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Ítem Acceso Abierto Félix Guattari y el problema de la organización política: transversalidad, polivocidad y diagramatismo entre micropolítica y macropolítica(Cenaltes Ediciones, 2022) Ayala-Colqui, JesúsEl presente artículo elucida la posición de Félix Guattari sobre la organización política. Por este término entendemos la manera cómo, teórica y prácticamente, se construye y se desarrolla una militancia en lo real social, lo cual implica sostener una postura respecto al rol de los partidos, las instituciones y el Estado. A fin de precisar la especificidad del abordaje guattariano, desarrollado entre Psychanalyse et transversalité y Mille Plateaux, comparamos su planteamiento con los desarrollos tradicionales del anarquismo y el socialismo. Con ello se asegura una aprehensión de la posible singularidad de los conceptos guattarianos de transversalidad, polivocidad, diagramatismo, entre otros. Finalmente, se reflexiona sobre el lugar que ocupa la macropolítica en estos conceptos.Ítem Acceso Abierto La apuesta política de Silicon Valley: ¿tecnoliberalismo o ciber-liberalismo?(Universidad Santiago de Chile, 2022) Ayala-Colqui, JesúsEl presente texto tiene como objetivo analizar las implicancias políticas de la estrategia discursiva asociada a la imposición generalizada de las nuevas tecnologías (big data, algoritmos, inteligencia artificial, metaverso, bioingeniería, etc.) en la vida social. A partir del concepto de gubernamentalidad de Michel Foucault intentamos conceptualizar este fenómeno como una nueva táctica de gobierno que involucra discursos, relaciones de poder y producciones de subjetividad. En tal sentido, la hipótesis de nuestro texto es que los discursos asociados al auge e influencia de Silicon Valley, región del planeta que aglomera los principales centros empresariales de producción tecnológica avanzada, no se reduce al neoliberalismo, sino que avanza hacia una inédita forma de gobierno que denominamos “ciber-liberalismo”. Asimismo, dado que existe ya una literatura crítica sobre la apuesta política de Silicon Valley, nuestra propuesta discute con estos abordajes que emplean el término “tecnoliberalismo”.Ítem Solo Metadatos Surgical translocation and ultrasound bio-microscopy of the ovaries in rabbits(Elsevier, 2013) Cervantes, Miriam P.; Singh, Jaswant; Palomino Cano, Jesús Manuel, Adams, Gregg P.Experiments were designed to validate the use of ultrasound bio-microscopy (UBM) as a method for assessing ovarian structures in rabbits. In Experiment 1, female New Zealand White (NZW) rabbits (n = 4) were given an ovulation-inducing treatment and the ovaries were examined ex situ by UBM using a 25 MHz oscillating sector transducer before being processed for histology. Pairwise correlations revealed strong relationships between UBM and histology in the number (Mean ± SEM) of follicles ≥0.6 mm (17.3 ± 2.3 compared with19.0 ± 1.6, respectively; r = 0.96; P = 0.040), CL (8.5 ± 2.9 compared with 8.8 ± 3.0; r = 0.99; P = 0.003), the diameter of follicles (1.1 ± 0.05 compared with 1.1 ± 0.03 mm; r = 0.96; P = 0.035) and CL (2.1 ± 0.7 compared with 1.8 ± 0.6 mm, r = 0.99; P < 0.001). In Experiment 2, the ovaries of NZW rabbits (n = 12) were surgically translocated to a subcutaneous position in the flank region to permit serial examination of ovarian structures in vivo by UBM. Beginning 2 weeks after surgery, the ovaries were examined by UBM daily for at least 18 days, and again 2 months after surgery. Post-operative complications were minor, and both ovaries of each rabbit were identified consistently. The number and diameter of follicles ≥0.6 mm were readily visualized during each examination. Multiple corpora lutea were detected in two rabbits, and serial follicular and luteal dynamics in these two rabbits were used to document the consistency of UBM and the retention of ovarian function after surgery. It is concluded that UBM is a valid tool for instant assessment of rabbit ovarian structures (follicles, corpora lutea, and cumulus-oocyte complexes) ex situ, and for serial assessment in vivo using a transcutaneous approach. Surgical translocation had no apparent untoward effect on ovarian function.