Early training of hens: effects on the animal distribution in an aviary system

Submitted 2020-07-23 | Accepted 2020-08-12 | Available 2020-12-01https://doi.org/10.15414/afz.2020.23.mi-fpap.269-275The study aimed at evaluating if the training of hens at their arrival in the production farm affected the distribution of animals in the aviary. Training consisted in raising by hand animals found on litter after turning off the light during the first two weeks. A total of 1,800 hens, aged 17 weeks, were allocated in 8 pens of the aviary and assigned to the trained or untrained groups. From 18 to 26 weeks of age, two operators recorded the number of animals on the different parts of the aviary at two observation hours (morning and afternoon). The training decreased the rate of hens on the floor (23.5% vs. 24.5%; P<0.05) and increased the rate of those on the third level (9.26% vs. 8.73%). The rate of animals on the floor (24.4% vs. 23.6%; P=0.05) and on the second tiers (36.9% vs. 33.2%; P<0.001) was significantly higher at morning hours compared to afternoon, whereas the rate of animals on the first tiers (29.6% to 33.7%; P<0.001) and on the perches of the third level (8.84% to 9.25%; P<0.05) was lower. As the age advanced, the rate of hens on the floor significantly increased (21% to 25% from week 18 to 26); animals at the first tiers decreased from week 18 (35.3%) to weeks 20-25 to reach the minimum value at week 26 (27.9%); differences in animals on the second tiers were erratic; rate of animals on the third level was the lowest (7.13%) at week 18 and the highest (11.7%) at week 26.Keywords: aviary, laying hens, space use, nest lighting, observation hourReferencesAli, A. et al. (2016). Influence of genetic strain and access to litter on special distribution of 4 strains of laying hens in an aviary system. Poultry Science, 95, 2489–2502. 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Effects of dietary barley on rainbow trout exposed to an acute stress challenge

Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modifications of the content of this paper are prohibited.[EN] The present study evaluates the effect of dietary barley, based on its potential stress-relieving properties, on rainbow trout under acute stress challenge (hypoxia and crowding) and their recovery. Diets were formulated containing increasing barley concentrations (0, 4, 8, 16, 32%). Cortisol on plasma and fin, glucose and lactate plasma levels and malondialdehyde (MDA) in muscle were determined under normoxia before the stress test (basal levels), 30 min after the acute stress challenge and also during normoxia recovery (6 and 12 h after the stress). Results showed that at basal levels the inclusion of barley had no influence on cortisol, glucose nor on lactate values. After 30 min from the stress challenge, there was a significant increase in cortisol, glucose and lactate concentration in fish of all groups. Plasma cortisol showed the lowest levels in fish fed with diets at a medium (8%) of barley concentration and returned to basal levels 6 h after the stress stimulus with no differences between diets. Glucose values showed a less clear tendency 30 min after the stress challenge with lower levels in the control group, fish fed with 8% and 32% of barley in the diets and returned to basal levels in almost all the groups only 12 h after the stress challenge. Lactate showed the same trend as with glucose after the stress challenge but it returned to basal levels in 6 h. Interestingly, there was a significant decrease of lipid oxidation (MDA) in muscle soon after the stress test of fish fed with the highest barley levels. The present results suggest a potential positive effect of dietary barley on trout stress response.This work has been co-funded with FEDER and INIA funds. Julia Pinedo has been granted with the FPI-INIA grant number 21 (call 2012, BOE-2012-13337).Pinedo-Gil, J.; Martín-Diana, AB.; Bertotto, D.; Sanz-Calvo, M.; Jover Cerda, M.; Tomas-Vidal, A. (2019). Effects of dietary barley on rainbow trout exposed to an acute stress challenge. Aquaculture. 501:32-38. https://doi.org/10.1016/j.aquaculture.2018.10.070S323850

Effects of dietary inclusions of red beet and betaine on the acute stress response and muscle lipid peroxidation in rainbow trout

