Browsing by Author "Perea Ganchou, Fernando Pedro"

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Addition of clinoptilolite in the diet reduces uterine PMN leukocytes and open days in multiparous lactating dairy cows managed in a mountain tropical pasture‑based system
(2022) Garzón Prado, Juan Pablo; Quito Largo, Fernando Xavier; Calle Ortiz, Guido Rigoberto; Sinchi Merchán, Franklin Israel; Zuin Jarro, Jenny Fernanda; López Crespo, Gonzalo Estuardo; Galarza Lucero, Diego Andrés; Perea Ganchou, Fernando Pedro
This study aimed to assess the effect of adding clinoptilolite in the diet on uterine health and reproductive performance in multiparous lactating dairy cows managed in a tropical pasture -based system above 2500 m of altitude. Seventy-seven multiparous Holstein crossbred cows from two farms were allocated randomly into two groups: clinoptilolite supplemented cows (CLG, n = 42) and non-supplemented cows as control (CG, n = 35). Cows from CLG were supplemented with clinoptilolite from 30 days (50 g/cow/day) before to 60 days after calving (200 g/cow/day). In CLG cows, percentages of uterine PMN leukocytes (P < 0.0001) and proportion of subclinical endometritis (P = 0.0187) were lower than in CG. The interval calving to first corpus luteum was shorter (P = 0.0759) in CLG than CG, and calving to first service interval was similar between treatments. Cows from CLG became pregnant 35 days earlier than CG cows (P = 0.0224). On farm A, calving to conception interval was 18.1 days longer in CLG than in CG (P = 0.3750); in farm B, this interval was 86.2 days shorter in CLG than in CG (P = 0.0002). In conclusion, daily addition of clinoptilolite in the diet decreased the percentage of uterine PMN leukocytes, the proportion of cows with subclinical endometritis, and shortened the calving-conception interval in multiparous lactating dairy cows.
Adición de fluido folicular en la maduración de ovocitos de cerdas prepúberes
(Asociación Latinoamericana de Producción Animal, 2018) Argudo Garzon, Daniel Ernesto; Borja Tello, Diana Carolina; Wilches Correa, Veronica Elizabeth; Agurto Miranda, Valewska Andrea; Ayala Guanga, Luis Eduardo; Perea Ganchou, Fernando Pedro; Méndez Álvarez, María Silvana; Soria Parra, Manuel Elías; Argudo Garzon, Daniel Ernesto
La producción in vitro de embriones en los porcinos y otras especies de interés zootécnico es indispensable para el desarrollo productivo e investigativo. Diariamente se faenan cientos de cerdos en el camal municipal de Cuenca, Ecuador; donde sería posible rescatar material genético (complejos cúmulos ovocitos; Coc´s) valioso si se recuperan los ovarios de las cerdas; sin embargo, estos animales son beneficiados antes de la pubertad (<5 meses de edad) en cuyo caso la maduración de los Coc´s es deficiente. Se estableció como objetivo del estudio determinar el efecto del fluido folicular porcino (FFP) en maduración de Coc´s de cerdas prepúberes. Se obtuvieron ovarios (n=30) de cerdas faenadas en el camal municipal de Cuenca, los cuales fueron transportados al Laboratorio de Biotecnología de la Reproducción Animal de la Universidad de Cuenca, Ecuador. Inmediatamente se puncionaron los folículos antrales de 2-8mm con una aguja 18x1.5 pulgadas acoplada a una jeringa. El líquido folicular resultante fue filtrado para posteriormente realizar la búsqueda y recuperación de los Coc´s. Adicionalmente, se recuperó FFP, que fue centrifugado a 2000g x 20 minutos, esterilizado por doble filtración con filtros de jeringa estériles de 0.22µm y congelado hasta su uso. Para la maduración, los Coc´s de excelente y buena calidad (n=245) se dividieron aleatoriamente en tres grupos a los que se adicion diferentes porcentajes de FFP: 0% (n=79) ,10% (n=94) y 20%(n=72). Los Coc´s fueron incubados por 48hs en medio de maduración compuesto por TCM199, suero fetal bovino, FSH-p, HCG, piruvato de sodio, L-glutamina, gentamicina y FFP en una estufa con 5% de CO2, 38.5°C y 90%rh. Luego de madurados, los Coc´s fueron denudados por pipeteo en una solución dehialuronidasa 0.1% (p/v), inmediatamente teñidos conHoechst 33342 y observados en un microscopio de fluorescencia. Aquellos que presentaron la expulsión del corpúsculo polar fueron consideraron maduros y el resultado se expresó en porcentaje. Se aplicó un análisis de varianza (ANOVA) seguido de un test de Tukey. El grupo de Coc´s que no fue suplementado con FFP (0%) tuvo menor tasa de maduración (21,33+1,4 %) que los grupos suplementados con 10 (51,53+3,4%) y 20 % (52,93+5,7%) (P<0.05). Se concluye que, irrespectivamente del porcentaje adicionado el FFP fue necesario para mejorar la maduración de Coc´s de cerdas prepúberes
