Eksperimentas buvo atliktas su 90 mišrūnių kiaulių, suskirstytų į bandomąsias grupes, atsižvelgiant į jų kilmę, lytį ir pradinį kūno svorį. Kiaulės buvo suskirstytos į šešias bandomąsias grupes (15 gyvūnų kiekvienoje grupėje): 1 grupė - gyvūnai šeriami visaverčiais pašarais ir laikomi ganykloje, 2 grupės - gyvūnai šeriami visaverčiais pašarais ir laikomi tvarte, garduose su kraiko pakratais, 3 grupė - gyvūnai šeriami visaverčiais pašarais ir laikomi tvarte, garduose be kraiko pakratų, 4 grupė - gyvuliai šeriami visaverčiais pašarais ir liucernos pašarais, laikomi lauke, grupė 5 - gyvuliai šeriami visaverčiais pašarais ir liucernos pašarais, laikomi tvarte, garduose su kraiko pakratais, 6 grupė - gyvuliai šeriami visaverčiais pašarais ir liucernos pašarais, laikomi tvarte, garduose be kraiko. Tyrimo objektas: penimų kiaulių elgsena atsižvelgiant į šėrimą ir laikymo būdus (tvarte ar vasaros stovyklose) Trimo tikslas: nustatyti laikymo sistemų (tvarte ar vasaros stovyklose) ir šėrimo (pilnavertis pašaras ir/arba papildytas liucernos pašaru) poveikį skirtingais amžiaus laikotarpiais penimų kiaulių elgsenai. Išvados. Analizuojant skirtingus penėjimo laikotarpius, nustatyti kiaulių elgsenos ypatumai ir ryšys su produktyvumu. Pirmoje ir antroje penėjimo fazėje (apie 50 kg ir 100 kg) nustatyti įtakojantys veiksniai produktyvumą susiję su poilsio periodų, judėjimo aktyvumų. Kiaulės augintos be kraiko, daugiau laiko skirdavo poilsiui, buvo mažiau aktyvios, ir agresyvesnės... [toliau žr. visą tekstą] / The experiment was performed on a total of 90 hybrid pigs divided into experimental groups based on their origin (litter), sex and initial body weight. The pigs were assigned to six experimental groups (15 animals per group): group 1 – animals fed a complete diet and kept freerange, group 2 – animals fed a complete diet and kept indoors in pens with litter bedding, group 3 - animals fed a complete diet and kept indoors in pens without litter bedding, group 4 – animals fed a complete diet and alfalfa forage, kept free-range, group 5 - animals fed a complete diet and alfalfa forage, kept indoors in pens with litter bedding, group 6 - animals fed a complete diet and alfalfa forage, kept indoors in pens without litter bedding. All management systems were animal welfare-friendly. Both at the first and second stage of fattening (approx. 50 kg and 100 kg BW, respectively), the experimental factors had a significant effect on the majority of behavior patterns in pigs. An increase in rest periods and a reduction in locomotor activity and other types of behavior were observed in older animals.

