Thèses : « Alimentazione animale »

1

Messina, Maria Rosaria <1982&gt. « Natural compounds to control clostridial and salmonella infections in food animals ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3037/1/messina_mariarosaria_tesi.pdf.

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2

Messina, Maria Rosaria <1982&gt. « Natural compounds to control clostridial and salmonella infections in food animals ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3037/.

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3

DELL'ANNO, MATTEO. « FUNCTIONAL FEED ADDITIVES FOR ANIMAL HEALTH ». Doctoral thesis, Università degli Studi di Milano, 2023. https://hdl.handle.net/2434/955511.

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World population growth is leading to an increase of the of food from animal origin demand. For the future of the planet and food-production system sustainability some important issues required to be faced. Antimicrobial resistance is one of the most important global concerns cause of thousands of deaths per year and livestock can contribute to the antimicrobial resistance spreading. In livestock, the highest use of antibiotic treatments is recorded in young animals, due to their immature immune system, and the presence of several stress sources that predispose young animals to develop multifactorial diseases, particularly from gastrointestinal origin, that causes important economic losses and antibiotic use. Nutrition is no longer considered as science that only satisfies nutritional requirements but is considered fundamental for its functionality through the supplementation of ingredients and additives which contain bioactive molecules that positively impact on health. Functional feed ingredients and additives possess bioactive characteristics, such as antibacterial and antioxidant activities, capable of contrasting infections and improving animal health or a particular organic function. Preserving intestinal health decreases the incidence of pathologies, optimises digestive processes, and promotes animal performance thus resulting in higher profitability for the farmers. The aim of the following project was to evaluate innovative functional feed additives for animal nutrition, in order to increase animal health, performance and reduce the use of antibiotics in farm animals. The attention was focused on the evaluation of algae, tannins extract, leonardite, tributyrin and probiotics as functional feed additives alternative to antibiotics. For reaching this goal different in vitro, in vivo and ex vivo approaches have been used. In vitro methods allowed to characterize functional feed additives for their antimicrobial and antioxidants effects and cell culture was useful to predict their interaction with the intestinal epithelium. In vivo zootechnical trials were conducted on young animals to assess dietary supplementation of functional additives on growth performance, prevention of gastroenteric disorders, metabolic status and microbiota modulation. Obtained results highlighted that functional additives were characterized by bioactive properties such as antioxidant and antimicrobial effects. Their supplementation showed a plethora of positive impacts including higher zootechnical performance, decreased diarrhoea occurrence, improved health status and microbiota modulation. A combined effect was also assessed in order to evaluate a possible synergistic of different additives. The combination resulted in a positive effect for diarrhoea prevention with a slight modulation for the gut microbial environment. Even if feed additives displayed different bioactivities in vitro, they did not always reveal a boosting effect on growth performance in vivo resulting less evident for farmer perception. However, the reduction of gastrointestinal disorders incidence could be considered the most interesting characteristic of functional feed additives which have shown to possibly reduce pathologies occurrence thus improving farm profitability. Lastly, due to the needing to decrease animal for experimental purposes an innovative ex vivo intestinal perfusion model was developed in order to study nutrient bioaccessibility for obtaining reliable science-based data in line with the 3R principles. In conclusion, tested compounds can not substitute the therapeutic treatment of antibiotics. However, the utilization dietary approaches supplementing functional feed additives can significantly contribute for decreasing pathology occurrence, boosting animal health and performance thus the antibiotics use. In line with the One Health principles, antibiotics reduction is a key point for the future sustainable development on the planet. The use of functional feed additives can be considered as interesting alternative to antibiotics due to their ability to prevent multifactorial disorders and thus reducing the antibiotic treatments in livestock farming.

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4

Brogna, Nico <1973&gt. « Miglioramento della qualità della carne suina : modificazioni della frazione lipidica nella filiera di produzione del suino pesante ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/223/1/TesiDottorato_Nico_Brogna.pdf.

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5

Brogna, Nico <1973&gt. « Miglioramento della qualità della carne suina : modificazioni della frazione lipidica nella filiera di produzione del suino pesante ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/223/.

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6

Paganelli, Riccardo <1976&gt. « Micotossine e produzioni zootecniche : esperienze su galline ovaiole e suini ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/224/1/paganelli_tesi_dottorato.pdf.

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7

Paganelli, Riccardo <1976&gt. « Micotossine e produzioni zootecniche : esperienze su galline ovaiole e suini ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/224/.

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8

Grilli, Ester <1978&gt. « Development of non pharmaceutical strategies to improve intestinal health in weaning piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/442/1/TESI_DOTTORATO.pdf.

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9

Grilli, Ester <1978&gt. « Development of non pharmaceutical strategies to improve intestinal health in weaning piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2007. http://amsdottorato.unibo.it/442/.

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10

Cipollini, Irene <1976&gt. « Pet food : quality and quality improvement ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1058/1/Tesi_Cipollini_Irene.pdf.

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Today’s pet food industry is growing rapidly, with pet owners demanding high-quality diets for their pets. The primary role of diet is to provide enough nutrients to meet metabolic requirements, while giving the consumer a feeling of well-being. Diet nutrient composition and digestibility are of crucial importance for health and well being of animals. A recent strategy to improve the quality of food is the use of “nutraceuticals” or “Functional foods”. At the moment, probiotics and prebiotics are among the most studied and frequently used functional food compounds in pet foods. The present thesis reported results from three different studies. The first study aimed to develop a simple laboratory method to predict pet foods digestibility. The developed method was based on the two-step multi-enzymatic incubation assay described by Vervaeke et al. (1989), with some modification in order to better represent the digestive physiology of dogs. A trial was then conducted to compare in vivo digestibility of pet-foods and in vitro digestibility using the newly developed method. Correlation coefficients showed a close correlation between digestibility data of total dry matter and crude protein obtained with in vivo and in vitro methods (0.9976 and 0.9957, respectively). Ether extract presented a lower correlation coefficient, although close to 1 (0.9098). Based on the present results, the new method could be considered as an alternative system of evaluation of dog foods digestibility, reducing the need for using experimental animals in digestibility trials. The second parte of the study aimed to isolate from dog faeces a Lactobacillus strain capable of exert a probiotic effect on dog intestinal microflora. A L. animalis strain was isolated from the faeces of 17 adult healthy dogs..The isolated strain was first studied in vitro when it was added to a canine faecal inoculum (at a final concentration of 6 Log CFU/mL) that was incubated in anaerobic serum bottles and syringes which simulated the large intestine of dogs. Samples of fermentation fluid were collected at 0, 4, 8, and 24 hours for analysis (ammonia, SCFA, pH, lactobacilli, enterococci, coliforms, clostridia). Consequently, the L. animalis strain was fed to nine dogs having lactobacilli counts lower than 4.5 Log CFU per g of faeces. The study indicated that the L animalis strain was able to survive gastrointestinal passage and transitorily colonize the dog intestine. Both in vitro and in vivo results showed that the L. animalis strain positively influenced composition and metabolism of the intestinal microflora of dogs. The third trail investigated in vitro the effects of several non-digestible oligosaccharides (NDO) on dog intestinal microflora composition and metabolism. Substrates were fermented using a canine faecal inoculum that was incubated in anaerobic serum bottles and syringes. Substrates were added at the final concentration of 1g/L (inulin, FOS, pectin, lactitol, gluconic acid) or 4g/L (chicory). Samples of fermentation fluid were collected at 0, 6, and 24 hours for analysis (ammonia, SCFA, pH, lactobacilli, enterococci, coliforms). Gas production was measured throughout the 24 h of the study. Among the tested NDO lactitol showed the best prebiotic properties. In fact, it reduced coliforms and increased lactobacilli counts, enhanced microbial fermentation and promoted the production of SCFA while decreasing BCFA. All the substrates that were investigated showed one or more positive effects on dog faecal microflora metabolism or composition. Further studies (in particular in vivo studies with dogs) will be needed to confirm the prebiotic properties of lactitol and evaluate its optimal level of inclusion in the diet.

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11

Cipollini, Irene <1976&gt. « Pet food : quality and quality improvement ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1058/.

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Today’s pet food industry is growing rapidly, with pet owners demanding high-quality diets for their pets. The primary role of diet is to provide enough nutrients to meet metabolic requirements, while giving the consumer a feeling of well-being. Diet nutrient composition and digestibility are of crucial importance for health and well being of animals. A recent strategy to improve the quality of food is the use of “nutraceuticals” or “Functional foods”. At the moment, probiotics and prebiotics are among the most studied and frequently used functional food compounds in pet foods. The present thesis reported results from three different studies. The first study aimed to develop a simple laboratory method to predict pet foods digestibility. The developed method was based on the two-step multi-enzymatic incubation assay described by Vervaeke et al. (1989), with some modification in order to better represent the digestive physiology of dogs. A trial was then conducted to compare in vivo digestibility of pet-foods and in vitro digestibility using the newly developed method. Correlation coefficients showed a close correlation between digestibility data of total dry matter and crude protein obtained with in vivo and in vitro methods (0.9976 and 0.9957, respectively). Ether extract presented a lower correlation coefficient, although close to 1 (0.9098). Based on the present results, the new method could be considered as an alternative system of evaluation of dog foods digestibility, reducing the need for using experimental animals in digestibility trials. The second parte of the study aimed to isolate from dog faeces a Lactobacillus strain capable of exert a probiotic effect on dog intestinal microflora. A L. animalis strain was isolated from the faeces of 17 adult healthy dogs..The isolated strain was first studied in vitro when it was added to a canine faecal inoculum (at a final concentration of 6 Log CFU/mL) that was incubated in anaerobic serum bottles and syringes which simulated the large intestine of dogs. Samples of fermentation fluid were collected at 0, 4, 8, and 24 hours for analysis (ammonia, SCFA, pH, lactobacilli, enterococci, coliforms, clostridia). Consequently, the L. animalis strain was fed to nine dogs having lactobacilli counts lower than 4.5 Log CFU per g of faeces. The study indicated that the L animalis strain was able to survive gastrointestinal passage and transitorily colonize the dog intestine. Both in vitro and in vivo results showed that the L. animalis strain positively influenced composition and metabolism of the intestinal microflora of dogs. The third trail investigated in vitro the effects of several non-digestible oligosaccharides (NDO) on dog intestinal microflora composition and metabolism. Substrates were fermented using a canine faecal inoculum that was incubated in anaerobic serum bottles and syringes. Substrates were added at the final concentration of 1g/L (inulin, FOS, pectin, lactitol, gluconic acid) or 4g/L (chicory). Samples of fermentation fluid were collected at 0, 6, and 24 hours for analysis (ammonia, SCFA, pH, lactobacilli, enterococci, coliforms). Gas production was measured throughout the 24 h of the study. Among the tested NDO lactitol showed the best prebiotic properties. In fact, it reduced coliforms and increased lactobacilli counts, enhanced microbial fermentation and promoted the production of SCFA while decreasing BCFA. All the substrates that were investigated showed one or more positive effects on dog faecal microflora metabolism or composition. Further studies (in particular in vivo studies with dogs) will be needed to confirm the prebiotic properties of lactitol and evaluate its optimal level of inclusion in the diet.

