<p dir="ltr">Maximizing growth performance in swine production, in the face of larger litter sizes and potential milk limitations, is crucial. This thesis explores the impact of various nutritional strategies, including creep feeding, dietary sweeteners, glutamine supplementation, sensory additives, and low crude protein diets on piglet lactation and nursery growth performance. Data in this thesis were analyzed using the GLM procedure in SAS 9.4. In the first study (Chapter 2), fifty-one sows and their litters (17/creep treatment) were used to evaluate the effects of creep feeding and nursery diets on piglet growth. Ten days prior to weaning, litters were assigned to three treatments: control creep feed (CF-CON), CON + garlic-based flavoring (50 ppm Allium XL; CF-ALL-XL), and no creep feed (NO-CF). Post-weaning, 506 pigs were allotted to either control (CON) or flavored (ALL-XL) nursery diets in a 3x2 factorial design with 10 pens/treatment, each containing 7 or 8 pigs. Nursery dietary treatments were fed in phases 1 and 2, followed by common phase 3 and 4 diets. Weekly body weights (BW) and feed intake were recorded to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). Creep feeding treatment during lactation did not affect litter or piglet BW gain pre-weaning. ALL-XL did not affect total creep feed intake (CON=114 g/pig vs. ALL-XL=110 g/pig). Providing CF-CON or CF-ALL-XL during lactation increased ADFI on d 2, 3, and 4 post-weaning (P<0.013). Pigs fed either CF-CON or CF-ALL-XL increased week 1 nursery ADFI (8.8%; P<0.02), numerically increased ADG (5.2%), and greater d7 BW (P=0.055). Overall (d0-35), pigs fed CF-CON had greater ADG (P<0.05) and ADFI (P<0.05) than CF-ALL-XL with No-CF pigs being intermediate in ADG and greater ADFI (P<0.05) than CF-ALL-XL fed pigs. Final BW (P<0.05) was greater for CF-CON fed pigs than CF-ALL-XL fed pigs with No-CF pigs being intermediate (23.5 kg, 23.0 kg, 23.3 kg, respectively). Nursery dietary flavoring treatment (CON vs ALL-XL) did not affect post-weaning ADG, ADFI, or G:F at any point during the study (P>0.12). In the second study (Chapter 3), fifty-seven sows and their litters were used to test the effects of creep feed and a dietary sweetener (Taktik) on piglet lactation and nursery performance in low lactose diets. Six days prior to weaning, litters were assigned to either control creep feed (CF-CON), control + sweetener (50 ppm Taktik; CF-TAK), or no creep (No-CF). Post-weaning, 550 pigs were assigned to control (CON) or sweetened (Taktik, 50 ppm; TAK) nursery diets in a 3x2 factorial design with 10 nursery pens per treatment, each containing 9 or 10 pigs. There were no significant differences in litter weight, weight gain, or piglet weight during lactation due to CF treatment. However, CF-CON pigs tended to have higher litter feed intake (P=0.060) and ADFI per pig (P=0.059) during lactation. During the first week post-weaning, CF-CON pigs had higher ADFI (P<0.05), ADG (P<0.05), and d7 BW compared to CF-Tak pigs and No-CF pigs. During d 6-14 CF-CON pigs had greater ADG (P<0.05) and ADFI (P<0.05) than CF-Tak pigs and the No-CF pigs tended (P<0.10) to also have greater ADFI than CF-Tak pigs. Overall (d0-34), CF-CON pigs had higher ADG and ADFI compared to CF-Tak pigs (P<0.05) and No-CF pigs tended (P<0.10) to have greater ADG than CF-Tak pigs. There were no significant differences (P>0.15) in ADG, ADFI, or G:F between CON and TAK nursery diet treatments. In the third study (chapter 4), thirty-one sows and their litters were utilized to test the effects creep feed and nursery diets supplemented with or without glutamine on lactation and nursery performance as well as creep feeder type impacts. During lactation there were three dietary treatments: control creep feed (CF-CON), control creep feed + glutamine (0.40%; CF-GLUT), or no creep feed (No-CF). There were two creep feeder types: plastic (PLAST) or stainless steel (SS), that were evenly distributed between the creep feed treatments. Post-weaning 270 pigs were allotted to either control (CON) or control + glutamine (0.40%; GLUT) nursery diets with pigs previously given or not glutamine creep feed continuing to receive similar glutamine treatment in the nursery period and the No-CF pigs being evenly split to CON and GLUT nursery diets. Litter weights and creep feed intake were recorded on d -7 and 0 (weaning). During nursery there were 7 pens/treatment with 6 or 7 pigs/pen, blocked