Ítem Solo Metadatos Foucault antes de Foucault: en torno a los manuscritos de los años cincuenta. Entrevista a Philippe Sabot por Jesús Ayala-Colqui(Cenaltes Ediciones, 2021) Sabot, Philippe; Ayala-Colqui, JesúsEl autor comparte la entrevista realizada a Philipe Sabot, docente en filosofía contemporánea y estudioso de las obras de Michael Foucault. La entre vista gira en torno a los manuscritos de Foucault de los años cincuenta.Ítem Solo Metadatos Launching of the Anaemia Research Peruvian Cohort (ARPEC): a multicentre birth cohort project to explore the iron adaptive homeostasis, infant growth and development in three Peruvian regions(British Medical Journal, 2021) Montag, Doreen; Delgado, Carlos A.; Quispe, Consuelo; Wareham, David; Gallo, Valentina; Sanchez-Choy, José; Sánchez, Victor; Anaya, Ruth; Flores, Elaine; Roca, Lorena; Mamani Urrutia, Víctor Alfonso; Rivera Medina, Juan; Velasquez, Pablo; Águila, Carlos del; Prendergast, Andrew; Palomino, JulioBackground: Preventing infantile anaemia and ensuring optimal growth and development during early childhood, particularly in resource-constrained settings, represent an ongoing public health challenge. Current responses are aligned to treatment-based solutions, instead of determining the roles of its inter-related causes. This project aims to assess and understand the complex interplay of eco-bio-social-political factors that determine infantile anaemia to inform policy, research design and prevention practices. Methods: This is a longitudinal birth cohort study including four components: (1) biological, will assess known blood markers of iron homeostasis and anaemia and stool microbiota to identify and genetically analyse the participants’ flora; (2) ecological, will assess and map pollutants in air, water and soil and evaluate features of nutrition and perceived food security; (3) social, which will use different qualitative research methodologies to explore key stakeholders and informants’ perceptions related to nutritional, environmental and anaemia topics, participant observations and a participatory approach and (4) a political analysis, to identify and assess the impact of policies, guidelines and programmes at all levels for infantile anaemia in the three regions. Finally, we will also explore the role of social determinants and demographic variables longitudinally for all study participants. This project aims to contribute to the evidence of the inter-related causal factors of infantile anaemia, addressing the complexity of influencing factors from diverse methodological angles. We will assess infantile anaemia in three regions of Peru, including newborns and their mothers as participants, from childbirth until their first year of age. Ethics and dissemination: Ethical approval was obtained from the Institutional Research Ethics Committee of the Instituto Nacional de Salud del Niño (Lima, Peru), CIEI-043-2019. An additional opinion has been granted by the Ethical Committee of Queen Mary University of London (London, UK). Dissemination across stakeholders is taking part as a continues part of the research process.Ítem Solo Metadatos Clima organizacional y satisfacción del usuario externo en los servicios de hospitalización del Instituto Nacional de Salud del Niño, 2017(Universidad Nacional Mayor de San Marcos, 2019) Fernández-Oliva, Danitza; Revilla-Velásquez, María; Kolevic-Roca, Lenka; Cabrejos-Castilla, Irma; Muchaypiña-Gallegos, Isabel; Sayas-Avilés, Iris; Chávez-Conde, Lizbeth; Mamani Urrutia, Víctor AlfonsoIntroducción: El clima organizacional dentro de las instituciones de salud y la satisfacción del paciente se utilizan para evaluar y mejorar la calidad de los servicios de salud. Objetivo: Determinar el clima organizacional y la satisfacción del usuario externo sobre la atención medica recibida en los servicios de hospitalización del Instituto Nacional Salud del Niño (INSN). Métodos: En el año 2017 se aplicó una encuesta para calificar el clima organizacional a los trabajadores de los servicios de hospitalización del Departamento de Medicina del INSN. La satisfacción del usuario externo se midió mediante la encuesta SERVQUAL aplicada a los usuarios externos. Resultados: La calificación