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12

Pizzamiglio, Valentina <1979&gt. « Nutritional strategies to control mycotoxin damages in swine ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1061/1/Tesi_Pizzamiglio_Valentina.pdf.

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Mycotoxins are contaminants of agricultural products both in the field and during storage and can enter the food chain through contaminated cereals and foods (milk, meat, and eggs) obtained from animals fed mycotoxin contaminated feeds. Mycotoxins are genotoxic carcinogens that cause health and economic problems. Ochratoxin A and fumonisin B1 have been classified by the International Agency for Research on Cancer in 1993, as “possibly carcinogenic to humans” (class 2B). To control mycotoxins induced damages, different strategies have been developed to reduce the growth of mycotoxigenic fungi as well as to decontaminate and/or detoxify mycotoxin contaminated foods and animal feeds. Critical points, target for these strategies, are: prevention of mycotoxin contamination, detoxification of mycotoxins already present in food and feed, inhibition of mycotoxin absorption in the gastrointestinal tract, reduce mycotoxin induced damages when absorption occurs. Decontamination processes, as indicate by FAO, needs the following requisites to reduce toxic and economic impact of mycotoxins: it must destroy, inactivate, or remove mycotoxins; it must not produce or leave toxic and/or carcinogenic/mutagenic residues in the final products or in food products obtained from animals fed decontaminated feed; it must be capable of destroying fungal spores and mycelium in order to avoiding mycotoxin formation under favorable conditions; it should not adversely affect desirable physical and sensory properties of the feedstuff; it has to be technically and economically feasible. One important approach to the prevention of mycotoxicosis in livestock is the addition in the diets of the non-nutritionally adsorbents that bind mycotoxins preventing the absorption in the gastrointestinal tract. Activated carbons, hydrated sodium calcium aluminosilicate (HSCAS), zeolites, bentonites, and certain clays, are the most studied adsorbent and they possess a high affinity for mycotoxins. In recent years, there has been increasing interest on the hypothesis that the absorption in consumed food can be inhibited by microorganisms in the gastrointestinal tract. Numerous investigators showed that some dairy strains of LAB and bifidobacteria were able to bind aflatoxins effectively. There is a strong need for prevention of the mycotoxin-induced damages once the toxin is ingested. Nutritional approaches, such as supplementation of nutrients, food components, or additives with protective effects against mycotoxin toxicity are assuming increasing interest. Since mycotoxins have been known to produce damages by increasing oxidative stress, the protective properties of antioxidant substances have been extensively investigated. Purpose of the present study was to investigate in vitro and in vivo, strategies to counteract mycotoxin threat particularly in swine husbandry. The Ussing chambers technique was applied in the present study that for the first time to investigate in vitro the permeability of OTA and FB1 through rat intestinal mucosa. Results showed that OTA and FB1 were not absorbed from rat small intestine mucosa. Since in vivo absorption of both mycotoxins normally occurs, it is evident that in these experimental conditions Ussing diffusion chambers were not able to assess the intestinal permeability of OTA and FB1. A large number of LAB strains isolated from feces and different gastrointestinal tract regions of pigs and poultry were screened for their ability to remove OTA, FB1, and DON from bacterial medium. Results of this in vitro study showed low efficacy of isolated LAB strains to reduce OTA, FB1, and DON from bacterial medium. An in vivo trial in rats was performed to evaluate the effects of in-feed supplementation of a LAB strain, Pediococcus pentosaceus FBB61, to counteract the toxic effects induced by exposure to OTA contaminated diets. The study allows to conclude that feed supplementation with P. pentosaceus FBB61 ameliorates the oxidative status in liver, and lowers OTA induced oxidative damage in liver and kidney if diet was contaminated by OTA. This P. pentosaceus FBB61 feature joined to its bactericidal activity against Gram positive bacteria and its ability to modulate gut microflora balance in pigs, encourage additional in vivo experiments in order to better understand the potential role of P. pentosaceus FBB61 as probiotic for farm animals and humans. In the present study, in vivo trial on weaned piglets fed FB1 allow to conclude that feeding of 7.32 ppm of FB1 for 6 weeks did not impair growth performance. Deoxynivalenol contamination of feeds was evaluated in an in vivo trial on weaned piglets. The comparison between growth parameters of piglets fed DON contaminated diet and contaminated diet supplemented with the commercial product did not reach the significance level but piglet growth performances were numerically improved when the commercial product was added to DON contaminated diet. Further studies are needed to improve knowledge on mycotoxins intestinal absorption, mechanism for their detoxification in feeds and foods, and nutritional strategies to reduce mycotoxins induced damages in animals and humans. The multifactorial approach acting on each of the various steps could be a promising strategy to counteract mycotoxins damages.

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13

Pizzamiglio, Valentina <1979&gt. « Nutritional strategies to control mycotoxin damages in swine ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1061/.

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Mycotoxins are contaminants of agricultural products both in the field and during storage and can enter the food chain through contaminated cereals and foods (milk, meat, and eggs) obtained from animals fed mycotoxin contaminated feeds. Mycotoxins are genotoxic carcinogens that cause health and economic problems. Ochratoxin A and fumonisin B1 have been classified by the International Agency for Research on Cancer in 1993, as “possibly carcinogenic to humans” (class 2B). To control mycotoxins induced damages, different strategies have been developed to reduce the growth of mycotoxigenic fungi as well as to decontaminate and/or detoxify mycotoxin contaminated foods and animal feeds. Critical points, target for these strategies, are: prevention of mycotoxin contamination, detoxification of mycotoxins already present in food and feed, inhibition of mycotoxin absorption in the gastrointestinal tract, reduce mycotoxin induced damages when absorption occurs. Decontamination processes, as indicate by FAO, needs the following requisites to reduce toxic and economic impact of mycotoxins: it must destroy, inactivate, or remove mycotoxins; it must not produce or leave toxic and/or carcinogenic/mutagenic residues in the final products or in food products obtained from animals fed decontaminated feed; it must be capable of destroying fungal spores and mycelium in order to avoiding mycotoxin formation under favorable conditions; it should not adversely affect desirable physical and sensory properties of the feedstuff; it has to be technically and economically feasible. One important approach to the prevention of mycotoxicosis in livestock is the addition in the diets of the non-nutritionally adsorbents that bind mycotoxins preventing the absorption in the gastrointestinal tract. Activated carbons, hydrated sodium calcium aluminosilicate (HSCAS), zeolites, bentonites, and certain clays, are the most studied adsorbent and they possess a high affinity for mycotoxins. In recent years, there has been increasing interest on the hypothesis that the absorption in consumed food can be inhibited by microorganisms in the gastrointestinal tract. Numerous investigators showed that some dairy strains of LAB and bifidobacteria were able to bind aflatoxins effectively. There is a strong need for prevention of the mycotoxin-induced damages once the toxin is ingested. Nutritional approaches, such as supplementation of nutrients, food components, or additives with protective effects against mycotoxin toxicity are assuming increasing interest. Since mycotoxins have been known to produce damages by increasing oxidative stress, the protective properties of antioxidant substances have been extensively investigated. Purpose of the present study was to investigate in vitro and in vivo, strategies to counteract mycotoxin threat particularly in swine husbandry. The Ussing chambers technique was applied in the present study that for the first time to investigate in vitro the permeability of OTA and FB1 through rat intestinal mucosa. Results showed that OTA and FB1 were not absorbed from rat small intestine mucosa. Since in vivo absorption of both mycotoxins normally occurs, it is evident that in these experimental conditions Ussing diffusion chambers were not able to assess the intestinal permeability of OTA and FB1. A large number of LAB strains isolated from feces and different gastrointestinal tract regions of pigs and poultry were screened for their ability to remove OTA, FB1, and DON from bacterial medium. Results of this in vitro study showed low efficacy of isolated LAB strains to reduce OTA, FB1, and DON from bacterial medium. An in vivo trial in rats was performed to evaluate the effects of in-feed supplementation of a LAB strain, Pediococcus pentosaceus FBB61, to counteract the toxic effects induced by exposure to OTA contaminated diets. The study allows to conclude that feed supplementation with P. pentosaceus FBB61 ameliorates the oxidative status in liver, and lowers OTA induced oxidative damage in liver and kidney if diet was contaminated by OTA. This P. pentosaceus FBB61 feature joined to its bactericidal activity against Gram positive bacteria and its ability to modulate gut microflora balance in pigs, encourage additional in vivo experiments in order to better understand the potential role of P. pentosaceus FBB61 as probiotic for farm animals and humans. In the present study, in vivo trial on weaned piglets fed FB1 allow to conclude that feeding of 7.32 ppm of FB1 for 6 weeks did not impair growth performance. Deoxynivalenol contamination of feeds was evaluated in an in vivo trial on weaned piglets. The comparison between growth parameters of piglets fed DON contaminated diet and contaminated diet supplemented with the commercial product did not reach the significance level but piglet growth performances were numerically improved when the commercial product was added to DON contaminated diet. Further studies are needed to improve knowledge on mycotoxins intestinal absorption, mechanism for their detoxification in feeds and foods, and nutritional strategies to reduce mycotoxins induced damages in animals and humans. The multifactorial approach acting on each of the various steps could be a promising strategy to counteract mycotoxins damages.

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14

De, Filippi Sara <1977&gt. « Importanza dell'interazione tra la dieta, i microrganismi commensali e la microflora patogena, nel suino in svezzamento ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1089/1/Tesi_De_Filippi_Sara.pdf.

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De, Filippi Sara <1977&gt. « Importanza dell'interazione tra la dieta, i microrganismi commensali e la microflora patogena, nel suino in svezzamento ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2008. http://amsdottorato.unibo.it/1089/.

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16

Pastò, Luigina Fernanda <1974&gt. « Impiego di additivi "naturali" nell'alimentazione del bovino da carne ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2602/1/past%C3%B2_luiginafernanda_tesi.pdf.

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Pastò, Luigina Fernanda <1974&gt. « Impiego di additivi "naturali" nell'alimentazione del bovino da carne ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2602/.