by initial BW within creep treatment. Neither glutamine creep feeding treatments affected litter or piglet weaning weights (P>0.24). Pigs given creep feed during lactation had increased ADFI during the first week post-weaning (P<0.03) but did not result in greater overall nursery growth performance. The inclusion of glutamine in creep feed or nursery diets did not improve growth performance at any point during the study. In the fourth study (chapter 5), 416 weanling pigs were used to test the effects of a sensory feed additive (SA; Luctamax) on control (CON) and low crude protein (LCP) nursery diets in a 2x2 factorial design (CON, CON+SA, LCP, LCP+SA) with 15 replicate pens of 6 or 7 pigs/pen. Decreased dietary CP (4%) was achieved by removing or decreasing fish meal and soy concentrate in phases 1 and 2 and reducing soybean meal in phase 3 and adding synthetic amino acids to maintain amino acid ratios (NRC 2012). The SA was included at 0.1% in Phase 1 and 2 diets and 0.05% in Phase 3 diets. During PH1 (d 0-7) pigs receiving the CON diets tended (P=0.065) to have a higher G:F compared to pigs receiving LCP diets. For the remainder of this study there were consistent interactions between dietary CP and SA. When SA was added to the LCP diet ADFI slightly increased but when SA was added to CON diet ADFI decreased and these changes in feed intake often led to similar dietary interactions in ADG. During PH2 (d 7-21), pigs fed CON or LCP+SA diets had higher ADFI (P=0.032) and tended to have a higher ADG (P=0.094) but reduced G:F (P=0.100) compared to pigs fed CON+SA or LCP diets. In PH3 (d 21-36), pigs fed CON or LCP+SA diets had a higher ADG (P=0.027) and ADFI (P=0.011) compared to CON+SA or LCP diets. During PH3 pigs fed LCP diets had higher ADFI (P<0.001) but reduced G:F (P<0.0001) than pigs fed CON diets. Overall (d0-36), pigs fed CON or LCP+SA diets had higher ADFI (P=0.016) and tended to have a higher ADG (P=0.059) but reduced G:F (P=0.067) compared to pigs fed CON+SA or LCP diets. For the entire nursery period, pigs fed CON diets had a higher G:F (P<0.001) compared to pigs fed LCP diets, while LCP pigs tended to have a higher ADFI (P=0.054) compared to CON pigs. Feeding LCP diets during PH2 decreased feed costs/kg of gain but feed cost were increased (P<0.0001) during PH3 when LCP diets were fed compared to CON diets. These studies highlight the potential benefits and limitations of various nutritional strategies in enhancing piglet growth performance. Creep feeding, dietary sweeteners, glutamine supplementation, sensory additives, and low crude protein diets can potentially influence post-weaning performance, but their effectiveness depends on specific conditions and formulations. Further research is needed to optimize these strategies for improved swine production efficiency.</p>

[ES] La acuicultura es una de las principales actividades en el ámbito de la producción animal. Su progreso está delimitado por la dependencia de materias primas de origen tanto marino como terrestre, ambas necesarias para la elaboración de piensos destinados a la alimentación de las especies en cultivo. La introducción de nuevas materias primas o sustancias destinadas a la mejora de la fisiología de la especie (piensos funcionales) puede comprometer la palatabilidad de los piensos, su consumo y por extensión el crecimiento de los animales. El objetivo principal de esta tesis fue encontrar aditivos sensoriales (saborizantes) que puedan sobrepasar los efectos negativos sobre la palatabilidad de los piensos inducidos por la inclusión de materias vegetales en la elaboración de los piensos para cultivo de la dorada (Sparus aurata). Para ello, evaluamos la funcionalidad de los sistemas de auto-demanda en el estudio del comportamiento alimenticio de esta especie, profundizando en su posible utilidad en la discriminación sensorial/gustativa de los piensos. Evaluamos el efecto de estrógenos y andrógenos no aromatizables sobre la ingesta como posibles factores anti-nutricionales presentes en los piensos de sustitución. Estudiamos el efecto de dos saborizantes sobre la ingesta y dinámica de crecimiento de la dorada y finalmente estudiamos el posible efecto de estos sobre la anorexia inducida por el estrés. Los resultados demuestran que la dorada se adapta bien a los sistemas de auto-demanda y estos pueden ser utilizados para el estudio de su comportamiento alimenticio. Utilizando estos sistemas hemos