Ram semen deterioration by short-term exposure to high altitude is prevented by improvement of antioxidant status.

Abstract Ovine reproduction efficiency in herds at high altitude (ha) is lower than that at low altitude (la). In ewes, ha effects are due to hypoxia and oxidative stress. Our aim was to establish the effect of antioxidant vitamin supplementation on semen traits and antioxidant status of rams exposed to short or long time ha. A total of 32 rams native to la (~500 m) were used, 16 were kept at la and the other 16 were brought to ha (~3600 m), where they were placed in the same flock as the ha native rams (n=16). Half of the animals in each group were supplemented daily with vitamins C 600 mg and E 450 IU per os, during the entire experimental period, starting the 4th day after animal's arrival at ha (day 0). At days 0, 30 and 60 of treatment, blood and semen samples were collected for evaluation of antioxidant status and semen standard characteristics. Data were compared within each experimental time by analysis of variance using a general linear model. Elevated concentrations of oxidative stress biomarkers were present in blood from animals maintained at ha. Ejaculates from ha exposed rams showed decreased sperm concentration, progressive motility and viability, in addition to decreased antioxidant status in seminal fluid. A total of 30 days of oral supplementation with vitamins C and E prevented some ha negative effects on semen characteristics, mainly in recently ha exposed rams. It is concluded that exposure of rams to ha negatively affects semen quality, where oxidative stress plays a predominant role. These effects are mainly prevented by oral supplementation of vitamins C and E, which constitutes a simple and cheap alternative to improve semen quality of rams when they are moved to ha

In vitro fertilization and development of cumulus oocytes complexes collected by ultrasound-guided follicle aspiration in superstimulated llamas

The objective was to evaluate the developmental competence of cumulus-oocyte complexes (COC) collected by follicular aspiration in llamas treated with FSH or eCG. Llamas were assigned randomly to two groups (n = 16 per group) and treated, at the time of ovarian follicular wave emergence, with either: 1) 25 mg of FSH im, twice daily for 4 d; or 2) 1000 IU of eCG as a single i.m. dose. The start of gonadotropin treatment was considered Day 0. Both groups were given 5 mg of Armour Standard LH im on Day 6, and COC were collected by follicle aspiration on Day 7. Expanded COC collected from FSH- (n = 157) and eCG-treated llamas (n = 151) were fertilized in vitro using epididymal sperm, and presumptive zygotes were in vitro cultured in SOF medium for 8 d. The FSH and eCG treatment groups did not differ with respect to: the number of follicles 7 mm (16.0; 2.7 vs 14.0; 1.9, respectively; P = 0.5); the number of COC collected (11.5; 1.9 vs 9.7; 1.2; P = 0.4); the number of expanded COC (9.8; 1.4 vs 9.4; 1.2; P = 0.8); or the percentage of presumptive zygotes which developed into 2 to 8 cell stage embryos (65.3 vs 63.1), morulas (46.2 vs 42.5), or blastocysts (23.1 vs 20.5; P > 0.05). In conclusion, FSH and eCG treatments were equally effective for recovery of a high number of expanded COC which were used directly for in vitro fertilization. Furthermore, rate of embryo development was not significantly affected by the gonadotropin treatment used. © 2011 Elsevier Inc

Maternal Supplementation with Herbal Antioxidants during Pregnancy in Swine

The effects of a combined supplementation with herbal antioxidants during pregnancy on reproductive traits and piglet performance (number of live, dead, and mummified newborns and litter weight at birth and individual body weight at both birth and weaning) were assessed in a total of 1027 sows (504 treated and 523 control females) kept under commercial breeding conditions. The supplementation increased the number of live-born piglets (13.64 ± 0.11 vs. 12.96 ± 0.13 in the controls; p = 0.001) and the total litter weight, decreasing the incidence of low-weight piglets without affecting the number of stillbirths and mummified newborns. Such an effect was modulated by the number of parity and the supplementation, with supplementation increasing significantly the number of living newborns in the first, second, sixth, and seventh parities (0.87, 1.10, 1.49, and 2.51 additional piglets, respectively; p < 0.05). The evaluation of plasma vitamin concentration and biomarkers of oxidative stress (total antioxidant capacity, TAC, and malondialdehyde concentration, MDA) performed in a subset of farrowing sows and their lighter and heavier piglets showed that plasma levels of both vitamins were significantly higher in the piglets than in their mothers (p < 0.05 for vitamin C and p < 0.005 for vitamin E), with antioxidant supplementation increasing significantly such concentrations. Concomitantly, there were no differences in maternal TAC but significantly higher values in piglets from supplemented sows (p < 0.05). On the other hand, supplementation decreased plasma MDA levels both in the sows and their piglets (p < 0.05). Finally, the piglets from supplemented mothers showed a trend for a higher weaning weight (p = 0.066) and, specifically, piglets with birth weights above 1 kg showed a 7.4% higher weaning weight (p = 0.024). Hence, the results of the present study, with high robustness and translational value by offering data from more than 1000 pregnancies under standard breeding conditions, supports that maternal supplementation with herbal antioxidants during pregnancy significantly improves reproductive efficiency, litter traits, and piglet performance