Administración de progesterona de acción prolongada después de la fertilización en ovinos superovulados y su relación con el tamaño de cuerpos lúteos y embriones
(2016) González Rosales, Mariana Gabriela; Quezada Moscoso, Sofía Margarita; Perea Ganchou, Fernando Pedro; Galarza Lucero, Diego Andrés
The effect of short- and long-acting progesterone (P4) in early ovine metaestrous upon the size and number of corpus luteum (CL), progesterone and cortisol concentration, and number of embryos recovery at days 7 and 13 post-artificial insemination (AI) were analyzed. The study was carried out in Irquis livestock farm owned by University of Cuenca with 21 Correidale ewes, which were submitted to estrous synchronization with P4 intravaginal devices and ovary stimulation with equine chorionic gonadotropin (Folligon ®) and follicle-stimulating hormone (Folltropin ®). After estrus, ewes were inseminated and randomized assigned to one of the following treatments: (T1; n=7) control; (T2; n=7) 6 mg of P4 (Progestar ®) on days 2, 3 y 4 post-IA, and (T3; n=7) 18 mg of long-acting P4 (Progesterone MAD-4 ®) on day 2 post-IA. Fecal P4 and cortisol were also assessed on days 2, 3, 4 and 5 post-AI. The size and number of the CL and embryos were performed by mid-ventral laparotomy on days 7 and 13; and also blood samples for P4 concentration determination were collected on day 13. A randomized block design was used to analysis of data. No statistics differences between treatments were found. Also, no embryos were recovered in any experimental group. In conclusion, the short- and long-acting P4 applied in early metaestrous did not affect the size and number of CL, serum P4 concentration, also, did not affect the concentration of P4 and cortisol in feces.
Análisis morfométrico y funcional de ovocitos bovinos obtenidos de ovarios de matadero y por aspiración folicular transvaginal en vacas criollas del altiplano ecuatoriano
(2020) Alvarado Ulloa, Jhonatan Marcelo; Perea Ganchou, Fernando Pedro; Soria Parra, Manuel Elías; Méndez Álvarez, María Silvana; Bueno Leon, Hernan Patricio; Iñiguez Gutierrez, Carlos Ulises; Argudo Garzón, Daniel; Galarza Lucero, Diego Andrés
This study assessed the morphometric and functional characteristics of oocytes from 10 native cows to the Ecuadorian Andes, collected by transvaginal follicular aspiration (OPU) and oocytes collected post mortem (PM) from abattoir ovaries. For this purpose, 1157 cumulus-oocyte complexes (CCOs) of the OPU group (n=271) and PM group (n=886) were recovered in 10 repetitions per group by follicular aspiration at 90 mm Hg pressure and classified as A, B or C, according to the characteristics of the cytoplasm and cumulus cells. The activity of the enzyme glucose 6 phosphate dehydrogenase (G6PD) and the integrity of the plasma membrane was determined by staining two groups of CCOs with cresyl brilliant blue (BCB +) and trypan blue, respectively. The size (diameter and volume) of the oocytes was evaluated using CaptaVisio® software v. 5.1. The data were analysed by logistic regression and by the SAS general linear model, and the means were compared by the least square method. The results showed that the oocytes of the PM group had a larger diameter (126.0 ± 0.48 vs. 122.7 ± 0.79 μm; p<0.01) and integrity of the plasma membrane (86.0 vs. 76.8%; p<0.05) than the OPU group. However, quality A and B oocytes did not show significant differences between groups with respect to plasma membrane integrity and BCB + values. The results suggest that, although the fact that the size and viability were more affected in the oocytes aspirated by OPU, those of quality A and B from both sources showed similar values regarding the integrity of the plasma membrane and metabolic condition to continue maturation.