demostrado que la dorada puede discriminar entre diferentes piensos en función de la presencia de elementos fuertemente amargos o de elementos saborizantes que pueden además ayudar a sobrepasar los efectos negativos del estrés sobre la ingesta. Finalmente, demostramos que esta especie es especialmente sensible a la presencia de estrógenos o andrógenos no aromatizables en la composición del pienso sugiriendo que los elementos estrogénicos o androgénicos pueden actuar como elementos anti-nutricionales. / [CA] L'aqüicultura és una de les principals activitats en l'àmbit de la producció animal. El seu progrés està delimitat per la dependència de matèries primeres d'origen tant marí com terrestre, totes dues necessàries per a l'elaboració de pinsos destinats a l'alimentació de les espècies en cultiu. La introducció de noves matèries primeres o substàncies destinades a la millora de la fisiologia de l'espècie (pinsos funcionals) pot comprometre la palatabilitat dels pinsos, el seu consum i per extensió el creixement dels animals. L'objectiu principal d'aquesta tesi va ser trobar additius sensorials (saboritzants) que puguen sobrepassar els efectes negatius sobre la palatabilitat dels pinsos induïts per la inclusió de matèries vegetals en l'elaboració dels pinsos per a cultiu de l'orada (Sparus aurata). Per això, avaluem la funcionalitat dels sistemes d'auto-demanda en l'estudi del comportament alimentari d'aquesta espècie, aprofundint en la seua possible utilitat en la discriminació sensorial/gustativa dels pinsos. Avaluem l'efecte d'estrògens i andrògens no aromatizables sobre la ingesta com a possibles factors anti-nutricionals presents en els pinsos de substitució. Estudiem l'efecte de dos saboritzants sobre la ingesta i dinàmica de creixement de l'orada i finalment estudiem el possible efecte d'aquests sobre l'anorèxia induïda per l'estrés. Els resultats demostren que l'orada s'adapta bé als sistemes d'auto-demanda i aquests poden ser utilitzats per a l'estudi del seu comportament alimentari. Utilitzant aquests sistemes hem demostrat que l'orada pot discriminar entre diferents pinsos en funció de la presència d'elements fortament amargs o d'elements saboritzants que poden a més ajudar a sobrepassar els efectes negatius de l'estrés sobre la ingesta. Finalment, vam demostrar que aquesta espècie és especialment sensible a la presència d'estrògens o andrògens no aromatizables en la composició del pinso suggerint que els elements estrogènics o androgènics poden actuar com a elements anti-nutricionals. / [EN] Aquaculture is one of the main activities within the animal production. Its progress is constricted by the dependency raw materials with marine and terrestrial origin both critical for the production of feed diets for cultured species. The incorporation of new raw materials or functional substances driven to the improvement of animal physiology (functional feed) can compromise the palatability of diets, consumption and by extension animal growth. The main issue of this thesis was to find sensorial enhancers that can overcome the negative effects on diet palatability induced by the inclusion of vegetal rows in the elaboration of feed for seabream culture (Sparus aurata). To that end we test the functionality of self-feeding systems in the study of feeding behaviour of this species deepening in the study of sensory/gustatory feed discrimination. We also evaluate the effect of both oestrogens and no-aromatized androgen on food intake as potential anti-nutritionals included in the substitution diets. In addition, we studied the effect of flavourings on seabream feeding behaviour and growth performance and finally we studied the potential effect on stress-induced anorexia. Results demonstrated that seabream adapts perfectly to self-feeding systems that can be used for the study its feeding behaviour. Using self-feeding systems, we have also demonstrated that seabream can discriminate between different diets by association to potent sour deterrents of flavourings that can help to overcome the negative effects of stress on feeding behaviour. Finally, we demonstrate that seabream is especially sensible to the presence of oestrogen or androgens in the diet compositing suggesting its potential role as anti-nutritional elements. / Puchol Soriano, S. (2022). Regulación temporal y sensorial de la ingesta en la dorada (Sparus aurata) [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/181576