Hos grisar finner man flera stereotypiska beteenden, som rörbitning och svansbitning. Dessa beteenden är relativt vanliga hos grisar. En miljöberikning definieras som förbättring av ett djurs välfärd, både psykologisk och fysiologiskt, genom förändringar hos djurets omgivning. Denna studie har undersökt om miljöberikningar kan minska stereotypiska beteenden hos grisar. De två olika miljöberikningar som har använts är en jutesäck fylld med halm och en Jolly Ball™. De tre stereotypiska beteendena som studerades var rörbitning, svansbitning och bukmassage. Studien utfördes på 107st grisar uppdelade på 12 boxar, under totalt tre veckor. Alla tre stereotypiska beteenden minskade statistiskt signifikant . Detta visar att båda miljöberikningarna hade en positiv effekt på grisarna då de minskade deras stereotypiska beteenden. De interagerade mer med jutesäcken fylld med halm än vad det gjorde med Jolly Ball™.  Grisarna föredrog den miljöberikningen som var omformbar, förstörbar, ätbar, tuggbar, vilket går i linje med liknande studier. / Among fattening pigs you find several stereotypical behaviours, such as bar-biting and tail-biting. These behaviours are quite common among domestic pigs. Environmental enrichments are often used to reduce stereotypical behaviours in animals.  An environmental enrichment is defined as an improvement of an animal’s welfare, both psychologically and physiologically, through changes in the environment of the animal. With this study, different environmental enrichments were studied to see if they can reduce stereotypical behaviour among fattening pigs. The two different environmental enrichments used were a jute sack filled with straw and a Jolly Ball™. The stereotypical behaviours that were looked at were bar-biting, tail-biting and belly-nosing. The study was carried out on 107 pigs divided into 12 pig boxes, during 3 weeks in total. All three stereotypical behaviours decreased significantly. This shows that the environmental enrichments had a positive effect on the pigs, since they reduced their stereotypical behaviour. The pigs interacted more with the jute sack than they did with the Jolly Ball™.  The pigs preferred the environmental enrichment that was destructible, edible, deformable and chewable, which fits well into similar studies that have been executed.

The diploma thesis deals with the nutrition fattening cattle. The evaluation of the feed rations was based on the needs of nutrients for the recommended values in relation to utility parameters on the given farm. The work also evaluated feeding and stabling technique, the quality of feed composition and feed rations and evaluation of the basic economic indicators of fattening bulls.

SANTOS, Carlos Henrique dos Anjos dos. Engorda de juvenis recentes da lagosta espinhosa panulirus laevicauda (latreille, 1817) alimentados com ração comercial para camarão marinho e os moluscos mytella falcata e perna perna, em condições de laboratório. 2006. 92 f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrária, Departamento de Engenharia de Pesca, Fortaleza-CE, 2006 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-12T12:05:16Z No. of bitstreams: 1 2006_dis_chasantos.pdf: 6291153 bytes, checksum: 8e3cf4774f001785390ffded2d0ea61f (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-07-12T12:05:37Z (GMT) No. of bitstreams: 1 2006_dis_chasantos.pdf: 6291153 bytes, checksum: 8e3cf4774f001785390ffded2d0ea61f (MD5) / Made available in DSpace on 2016-07-12T12:05:37Z (GMT). No. of bitstreams: 1 2006_dis_chasantos.pdf: 6291153 bytes, checksum: 8e3cf4774f001785390ffded2d0ea61f (MD5) Previous issue date: 2006 / The spiny lobster represents an important economic fisheries resource in Ceara State, contributing to the generation of profitable activity and employment. Due to the exploitative and destructive fishing practices, along with the degradation of the natural habitat from pollution and human activity, a precipitous decline in the wild populations has occurred. This activity had begun by 1950s. Since then, different types of vessel and gears were used to catches of this resource. However, with the catches of this crustacean and the growing market demand, as a consequence, decrease natural stock. At present, this activity have had a strong decrease and one of the few ways to expand production is through aquaculture or culture of these species in captivity. In view of this decline, the objective of the present study is to analyze