Bovine corpus luteum affects embryo developmental competence and production
(CSIRO, 2019) Alvarado Ulloa, Jhonatan Marcelo; Tenemaza Cumbe, Milton Alejandro; Merchan Vargas, Shirley Lissette; Argudo Garzón, Daniel; Méndez Álvarez, María Silvana; Soria Parra, Manuel Elías; Galarza Alvarez, Luis Rodrigo; Ayala Guanga, Luis Eduardo; Hernandez Fonseca, Hugo Jose; Perea Ganchou, Fernando Pedro; Merchan Vargas, Shirley Lissette
This study was conducted with the aim to determine the effect of bovine corpus luteum on in vitro embryo production. Immature cumulus–oocyte complexes (COCs) were aspirated from abattoir ovaries from cows with (ipsilateral; CL+) and without (contralateral; CL-) corpus luteum (CL), and from cows without CL in any of the ovaries. The experiment was completed within 12 replicates (100 ovaries per group). COCs were cultured in maturation medium (TCM-199 supplemented with 10% fetal bovine serum, 100 µg/ml sodium pyruvate, 0.75 mg/ml L-glutamine, 4 µg/ml FSH-p, 2 µM cysteamine and 250 µg/ml gentamicin) followed by in vitro fertilization (hepes synthetic oviductal fluid medium supplemented with 10 µg/ml heparin) and in vitro culture (citrate synthetic oviductal fluid medium). On day 7 after in vitro fertilization the embryos were evaluated and classified into morulae (M), early blastocysts (EB), blastocysts (B), expanded blastocysts (ExB) and hatched blastocysts (HB), and the embryos with better quality were recorded. Data were analyzed by logistic regression and general linear model of the SAS, and means compared by least-squares means method. Results of cleavage, embryo rate at day 7, and rates of M + EB, B, ExB and HB are shown in Table 1. The number of embryos per ovary was greater (P < 0.01) in CL+ (1.16 ± 0.11) than in CL- (0.45 ± 0.15) and C (0.55 ± 0.15). Also, the number of embryos per cultured oocyte was significantly greater in CL + than in CL- and C (0.27 ± 0.02 vs 0.14 ± 0.03 and 0.15 ± 0.03 respectively, P < 0.01). The results of this study reveal that the presence of the corpus luteum in the ovary at the time of the oocytes recovery affects the developmental capacity of the bovine embryos, and such influence probably occur through intraovarian interactions.
BoviPure® density-gradient centrifugation procedure enhances the quality of fresh and cryopreserved dog epididymal spermatozoa
(2022) Perea Ganchou, Fernando Pedro; Muñoz León, Esteban Mauricio; Santiago Moreno, Julián; Galarza Lucero, Diego Andrés; Jara Jimbo, Diana Isabel; Paredes Quito, Efraín Bernardo; Samaniego Campoverde, Jorge Xavier; Méndez Álvarez, María Silvana; Soria Parra, Manuel Elías
BoviPure® is a salt solution containing colloidal silica particles coated with silane used to select sperm (e.g., ruminants) by density-gradient centrifugation (DGC). This research assessed the suitability of the BoviPure-DGC and swim-up methods for selecting dog epididymal sperm in fresh, chilled and frozen-thawed samples on post-treatment sperm quality. Sperm samples (n = 60 epididymides) were recovered by retrograde flushing from thirty orchiectomized adult dogs. Thereafter, 20 sperm pools, containing sperm aliquots of three randomly selected animals, were used for chilling (at 5 ºC for 24 h) and freezing (in liquid nitrogen vapors). Sperm selection by BoviPure-DCG and swim-up was performed in both individual and pooled samples, including non- selected samples as controls. Overall, after BoviPure-DGC selection a higher sperm retrieval rate was obtained than the swim-up selection in both individual (P < 0.05) and pooled (P < 0.01) samples. BoviPure-DGC improved (P < 0.05) the total (TM) and progressive (PSM) sperm mo- tilities, curvilinear (VCL) and straight-line (VSL) velocities, linearity (LIN), wobble (WOB), beat- cross frequency (BCF), and integrity of plasmatic (IPM) and acrosomal (IAM) membranes of in- dividual samples in comparison with non-selected samples. In pooled samples, however, the BoviPure-DGC improved (P < 0.05) the PSM, VCL, WOB, and IPM of chilled and frozen-thawed samples. The swim-up method improved (P < 0.05) only some kinematic variables of the indi- vidual (VCL, WOB and BCF) and cryopreserved pooled samples (VCL and ALH) in comparison with non-selected samples. In conclusion, BoviPure-DGC was more effective for recovering and selecting both fresh and cryopreserved dog epididymal sperm than the swim-up procedure improving the kinematic variables, and membranes intactness
Características morfológicas de huevos de gallina (Gallus gallus domesticus) para consumo en cuatro momentos del ciclo lunar
(Universidad de Cuenca, 2025-02-19) Sinchi Yumbla, Santiago Xavier; Sisalima Pachar, Fernando Javier; Perea Ganchou, Fernando Pedro
Scientific evidence has demonstrated an effect of the lunar cycle (LC) on productive and reproductive aspects in farm animals. However, there are no reports on the effect of the moon on hen egg morphology. This study evaluated the influence of four moments of the LC on external and internal morphometric characteristics of laying eggs. The lunar cycle was divided into new moon (NM), crescent quarter (CQ), full moon (FM) and waning quarter (WQ). Egg, yolk and albumen weight and dimensions, eggshell weight and thickness, and other variables derived from the above were recorded. Data were analyzed by analysis of variance using the general linear model, and means were compared with the least squares test. There was a statistical effect of LC on egg weight, length and width (P 0.0001), eggshell weight and thickness (P<0.001), and eggshell/egg ratio (P=0.0145), although egg shape did not vary between phases. Likewise, LC statistically influenced yolk weight, diameter and height (P<0.01), and albumen weight and diameter (P<0.01) but not albumen height (P=0.2998). In addition, yolk/egg (P=0.0520) and albumin/egg (P=0.0347) yolk/albumin (P=0.0463) ratios were also influenced by LC (P<0.05), but not yolk color (P=0.1118). In general, egg morphometric variables were higher in WQ and NM than in CQ and FM. In conclusion, an effect of the moon on the external and internal characteristics of laying eggs was observed. Both yolk, albumen, shell and whole egg were heavier in NM and WQ than in the other two LC phases.
