Dario Vallejo-Timarán

The bovine cervix undergoes endocrine-dependent physiological changes that may influence local immune activity and complicate the interpretation of cervical inflammation. This study evaluated the relationships among macroscopic cervical appearance, cervical neutrophil infiltration, reproductive stage, and endometrial inflammation in postpartum grazing dairy cows. Non-pregnant lactating Holstein × Jersey crossbred cows (n = 80) ≥ 45 days in milk underwent reproductive examination, cervical video-endoscopy, ultrasonography, cervical and endometrial cytology, and serum progesterone determination. Macroscopic cervical appearance was classified as C0, C1, or C2, whereas cervical polymorphonuclear neutrophil (PMN) percentage was analyzed as the primary proportional outcome using adjusted fractional logistic regression. A ≥5% cervical PMN threshold was used operationally for secondary analyses. C0, C1, and C2 occurred in 30.0%, 50.0%, and 20.0% of cows, respectively, and 20.0% had cervical PMN ≥ 5%. Macroscopic cervical appearance was not associated with cervical PMN percentage (p = 0.931) or cervical PMN ≥ 5% (p = 1.000). Cervical PMN percentage was higher in follicular-stage than in luteal-stage cows (p < 0.001). This association persisted after adjustment for parity and cytological endometritis using fractional logistic regression (β = 2.42; 95% CI, 0.81–4.03; p = 0.003), with an adjusted marginal difference of 10.48 percentage points (95% CI, 1.42–19.54; p = 0.023). A complementary two-part analysis supported this association, showing higher odds of detectable cervical PMNs (OR = 4.71; 95% CI, 1.73–12.82; p = 0.002) and higher mean PMN proportions among positive observations (mean ratio = 4.11; 95% CI, 1.40–12.06; p = 0.010) during the follicular stage. In secondary Firth penalized logistic regression, follicular stage remained associated with cervical PMN ≥ 5% (aOR = 5.38; 95% CI, 1.39–20.83; p = 0.015). Cervical and endometrial PMN percentages were weakly positively correlated (ρ = 0.240; p = 0.033), while agreement between cervical PMN ≥ 5% and cytological endometritis was limited (κ = 0.258). Neither cervical neutrophil infiltration nor cytological endometritis was associated with subsequent pregnancy, whereas serum progesterone concentration showed a positive exploratory association with pregnancy. Cervical neutrophil infiltration is associated with reproductive stage independently of parity and cytological endometritis, without relying on an unvalidated diagnostic threshold. Cervical cytology should therefore be interpreted within the reproductive and physiological context of the cow.

Musical exposure in dairy cattle has been associated with potential effects on milk production, behavior, and physiological regulation; however, available evidence remains heterogeneous and potentially affected by biological and environmental confounding. In high-tropical grazing systems, these responses are simultaneously influenced by stress physiology, disease, nutrition, management, climatic variability, and individual adaptation. This review integrated causal inference and graphical epidemiology to develop biologically grounded directed acyclic graphs (DAGs) representing hypothesized causal pathways between musical exposure and milk production, behavior, and heart rate variability (HRV). An analytical narrative synthesis of physiological, ethological, autonomic, and epidemiological evidence was conducted, and three independent DAGs were constructed using DAGitty version 3.1. Variables were classified according to their epidemiological roles. The production DAG identified stress as a major integrative node linking disease, nutrition, reproductive physiology, management, and milk yield. The behavioral DAG highlighted the roles of ecological organization, resource access, social interaction, and environmental instability. The HRV DAG treated HRV as beat-to-beat variation in cardiac intervals that provides a non-invasive index of autonomic nervous system (ANS) modulation, including sympathetic and parasympathetic influences, and indicated that responses may occur through indirect modulation of stress physiology and vagal activity. We conclude that musical interventions should be interpreted as context-dependent sensory exposures rather than isolated causal determinants; the proposed DAGs provide an explicit basis for selecting covariates, avoiding inappropriate adjustment, and designing future studies of dairy cattle welfare and production.

