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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Kvalita objemných krmiv ve vztahu k ekonomice výroby mléka / Quality roughage feed in relation to the economy of milk production

NÁVARA, Drahoslav January 2012 (has links)
The aim of this thesis was to evaluate in selected levels of nutrition and feeding of dairy cows in relation to the economy of milk production and suggest possible options for improving the profitability of milk production. They have been selected four firms, two keeping Holstein cattle and two with red coloured cattle. One company was with highest production and the second company was with average production. The aim was to assess the profitability of milk production at peak and average enterprises, especially given the quality of forage and the cost of ration. The selected companies we evaluated the composition of feed rations, especially forage quality indicators. For assessment of milk production of dairy cows were selected for the second group, or third lactation calved in the same period, and after ten pieces from each company. We also evaluated the cost of feeding dairy cows in milk and in particular the cost to produce one liter of milk a day and feed at the cost of production for the entire lactation. Selected breeds we all observed points compared with each other.
2

Optimal feeding systems for small scale dairy herds in the North-West Province of South Africa

Manzana, Nonzwakazi Patience 11 April 2008 (has links)
The North West Province (NWP) identified dairy farming as a priority as it has the potential, not only for job creation, but also as a sustainable source of high quality protein for rural communities. With the correct type of management systems, small-scale dairy farms have the potential to be economically feasible. For the purposes of this study, a small-scale dairy farm was defined as a farm which produced less than 500 litres of milk a day irrespective of the number of cows or size of the farm. The study area was Central North West Province and the study was a longitudinal observational study conducted with 15 small-scale dairy farmers from 2002-2006. Nutrition was found to be a major constraint to the production capacity of dairy cows studied. It was found that farmers were deficient in the knowledge, skills and experience required to develop an affordable and balanced feeding system based on locally available ingredients. Dairy rations were given to prevent malnutrition or starvation, rather than to increase production. It was also shown that feeding of the cattle on the farms investigated, was influenced more by availability and affordability of locally obtained feed ingredients than by planning nutrition to increase milk production. Available statistics show that there are approximately 257 000 dairy cattle in NWP, with the greatest numbers in the Central Region (175 235) and smaller numbers in the Western (59 852) and Eastern (21 873) Regions. These cattle produced approximately 230.4 million litres of milk annually (12.5% of national production) with an estimated value of R304.1 million at R1.32/l, excluding value-added products in the form of cheese, yoghurt, milk powder, and others in 2002. The method used was a longitudinal study conducted from 2002 to 2006 in three phases. In the first phase, situational analysis using participatory rural appraisal (PRA) and observation was used to outline the extent of the constraints and start to design appropriate interventions. Feeds used by the farmers for feeding dairy cows – both supplements and roughage - were tested and evaluated. In the second phase, three different feeding systems were designed from the data obtained from PRA, in consultation with small-scale dairy farmers, established commercial dairy farmers, state veterinary and agriculture staff, feed manufacturers and distributors and the commodity organization (MPO) to optimize the nutrition of the dairy cows. The third phase was field testing of interventions and observations of the implementation by farmers. It was found during the PRA phase that the majority (n=9) of farmers had been in dairy farming for not more than five years, five farmers had six to ten years in dairy farming and only one farmer had 11 to 15 years in dairy farming. Dairy farming is a very highly skilled operation and farmers need to have experience and knowledge to succeed. Five years is insufficient. Therefore capacity building and training were instituted over the period 2002 to 2005. Also, 60% (n=9) of the farmers were not affiliated to any agricultural organisation, so membership of the Milk Producers Organisation was facilitated for all farmers in the study. It was also found that the cattle were not identified and neither production nor financial records were kept. Testing and evaluation of feed used showed that it was of poor quality, deficient in protein, energy and minerals and no effort was made to balance the ration. In the second phase, three feeding systems were developed form data obtained and observations during phase one. These were A: a semi-intensive farm based ration using available crops, pastures and crop residues with minimal rations purchased; B: an intensive, zero-grazing dairy system using a total mixed ration (TMR) for farmers with smallholdings of less than 5 hectares per cow and C: Traditional, extensive or dual purpose system where the calf drank from the cow until weaning and milking was done only once a day, for farmers with more than 5 ha grazing available per cow. The last was a low-input/low output system and was implemented by a majority (n=8) of the farmers. System B was chosen by two farmers and not adopted by any of the two farmers in the long run. System A was adopted by three farmers. Four farmers left dairy farming for various reasons during the study. By July 2006, the farmers had changed to commercially formulated rations or licks and the body condition score of the cows had improved. Milk production per cow did not increase, but this may have been due to the increased price of meat and the fact that a majority of the farmers were using a dual purpose system and selling calves at weaning for a very good price. It was concluded that extension officers should get extra training in dairy if there are dairy farmers in their areas as this is a very specialist type of extension. They should also work closely with veterinary services including veterinarians, animal health technicians and the health inspectors. Further research should be done to optimise the traditional model as this is relatively profitable, has a lower risk and is less labour intensive. It is probably a good way to increase food security, particularly in families when only one or two members have an income from a pension or part-time employment. The prices realised from informal sales of milk and calves can give a stable income. The “community farms” should be economically evaluated in terms of each beneficiary being able to get a “living wage” out of the projected profits of the farm. The MPO and other stakeholders should give very specific training to new dairy farmers, based on the models that were used in this study. It is essential that framers be taught to “look forward” and get a pro-active attitude. They must also understand that quality, balanced rations are the key to success – poor rations are expensive rations, because they result in unhealthy cows and poor production. Finally, ongoing and effective monitoring and evaluation of extension is an effective instrument for project sustainability – farmers must be involved and participate in their own evaluation - extension is not all about paper work it is about measuring performance and good service delivery. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2007. / Paraclinical Sciences / unrestricted
3