[EN] This study evaluates the effects of red beet (RB) and betaine on rainbow trout submitted to an acute stress challenge. A control diet was compared with four experimental diets in which red beet (14 and 28%) and betaine (0.9 and 1.63%) were incorporated in different concentrations according to a factorial design. Cortisol in plasma and fin, glucose and lactate plasma levels, and malondialdehide (MDA) in muscle were all measured before the stress challenge and 30 min and 6 and 12 h after the stress challenge as parameters to determine the diet effects. RB and betaine had no effect on cortisol, glucose, and MDA basal levels. However, lactate basal levels were significantly lower on fish fed with RB and betaine. Thirty minutes after the stress challenge, there was a significant increase in plasma and fin cortisol, glucose and lactate concentrations, although fish fed with diets containing RB and betaine showed significantly higher plasma cortisol values. MDA values of fish fed with 14% RB and 0.9% betaine were significantly higher than MDA values from fish fed with 28% RB and 1.63% betaine. After 6 and 12 h, plasma and fin cortisol and lactate levels recovered in a similar trend. Glucose plasma levels recovered in almost all groups 12 h after the stress. Also, MDA values recovered basal levels after 6 and 12 h. RB and betaine did not enhance the tolerance to the stress challenge compared to the control group, although the presence of these ingredients had no negative effect on any of the stress indicators.Pinedo-Gil, J.; Martín-Diana, AB.; Bertotto, D.; Sanz-Calvo, MÁ.; Jover Cerda, M.; Tomas-Vidal, A. (2018). Effects of dietary inclusions of red beet and betaine on the acute stress response and muscle lipid peroxidation in rainbow trout. 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J Exp Biol 216:4435–4442Gesto M, López-Patiño MA, Hernández J, Soengas JL, Míguez JM (2015) Gradation of the stress response in rainbow trout exposed to stressors of different severity: the role of brain serotonergic and dopaminergic systems. J Neuroendocrinol 27:131–141Hemre GI, Mommsen TP, Krogdahl Å (2002) Carbohydrates in fish nutrition: effects on growth, glucose metabolism and heptic enzymes. Aquac Nutr 8:175–194Ings JS, Vijayan MM, Servos MR (2012) Tissue-specific metabolic changes in response to an acute handling disturbance in juvenile rainbow trout exposed to municipal wastewater effluent. Aquat Toxicol 108:53–59Janssens PA, Waterman J (1988) Hormonal regulation of gluconeogenesis and glycogenolysis in carp (Cyprinus carpio) liver pieces cultured in vitro. Comp Biochem Physiol 91A:451–457Jeney G, Galeotti M, Volpatti D, Anderson DP (1997) Prevention of stress in rainbow trout (Oncorhynchus mykiss) fed diets containing different doses of glucan. 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Comp Biochem Physiol C 155:506–516Pichavant K, Maxime V, Thébault MT, Ollivier H, Garnier JP, Bousquet B, Diouris M, Boeuf G, Nonnotte G (2002) Effects of hypoxia and subsequent recovery on turbot (Scophthalmus maximus): hormonal changes and anaerobic metabolism. Mar Ecol Prog Ser 225:275–285Pinedo-Gil J, Tomás-Vidal A, Larrán-García AM, Tomás-Almenar C, Jover-Cerdá M, Sanz-Calvo MA, Martín-Diana AB (2017a) Enhancement of quality of rainbow trout (Oncorhynchus mykiss) flesh incorporating barley on diet without negative effect on rearing parameters. Aquacult Int 25:1005–1023. https://doi.org/10.1007/s10499-016-0091-0Pinedo-Gil J, Tomás-Vidal A, Jover-Cerdá M, Tomás-Almenar C, Sanz-Calvo MA, Martín-Diana AB (2017b) Red beet and betaine as ingredients in diets of rainbow trout (Oncorhynchus mykiss): effects on growth performance, nutrient retention and flesh quality. Arch Anim Nutr 71:486–505. https://doi.org/10.1080/1745039X.2017.1391503Rabeh NM (2015) Effect of red beetroot (Beta vulgaris L.) and its fresh juice against carbon tetrachloride induced hepatotoxicity in rats. World Appl Sci J 33(6):931–938Rollo A, Sulpizio R, Nardi M, Silvi S, Orpianesi C, Caggiano M, Cresci A, Carnevalli O (2006) Live microbial feed supplement in aquaculture for improvement of stress tolerance. Fish Physiol Biochem 32:167–177Sadoul B, Leguen I, Colson V, Friggens NC, Prunet P (2015) A multivariate analysis using physiology and behaviour to characterize robustness in two isogenic lines of rainbow trout exposed to a confinement stress. Physiol Behav 140:139–147Tan Q, Xie S, Zhu X, Lei W, Yang Y (2006) Effect of dietary carbohydrates sources on growth performance and utilization for gibel carp (Carassius auratus) and Chinese longsnout catfish (Leiocassis Longirostris Günther). 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Red beet and betaine as ingredients in diets of rainbow trout (Oncorhynchus mykiss): effects on growth performance, nutrient retention and flesh quality

