Made available in DSpace on 2015-03-26T13:42:24Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1800419 bytes, checksum: 3fadb87455bb2fa082c397f8824173aa (MD5) Previous issue date: 2012-02-16 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O objetivo do estudo foi identificar genes codificantes para os complexos enzimáticos da cadeia tranpostadora de elétrons (CTE) que apresentam-se diferencialmente expressos no músculo Longissimus dorsi (LD) de suínos bem como seus padrões de expressãos de acordo níveis de fósforo disponíveis (Pd) na dieta e ambientes térmicos em duas fases de crescimento. Dois experimentos foram realizados utilizando-se 48 suínos de alto potencial genético para deposição de carne em duas diferentes fases de crescimento: a fase 1 de 15 a 30 kg e fase 2 de 30 a 60 kg. Estas experimentos foram construidos em modelo fatorial 2 X 3 (2 diferentes temperaturas ambientais X 3 níveis de Pd na dieta) constituindo 6 tratamentos em cada fase de crescimento. Vinte e quatro suínos da fase da 1 (15 a 30 kg) com peso inicial de 15 ± 0,41 kg, foram distribuídos em delineamento inteiramente casualizado, com 6 tratamentos e 6 repetições. Estes animais foram alojados ou no ambiente termoneutro (24,5 ± 1,2 º C e umidade relativa em 76,3 ± 8,5%) ou no ambiente de calor (34,1 ± 0,8 º C e umidade relativa em 70,1 ± 8,1%) e, em seguida, distribuídos para um dos 3 níveis de Pd na dieta (0.107, 0.321 ou 0.535%). Vinte e quatro suínos da fase de 2 (30 a 60 kg) com peso inicial de 30,19 ± 0,30 kg, foram distribuídos em delineamento inteiramente casualizado com 6 tratamentos e 6 repetições. Estes animais foram alojados ou ambiente termoneutro (21,9 ± 1,4 º C e umidade relativa em 76,9 ± 5,7%) ou ambiente de calor (31,6 ± 0,7 º C e umidade relativa em 72,8 ± 5,9%) e, em seguida, distribuídos para um dos 3 níveis de Pd na dieta (0.116 , 0.306 ou 0.496%). Os perfis de expressão dos genes ND1, ND2, SDHD, CYTB, COX1, COX2, COX3, ATP5J2 e ATP6 foram analisados pelo PCR quantitativo em tempo real (qRT-PCR) a partir de amostras de LD. Os genes ND1, ND2, CYTB, COX1, ATP5J2 e ATP6 foram menos expressos (P< 0.05) nos suínos da fase 1 mantindo em estresse por calor em relação aqueles mantidos no ambiente termoneutro. Nos suíno da fase 2 de crescimento que estavam mantidos em estresse por calor apresentaram redução (P < 0.05) na expressão dos genes ND2, SDHD, CYTB, COX1, COX2, COX3, ATP5J2 e ATP6, em relação aqueles submetido ao ambiente termoneutro. A menor expressão desses genes nos suínos estressados por calor, prove evidências dos efeitos das altas temperaturas sob o metabolismo oxidativo a fim de reduzir a produção de calor o que refletiu na redução da exigência de consumo diário de fósforo. Parte desse efeito pode estar associado a concomitante redução do consumo vonlutário e outra parte é sugerido ser devido ao aumento da produção de espécies reativas de oxigênio (ROS) nas mitocôndrias induzido pelo estresse por calor. Quanto a mudança nos padrões de expressão desses genes entre os níveis de Pd, verificou-se que nos suínos da fase 1, os genes ND1, ND2, CYTB, COX1, ATP5J2 e ATP6 mostraram-se diferencialmente expressos (P<0.05) entre os níveis de Pd no ambiente termoneutro e o gene ND2 no ambiente de calor (P<0.05). Nos suínos da fase 2, os genes COX3 e ND2 foram diferencialmente expressos (P<0.05), respectivamente, entre os níveis de Pd no ambiente termoneutro e ambiente de calor. Os dados apresentados revelam uma forte evidência de que o nutriente fósforo é um dos fatores chave que regulam a fosforilação oxidativa com implicação direta sobre a performance animal. Para a confirmação dessa hipótese de que suínos estressados por calor apresentam aumento na produção de ROS, foi realizado um segundo experimento que objetivou avaliar o perfil de expressão dos genes associados sistema antioxidante (manganes- superóxido dismutase, glutathiona peroxidase e catalase) em suínos de 2 diferentes fases de crescimeto submetido à ambientes de termoneutralidade e estresse por calor. Baseado em análises de qRTPCR, estes genes foram significativamente mais expressos em suínos expostos ao estresse de calor. Em geral, os dados deste estudo são os primeiros a revelar os efeitos de diferentes níveis de fósforo disponível na expressão de genes relacionados com a fosforilação oxidativa e suas implicações sobre o desempenho de suínos. Além disso, é demonstrado que elevadas temperaturas não só induzem a redução da capacidade metabólica oxidativa, como também, estimulam a produção de ROS em mitocôndrias de músculo LD o que leva a danos oxidativos mitocondriais, tais como, repressão da transcrição e provavelmente redução na atividade dos complexos da cadeia transportadora