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Canestrari, Giorgia <1980&gt. « Muffe e micotossine : indicatori di attività fungina ed effetti dell' ocratossina nella gallina ovaiola ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2605/1/giorgia_canestrari_muffe_e_micotossine_indicatori_di_attivit%C3%A0_fungina_ed_effetti_dell%27_ocratossina_nella_gallina_ovaiola.pdf.

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Canestrari, Giorgia <1980&gt. « Muffe e micotossine : indicatori di attività fungina ed effetti dell' ocratossina nella gallina ovaiola ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2605/.

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Palmonari, Alberto <1981&gt. « Fermentazioni ruminali e fattori che influenzano le proprietà nutritive dell'erba medica ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2715/1/Alberto_Palmonari_Tesi_dottorato.pdf.

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Palmonari, Alberto <1981&gt. « Fermentazioni ruminali e fattori che influenzano le proprietà nutritive dell'erba medica ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2715/.

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Fustini, Mattia <1982&gt. « Struttura della fibra, benessere delle bovine e risposte produttive ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2728/1/Mattia_Fustini_tesi_dottorato.pdf.

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Fustini, Mattia <1982&gt. « Struttura della fibra, benessere delle bovine e risposte produttive ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2728/.

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Burzo, Antonella <1978&gt. « La compatibilità ambientale nei Piani di Sviluppo Rurale : un modello di analisi per le regioni italiane ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2923/1/burzo_antonella_tesi.pdf.

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Burzo, Antonella <1978&gt. « La compatibilità ambientale nei Piani di Sviluppo Rurale : un modello di analisi per le regioni italiane ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/2923/.

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Messori, Stefano <1981&gt. « Dietary strategies to minimize the detrimental impact of weaning on gut morphology, physiology and microbiota of piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3382/1/Messori_Stefano_Tesi.pdf.

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Weaning is a crucial period in the management of piglets. In modern piggeries economic interest make weaning age decrease more and more and the detrimental consequences of weaning have as much importance as earlier the weaning occurs. The risk of development of post-weaning diarrhea (PWD) in piglets is high and PWD is the cause of serious economic losses in pig herds. In the past the supplementation of the feed given after weaning with growth promoters antibiotics, in order to keep PWD under control, used to be a common practice, but their usage has been banned in EU since 2006. This measure led to the investigation of alternative suitable feed supplements that would be reasonably efficient in protecting and sustaining animal health and performance. Aim of this thesis was to evaluate the effect of some different alternatives to growth-promoters antibiotics on weaning piglets and to assess if some of them could be considered as valuables options to replace auxinic in animal feeding. The study is composed by four experimental trials. The first one aims to identify mechanisms involved in the auxinic effects of antibiotics in the diets; the following three evaluate the addition butyric acid, tryptophan, and nitrate as alternative to in-feed antimicrobials. Although some results are controversial, it appears from the data presented that the alternatives to in-feed antibiotics considered may exert positive effects on some zootechnical and health parameters on piglet in the post-weaning period. Anyway, the mechanism of action and the interaction with microbiota of such additives should be investigated inside out because many effects remains poorly understood.

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27

Messori, Stefano <1981&gt. « Dietary strategies to minimize the detrimental impact of weaning on gut morphology, physiology and microbiota of piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3382/.

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Weaning is a crucial period in the management of piglets. In modern piggeries economic interest make weaning age decrease more and more and the detrimental consequences of weaning have as much importance as earlier the weaning occurs. The risk of development of post-weaning diarrhea (PWD) in piglets is high and PWD is the cause of serious economic losses in pig herds. In the past the supplementation of the feed given after weaning with growth promoters antibiotics, in order to keep PWD under control, used to be a common practice, but their usage has been banned in EU since 2006. This measure led to the investigation of alternative suitable feed supplements that would be reasonably efficient in protecting and sustaining animal health and performance. Aim of this thesis was to evaluate the effect of some different alternatives to growth-promoters antibiotics on weaning piglets and to assess if some of them could be considered as valuables options to replace auxinic in animal feeding. The study is composed by four experimental trials. The first one aims to identify mechanisms involved in the auxinic effects of antibiotics in the diets; the following three evaluate the addition butyric acid, tryptophan, and nitrate as alternative to in-feed antimicrobials. Although some results are controversial, it appears from the data presented that the alternatives to in-feed antibiotics considered may exert positive effects on some zootechnical and health parameters on piglet in the post-weaning period. Anyway, the mechanism of action and the interaction with microbiota of such additives should be investigated inside out because many effects remains poorly understood.

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Grandi, Monica <1982&gt. « Il petfood nella realtà attuale : ricerche su aspetti qualitativi e nutro-funzionali degli alimenti per cani e gatti ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3519/1/Grandi_Monica_tesi.pdf.

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Grandi, Monica <1982&gt. « Il petfood nella realtà attuale : ricerche su aspetti qualitativi e nutro-funzionali degli alimenti per cani e gatti ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3519/.

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30

Priori, Davide <1976&gt. « Diet Effects on Activation and Maturation of Feed Control over the Gastrointestinal Defence Barrier in Piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4764/1/Priori_Davide_tesi.pdf.

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Weaning is an important and complex step involving many stresses that interfere deeply with feed intake, gastro-intestinal tract (GIT) development and adaptation to the weaning diet in young pigs. The health of the pig at weaning, its nutrition in the immediate post-weaning period, and the physical, microbiological and psychological environment are all factors that interact to determine food intake and subsequent growth. GIT disorders, infections and diarrhoea increase at the time of weaning, in fact pathogens such as enterotoxigenic Escherichia coli (ETEC) are major causes of mucosal damage in post-weaning disease contributing to diarrhoea in suckling and post-weaned pigs. The European ban in 2006 put on antibiotic growth promoters (AGP) has stimulated research on the mechanisms of GIT disorders and on nutritional approaches for preventing or reducing such disturbances avoiding AGPs. Concerning these aspects here are presented five studies based on the interplay among nutrition, genomic, immunity and physiology with the aim to clarify some of these problematic issues around weaning period in piglets. The first three evaluate the effects of diets threonine or tryptophan enriched on gut defence and health as possible alternatives to AGP in the gut. The fourth is focused on the possible immunological function related with the development of the stomach. The fifth is a pilot study on the gastric sensing and orexygenic signal given by fasting or re-feeding conditions. Although some results are controversial, it appears that both tryptophan and threonine supplementation in weaning diets have a preventive role in E.coli PWD and favorable effects in the gut especially in relation to ETEC susceptible genotype. While the stomach is believed as almost aseptic organ, it shows an immune activity related with the mucosal maturation. Moreover it shows an orexygenic role of both oxyntic mucosa and pyloric mucosa, and its possible relation with nutrient sensing stimuli.

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Priori, Davide <1976&gt. « Diet Effects on Activation and Maturation of Feed Control over the Gastrointestinal Defence Barrier in Piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4764/.

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Weaning is an important and complex step involving many stresses that interfere deeply with feed intake, gastro-intestinal tract (GIT) development and adaptation to the weaning diet in young pigs. The health of the pig at weaning, its nutrition in the immediate post-weaning period, and the physical, microbiological and psychological environment are all factors that interact to determine food intake and subsequent growth. GIT disorders, infections and diarrhoea increase at the time of weaning, in fact pathogens such as enterotoxigenic Escherichia coli (ETEC) are major causes of mucosal damage in post-weaning disease contributing to diarrhoea in suckling and post-weaned pigs. The European ban in 2006 put on antibiotic growth promoters (AGP) has stimulated research on the mechanisms of GIT disorders and on nutritional approaches for preventing or reducing such disturbances avoiding AGPs. Concerning these aspects here are presented five studies based on the interplay among nutrition, genomic, immunity and physiology with the aim to clarify some of these problematic issues around weaning period in piglets. The first three evaluate the effects of diets threonine or tryptophan enriched on gut defence and health as possible alternatives to AGP in the gut. The fourth is focused on the possible immunological function related with the development of the stomach. The fifth is a pilot study on the gastric sensing and orexygenic signal given by fasting or re-feeding conditions. Although some results are controversial, it appears that both tryptophan and threonine supplementation in weaning diets have a preventive role in E.coli PWD and favorable effects in the gut especially in relation to ETEC susceptible genotype. While the stomach is believed as almost aseptic organ, it shows an immune activity related with the mucosal maturation. Moreover it shows an orexygenic role of both oxyntic mucosa and pyloric mucosa, and its possible relation with nutrient sensing stimuli.

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Panciroli, Nicola <1982&gt. « Strategie alimentari atte a incrementare il contenuto di Omega3 e CLA del latte ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5842/1/Panciroli_Nicola_tesi.pdf.

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Tra i componenti naturali biologicamente attivi, e con cui è possibile arricchire il latte, notevole importanza rivestono gli acidi grassi Omega3 e i CLA. I ruoli benefici svolti da questi particolari lipidi si manifestano soprattutto nella regolazione dei processi infiammatori, nella prevenzione del diabete e delle malattie cardiovascolari; è inoltre dimostrato come i CLA abbiano attività anticancerogena e ipocolesterolemica, stimolino il sistema immunitario e prevengano l’insorgenza del diabete e delle malattie croniche non trasmissibili. Lo scopo di questo lavoro è stato quello di individuare, in condizioni sperimentali controllate e nelle comuni realtà di allevamento, le possibili strategie alimentari atte ad aumentare le concentrazioni di Omega-3 e CLA del latte vaccino, senza penalizzare i titoli di grasso del latte. I lavori sperimentali effettuati possono essere distinti in 3 fasi: una prima fase in cui l’oggetto principale delle ricerche svolte è stato l’incremento in acidi grassi Omega3 del latte, una seconda fase in cui l’obiettivo si è allargato anche all’incremento delle concentrazioni in CLA, e una terza fase che ha avuto come scopo quello di incrementare i livelli di Omega3 e CLA del latte senza penalizzare i titoli di grasso. Le strategie alimentari più efficaci si sono basate sulla modificazione degli apporti lipidici della razione attraverso la supplementazione con seme di soia o relativo olio, semi di lino o relativo olio, olii di pesce e acido stearico. Le ricerche svolte hanno evidenziato come, attraverso opportune ed accurate modulazioni degli apporti lipidici delle razioni, sia di fatto possibile innalzare i contenuti di acidi grassi della serie Omega3 e CLA nel latte vaccino, senza penalizzare i titoli del grasso del latte.
Omega3 and CLA are among the most important active biologic components usually used as milk-enricheners. The main beneficial roles accomplished by these particular lipids are: the regulation of inflammatory processes and the prevention of diabetes and cardiovascular diseases. Furthermore, it is proven the CLA anticancer and hypocholesterolemic effect. Aim of this study was to identify the feed strategies to increase the Omega-3 and CLA concentration in milk, without affecting the titles of milk fat. Tests were carried out under controlled experimental conditions and in accomplishment with the common farming reality. The research was divided in three phases. Main object of the first phase was to find the best strategies to increase Omega-3 fatty acids of milk. The second phase collected the tests in which the goal was extended to include the increase also in CLA concentrations. The third phase aimed to enrich the levels of Omega-3 and CLA in milk without affecting the fat titles of milk. The researches were mostly conducted at the didactic-experimental farm of Bologna University; other tests were directed also in commercial farms, in order to respect the common operating conditions. The most effective dietary strategies based on the modification of lipid dietary intake. Supplementation of the ration was mainly based on soybean and relative oil, linseed and relative oil, fish oils and stearic acid. Results from this research show that operating an appropriate and accurate modulation of lipid intake of rations allows to raise the content of fatty acids Omega-3 and CLA in cow's milk, without penalizing the titles of milk fat.