del clima organizacional fue de 76,3%, considerada como mejorable; y la satisfacción global del usuario externo fue de 64,4%. El clima organizacional en las dimensiones de identidad, comunicación organizacional y estructura lograron el calificativo de saludable y la dimensión remuneración obtuvo el calificativo de no saludable. La dimensión mejor valorada por los usuarios externos fue: ¿durante su hospitalización recibió visita médica todos los días?; y la menos valorada: ¿los trámites para el alta fueron rápidos?. Conclusión: La calificación global del clima organizacional fue de 76,3% y la satisfacción global del usuario externo fue de 64,4% en el INSN.Ítem Solo Metadatos Usabilidad del proceso de atención de salud virtual en el período de cuarentena en los meses de mayo a julio 2020 por COVID-19 en el Instituto Nacional de Salud del Niño de Perú(Cuerpo Médico Hospital Nacional Almanzor Aguinaga Asenjo, 2022) Wilcamango-Ríos, Dreysi; Castillo-Narváez, Grethel; Mamani Urrutia, Víctor Alfonso; Inga-Berrospi, Fiorella; Revilla-Velásquez, María ElenaIntroducción: La pandemia COVID-19 ocasiono que se restrinja la atención por consultorio externo presencial en los establecimientos de salud, el gobierno establece acciones para continuar con la prestación de dichos servicios sanitarios. Objetivo del estudio: Describir la usabilidad de la atención de salud virtual en el período de cuarentena por la COVID-19 en el Instituto Nacional de Salud del Niño (INSN) de Perú. Material y métodos: Estudio transversal. Al INSN ingresaron 7697 pacientes para consulta externa virtual los meses de mayo a julio de 2020. El muestreo fue aleatorio simple y se tuvo una muestra de 374 participantes que cumplieron los criterios de selección. Se empleó el cuestionario de usabilidad de telesalud (TUQ). Se entrevistó telefónicamente a padres de pacientes que se atendieron por consulta virtual. Resultados: La edad promedio de los entrevistados fue de 36,2 años, mayoritariamente mujeres y de Lima. La edad promedio de los pacientes atendidos es 6,7 años, siendo mayormente varones (51,3%). El Smartphone fue el dispositivo más utilizado (97,6%); servicios de medicina los más consultados (84,4%), patologías más recurrentes las relacionadas al aparato respiratorio (10,4%). El 55,2% y 57,4% de los participantes está totalmente de acuerdo sobre la utilidad y facilidad de uso de la atención medica virtual respectivamente. Conclusiones: El uso de la telesalud en el INSN tuvo un impacto positivo, logró que los pacientes estén conectados con su médico a fin de continuar con sus tratamientos y brindar una óptima respuesta de atención medica en tiempo real.Ítem Solo Metadatos Niveles de hemoglobina de lactantes de 0 a 6 meses de edad hospitalizados en el Instituto Nacional de Salud del Niño, 2015(Universidad Nacional Mayor de San Marcos, 2019) Fernández-Oliva, Justa; Mamani Urrutia, Víctor AlfonsoIntroducción: En el Perú, contamos con pocos estudios relacionados con anemia que abarque el primer año de vida. Existen aspectos en la forma de establecer los diagnósticos, tratamientos e intervenciones a nivel poblacional, que requieren planteamientos y enfoques especializados que ayuden a mejorar este problema de salud pública. Objetivo: Determinar los niveles de hemoglobina de lactantes de 0 a 6 meses de edad hospitalizados en los servicios de medicina del Instituto Nacional de Salud del Niño en el año 2015. Métodos: Se revisaron 80 historias clínicas de pacientes hospitalizados. Se identificó a los lactantes cuya causa de hospitalización no estuviera relacionada a comorbilidades y que vivieran a nivel del mar. Resultados: El 55% de lactantes presentó anemia. El principal motivo de hospitalización fue bronquiolitis (36,3%) seguida de neumonía (20%). Conclusión: El 55% de lactantes de 0 a 6 meses hospitalizados presentaró anemia en nuestra investigación.