Caracterización morfológica y funcional de ovocitos de cobaya en dos estadios del ciclo estral
(Universidad de Cuenca, 2023-07-03) Bravo Vega, Edisson Fernando; Castro Calle, Katherine Marisol; Perea Ganchou, Fernando Pedro
The morphological and functional characteristics of guinea pig oocytes were studied according to the type of COC and stage of the estrous cycle. Forty guinea pigs, synchronized with oral progesterone (Regumate®) for 15 days, were used. Ovaries were collected at periovulatory (day 2) and diestrous (day 9) post-synchronization stage, and 100% of COCs were categorized by morphology into A, B and C. Mitochondrial distribution (MD), nuclear status, oocyte diameter and zona pellucida (ZP) thickness were determined, and in 50% of these, Brilliant Cresyl Blue (BCB) staining was applied. A total of 1053 COCs were obtained (49.9% periovulatory and 50.1% diestrous). From these, 23% were A, 47.5% B and 29.5% C. It was determined that in the periovulatory stage there was a greater percentage of BCB+, while in the diestrous stage a greater percentage of BCB- was obtained. In both the periovulatory and diestrous stage, diffuse DM had a greater percentage with statistical significance. There was a greater proportion of immature oocytes followed by degenerate and the mature oocytes in both stages of the estrous cycle. Oocytes in diestrous were larger in diameter than oocytes in periovulatory (p=0.0126), while the zona pellucida was thicker in periovulatory than in diestrous (p<0.0001). In conclusion, the application of non-invasive methods in guinea pig oocytes to identify characteristics of quality, development, maturation and morphometry were effective.
Caracterización morfométrica de útero, ovarios y ovocitos de cobayas criollas (Cavia porcellus) de la sierra sur de Ecuador
(ALPA, 2018) Fernandez Jara, Adriana Estefania; Encalada Sinche, Tania Alexandra; Guaman Guallpa, Anabel Gabriela; Ayala Guanga, Luis Eduardo; Argudo Garzon, Daniel Ernesto; Rosales Jaramillo, Cornelio Alejandro; Perea Ganchou, Fernando Pedro; Fernandez Jara, Adriana Estefania
Los cuyes o cobayos son animales de gran interés productivo en la sierra ecuatoriana y en otros países andinos, debido a que constituyen una fuente alimenticia de alto valor nutritivo y de consumo tradicional; sin embargo, muchos aspectos morfológicos y fisiológicos de estos animales han sido poco estudiados. Se estableció como objetivo de este estudio caracterizar morfométricamente el útero, ovarios y ovocitos de cobayas (Cavia porcellus) nativas de la Sierra sur del Ecuador. Se utilizaron 18 cobayas primíparas de línea genética Azuay y Cañar, con un peso promedio 1002.7 ± 212.7 gramos, en buen estado de salud, que pertenecían a la Unidad de Producción de Cuyes de la Facultad de Ciencias Agropecuarias de la Universidad de Cuenca. Los animales fueron faenados siguiendo las normas de bioética y bienestar animal consideradas por la Organización Mundial para la Salud Animal. Luego de ser identificado y aislado el aparato reproductor de cada hembra, los ovarios fueron retirados y colocados en solución fisiológica a 37ºC, hasta ser pesados en una balanza analítica y medidos su largo y ancho con un calibrador metálico. Los úteros fueron removidos y separados del tejido circundante, e inmediatamente medidos los cuernos derecho e izquierdo, así como también el cuerpo y cuello uterino. Los ovocitos obtenidos (n=48) mediante la técnica de slicing (cortes múltiples sucesivos de la corteza ovárica) dentro de una placa de Petri con solución fisiológica, fueron identificados y lavados varias veces, y removidas las células de cumulo mediante pipeteo repetido en un medio con hialuronidasa al 0,1%. Luego fueron fotografiados y medidos con un software (AmScope V3.7) calibrado para realizar mediciones microscópicas. Los datos se analizaron con el programa estadístico SAS. El peso de los ovarios fue 77±27 miligramos (derecho 77,7; izquierdo 76,3), y su largo y ancho de 8,05±1,25 (derecho: 8,27; izquierdo: 7,83) y 5,27±1,14 mm (derecho: 5,38; izquierdo: 5,16) respectivamente. El cuerno derecho midió 7,97±1,74 cm y el izquierdo 7,85±1.75 cm; mientras que el cuerpo y el cuello uterino midieron 1,2±0,37 y 1,1±0,22 cm respectivamente. La zona pelucida de los ovocitos midió 12,1±2,5 mμ, mientras que su diámetro (sin zona pelucida) y volumen fueron de 75,6±8,2 μm y 234003,8±76547,1 μm3 respectivamente. Se concluye que el peso y las dimensiones de los ovarios derecho e izquierdo de cobayas nativas es similar. Asimismo, conocer las características morfológicas del aparato reproductivo de esta especie es de gran valor para comprender mejor los aspectos funcionales de la misma.