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Panciroli, Nicola <1982&gt. « Strategie alimentari atte a incrementare il contenuto di Omega3 e CLA del latte ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5842/.

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Résumé :

Tra i componenti naturali biologicamente attivi, e con cui è possibile arricchire il latte, notevole importanza rivestono gli acidi grassi Omega3 e i CLA. I ruoli benefici svolti da questi particolari lipidi si manifestano soprattutto nella regolazione dei processi infiammatori, nella prevenzione del diabete e delle malattie cardiovascolari; è inoltre dimostrato come i CLA abbiano attività anticancerogena e ipocolesterolemica, stimolino il sistema immunitario e prevengano l’insorgenza del diabete e delle malattie croniche non trasmissibili. Lo scopo di questo lavoro è stato quello di individuare, in condizioni sperimentali controllate e nelle comuni realtà di allevamento, le possibili strategie alimentari atte ad aumentare le concentrazioni di Omega-3 e CLA del latte vaccino, senza penalizzare i titoli di grasso del latte. I lavori sperimentali effettuati possono essere distinti in 3 fasi: una prima fase in cui l’oggetto principale delle ricerche svolte è stato l’incremento in acidi grassi Omega3 del latte, una seconda fase in cui l’obiettivo si è allargato anche all’incremento delle concentrazioni in CLA, e una terza fase che ha avuto come scopo quello di incrementare i livelli di Omega3 e CLA del latte senza penalizzare i titoli di grasso. Le strategie alimentari più efficaci si sono basate sulla modificazione degli apporti lipidici della razione attraverso la supplementazione con seme di soia o relativo olio, semi di lino o relativo olio, olii di pesce e acido stearico. Le ricerche svolte hanno evidenziato come, attraverso opportune ed accurate modulazioni degli apporti lipidici delle razioni, sia di fatto possibile innalzare i contenuti di acidi grassi della serie Omega3 e CLA nel latte vaccino, senza penalizzare i titoli del grasso del latte.
Omega3 and CLA are among the most important active biologic components usually used as milk-enricheners. The main beneficial roles accomplished by these particular lipids are: the regulation of inflammatory processes and the prevention of diabetes and cardiovascular diseases. Furthermore, it is proven the CLA anticancer and hypocholesterolemic effect. Aim of this study was to identify the feed strategies to increase the Omega-3 and CLA concentration in milk, without affecting the titles of milk fat. Tests were carried out under controlled experimental conditions and in accomplishment with the common farming reality. The research was divided in three phases. Main object of the first phase was to find the best strategies to increase Omega-3 fatty acids of milk. The second phase collected the tests in which the goal was extended to include the increase also in CLA concentrations. The third phase aimed to enrich the levels of Omega-3 and CLA in milk without affecting the fat titles of milk. The researches were mostly conducted at the didactic-experimental farm of Bologna University; other tests were directed also in commercial farms, in order to respect the common operating conditions. The most effective dietary strategies based on the modification of lipid dietary intake. Supplementation of the ration was mainly based on soybean and relative oil, linseed and relative oil, fish oils and stearic acid. Results from this research show that operating an appropriate and accurate modulation of lipid intake of rations allows to raise the content of fatty acids Omega-3 and CLA in cow's milk, without penalizing the titles of milk fat.

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Tugnoli, Benedetta <1986&gt. « Effects of different nutritional strategies on intestinal inflammation in pigs ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6415/1/tugnoli_benedetta_tesi.pdf.

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Intestinal health is essential for the health of the body since the gastro-intestinal mucosa is the main site of interaction with the external environment, as well as the major area colonized by the microbiota. Intestinal health relies on proper barrier function, epithelial integrity and related mechanisms of protection (mucous layer, tight junctions, immune and inflammatory system). In pigs, during the weaning transition, intestinal inflammation and barrier integrity play a crucial role in regulating intestinal health and, consequently, pig’s health, growth and productivity. The aim of the project was to assess the impact of different nutritional strategies on the intestinal health of weaning piglets with reference to the inflammatory status and epithelial integrity. Therefore, in vivo trials were conducted to test the in-feed supplementation with zinc, tributyrin, or organic acids and nature-identical compounds (NIC) to weaning piglets. All the dietary interventions positively impacted the intestinal inflammatory status and, as a consequence, improved epithelial integrity by modulating tight junctions proteins (zinc or tributyrin) or by enhancing barrier properties measured with Ussing chambers (organic acids and NIC). These findings highlight that intestinal inflammation and barrier function are strictly linked, and that the control of inflammation is essential for adequate barrier function. In addition, in zinc trial and organic acids and NIC trial, better intestinal health could successfully result in better growth performance, as aimed for pig production improvement. To conclude, this work shows that dietary supplementation with bio-active substances such as zinc, tributyrin or organic acids and NIC may improve intestinal health of weaning piglets modulating intestinal inflammatory stress and barrier integrity and allowing better piglet’s health, growth and productivity.

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Tugnoli, Benedetta <1986&gt. « Effects of different nutritional strategies on intestinal inflammation in pigs ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6415/.

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Résumé :

Intestinal health is essential for the health of the body since the gastro-intestinal mucosa is the main site of interaction with the external environment, as well as the major area colonized by the microbiota. Intestinal health relies on proper barrier function, epithelial integrity and related mechanisms of protection (mucous layer, tight junctions, immune and inflammatory system). In pigs, during the weaning transition, intestinal inflammation and barrier integrity play a crucial role in regulating intestinal health and, consequently, pig’s health, growth and productivity. The aim of the project was to assess the impact of different nutritional strategies on the intestinal health of weaning piglets with reference to the inflammatory status and epithelial integrity. Therefore, in vivo trials were conducted to test the in-feed supplementation with zinc, tributyrin, or organic acids and nature-identical compounds (NIC) to weaning piglets. All the dietary interventions positively impacted the intestinal inflammatory status and, as a consequence, improved epithelial integrity by modulating tight junctions proteins (zinc or tributyrin) or by enhancing barrier properties measured with Ussing chambers (organic acids and NIC). These findings highlight that intestinal inflammation and barrier function are strictly linked, and that the control of inflammation is essential for adequate barrier function. In addition, in zinc trial and organic acids and NIC trial, better intestinal health could successfully result in better growth performance, as aimed for pig production improvement. To conclude, this work shows that dietary supplementation with bio-active substances such as zinc, tributyrin or organic acids and NIC may improve intestinal health of weaning piglets modulating intestinal inflammatory stress and barrier integrity and allowing better piglet’s health, growth and productivity.

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Pinna, Carlo <1985&gt. « Strategie nutrizionali finalizzate alla modulazione del microbiota intestinale del cane e del gatto ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7084/1/pinna_carlo_tesi.pdf.

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Il microbiota intestinale riveste un ruolo importantissimo nell’influenzare la salute dell’ospite. È stato dimostrato come la composizione della dieta possa condizionare lo stato di benessere dell’animale, inducendo importanti cambiamenti tra le popolazioni batteriche che coabitano l’intestino; l’uso di prebiotici rappresenta una delle strategie maggiormente impiegate per modulare positivamente la composizione ed il metabolismo dell’ecosistema gastroenterico. Il presente progetto di dottorato si è proposto di indagare gli effetti sul microbiota intestinale del cane e del gatto di diete a diverso tenore proteico e contenenti proteine di diversa digeribilità in presenza o meno di sostanze prebiotiche. Inoltre, sono stati valutati gli effetti della presenza di un estratto di Yucca schidigera e di tannini sulla microflora intestinale del gatto. In ultima istanza, sono state valutate le conseguenze di dosi crescenti di lattosio sul benessere intestinale del cane. I risultati del presente studio hanno rilevato come le sostanze prebiotiche influiscono sulla composizione e sul metabolismo della microflora del cane e del gatto, e come l’impiego di diete ricche di proteine possa avere conseguenze negative sull’ambiente intestinale. Tuttavia, la presenza di oligosaccaridi non sembra contrastare gli effetti negativi che diete ad alto tenore proteico potrebbero avere sull’ecosistema intestinale dell’animale. Nella successiva prova è stato evidenziato come l’inclusione nella dieta di estratti di Yucca e tannini possa contribuire a mitigare l’emanazione di sostanze maleodoranti dalle deiezioni degli animali da compagnia. Nel corso dell’ultima prova, nonostante non siano state osservate differenze tra le popolazioni microbiche intestinali, la somministrazione di dosi crescenti di lattosio ha indotto una certa riduzione delle fermentazioni proteolitiche microbiche. Ulteriori studi sono necessari per stabilire in che misura la dieta e gli alimenti “funzionali” possano influire sul microbiota intestinale del cane e del gatto e come queste informazioni possono essere utilizzate per migliorare miratamente l’alimentazione e lo stato di salute degli animali da compagnia.
The microbiota of the large intestine plays a fundamental role in maintaining the state of health of the gastrointestinal tract and the host. Considerable evidence suggests that dietary macronutrients and prebiotic substances may affect microbial composition and activity. Knowledge about the modulation of canine and feline intestinal microbiota in response to macronutrients and prebiotic supplementation is limited. However, such information is necessary to investigate further the complex interplay between host and intestinal microbiota in response to changes of diet. The research for this PhD thesis focused upon the changes of the intestinal microbiota and bacterial metabolites of dogs and cats, in response to feeding diets differing in their protein content and digestibility, and containing or not a source of prebiotics. Additionally, the effects of tannins and Yucca schidigera extract on feline intestinal microbiota were evaluated. Furthermore, aim of the last trial was to evaluate the effect of increasing level of lactose on composition and metabolism of dog intestinal microbiota. The results from the present thesis show that different prebiotics exert different effects on the composition and activity of canine and feline intestinal microbiota and that high dietary protein levels can have negative effects on the animal intestinal environment. However, administration of oligosaccharides doesn’t seem to counteract the negative effects that can be observed when companion animals are fed high-protein diets. In the other study, Yucca extract and tannins does not affect feline fecal microbiota. Despite this, a reduction of odour components was observed due to fermentation of substrates. Finally, results from the final study showed no difference between treatments on canine microbial population. However, proteolytic compounds were decreased by lactose. Future studies must determine how diet composition and prebiotic supplementation affect the gut microbiota and how this information may be used to improve diets and the host’s health.