[EN] The objective of the study was to evaluate the impact of different concentrations of dietary red beet and betaine on the growth performance and fish flesh quality of rainbow trout. Therefore, a control diet was compared with four diets in which two levels of red beet (14% and 28%) and betaine (0.9% and 1.63%) were incorporated in combination. The study was set up with an average body weight of 69 ± 2.2 g and finished when fish reached commercial weight (175¿250 g) after 105 d. The impact of the diets was studied based on the growth performance, biometric indexes, proximal composition, protein and fat retention efficiencies and apparent nutrient digestibility by fish reared on a recirculation system. Further estimates were the effect of red beet and betaine on the flesh proximate composition and quality of the final product (water activity, colour, texture, thiobarbituric acid reactive substances and sensory characteristics). Results showed that inclusion of 14% red beet and 0.9% betaine did not affect growth, nutritive or biometric parameters and nutrient retention when compared with the control diet. However, higher levels of red beet and betaine had negative effects on growth and nutritive parameters. The tested ingredients enhanced quality parameters regardless of the concentration used. After feeding the red beet and betaine, fish flesh showed lower water activity and better textural and colour properties than the control and also a dose-dependent effect on lipid oxidation was observed.This work has been co-funded with FEDER and INIA funds. Julia Pinedo has been granted with the FPI-INIA grant number 21 [call 2012, BOE-2012-13337].Pinedo-Gil, J.; Tomas-Vidal, A.; Jover Cerda, M.; Tomás-Almenar, C.; Sanz-Calvo, MÁ.; Martín-Diana, AB. (2017). Red beet and betaine as ingredients in diets of rainbow trout (Oncorhynchus mykiss): effects on growth performance, nutrient retention and flesh quality. Archives of Animal Nutrition. 71(6):486-505. doi:10.1080/1745039X.2017.1391503S48650571

Enhancement of quality of rainbow trout (Oncorhynchus mykiss) flesh incorporating barley on diet without negative effect on rearing parameters

[EN] Barley concentrations ranging from 0 to 32% (0B, 40B, 80B, 160B, and 319B) were incorporated into rainbow trout, Oncorhynchus mykiss (Walbaum) diets. The experiment started with an initial average fish weight of 127.72 +/- 5.65 g and finished when they reached commercial weight (final weight between 312 and 330 g) after 84 days. The inclusion of barley in the diets did not show a significant effect on growth and biometric parameters, fat and carbohydrate digestibilities; however, protein digestibility decreased significantly with the incorporation of barley on diets. Glucose levels increased significantly with barley concentration in the diet, and lactate and cortisol levels were also significantly affected after a stress period regardless of the diet. Meat quality was influenced as well by barley concentration. Lower water activity values and an enhancement in textural and color properties were observed in fish fed with the diet containing the highest barley concentration. Trout fed feed with higher concentrations of barley (160B) showed lower lipid oxidation levels than those fed with lower concentrations (control and 40B). The sensory panel found that fish fed with diets higher than 8% in barley content (80B) exhibited a brighter red color in the gills and a better texture; also, meat color became redder with a higher barley inclusion (160B and 319B), being all these sensory parameters correlated with fish freshness. Thus, results indicate that barley can be substituted for wheat fraction without any detrimental effect on production efficiency and enhancing fish quality.This work has been co-funded with FEDER and INIA funds. The authors thanks Dr. Francisco Ciudad Bautista for providing barley variety obtained in ITACyL, IRTA, EEDF-CSIC, ITAP, and INIA (1FD97-0792 and RTA2006-00020-C04). Julia Pinedo has been granted with the FPI-INIA grant number 21 (call 2012, BOE-2012-13337).Pinedo-Gil, J.; Tomas-Vidal, A.; Larrán-García, AM.; Tomas-Almenar, C.; Jover Cerda, M.; Sanz-Calvo, M.; Martín-Diana, A. (2017). Enhancement of quality of rainbow trout (Oncorhynchus mykiss) flesh incorporating barley on diet without negative effect on rearing parameters. Aquaculture International. 25(3):1005-1023. https://doi.org/10.1007/s10499-016-0091-010051023253A.O.A.C., Association of Official Analytical Chemists (1990) Official methods of analysis, 15th edn. Association of Official Analytical Chemists, Arlington 1298 ppAi Q, Mai K, Zhang L, Tan B, Zhang W, Xu W, Li H (2007) Effects of dietary β-1,3- glucan on innate immune response on large yellow croaker, Pseudosciaena crocea. Fish Shellfish Immun 22:394–402APROMAR 2014 La acuicultura en España 2013. Report by the Spanish Association of marine Aquaculture (APROMAR) and the Spanish Association of Freshwater Aquaculture (ESCUA). 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Effect of red beet and betaine modulating oxidation and bioactivity of rainbow trout