the development of early juvenile spiny lobster Panulirus laevicauda fed on molluscs Perna perna, Mytella falcata and commercial marine shrimp ration + Artemia sp. biomass, in laboratory condition. This experiment was carried out in the Aquaculture Technology Center, Federal University of Ceara in a 122 days feeding trial. The juveniles were submitted to three treatment (treatment A – P. perna, treatment B – M. falcata and treatment C – commercial ration + Artemia sp. biomass) repeated 4 times. Initial density used was one individual per container. The feed rate was 10 % of the individual biomass. During the experiment bromatological analyses of the feed was done, verifying protein, lipids, ash, carbohydrate and humidity. The chemical and physical parameters of the experimental water (pH, temperature and salinity), were measured daily and the juveniles were measured verifying cephalotorax and total length and weighed at each 30 days of culture. At the end of the experiment, chemical and physical parameters, biometric data, number and frequency of molts per individual, survival rate were analyzed for the determination of statistical tests. Analysis with Kolmogorov-Smirnov the Student Test (chemical and physical parameters), Analysis of Variance (ANOVA) and if necessary the Tukey Test (biometric data, number and frequency of molts and intermoult per individual) and test Qui-Quadrado of Pearson (survival rate), respectively. For the statistical tests, it has been used µ = 0,05 significance level. In this work chemical and physical parameters showed minimum, maximum and medium value much close among the treatments. Analysis with Kolmogorov-Smirnov showed that pH, temperature and salinity, attended normal supposition. These parameters showed no significant differences (P > 0,05) with the Student Test during the cultures among the treatments. After finished the experiment, chemical and physical parameters, biometric data, number and frequency of molts per individual, survival rate were analyzed for the determination of statistical tests. The results of gross weight (g) and cephalotorax (mm) and total (mm) length of spiny lobsters of treatment C showed a slight development compared to spiny lobsters of treatments A and B (P > 0,05). On the other hand, increment of cephalotorax (mm) and total (mm) length, showed alternation among the treatments. The value of these increments were slight lower for the treatment C (P > 0,05), respectively. The results of increments in treatment B showed slight better in relation to the treatment A and C(P > 0,05) respectively. The bromatological analyze of food in treatment B showed higher protein, lipid and carbohydrate value and the diet of treatment C showed lower value, respectively. The spiny lobster of treatment A, B, and C showed almost the same number of moults and intermoult periods (P > 0,05). The survival rate was also closed each other, and in some treatments almost the same (P > 0,05). We concluded that early juvenile spiny lobster P. laevicauda can be fed on diets used in this experiment. In addition the individuals accepted commercially formulated shrimp feeds. This fact contribute to the development of the methodology on the culture of lobsters, with speculation on the possible adaptations that can be useful to the final development of commercially incomeproducing units. / A lagosta é um recurso pesqueiro de grande importância econômica para o Estado do Ceará. Esta atividade teve seu início na década de 50 e de lá para cá, vários tipo de embarcações e artes-de-pesca foram utilizadas para a captura deste recurso. No entanto, com o início da exploração deste crustáceo, veio consequentemente a diminuição dos estoques naturais, e isto, devido a grande demanda do setor pelo produto, que forçou dessa maneira a exploração deste recurso. Atualmente, esta atividade esta em forte declínio e uma das formas para reverter esse quadro seria através da aqüicultura, ou seja, do cultivo de nossas espécies em cativeiro. O presente trabalho teve como objetivo de avaliar o desenvolvimento de juvenis recentes da lagosta espinhosa Panulirus laevicauda, alimentadas com os moluscos Perna perna, Mytella falcata e ração comercial para camarão marinho + biomassa de Artemia sp., em condições de laboratório. Este experimento foi realizado nas instalações do Centro de Tecnologia em Aquicultura da Universidade Federal do Ceará, em um período de 122 dias. Este trabalho foi dividido em