Rolando Barahona Rosales

Uso de la ultrasonografía en tiempo real para la estimación de la deposición de grasa y rendimientos de canales bovinas cebuinos provenientes de diferentes fincas de Colombia

El objetivo de este trabajo fue evaluar la estimacion del Ultrasonido en Tiempo Real (UTR) sobre la deposicion de grasa y medir las correlaciones del peso de las canales en frio y en caliente de novillos de diferentes condiciones de produccion en Colombia. Se realizaron mediciones por medio de ultrasonografia en tiempo real a 65 animales, a partir de los cuales se seleccionaron las imagenes obtenidas de 40 bovinos. Las tomas de imagenes por UTR fueron realizadas antes del beneficio de los animales en el frigorifico FRIGOCOLANTA, localizado en el municipio de Santa Rosa de Osos, Colombia. Mediante el uso de esta tecnica se determino el area del ojo del lomo (AOL) en el espacio intercostal entre las costillas 12 y 13 y la deposicion de grasa en el anca (P8), entre las tuberosidades coxales e isquiaticas. Estos datos fueron comparados con la informacion obtenida al sacrificio y desposte de los animales entre ellos peso vivo, rendimiento de la canal fria y caliente, el rendimiento de los 5 cortes minoristas de mayor importancia comercial de la cadena carnica Colombiana. De los resultados observados se pudo deducir que se encontro alta variabilidad de peso y AOL entre los animales estudiados, asociaciones positivas entre los pesos de la canal en frio y en caliente y una baja correlacion entre el AOL y la deposicion de grasa en el anca. Abstract The aim of the present study was to evaluate the value of the Real Time Ultrasonography (RTU) on the fat deposition and correlation between hot carcass and old carcass weight estimation and dressing percentage of steers under conditions of different production systems in Colombia. Measurements were made by ultrasound in real time to 65 animals, from which we selected 40 images obtained from cattle. Shots UTR imaging were performed before the interests of the animals in the refrigerator FRIGOCOLANTA, located in the municipality of Santa Rosa de Osos, Colombia. Using this technique we determined the Longissimus muscle area (AOL) in the intercostal space between the 12th and 13th ribs and the back fat thickness (P8) between the coxal and ischial tuberosities. These data were compared with information obtained by slaughtering of animals including live weight, carcass yield hot and cold, the performance of five retail cuts of major importance on the colombian commercial beef chain. From the obtained results it was deducted a high variability in weight and AOL among animals studied, positive associations between the carcass weights in cold and hot and a low correlation between AOL and deposition of fat in the rump.

Producción de dos cepas de Frankia sp. aisladas de Alnus acuminata H.B.K. por fermentación fed-batch

Nitrogen, one of the most important factors in the agricultural production systems, it is provides to the ground through chemical fertilization, natural phenomena and biological fixation by soil microorganisms as Frankia, a mechanism environmentally and economically viable. The use of Frankia as inoculant requires a thorough study related to the development and analysis of the behavior of the inocula in controlled conditions. Assessments were carried out focused on study and standardize the conditions that allow the development of a prototype of inoculant to base of Frankia strains Aan17, Aac49 and eca AacIII Chilean, prior to its production to large scale. It was determined the nutritional conditions that influence the growth and formation of specialized structures of Frankia in a fermentation fed-batch system on the scale of a liter. The dynamics of growth in the media evaluated showed highly significant differences (P< 0.001) observing the highest specific growth rate (0,025 h-1) and shorter doubling time (33.9 h) in the medium M1 root extract, yeast and glucose. With the average M3 root extract, yeast and molasses, it was noted the widest length of time of the exponential phase (64.86 h), the highest specific speed of substrate consumption (0,007 ) and the largest cellular performance based on the substrate (1.95 g/protein/substrate). It was evidenced that the nutritional components evaluated presented influence on the production of biomass (P<0.05 ), showing higher biomass production in regard to the reference medium Denzil Amina Purina (BAP) (P< 0.01 ).