[EN] The present study compares a control diet to four experimental diets, in which two red beet (14% and 28%) and two betaine levels (0.9% and 1.63%) were incorporated in rainbow trout diets according to a factorial design. The effects of the inclusion of different red beet and betaine concentrations on fatty acid (FA) profile, lipid peroxidation, and antioxidant activity on rainbow trout fillets were investigated. Although no significant differences were observed with the control group, results indicated that red beet and betaine improved fish fillet FA profile, producing an increase in polyunsaturated FAs, mainly docosahexaenoic acid. Higher red beet and betaine concentrations increased flavonoid and phenolic content in the diets; however, no effects were observed for the antioxidant properties of rainbow trout fillets.This work was carried out with funding from INIA and ITACyL, and cofounded by FEDER funds. Julia Pinedo has been granted with the FPI-INIA grant number 21 (call 2012, BOE-2012-13337).Pinedo-Gil, J.; Tomas-Vidal, A.; Rico-Barges, D.; Tiwari B.K.; Alvarez-García C; Jover Cerda, M.; Sanz-Calvo MA... (2019). Effect of red beet and betaine modulating oxidation and bioactivity of rainbow trout. Journal of Aquatic Food Product Technology. 38-48. https://doi.org/10.1080/10498850.2018.1560381S384

Effects on Lipid Oxidation and Bioactive Properties of Rainbow Trout Fillets Fed with Barley

[EN] Barley concentrations ranging from 0% to 32% were incorporated into rainbow trout (Oncorhynchus mykiss) diets. The effect of barley concentration on lipid peroxidation and antioxidant activity of fish fillets were analyzed. Results showed that the inclusion of barley in rainbow trout diets had an inhibitory effect on lipid oxidation, probably associated with certain bioactive compounds in barley that could interact with scavenging and reducing metabolites involved in lipid oxidation. Concentrations up to 8% of barley produced fish fillets with high antioxidant activity and higher levels of alpha-tocopherol.This work was carried out with fundings from INIA and ITACyL and cofounded by FEDER funds. Julia Pinedo has been granted with the FPI-INIA grant number 21 [call 2012, BOE-2012-13337].Pinedo-Gil, J.; Tomas-Vidal, A.; Rico, D.; Tiwaric, B.; Álvarez García, C.; Jover Cerda, M.; Sanz-Calvo, MÁ.... (2019). Effects on Lipid Oxidation and Bioactive Properties of Rainbow Trout Fillets Fed with Barley. Journal of Aquatic Food Product Technology. 28(5):495-504. https://doi.org/10.1080/10498850.2019.1604596S49550428

Effect of Barley on Liver Histology of Rainbow Trout, Oncorhynchus mykiss

[EN] This study investigated the effects of the incorporation of barley instead of wheat to study fish growth and biometrics parameters, body composition, retention efficiency and liver histology of rainbow trout Oncorhynchus mykiss. Experimental diets were used containing different barley concentrations (0-16%) randomly assigned to four groups per treatment. Results showed a significant change on liver histological parameters. Liver cell vacuolization was significantly lower on fish fed with 16B diets compared to control diet and revealed some degeneration. Those fish also showed more regular hepatocytes than in control diet.This work has been co-funded with FEDER and INIA funds (call 2012, BOE-2012-13337).Pinedo-Gil, J.; Martín-Diana, AB.; Caballero-Cansino, MJ.; Sanz-Calvo, MÁ.; Jover Cerda, M.; Tomas-Vidal, A. (2017). Effect of Barley on Liver Histology of Rainbow Trout, Oncorhynchus mykiss. Journal of Aquaculture & Marine Biology. 5(3). https://doi.org/10.15406/jamb.2017.05.00123S5

Efecto de la cebada en dietas de trucha arcoiris (Oncorhynchus Mykiss) y estudio de su impacto en los índices productivos y de calidad de la carne

Pinedo Gil, J. (2014). Efecto de la cebada en dietas de trucha arcoiris (Oncorhynchus Mykiss) y estudio de su impacto en los índices productivos y de calidad de la carne. http://hdl.handle.net/10251/54790Archivo delegad

Study of novel carbohydrate sources on rainbow trout (Oncorhynchus mykiss) diets

Tesis por compendioEn 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/10251/107364TESISCompendi