Ítem Solo Metadatos Intención de recibir la vacuna contra la COVID-19 de los trabajadores de salud del Instituto Nacional de Salud del Niño antes del inicio de la vacunación en el Perú, enero-febrero 2021(Sociedad Peruana de Pediatría, 2021) Castillo Díaz, María Esther; Saravia Álvaro, Fridiz; Romero Ramos, César; Mamani Urrutia, Víctor AlfonsoIntroducción: Desde el inicio de la pandemia COVID-19 se han implementado una serie de medidas para controlar la diseminación de la misma en los países del mundo. Una de ellas y la más costoefectiva es la vacunación. Objetivo: Determinar la aceptabilidad de recibir la vacuna contra la COVID-19 de los trabajadores de salud antes del inicio de la vacunación en el Perú. Métodos: Se realizó un estudio transversal utilizando una encuesta anónima en línea. Se utilizó un muestreo por bola de nieve para captar al mayor número de trabajadores del Instituto Nacional de Salud del Niño-Breña en Lima - Perú. Después de procedimientos de control de calidad para excluir cuestionarios incompletos e inválidos, se analizaron 1004 encuestas completas. Se realizó un análisis descriptivo de las características de los trabajadores de salud y se utilizó regresión logística para modelar las asociaciones entre la disposición de vacunarse contra la COVID-19, las características de los participantes y variables estudiadas. Resultado: De los 1004 trabajadores de salud que completaron el estudio, 814 (81,1%) estaban dispuestos a recibir la vacuna contra la COVID-19. En la regresión logística múltiple, los que tuvieron mayor predisposición a vacunarse de manera significativa fueron médicos (OR=18,32; IC95%=8,07- 41,58), personal nombrado (OR=2,46; IC95%=1,16-5,21) y trabajadores diagnosticados con COVID-19 en los últimos 3 meses (OR=3,18; IC95%=1,11-9,06). Los 190 (18,9%) trabajadores que no tenían intención de vacunarse, manifestaron como principal factor influyente la preocupación sobre la seguridad (82,1%), seguido de la eficacia (12,6%) y la falta de información (12,1%). Conclusiones: Se determinó que la mayoría de trabajadores de salud del Instituto Nacional de Salud del Niño en Perú tiene la intención de recibir la vacuna Sinopharm contra la COVID-19 y que el principal motivo para no vacunarse fue la preocupación respecto a la seguridad de la vacuna.Ítem Solo Metadatos Ovarian synchronisation in wood bison (Bison bison athabascae) during the anovulatory season(Commonwealth Scientific and Industrial Research Organisation, 2013) Palomino Cano, Jesús Manuel; McCorkell, Robert B.; Woodbury, Murray R.; Adams, Gregg P.Two experiments were performed in wood bison during the anovulatory season to establish an effective protocol for ovarian synchronisation. In an untreated control phase, bison cows (n = 19) were examined daily to establish the interval to new follicular wave emergence (4.9 ± 0.7 days) for the purposes of comparison with the experimental treatments. In Experiment 1, bison were treated by transvaginal ultrasound-guided follicular ablation (n = 9) or with 2 mg, i.m., 17β-oestradiol (n = 10). In Experiment 2, bison were treated by follicular ablation (n = 9) or with 2 mg, i.m., 17β-oestradiol +100 mg, i.m., progesterone (n = 10). In Experiment 1, the interval to new wave emergence for control, follicular ablation and 17β-oestradiol-treated groups was 4.9 ± 0.7, 1.1 ± 0.1 and 3.1 ± 0.4 days, respectively (P < 0.05). The degree of synchrony was 2.4 ± 0.4, 0.2 ± 0.1 and 0.8 ± 0.2 days, respectively (P < 0.05). In Experiment 2, the interval to new wave emergence for control, follicular ablation and 17β-oestradiol + progesterone-treated groups was 4.9 ± 0.7, 1.2 ± 0.2 and 3.3 ± 0.3 days, respectively (P < 0.05), and the degree of synchrony was 2.4 ± 0.4, 0.2 ± 0.1, and 0.8 ± 0.2 days, respectively (P < 0.05). The degree of synchrony did not differ between ablation and hormone treatment groups in either experiment, but was greater in treatment groups than in the untreated control phase. Both follicular ablation and hormone treatment shortened and decreased the variability in the interval to follicular wave emergence in bison, but wave emergence occurred earlier after follicular ablation.