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Pinna, Carlo <1985&gt. « Strategie nutrizionali finalizzate alla modulazione del microbiota intestinale del cane e del gatto ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7084/.

Texte intégral

Résumé :

Il microbiota intestinale riveste un ruolo importantissimo nell’influenzare la salute dell’ospite. È stato dimostrato come la composizione della dieta possa condizionare lo stato di benessere dell’animale, inducendo importanti cambiamenti tra le popolazioni batteriche che coabitano l’intestino; l’uso di prebiotici rappresenta una delle strategie maggiormente impiegate per modulare positivamente la composizione ed il metabolismo dell’ecosistema gastroenterico. Il presente progetto di dottorato si è proposto di indagare gli effetti sul microbiota intestinale del cane e del gatto di diete a diverso tenore proteico e contenenti proteine di diversa digeribilità in presenza o meno di sostanze prebiotiche. Inoltre, sono stati valutati gli effetti della presenza di un estratto di Yucca schidigera e di tannini sulla microflora intestinale del gatto. In ultima istanza, sono state valutate le conseguenze di dosi crescenti di lattosio sul benessere intestinale del cane. I risultati del presente studio hanno rilevato come le sostanze prebiotiche influiscono sulla composizione e sul metabolismo della microflora del cane e del gatto, e come l’impiego di diete ricche di proteine possa avere conseguenze negative sull’ambiente intestinale. Tuttavia, la presenza di oligosaccaridi non sembra contrastare gli effetti negativi che diete ad alto tenore proteico potrebbero avere sull’ecosistema intestinale dell’animale. Nella successiva prova è stato evidenziato come l’inclusione nella dieta di estratti di Yucca e tannini possa contribuire a mitigare l’emanazione di sostanze maleodoranti dalle deiezioni degli animali da compagnia. Nel corso dell’ultima prova, nonostante non siano state osservate differenze tra le popolazioni microbiche intestinali, la somministrazione di dosi crescenti di lattosio ha indotto una certa riduzione delle fermentazioni proteolitiche microbiche. Ulteriori studi sono necessari per stabilire in che misura la dieta e gli alimenti “funzionali” possano influire sul microbiota intestinale del cane e del gatto e come queste informazioni possono essere utilizzate per migliorare miratamente l’alimentazione e lo stato di salute degli animali da compagnia.
The microbiota of the large intestine plays a fundamental role in maintaining the state of health of the gastrointestinal tract and the host. Considerable evidence suggests that dietary macronutrients and prebiotic substances may affect microbial composition and activity. Knowledge about the modulation of canine and feline intestinal microbiota in response to macronutrients and prebiotic supplementation is limited. However, such information is necessary to investigate further the complex interplay between host and intestinal microbiota in response to changes of diet. The research for this PhD thesis focused upon the changes of the intestinal microbiota and bacterial metabolites of dogs and cats, in response to feeding diets differing in their protein content and digestibility, and containing or not a source of prebiotics. Additionally, the effects of tannins and Yucca schidigera extract on feline intestinal microbiota were evaluated. Furthermore, aim of the last trial was to evaluate the effect of increasing level of lactose on composition and metabolism of dog intestinal microbiota. The results from the present thesis show that different prebiotics exert different effects on the composition and activity of canine and feline intestinal microbiota and that high dietary protein levels can have negative effects on the animal intestinal environment. However, administration of oligosaccharides doesn’t seem to counteract the negative effects that can be observed when companion animals are fed high-protein diets. In the other study, Yucca extract and tannins does not affect feline fecal microbiota. Despite this, a reduction of odour components was observed due to fermentation of substrates. Finally, results from the final study showed no difference between treatments on canine microbial population. However, proteolytic compounds were decreased by lactose. Future studies must determine how diet composition and prebiotic supplementation affect the gut microbiota and how this information may be used to improve diets and the host’s health.

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Colombo, Michela <1977&gt. « Relevance of the pig stomach for the detection of dietary factors and gut maturation and control ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7190/1/Colombo_Michela_tesi.pdf.

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In this thesis two approaches were applied to achieve a double general objective. The first chapter was dedicated to the study of the distribution of the expression of genes of several bitter and fat receptor in several gastrointestinal tracts. A set of 7 genes for bitter taste and for 3 genes for fat taste was amplified with real-time PCR from mRNA extracted from 5 gastrointestinal segments of weaned pigs. The presence of gene expression for several chemosensing receptors for bitter and fat taste in different compartments of the stomach confirms that this organ should be considered a player for the early detection of bolus composition. In the second chapter we investigated in young pigs the distribution of butyrate-sensing olfactory receptor (OR51E1) receptor along the GIT, its relation with some endocrine markers, its variation with age, and after interventions affecting the gut environment and intestinal microbiota in piglets and in different tissues. Our results indicate that OR51E1 is strictly related to the normal GIT enteroendocrine activity. In the third chapter we investigated the differential gene expression between oxyntic and pyloric mucosa in seven starter pigs. The obtained data indicate that there is significant differential gene exression between oxintic of the young pig and pyloric mucosa and further functional studies are needed to confirm their physiological importance. In the last chapter, thymol, that has been proposed as an oral alternative to antibiotics in the feed of pigs and broilers, was introduced directly into the stomach of 8 weaned pigs and sampled for gastric oxyntic and pyloric mucosa. The analysis of the whole transcript expression shoes that the stimulation of gastric proliferative activity and the control of digestive activity by thymol can influence positively gastric maturation and function in the weaned pigs.

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Colombo, Michela <1977&gt. « Relevance of the pig stomach for the detection of dietary factors and gut maturation and control ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7190/.

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Résumé :

In this thesis two approaches were applied to achieve a double general objective. The first chapter was dedicated to the study of the distribution of the expression of genes of several bitter and fat receptor in several gastrointestinal tracts. A set of 7 genes for bitter taste and for 3 genes for fat taste was amplified with real-time PCR from mRNA extracted from 5 gastrointestinal segments of weaned pigs. The presence of gene expression for several chemosensing receptors for bitter and fat taste in different compartments of the stomach confirms that this organ should be considered a player for the early detection of bolus composition. In the second chapter we investigated in young pigs the distribution of butyrate-sensing olfactory receptor (OR51E1) receptor along the GIT, its relation with some endocrine markers, its variation with age, and after interventions affecting the gut environment and intestinal microbiota in piglets and in different tissues. Our results indicate that OR51E1 is strictly related to the normal GIT enteroendocrine activity. In the third chapter we investigated the differential gene expression between oxyntic and pyloric mucosa in seven starter pigs. The obtained data indicate that there is significant differential gene exression between oxintic of the young pig and pyloric mucosa and further functional studies are needed to confirm their physiological importance. In the last chapter, thymol, that has been proposed as an oral alternative to antibiotics in the feed of pigs and broilers, was introduced directly into the stomach of 8 weaned pigs and sampled for gastric oxyntic and pyloric mucosa. The analysis of the whole transcript expression shoes that the stimulation of gastric proliferative activity and the control of digestive activity by thymol can influence positively gastric maturation and function in the weaned pigs.

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Bonfante, Elena <1988&gt. « Studio dei fattori che influenzano la digeribilità della fibra nella bovina da latte : approcci dinamici ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amsdottorato.unibo.it/8183/1/Bonfante_Elena_Tesi.pdf.

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I ruminanti sono altamente specializzati nella digestione della fibra. In condizioni di ottima funzionalità digestiva, sono le particelle di foraggio ad essere trattenute per lungo tempo nel rumine dove possono essere degradate dai batteri cellulosolitici. Nonostante queste conoscenze, la stima della degradabilità ruminale delle porzioni potenzialmente degradabili delle fibre è stata notevolmente sottostimata da taluni modelli dinamici di razionamento. Studi più recenti realizzati da Krizsan, Ahvenjarvi e Huhtanen, hanno sostanzialmente rivisto gli assunti relativi alle percentuali di fibra digerita nel rumine. Le tecniche di valutazione in vivo della digeribilità della pdNDF utilizzando come marker l’uNDF240 hanno consentito di valutare in campo questo parametro. Gli studi fatti si sono proposti di valutare come la digeribilità della fibra della razione potesse essere modificata in funzione di una diversa granulometria della dieta e di diversi tassi di degradazione oraria (kd, %/h) di foraggi di medica. I risultati hanno evidenziato che: -l’utilizzo di razioni ricche di foraggi a granulometria ridotta non compromette lo stato di salute delle manze e consente comunque che la pdNDF sia ampiamente digerita; ciò avvalora l’ipotesi che la granulometria dei foraggi giustifica solo in parte la capacità di ritenzione selettiva del rumine che è legata anche ad altri fattori (peso specifico e capacità di galleggiamento); - nelle bovine in lattazione l’utilizzo di foraggi con un contenuto di fibra rapidamente degradabile e meno ricchi di uNDF consente di esaltare l’ingestione di sostanza secca oltre che la produzione di latte; la digeribilità complessiva della fibra non è invece sostanzialmente mutata in funzione del parametro “costante di degradabilità oraria” della pdNDF del foraggio; ancora una volta il risultato può essere spiegato alla luce della grande capacità di ritenzione selettiva del rumine nei confronti della fibra; - le equazioni proposte dal sistema di razionamento NorFor appaiono più adeguate nel predire la digeribilità della fibra.
It has been known that ruminants are highly specialized in fiber degradation. In normal conditions, the forage particles are the ones that are retained, more than others, for a long time in the rumen to be digested by the bacteria. However the prediction of the rumen digestibility of potentially digestible fiber has been underestimate in some models. More recent studies made by Krizsan, Ahvenjarvi e Huhtanen, have modified the values related to fiber digestibility in the rumen. The introduction of uNDF240 as internal marker to evaluate the pdNDF digestibility, allowed studying the digestibility in the field. The studies conducted in this thesis had the aim to evaluate the factors that can affect digestibility of the diet such as fiber particle size and the use of forages with different digestibility (kd, %/h). The results of this thesis showed that the reduction in fiber particle size increase the DMI without affect rumen health of growing heifers. Diet with short fiber particle size reached high level of digestion; this evaluation confirms the hypothesis that forage particle size is only one of the factor affecting the retention time in the rumen, and that other factors like particle density and buoyancy can be involved. In lactating cows the inclusion of highly digestible fiber and low in uNDF allows to increase the intake and performances; however the total digestibility didn’t change significantly. Again, these results can be justified by the different retention time in the rumen that can compensate the slow digestibility of some forage. Evaluating the pdNDF digestibility observed in this research with the models available, NorFor equations appears to predict the fiber behavior in the rumen.

