Person: Lorenzo González, Pedro Luis
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First Name
Pedro Luis
Last Name
Lorenzo González
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Veterinaria
Department
Fisiología
Area
Fisiología
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
Item Follicular, Oocyte and Embryo Features Related to Metabolic Status in Primiparous Lactating does Fed with High-Fibre Rearing Diets(Reproduction in Domestic Animals, 2010) Arias Álvarez, María; García García, Rosa María; Rebollar, P.G.; Nicodemus, Nuria; Millán Pastor, María Pilar; Revuelta Rueda, Luis; Lorenzo González, Pedro LuisFertility of primiparous lactating does in the early postpartum (pp) period is very low mainly due to pronounced deficient energy intake, influencing oocyte and embryo developmental competence. The hypothesis used in this work was that high-lignin fibre diet supplied during the rearing period could increase feed intake and, consequently, improve the reproductive physiology and metabolic status of primiparous does in the early pp period. Diets with high-lignin [HL: 15.8% dry matter (DM)] or standard-lignin content (SL: 4.9% DM) were supplied until parturition time. No diet effects in serum oestradiol, progesterone concentrations and follicle categories were found in the histological study. Metaphase II rate of in vitro-matured oocytes was significantly higher in the SL vs the HL group (p < 0.001). Cytoplasmically degenerated oocytes (in terms of abnormal distribution of cortical granules) and follicular atresia rate were significantly lower in the SL group than in the HL group (p < 0.05 and p < 0.005 respectively). In addition, HL-fed does showed lower number of viable embryos and higher rate of retarded in vivo-recovered embryos compared with the SL group (p < 0.05). Neither in vitro embryo development of viable embryos nor conception rate was significantly different between groups. Feed intake increased during the first pregnancy in the HL group (p < 0.05), but not during early lactation. Serum protein, non-esterified fatty acid and leptin concentrations, as well as estimated body composition were similar in does fed with both diets. In conclusion, the enhancement of reproductive management by using highly lignified products in rearing diets does not seem to report physiological reproductive benefits affecting oocyte maturation rate and embryo viability in primiparous lactating does.Item Effect of leptin supplementation during in vitro oocyte maturation and embryo culture on bovine embryo development and gene expression patterns(Theriogenology, 2010) Arias Álvarez, María; Lorenzo González, Pedro Luis; Bermejo Álvarez, P.; Gutiérrez Adán, A.; Rizos, D.; Lonergan, P.Leptin is a metabolic hormone related to body condition and nutritional status that influences fertility in assisted reproductive technologies modulating oocyte and embryo quality. The aim of the present study was to establish the effect of various leptin concentrations (0, 10, 100 ng/mL) during in vitro oocyte maturation (IVM) and in vitro embryo culture (IVC) on bovine embryo development and quality in terms of gene expression. The relative mRNA abundance of the genes encoding solute carrier family 2 (facilitated glucose transporter) member 1 (SLC2A1), Bcl-2-associated X protein (BAX), placenta-specific 8 (PLAC8), aldo-keto reductase family 1 member B1 (AKR1B1) and leptin receptor (LEPR) were determined on Day 7 blastocysts by qRT-PCR. Cleavage rate (P 0.005) and blastocyst yield (P 0.05) was significantly lower when cumulus-oocyte complexes (COCs) were matured with 100 ng/mL leptin compared to 0 or 10 ng/mL leptin. No significant effect of different concentrations of leptin added during IVC on blastocyst yield was observed. The presence of 100 ng/mL leptin in both IVM and IVC further decreased cleavage rate (P 0.005) and blastocyst yield compared to the control group without leptin (P 0.05) and those supplemented with 10 ng/mL leptin or FCS (P 0.005). There was no evidence of any leptin-induced difference in the relative transcript abundance of SLC2A1, BAX and PLAC8 genes in Day 7 blastocysts. Expression of AKR1B1 was significantly lower in blastocysts from COCs matured with 100 ng/mL leptin compared to those matured with 0 or 10 ng/mL leptin (P 0.005). LEPR expression was up regulated when leptin concentration was increased from 0 ng/mL during IVM to 10 ng/mL during IVC, but it was down-regulated in the opposite situation (P 0.005). In conclusion, high leptin concentrations possibly related to obesity seem to be more detrimental rather than the absence of this hormone for preimplantation embryo survival; this effect is independent of LEPR gene expression and it does not influence expression of SLC2A1, BAX and PLAC8 genes in Day 7 blastocysts.Item Reproductive and Nutritional Management on Ovarian Response and Embryo Quality on Rabbit Does(Reproduction in Domestic Animals, 2014) Lorenzo González, Pedro Luis; García García, Rosa María; Arias Álvarez, María; García Rebollar, PilarRabbit does in modern rabbitries are under intensive reproductive rhythms. Females are high milk producers with high energetic expenses due to the extensive overlap between lactation and gestation. This situation leads to a negative energy balance with a mobilization of body fat especially in primiparous rabbit does. Poor body condition and poor health status severely affect the reproductive features (fertility rate and lifespan of the doe as well as ovarian physiology). This paper reviews some reproductive and nutritional approaches used in the last years to improve the reproductive performance of rabbit females, mainly focusing on the influence on ovarian response and embryo quality and with emphasis on epigenetic modifications in pre-implantation embryos and offspring consequences.Item Influence of hormonal and nonhormonal estrus synchronization methods on follicular and oocyte quality in primiparous lactating does at early postpartum period(Theriogenology, 2009) Arias Álvarez, María; García García, Rosa María; Torres Rovira, L.; González-Bulnes, Antonio; Rebollar, P.G.; Lorenzo González, Pedro Luis; Lorenzo González, Pedro