Ítem Acceso Abierto Viropolitics and capitalistic governmentality: On the management of the early 21st century pandemic(Universidad Científica del Sur, 2020) Ayala-Colqui, JesúsThis text offers an analysis of the power apparatuses (dispositifs) employed in the management of the early 21st century Covid-19 pandemic. The paper is divided into two sections. The first part is oriented both towards a characterization of the mode of government that preceded the onset of the viral disease and towards an exposition of the power apparatuses it instrumentalized. This mode of government is referred to in the text as «capitalistic govermentality», a practice combining regimes of knowledge, economically encoded materialities, subjective formations and power apparatuses in order to maintain the valorization of private capital. The second part exposes the ways in which the apparatuses of capitalistic governmentality are modified and articulated in the context of the pandemic, through a phenomen given the provisional name of «viro-politics».Ítem Acceso Abierto Superstimulatory response and oocyte collection in North American bison during the non-breeding season(Elsevier, 2013) Palomino Cano, Jesús Manuel; McCorkell, Robert B.; Woodbury, Murray R.; Cervantes, Miriam P.; Adams, Gregg P.A 2 × 2 design was used to compare the ovarian response and oocyte collection characteristics in bison given a superstimulatory dose of eCG or FSH, with or without a follow-up dose of LH. Follicular wave emergence was synchronized by follicle ablation (Day −1) and bison were assigned randomly to two superstimulatory treatment groups (n = 10 per group): (i) a single intramuscular dose of 2500 IU of eCG given on Day 0, or (ii) two subcutaneous doses of 200 mg of FSH given on Days 0 and 2. On Day 4, 200 mg of LH was given intramuscularly in 5 bison in each superstimulatory treatment group. The study was done in two replicates (n = 20 per replicate) involving a crossover design so that each animal was given the opposite superstimulatory treatment (eCG or FSH) during successive replicates. Cumulus-oocyte complexes (COC) were collected by transvaginal ultrasound-guided follicle aspiration, and were classified according to morphologic attributes as compact, expanded, or denuded. Superstimulatory treatment with FSH (vs. eCG) resulted in the development of more follicles ≥5 mm (14.2 ± 1.41 vs. 8.2 ± 0.67; P < 0.05; mean ± SEM), and more follicles aspirated (12.4 ± 1.3 vs. 6.3 ± 0.6; P < 0.04). Follow-up treatment with LH (vs. no LH) resulted in a greater proportion of expanded COC (37% vs. 15%; P < 0.05), and a tendency for a higher COC collection rate (61% vs. 54%; P = 0.08). In summary, superstimulation with FSH (vs. eCG) resulted in twice as many follicles available for aspiration and nearly twice as many COC collected in bison during the anovulatory season, and follow-up treatment with LH increased the proportion of expanded COC collected.Ítem Acceso Abierto Prohibición de tenencia de mascotas en el reglamento interno de un edificio. Precisiones y sugerencias respecto al tema de los animales de compañía (mascotas) y perros guía(Gaceta Jurídica, 2019) Franciskovic Ingunza, Beatriz AngelicaLa autora aborda la STC Exp. N° 01413-2017-PA/TC, mediante la cual el Tribunal Constitucional se pronunció sobre la prohibición de tenencia de mascotas contenida en el reglamento interno de un edificio en el distrito de Magdalena del Mar. La autora sintetiza los puntos más trascendentes del fallo, así como reflexiona especialmente sobre la distinción entre animales domésticos y animales de compañía, y acerca de los animales como seres sintientes y el progresivo reconocimiento de su protección en legislaciones del Derecho comparado. Finalmente, enfatiza en las necesarias modificaciones del Código Civil para una mejor protección de los animales, así como destaca aspectos importantes de la ley que regula el uso de los perros guía por personas con discapacidad visual.Ítem Acceso Abierto Alpaca embryo transfer on a private Canadian farm(Canadian Veterinary Medical Association, 2018) Palomino Cano, Jesús Manuel; Jones, Lori; Vanhanen, Tom; Mastromonaco, Gabriela F.; Busato, Rachel; Adams, Gregg P.This study evaluated the feasibility of using an embryo transfer protocol in an alpaca farm in Canada. Alpaca donors and recipients were synchronized with 2 doses of gonadotrophin-releasing hormone (GnRH), 12 days apart. In donors (n = 5), superstimulation was induced with follicle stimulating hormone (FSH) given daily (40 mg) for 5 days beginning 2 days after the second GnRH treatment. Cloprostenol was given on the last day