Competencia del ovocito bovino obtenido por ovum pick-up valorado mediante el azul brillante de cresilo
(2018) Ayala Guanga, Luis Eduardo; Samaniego Campoverde, Jorge Xavier; Nieto Escandón, Pedro Emilio; Rodas Carpio, Ermes Ramiro; Dután Sanango, Jorge Bolívar; Calle Ortiz, Guido Rigoberto; Murillo Apolo, Yury Agapito; Vázquez Mosquera, Juan Mesías; Argudo Garzón, Daniel Ernesto; Perea Ganchou, Fernando Pedro
The objective of the present study was to evaluate the bright blue cresyl (BCB) test as an indirect method to select competent oocytes for the in vitro production of embryos (IVP). The cumulus-oocyte complexes (COC) were obtained from two Creole heifers subjected to two treatments: T1 = COC recovered by OPU (ovum pick-up) previous stimulation with FSH-LH; T2 = COC recovered from non-stimulated animals (control).The two heifers were alternated in the two treatments and five repetitions were done. Recovered COCs were classified into types A, B, C and D. Then the BCB test was applied to each of the COC types to determine if they were BCB+ or BCB-. T1 allowed to recover 5.2 more COC than T2 (p<0.05). When applying the BCB test, it was determined that all type A oocytes of T1 and T2 were BCB+; that is, they finished their growth and were ready to start the process of in vitro maturation; however, about 50% of the type B, C and D COCs of T1 and T2 were BCB+. It is concluded that the selection of COC based on morphological characteristics is a reliable method only for type A and has a 50% error for COC type B, C and D and, therefore, the application of the BCB test allows to improve this selection non-invasively
Efecto de la presión de vacío sobre las características morfológicas de ovocitos bovinos obtenidos de ovarios de matadero
(Asociación Latinoamericana de Producción Animal, 2018) Argudo Garzon, Daniel Ernesto; Quezada Contreras, Adrian Ignacio; Mocha Zhispon, Armando Ramiro; Soria Parra, Manuel Elías; Méndez Álvarez, María Silvana; Ayala Guanga, Luis Eduardo; Galarza Alvarez, Luis Rodrigo; Perea Ganchou, Fernando Pedro; Perea Ganchou, Fernando Pedro
El efecto adverso de la presión de vacío sobre la competencia de los ovocitos recuperados mediante ovum pick up (OPU), y de los embriones obtenidos de estos, ha sido documentado previamente, pero poco se sabe sobre su efecto en las características morfológicas de los ovocitos. Se estableció como obejtivo del estudio evaluar el efecto de la presión de vacío sobre las características morfométricas de ovocitos bovinos recuperados de ovarios de matadero. El estudio se realizó en el Laboratorio de Biotecnología de la Reproducción Animal de la Universidad de Cuenca, Ecuador. Los ovarios recolectados (n=252) de un matadero local fueron divididos al azar de manera homogénea en tres grupos con diferente presión de aspiración folicular: 50, 65 y 80mmHg. Se aspiraron los folículos entre 2-8 mm de diámetro; para la punción se utilizó una aguja 18Gx1.5 pulgadas conectada a una bomba de vacío. Se recuperaron y seleccionaron los mejores COC´s (complejos cúmulos ovocito) de cada grupo: 50 (n=283), 65 (n=263) y 80 mmHg (n=226). Un 30% de cada grupo fueron colocados en un medio con hialuronidasa al 0,1% (p/v) y denudados por pipeteo sucesivo. Los ovocitos se fotografiaron con una cámara montada sobre un microscopio provisto con un software (AmScope V.3.7) calibrado para realizar mediciones microscópicas. El otro 70% de COC´s fueron incubados por 24hs en medio de maduración a base de TCM199, suero fetal bovino, FSH-p, estradiol, piruvato de sodio, L-glutamina y gentamicina en una estufa con 5% de CO2, 38.5°C y 90%rh. Luego de madurados, los COC´s fueron denudados y medidos como se indicó anteriormente. Los datos se analizaron con el programa estadístico SAS. Los ovocitos aspirados con 50mmHg antes