The microbial populations in the gastrointestinal tracts of poultry play an important role in normal digestive processes and in maintaining animal health. The purpose of this study was to evaluate the effects of probiotics, prebiotics and synbiotics on the growth parameters, gut ecosystem, histology and immune function. In this study, four experiments one in vitro and three in vivo were conducted using specific pathogen free (SPF) and Hubbard broiler chickens. The first experiment was designed to determine the influence of inulin as an effective prebiotic on lactic acid bacteria (LAB) strains, and to screen LAB for selection as a source of chicken probiotic. Eight strains of LAB were isolated from chicken caeca and three strains from the Plymouth University culture collection were screened for potential probiotic properties for growth in inulin from Jerusalem artichoke (Helianthus tuberosus) and commercial inulin (Frutafit® HD, Netherlands). Lactobacillus animalis JCM 8692 strain isolated from chicken caeca showed the highest auto-aggregation and co-aggregation ability, resistance to acidity and bile salts, strong suppression of pathogens and ability to adhere to epithelial cells compared with other isolated strains. The second experiment was conducted to investigate the influence of commercial inulin and Jerusalem artichoke tubers as prebiotic supplementation on the diversity of the caecal microflora, jejunum histology and immune organ of SPF chickens. This investigation has found that inulin which was extracted from JA had a similar result when compared with commercial inulin and could be a suitable candidate for an inulin source in broiler diets. The third experiment was conducted to investigate the influence of Bactocell® (PRO1) and Lb. animalis (PRO2) as probiotic supplements on broiler chickens. EPEF was significantly increased in probiotic1 and probiotic2 compared with control (311.03, 309.87 and 260.06) respectively. Both types of probiotics supported the growth of chicks healthy and could be a suitable candidate as a source of probiotic in broiler diet. The fourth experiment was conducted to investigate the influence of dietary supplementation of a probiotic (Lb. animalis), a prebiotic JA tuber and a combination of both (Synbiotic) in broiler chickens. Growth performance was improved in all additive supplementation compared with the control group. EPEF was increased in probiotic, prebiotic and synbiotic compared with control (290.8±11.8, 300.9±3.86, 322.1±7.09 and 262.3±5.94) respectively. Beneficial bacteria in the guts of chicks fed probiotic, prebiotic and synbiotic was increased compared with chicks fed control diet. The diversity of microbial population in the gastrointestinal tract of chickens improved due to additives. The intestinal villus lengths and microvilli density was improved in all additives supplementation in comparison with control. Overall, it was concluded that probiotic, prebiotic and synbiotics can positively affect production performance and can improve the gut health.

Restrições econômicas e ambientais trazem a necessidade de substituir a farinha de peixe em dietas de organismos aquáticos por matérias-primas menos dispendiosas de origem vegetal. Entretanto, tais fontes proteicas vegetais possuem fatores antinutricionais que podem ter efeitos negativos sobre o sistema digestório dos peixes, alterando a saúde e, em consequência, a produção. O objetivo deste trabalho foi avaliar a digestibilidade e alterações na histologia do epitélio intestinal de juvenis do Characiforme carnívoro dourado, Salminus brasiliensis, alimentados com dietas contendo farelo de soja (FSO), farelo de algodão (FAl) e farelo de amendoim (FAM) como principais fontes proteicas. Foram conduzidos dois experimentos: digestibilidade (Ensaio I) e histológico (Ensaio II). O Ensaio I foi conduzido em protocolo padrão utilizando dietas práticas adicionadas do marcador inerte óxido de crômio III (CR2O3) e sistema Guelph modificado para coleta de fezes e consequente cálculo dos coeficientes de digestibilidade. No Ensaio II as mesmas fonte proteicas - FSO, FAL e FAM - foram utilizadas em substituição à proteína da farinha de peixe em uma dieta controle com cinco níveis de inclusão: 0 (controle), 25,0 %; 50%; 75,0% e 100%, em um delineamento inteiramente aleatorizado (n=3). O experimento teve a duração de 40 dias, e as coleta de amostras de tecido foram feitas aos 20 e 40 dias. As amostras do intestino posterior foram analisadas quanto às características histológicas e morfológicas, além de quantificação de células caliciformes e análise histomorfométrica do tecido intestinal. Não foram registradas diferenças para os coeficientes de digestibilidade da proteína e energia no ensaio de digestibilidade. O ensaio de desempenho mostrou que a inclusão de FAM e