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Caracterización de perfiles serológicos de circovirus porcino tipo 2 de planteles de producción porcina intensiva en Chile
(Universidad de Chile, 2017)
PCVAD (del inglés, Porcine circovirus associated diseases). Entre estas, una de las más importantes en términos económicos y sanitarios para la industria porcina intensiva, es el PMWS (del inglés, Postweaning multisystemic wasting syndrome), que se...
Porcine circovirus type 2 (PCV-2) is a very small virus (17 nm of diameter), of icosahedral structure and simple circular DNA. PCV-2 is widely known to be the causative agent of several multifactorial diseases named PCVAD (Porcine circovirus asociated diseases). The most economic important disease caused by PCV-2 is the Postweaning multisystemic wasting syndrome (PMWS), which is characterized by progressive emaciation, growth retardation and wasting. PCV-2 infection is necessary but not sufficient to trigger the clinical presentation, there are other factors, individual and predial, that are involved in the development of the syndrome. Therefore, it is more common to find individuals infected with a subclinical presentation, immunocompromised and most susceptible to coinfections. In the present study, the serological profiles of 11 pig farms were characterized, whose geographic location is representative of production at the national level. A serological profile is a study carried out on groups of animals at different ages, to detect the presence of antibodies against PCV-2, and to determine patterns of infection. From each farm, sera was collected in 3-4 weeks; 10 weeks and 18-20 weeks old pigs, obtaining 16 samples per age. Each sample was evaluated by a comercial PCV-2 ELISA test for antibody detection. Additionally, antibody titres at 3 weeks were transformed to IPMA equivalent values (inmunoperoxidase monolayer assay), in order to evidence possible maternal interference with vaccination. Also, information about farms characteristics and management such as; PRRS status, vaccination, type of production system and size, were collected. All variables were statistically analyzed in order to establish if there were significant differences between the farms when considering these factors. The results show a characteristic behavior of the serological profiles, with a high antibody titre in 3 weeks old pigs, which decrease drastically over time, suggesting an efficient transfer of maternal immunity, but the effectiveness of the vaccination to generate antibodies is questioned. In addition, there is a high presence of the phenomenon of interference of maternal immunity with vaccination. Finally, the results of the statistical analysis show that all the analyzed factors generate significant differences between the serological profiles of the farms. The study allows us to conclude robustly that there is serological evidence of PCV-2 in all farms analyzed and that there are statistically significant differences between them when considering certain property factors, accepting the hypothesis of this study...
Porcine circovirus type 2 (PCV-2) is a very small virus (17 nm of diameter), of icosahedral structure and simple circular DNA. PCV-2 is widely known to be the causative agent of several multifactorial diseases named PCVAD (Porcine circovirus asociated diseases). The most economic important disease caused by PCV-2 is the Postweaning multisystemic wasting syndrome (PMWS), which is characterized by progressive emaciation, growth retardation and wasting. PCV-2 infection is necessary but not sufficient to trigger the clinical presentation, there are other factors, individual and predial, that are involved in the development of the syndrome. Therefore, it is more common to find individuals infected with a subclinical presentation, immunocompromised and most susceptible to coinfections. In the present study, the serological profiles of 11 pig farms were characterized, whose geographic location is representative of production at the national level. A serological profile is a study carried out on groups of animals at different ages, to detect the presence of antibodies against PCV-2, and to determine patterns of infection. From each farm, sera was collected in 3-4 weeks; 10 weeks and 18-20 weeks old pigs, obtaining 16 samples per age. Each sample was evaluated by a comercial PCV-2 ELISA test for antibody detection. Additionally, antibody titres at 3 weeks were transformed to IPMA equivalent values (inmunoperoxidase monolayer assay), in order to evidence possible maternal interference with vaccination. Also, information about farms characteristics and management such as; PRRS status, vaccination, type of production system and size, were collected. All variables were statistically analyzed in order to establish if there were significant differences between the farms when considering these factors. The results show a characteristic behavior of the serological profiles, with a high antibody titre in 3 weeks old pigs, which decrease drastically over time, suggesting an efficient transfer of maternal immunity, but the effectiveness of the vaccination to generate antibodies is questioned. In addition, there is a high presence of the phenomenon of interference of maternal immunity with vaccination. Finally, the results of the statistical analysis show that all the analyzed factors generate significant differences between the serological profiles of the farms. The study allows us to conclude robustly that there is serological evidence of PCV-2 in all farms analyzed and that there are statistically significant differences between them when considering certain property factors, accepting the hypothesis of this study...
Efectividad de los liceos públicos de excelencia en Chile
(Universidad de Chile, 2015-04)
Diseño de una estrategía de crecimiento para Compumat en la industria de software educativo
(Universidad de Chile, 2013)
Análisis regional de sitios abandonados con potencial presencia de contaminantes : Región del Libertador General Bernardo O'Higgins
(Universidad de Chile, 2013)
Este diagnóstico identificó y jerarquizó los Pasivos Ambientales abandonados de la Región del Libertador Bernardo O'Higgins, en relación al potencial riesgo de contaminación que estos producen en el medio ambiente y a la población expuesta. Este...
Plan de negocios para agencia de asesoría en migración laboral Chile - Canadá
(Universidad de Chile, 2016)
El presente proyecto, consiste en el desarrollo de un plan de negocios para una agencia de asesoría integral en el proceso de postulación de inmigración económica a Canadá. La agencia brindará el servicio a chilenos que, motivados por mejorar sus...
Evolución estructural y tectónica de la Isla Robinson Crusoe, Dorsal de Juan Fernández
(Universidad de Chile, 2016)
La geometría y evolución del volcanismo oceánico en ambiente intraplaca, parecen estar controlados primariamente por procesos magmáticos asociados a la fuente mantélica. Sin embargo, a menor escala, el ascenso magmático y la configuración de los...
Consenso sobre el manejo de eventos de aparente amenaza a la vida del lactante (ALTE): comisión de sueño, Sociedad Chilena de Neumología Pediátrica 2013
(Sociedad Chilena de Pediatría, 2014)
Un Evento de Aparente Aimenaza de la Vida o ALTE (del inglés: Apparent Life Threatening Event) corresponde a un episodio agudo que ante los ojos del observador pone en riesgo la vida de un lactante menor de 1 año. Debe presentar la combinación de 2...
Don Miguel Aylwin Gajardo. Un hombre con sentido de justicia
(Universidad de Chile, 2005)