de la maduración tuvieron un diámetro (sin zona pelúcida) y un volumen (125.8±0.5 µm y 1052327.9±11792.9 µm3) mayor que los obtenidos con 65 (123.3±0.5 µm y 990510.6±12603.9 µm3) o 80 mmHg (122.2±0.5 µm y 992296.4 ± 13652.9 µm3) (P<0,001). Luego de ser madurados, los ovocitos obtenidos con 50 mmHg tuvieron un diámetro y un volumen (121.9±0.6 µm y 954686.4±14072.2 µm3) mayor que los recuperados con 65 (120.1±0.6 µm y 913819.1±14879.8 µm3) (P<0,05), pero fueron similares a los obtenidos con 80 mmHg (121.4±0.7 µm y 945211.9±16359 µm3). Como conclusión, a mayor presión de vacío los ovocitos tendieron a ser más pequeños, es decir, tuvieron menor diametro y volumen. Asimismo, independientemente de la presión de aspiración, los ovocitos redujeron su diámetro y volumen como consecuancia de la maduración.
Efecto de dos protocolos de congelación de espermatozoides epididimarios de cobayo sobre las características espermáticas post-descongelación
(Universidad de Cuenca, 2023-09-27) Calderón Guamán, David Fernando; Pintado Sangurima, Sandro Rubén; Perea Ganchou, Fernando Pedro
The current study evaluated the effect of two freezing protocols in guinea pig epididymal spermatozoa on post-thaw sperm characteristics. For this purpose, from a total of twenty-two guinea pigs, forty-two testes were collected from a local slaughterhouse. Spermatozoa were recovered by retrograde flushing from the epididymal tail using 1 mL of TCG-YH medium (tris, citric acid, glucose 20% [v/v] egg yolk). Samples were refrigerated for 60 min at 5°C, loaded into 0.25 mL straws and frozen in TCG-YH and 5% glycerol using two freezing protocols: 1) Conventional protocol (CC) using double freezing ramps (24 and 10 cm above the liquid nitrogen level for 3 and 2 min respectively) in a polystyrene box, and 2) Protocol with programmed cooling rates (CP) using an automatic freezer. Data were analyzed by analysis of variance using the general linear model and means were compared with the least squares test. Kinetic parameters decreased drastically after freezing and thawing. Most kinetic parameters and the percentage of spermatozoa with intact plasma and acrosomal membrane were higher (P < 0,05) with the CC protocol than with the CP protocol. However, the percentage of post-thaw sperm DNA fragmentation did not vary between treatments (P > 0,05). In conclusion, freezing guinea pig epididymal sperm samples with the conventional procedure resulted in better sperm quality than that attained with programmed freezing.
Efecto de la adición de melatonina en el medio de maduración y/o vitrificación de ovocitos sobre la producción in vitro de embriones bovinos
(2020) Méndez Álvarez, María Silvana; Argudo Garzon, Daniel Ernesto; Soria Parra, Manuel Elías; Galarza Alvarez, Luis Rodrigo; Perea Ganchou, Fernando Pedro
The effect of the addition of melatonin (Mt) on the maturation and / or vitrification of bovine oocytes on cleavage and subsequent embryonic development was evaluated.Oocyte-cumulus cell complexes (COCs) were obtained from creole cows by ovum pick up (OPU) and by follicular aspiration from abattoir ovaries (AO). From the pool of oocytes obtained from both sources, those with homogenous cytoplasm and three or more compact layers of cluster cells were selected. The selected COCs were randomly assigned to five treatments: T1, matured with Mt and vitrified without Mt; T2, matured and vitrified with Mt; T3, matured without Mt and vitrified with Mt; T4 (control) matured and vitrified without Mt; T5, matured without Mt and not vitrified. The concentration of Mt in the maturation and vitrification media was 0.01 µM (10-9 M). The oocytes were matured, vitrified, fertilized and the presumed zygotes cultured until day 7 post-fertilization in vitro. The data were analysed by logistic regression. Regardless of the origin of the oocytes, cleavage rate (C) and embryo production (EP) was similar between treatments. The C in the OPU oocytes was greater in T4, and the EP was similar between treatments. In AO, the results did not vary between treatment in C and EP. In conclusion, Mt reduced the C in oocytes collected by OPU, while it did not affect EP. In the AO oocyte source, the addition of Mt did not affect the C nor the EP.