En el norte de Nariño, Colombia, territorio cuya historia campesina se encuentra estrechamente vinculada con la diversidad agrícola, surge esta experiencia de construcción colectiva a partir del enfoque agroecológico. El presente libro documenta el proceso participativo desarrollado con familias campesinas del municipio de Colón Génova, en el contexto de la propuesta de constitución de la zona de reserva campesina y de los territorios campesinos agroalimentarios. Mediante el diálogo de saberes entre productores, comunidades, instituciones educativas y AGROSAVIA, se construyeron herramientas orientadas a comprender las dinámicas territoriales, fortalecer la soberanía alimentaria y diseñar estrategias adaptadas a las condiciones locales y que se integran al sistema productivo cafetero. Esta obra presenta diagnósticos participativos, análisis de biodiversidad, evaluación de sistemas alimentarios, planificación predial y los resultados de la implementación de huertos multifuncionales integrados con especies menores. Más allá de los indicadores técnicos, recoge las voces, los conocimientos y el aprendizaje de las familias campesinas que continúan apostándole a sistemas productivos más resilientes, diversos y autónomos. Esta experiencia ofrece herramientas y reflexiones para productores, investigadores, organizaciones y tomadores de decisiones interesados en impulsar procesos de transición agroecológica con enfoque territorial.

Fresh vegetables cultivated in small-scale household systems may facilitate the transmission of foodborne parasitic structures due to environmental exposure and inconsistent hygienic conditions. This study identified the presence, prevalence, and distribution of enteric parasitic structures in vegetables and soils from family farming systems undergoing an agroecological transition process in the Colón–Génova subregion, Colombia, and characterized the biosecurity measures employed by producers. Standard parasitological methods were used to analyze vegetable samples ( n = 216) from six horticultural species and farm soil samples. Strongyle-type eggs (order Strongylida), larvae morphologically compatible with intestinal nematodes, Entamoeba coli , and E. histolytica/dispar -like cysts were detected with varying frequencies, primarily in broad-leaved vegetables such as lettuce, cabbage, and Swiss chard. Soil samples also contained viable parasitic structures compatible with environmental contamination, suggesting that soil may function as a potential environmental source of contamination. The biosecurity assessment indicated an intermediate level of compliance, with critical deficiencies related to disinfection of tools and footwear, incomplete composting of organic fertilizers, and inadequate exclusion of domestic animals from cultivation areas. These results demonstrate that household gardens may harbor enteric parasitic structures of public health relevance. These findings highlight the need to strengthen hygiene protocols, improve the management of organic amendments and water sources, and adopt One Health-based preventive strategies to reduce contamination risk in small-scale horticultural systems.

The guinea pig, Cavia porcellus, is a key mammal in rural areas of some Andean countries, such as Colombia, where it serves as an important source of food with high nutritional value, thereby strengthening food security and improving rural quality of life. This study aimed to establish the prevalence of pneumonic patterns in weaning guinea pigs in the region of Pasto (Nariño), Colombia, the disease spatial distribution by the districts of Pasto, and the risk factors associated with the disease occurrence. A cross-sectional observational study was conducted in three-week-old guinea pigs (n = 270) from 71 farms distributed across 14 Pasto districts. Samples were taken for histopathological evaluation of the respiratory system to search for histopathological lesions compatible with pneumonia. The diagnosis of pneumonia was established in 73.7% of the study population. The districts of Socorro and Encano had a proportion of pneumonia greater than 79%. The farm size > 100 animals (OR 2.12; 95% CI 1.08–4.16), density of animals per cage, increases the odds of pneumonia. The biosecurity measures: facility washing (OR 0.18; 95% CI 0.06–0.52) and disinfection of farm facilities (OR 0.46; 95% CI 0.23–0.92) reduce the odds of pneumonia. The odds of pneumonia were lower (OR 0.04; 95% CI 0.05–0.43) in farms located at an altitude of 2200 to 2600 mts. Pneumonia constitutes an important pathology in the region of Pasto, Colombia. These findings highlight the need to conduct research to determine causality and preventive measures for the management of respiratory disease in the guinea pig.

