Michael López-Herrera

Current strategies in animal nutrition aim to reduce reliance on conventional protein sources by promoting locally available and sustainable alternatives. Retama monosperma (L.) Boiss, an endemic shrub of the Iberian Peninsula and Morocco that is adapted to harsh dune environments, has been identified as a potential novel protein feed. However, its seeds contain high levels of quinolizidine alkaloids (QA), which may limit their nutritional use. The objective of this study was to evaluate the in vivo effects of partially replacing 20% or 80% of peas with raw or heat-treated R. monosperma seeds in goat diets on feed intake, nutrient digestibility, nitrogen and energy utilization, ruminal fermentation, microbial protein synthesis, and animal health. Additionally, various aqueous-thermal treatments were evaluated to reduce QA content, with the most effective method selected for the feeding trial. The seeds showed a total QA concentration of 27,189 mg/kg, with cytisine accounting for 99.2% of the total alkaloids, along with minor amounts of N-methylcytisine and anagyrine. Detoxification efficiency varied among treatments, achieving QA reductions from 55.7% to 95.4%. In vivo results indicated that inclusion of R. monosperma seeds modified ruminal fermentation, increasing ammonia concentration and urinary purine derivatives, suggesting enhanced protein degradability and microbial protein synthesis. Despite these changes, no negative effects were observed on feed intake, apparent nutrient digestibility, nitrogen balance, or blood metabolic parameters. In conclusion, partial replacement of conventional protein sources with raw or heat-treated R. monosperma seeds appears feasible in moderate goat production systems without compromising animal performance or health.

Global demand for animal protein necessitates sustainable alternatives to soybean meal (SBM). This systematic review evaluated 177 peer-reviewed articles (2002–2023) across 12 categories to analyse the nutritional value of alternative protein sources for ruminant diets and to assess the associated environmental trade-offs. This was achieved through a targeted review, synthesising data from Life Cycle Assessments (LCAs) to create a multi-criteria matrix for ranking sustainability profiles. Results indicate that microalgae, insects, and single-cell proteins exhibit crude protein levels comparable to SBM. Moreover, insects, seaweeds, and animal by-products (ABPs) often present superior essential amino acid profiles and high intestinal digestibility. From an environmental perspective, insects, seaweeds and microalgae offer excellent land-use efficiency and significant enteric methane mitigation (17–74.6%), though current economic viability is hindered by high processing costs and emerging supply chains. Conversely, ABPs and agro-industrial by-products effectively embody circular economy principles, enhancing local system resilience. Ultimately, replacing SBM requires a multi-objective approach through a functional hybridisation model, carefully balancing metabolic efficiency with environmental sustainability. While microalgae, insects, and seaweeds demonstrate promising nutritional and mitigation potential, addressing economic barriers and ensuring biosecurity seems essential. Future LCA frameworks should prioritise bioavailable nutrient metrics to optimise the environmental impact of ruminant production.

Improving strategies against obesity and overweight requires estimating and constantly monitoring health risk factors. This study aimed to: (1) develop multiple linear regression (MLR) models predicting adult overweight and obesity prevalence in within‐country analysis, based on FAO food balance sheets, and (2) assess the evolution of food groups and the estimated adult overweight and obesity prevalences over recent decades in Spain as a case study, as well as analyzing their projections into the long‐term future by using three different FAO scenarios. The obtained MLR models showed high accuracy and predictive capability, and they would help to monitor these target health outcome variables in within‐country analysis. The evolution of whole consumption of food groups in Spain showed small or moderate variations from 2000 to the present. However, adherence to the traditional and healthy Mediterranean diet of the Spanish population decreased. Overweight and obesity prevalences in Spain, estimated by MLR, showed a downward trend or remained similar in the last decade. This was consistent with prevalence projections for 2050 in Spain according to the FAO Toward Sustainability scenario, predicting a decrease in the consumption of commodities supplying energy and protein per capita, and more aligned with current food‐based dietary guidelines in Spain. It will be necessary to assess whether this trend remains stable over time and whether it is the result of the changes in dietary patterns and lifestyles promoted by sectors involved in public health.