Efecto de la adición de tres factores de crecimiento (EGF, LIF, ITS) y su combinación sobre la maduración in vitro de ovocitos de cobaya
(Universidad de Cuenca, 2025-04-16) Bosmediano Begay, Evelyn Melissa; Victoria Grefa, Erick Jossue; Perea Ganchou, Fernando Pedro
This study evaluated the effect of adding epidermal growth factor (EGF), leukemia inhibitory factor (FIL), insulin-transferrin-selenium (ITS), and their combination on the in vitro maturation (IVM) of guinea pig oocytes. Ovaries were collected from a local slaughterhouse and transported to the laboratory at 34–37 °C. Cumulus-oocyte complexes (COCs) were recovered by slicing and selected based on morphological quality; only suitable COCs were used for IVM. Selected COCs were randomly assigned to five treatments: T0 (control): base medium (BM) composed of TCM-199 supplemented with sodium pyruvate, glutamine, gentamicin, and bovine serum albumin; T1: BM + 50 ng/ml EGF; T2: BM + 100 ng/ml FIL; T3: BM + 5 µg/ml ITS; and T4: BM + EGF, FIL, and ITS combined at the same concentrations. All groups were incubated for 24 hours. Cumulus expansion was evaluated by measuring cluster thickness before and after IVM, and nuclear maturation status was determined using Hoechst staining. Data were analyzed by ANOVA and the LSMEAN test. The addition of EGF, FIL, ITS, or their combination did not significantly affect the rate of nuclear maturation, which ranged from 16.3% to 24.8%, nor did it influence the proportion of immature or degenerated oocytes. However, cumulus thickness was significantly affected by treatment (P < 0.0001). In conclusion, while the supplementation of growth factors did not improve nuclear maturation in guinea pig oocytes, it did influence cumulus cell expansion during in vitro maturation.
Efecto de la bST aplicada al inicio de un programa superovulatorio con FSHp y al momento de la inseminación artificial sobre la respuesta ovárica y la producción de embriones transferibles en vacas mestizas
(2017) Bravo Mosquera, Sandra Elizabeth; Perea Ganchou, Fernando Pedro
Application of bovine recombinant somatotropin (bST) at the beginning of a superovulation treatment (SOV) increased the number of antral follicles that emerged in a follicular wave, improved the SOV response and increased the rate of embryos recovered. A study was conducted with the objective of evaluate the quantity and quality of embryos obtained in response to the application of bST in two strategic moments of an ovarian super stimulation treatment. A total of 40 crossbred cows with a body condition between 2.75 and 3 on the scale of 1 to 5, clinically healthy and without apparent reproductive alterations were used. The cows were treated with an intravaginal progesterone device for 6 days (Day 0, beginning of the treatment) and with 4 daily decreasing doses of FSH-p from day 4, divided into two daily IM injections (50, 40, 30, 20 mg of FSH  2). The females were randomly assigned to one of the following treatments: GH0 (control group; n=10) without bST; GH1 (n=10) a dose of 500 mg bST at day 0; GH2 a dose of rbST at the time of the first insemination (IA) (day 8); GH3 two doses of 500 mg bST, at day 0 and 8 of the treatment. The embryos were recovered by a non-surgical method, 7 days after the first AI (day 15). Ultrasonography showed that the control group had a greater number of corpora lutea than the groups treated with rbST (13.9 ± 9.2 versus 8.0 ± 4.0, 7.1 ± 3.6 and 9.0 ± 4.4 for GH1, GH2 and GH3 respectively, P>0.05). The total number of structures recovered (oocytes and embryos), degenerate embryos and unfertilized oocytes did not differ between treatments, although in all cases the coefficient of variation was considerably lower in GH3 and GH2 than in the other groups. The percentage of transferable embryos was statistically similar between treatments, ranging from 74.1% in GH0 to 80.2% in GH1, with intermediate figures in the other experimental groups. It was concluded that the application of bST at the start of treatment with SOV and / or at the time of AI did not improve the superovulatory response nor the number of transferable embryos recovered.