of FSH, the donors were bred 2 days later, embryos were collected 7 days after breeding. In recipients (n = 8), the second dose of GnRH was given the day before donor mating, and embryos were transferred on the day of donor collection. On average (± SEM), 5.2 ± 1.4 corpora lutea were detected and 2.5 ± 1.2 transferable embryos were collected in the donors. A mature corpus luteum was detected in 6/8 synchronized recipients and a single embryo was transferred to each. One recipient alpaca became pregnant and delivered a healthy baby 349 days after embryo transfer. This is the first report of successful embryo transfer in alpacas in Canada.Ítem Acceso Abierto Effects of follicular ablation and GnRH on synchronization of ovulation and conception rates in embryo recipient heifers(Elsevier, 2020) Palomino Cano, Jesús Manuel; Grand, Francois-Xavier; Vigneault, Christian; Blondin, Patrick; Sirard, Marc-AndréTwo experiments were performed to determine effects of follicular ablation (FA) and GnRH treatment on conception rate and synchronization in timing of ovulation among Holstein heifers. In Experiment 1, heifers were randomly allocated to four groups: Control (n = 84): prostaglandin F2α (PGF) IM on Day 0; FA-5/GnRH (n = 43): FA 5 days before PGF and GnRH on Day 2; FA-4/GnRH (n = 48):FA 4 days before PGF and GnRH on Day 2; andFA-3/GnRH (n = 21): FA 3 days before PGF and GnRH on Day 2. Ultrasonography was performed to determine follicular size, ovulation occurrence, and size of CL. In Experiment 2, heifers were assigned to three groups: Control (n = 264), FA-5/GnRH, and FA-4/GnRH. Pregnancy diagnosis was performed at Days 30 and 60. In Experiment 1, size of largest follicle at time of PGF was less variable (P ≤ 0.05) in all FA groups compared to the Control group. With the FA-5/GnRH and FA-4/GnRH treatments, there were greater (P ≤ 0.05) proportions of timing of ovulation synchronization (86 % and 85 %, respectively) compared to the Control (61 %) and FA-3/GnRH (62 %) groups. In Experiment 2, conception rates did not differ among groups, however, there were more pregnancies per cow when timing-of-ovulation treatments were imposed. In conclusion, follicular ablation combined with GnRH treatment resulted in an increased proportion of heifers having synchronized ovulation and, therefore, number of recipient heifers available for embryo transfer. Additionally, there was no effect on conception rate when there was greater synchronization in timing of ovulation among heifers.Ítem Acceso Abierto Effect of season and superstimulatory treatment on in vivo and in vitro embryo production in wood bison (Bison bison athabascae)(Wiley, 2019) Palomino Cano, Jesús Manuel; Mastromonaco, Gabriela F.; Cervantes, Miriam P.; Mapletoft, Reuben J.Two experiments were done using a two-by-two design to determine the effects of season and superstimulatory protocol on embryo production in wood bison. In Experiment 1 (in vivo-derived embryos), ovarian superstimulation was induced in female bison during the ovulatory and anovulatory seasons with either two or three doses of FSH given every-other-day (FSH × 2 vs. FSH × 3, respectively). Bison were given hCG to induce ovulation, inseminated 12 and 24 hr after hCG, and embryos were collected 8 days after hCG (n = 10 bison/group). In Experiment 2 (in vitro embryo production), ovarian superstimulation was induced in female bison during the ovulatory and anovulatory seasons with two doses of FSH, and in vivo maturation of the cumulus–oocyte complexes (COC) was induced with hCG at either 48 or 72 hr after the last dose of FSH. COC were collected 34 hr after hCG, and expanded COC were used for in vitro fertilization and culture. In Experiment 1, the number of follicles ≥9 mm, the proportion of follicles that ovulated, the number of CL, and the total number of ova/embryos collected did not differ between seasons or treatment groups, but the number of transferable embryos was greater (p < .05) in the ovulatory season. In Experiment 2, no differences were detected between seasons or treatment groups for any end point. The number of transferable embryos produced per bison was greatest (p < .05) using in vitro fertilization and was unaffected by season (1.5 ± 0.2 and 1.1 ± 0.3 during anovulatory and ovulatory seasons, respectively), in contrast to in vivo embryo production which was affected by season (0.1 ± 0.01 and 0.7 ± 0.2 during anovulatory and ovulatory seasons, respectively). Results demonstrate that transferable embryos can be produced throughout the year in wood bison by both in vivo and in vitro techniques, but the efficiency of embryo production of in vivo-derived embryos is significantly lower during the anovulatory season.