Introduction. Forages in the tropics have low digestibility, which is why alternative feed option such as Tithonia diversifolia (Hemsl.) are sought to improve the quality of the offered diet. Objective. To evaluate the effect of fertilizer type and the regrowth age of Tithonia diversifolia forage on rumimal parameters. Materials and methods. The study was conducted in 2020 at the Santa Lucía Experimental Farm of the Universidad Nacional, Costa Rica. A completely randomized split-plot design was used with fertilizer type as the main plot and regrowth age as subplot, with three replications per treatment. The fertilizer types were: vermicompost (L), chemical (Q), and control (C) without fertilizer use. The evaluated regrowth ages were 30, 50, and 70 days, resulting in a total of nine treatments. The variables assessed were: in situ dry matter degradability kinetics (DISMS), pH, ammoniacal nitrogen (NH3), in vitro gas, and methane production (CH4). An ANOVA was carried out for divided plots. Results. The highest DISMS was found in C30 (92.84 %) and the lowest in Q70 (64.21 %). The type of fertilization influenced NH3 contents, with the highest value observed in chemical fertilizer treatments (275.88 mg NH3/L rumen fluid). C70 produced the highest amount of gas (79.59 mL/g), whereas Q30 had the lowest average (28.38 mL/g). Methane production did not show significant differences, with values ranging from 3.42 to 8.67 mL CH4/g DM. Conclusion. Fertilization and regrowth age modified in situ and in vitro ruminal parameters. The obtained results suggest that this forage resource can be considered a supplement to grazing grasses in the tropics, where positive effects are generated on DM digestibility, gas, and CH4 production.

Introduction. Tithonia diversifolia (Hemsl.) A. Gray is a plant with high potential for ruminant feeding, but there is limited research comparing the effects of chemical or organic fertilization at different regrowth ages on its yield and nutritional composition. Objective. To evaluate the effect of the type of fertilizer and the age of regrowth on the yield and nutritional composition of Tithonia diversifolia forage. Materials and methods. The work was conducted in 2020 at the Finca Experimental Santa Lucía of the Universidad Nacional de Costa Rica. A completely randomized divided plot design was employed, with fertilizer type as the main plot and regrowth age as the subplot, with three replicates per treatment. The fertilizer types tested were vermicompost, urea, and a control without fertilizer, with a nitrogen application rate of 150 kg/ha/year. The regrowth ages evaluated were 30, 50, and 70 days for a total of nine treatments. The variables evaluated were biomass production, leaf/stem relation, and nutritional composition. A split plot ANOVA was performed to analyze the data. Results. Among the treatments, the urea treatment with 70 days of regrowth exhibited the highest biomass production (77.18 t/ha of green matter and 7.10 t/ha of dry matter [MS]), while the control treatment with 30 days of regrowth yielded the highest leaf/stem relation (1.77). The type of fertilizer had a significant effect on the variables of MS, crude protein (PC), neutral detergent fiber, and non-fibrous carbohydrates (CNF), whereas regrowth age alone did not significantly affect digestible neutral detergent fiber and CNF. The highest PC content was observed in the urea treatment with 30 days of regrowth (27.61 % PC). Conclusion. Fertilization and regrowth age influenced the yield and bromatological composition of T. diversifolia. These findings contribute to our understanding of optimizing T. diversifolia production for ruminant feeding.

Introducción. Tithonia diversifolia es una planta con alto potencial para la alimentación de rumiantes, pero no existen estudios que comparen el efecto de la fertilización química u orgánica a diferentes edades de rebrote sobre su rendimiento y composición bromatológica. Objetivo. Evaluar el efecto del tipo de fertilizante y la edad de rebrote sobre rendimiento y composición bromatológica del forraje de Tithonia diversifolia. Materiales y métodos. El trabajo se realizó entre los años 2020 y 2021 en la Finca Experimental Santa Lucía de la Universidad Nacional Costa Rica. Se utilizó un diseño de parcelas divididas completamente al azar: tipo de fertilización (parcela) y edad de rebrote (subparcela) con 3 repeticiones por tratamiento. Los tipos de fertilizante fueron: lombricompost (L), químico (Q) y un control (C) sin uso de fertilizante. Las edades de rebrote evaluadas fueron 30, 50 y 70 días para un total de 9 tratamientos. Las variables evaluadas fueron: producción de biomasa, relación hoja/tallo y composición bromatológica. Para el análisis de los datos se utilizó un ANOVA para parcelas divididas. Resultados. El tratamiento Q70 fue el que alcanzó la mayor producción de biomasa (77,18 t/ha de materia verde (MV) y 7,10 t/ha MS), la mayor relación hoja/tallo (1,77) se obtuvo en C30. El tipo de fertilizante tuvo un efecto significativo sobre las variables de MS, PC, FDN y CNF, mientras que la edad de rebrote sólo no generó efectos significativos sobre las variables dFDN y CNF. El mayor contenido de proteína se encontró en Q30 (27,61 % MS). Los contenidos de FDN oscilaron entre 30,23 y 46,29 % y la ENL entre 1,34 y 1,42 Mcal/kg MS. Conclusión. La fertilización y la edad de rebrote demostraron influir sobre el rendimiento y la composición bromatológica de la T. diversifolia, encontrando una respuesta inmediata a la fertilización química.