três tratamentos (tratamento A – P. perna, tratamento B – M. falcata e tratamento C – ração comercial + biomassa de Artemia sp.) com quatro repetições cada. A taxa de densidade inicial utilizada foi de um indivíduo por repetição. Os alimentos foram ofertados de acordo com 10% da biomassa dos indivíduos. Durante o experimento foram realizadas as análises bromatológicas dos alimentos, sendo verificados as quantidades de proteínas, lipídeos, cinzas, carboidratos e umidades. Os parâmetros físico-químicos (pH, temperatura e salinidade) foram observados diariamente e as biometrias (peso, comprimento do cefalotórax e total) mensalmente. Diariamente, se observava a ocorrência de mudas nos tratamentos com os seus respectivos dias. Após o término do experimento os parâmetros físico-químicos, os dados biometricos, os números de mudas, as freqüências de mudas e as taxas de sobrevivência foram analisadas por testes estatísticos. Os testes estatísticos utilizados foram o Kolmogorov-Smirnov e o teste “t” de Student (parâmetros físico-químicos), a Análise de Variância (ANOVA) e se necessário o teste de Tukey (biometrias, número de mudas, período de intermudas) e o teste do Qui-quadrado de Pearson (sobrevivência), respectivamente. Os níveis de significância utilizado nos testes estatísticos foram de µ = 0,05. Os parâmetros físico-químicos deste trabalho mostraram valores mínimos, máximos e médios muito próximos entre si. Com a realização do teste de Kolmorogov-Smirnov, o mesmo mostrou que o pH, temperatura e salinidade, atenderam a suposição de normalidade. Ao comparar estes parâmetros com o teste “t” de Student, foi verificado que não houve diferença estatística significativa entre os tratamentos (P > 0,05). Ao analisamos os resultados do crescimento em peso (g), ganho de peso (g), crescimento do comprimento do cefalotórax (mm) e do comprimento total (mm) em valores brutos, observamos que as lagostas do tratamento C apresentaram um ligeiro desenvolvimento em comparação aos tratamentos A e B (P > 0,05). Por outro lado, os ganhos de comprimento do cefalotórax (mm) e do ganho de comprimento total (mm), apresentaram alternância entre os tratamentos, sendo que os valores destes ganhos foram um pouco menor para o tratamento C (P > 0,05). Todos os incrementos aqui analisados seguiram as seguintes seqüências, o tratamento B apresentou-se um pouco melhor em relação aos tratamentos A e C (P > 0,05). As análises bromatológicas da dieta do tratamento B apresentaram valores de proteína, lipídeos e carboidratos mais altos em relação ao tratamento C que apresentou os valores menores entre as dietas, respectivamente. As lagostas do tratamento A, B e C, apresentaram praticamente o mesmo número de mudas e o período de intermudas (P > 0,05). A taxa de sobrevivência foi também bastante próxima uma da outra, chegando em alguns tratamentos serem praticamente iguais (P > 0,05). Concluirmos que os alimentos utilizados neste experimento podem ser utilizados na alimentação de juvenis recentes da lagosta espinhosa P. laevicauda. Outro resultado animador obtido neste trabalho foi à aceitação pela lagosta da dieta artificial, já que uma das grandes problemáticas em um projeto piloto de cultivo de nossas espécies, seriam a aceitação das mesmas por uma dieta peletizada.

Aim of the thesis is to evaluate health in selected pig stock. Adherence to vaccination programs and good veterinary prevention principles, provision of appropriate stall, good care and feeding, piglets wean timing, selection of breeding animals, choosing of reliable personnel and other factors have great impact on health in pig stock. Considering above mentioned factors, the aim of the thesis was to asses health of sows, piglets and fattening pigs in chosen farm Ponědraž ltd. and asses influence of vaccination on production in time period 2010 to 2011. Further it was neccesary to asses observance of good hygiene praxis in enterprise, including using of hygiene loop by personnel and to find out, if the enterprise is equiped with systematic protection against infectious diseases. To evaluate stall by pig categories, animal welfare and positive influence on health and increase of pig production as a whole. Further to asses compliance with EU legislation. Aim of the thesis is to evaleuate new vaccination scheme against respirational diseases, it´s influence on increase of production and improving of healt in observed stock. In the end are all above mentioned requirements evaluated.