de elétrons, o que refletiu na piora da performance animal. Tais informações irão contribuir para melhor compreensão do papel do fósforo no metabolismo energético e maior entendimento sobre as mudanças no metabolismo e funcionamento mitocondrial em resposta à altas temperaturas. / The purpose of this study was to identify genes encoding the electron transport chain (ETC) complexes that are present differentially expressed in the Longissimus dorsi (LD) of pigs and their expression patterns according to levels available of phosphorus (aP) in the diet and thermal environment in the two different growth phase. Two experiments were carried out using 48 higher-lean growth pigs from two different growth phases: phase 1 from 15 to 30 kg and phase 2 from 30 to 60 kg. These experiments were designed as a 2 x 3 (2 different environment temperatures X 3 levels of dietary aP) factorial treatments comprising of 6 treatments and each growth phase. Twenty -four pigs from growth phase 1 (15 to 30 kg) with initial weight of 15 ± 0.41kg, distributed in a completely randomized design with 6 treatments and 6 replications. These pigs were allotted to either thermoneutral (24.5 ± 1.2ºC and RH at 76.3 ± 8.5% or heat stress (34.1 ± 0.8ºC and RH at 70.1 ± 8.1%) and then allotted to one of the 3 levels of dietary aP (0.107, 0.321 or 0.535%). Twenty-four pigs from growth phase 2 (30 to 60 kg) with initial weight of 30.19 ± 0.30 kg, distributed in a completely randomized design with 6 treatments and 6 replications. These pigs were allotted to either thermoneutral ( 21.9 ± 1.4ºC and RH at 76.9 ± 5.7%) or heat stress (31.6 ± 0.7ºC and RH at 72.8 ± 5.9%) and then allotted to one of the 3 levels of dietary aP (0.116, 0.306 or 0.496%). The expression profiles of ND1, ND2, SDHD, CYTB, COX1, COX2, COX3, ATP5J2 and ATP6 genes were analyzed by quantitative real-time PCR from samples of LD. The ND1, ND2, CYTB, COX1, ATP5J2 and ATP6 genes showed reduce expression (P<0.05) in phase 1 pigs maintained under heat stress compared to those kept in thermoneutral environment. In pigs from growth phase 2 maintained under heat stress, the ND2, SDHD, CYTB, COX1, COX2, COX3, ATP5J2 and ATP6 genes showed reduce expression (P<0.05) compared to those kept in thermoneutral environment. The lower expression of these genes in pigs exposed to high temperatures provides evidence of the effect of heat stress by decreasing oxidative metabolism (oxidative phosphorylation) in order to reduce heat production, which reflecting on reduction of requirement for daily aP intake. Part of this effect is associated with concomitant reduction in voluntary feed intake and another part is suggested to be due to an increased production of reactive oxygen species in the mitochondria induced by heat stress resulting in downregulation of these genes. Significant different levels of expression were observed across aP levels. In pigs from growth phase 1, the ND1, ND2, CYTB, COX1, ATP5J2 and ATP6 genes were differentially expressed across aP levels (P<0.05) in the thermoneutral and ND2 gene in the hot environments. In pigs from growth phase 2, COX3 and ND2 genes were respectively differentially expressed across aP levels (P<0.05) in the thermoneutral and hot environments. These data revealed strong evidence that phosphorus is one of the key factors that regulates oxidative phosphorylation with direct implications on animal performance. To confirm the hypothesis that heat-stressed pigs have enhanced production of ROS, we performed a second experiment focused to identify changes in expression of genes encoding antioxidant systems (manganese superoxide dismutase, glutathione peroxidase e catalase) in pigs from high lean meat deposition at 2 different growth phases (15 to 30kg and 30 to 60kg) submitted to hot and thermoneutral environments. Based on qRT-PCR analyses, these genes were significantly upregulated in heat-exposed pigs. In general, data from this study are the first to reveal the effects of dietary phosphorus levels on gene expression related to oxidative phosphorylation and its implications on animal performance. Moreover, it is shown that high temperatures not only causes reduction in oxidative metabolic capacity, but also stimulate the ROS production in LD mitochondria which leading to oxidative damages, such as, repression of transcription of ETC complexes and likely reducing their activity in the mitochondria, which resulted in worse pig performance. The results obtained with this study will contribute to better understand the role of phosphorus in energy metabolism and will bring new insights into the comprehension of the changes metabolism and mitochondrial functioning in response to high temperature.

