Modifying milk fat composition to enhance its content of valuable fatty acids (FA) is required to meet the needs of a society which is becoming better informed about the relationship between diet and health. Manipulating the cow’s diet is an effective, natural way to modify the amount and composition of milk fat of cows. The two main factors that affect the cow’s diet concern management system (MS; pasture vs. confinement), and supplementation of diets with lipid supplements. Marine oils specifically are fed to enhance milk with n-3 long-chain polyunsaturated FA (n-3 LC-PUFA). The effects of source of marine lipid supplement (LS; fish oil vs. microalgae) in the cow’s diet and its interaction with MS on milk fat composition have not been studied. Thus, the main objective was to determine the interaction of MS and LS on milk FA profile and on expression of lipogenic genes in mammary, adipose and liver of lactating dairy cows. Compared with cows in confinement, grazing cows produced milk fat with lower content of unfavorable FA (12:0-16:0), while increasing the levels of beneficial FA including cis-9 18:1, 18:3 n-3 and conjugated 18:2. Feeding either fish oil or microalgae improved levels of n-3 LC-PUFA and reduced those of 16:0 in milk fat regardless of MS, but concurrently increased the level of other trans 18:1 isomers at the expense of trans-11 18:1. The reduced secretion of 12:0-16:0 in milk from grazing compared with confined cows was associated with lower mammary expression of lipogenic genes suggesting that part of the effect of MS on milk FA profile is mediated transcriptionally. The effect of LS on lipogenic gene expression was tissue specific with the greatest response to treatment observed in liver despite its minor role in lipogenesis in cattle relative to the mammary and adipose. Major conclusions were that milk produced in pasture systems has a more healthful FA profile than that of confinement systems, and that MS and LS have tissue specific effects on lipogenic gene expression in dairy cattle which have important effects on cow performance and healthfulness of the milk FA profile.

Backgounding beef cattle is an inherently risky venture. Producers faceproduction risks as well as marketing risks. If a backgrounding operation is to be viable,these risks should be addressed and effectively managed. While some effective riskmanagement tools are currently available to livestock producers, some other potentiallyuseful risk management tools, for various reasons, have been previously unavailable.Two such tools which could help livestock producers achieve the overall goal ofmanaging net income risk are a program for managing feed ingredient nutrient and pricevariability in the selection of minimum cost feed rations and government subsidizedlivestock price insurance.Due to lack of data and limited computational power of solvers, risk has seldombeen introduced into the feed ration selection process. Presently, both feed ingredientnutritional data and appropriate solvers are available, allowing for risk to be fullyconsidered in this decision-making process. Only recently has there been policy effortsto establish subsidized price or revenue insurance for livestock producers. Theintroduction of such insurance to livestock producers offers potential risk managementbenefit but also has the potential to introduce improper incentives to livestock producers.This study will evaluate both of the aforementioned livestock risk managementtools. In addition to evaluating their effectiveness, the policy concerns of subsidizedlivestock insurance will also be addressed. Results will be relevant to a broad range ofentities. In addition to livestock producers wishing to manage the risks associated withtheir operations, agribusinesses that provide service to these producers such as feed salesor financial lending will benefit from knowing how these risk management strategiesperform. Furthermore, policy makers who will structure livestock insurance products canhopefully do so more efficiently based on the results of the livestock insurance analysis.

