Estrategia de cruzamientos para el mejoramiento de pollos Camperos. Un proyecto colaborativo INTA-universidad / Crossing strategy for breeding Campero chickens. An INTA-university collaborative project

RESUMEN El pollo campero es un ave destinado a sistemas productivos alternativos al industrial. Campero INTA es un cruzamiento simple entre poblaciones sintéticas generadas por INTA en Pergamino. Estas poblaciones se han mantenido cerradas y con bajo tamaño efectivo con el consiguiente efecto detrimental asociado a fenómenos de depresión endogámica. Con el objetivo de disponer de una población doble propósito con adecuados niveles productivos de carne y huevos y de rusticidad para ser utilizada en sistemas semi-intensivos que preservan el bienestar animal, se implementó un programa de relevamiento del recurso genético disponible y se diseñó un plan de cruzamientos dirigido a la producción de un híbrido terminal de tres vías. La secuencia incluyó la evaluación de cinco poblaciones sintéticas maternas (A, E, DE, ES y CE), la selección de dos de ellas (ES y A), su caracterización en cruzamientos simples recíprocos [(ESxA) y (AxES)], la elección de la alternativa (ESxA) como progenitor femenino y su cruzamiento por gallos de la estirpe paterna mejorada AH' para la obtención como producto final del pollo Campero Casilda. La evaluación de su patrón de crecimiento, conformación corporal, relación de conversión y caracteres productivos a la faena indican que tanto los machos como las hembras cumplen, como aves destinadas a la producción de carne, con las exigencias establecidas en el protocolo respectivo. La evaluación de los caracteres productivos a la madurez sexual, el patrón dinámico de aumento de peso del huevo y las curvas de postura califican a las hembras para su utilización como ponedoras.

ABSTRACT Campero chicken is a bird destined to production systems alternative to the industrial one. Campero INTA is a two-way cross between synthetic populations generated by INTA in Pergamino. These populations have remained closed and with a low effective size with the consequent detrimental effect associated with inbreeding depression. To have a dual-purpose population with adequate meat and egg production levels and rusticity to be used in semi-intensive systems that preserve animal welfare, a survey program of the available genetic resource was implemented and a crossbreeding plan to produce a terminal three-way hybrid was designed. The sequence included the evaluation of five maternal synthetic populations (A, E, DE, ES and CE), the selection of two of them (ES and A), their characterization in two-way reciprocal crosses [(ESxA) and (AxES)], the choice of the alternative (ESxA) as female parent and its crossing by roosters of the improved paternal line AH' to obtain the Campero Casilda chicken as the final product. The evaluation of their growth pattern, body conformation, conversion ratio and productive characters at slaughter indicate that both males and females satisfied the requirements as birds destined for meat production established in the respective protocol. The evaluation of productive characters at sexual maturity, dynamic pattern of egg weight gain and laying curves allowed to qualify the females as layers.

Variancia intrapoblacional para caracteres de la madurez sexual en gallinas del cruzamiento Campero Casilda

El análisis de componentes principales es una técnica estadística multivariada de síntesis de la información o reducción del número de variables, con la potencialidad de exponer relaciones entre caracteres no evidentes por sí mismas, contribuyendo así a una interpretación más eficiente de la información contenida en un conjunto de datos. Su aplicación a seis caracteres vinculados con la madurez sexual (edad y peso corporal a la puesta del primer huevo, peso del primero y de los 10 primeros huevos, número de días para poner los 10 primeros huevos y coeficiente de variación del peso de los mismos) posibilitó caracterizar la estructura de variabilidad intrapoblacional en gallinas del cruzamiento experimental de tres vías Campero Casilda. Las dos primeras componentes - PC1 y PC2- explicaron el 56% de la variancia fenotípica total. La consideración conjunta de ambas permitió identificar a un grupo de aves caracterizadas por iniciar su postura con mayor edad y mayor peso corporal, con un comienzo de la etapa productiva más regular, con huevos uniformes de mayor peso, una conjunción de caracteres deseable para el inicio del ciclo. La trascendencia de esta identificación radica en la utilidad reconocida del análisis de componentes principales como estrategia para generar índices biológicos de selección.