Ítem Acceso Abierto Ovarian superstimulation and oocyte collection in wood bison (Bison bison athabascae) during the ovulatory season(Elsevier, 2014) Palomino Cano, Jesús Manuel; McCorkell, Robert B.; Woodbury, Murray R.; Cervantes, Miriam P.; Adams, Gregg P.The objective of the study was to establish an effective ovarian superstimulatory protocol and subsequently obtain oocytes from bison by transvaginal ultrasound-guided follicular aspiration. Two experiments involving 22 wood bison were done during the breeding season (September to December). In experiment 1, the bison were given a luteolytic dose of prostaglandin (Day 0) and underwent follicular ablation (Day 8) to induce ovarian synchrony. Synchronized bison were then assigned randomly to two groups (n = 11 per group) and given either 200 mg FSH diluted in saline sc, or 200 mg FSH diluted in a proprietary slow-release formulation (SRF) im on Days 9 and 11. Prostaglandin was given to both groups on Day 11 followed by 25 mg LH on Day 13. Oocytes were collected by transvaginal ultrasound-guided aspiration of follicles ≥5 mm on Day 14. In experiment 2, bison were synchronized as in experiment 1 and assigned randomly to one of two groups (n = 11 per group) and given either a single dose of 2500 IU eCG im on Day 9, or 200 mg FSH sc on Days 9 and 11. Prostaglandin was given to both groups on Day 11, and LH (25 mg) was given on Day 13. Oocyte collection was done as described in experiment 1. Cumulus-oocyte-complexes (COC) were classified according to morphologic characteristics. In experiment 1, more follicles ≥5 mm were detected on Day 14 in bison treated with FSH versus eCG (12.2 ± 1.73 vs. 5.8 ± 0.52; P < 0.05), and more COC were collected from FSH-treated animals (7.2 ± 1.41 vs. 3.4 ± 0.62; P < 0.05). In experiment 2, the FSH-saline and FSH-SRF groups had a similar number (mean value ± standard error of the mean) of follicles ≥5 mm on Day 14 (12.4 ± 1.49 vs. 13.8 ± 1.24, respectively) and a similar number of COC were collected (6.5 ± 1.13 vs. 6.3 ± 0.96, respectively). The proportion of COC collected per follicle aspirated and the percentage of compact, expanded, and denuded oocytes did not differ between groups in either experiment 1 or 2. In summary, a two-dose regimen of FSH diluted in saline and given sc or in a SRF and given im induced a similar ovarian response in wood bison, whereas a single dose of eCG resulted in a significantly lower ovarian response. Overall, COC were collected from 55% of follicles after transvaginal, ultrasound-guided needle aspiration in wood bison.Ítem Acceso Abierto Effects of eCG and progesterone on superovulation and embryo production in wood bison (Bison bison athabascae)(Elsevier, 2017) Palomino Cano, Jesús Manuel; Cervantes, Miriam P.; Woodbury, Murray R.; Mapletoft, Reuben J.; Adams, Gregg P.Experiments were done to determine if inclusion of eCG and progesterone in the superstimulation protocol will increase the ovarian response and embryo production in wood bison, and to provide preliminary information regarding the effect of season. In Experiment 1 (anovulatory season), bison (n = 26) were synchronized by follicular ablation (Day −1) and given FSH on Days 0 and 2, and assigned to 3 groups: Progesterone (Days 0–4), eCG (Day 3), or progesterone + eCG. On Day 5, bison were given hCG and inseminated 12 and 24 h later. Ova/embryos were collected 8 days after hCG. In Experiment 2 (ovulatory season), bison (n = 24) were synchronized and assigned randomly to two groups in which superstimulation was induced with FSH, either with or without eCG, as in Experiment 1. No differences among groups were found in ovarian response or embryo production in either experiment. The follicular count at