Cattle breeding is one of the part of traditional Czech agriculture. It is a vital part of economy consisting of two main branches - milk and beef production. Beef is one of the main products of cattle breeding sometimes provided by fattening of heifers, cows and bulls. Producing meat with the highest quality with low costs is the main goal of fattening the cattles. I have tested the influence of selected fators on the fattening capacity and carcass values of Czech Fleckvieh bulls in the control station as well as the economic requirements of the fattening period. I have compared the test period of 530 ? 10 days with period of 610 ? 10 days of fattening using the old and new technology of supplementation. Further fattening was provided by results of growing Charolais, Limousin and Czech Fleckvies x Simmental bulls. The results suggest that the increase of the period of fattening for 80 days had a positive effect on carcass yield (p < 0.001), assigning in the classification according to SEUROP and profitability of farming. The positiv relationships between breeding value of fathers and carcass yield of their sons was observed. Finally, the positive influence of new technology of fattening on the classification acording to SEUROP was shown.

A growing number of pure-bred herds of beef breeds began to grow a herd of cows with a dual-purpose efficiency type, farmers often use their crosses with beef breeds of cattle to increase their meat performance. The aim of this diploma work was to analyse results of fattening ability and carcass value of Czech Pied Cattle bulls (C) and their crosses with beef breeds. In evaluation selected indicators were included 907 slaughtered bulls dividing according their genotype. The software programs Microsoft Excel and Statistica has been used for processing calculations and the statistic data. An important indicator is achieved dressed carcass weight (DCW), which was highest in bulls Meat Siemental (SI) 370.1 kg, Aberdeen Angus (G) 359.0 kg and crossbreeds Charolais and Czech Pied Cattle (TxC) 354.2 kg. Lowest DCW had extensive breed Highland (E) and Galloway (W) 318.8 kg. The difference between SI and E + W was 51.3 kg and was highly statistically significant (P {$\leq$} 0.001). The group of TxC and TxH and breed Piemontese (P) had the highest intensity of growth, net gain was 671.5 g, resp. 669.6 g for T and crosses and 652.5 g for the breed P. The lowest average net gain was found in the breed G (531.3 g). The highest production of first quality meat was found in the breed P (55.6 kg), 55.4 kg was achieved in breed SI. At least meat I. grade was found in bulls of E and W (47.2 kg). Significant difference was found between SI and E + W at a significance level P {$\leq$} 0.001. Based on the results we can recommend commercial crossings Czech Pied cattle with bulls meat breed or breeding pure-bred beef breeds. It is important to take into account the specificity of each breed, its earliness and size of body frame in the choice of slaughter weight and age of fattening bulls, to avoid unwanted growth of fat in bulls, and to realize the slaughter weight trough the most intensive fattening.

Ziel der Dissertation war die Überprüfung der klinischen Wirksamkeit von Natriumsalicylat bei respiratorischen Erkrankungen von Mastputen unter Feldbedingungen. Bisher existieren keine konkreten Richtlinien bzw. Modelle zum Versuchsaufbau beim Geflügel, und explizit bei der Pute, zur Durchführung einer derartigen Studie. Daher stellten sowohl die Konzeption als auch die Implementierung eines Studiendesigns zur Untersuchung der Wirksamkeit eines Antiphlogistikums bei der Mastpute unter Feldbedingungen eine zusätzliche elementare Zielsetzung dieser Promotion dar. Die in dieser Dissertationsschrift entwickelten Feldstudien orientieren sich an den Leitlinien der good clinical practice sowie der guideline for the conduct of efficacy studies for non-steroidal anti-inflammatory drugs und entsprechen der Wertigkeitsklasse Ia der evidenzbasierten Veterinärmedizin. Jede der drei Feldstudien wurde als kontrollierte, randomisierte und verblindete Parallelgruppenstudie in verschiedenen Regionen Deutschlands durchgeführt und gliederte sich in eine viertägige experimentelle Phase (EP) und eine siebentägige postexperimentelle Phase (PoP). Die zunächst definierten Arbeitshypothesen bekamen entsprechende Beurteilungskriterien zugewiesen. Unter deren Nutzung erfolgte die spätere Evaluierung, inwieweit die entzündungshemmende Wirkung von Natriumsalicylat imstande war, den Heilungsprozess der respiratorischen Grunderkrankung zu beschleunigen und eine verbesserte restitutio ad integrum hervorzurufen.

