Patricia Betancourth-Chaves

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.

Background and Aim: Milk contamination for human consumption is one of the biggest concerns worldwide. To prevent milk contamination, it is important to implement sustainable production practices that ensure animal health and guarantee veterinary drugs have been used properly. This study aimed to detect antibiotic residues and microbial contamination in commercially available pasteurized whole milk intended for human consumption. Materials and Methods: We conducted a cross-sectional study on all brands of pasteurized milk (n = 17) for human consumption in Medellin, Colombia, from February 30 to April 30, 2022. Six milk samples of each brand were collected every 15 days, resulting in 102 samples. IDEXX SNAPduo ST Plus test (IDEXX Laboratories Inc, Maine, USA) was used to detect cephalosporins residues to detect beta-lactam and tetracyclines. We detected mesophilic aerobic bacteria and coliforms using Chromocult Coliform Agar (Merck KGaA, Darmstadt, Germany) and Plate-Count Agar (Merck KGaA), respectively. Results: Beta-lactam residues were found in 24.4% of the brands. No tetracyclines or cephalosporins were detected. Mesophilic aerobic bacteria and coliform contamination were detected in 42.6% and 12.8% of the brands, respectively. No fecal coliform contamination was detected. Conclusion: This study demonstrated the presence of antibiotic residues and microbial contamination in commercially available pasteurized whole milk intended for human consumption in the study area, highlighting its potential public health implications. Keywords: biological contamination, cow milk, drug residues, food safety.

Introducción. La anisakiasis es una infección producida por parásitos de la familia Anisakidae, transmitida a los humanos por el consumo de pescado o mariscos crudos. En la actualidad, se considera una enfermedad emergente de interés en salud pública. Objetivo. Identificar la presencia de larvas de la familia Anisakidae en muestras de filetes de pescado crudo congelado destinados a consumo humano, en mercados de Medellín y su área metropolitana en Antioquia (Colombia). Materiales y métodos. Se realizó un estudio transversal, en el cual se buscó la presencia de larvas de la familia Anisakidae en filetes de pescado crudo congelado de tres mercados representativos de Medellín y su área metropolitana. Se analizaron 384 filetes listos para el consumo (197 sierras, 137 salmones, 37 atunes y 13 merluzas). Cada filete fue analizado mediante el método de prensado y luz ultravioleta. Los parásitos recolectados se identificaron a partir de claves taxonómicas para establecer el género, así como PCR convencional y posterior secuenciación Sanger, para determinar la especie. Resultados. Se encontraron 4 larvas en 4 de los 384 filetes (1,04 %) (IC95% 1,04 ± 1,01 %). Las larvas encontradas fueron identificadas como Anisakis pegreffi y el tipo de pescado en el cual se encontraron fue la sierra (Scomberomorus spp.). Conclusiones. De acuerdo con el estudio realizado, se evidencia la presencia de parásitos anisákidos en filetes de pescado crudo congelado en el área de influencia.