FAL nas dietas melhora o consumo de alimento comparativamente ao FSO Em relação as variáveis histológicas, os níveis que condicionaram alterações significativas nos parâmetros morfométricos foram FSO50 e FOS75. O FSO50 promoveu uma redução das dobras intestinais aos 20 dias, porém aos 40 dias houve aumento na altura das dobras, no espessamento da lâmina-própria e aumento na densidade das células caliciformes. Considerando a microscopia de varredura, sinais acentuados de enterite foram registrados. A alteração na morfologia e histologia do epitélio intestinal foi reflexo da interação de efeitos dos fatores antinutricionais presentes em cada fonte proteica vegetal. Consequentemente, registrou-se menor ganho de peso, crescimento e diminuição da homeostase intestinal, embora os melhores consumos e CAA fossem registrados para os peixes alimentados com FAL e FP. Conclui-se que o FSO causou enterite nos juvenis de dourado e FAL e FAM podem ser utilizados na alimentação de dourado. / Economic and environment constraints have brought the need to replace fishmeal (FM) in diets of aquatic organisms by less expensive feedstuff, especially dietary protein sources. However, such protein sources generally of plant origin, e.g. soybean meal, have antinutritional factors that can negatively affect digestive system of the fish, impairing health and consequently, production. To identify possible effects of plant protein sources in the diets for carnivore fish, this study evaluated effects of various dietary plant protein sources on digestibility, performance, histology of the intestinal epithelium of the carnivore, Neotropical Characin dourado, Salminus brasiliensis, fed plant protein-based diets. A digestibility trial was carried out in standard protocol using diets with inert marker chromium oxide III (Cr2O3) and modified system Guelph for feces. A performance test evaluated the use of three plant protein sources, soybean meal (SBM), cottonseed meal (CTM) and peanut meal (PTM) as surrogate protein source to fishmeal in a practical diet in five levels inclusion: 0 (control); 25.0%; 50.0%; 75.0% and 100%, in a randomized block design (n=3). Samples of tissue of intestinal tract of fish were collected in the distal segment at 20 and 40 days of the feeding period, and analyzed for histological and morphological characteristics. No differences were recorded for apparent digestibility coefficients (ADC) of feedstuff and energy and protein of feedstuffs. Dietary CM and PM elicited better feed consumption comparatively to the other feedstuff, Fish fed diet diet SBM50 presented reduction of intestinal folds at 20 days, but at 40 days had increased folds height, lamina propria thickening, and increased goblet cell density. Considering a scanning microscopy, evident signs of enteritis were registered. The alteration in the morphology and histology of the intestinal epithelium reflected the interaction of effects of the antinutritional factors present in each vegetable protein source, resulting in lower weight gain, growth and decreased intestinal homeostasis, even though best feed consumption and ADC were registered for fish fed CTM and FM.Concluded that SBM caused enteritis and CTM and PM can be used in feeding dourado.

Restrições econômicas e ambientais trazem a necessidade de substituir a farinha de peixe em dietas de organismos aquáticos por matérias-primas menos dispendiosas de origem vegetal. Entretanto, tais fontes proteicas vegetais possuem fatores antinutricionais que podem ter efeitos negativos sobre o sistema digestório dos peixes, alterando a saúde e, em consequência, a produção. O objetivo deste trabalho foi avaliar a digestibilidade e alterações na histologia do epitélio intestinal de juvenis do Characiforme carnívoro dourado, Salminus brasiliensis, alimentados com dietas contendo farelo de soja (FSO), farelo de algodão (FAl) e farelo de amendoim (FAM) como principais fontes proteicas. Foram conduzidos dois experimentos: digestibilidade (Ensaio I) e histológico (Ensaio II). O Ensaio I foi conduzido em protocolo padrão utilizando dietas práticas adicionadas do marcador inerte óxido de crômio III (CR2O3) e sistema Guelph modificado para coleta de fezes e consequente cálculo dos coeficientes de digestibilidade. No Ensaio II as mesmas fonte proteicas - FSO, FAL e FAM - foram utilizadas em substituição à proteína da farinha de peixe em uma dieta controle com cinco níveis de inclusão: 0 (controle), 25,0 %; 50%; 75,0% e 100%, em um delineamento inteiramente aleatorizado (n=3). O experimento teve a duração de 40 dias, e as coleta de amostras de tecido foram feitas aos 20 e 40 dias. As amostras do intestino posterior foram analisadas quanto às características histológicas e morfológicas, além de quantificação de células caliciformes e análise histomorfométrica do