O transporte de grãos é de importância para a economia da Argentina. Atualmente, 84% dos grãos produzidos pelo país são transportados em rodovias, afetando sua competitividade devido a sua grande influencia nos custos.Nesse contexto, o presente trabalho tem como objetivo estudar a tomada de decisão de modo e destino dos consolidadores de grãos do Sul da Província de Buenos Aires. A partir de uma pesquisa de preferência declarada, conclui-se que a escolha de modo e destino é feita em conjunto. As variáveis relevantes para a escolha foram o preço FreeAlongsideShip no porto, o custo, a distância e a frequência do serviço. Os resultados estão em consonância com o encontrado na literatura, onde se destaca a modelagem conjunta e comportamental de diferentes etapas dos modelos de transporte e a inclusão de variáveis logísticas. Além disso, foram estimadas as elasticidades de cada alternativa e estudadas as curvas de iso-utilidade. Finalmente, foi realizada uma simulação de políticas de preço para a ferrovia, estudando a sua fatia de mercado, sua potencial arrecadação e o gasto total em transporte. / Agricultural trade is of great importance for Argentina. Nowadays, most of the crops transported by truck, affecting its competitivity because of its influence in direct costs. This study aims to analyze the choice process of the grain consolidatorsfromthe south of Buenos Aires province. From a stated preference survey, we conclude that the choice of mode and destination is made simultaneously. The relevant variables for the selection were the Free Alongside Ship price at the port, freight cost, distance and frequency. The results were consistent with those found in the literature, where behavioural joint modeling of different steps of transport models and the inclusion of logistics variables stand out. Moreover, price elasticities were estimated and iso-utility curves were studied. Finally, train price policies simulations were made observing market shares, expected incomes and total expenditures in transportation.

O transporte de grãos é de importância para a economia da Argentina. Atualmente, 84% dos grãos produzidos pelo país são transportados em rodovias, afetando sua competitividade devido a sua grande influencia nos custos.Nesse contexto, o presente trabalho tem como objetivo estudar a tomada de decisão de modo e destino dos consolidadores de grãos do Sul da Província de Buenos Aires. A partir de uma pesquisa de preferência declarada, conclui-se que a escolha de modo e destino é feita em conjunto. As variáveis relevantes para a escolha foram o preço FreeAlongsideShip no porto, o custo, a distância e a frequência do serviço. Os resultados estão em consonância com o encontrado na literatura, onde se destaca a modelagem conjunta e comportamental de diferentes etapas dos modelos de transporte e a inclusão de variáveis logísticas. Além disso, foram estimadas as elasticidades de cada alternativa e estudadas as curvas de iso-utilidade. Finalmente, foi realizada uma simulação de políticas de preço para a ferrovia, estudando a sua fatia de mercado, sua potencial arrecadação e o gasto total em transporte. / Agricultural trade is of great importance for Argentina. Nowadays, most of the crops transported by truck, affecting its competitivity because of its influence in direct costs. This study aims to analyze the choice process of the grain consolidatorsfromthe south of Buenos Aires province. From a stated preference survey, we conclude that the choice of mode and destination is made simultaneously. The relevant variables for the selection were the Free Alongside Ship price at the port, freight cost, distance and frequency. The results were consistent with those found in the literature, where behavioural joint modeling of different steps of transport models and the inclusion of logistics variables stand out. Moreover, price elasticities were estimated and iso-utility curves were studied. Finally, train price policies simulations were made observing market shares, expected incomes and total expenditures in transportation.