<p>Apple pomace is a by-product of the industrial production of apple juice, amounting to approximately 20-30% of freshly processed apples. Several million tonnes of apple pomace is produced in the world annually. Fresh apple pomace is characterised by high sugar and moisture content, which makes it susceptible to microbial contamination, uncontrolled fermentation and spoiling. Despite increasingly stricter legal regulations in managing biodegradable waste, large quantities of apple pomace are still being disposed of at landfills, posing a serious environmental issue. Since apple pomace has a certain nutritive value, it seems necessary to consider possibilities for using it as animal feed.<br />The main goal of this research was to examine the possibility for using dried apple pomace as animal feed, i.e., as a raw material in the industrial production of animal feed. Accordingly, the nutritive value of dried apple pomace was examined, along with the process of pelleting, since pelleting is one of the most common technological procedures in the industrial production of animal feed.<br />The testing of the chemical composition of dried apple pomace, used to determine its nutritive value, included the analyses of the content of raw proteins, raw fats, raw fibres, ash, neutral detergent fibres (NDF), acid detergent lignin (ADL), lignin, total sugars, individual sugars &ndash; fructose, glucose and sucrose, essential amino-acids, vitamins and mineral elements. When compared with the majority of commonly used animal feeds, the dried apple pomace was found to contain large amounts of raw fibres and sugars and small amounts of proteins and fats.<br />In accordance with the determined nutritional composition of the dried apple pomace, concentrate mixtures for fattening pigs were prepared, after which a trial was performed to examine the effect of feeding the animals on the mixtures containing dried apple pomace in different concentrations on the production performance of the fattening pigs. The results of the feeding trial showed that adding 7% of dried apple pomace in the growing period and 10% in the finishing period had no negative effects on the animal health, production and meat yield.<br />In the next part of the research, the dried apple pomace was pressed into pellets, with three starting moisture contents in the unpelleted material &ndash; 10%, 13% and 16%. The examination of the produced pellets showed that they had very good physical quality in terms of the pellet durability index (PDI) and hardness. The value of PDI exceeded 99% for all three starting moisture contents. The bulk density of the pelleted dried apple pomace was nearly twice as large as it was before pelleting. Increasing the moisture content in the dried apple pomace from 13% to 16% resulted in lower temperatures and energy consumption in the process of pelleting.<br />The goal of the next part of the research was to examine the effect of adding apple pomace into the concentrate mixture models consisting of corn and sunflower meal on the physical quality of the obtained pellets, the specific electricity consumption of the pellet press and the temperature of the pellet press die. Three concentrate mixture models were prepared for the test, comprising 0%, 10% and 20% of dry apple pomace. The mixtures were conditioned by adding water to reach the moisture content of 13%, 15% and 17% and pelleted at three settings of the press die (8, 24 and 30 mm). Therefore, three parameters were varied at three levels, in a full factorial experimental design. The dependent variables (response variables) were: PDI, pellet hardness (H), dust content in the pellets, bulk density of the pellets, matrix temperature of the pellet press and the specific energy consumption of the pellet press. The results showed that adding dried apple pomace into the model concentrate mixtures led to a significant increase in pellet quality, especially in terms of increasing the PDI value and decreasing the dust content. The results of the analysis of standard scores (SS) showed that the optimum values for pellet quality, specific energy consumption and temperature of the press die were obtained for the model concentrate mixture containing 10% of dried apple pomace, using 30 mm press die and with 17% of the starting moisture content. Good results were also obtained for the model concentrate mixture containing 20% of dried apple pomace, using 24 mm press die and with 17% of the starting moisture content.