The relationship between quantity traded and transaction costs has been one of the main focuses among financial scholars and practitioners. The purpose of this thesis is to investigate the informational relationship between these variables. Following insights and results of Milgrom (1981), Feldman (2004), and Feldman and Winer (2004), we use New York Stock Exchange (NYSE) data and kernel estimation methods to construct the distribution of one variable conditional on the other. We then study the information in these conditional distributions: the extent to which they are ordered by first order stochastic dominance (FOSD) and by monotone likelihood ratio property (MLRP). We find that transaction size and effective spread are statistically significantly orrelated. FOSD, a necessary condition for a "separating signaling equilibrium", holds under certain conditions. We start from two-subsample case. We choose a cut-off point in transaction size and categorize the observations with transaction sizes smaller than the cut-off point into group "low". The remaining data is classified as "high". We repeat this procedure for all possible transaction size cut-off points. It turns out that FOSD holds nowhere. However, once we eliminate transactions at the quote midpoint, the "crossings" between exchange members not specialists, FOSD holds for all the cut-off points fewer than 15800 shares. MLRP, a necessary and sufficient condition for the separating equilibrium to hold point by point of the conditional density functions, does not hold but might not be ruled out considering the error in the estimates. We also find that large trades are not necessarily associated with large spread. Instead, it is more likely that larger trades are transacted at the quote midpoint (again, the non-specialist "crossings") than smaller trades. Our results confirm the findings of Barclay and Warner (1993) regarding the informativeness of medium-size transactions: we identify informational relationships between mid-size transactions and spreads but not for trades at the quote midpoint and large-size transactions. That is, we identify two regimes, an informational one and a non-informational/liquidity one.

Made available in DSpace on 2015-04-17T14:49:18Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 787297 bytes, checksum: ef844b907c7df9d6b79a546d0a5cdc3b (MD5) Previous issue date: 2009-09-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The carciniculture is an important economic activity for Brazil, basically in the farming of a specific shrimp species (Litopenaeus vannamei). This species has shown in the last years an unsatisfactory performance due to problems caused by illnesses. That has been increasing the interest for the farming of native species like the Farfantepenaeus subtilis which has a better resistance to illnesses, besides being tolerant to several salinity variations they also have an availability of adult females and post larvae and a facility for reproduction in confined places. The nutrition of this species has to be better studied, like the necessities of vitamins A, E and C in these animals s diets. As well as knowing the stability of these vitamins in the processing, storage and handling of this diet. This study consisted of a formulation of eight diets with different levels of vitamins A, E and C and a control diet (with no vitamins). The vitamins were quantified right after the storage period (60 days) to evaluate the losses. The shrimps of the Farfantepenaeus subtilis species were fed with these diets for thirty days, in which it was evaluated the biomass gain and the survival rate. The major vitamin losses were of retinol, α-tocopherol, and ascorbic acid, respectively. The major survival rates (100%) were observed in the R1 and R4 diets which received different levels of vitamin E (184 e 364 UI/Kg), respectively. / A carcinicultura é uma atividade economicamente importante para o Brasil, sendo baseada praticamente no cultivo de uma espécie de camarão (Litopenaeus vannamei). Esta espécie nos últimos anos tem mostrado desempenho insatisfatório devido aos problemas causados por enfermidades. Isso vem despertando o interesse pelo cultivo de espécies nativas como o Farfantepenaeus subtilis que possui uma resistência maior as enfermidades, além de ser tolerante a amplas variações de salinidade, tem disponibilidade de fêmeas maduras e póslarvas e a facilidade de reprodução em ambientes confinados. A nutrição da espécie Farfantepenaeus subtilis precisa ser melhor estudada, como as necessidades de vitaminas A, E e C nas dietas destes animais. Assim como conhecer a estabilidade destas vitaminas frente ao processamento da dieta e ao armazenamento e manejo. O estudo consistiu na formulação de oito dietas com diferentes níveis de vitaminas A, E e C e uma dieta controle (sem vitaminas). As vitaminas foram quantificadas logo após o processamento das dietas e após período de armazenagem (60 dias) para avaliar as perdas. Os camarões da espécie Farfantepenaeus subtilis foram alimentados com estas dietas durante trinta dias, onde foram avaliados o ganho de biomassa e a taxa de sobrevivência. As maiores perdas vitamínicas foram de retinol, α-tocoferol e ácido ascórbico, respectivamente. As maiores taxas de sobrevivência (100%) foram observadas no tratamento R1 e R4 que receberam diferentes níveis de vitamina E (184 e 364 UI/Kg) respectivamente.