No description available.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Two studies were carried out to evaluate, trough meta-analysis, the relationship between parasitosis and animal performance of broiler and growing pigs. Databases totaled 43,976 broilers (69 articles published between 1982 and 2010) and 1,279 growing pigs (18 articles published between 1971 and 2010). Meta-analyses followed three sequential analyses: graphic, correlation and variance-covariance. Pigs challenged by endoparasites presented reduction (P<0.001) of 5% on feed intake and 31% on weight gain. Broilers challenged by E. acervulina and E. tenella presented feed intake similar (P>0.05) to control group. However, the groups challenged by E. maxima and Pool presented increase on feed intake by 27% and 5% compared to control group. In relation to broilers weight gain, all challenged groups presented reduction (P<0.05) compared to control group. The average reduction was 10%, with the exception of the group challenged by E. maxima which showed a 23% reduction in daily weight gain compared to control group. The average age and average body weight of challenged animals, and the crude protein intake were the variables that most adjusted the determination coefficient in the equations for estimating the weight gain of parasitized pigs. Considering parasitized broilers, the reduction in feed intake was the variable that best explains the reduction in weight gain. Variance decomposition showed that parasitosis were responsible by a 6% reduction in weight gain for pigs and coccidiosis were associated by less than 1% for broilers. In addition, this analysis showed that most of the variation in weight gain was explained by the variation in feed intake (59% in pigs and 91% in broilers, on average). Parasitosis influences the performance of broilers and pigs. However, the magnitude of these effects varies with the parasite species, sex, age and line of the animal as well as nutritional factors. / Dois trabalhos foram desenvolvidos com o objetivo de estudar, através de meta-análise, a relação das parasitoses com o desempenho de frangos de corte e suínos. As bases de dados totalizaram 43.976 frangos de corte (69 artigos, publicados entre 1982 e 2010) e 1.279 suínos (18 artigos, publicados entre 1971 e 2010). A meta-análise foi realizada através de três análises sequenciais: estudos gráficos, de correlação e de variância-covariância. Suínos desafiados por endoparasitas apresentaram (P<0,001) redução de 5% no consumo de ração e de 31% no ganho de peso. Frangos de corte desafiados por E. acervulina e E. tenella apresentaram consumo de ração semelhante (P>0,05) em relação ao grupo controle. Já os grupos desafiados por E. maxima e Pool apresentaram aumento (P<0,05) no consumo de ração de 27% e 5% em relação ao grupo controle. Em relação ao ganho de peso dos frangos, todos os grupos desafiados apresentaram redução (P<0,05) quando comparados com o controle, A redução foi em média de 10%, com exceção do grupo desafiado por E. maxima que apresentou 23% de redução no ganho diário de peso em relação ao grupo controle. A idade média e o peso médio dos animais desafiados, bem como o consumo de proteína bruta, foram as variáveis que mais ajustaram o coeficiente de determinação nas equações para estimar o ganho de peso dos suínos parasitados. Para os frangos de corte parasitados, a redução no consumo de ração foi a variável que melhor explicou a redução no ganho de peso. Por decomposição da variância, foi verificado que as endoparasitoses foram responsáveis por 6% da redução no ganho de peso para os suínos, e as coccidioses foram responsáveis por menos de 1% para as aves. Além disso, a decomposição da variância mostrou que a maior parte da variação no ganho de peso foi explicada pela variação no consumo de ração (59% nos suínos e, em média, 91% nas aves). As parasitoses influenciam o desempenho dos frangos de corte e suínos. No entanto, a magnitude destes efeitos varia com o a espécie de parasita; o sexo, a idade e a linhagem do animal; bem como com fatores nutricionais.