tecido intestinal. Não foram registradas diferenças para os coeficientes de digestibilidade da proteína e energia no ensaio de digestibilidade. O ensaio de desempenho mostrou que a inclusão de FAM e FAL nas dietas melhora o consumo de alimento comparativamente ao FSO Em relação as variáveis histológicas, os níveis que condicionaram alterações significativas nos parâmetros morfométricos foram FSO50 e FOS75. O FSO50 promoveu uma redução das dobras intestinais aos 20 dias, porém aos 40 dias houve aumento na altura das dobras, no espessamento da lâmina-própria e aumento na densidade das células caliciformes. Considerando a microscopia de varredura, sinais acentuados de enterite foram registrados. A alteração na morfologia e histologia do epitélio intestinal foi reflexo da interação de efeitos dos fatores antinutricionais presentes em cada fonte proteica vegetal. Consequentemente, registrou-se menor ganho de peso, crescimento e diminuição da homeostase intestinal, embora os melhores consumos e CAA fossem registrados para os peixes alimentados com FAL e FP. Conclui-se que o FSO causou enterite nos juvenis de dourado e FAL e FAM podem ser utilizados na alimentação de dourado. / Economic and environment constraints have brought the need to replace fishmeal (FM) in diets of aquatic organisms by less expensive feedstuff, especially dietary protein sources. However, such protein sources generally of plant origin, e.g. soybean meal, have antinutritional factors that can negatively affect digestive system of the fish, impairing health and consequently, production. To identify possible effects of plant protein sources in the diets for carnivore fish, this study evaluated effects of various dietary plant protein sources on digestibility, performance, histology of the intestinal epithelium of the carnivore, Neotropical Characin dourado, Salminus brasiliensis, fed plant protein-based diets. A digestibility trial was carried out in standard protocol using diets with inert marker chromium oxide III (Cr2O3) and modified system Guelph for feces. A performance test evaluated the use of three plant protein sources, soybean meal (SBM), cottonseed meal (CTM) and peanut meal (PTM) as surrogate protein source to fishmeal in a practical diet in five levels inclusion: 0 (control); 25.0%; 50.0%; 75.0% and 100%, in a randomized block design (n=3). Samples of tissue of intestinal tract of fish were collected in the distal segment at 20 and 40 days of the feeding period, and analyzed for histological and morphological characteristics. No differences were recorded for apparent digestibility coefficients (ADC) of feedstuff and energy and protein of feedstuffs. Dietary CM and PM elicited better feed consumption comparatively to the other feedstuff, Fish fed diet diet SBM50 presented reduction of intestinal folds at 20 days, but at 40 days had increased folds height, lamina propria thickening, and increased goblet cell density. Considering a scanning microscopy, evident signs of enteritis were registered. The alteration in the morphology and histology of the intestinal epithelium reflected the interaction of effects of the antinutritional factors present in each vegetable protein source, resulting in lower weight gain, growth and decreased intestinal homeostasis, even though best feed consumption and ADC were registered for fish fed CTM and FM.Concluded that SBM caused enteritis and CTM and PM can be used in feeding dourado.

En la presente Tesis Doctoral se utilizaron cebada y remolacha como fuentes alternativas de carbohidratos en dietas para trucha arcoíris con el objetivo de evaluar su efecto sobre parámetros productivos, histología hepática e intestinal, estrés y calidad de la carne. Los marcadores estudiados fueron los mismo tanto para los experimentos de cebada como de remolacha. En las pruebas de la cebada se utilizaron concentraciones crecientes de este ingrediente (0-32%) en la dieta, se inició con un peso medio de 127.72 ± 5.65 g y se finalizó cuando alcanzaron el peso comercial al cabo de 84 días. En las pruebas de remolacha se utilizaron dos niveles de remolacha (14% y 28%) y dos de betaína (0.9% y 1.63%), se inició con un peso medio de 69 ± 2.2 g y se finalizó cuando los peces alcanzaron el peso comercial al cabo de 105 días. La inclusión de cebada en dietas de trucha arcoíris no mostró diferencias significativas en los parámetros de crecimiento ni biométricos. La inclusión de 14% remolacha y 0.9% betaína no afectó al crecimiento, parámetros nutritivos, biométricos y retenciones de nutrientes en comparación con el control, concentraciones mayores de remolacha y betaína tuvieron un efecto negativo. Cuando se estudiaron los parámetros histológicos y morfométricos en hígado e intestino, los resultados mostraron que los peces alimentados con concentraciones crecientes de