Principal components is a multivariate statistical technique of synthesis of information or reduction of the number of variables, with the potential to expose non-obvious relationships between characters, thus contributing to a more efficient interpretation of the information contained in a set of data. Its application to six traits associated to sexual maturity (age and body weight at first egg, weight of the first and the first ten eggs, number of days required to lay the first ten eggs and coefficient of variation of their weights) allowed to characterize the structure of intra-population variability in hens of the experimental three-way cross Campero Casilda. The first two components -PC1 and PC2- explained 56% of the total phenotypic variance. The joint consideration of both components allowed identifying a group of birds characterized for being older and heavier at sexual maturity, with a more regular onset of the productive phase, with uniform and heavier eggs, a conjunction of desirable characters for the beginning of the cycle. The importance of this identification lies in the recognized usefulness of principal components analysis as a strategy to generate biological selective indexes.

Endoscopia digestiva en una unidad de gastroenterología pediátrica. Evolución en los últimos 9 años / Nine years experience of digestive endoscopy in a pediatric gastroenterology unit

Introducción. El desarrollo de la endoscopia disgestiva pediátrica ha permitido progresar notablemente en el campo de la gastroenterología pediátrica. Hoy en día no es solo una técnica puramente diagnostica, sino también una técnica terapéutica de primer orden. Objetivos. Describir los resultados en endopia digestiva pediátrica en una serie extensa en los últimos 9 años. Material y métodos. Revisión retrospectiva de las endoscopias realizadas entre los años 2005 y 2013, ambos inclusive. Resultados. La frecuencia media annual de endoscopias en los últimos 9 años ha aumentado en un 25%. La primera indicación es la sospecha de enfermedad celíaca seguida del dolor abdominal. La sospecha de trastorno eosinofílico ha aumentado significativamente en los últimos años como indicación y como hallazgo en las endoscopias digestivas altas. En cuanto a las endoscopias digestivas bajas destaca el alto índice de resultados de normalidad, que han disminuido a lo largo del tiempo. Conclusión. La endoscopia digestiva infantil en manos de un endocopista experto es una técnica segura. En los útlimos años las variaciones en relación a número, indicaciones y resultados de dicha técnica está en consonancia con el mayor desarrollo de la subespecialidad y con el avance en el estudio de patologías emergentes (AU)

Introduction. Pediatric gastrointestinal endoscopy development has allowed amjor progress in the field of pediatric gastroenterology. Currently, it is not just a purely diagnostic technique but also a prime therapeutic technique. Aims. To describe an extensive serie on pediatric endoscopy in the las 9 years. Material and methods. Retrospective review of the endoscopies performed from January 2005 through 2013. Results. Mean annual frequency of endoscopies increased by 25%. Main indication was suspected celiac disease and was followed by abdominal pain. The suspicion of eosinophilic disorder has increased significantly in recent years as a indication and as a finding in upper endoscopies. Lower encoscopies were associated with a high rate of normal results altough with a declining incidence over time. Conclusion. Pediatric gastrointestinal endoscopy performed by experienced encoscopist a sage technique. Changes in frequency, indications and results were observed in digestive endoscopic procedures that are consistent with the further development of the subspecialty and with the progress in the study of emerging diseases (AU)

Land application of municipal landfill leachate: fate of ions and ammonia volatilization.

Landfill leachates are pollutants rich in ammoniacal N, Na, and K, but land application potentially offers an alternative for recycling these leachate nutrients. We applied landfill leachate corresponding to 0, 110, 220, 330, and 440 kg ha of total N, divided in three applications (July, August, and October 2008), onto the surface of an acidic (pH 5.5-6.0) clay (79% clay) Ultisol and monitored NH volatilization just after applications and microbiological (0-10 cm) and chemical attributes (0-60-cm soil depth) in August 2008, January 2009, and May 2009. Ammonium (up to 30 mg kg), NO (up to 160 mg kg), Na, K (up to 1.1 cmol kg each), and electrical conductivity (up to 1 dS m) increased transiently in soil following applications. Despite >90% of the total leachate N being ammoniacal, NO predominated in the first soil sampling, 14 d after the second application, suggesting fast nitrification, but it decreased in the soil profile thereafter. From 5 to 25% of the total applied N volatilized as NH, with maximum losses within the first 3 d. Applications inhibited (50%) the relative nitrification rate and increased (50%) hot-water-soluble carbohydrates in the soil at the highest rate. No effects were observed on soil microbial biomass C (114-205 mg kg) and activity (5-8 mg CO-C kg d) or on corn grain yields (6349-7233 kg ha). Controlled land application seems to be a viable alternative for landfill leachate management, but NO leaching, NH volatilization, and accumulation of salinizing ions must be monitored in the long term to prevent environmental degradation.