Die Freilandhaltung von Schweinen bietet eine interessante Möglichkeit, artgerechte Schweinehaltung wirtschaftlich konkurrenzfähig zu betreiben. Problematisch erscheint bei dieser Haltungsform ihre Umweltverträglichkeit, speziell die vermutlich zu hohen N-Eintragsmengen mit der Gefahr der Stickstoffauswaschung. Ziel dieser Arbeit war es, den N-Eintrag zu untersuchen und Möglichkeiten zu finden, ihn zu beeinflussen. Dazu wurde der Nmin-Gehalt des Bodens unter verschiedenen Bedingungen in drei ausgewählten Betrieben und der Versuchsstation der Humboldt-Universität untersucht. Die Untersuchungen erfolgten über einen Zeitraum von zweieinhalb Jahren jeweils vierteljährlich Ende Februar, Ende Mai, Ende August und Ende November. Die Proben wurden nach DIN-Vorschrift in drei Schichten (0-30 cm, 30-60 cm und 60-90 cm Bodentiefe) entnommen und in der LUFA Halle auf ihren Nmin-Gehalt untersucht. Außerdem wurde untersucht, welche Einflußmöglichkeiten für den Betreuer durch geeignete Maßnahmen bestehen, und inwiefern das Verhalten der Tiere selbst ausgenutzt werden kann, um überhöhte N-Einträge zu vermeiden. Nach Auswertung der vorliegenden Untersuchungsergebnisse erscheint es keinesfalls notwendig, die Besatzdichten auf unter 6 Sauen je Hektar zu beschränken. Dies würde auch die Wirtschaftlichkeit der Haltungsform in Frage stellen. Eine durchdachte Gehegegestaltung und kürzere Belegungszeiten mit schnellem Folgefruchtanbau sind entschieden wirksamer als nur sehr niedrige Besatzdichten. Ein Teil der aufgezeigten verfahrenstechnischen Möglichkeiten zur Vermeidung von Stickstoffverlusten wurde bereits während der Untersuchungen erfolgreich in der Praxis erprobt. / Outdoor pig production offers an interesting possibility to operate taking just pig attitude economially competitively. A problem of this posture form seems to be her environment compatibility, special the presumably too high N entry set with the danger of nitrate leaching. It was aim of the work in hand to examine the N entry and to find possibilities to influence him. To this the Nmin content was examined under different conditions in three select farms and in the experiment station of the Humboldt-University. These examinations were carried out via a period of time of 2.5 years respectively quarterly end february, end may, end august and end november. The soil samples became taken after DIN-regulation in three layers (0-30 cm, 30-60 cm and 60-90 cm ground depth) and in the LUFA Halle on hers Nmin salary examines. In addition, you examined to avoid which possibilities excessive N entries pass by the attendant or by useage of the animal behavior. After evaluation of the examinations it seems under no circumstances necessary to demand stocking rates of lower than 6 sows per hectare. This would put the economicalness of the posture form in question. An enclousure lay-out thought through, the occupancy time and fast following fruit cultivation are decided more effectively than only very low edging densities more briefly. A part of the shown method technical possibilities for the avoidance of nitrogen losses was already tested successfully during the examinations in the practice.

Thesis (MScEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Food security is a national priority, according to Section 27 of the South African Constitution. It states: “Every citizen has the right to have access to sufficient food and water, and that the state must by legislation and other measures, within its available resources, avail to progressive realisation of the right to sufficient food.” Nevertheless, while food security is clearly a government priority and regardless of the country being considered as self-sufficient in respect of food production, food insecurity remains a dire South African challenge. This study presents the improvement of smallholder pig farmers to a commercial standard with funding from the government as a potential means to address poverty and food insecurity in South Africa. Commercial standard pig farms as opposed to smallholder pig farms provide increased employment, food production, biosecurity and food safety. This investigative study evaluates the economic feasibility of a smallholder commercial pig farm in the Mamre area. The Empolweni community’s pig farmers serve as the case study and as an example of a typical smallholder pig farming community. Their current operations are studied, the requirements for a conversion to a commercial standard are assessed and the profitability and sustainability of the proposed commercial model is judged. The study’s findings indicate that specific scenarios (high production performance, large pig farm unit sizes, pork price increases or feed costs reductions) a commercial smallholder pig farm can achieve economic feasibility. However, trends indicate that there is low likelihood of the required conditions to achieve economic feasibility will be able to occur. The thesis judges only the potential economic feasibility of the case study, as opposed to the economic feasibility of commercial smallholder pig farmers on a national or regional level. / AFRIKAANSE OPSOMMING: Voedsel sekuriteit is ‘n nasionale prioriteit en vorm deel van die Artikel 27 Grondwetlike regte in Suid-Afrika. Die