wave emergence was positively correlated with the number of large follicles at the end of superstimulation in all groups. A significantly greater number of follicles present at wave emergence in the anovulatory vs. ovulatory season was associated with a greater number of CL at the time of embryo collection, but only half the number of freezable embryos. In conclusion, the number of transferable embryos collected (1–2/bison) was higher than in any previous report, but was not attributable to the inclusion of eCG or progesterone in the superovulatory protocol. The apparent effect of season on oocyte competence, and not superovulatory response, is worthy of further investigation.Ítem Acceso Abierto Inducing ovulation in wood bison (Bison bison athabascae) during the anovulatory season(Elsevier, 2015) Palomino Cano, Jesús Manuel; Cervantes, Miriam P.; Adams, Gregg P.As part of the development of a germplasm biobank to preserve the genetic diversity of threatened wood bison (Bison bison athabascae), a 2 × 2 factorial study was designed to determine the effects of ovulation induction agent and follicle maturity on the ovulatory response in wood bison during the anovulatory season. Bison (n = 32) were assigned randomly to four groups (n = 8/group) and treated with either pLH or hCG when a growing dominant follicle was either 8–9 mm or ≥10 mm. The ovaries were examined daily by ultrasonography to determine the timing of ovulation, and 7 days post-treatment to assess CL development. The proportion of bison that ovulated was greater in bison treated with hCG than pLH ([15/16] 94% vs. [8/16] 50%; P < 0.05), and when the dominant follicle was ≥10 mm vs. 8–9 mm at the time of treatment (88% vs. 56%; P < 0.05). The interval from treatment to ovulation was 37.0 ± 1.3 h and was not affected by induction agent or follicle size. However, synchrony of ovulation tended to be greater (P = 0.10) in the ≥10 mm group vs. the 8–9 mm group, and the ensuing corpus luteum was larger (15.3 ± 0.43 mm vs. 13.4 ± 0.36; P < 0.05). In conclusion, both ovulation inducing agent and follicle size influenced the ovulatory response in bison during the anovulatory season. Treatment with hCG was more effective than pLH for inducing ovulation in wood bison, and the effect was greater when treatment was given when the growing dominant follicle was ≥10 mm.Ítem Acceso Abierto Superovulation in wood bison (Bison bison athabascae) during the ovulatory and anovulatory seasons: effects of progesterone, treatment protocol and gonadotropin preparations for the induction of ovulation(Elsevier, 2016) Palomino Cano, Jesús Manuel; Cervantes, Miriam P.; McCorkell, Robert B.; Mapletoft, Reuben J.; Adams Gregg P.Experiments were done to determine the ovarian response and embryo production following superstimulation of wood bison. In Experiment 1 (Anovulatory season), the efficacy of pLH vs. hCG for inducing ovulation was compared in wood bison superstimulated with a single dose of pFSH in 0.5% hyaluronan and the effect of exogenous progesterone (PRID) on superovulatory response and embryo quality was examined. In Experiment 2 (Ovulatory season), the efficacy of pLH vs. hCG for the induction of ovulation was compared in wood bison superstimulated with pFSH in a single intramuscular dose vs. a two-dose regimen 48 h apart (split dose) in 0.5% hyaluronan. In Experiment 1, the number of CL was greater (P < 0.05) in bison treated with hCG than pLH (6.6 ± 1.8 vs. 2.8 ± 0.8) and in those that were not given PRID (6.0 ± 1.5 vs. 2.7 ± 1.0). There was no effect of progesterone treatment on embryo quality. In Experiment 2, the number of CL was greater (P < 0.05) in bison treated with hCG than with pLH (6.3 ± 0.8 vs. 3.8 ± 1.2) and in bison superstimulated with split dose vs. single dose of FSH (7.1 ± 0.9 vs. 3.0 ± 0.8). The number of ova/embryos and freezable embryos did not differ among groups in either experiment. In conclusion, hCG induced a greater ovulatory response than pLH in both seasons. Two doses of FSH induced the greatest superovulatory response during the ovulatory season. Exogenous progesterone did not improve embryo quality during the anovulatory season.
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