cebada mostraron hepatocitos más pequeños, mientras que los peces alimentados con remolacha y betaína presentaban hepatocitos más grandes, en ambos casos el hígado mostró un menor nivel de vacuolización. La concentración de cebada de un 8% produjo un efecto negativo a nivel morfológico del intestino, sin embargo, la inclusión de remolacha no produjo ningún efecto. Los peces fueron sometidos a estrés por ausencia de oxígeno y aumento de densidad durante 10 minutos. Cuando el estrés fue analizado a nivel bioquímico los resultados mostraron que a niveles basales, la inclusión de cebada y remolacha no causó ningún cambio en los niveles de cortisol, glucosa y MDA, aunque los valores basales de lactato fueron significativamente más bajos en los peces alimentados con remolacha y betaína. Treinta minutos después del estrés la concentración de cortisol, glucosa y lactato aumentó significativamente en los peces de todos los grupos y la concentración de MDA disminuyó. La inclusión de cebada mostró valores más bajos de cortisol, glucosa y lactato que la dieta control. Cuando los peces alcanzaron el peso comercial se analizó la calidad de los filetes y las propiedades antioxidantes. En ambas pruebas los peces alimentados con los ingredientes objeto de estudio mostraron valores de actividad de agua más bajos y una mejora en la textura y el color de los filetes comparado con los peces alimentados con la dieta control. La inclusión de remolacha y betaína no tuvo ningún efecto sobre los parámetros oxidativos del filete, mientras que la inclusión de cebada inhibió su oxidación lipídica. Concentraciones de cebada por encima del 8% mejoraron la actividad antioxidante de los filetes y aumentaron el contenido en alpha-tocoferol, sin embargo, los peces alimentados con remolacha y betaína mostraron un mayor contenido en flavonoides y fenólico pero no se observó ningún efecto sobre las propiedades antioxidantes del filete. Por último, cuando se llevó a cabo el análisis sensorial se observó que los peces alimentados con dietas con más de un 8% de cebada mostraron unas agallas más rojas y mejor textura, además de un color rojo del filete más intenso, parámetros que se correlacionan con una mejora de la frescura del pescado. Sin embargo, la inclusión de cebada o remolacha en dietas de trucha arco iris no tuvo ningún efecto sobre la aceptabilidad de los filetes. / The current Doctoral Thesis used barley and red beet as alternative carbohydrate sources in rainbow trout diets. The aim was to evaluate their effect on productive, histological and morphometric parameters, their effect on biochemical indexes after an acute stress and their effect on the quality of rainbow trout (Oncorhynchus mykiss). The different markers studied were the same in the barley and red beet experiments. In the barley experiment, increasing concentrations of barley (0-32%) were used in the diet, starting with an average weight of 127.72 ± 5.65 g and ending when they reached commercial weight after 84 days. In the red beet experiment, two red beet levels (14% and 28%) and two betaine levels (0.9% and 1.63%) were used, starting with an average weight of 69 ± 2.2 g and finishing when they reached commercial weight at the end of 105 days. The inclusion of barley in rainbow trout diets did not show significant differences in growth and biometric parameters. While the inclusion of 14% of red beet and 0.9% betaine did not affect growth, nutritive or biometric parameters and nutrient retentions compared to control, higher red beet and betaine concentrations showed a negative effect. When the histological and morphometric parameters were studied in liver and intestine, the results showed that fish fed at high barley concentrations showed smaller hepatocytes than control, while hepatocytes were larger in fish fed with red beet and betaine than control, however, in both cases, the liver had a lower level of vacuolization. Barley inclusion at 8% produced a negative effect at intestine morphological level; however, no effects were observed with the inclusion of red beet. Fish were submitted to stress, a lack of oxygen and increased of fish density, during 10 minutes. The results showed that at basal levels, the inclusion of barley and red beet did not cause any change in cortisol, glucose and MDA levels, although basal lactate values were significantly lower in the fish fed with red beet and betaine. Thirty minutes after stress the concentration of cortisol, glucose and lactate increased significantly in the fish of all groups and the concentration of MDA decreased. The inclusion of barley showed lower cortisol, glucose and lactate values than control. When fish reached commercial weight, the quality of the fillets and antioxidant properties were analysed. In both trials, fish fed with the experimental ingredients