Iron metabolism in the pathogenesis of iron-induced kidney injury.

In the past 8 years, there has been renewed interest in the role of iron in both acute kidney injury (AKI) and chronic kidney disease (CKD). In patients with kidney diseases, renal tubules are exposed to a high concentration of iron owing to increased glomerular filtration of iron and iron-containing proteins, including haemoglobin, transferrin and neutrophil gelatinase-associated lipocalin (NGAL). Levels of intracellular catalytic iron may increase when glomerular and renal tubular cells are injured. Reducing the excessive luminal or intracellular levels of iron in the kidney could be a promising approach to treat AKI and CKD. Understanding the role of iron in kidney injury and as a therapeutic target requires insight into the mechanisms of iron metabolism in the kidney, the role of endogenous proteins involved in iron chelation and transport, including hepcidin, NGAL, the NGAL receptor and divalent metal transporter 1, and iron-induced toxic effects. This Review summarizes emerging knowledge, which suggests that complex mechanisms of iron metabolism exist in the kidney, modulated directly or indirectly by cellular iron content, inflammation, ischaemia and oxidative stress. The potential exists for prevention and treatment of iron-induced kidney injury by customized iron removal or relocation, aided by detailed insight into the underlying pathological mechanisms.

Ammonia volatilization in soil treated with tannery sludge.

The utilization of tannery sludge in agricultural areas can be an alternative for its disposal and recycling. Despite this procedure may cause the loss of nitrogen by ammonia volatilization, there is no information about this process in tropical soils. For two years a field experiment was carried out in Rolândia (Paraná State, Brazil), to evaluate the amount of NH(3) volatilization due to tannery sludge application on agricultural soil. The doses of total N applied varied from zero to 1200 kg ha(-1), maintained at the surface for 89 days, as usual in this region. The alkalinity of the tannery sludge used was equivalent to between 262 and 361 g CaCO(3) per kg. Michaelis-Menten equation was adequate to estimate NH(3)-N volatilization kinetics. The relation between total nitrogen applied as tannery sludge and the potentially volatilized NH(3)-N, calculated by the chemical-kinetics equation resulted in an average determination coefficient of 0.87 (P>0.01). In this period, the amount of volatilized NH(3) was more intense during the first 30 days; the time to reach half of the maximum NH(3) volatilization (K(m)) was 13 an 9 days for the first and second experiments, respectively. The total loss as ammonia in the whole period corresponded in average to 17.5% of the total N applied and to 35% of the NH(4)(+)-N present in the sludge. If tannery sludge is to be surface applied to supply N for crops, the amounts lost as NH(3) must be taken into consideration.

Evidence for cellular mediated immunity in an animal model of autoimmune pituitary disease.

The anterior pituitary gland can be involved in an inflammatory reaction mediated by lymphocytes that leads to various degrees of dysfunction. In seven rabbits immunized with homologous pituitary tissue in complete Freund's adjuvant, a focal lymphocytic infiltrate, and increased fibrosis was observed in five. These changes were patchy in distribution and limited to the anterior pituitary. No inflammation was observed in five control animals. When incubated with pituitary extract, partially purified lymphocytes from four of the five animals with altered pituitary histology demonstrated a significant (p less than 0.05) stimulation of 3H-thymidine incorporation. Measures of antipituitary antibodies using indirect immunofluorescence were negative in experimental as well as control animals. The present studies characterize the histologic changes and suggest that cellular immunity plays a role in the pathogenesis of experimentally induced autoimmune pituitary disease.