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Effects of different nutritional strategies on intestinal inflammation in pigsTugnoli, Benedetta <1986> January 1900 (has links)
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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Natural compounds to control clostridial and salmonella infections in food animalsMessina, Maria Rosaria <1982> 21 May 2010 (has links)
No description available.
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Miglioramento della qualità della carne suina: modificazioni della frazione lipidica nella filiera di produzione del suino pesanteBrogna, Nico <1973> 15 June 2007 (has links)
No description available.
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Micotossine e produzioni zootecniche: esperienze su galline ovaiole e suiniPaganelli, Riccardo <1976> 15 June 2007 (has links)
No description available.
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Development of non pharmaceutical strategies to improve intestinal health in weaning pigletsGrilli, Ester <1978> 15 June 2007 (has links)
No description available.
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Pet food: quality and quality improvementCipollini, Irene <1976> 10 April 2008 (has links)
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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Nutritional strategies to control mycotoxin damages in swinePizzamiglio, Valentina <1979> 10 April 2008 (has links)
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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Importanza dell'interazione tra la dieta, i microrganismi commensali e la microflora patogena, nel suino in svezzamentoDe Filippi, Sara <1977> 08 May 2008 (has links)
No description available.
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Impiego di additivi "naturali" nell'alimentazione del bovino da carnePastò, Luigina Fernanda <1974> 21 May 2010 (has links)
No description available.
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Muffe e micotossine: indicatori di attività fungina ed effetti dell' ocratossina nella gallina ovaiolaCanestrari, Giorgia <1980> 21 May 2010 (has links)
No description available.
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