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Vecchiato, Carla Giuditta <1989&gt. « Saccharomyces boulardii e prebiotici : effetti sul benessere intestinale del cane adulto ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8513/1/Tesi%20di%20dottorato_VecchiatoCG.pdf.

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La presente tesi di dottorato si è proposta di indagare gli effetti sul microbiota intestinale del cane di diverse sostanze ad azione prebiotica, da sole o in associazione ad un ceppo di Saccharomyces boulardii. In particolare, in un primo studio, si è voluto valutare in vitro gli effetti di un ceppo di S. boulardii (SB) impiegato singolarmente o in associazione con frutto-oligosaccaridi (SB), o con lattitolo (LAC). Sono stati previsti 6 trattamenti: 1) dieta di controllo (CTRL) senza aggiunta di substrati sperimentali; 2) SB; 3) FOS; 4) LAC; 5) SB+FOS; 6) SB+LAC. I risultati ottenuti nel presente esperimento in vitro potrebbero suggerire che S. boulardii non abbia agito come probiotico, mentre i prebiotici hanno indotto variazioni positive nella composizione e nel metabolismo del microbiota fecale canino. Il secondo studio ha visto l'impiego di un modello in vitro e di uno in vivo, dove sono stati testati gli effetti sulla salute intestinale del cane di alcuni supplementi nutrizionali: mannano-oligosaccaridi (MOS), prodotti a base di parete cellulare di lievito (MOS e CW), un ceppo di Saccharomyces boulardii (SB) e, solo in vitro, frutto-oligosaccaridi (FOS), da soli e in associazione a SB. il trial in vitro ha previsto 6 trattamenti: 1) dieta di CTRL; 2) MOS; 3) CW; 4) FOS; 5) SB; 6) CW + FOS; per la prova in vivo 16 cani (8 CTRL; 8 trattati) hanno testato MOS, CW, SB dopo un periodo iniziale di adattamento alla dieta, con 3 fasi: 1) CTRL vs. MOS; 2) CTRL vs. CW; 3) CTRL vs SB, intervallate da un periodo di dieta di base. I risultati ottenuti dal modello in vitro sono contrastanti: i trattamenti hanno sia stimolato l'attività del microbiota fecale, sia hanno manifestato un'azione inibitoria. dalla prova in vivo, i supplementi non sembrano aver sortito effetti particolari sulla composizione del microbiota fecale.
Aim of the present project was the evaluation of the effects of different prebiotics and yeast strains of Saccharomyces boulardii on the intestinal ecosystem of dogs, by use of microbial and chemical analyses. In the first part of the project, the effect of S.boulardii (SB), fructo-oligosaccharides (FOS), lactitol (LAC), and their combination were evaluated. There were 6 treatments: 1) control diet with no addition of substrates; 2) SB; 3) FOS; 4) LAC; 5) SB+FOS; 6) SB+LAC. In this study, SB failed to exert any effects on the selected bacterial populations. Conversely, administration of FOS and LAC may improve canine intestinal health, reducing proteolysis and enhancing VFA production. In the second part of the project (in vitro + in vivo trial), the effects of two yeast cell wall products (MOS and CW), a yeast strain of Saccharomyces boulardii (SB) and, only in vitro, fructo- oligosaccharides (FOS) were evaluated; the in vitro trial focused on 6 treatments: 1) control diet with no addition of substrates (CTRL); 2) MOS; 3) CW; 4) FOS; 5) SB; 6) CW + FOS. the in vivo feeding trial was conducted with 16 healthy adult dogs and 3 supplements were studied: 1) MOS; 2) CW; 3) SB. This was the experimental design: 1) 28d of adaptation to the base diet; 2) 28d of treatment with 2 groups (CTRL vs. MOS); 3) 28d of treatment with 2 groups (CTRL vs. CW); 3) 28d of treatment with 2 groups (CTRL vs. SB). After each experimental phase, a 14d wash out- period was conducted with the CTRL diet. Results from the in vitro study seem to show that supplements had both inhibitory and stimulating effects on faecal bacterial populations. Results from the in vivo study failed to highlight strong effects of the tested supplements on canine intestinal microbiota.

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Motta, Vincenzo <1983&gt. « Analysis of factors affecting the bacterial community variations in the gastrointestinal tract of pigs ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8656/1/Tesi_VM_Finale.pdf.

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The gut microbiota plays a fundamental role in the state of health, the performances and the welfare of the host. Different variables can affect the composition of the gut bacterial communities influencing the host-microbiota interplay. The aim of this thesis was to test the effect of some factors that could play a role in shaping the bacterial communities of the porcine gastrointestinal tract. In the first study, the microbiota profile from oxyntic mucosa, pyloric mucosa, gastric groove and luminal content of the stomach was analysed in weaned pigs, testing the hypothesis of the existence of multiple microbial niches in the gastric environment. A different pattern between mucosal and luminal bacterial communities was reported. In the second study, the effect of a long-term formic acid administration was tested on growth performances, on the H+/K+-ATPase presence in the oxyntic mucosa, on the expression of gene markers for inflammatory response in jejunal mucosa, and on jejunal bacterial community structure, in weaners piglets. The overall results suggested an adaptive response to the formic acid administration, and the bacterial community showed a reduction in lactic and butyric acid producing bacteria. In the third study, the piglet’s faecal microbiota rearrangement during the weaning transition was analysed taking into account the potential impact of the host A0 blood group. The weaning shift in bacterial community suggested a role of milk-derived lipids in microbiota shaping, while no effects related to the blood group were reported. These studies contributed to the knowledge on bacterial community shaping in young pigs, focusing the attention on aspects not yet well explored for the porcine gastrointestinal microbiota, such as the role of the gastric environment and of the blood group, and showing the effects of potential adaptation to treatments currently used in the swine industry such as the administration of the organic acids.

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Mammi, Ludovica Maria Eugenia <1985&gt. « Strategies to improve transition dairy cows health and milk quality ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amsdottorato.unibo.it/8705/1/Mammi_Ludovica_tesi.pdf.

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Despite numerous studies since decades, transition period of dairy cows remains a big issue for both researcher and farmers. The endocrine changes that characterize this period expose the animals to metabolic imbalance, immune depression and oxidative stress. This situation results in the emergence of metabolic and infectious disease in addition to reduced and impaired milk production, that finally lead to the 15% of culling occurring in the first weeks of lactation. Therefore, several strategies have been put in place in order to improve health and welfare of transition cows, taking into account environment, nutrition and management aspects. The main purpose of this work is to investigate through 3 studies the effects of some of these strategies. In the first study, the effects of overcrowding during dry period were evaluated on stress related blood markers, behavior and welfare of animals. Overcrowded cows showed higher blood level of dehydroepiandrosterone (DHEA) and cortisol than controls and a restlessness behavior. The second study aimed to investigate the impact of an immunomodulant feed supplement (Omnigen-AF) fed to 190 cows from dry off to 150 DIM, on their health and milk composition and quality. Supplemented cows, compared to controls, had lower incidence of postpartum disease and lower culling rate within 60 DIM. Milk production and quality was not influenced by the treatment except for a reduction of SCC among Holstein cows. The last study evaluated the consequences on quality of milk and Parmigiano Reggiano cheese of an antiketotic treatment (Kexxtone). Despite the great concern on this aspect among cheese producers, the treatment didn’t impaired nor milk nor cheese production, confirming the usefulness and safety of this treatment for the prevention of ketosis. Overall, this thesis confirms the need and the effectiveness of different strategies that aimed to improve transition dairy cows health and their milk production.

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Cavallini, Damiano <1992&gt. « Studio delle risposte comportamentali, produttive e sanitarie di bovine in lattazione esposte a diversi regimi dietetici ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amsdottorato.unibo.it/9247/1/Cavallini_Damiano_Tesi.pdf.

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L'unifeed a secco è il più diffuso nell'areale del Parmigiano Reggiano. In questa situazione, la peNDF deve essere ridotta per evitare selezione. Di conseguenza spesso presenta valori sotto la soglia minima. In più, spesso i fieni utilizzati sono di scarso valore nutritivo e si rendono necessari elevati livelli di concentrati nella razione. Tutto questo può portare alla diminuzione del tempo di ruminazione e produzione di saliva, aumentando il rischio di SARA. Dopo queste brevi premesse, due prove sono state effettuate presso la stalla sperimentale dell'università di Bologna. La prima con lo scopo di studiare il comportamento alimentare di vacche in lattazione sottoposte a regimi ad libitum/razionato con assenza/presenza di fieno lungo. La seconda si svolse con un improvviso cambio di stabulazione, dalla libera alla fissa, e quota di concentrati nell'unifeed. Da queste prove un grande mole di dati è stata registrata, grazie ai collari della ruminazione, boli reticolari e mangiatoie automatiche. I risultati ottenuti ci hanno permesso di confermare le interconnessioni tra comportamento alimentare, ruminazione e pH. Abbiamo anche verificato l'importanza di costanza di preparazione dell'unifeed e la grande capacità di adattamento delle bovine. Infatti la variabilità nelle gestione della mandria può provocare importanti sanitari. Quindi suggeriamo la supplementazione di fieno lungo in mangiatoia e lo sviluppo di tecnologia NIR in linea sul carro miscelatore. Infine sono state registrate importanti differenze individuali nel far fronte agli stati di stress alimentare. Uno studio più approfondito di questi aspetti sicuramente avrebbe risvolti positivi nella gestione della mandria e aprile la possibilità all'introduzione di nuovi indici di selezione.
TMR based on dry hay is the most common ration type on Parmigiano Reggiano area. In this situation, dietary particle size must be reduced in order to avoid sorting. Thus, peNDF values frequently are below the safety threshold. Moreover, hays commonly used are characterized by low quality and nutritional values, this fact leads to an increase in concentrates on the ration. All these evidences could lead to a decrease in rumination time and saliva production increases the risk of SARA. After these brief considerations, at the University of Bologna dairy experimental unit two trials were carried out. The first one had the aim to study eating behavior in dairy cows exposed to ad libitum or restricted TMR and presence/absence of long hay. The second one studied the abrupt change in housing, from free stall to tie stall, and TMR composition, with concentrate increasing. From these trials a huge flow of information was recorded, thanks to technologies devices such as rumination collars, reticular pH boluses and individual feed bunks. Obtained results permitted us to attest to the connections between eating behaviors and rumination time and pH. We verified how is important to keep constant of TMR preparation and the extreme capability of cow adaptation. In fact, the variability due to management errors could provoke important problems on the herd. Then, we suggest providing long hay in order to mitigate possible negatives effects and to develop on-line NIR systems to evaluate TMR production and consistency. Finally, we recorded important individual differences between cows, differences that could be magnified during stressing conditions and leading us to detect risky subjects. A deeper study of these characteristics could have an important practical reflect on daily herd management and open the possibility to include new selection indexes.