Grondwet stel dat elke landsburger die reg op toegang tot voldoende voedsel en water het en dat die staat deur middel van wetgewing en ander maatreëls, binne sy beskikbare middele, progressiewe verwesenliking van die reg op voldoende voedsel moet laat geskied. Nietemin, alhoewel voedsel sekuriteit ongetwyfeld ‘n prioriteit van die regering is en ten spyte daarvan dat Suid-Afrika as selfonderhoudend ten opsigte van voedselproduksie gesien word, heers onvoldoende voedsel sekuriteit steeds. Hierdie studie stel die volgende moontlike oplossing voor: Suid-Afrikaanse kleinskaalse varkboere moet hul bedrywighede opgradeer na 'n kommersiële standaard. Verskeie redes kan gegee word waarom hierdie oplossing 'n gangbare opsie bied om armoede en voedselsekuriteit in Suid-Afrika teë te werk. Kommersiële varkboere, in teenstelling met kleinskaalse varkboere, bied verhoogde vlakke van voedselproduksie, werkskepping, biosekuriteit en veiliger voedingsbronne. Hierdie studie poog om die ekonomiese gangbaarheid van ‘n kleinskaalse kommersiële varkplaas in die Mamre omgewing te bepaal. Die Empolweni gemeenskap se varkboere dien as 'n gevallestudie van ‘n tipiese kleinskaalse varkboerdery gemeenskap. Hul huidige bedrywighede is ondersoek, die benodighede vir ‘n opgradering is bepaal en die winsgewendheid en volhoubaarheid van die kommersiële model is beoordeel. Bevindings toon dat vir spesifieke gevalle (hoë produksievlakke, groot varkplaaseenhede, varkprys verhogings en voerkoste verlagings) ‘n kommersiële kleinskaalse varkplaas ekonomiese gangbaarheid kan behaal. Alhoewel, tendense toon dat daar ‘n lae waarskynlikheid is dat die nodige kondisie om ekonomiese gangbaarheid te behaal sal kan plaasvind. Die tesis oorweeg slegs die ekonomiese gangbaarheid van die gevallestudie. Die ekonomiese gangbaarheid van kleinskaalse varkboere op ‘n nasionale of streeksvlak word dus nie ingesluit nie.

Salmonella est une bactérie zoonotique qui représente un problème majeur de santé publique. Le porc est identifié comme l'un des principaux réservoirs de Salmonella. L'objectif de ces travaux de recherche était d'identifier les mesures prioritaires à mettre en place afin de limiter la présence de Salmonella dans la filière porcine réunionnaise. Près de 80% des élevages de porcs investigués étaient infectés par Salmonella en fin d'engraissement. Cette infection asymptomatique est associée à plusieurs facteurs de risque : les conditions géo-climatiques (altitude et pluviométrie), la production de volailles sur le site, la taille de l'élevage et la présence de salmonelles dans les salles avant l'entrée du lot. Le suivi longitudinal a d'ailleurs mis en évidence que les salmonelles résiduelles étaient la principale source d'infection, que ce soit pendant l'élevage, le transport et l'attente. Ces résultats soulignent l'importance d'améliorer l'efficacité des protocoles de nettoyage et de désinfection. La faune sauvage semble également impliquée dans l'épidémiologie de Salmonella dans la filière porcine. Une forte similarité génétique a été observée entre les souches isolées de rongeurs et de cafards et celles isolées des porcs. Par ailleurs, une prévalence en Salmonella de 16,5% dans les saucisses à base de porc démontre que Salmonella dans la filière porcine peut représenter un risque pour la santé humaine à La Réunion. Ces travaux de recherche démontrent la nécessité d'agir aux différents maillons de la filière porcine. En outre, une lutte globale doit être envisagée, incluant les différentes filières, les industriels, les services vétérinaires et les pouvoirs publics. / Salmonella is a zoonotic bacterium that represents a public health burden all over the world. Pig is considered as one of the main reservoir of this pathogen. The goal of this research project was to identify the main measures that would limit the presence of Salmonella in the Reunionese pig production. Nearly 80% of the pig farms investigated were infected with Salmonella at the end of the fattening period. This asymptomatic infection was associated with several risk factors: geo-climatic conditions (altitude and rainfall), poultry production on the same site, the size of the farm and the presence of residual Salmonella in rooms before the loading of the pig batch. Furthermore, the longitudinal investigation highlighted that environmental residual Salmonella were the main source of infection whether at farm, during the transport and the lairage of pigs. These results strengthen the importance of improving efficiency of cleaning and disinfection procedures. The wild fauna of Reunion Island seems to be involved in the epidemiology of Salmonella in the pig production, since high genetically relationships were observed between Salmonella strains isolated from rodents and cockroaches and those isolated from pigs. Otherwise, our study also highlighted Salmonella prevalence of 16.5% in pork sausages demonstrating that Salmonella in the pig production may represent a risk for public health in Reunion Island. These works stress the need to act at each stage of the pig production. Moreover, a global effort has to be considered, including professionals of the different animal production, industrials, veterinary and health services and authorities.