O transporte de grãos é de importância para a economia da Argentina. Atualmente, 84% dos grãos produzidos pelo país são transportados em rodovias, afetando sua competitividade devido a sua grande influencia nos custos.Nesse contexto, o presente trabalho tem como objetivo estudar a tomada de decisão de modo e destino dos consolidadores de grãos do Sul da Província de Buenos Aires. A partir de uma pesquisa de preferência declarada, conclui-se que a escolha de modo e destino é feita em conjunto. As variáveis relevantes para a escolha foram o preço FreeAlongsideShip no porto, o custo, a distância e a frequência do serviço. Os resultados estão em consonância com o encontrado na literatura, onde se destaca a modelagem conjunta e comportamental de diferentes etapas dos modelos de transporte e a inclusão de variáveis logísticas. Além disso, foram estimadas as elasticidades de cada alternativa e estudadas as curvas de iso-utilidade. Finalmente, foi realizada uma simulação de políticas de preço para a ferrovia, estudando a sua fatia de mercado, sua potencial arrecadação e o gasto total em transporte. / Agricultural trade is of great importance for Argentina. Nowadays, most of the crops transported by truck, affecting its competitivity because of its influence in direct costs. This study aims to analyze the choice process of the grain consolidatorsfromthe south of Buenos Aires province. From a stated preference survey, we conclude that the choice of mode and destination is made simultaneously. The relevant variables for the selection were the Free Alongside Ship price at the port, freight cost, distance and frequency. The results were consistent with those found in the literature, where behavioural joint modeling of different steps of transport models and the inclusion of logistics variables stand out. Moreover, price elasticities were estimated and iso-utility curves were studied. Finally, train price policies simulations were made observing market shares, expected incomes and total expenditures in transportation.

Dans le contexte où la consommation de viande de lapin et de veau de grain est variable et relativement faible comparativement à d'autres viandes comme celle du bœuf, du porc et du poulet, la présence de ces viandes sur le marché demande de maintenir ou d'améliorer leur qualité. La qualité de la viande peut être influencée par plusieurs facteurs, dont la gestion pré-abattage (temps de jeûne, la durée du transport et le temps d'attente à l'abattoir). Une gestion pré-abattage inadéquate peut exposer les animaux à un stress incontrôlé avant l'abattage, pouvant mener à d'importants défauts de qualité de la viande. Cette qualité est bien définie dans la littérature pour certaines espèces animales telles que le porc et la volaille, mais pour le lapin et le veau de grain, les connaissances sont limitées. Ainsi, l'objectif de cette thèse était d'évaluer l'impact des différents défis et conditions particulières de la gestion pré-abattage spécifique au lapin et au veau de grain sur la physiologie et la qualité de la viande. Une attention particulière a été mise sur le jeûne pré-abattage pour le lapin et sur le transport pour le veau de grain en réponse aux besoins spécifiques de chaque secteur. Les résultats des trois premières études ont permis de démontrer qu'un temps de jeûne de 18 h serait optimal pour permettre une vidange gastrique adéquate et une excrétion limitée d'Enterobacteriaceae dans les fèces sans impact majeur sur la qualité de la viande de lapin tant en conditions expérimentales que commerciales. La première étude a tout d'abord permis de démontrer qu'un jeûne pré-abattage inférieur à 24 h, sans les effets de la mise en cage et du transport des animaux, n'est pas particulièrement stressant pour les lapins en contexte expérimental. Néanmoins, un jeûne de 18 h serait optimal, car la présence d'Enterobacteriaceae a été observée dans les fèces des lapins mâles après 18 et 22 h de jeûne. De plus, moins d'espèces totales ont été observées et celles-ci étaient moins uniformément réparties dans le microbiome fécal des lapins ayant des jeûnes plus longs. Toutefois, le nombre limité d'Enterobacteriaceae détectée dans les fèces des lapins suggère un risque d'excrétion plus faible comparativement à d'autres espèces animales telles que le porc et la volaille. Les résultats de la deuxième étude ont démontré que, lorsque les temps de transport et d'attente à l'abattoir sont courts (30 min chacun), un jeûne de 18 h permet une vidange gastrique adéquate sans effets majeurs sur la qualité de la viande. Le sexe des lapins a aussi eu un effet limité sur la qualité de la viande lorsque les lapins étaient abattus à un poids vif inférieur à 2,65 kg. Pour la troisième étude, le jeûne ayant donné les meilleurs résultats lors du deuxième essai (18 h) a été testé en conditions commerciales en en comparaison au jeûne effectué normalement par le producteur (23 h). Les résultats ont montré que les deux temps de jeûne pourraient être