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Correa, Federico <1993&gt. « Feeding the Gut Microbiome and Immune Maturation to Manage Weaned Piglets ». Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amsdottorato.unibo.it/10111/1/PhD-Thesis%20Correa_final.pdf.

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This thesis reports five studies that may contribute to understand how weaning affects the immune and intestinal microbiota maturation of the piglet and proposes some possible nutritional strategies to attenuate its negative effects. The first study showed that weaning is associated in Payer’s patches with the activation of MHC response against class I antigens and that related to the stimulation to IFN-γ and showed, for the first time, that their blood at weaning remains dominated by immature blood cells. In the second study we tested if the use of a live vaccine against a conditionally but also genetically based intestinal disease, like PWD, could have an impact on the growth performance of pigs and their intestinal microbiota and if it could provide a model to test the response to nutritional strategies under conditions of an immune and intestinal stimulation for animals susceptible to ETEC type. In this study, we demonstrated how a vaccinal strain of F4/F18 E. coli can affect the gut microbial composition of piglets, regardless of their genetic susceptibility to ETEC infection. In the third study we evidenced how a nucleotide supplementation can favor the proliferation of jejunal Peyer patches and anticipate the maturation of the fecal microbiota. In the fourth study we reported how xylanase can favor the proliferation of Lactobacillus reuteri. Finally, we showed some first results on the muscles fiber development in fast- and slow-growing suckling pigs and the relationship with the intestinal microbiota. Taken together, the results presented in this thesis provide new insight about the interplay between the host-genetics, gut microbial composition, and host physiological status. Furthermore, it provides confirmation that the use of known genetic markers for ETEC F4 and F18 could represent a potential tool to stratify the animals in the trials both in healthy or challenge-based protocols.

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MARIANI, ELENA. « NUTRITION AS A TOOL TO MODULATE PRODUCTION ANIMAL HEALTH ». Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/626377.

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Nutrition plays an important role in maintaining a good health status of animals as nutrients can modulate oxidative status, immune and inflammatory response. Moreover, there is a need of innovative additives and feeds that can improve organism defences against diseases. The aim of this work was to monitor different markers of oxidative stress and inflammation in production animals in response to different feed additives. In this study, first, the activation of Nuclear factor-E2 related factor 2 in transgenic mice fed different sources and amount of fatty acids was monitored. Inducing the transcription of genes involved in oxidative stress response, Nrf2 represents one of the main actor in the organism defence against oxidative stress. In this phase, we used an innovative technique of in vivo imaging that allowed us to follow the experimental subject in time and in vivo. reducing significantly animal stress. Secondly, an evaluation of different oxidative and inflammatory markers was carried on post-weaning piglets fed with melon pulp concentrate. The double aim of this trial was to validate melon pulp concentrate as a feed additives to improve immune response in challenged pigs and to monitor the trends of commonly used markers during LPS challenge. Then, as the effectiveness of new feed additives are under investigation and their effect on intestinal health need to be demonstrated, is essential to turn attention to intestinal health biomarkers, non- or minimally invasive. For this reason, the main aim of the last study was to develop and validate a new sandwich ELISA test for the quantification of Pacreatitis Associated Protein in pig faecal samples. Finally, an observational study on a new Oxidative Stress Index (OSi) was conducted on dairy cows during the transition period. The driving hypothesis was that a composed index, as OSi, predicts more accurately the oxidative status than the evaluation of reactive oxygen species or serum antioxidant capacity separately. Furthermore, the relationship between indexes of oxidative status and markers of energy balance as blood free fatty acids and β-hydroxybutyrate, was determined.

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VERSO, L. LO. « Modulation of gut health in monogastric animals through nutritional additives ». Doctoral thesis, Università degli Studi di Milano, 2012. http://hdl.handle.net/2434/171958.

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There is a wide interest in developing management and feeding strategies to stimulate gut development and health in monogastric animals. The ultimate aim of these strategies is to improve productivity, while minimizing the use of antibiotics and rather expensive feed ingredients: indeed, under practical conditions, animals don’t achieve the maximum of their growth performance potential. Large amounts of research have been conducted evaluating the impact of a wide range of feed ingredients and feed additives on various aspects of gut health and development in monogastric animals. The main objective of this thesis was to improve our knowledge on the properties of new additives as feeding strategy, in order to increase general health in piglets around weaning and poultry, with the aim to substitute antibiotics growth promoters. Three different trials were designed to study different strategies. In the first study proposed, the effects of plant extract administered through drinking water on post-weaning gut health of piglets were investigated. Phytogenic feed additives are plant-derived products used in animal feeding to improve the performance of agricultural livestock. The objective of the present work was to evaluate the effects of a novel plant extract derived from common food plants on performance and health of weaned piglets fed mixed diet. At weaning (24 d), a total of 144 piglets were allocated in two post-weaning rooms, using a 2x2 factorial arrangement; treatments were Plant Extracts, 0 (Control group) or 8 μl daily/piglet (PE group) and Feeding Regimen, Ad Libitum or Restricted (piglets fed from 8 AM to 8 PM). Plant Extracts were a liquid mixture administered through drinking water. Piglets were housed in pens of three; each pen represented one treatment replicate, with six pens per treatment per room. On day 9 of the trial, after an adaptation period, each piglet of room 2 was orally injected with 4 ml of a solution containing 109 cfu of the virulent E. coli 0149: F4(K88)-positive strain. Animals were weighed and growth performance were recorded weekly; fecal score was evaluated at the same time as the weighing. At 0, 14 and 35 days, fecal samples were collected for microbiological analysis, while at day 0, 6, 19 and 35, blood samples were obtained from one pig per pen. At the end of the trial (35 d), 24 animals (12 from Control groups and 12 from Plant Extract groups) among Restricted feeding piglets were selected according to their body weight and slaughtered; immediately after slaughtering, the gastro-intestinal tract was removed from each animal: the distal ileum was collected and examined to assess the ileum micro-anatomical structure, perform histometry and immunohistochemistry and determine intestinal inflammatory parameters. PE supplementation enhanced ADG during the last week of the trial (P=0.007) and reduced FCR during the second (P=0.009) and the last weeks (P=0.04), and considering the overall period (P=0.01); a lower fecal score was observed in PE piglets (P<0.01). On day 35, lower fecal E.Coli (P=0.02) and Entrobacteriaceae (P=0.009) concentrations were determined in PE animals compared to control ones. Ileum crypts from PE piglets were deeper in challenged animals in comparison with not-challenged ones (P<0.05); number of mucosal macrophages was higher in Control challenged animals (P<0.05): in particular, number of mucosal macrophages in PE challenged piglets was similar to that one identified in not challenged Controls. PE supplementation also increased GSH-Px plasma concentration at d 6 (P=0.02) and tended to lower value of MDA at day 6 (P=0.07) and to increase value of T-AOC at the end of the trial (P=0.07). Hence, our results confirmed the possible protective functional role of the plant extracts mixture after the bacterial challenge: we can postulate that the use of plant extracts may be useful in the prevention of post-weaning diarrhea with an associated improvement in performance. The aim of the second trial was to evaluate the effect of the administration of mannanooligosaccharides (MOS) on growth performance, microbial population in feces and cecum and potential alteration of intestinal histomorphometric and gene expression of some intestinal inflammatory parameters of piglets fed a low digestible diet. Forty-eight weaned piglets (6.72 ± 0.32 kg of BW, 24 d of age) were used in a 35-d experiment and randomly allotted to 2 dietary treatments: basal diet (Control) and basal diet + 0.2 % MOS. Growth performance were recorded weekly, fecal samples were collected at 0, 14 and 35 d. At the end of trial, 10 piglets from each group were slaughtered and intestinal samples were collected. Data were analysed by a General Linear Model (GLM) procedure of SAS. BW, ADG, ADFI were not influenced by MOS supplementation; FCR was lower in treated animals in the last 2 weeks (P<0.05). Mean fecal score was improved in MOS piglets (P<0.01). At the end of trial treated piglets had higher Lactobacilli fecal count (P<0.05). No difference was detected among groups for Coliforms, while lower Clostridia occurred on day 14 in MOS piglets (P<0.05). Intestinal villi height in the duodenum was higher in MOS than Control (P<0.05). MOS supplementation also led to significant increase of NO production in ileal mucosa (P<0.05); finally, MOS suppressed mRNA relative expression of pro-inflammatory genes for IL-1α, IL-1β, IL-6 and TLR2 (P<0.05), for TLR4 (P<0.01) and for TNF (P<0.001), while there was no effect on IL-10 and PPARγ expression. Results indicate that MOS supplementation improved feed efficiency and intestinal morphometry of piglets fed low digestible diet. The third study was carried out to determine the effects of a probiotic mixture containing two strains of Lactobacillus on growth performance, carcass composition, blood lipids, digestive enzyme activity and intestinal microbiota in broiler chickens. Two dietary treatments, consisting of basal diet (control) and basal diet supplemented with combination of L. farciminis and L. rhamnosus were fed to 392 one day-old Ross 708 broiler chicks for 7 weeks. Each treatment had 28 replicates of 7 broilers. The results showed that body weight gain was improved in broilers fed probiotics diet compared to controls during 0-42 d (P<0.001) but not 43-49 d of age. Probiotic fed chicks had transitorily higher serum total cholesterol (P=0.02) and high-density lipoprotein cholesterol (P<0.008) at 28 d of age. Serum total protein was higher at 28 d of age (P=0.02) and lower at 49 d of age (P=0.001) in probiotics fed chicks compared to controls. Probiotics tended to increase abdominal fat percentage at 49 d of age (P<0.10). No difference in enzyme activity of small intestine digesta was observed. Dietary probiotics markedly increased Lactobacilli (P=0.01) and total Anaerobes (P≤0.01) counts and decreased Coliform (P=0.01) and total Aerobe counts (P≤0.01) in small intestine and caecum. The overall results demonstrated that dietary inclusion of a mixture of L. farciminis and L. rhamnosus could promote the growth and positively modulate intestinal microbiota in broiler chickens.

