Producción de ensilados biológicos a partir de desechos de pescado, del ahumado de atún aleta amarilla (Thunnus albacares) y del fileteado de tilapia (Oreochromis sp) para alimentación de especies acuícolas

The purpose of this study was to produce silage and determine changes in the chemical and microbiological wastes smoked yellowfin tuna (Thunnus albacares) and tilapia filleting residue (Oreochromis sp), fermented with a commercial inoculum strain Lactobacillus casei Shirota. Procedures were used rustic and easy access to materials to be used as fish feed supplement. We determined the optimal ratio of molasses for fermentation, and proximate and microbiological account silage. The waste is mixed with sugar cane molasses as carbon source and commercial inoculums Lactobacillus casei strain Shirota. At the end of six days of fermentation both silages had acceptable physical and chemical characteristics. The proportions of molasses produced the highest acidification were 15 and 20% in both silage and found no significant differences (p < 0.05). Total coliforms, molds, yeasts and Salmonella sp were not present because they are inhibited by the ensiling process and that have characteristics suitable for use as a supplement in food for aquatic organisms.El propósito de este trabajo fue producir ensilados y determinar los cambios en la composición química y microbiológica de desechos del ahumado de atún aleta amarilla (Thunnus albacares) y del fileteado de tilapia (Oreochromis sp), fermentados con un inoculo comercial de Lactobacillus casei cepa Shirota. Se emplearon procedimientos rústicos y materiales de fácil acceso para utilizarse como suplemento en alimentos acuícolas. Se determinó el porcentaje de melaza óptima para la fermentación, la composición proximal y la cuenta microbiológica de los ensilados. Los desechos se mezclaron con melaza de caña de azúcar como fuente de carbono y el inoculo comercial de Lactobacillus casei cepa shirota. A los 6 días de fermentación ambos ensilados presentaron características físicas y químicas aceptables. Las proporciones de melaza que produjeron la acidificación mas alta fueron 15 y 20 % en ambos ensilados y no hubo diferencias significativas (p < 0.05). Los coliformes totales, mohos, levaduras y Salmonella sp no estuvieron presentes porque son inhibidos por el proceso de ensilaje y este tienen características adecuadas para su utilización como suplemento en alimentos para organismos acuáticos

Inclusión de compuestos antioxidantes naturales en dietas para peces para contrarrestar el estrés oxidativo

Oxidative stress is a type of damage caused by different kinds of pollutants such as xenobiotics, or by a deficiency in the body’s own antioxidant mechanisms. It occurs because of a disturbance in the balance between the formation of free radicals and cellular antioxidants, often resulting in cell damage and physiological disorders. Among the most common and studied impacts are: lipid oxidation, protein, and nucleic acid damage. As a strategy to offset or minimize such damage, including sources of natural antioxidants in food to fishes has been opted, which unlike synthetic ones, these do not have side effects on the body. Amid the most used compounds are α-tocopherol, ascorbic acid and phenolic compounds. Therefore, the results of research on the inclusion of these compounds in fish diets will be discussed in this paper.El estrés oxidativo es un daño causado por diversas clases de contaminantes como los xenobióticos, o por una deficiencia en los mecanismos antioxidantes del propio organismo. Se produce cuando se rompe el equilibrio entre la formación de radicales libres y los antioxidantes celulares, llegando a producir daño celular y trastornos fisiológicos. Dentro de los daños más comunes y estudiado se encuentran la oxidación de lípidos y proteínas, así como el daño en ácidos nucleicos. Como una estrategia para contrarrestar o minimizar estos daños se ha optado por incluir fuentes de antioxidantes naturales en los alimentos para peces, que a diferencia de los sintéticos no tienen efectos secundarios en el organismo. Dentro de los más utilizados se encuentran el α-tocoferol, el ácido ascórbico y los compuestos fenólicos. De acuerdo a lo anterior, en el presente trabajo se discutirán los resultados de investigaciones sobre la inclusión de estos compuestos en dietas para peces

A systematic review of store audit methods for assessing tobacco marketing and products at the point of sale

OBJECTIVE: Over four-fifths of reported expenditures for marketing tobacco products occur at the retail point of sale (POS). To date, no systematic review has synthesized the methods used for surveillance of POS marketing. This review sought to describe the audit objectives, methods, and measures used to study retail tobacco environments. METHODS: We systematically searched 11 academic databases for papers indexed on or before March 14, 2012, identifying 2,906 papers. Two coders independently reviewed each abstract or fulltext to identify papers with the following criteria: (1) data collectors visited and assessed (2) retail environments using (3) a data collection instrument for (4) tobacco products or marketing. We excluded papers where limited measures of products and/or marketing were incidental. Two abstractors independently coded included papers for research aims, locale, methods, measures used, and measurement properties. We calculated descriptive statistics regarding the use of 4 P’s of marketing (product, price, placement, promotion) and for measures of study design, sampling strategy, and sample size. RESULTS: We identified 88 store audit studies. Most studies focus on enumerating the number of signs or other promotions. Several strengths, particularly in sampling, are noted, but substantial improvements are indicated in the reporting of reliability, validity, and audit procedures. CONCLUSIONS: Audits of POS tobacco marketing have made important contributions to understanding industry behaviour, the uses of marketing, and resulting health behaviours. Increased emphasis on standardization and the use of theory are needed in the field. We propose key components of audit methodology that should be routinely reported