adéquats, compte tenu de l'impact minimal sur la qualité de la viande ainsi que sur les microbiomes du cæcum et des fèces. Pour les veaux de grain, comme des périodes relativement longues sont nécessaires chez les bovins pour observer des effets négatifs du jeûne sur la qualité de la viande, le besoin de recherche était plutôt au niveau de la longueur et des conditions de transport des animaux jusqu'à l'abattoir. La dernière étude a permis d'observer que la qualité de la viande des veaux de grain est acceptable pour un usage commercial, mais que certains facteurs intrinsèques reliés à l'animal et les conditions pré-abattage ont des impacts importants sur la qualité de la viande. Plus particulièrement, le sexe était le paramètre mesuré ayant eu le plus d'impact sur la qualité de la viande et que, pour le longissimus et le pectoralis, le pH ultime (pH ) était plus u élevé pour les mâles. De plus, pour les veaux de grain transportés entre 8 et 307 min, une durée d'attente à l'abattoir inférieure à 120 min est préférable afin d'obtenir un pH du u longissimus plus faible. Finalement, cette dernière étude a révélé que les paramètres pré-abattage étudiés ont eu un impact plus important sur la qualité de la viande du longissimus que sur celle du pectoralis. / Given the variable and relatively low consumption of rabbit and grain-fed calf meats compared to others like beef, pork, and chicken, maintaining or improving their quality is crucial to maintain their presence in the market. Meat quality attributes can be influenced by pre-slaughter management such as feed withdrawal time, transport duration and lairage time at the slaughterhouse. An inadequate pre-slaughter management can expose animals to uncontrolled stress before slaughter, potentially leading to meat quality defects. While pre-slaughter management is well-defined in the literature for some animal species like pigs and poultry, knowledge is limited for rabbits and veal calves. Therefore, the objective of this thesis was to evaluate the impact of different challenges and specific pre-slaughter management conditions for rabbits and grain-fed calves on blood and gastrointestinal tract parameters as well as meat quality. Particular attention was given to pre-slaughter feed withdrawal for rabbits and transport conditions and duration for grain-fed calves, addressing the specific needs of each sector. The results of the first three studies suggest that an 18 h feed withdrawal time (FWT) can allow the gut to empty properly and limits the excretion of Enterobacteriaceae in feces with limited effect on rabbit meat quality under both experimental and commercial conditions. The first study demonstrated that a preslaughter FWT shorter than 24 h, without the effects of crating and transport, is not particularly stressful for rabbits. However, an 18-h FWT would be optimal, as the presence of Enterobacteriaceae was observed in the feces of male rabbits after 18 and 22 h of FWT. Additionally, fewer total species were observed, and these were less evenly distributed in the fecal microbiome of rabbits with longer FWT. Nevertheless, the limited numbers detected suggest a lower risk of fecal shedding for rabbits compared to other animal species such as pigs and poultry. Nonetheless, longer FWTs could still present the risk of fecal shedding of those undesirable organisms and contaminate the carcass at slaughter. The results of the second study showed that when transport and lairage times are short (30 min each), an 18 h FWT can allow the gut to empty properly with limited effect on rabbit meat quality. Additionally, the impact of sex on meat quality is limited when rabbits are slaughtered at a live weight lower than 2.65 kg. For the third study, the FWT that yielded the best results in the second trial (18 h) was tested under commercial conditions in comparison to the FWT normally practiced by the producer (23 h). The results showed that both FWT could be adequate, considering the minimal impact on meat quality as well as on the cecum and feces microbiomes. For grain-fed calves, as relatively long periods are necessary for observing negative effects of feed withdrawal on meat quality, we focused on the duration and conditions of transport to the slaughterhouse. The fourth study observed that the meat quality of grain-fed calves is acceptable for commercial use, but certain intrinsic animal-related factors and pre-slaughter conditions have significant impacts on meat quality. More specifically, gender had the most significant impact on pectoralis and longissimus meat quality and meat ultimate pH (pH ), for both muscles, was higher for male calves compared u to females (P < 0.001). Additionally, for calves transported between 8 and 307 min, a lairage time at the slaughterhouse shorter than 120 min is preferable to achieve a lower longissimus pH. Finally, the preslaughter parameters evaluated in this study had a lesser impact on the u pectoralis compared to the longissimus muscle.