El objetivo de este estudio fue determinar las características nutricionales de mezclas frescas y ensiladas, elaboradas a partir de leguminosas y cuatro fuentes de carbohidratos. El experimento fue realizado entre los años 2015 y 2016. Se utilizó un diseño factorial al azar, donde se combinaron cuatro especies de leguminosas (Vigna unguiculata, Arachis pintoi, Cratylia argentea, Erythrina poeppigiana) y cuatro fuentes de carbohidratos (melaza de caña de azúcar, pulpa de cítricos deshidratada, maíz molido y fruto inmaduro de guineo cuadrado), para un total de 16 tratamientos. Los forrajes fueron picados y colocados en bolsas de empaque al vacío durante 50 días. A todos los tratamientos se les agregó inóculo bacterial artesanal (1 L/ton), y fueron repetidos 4 veces. La bromatología de los ensilados fue influenciada por el efecto de la especie leguminosa y de la fuente de carbohidratos. El contenido de materia seca de los ensilados fue menor a 23%, siendo los ensilados de arbóreas los de mayor promedio (19,9%) en comparación con las leguminosas herbáceas (12,6%). La proteína cruda mostró valores entre el 13,9-19,4% en los diferentes tratamientos; los carbohidratos no fibrosos presentaron una concentración entre 23,1-37,5%; la fibra en detergente ácido fluctuó entre 21,6-38,2%; y el total de nutrientes digestibles mostró un intervalo entre 58,3-66,1%. Los ensilados de Cratylia son los materiales que, por su contenido de nutrientes, muestran mayor aporte de proteína bruta, aunque son los de menor contenido energético sin importar el tipo de carbohidrato que se utilice. Por otra parte, el maíz molido fue la fuente de carbohidratos que más cambios provocó en los ensilados, ya que aumentó los valores de materia seca, carbohidratos no fibrosos y energía.

El objetivo de esta investigación fue determinar el efecto de la inclusión de Tithonia diversifolia sobre las características físicas, fermentativas y nutricionales de los ensilados de pasto Cuba OM22 con guineo cuadrado. El estudio se llevó a cabo entre setiembre del 2020 y julio del 2021. Se utilizó un diseño irrestricto completamente al azar donde se mezclaron pasto Cuba OM22 con botón de oro (Tithonia diversifolia) en las proporciones porcentuales 0:100, 25:75, 50:50, 75:25 y 100:0. A estas mezclas proporcionadas se les agregó 10% de Musa sp. y 5% de melaza en base fresca. El ensilaje se desarrolló en microsilos de bolsa plástica de 5 kg con cierre hermético durante 60 días. Se encontró que el forraje de T. diversifolia afecta las características físicas de los ensilados, sobre todo en color y textura; mientras que el pH no fue diferente entre los tratamientos. La concentración de materia seca disminuyó al igual que la fibra detergente neutro (FDN) y la fibra detergente neutro digestible (dFDN). Por otra parte, la T. diversifolia aumentó los contenidos de proteína Cruda (PC) y carbohidratos no fibrosos (CNF). El incremento encontrado fue de 0,5 puntos porcentuales en la PC, en los CNF el aumento fue de 4,25 puntos porcentuales y la FDN se redujo a razón de 5 puntos. En todos los casos, por cada incremento de 25% en la inclusión de T. diversifolia; estos efectos se reflejaron en un aumento de la cantidad de nutrientes digestibles de los ensilados. En conclusión, la inclusión de T. diversifolia permitió mejorar la calidad nutricional de los ensilados sin afectar el proceso fermentativo, aunque su calidad física sí pudo verse afectada debido a la mayor humedad que posee el forraje de esta arbustiva.