showed lower water activity values and textural and colour properties were enhanced. Red beet and betaine inclusion did not show any effect on the oxidative parameters of the fillets, while the inclusion of barley showed an inhibitory effect on fillets lipid oxidation. Concentrations of barley above 8% improved the antioxidant activity of the fillets and increased the content of alpha-tocopherol, however, fish fed with red beet and betaine showed a higher content of flavonoids and phenolics but no effect on the antioxidant properties of the fillet. Finally, when the sensory analysis was carried out, it was observed that fish fed diets with more than 8% barley showed redder gills and better texture than control, in addition to a more intense red colour of the fillet, these characteristics are correlated with an improvement of fish freshness. However, the inclusion of barley or red beet in rainbow trout diets had no effect on the acceptability of fillets. / En la present tesi doctoral es van utilitzar ordi i remolatxa com a fonts alternatives de carbohidrats en dietes per a truita amb l'objectiu d'avaluar el seu efecte sobre paràmetres productius, histologia hepàtica i intestinal, estrès i qualitat de la carn. Els marcadors estudiants fòren els mateixos en els experiments d`ordi I remolatxa. En les proves de l'ordi es van utilitzar concentracions creixents d'aquest ingredient (0-32%), es va iniciar amb un pes mitjà de 127.72 ± 5.65 g i es va finalitzar quan van arribar al pes comercial al cap de 84 dies. En les proves de remolatxa es van utilitzar dos nivells de remolatxa (14% i 28%) i dos de betaïna (0.9% i 1.63%), es va iniciar amb un pes mitjà de 69 ± 2.2 g i es va finalitzar quan els peixos van aconseguir el pes comercial al cap de 105 dies. La inclusió d'ordi en dietes de truita no va mostrar diferències significatives en els paràmetres de creixement i biomètrics. La inclusió de 14% remolatxa i 0,9% betaïna no va afectar el creixement, paràmetres nutritius, biomètrics i retencions de nutrients en comparació amb el control, concentracions majors de remolatxa i betaïna van tenir un efecte negatiu. Quan es van estudiar els paràmetres histològics i morfomètrics en fetge i intestí, els resultats van mostrar que els peixos alimentats amb concentracions creixents d'ordi tenien hepatòcits més petits, mentres que els peixos alimentats amb remolatxa i betaïna presentaven hepatòcits més grans, i en ambdós casos el fetge va mostrar un menor nivell de vacuolització. La concentracion d'ordi d'un 8% va produir un efecte negatiu a nivell morfològic de l'intestí, mentres que la inclusió de remolatxa no va produir cap efecte a nivell d'intestí. Els peixos van ser sotmesos a estrès per absència d'oxigen i augment de densitat durant 10 minuts. Quan l'estrès va ser analitzat a nivell bioquímic els resultats van mostrar que a nivells basals, la inclusió d'ordi i remolatxa no va causar cap canvi en els nivells de cortisol, glucosa i MDA, encara que els valors basals de lactat van ser significativament més baixos en els peixos alimentats amb remolatxa i betaïna. 30 minuts després de l'estrès la concentració de cortisol, glucosa i lactat va augmentar significativament en els peixos de tots els grups i la concentració de MDA va disminuir. La inclusió d`ordi va mostrar valors més baixos de cortisol, glucosa i lactat que la dieta control. Quan els peixos van aconseguir el pes comercial es va analitzar la qualitat dels filets i propietats antioxidants. En ambdues proves els peixos alimentats amb els ingredients objecte d'estudi van mostrar valors d'activitat d'aigua més baixos i una millora en la textura i el color dels filets comparat amb els peixos alimentats amb la dieta control. La inclusió de remolatxa i betaïna no va tenir cap efecte sobre els paràmetres oxidatius del filet, mentre que la inclusió d'ordi va inhibir l'oxidació lipídica dels filets. Concentracions d'ordi per sobre del 8% van millorar l'activitat antioxidant dels filets i van augmentar el contingut en alpha-tocoferol, però, els peixos alimentats amb remolatxa i betaïna van mostrar un major contingut en flavonoides i fenòlic però no es va observar cap efecte sobre les propietats antioxidants del filet. Finalment, quan es va dur a terme l'anàlisi sensorial es va observar que els peixos alimentats amb dietes amb més d'un 8% d'ordi van mostrar unes ganyes més vermelles i millor textura, a més d'un color vermell del filet més intens, paràmetres que es correlacionen amb una millora de la frescor del peix. No obstant això, la inclusió d'ordi o remolatxa en dietes de truita no va tenir cap efecte sobre l'acceptabilitat dels filets. / Pinedo Gil, J. (2018). Study of novel carbohydrate sources on rainbow trout (Oncorhynchus mykiss) diets [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/107364 / TESIS