock farming and agriculture in general. In this context, organic farming is seen as particularly resource-saving and environmentally compatible and is discussed as a concept to improve sustainability in agriculture. For sustainable development and defusing conflicts of objectives, however, an overall perspective must be adopted; looking at individual aspects of production is not sufficient. In addition to adjustments in agriculture, far-reaching changes in consumer behaviour and food waste are necessary. This will require considerable political will and cooperation at farm and society level
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    Langfristige Beurteilung der Energieversorgung von Milchkühen bei unterschiedlichem Kraftfuttereinsatz
    (2020) Gerster, Elisabeth Katharina; Rodehutscord, Markus
    The first objective of the present study was to compile the current knowledge concerning the effect of the amount of CON on dry matter (DM) intake and milk yield of dairy cows, by regression analysis. For this purpose, a dataset was compiled containing 46 studies with feeding trials and graded inclusion levels of CON. When offering the roughage ad libitum, a quadratic relation was found between CON intake and roughage intake. Taking into account the substitution of roughage, the observed increase of milk yield was less than expected. The second objective was to verify the response of Simmental dairy cows to a long-term reduction of the CON input, in terms of dry matter intake, milk yield, and energy supply. During a feeding trial conducted over a two-year period at the experimental station LAZBW in Aulendorf (cooperative research project „optiKuh“) each 24 Simmental dairy cow was fed either 250 (group 250) or 150 (group 150) g CON per kg energy-corrected milk yield (ECM) throughout lactation. Grass and maize silage as well as straw and hay were combined in the total mixed rations to ensure an energy concentration of 6.6 MJ NEL per kg DM of the roughage in both groups throughout lactation. The CON contained a mixture produced on-site (winter wheat, winter barley, faba bean) and rapeseed meal. At 165 days in milk, each cow in both groups was switched individually to a ration containing less CON. Data were gathered also during the dry period. Feed was offered for ad libitum consumption. Statistical analyses were done separately for the lactation and dry period. As fixed effects the calendar week, the group, the parity, and the interaction group*parity entered the model, respectively. Additionally, the days in milk were included as a covariate during lactation. During lactation the mean daily DM intake did not differ significantly between group 250 (21.6 kg DM) and group 150 (21.0 kg DM). The calculated substitution of roughage amounted to 0.75 kg DM per kg CON DM during the mentioned trial period. As lactation progressed, more roughage was substituted. The group 250 had a higher milk yield during the first half of lactation, but a lower milk yield during the second half. The mean milk yield was equal in both groups (28.7 kg ECM per day). The examined blood characteristics (8, 28, 100 days p. p., at drying off, 14 days a. p.) and the milk fatty acids analysis by gas chromatography (5, 28, 100, 200 days p. p.) reflected the different progressions of the energy balance of the two groups. On average the group 250 reached a positive energy balance already at 37 days in milk. Probably owing to a better glucose supply after calving, the serum insulin concentration increased faster and supported the replenishing of body reserves at the expense of milk yield. On the contrary, the group 150 achieved a positive energy balance only after 72 days in milk on average. Indicating the mobilization of body reserves, the blood of group 150 showed a significantly higher D-ß-hydroxybutyrate concentration, and the milk fat a significantly higher concentration of long-chain fatty acids 28 days p.p.. However, the values were within the physiological range. The reduction of CON did not increase the likelihood of illness. During the dry period, despite equal feeding of both groups in this period, the group 150 had an increased DM intake of 0.9 kg DM per day (p=0,026). Thus, they restored body energy reserves. Over time both groups succeeded in balancing the energy deficit of the beginning of lactation. The proposal of SUSENBETH (2018) for the calculation of the energy requirement of dairy cows improved the plausibility of the calculated energy balances compared with the factors according to GfE (2001). The third objective was to develop a model for the estimation of energy balance in the first third of lactation based on characteristics of production with focus on concentration of milk fatty acids. For this purpose, the milk fatty acids analyses 5, 28 and 100 days p. p. of the feeding trial were used (n=200). The model was derived from the regularized linear regression method „elastic net“. The variables milk yield on sampling day, milk fat content, concentrations of the milk fatty acid C12:0 and the milk fatty acid C18:0, as well as the relations n-6/n-3, C15/C17 and oleic acid/C15 were selected. An estimation error of 13.1 MJ NEL per day was determined by leave-one-out cross-validation. Potentially, the model seems to be applicable for the detection of a severe negative energy balance at the beginning of lactation. But first a validation with an independent dataset is required.