Reduced milk yield remains a major constraint in grazing dairy systems under high tropical conditions, particularly when crossbreeding strategies are not adequately aligned with nutritional management. This study aimed to identify factors associated with reduced milk yield in non-supplemented KiwiCross crossbred grazing dairy cattle managed under high tropical conditions. Time-series analysis was used to characterize lactation curve patterns across genetic crossbreeding groups, a linear mixed model was fitted to evaluate the effects of genetic group, age, parity, and calving-related covariates on longitudinal milk yield, accounting for random effects associated with parity and temporal variability, and multivariable logistic regression models were used to assess the association between genetic composition and the probability of achieving an average milk yield greater than 10 L per cow per day. Time series analysis and mixed modeling consistently showed higher milk yields for Holstein cows and KiwiCross × Holstein F1 crossbreds, whereas F2 and F3 crossbreds exhibited significantly lower production. Logistic regression indicated that cows with 88% KiwiCross genetics had a markedly reduced odds of achieving average milk yields above 10 L after controlling for parity and calving season. Lactation curve analysis revealed the absence of a defined lactation peak and poor persistency during the first 100 days postpartum across all genetic groups, which could reflect low energy supplementation. Findings highlight the critical interaction between crossbreeding strategy and nutritional management in high tropical grazing dairy systems and provide practical insights to improve productivity in similar production environments.

Smallholder dairy systems in the high-altitude Amazonian tropics of Colombia are characterized by soil and forage conditions with mineral limitations, particularly for calcium (Ca) and phosphorus (P), and ionic antagonisms for potassium (K), magnesium (Mg), and Ca, which compromise mineral homeostasis in grazing cows and limit productivity and sustainability. Despite the importance of these interactions, the soil–plant–animal (SPA) relationship for minerals has not been systematically evaluated in smallholder high-altitude systems in the region. This study aimed to evaluate the soil-plant relationship for minerals and the soil-plant-animal relationship for Ca, P, and Mg in smallholder dairy herds of the indigenous communities located in the High-Putumayo region, Colombia. A cross-sectional study was conducted in 16 smallholder dairy farms (54 lactating cows). Soil samples were characterized for macro- and micronutrients; forage samples were analyzed for mineral composition; and serum Ca, P, and Mg were quantified. All mineral values were standardized to mmol·kg⁻¹ to allow integration across SPA. Principal component analysis (PCA) was used to assess mineral transfer dynamics between soil, forage, and cow serum. Soils across all orders (Andisol, Entisol, Histosol, Inceptisol) showed structural limitations for K and B and low bioavailable Ca and P. Forages exhibited consistently low Ca and P and excessive K and Mg, generating unfavorable Ca/P ratios and strong K–Mg–Ca antagonisms. Soil–plant correlations were weak and inconsistent for most minerals, except for Ca in Entisols. Serum results indicated normal Ca, elevated Mg, and borderline-low P concentrations in cows. SPA correlations revealed a significant positive continuum for Mg (soil–plant r = 0.52; plant–animal r = 0.56) and a significant negative relationship between soil P and serum P (r=–0.64), consistent with P fixation in volcanic soils. PCA suggests that mineral transfer efficiency was strongly dependent on soil order, with forage being the primary mineral source for cows. Mineral imbalances in these high-altitude systems are explained by poor forage mineral absorption and ionic antagonisms rather than absolute soil mineral concentrations. Nutritional mineral management requires a soil–plant–animal perspective, as soil mineral content alone does not reliably predict forage composition or animal mineral status.

Guinea pig ( Cavia porcellus ) production represents a key strategy for food security in rural households in the high-Andean region of southern Colombia. However, the sustainability of these production systems is limited by rising dependence on commercial feeds and the loss of traditional knowledge regarding local forage use. This study aimed to characterize the nutritional and ethnobotanical properties of unconventional forages used in guinea pig production systems in the high-Andean tropics. The methodological approach integrated participatory surveys, guided farm recognition, and collective knowledge dialogues to document plant use and management practices. Nutritional composition was assessed using near-infrared spectroscopy (NIRS), and compositional variables were analyzed through Principal Component Analysis and hierarchical clustering. A total of 24 forage species from different taxonomic families were identified. Species were grouped by their feeding role and associated with medicinal, human food, soil protection, ornamental, and repellent functions, highlighting their multifunctional value within smallholder systems. Nutritional analysis revealed substantial variability in protein content, structural fiber fractions, mineral composition, and digestibility indicators. Multivariate analysis identified four nutritional forage groups: Group 1 protein–mineral dense forages potentially relevant for growth and reproduction; Group 2 structurally fibrous forages associated with cecal fermentation processes; Group 3 high-moisture forages with intermediate nutritional contribution and complementary bulking function; and Group 4 intermediate-value basal forages. The integration of ethnobotanical knowledge with nutritional evaluation demonstrates that local forage biodiversity constitutes a strategic resource to diversify diets, improve feeding efficiency, reduce reliance on external inputs, and enhance the sustainability of guinea pig production systems in high-Andean tropics in Colombia.