LuisHigh-yield lactating does need effective estrus synchronization methods to improve their reproductive outcome by enhancing ovarian function. The aim of the current work was to analyze ovarian follicular and oocyte characteristics of hormonal and nonhormonal estrus synchronization regimes in primiparous lactating rabbit does (Oryctolagus cuniculus) in the early postpartum period (Day 11). Females were randomly treated with either (1) a hormonal standard treatment with 25 IU equine chorionic gonadotropin (eCG) 48 h before artificial insemination (eCG group) or (2) an alternative nonhormonal treatment consisting of doe-litter separation 24 h before artificial insemination (Bio group). No significant differences were found in serum estradiol and progesterone concentrations between experimental groups. During the histologic study, the Bio group presented a higher number of primordial (P < 0.05) and primary follicles (P = 0.07) compared with that of the eCG group, whereas secondary and antral follicular populations were similar. Rates of late atretic follicles assessed by the terminal deoxynucleotidyl transferase–mediated dUTP nick-end labeling technique were not different between treatments, but the eCG group showed a significantly higher number of mid-atretic follicles compared with that of the Bio group. Nuclear in vitro oocyte maturation (IVM), measured as metaphase II rate, and in vitro steroidogenic response of cumulus-oocyte complexes, measured by ELISA, did not show significant differences between treatments. However, confocal study showed that cytoplasmic maturation of oocytes, in terms of cortical granule migration rate, was significantly higher in the Bio group compared with that after the eCG treatment. In conclusion, transient doe-litter separation seems to improve ovarian response in terms of follicular health and oocyte competence compared with that after the eCG treatment. Therefore, a 24-h-long transient weaning could be an alternative nonhormonal method for synchronizing estrus in primiparous lactating rabbit does inseminated in the early postpartum period.Item Influence of metabolic status on oocyte quality and follicular characteristics at different postpartum periods in primiparous rabbit does(Theriogenology, 2009) Arias Álvarez, María; García García, Rosa María; Rebollar, P.G.; Revuelta Rueda, Luis; Millán Pastor, María Pilar; Lorenzo González, Pedro LuisLow reproductive performance of high-yield primiparous animals is closely associated with the metabolic stress caused by a simultaneous gestation and lactation. The aim of this work was (1) to analyze body composition and metabolic environment at three time points along lactation (at parturition time; in the lactation period [Day 11 postpartum]; and in the postweaning period [Day 32 postpartum]) of primiparous rabbit does (Oryctolagus cuniculus) and (2) to investigate the ovarian status at insemination time and the possible link with metabolic environment and with their reproductive performance. To this end, does were either submitted to a semi-intensive reproductive rhythm (Group S, inseminated on Day 11 postpartum) or an extensive rhythm (Group E, inseminated on Day 32 postpartum). Body energy (P < 0.05) and protein content (P < 0.001) as well as serum leptin (P < 0.05) and protein concentrations (P < 0.001) increased significantly along the postpartum period. At parturition, body lipid content was significantly lower and serum nonesterified fatty acids concentrations were significantly higher than that on Days 11 postpartum and 32 postpartum. Concerning ovarian status at insemination time, no significant differences were found in mean follicular stages, serum estradiol, progesterone, and prolactin (PRL) concentrations or in prolactin receptor (PRL-R) immunostaining. However, follicles in Group S showed a significantly higher apoptosis index than that of Group E (P < 0.001). The nuclear and cytoplasmic oocyte maturation rates of Group S were also significantly lower than that in Group E. In addition, conception rate and prolificacy were improved in Group E (P < 0.001 and P < 0.05, respectively). In conclusion, in the early postpartum period, metabolic status seems to impact negatively on ovarian follicle and oocyte quality leading to a poor reproductive outcome in primiparous rabbit does.Item Elaboración del contenido multimedia para el aprendizaje de reproducción de lagomorfos(2014) García García, Rosa María; García Rebollar, Pilar; Arias Álvarez, María; Revuelta Rueda, Luis; Lorenzo González, Pedro LuisSu objetivo es promover la difusión de la investigación básica y aplicada, como integración de las principales áreas de conocimiento adscritas en los diversos campos de las Ciencias Veterinarias y de los Alimentos. También aporta contenidos relativos a la Salud Pública, Seguridad Alimentaria y Medio Ambiente.Item Prácticas virtuales de fisiología(2021) Lorenzo González, Pedro Luis; García García, Rosa María; Arias Álvarez, María; Carrera Martínez, Daniel; Cuevas López, Jairo; Revuelta Rueda, LuisSe procedió a la grabación de los procedimientos experimentales de las asignaturas de Fisiología del Grado en Veterinaria y del Grado en CyTA y se han incluido en un formato presentación, en el que se exponen los conocimientos básicos de la práctica, los objetivos, el material y métodos, el procedimiento experimental en vídeo con explicaciones y finalmente la recogida de datos y la interpretación de los resultados. Así, se reduce el número de animales a utilizar en las prácticas porque no es necesario volver a hacer el procedimiento en el animal y el estudiante puede aprender a su ritmo y visualizar la presentación tantas veces como necesite para su aprendizaje, antes, durante y después de la práctica. Se ha contado con un amplio equipo en el que han participado PDI del departamento de Fisiología y de Producción Animal, PAS y estudiantes de grado y posgrado, de modo que la experiencia de todos ellos ha aportado un enfoque multidisciplinar, muy adecuado para la viabilidad del proyecto. El producto generado es un material duradero en el tiempo, que seguirá poniéndose a disposición de los estudiantes en cursos venideros.