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Saccone, F. « CELL-BASED BIOASSAYS FOR TESTING BIOACTIVE COMPOUNDS IN FARM ANIMALS ». Doctoral thesis, Università degli Studi di Milano, 2013. http://hdl.handle.net/2434/216692.

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Cell-based assays can be adopted as in vitro method to evaluate the bioavailability and functionality of different nutraceutical and bioactive compounds, particularly in view of the need to use alternatives to animal studies. The interest in these bioactive compounds in animal sciences is not only related to medical research. It also represents an enormous benefit for health food companies and the animal produce sector in general. The general aim of my PhD study was to study nutraceutical effects at a cellular level in response to different stress challenges. In the first section of my thesis, the protective role of α-tocopherol in counteracting the cytotoxicity and DNA damage induced by Ochratoxin A (OTA) in primary porcine fibroblast cell cultures (ear and embryo), was determined by using the MTT assay, LDH release, DNA fragmentation, and TUNEL stain. The aim of the second section was to evaluate the protective role of bovine Lactoferrin (bLf), added to the culture medium, against lipopolysaccharide (LPS) cytotoxicity using the established bovine mammary epithelial cell line BME-UV1 as an in vitro model of the bovine mammary epithelium. In addition, we assessed whether BME-UV1 cells were able to express endogenous bLf after in vitro exposure to LPS. A further objective of my thesis work was to use cell-based bioassays to investigate the plasmin-plasminogen system. This system plays a key role in cellular responses, and is involved both in physiological and in pathological conditions in the mammary gland. The aim of the third section was to determine the effect of growth factors (IGF-1 and EGF) and three hormones (insulin, dexamethasone, and prolactin) on the expression of plasminogen activator (PA)-related genes (u-PA, u-PAR, PAI-1, PAI-2) and BME-UV1 cell proliferation. In addition we investigated the effects of E. coli LPS on cell viability, the modulation of cell-associated u-PA activity and the regulation of u-PA and u-PAR RNA expression in BME-UV1 cells. Below are more details on what each section covers: The first section reports how the role of α-tocopherol in counteracting OTA toxicity was evaluated in various experimental conditions using primary porcine fibroblasts. Cells showed a dose-, time- and origin-dependent (ear vs. embryo) sensitivity to ochratoxin A. Pre-incubation for 3 h with 1 nM α-tocopherol significantly (P < 0.01) reduced OTA cytotoxicity, lactate dehydrogenase release and DNA damage in both fibroblast cultures. These findings indicate that α-tocopherol administration may counteract short-term OTA toxicity, thus supporting its defensive role at a cell membrane level. The second section describes how BME-UV1 was used as an in vitro model to evaluate the protective role of exogenous bovine Lf (bLf) against the cytotoxic damage induced by bacterial lipopolysaccharides (LPS). Exogenous bLf showed a protective effect against endotoxin cytotoxicity, which could be mediated by the LPS-neutralizing capability of bLf. In addition, in BME-UV1 cells the response to LPS exposure did not involve endogenous bLf mRNA expression, suggesting that this cell line lacks functional LPS-responsive elements. The third section details how cell proliferation was measured using the MTT assay and direct cell enumeration on BME-UV1 treated with physiological stimuli. Results showed that both IGF-1 and EGF increased cell proliferation. Neither of the growth factors had any effect on the expression of PAI-1 and PAI-2. In line with changes in gene expression, EGF and IGF-1 up regulated total cell-associated, membrane-bound and secreted u-PA activity. Dexamethasone alone and when combined with insulin or prolactin up regulated the gene expression of both PAI- and PAI-2, but not that of u-PA and u-PAR without affecting cell proliferation. Total decreased cell-associated, membrane-bound and secreted u-PA activity was detected in cells cultured in the presence of dexamethasone when combined with insulin or prolactin. However no such effect was observed in the presence of dexamethasone alone. This thus suggests that when dexamethasone acts synergistically with prolactin or insulin it inhibits the activation of the plasmin-plasminogen system, but this inhibition is not correlated with any changes in cell proliferation. In addition, the plasmin-plasminogen system was examined, using the BME-UV1 cell model, in order to evaluate the effects of Escherichia coli LPS on cell viability, the modulation of cell-associated u-PA activity, and the regulation of u-PA and u-PA receptor (u-PAR) RNA expression. LPS did not affect cell viability, but led to an increase in u-PA activity, with the maximum response after 6 h of incubation. In addition, u-PA and u-PAR mRNA expression were both up-regulated in BME-UV1 cells after 3 h of incubation with LPS. These data indicated that E. coli LPS increased u-PA activity and RNA expression of u-PA and u-PAR in BME-UV1 cells, thus strengthening the role of the PA system during pathological processes. In conclusion, the application of appropriate in vitro models represents a fundamental requirement for the study of cellular responses to different stimuli as in the case covered in my thesis regarding nutraceutical compounds. Cell-based assays are a valuable tool for assessing fundamental regulatory mechanisms at a cellular level, such as the plasmin-plasminogen system. Cell-based assays allow both the functionality of nutraceutical and cellular response mechanisms to be evaluated reducing use animal models in the preliminary study phase. Obviously, data obtained in cell culture models must be interpreted carefully, since this system represents a simplification of the intricacies of the numerous reactions and interactions that occur in vivo.

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GIORGI, SILVIA. « NUTRITIONAL STRATEGIES FOR IMPROVING THE GUT HEALTH OF MONOGASTRIC ANIMALS ». Doctoral thesis, Università degli Studi di Milano, 2021. http://hdl.handle.net/2434/858928.

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Optimal gastrointestinal functionality and health is essential for sustainable animal production, especially considering that nowadays, the challenge in livestock sector is to maintain a high productivity and food security in a sustainable way, reducing the use of antimicrobials. Nutritional strategies that aim to improve animals’ performance preserving their intestinal health, are essential for achieving these goals. Therefore, in the present thesis, various nutritional interventions were evaluated, using short and medium chain fatty acids in particular, on the growth and intestinal well-being of pigs. The purpose of this thesis was to: 1) evaluate the effects of an innovative form of a medium chain fatty acid, lauric acid saponified with calcium, supplemented in post-weaning piglet diet on their growth and gut health and as a possible alternative to reduce the use of antibiotics; 2) asses the effectiveness of the combination of a short chain fatty acid (tributyrin) and a medium chain fatty acid (monolaurin) in post-weaning piglet diet on their growth performance and some gut health parameters; 3) evaluate the effects of lauric acid saponified with calcium administered to sows diet starting from the last 3 weeks of gestation, on sows productivity and on the growth performance and health of their offspring; 4) to assess the effect of fatty acids and different milk fractions on porcine IPEC-J2 cell line proliferation and viability. The results presented in this thesis highlight how short and medium chain fatty acids are effective candidates for improving animal health, reducing the use of antibiotics. This may contribute to the development of a more sustainable livestock production system based on the respect of animal health and the reduction of antimicrobials, as recommended by the “One Health” approach. However, further investigations are necessary to better understand the mechanisms of action, the dosage and the best forms of administration of short and medium chain fatty acids (alone or synergistically) integrated in pigs’ diets, in particular during weaning, to further improve their growth performance and gut health.

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CHIAPPARINI, SARA. « IMPROVEMENT IN ANIMAL HEALTH AND PRODUCT QUALITY THROUGH DIETARY MANIPULATION ». Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/707396.

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La principale sfida nel settore zootecnico è mantere un’elevata produttivita e la sicurezza degli alimenti in modo sostenibile, riducendo l’utilizzo degli antimicrobici. Diverse strategie alimentari risultano indispensabili per il raggiungimento di questi obiettivi, in quanto sono in grado di migliorare le performance e la salute degli animali e la qualità dei prodotti. In particolare, sono state valutate diverse integrazioni dietetiche con estratti naturali e molecole bioattive. L’obiettivo della tesi è stato: 1) Studiare l’utilizzo di integrazioni dietetiche con alghe nella specie suina. 2) Valutare gli effetti dell’integrazione dietetica nel suinetto in post svezzamento con estratti naturali biotecnologici su performance di crescita, parametri immunitari e lo status antiossidante. 3) Valutare gli effetti dell’integrazione dietetica con alghe brune e polifenoli su parametri riproduttivi e status antiossidante delle coniglie. 4) Valutare gli effetti dell’integrazione dietetica con alghe brune e polifenoli sulle performance di crescita e qualità della carne in conigli in accrescimento. Gli studi mostrano che l’integrazione dietetica con sostanze naturali riuslta un approccio sostenibile per migliorare la salute, i parametri produttivi e la qualità dei prodotti nella specie suina e cunicola. In particolare, sono state studiate alcune integrazioni dietetiche con estratti biotecnologici e con una miscela di alghe brune e polifenoli. I risultati hanno dimostrato l’efficacia di queste sostanze nel modulare positivamente la la salute degli animali, con conseguente riduzione di antibiotici. Tali strategie alimentari possono quindi contribuire allo sviluppo di un sistema produttivo sostenibile migliorando la salute animale e la qualità dei prodotti, riducendo l’impatto ambientale come richiesto dall’approccio One Health. Considerando l’eterogeneità delle sostanze naturali, si rendono necessarie ulteriori indagini per approfondire le conoscenze relative ai diversi meccanismi d’azione e ai corretti dosaggi da applicare nelle diverse specie d’interesse zootrecnico.
The challenge in livestock sector is to maintain a high productivity and food security in a sustainable way, reducing the use of antimicrobials. For these reasons, the use of sustainable dietary interventions seems to be a valuable approach in order to enhance animal performance, health and product quality. So, a nutritional approach, using dietary integration with biotechnological bioactive compounds or sustainable integration are investigated. The aim of this thesis was to: 1) summarize the dietary intervention with seaweed in pig specie 2) evaluate the effects of dietary integration with biotechnological extract in post weaning piglets on growth, immune parameters and oxidative status 3) evaluate the effectiveness of brown seaweed and polyphenols mixture on rabbit does reproductive performances and antioxidant status and 4) evaluate the effect of brown seaweed and polyphenols mixture on growth and meat quality parameters in rabbit. The present experimental studies highlight that dietary manipulation with natural substances is a useful approach to improve rabbits and piglet’s health, productive parameters and product quality in a sustainable way. In particular, the use of dietary biotechnological extract and brown seaweed and plant polyphenols mixture was investigated. This data highlight that natural extracts are effective candidates to improve animal health, reducing the use of antibiotics. This will contribute to the development of a sustainable production system, in order to enhance animal health, product quality and to reduce the environmental impact, as recommended by the One health approach. Considering the heterogeneity of herbs, spices and botanicals, further investigations are required to deepen our knowledge about the mechanism of actions and dosage of seaweeds and polyphenols mixture.

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Thèses sur le sujet « Alimentazione animale »

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