Envejecimiento de la población

&bull;Actividades b&aacute;sicas de la vida diaria en personas mayores y factores asociados &bull;Asociaci&oacute;n entre depresi&oacute;n y posesi&oacute;n de mascotas en personas mayores &bull;Calidad de vida en adultos mayores de Santiago aplicando el instrumento WHOQOL-BREF &bull;Calidad de vida en usuarios con enfermedad de Parkinson, demencia y sus cuidadores, comuna de Vitacura &bull;Caracterizaci&oacute;n de egresos hospitalarios de adultos mayores en Puerto Natales (2007-2009) &bull;Comportamiento de las patolog&iacute;as incluidas como GES para el adulto mayor atendido en un Cesfam &bull;Contribuci&oacute;n de vitaminas y minerales a las ingestas recomendadas diarias en ancianos institucionalizados de Madrid &bull;Estado de salud oral del paciente inscrito en el Programa de Visita Domiciliaria &bull;Evaluaci&oacute;n del programa de discapacidad severa en Casablanca con la matriz de marco l&oacute;gico &bull;Factores asociados a satisfacci&oacute;n vital en una cohorte de adultos mayores de Santiago, Chile &bull;Pauta instrumental para la identificaci&oacute;n de riesgos para el adulto mayor autovalente, en su vivienda &bull;Perfil farmacol&oacute;gico del paciente geri&aacute;trico institucionalizado y posibles consecuencias en el deterioro cognitivo &bull;Programa de cuidados paliativos y alivio del dolor en Puerto Natales &bull;Rehabilitaci&oacute;n mandibular implantoprot&eacute;sica: efecto en calidad de vida relacionada con salud bucal en adultos mayores &bull;Salud bucodental en adultos mayores autovalentes de la Regi&oacute;n de Valpara&iacute;so &bull;Transici&oacute;n epidemiol&oacute;gica y el estudio de carga de enfermedad en Brasi

UNIVERSITY TEACHING-LEARNING PROCESS: REFLECTIONS THROUGHOUT THE AGENCY THEORY

En este trabajo se analizan algunas razones que pueden explicar el insuficiente nivel académico que se percibe en universidades de países en vías de desarrollo. El elemento de discusión es la relación profesor-alumno que es estudiada bajo el prisma de la teoría de agencia. Se concluye que en ausencia de eficientes mecanismos de control de la conducta tanto del profesor como del estudiante pueden proliferar vicios de responsabilidad que atentan contra la calidad del proceso de enseñanza-aprendizaje.This work analyses some reasons that might explain the insufficient academic level which is perceived in universities of developing countries. The discussion element is the teacher-student relationship which is studied under the perspective of the agency theory. It is concluded that in absence of efficient monitoring mechanisms of the teacher and student’s behavior might proliferate gaps of due diligence which attempts against the quality of the teaching-learning process

UNIVERSITY TEACHING-LEARNING PROCESS: REFLECTIONS THROUGHOUT THE AGENCY THEORY EL PROCESO DE ENSEÑANZA-APRENDIZAJE UNIVERSITARIO: REFLEXIONES A TRAVÉS DE LA TEORÍA DE AGENCIA

<p style="margin-bottom: 0cm;" lang="en-US" align="JUSTIFY"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;">This work analyses some reasons that might explain the insufficient academic level which is perceived in universities of developing countries. The discussion element is the teacher-student relationship which is studied under the perspective of the agency theory. It is concluded that in absence of efficient monitoring mechanisms of the teacher and student’s behavior might proliferate gaps of due diligence which attempts against the quality of the teaching-learning process.</span></span></p><br><p style="margin-bottom: 0cm;" align="JUSTIFY"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;">En este trabajo se analizan algunas razones que pueden explicar el insuficiente nivel académico que se percibe en universidades de países en vías de desarrollo. El elemento de discusión es la relación profesor-alumno que es estudiada bajo el prisma de la teoría de agencia. Se concluye que en ausencia de eficientes mecanismos de control de la conducta tanto del profesor como del estudiante pueden proliferar vicios de responsabilidad que atentan contra la calidad del proceso de enseñanza-aprendizaje.</span></span></p

Teoría de la educación : educación y cultura en la sociedad de la información

Resumen basado en el de la publicaciónSe analizan algunas razones que pueden explicar el insuficiente nivel académico que se percibe en universidades de países en vías de desarrollo. El elemento de discusión es la relación profesor-alumno que es estudiada bajo el prisma de la teoría de agencia. Se concluye que en ausencia de eficientes mecanismos de control de la conducta tanto del profesor como del estudiante pueden proliferar vicios de responsabilidad que atentan contra la calidad del proceso de enseñanza-aprendizaje.Castilla y LeónES