Stanovení kaseinových frakcí v kravském mléce / Determination of caseins in cow milk

Gejdošová, Lucie January 2008 (has links)
The diploma thesis is dealing with design of analytical method for determination of caseins in cow‘s milk. Capillary electrophoresis was used as separative method. The developed procedure was verified on real samples. Theoretical part gives basic information about caseins. Their chemical and physical properties, structure, way of manufacturing, usage in food industry and non-food applications are described. There are further some nutritional factors mentioned, whose application in cattle nutrition can affect milk composition, especially milk protein concentration. Literary part contains summary of capillary electrophoresis methods used for casein determination. Experimental part describes used separative system, procedure of casein isolation from milk and casein content in individual milk samples. Separation of milk caseins was performed in an untreated fused-silica capillary with dimensions of 50 um i.d. x 96 cm total length (71 cm effective length). Phosphate buffer (10 mM, pH 2,5) served as the background electrolyte. Casein from milk was obtained by isoelectric precipitation at pH 4,6 after adding 10% acetic acid. Product was washed with acetone to remove fat and dried. Total casein yield was the highest in bio-milk (27,04 g/l), the lowest in skim long-life milk (22,04 g/l). The diploma thesis has arisen on the basis of cooperation of Institute of Food Science and Biotechnology, Faculty of Chemistry, Brno University of Technology and Research Institute for Cattle Breeding, Ltd., Department of Animal Nutrition Physiology in Pohořelice.
4

Stanovení kaseinů kapilární elektroforézou / Determination of caseins by capillary electrophoresis

Mičíková, Ivana January 2009 (has links)
The diploma thesis, Determination of the caseins by the capillary electrophoresis, is dealing with a creating of the analytical method for a determination of the caseins in cow‘s milk. The capillary electrophoresis was used as a separative method. The developed procedure was optimalized and verified on standards of the caseins and the real samples. The theoretical part gives an information about the compound of cow's milk, caseins, their usage in the food industry and the non-food technologies. There are mentioned some further nutritional factors, whose application in the cattle nutrition can affect the milk composition. The experimental part describes the procedure of the caseins isolation from milk, the used separative system and the determination of the caseins in the lyophilisated samples of milk. The separation was performed in two untreated fused-silica capillaries. Both of them had the same internal diameter: 50 m. The total length of the first capillary was 96 cm (71 cm of effective length) and of the second used capillary 125 cm (effective length 100 cm) The phosphate buffer (10 mM, pH 2,5) served as a basic electrolyte. The diploma thesis has arisen on the basis of the cooperation of the Institute of Food Science and Biotechnology, the Faculty of Chemistry, Brno University of Technology and the Research Institute for Cattle Breeding, Ltd., Department of Animal Nutrition Physiology in Pohořelice.
5

Analýza kaseinů kravského mléka kapilární elektroforézou / Analysis of cow milk caseins by capillary electrophoresis

Dvořáková, Irena January 2010 (has links)
The diploma thesis is dealing with the determination of caseins in lyophilised samples of milk using the method of capillary electrophoresis (CE). This method was optimised and verified by Ivana Micikova in her diploma thesis in 2009. The theoretical part of the diploma thesis gives information about the chemical compound of cow's milk. Caseins and their usage in the food and non-food industries are described in a separate unit. Impact of both the nutritional and non-nutritional factors on the composition of the milk is discussed further. The description and the principles of the CE and a list of the methods of CE used in the last several years are stated at the end of this part. The experimental part is focused on the preparation of the solutions, process of casein isolation and its analysis. It summarises the setting of the experiment, sampling and sample processing and the composition of the feeding mixtures. The diploma thesis has arisen on the basis of the cooperation of the Institute of Food Science and Biotechnology, the Faculty of Chemistry, Brno University of Technology and the Research Institute for Cattle Breeding, Ltd., Department of Animal Nutrition Physiology in Pohorelice.

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