This thesis deals with the activity of a thyroid gland of a goat in terms of an excessive iodine excretion in urine and milk. The milk iodine content as a potential source of iodine for humans is still a significant affair. Five milk collections were done in five observed farms during a lactation period. It was collected 144 individual mixed milk samples from 32 animals in total. Urine collections were made five times in the five observed farms 29 individual urine samples in total from 12 animals. The total iodine excretion in milk and urine was set. The average iodine content in milk of individual farms ranged from 41.72 to 143.54 ?g I.l-1 and the average iodine content in urine of individual farms ranged from 104,1 to 165,3 ?g I.l-1. It appears from that that type of stabling and also ration with mineral supplements have an impact on the iodine content. No impact on the iodine content was registered from lactation stage, age or specific breed. There's possible dependency on iodine content in milk and iodine content in urine.

In the ZD Kojčice cooperative farm, a stable in Krasíkovice was studied in 2013 and 2014. The farm's production technology and the quality of the ensiled feed, feeding techniques, composition of the feed portions and selected milk production indicators were examined. The economy of milk production was also assessed. The production of ensilage ensured quality feed that was the basis for the milk cows' feed portions. The results show that the feed portions were well balanced in comparison to the recommended nutritional values for milk cows. The average yield in 2014, unlike 2013, decreased by 146 l to 5 960 l per milk cow per year. The costs per feed day were established at 138,2 Kč. The average costs for one liter of milk were 8,75 Kč/l.

Thesis on quality impact and processing silage and silage on milk yield of dairy cows discusses the theoretical part, mainly on the composition of the diet and milk production. In addressing this issue is important to ensure animal welfare. An integral part of the milk production is respecting technological procedures harvesting and preservation of harvested crops. Silage quality and composition of the diet affect the proper function of the rumen, which has an impact on the quality and composition of milk. The quality of milk and its composition affects the purchase price of milk. The practical part deals with methodology and data processing of milk production, the composition of the ration and analysis of silage and their subsequent statistical processing. Further consideration was given to the possible influence of the season. Statistical results were then compared with many experts. The results fell the most in 2015, which increased the average monthly milk yield . In this year , the best fed silage and forage

The diploma thesis analyses the level of nutrition of dairy cattle of a particular company and looks at factors that influences milk production. Under the operating conditions of this particular company is evaluated: the quality of bulk feed, the composition of feed diet in terms of required amounts of nutrients and energy for production levels and compared the recommended values.The thesis assesses feeding technique, housing technology and hygiene of obtaining milk. The production and health of dairy cattle breeding over the course of one year is depicted. The work also focuses on evaluating the basic economic indicators of milk production.

Topics thesis focuses on the feed mixing wagons, specifically on the impact of individual components of mixed feed rations with feed mixer wagons without pickup cutters accuracy loads. The result of this work is your own assessment of the qualitative characteristics of individual components of mixed feed rations, but their influence on the possible inaccuracy of the weighing equipment of these vehicles and thus on the actual composition of the diet and the resulting measures to prevent the occurrence of these inaccuracies when preparing feed.

The thesis deals with the analysis of the phase feeding in herds of Holstein cattle in specific operating conditions and its relation to milk yield and health of dairy cows. In the reference event to be optimized ration drystanding cows and lactating cows in comparison protocols laboratory analysis of mixed rations to standard NRC by the enterprise uses for compiling rations. The thesis was evaluated the effect of ration on milk yield and content of milk components and also affect the incidence of metabolic disorders. The aim of the thesis was to analyze the phase nutrition of dairy cows in the reporting company in relation to milk production and health, to evaluace the quality of feed rations, some feed and feeding technique. It was found that the monitored parameters do not match any breed mixed rations used in the standard, which could lead to reduced levels of production and reproduction and deterioration in health of dairy cows. It was further found that in the observed rearing occur very frequent occurrence of metabolic disturbances and fluctuations in the milk production.