<br />To define the effect of the concentration of dried apple pomace in the model mixtures, the press die thickness and the starting moisture content on the change of the response variables, the response surface methodology (RSM) was used. The analysis of variance (ANOVA) of the response models for each of the analysed quality parameters and pelleting processes, showed which of the process parameters (percentage of apple pomace in the concentrate model mixtures, press die thickness and starting moisture content) had statistically the biggest effect on creating the mathematical response models, presented in the form of the second order polynomial (SOP). The results of this research showed that the increase in the percentage of dried apple pomace, press die thickness and starting moisture content led to an increase in PDI value, hardness (H) and bulk density of the pellets and a decrease in the content of dust in the pellets. The increase in the share of apple pomace in the model mixtures and in the die thickness of the pellet press led to an increase in the specific energy consumption and die temperature. On the other hand, the increase in the starting moisture content led to a decrease in the specific energy consumption and die temperature.<br />In the last part of the research, on the basis of the determined nutritive value of the dried apple pomace the author made a calculation, in terms of optimising the concentrate mixtures containing dried apple pomace in the optimum amount for feeding particular species and categories of farm animals. The results suggest the way of practical utilization of dried apple pomace in feeding farm animals as well as in the industrial production of animal feed.</p>

Aquest treball de tesis doctoral tracta de la Optimització de la fase d'engreix. L'objectiu és determinar les condicions d'enviament a sacrifici d'un lot d'animals des d'un punt de vista operatiu. En primer lloc es fa una anàlisi de la cadena de producció de carn porcina, resaltant-ne els canvis del sector que han influit en la fase d'engreixament. La conclusió d'aquesta anàlisi és el plantejament d'un model per prendre decisions degut al canvi de paradigma que s'evidencia: els productors de porcs en la fase d'engreix cal que orientin la gestió del paràmetres operatius i els productes finals a les exigències i gustos dels seus clients. Seguidament, es presenta el sistema d'ajut a la decisió basat en un model biològic que explica l'evolució de les variables productives (pes i consum de pinso). A més també prediu les variables associades a característiques de la canal, com són el percentatge de magre, la proporció de peces, el rendiment i el greix intramuscular. El sistema té en compte tres mercats de carn porcina alternatius: 1) basat en pes viu, 2) basat en mèrits de la canal (percentatge de magre) y 3) basat en el valor de les peces nobles resultants de l'especejament de l'animal. L'objetiu del sistema és determinar la millor estratègia d'enviament per a cadascun dels genotips que s'han estudiat (alternatives de producció) depenent del mercat on seran enviats els animals. A més, també ha estat estudiat l'efecte de la variabilitat biològica dels animals dins del lot sobre els valors econòmics. També s'ha considerat l'opció d'enviar els animals en diverses etapes per tal d'homogeneitzar el pes dels animals enviats. Aquest problema ha estat estudiat seguint l'enfocament de programació dinàmica. En els darrers capítols es presenten quatre aplicacions del model que s'han desenvolupat al llarg del treball. En un futur els mercats de carn porcina tindran la tendència a ser més definits, per tant la producció en la fase d'engreixament porcí hauria d'integrar i tenir en compte les demandes i les exigències del consumidor. / This PhD Thesis is related to optimisation of pig fattening phase under an operative point of view. Firstly it has been an analysis of the Pork Chain in order to establish a framework. The objective is to highlight the changes in the sector which have influenced on fattening phase. The result was the necessity of satisfying the consumer demands. In the following chapters a Decision Support was developed based on the consumers requirements. Based on a biological model, a managerial model has been developed to analyse the fattening phase. The decision support system takes into account three alternative pig meat markets: Live body weight pricing, carcass merit pricing, and components or cuts pricing system. Apart from the alternatives markets, its objective is to determine the best marketing strategy for each different genotypes (production alternatives) depending on the market where they will be sent. In addition, the effect of animal variability on economic figures has been studied. Also it has been considered the option of marketing the animals in different stages in order to homogenise the weight of animal sent. This problem has been treated under dynamic programming framework. In near future pig meat markets are going to be more defined, therefore the fattening phase of pork production must take consumer demands into account.