Efecto de la fase del ciclo estral en la maduración in vitro de ovocitos de gatas domésticas criadas en condiciones tropicales
(2023) Perea Ganchou, Fernando Pedro
Oocyte maturation is a critical step for in vitro embryo production. In female cats, findings on the influence of the estrous cycle stage on oocyte quality and maturation are contradictory. Little is known about this phenomenon in female cats in the tropics. This study aimed to assess the effect of the estrous cycle stage on oocyte quality and subsequent capacity to complete nuclear maturation in cats in a tropical environment. Ovaries from 18 sexually matured cats were collected during ovariohysterectomy. Cumulus–oocyte complexes (COCs) were released from follicles by slicing and fragmentation of the ovarian cortex. According to morphological characteristics, COCs were classified into grades I–II (suitable) and III–IV (no suitable). Only suitable COCs from each cat were cultured for in vitro maturation. Nuclear oocyte maturation was assessed by the presence of a telophase I or metaphase II plate with extrusion of the first polar corpuscle. A significantly greater number of oocytes per ovary were collected from queens in inactive than in follicular or luteal phase. Proportions of suitable COCs were similar among groups. Rate of oocyte maturation did not differ among stages of the estrous cycle, nor did the proportion of non–matured or degenerated oocytes. The age of the queens did not affect the percentage of oocyte maturation. In conclusion, the quality and rate of oocytes maturation were similar in the three stages of estrous cycle examined.
Efecto del ciclo lunar en algunas características morfológicas y funcionales del ovario en cobayas (Cavia porcellus)
(Universidad de Cuenca, 2024-07-24) Camas Carangui, Luz Isabel; Chabla Morquecho, Natalia Soledad; Perea Ganchou, Fernando Pedro
This study aimed to assess the influence of the lunar cycle (LC) on serum progesterone and estradiol concentrations, and follicular count in guinea pigs. Eighty nulliparous guinea pigs, aged 3-3.5 months and weighing 106190 g were randomly assigned to four time points (n=20 each; 5 animals per phase for 4 consecutive LCs) of the LC: new moon (NM); crescent quarter (CQ); full moon (FM); waning quarter (WQ). Animals were fasted for 12 hours and anesthetized with sevoflurane. In an unconscious state, blood samples were taken by cardiac puncture and the animals were immediately euthanized by cervical dislocation. Ovaries were removed and weighed, and one of them was histologically processed. Different categories of follicles in the whole ovary were counted by duplicate (two slices separated by 250 μm) under a stereoscope. Progesterone (P4) and estradiol (E2) concentrations were quantified by chemiluminescence. Data were analyzed by the general lineal model and the last square means test of SAS. Ovarian weight and gonadosomatic index were not influenced by moon phase. LC influenced serum P4 (P=0.0489) and E2 (P<0.0001) concentrations. Progesterone was greater (P<0.05) in NM (5  0.7 ng/ml) than in FM (2.6  0.7 ng/ml) and WQ (3.1  0.7 ng/ml). Estradiol was greater (P<0.0001) in NM (86.8  3 pg/ml) than in CQ (71.7  2.9 pg/ml), FM (77.1  2.9 pg/ml) and WQ (70.3  3 pg/ml). LC affected the number (P=0.0005) and percentage (P=0.0014) of large antral follicles (LAF). Number of LAF was greater in NM (3.0  0.49) than in CQ (2.0  0.48; P>0.05), FM (0.6  0.46) and WQ (0.8  0.49) (P<0.01). The number (P=0.0019) and percentage (P=0.0013) of primordial follicles (PF) were influenced by moon phase, with lower values in the number of PF in WQ (13.3  1.7) than in NM (18.8  1.6), CQ (20.3  1.6) and FM (22.5  1.5) (P<0.01). The number of corpora lutea and other follicular categories were similar among lunar phases. In conclusion, LC influenced circulating concentrations of ovarian steroids and the proportions of large and primordial antral follicles in guinea pigs.
Efecto del estadio del ciclo estral y de la categoría de los complejos cúmulo-ovocito (COC’s) sobre las características morfológicas y funcionales de ovocitos de cobaya (Cavia porcellus)
(Universidad de Cuenca, 2023-07-17) Pazmiño Rodríguez, Andrea Priscila; Pangol Araujo, Erika Fernanda; Perea Ganchou, Fernando Pedro
The objective was to evaluate the characteristics of cumulus-oocyte complexes obtained at different stages of the estrous cycle and their relationship with the morphological and functional characteristics of guinea pig oocytes. Forty guinea pigs aged 3 to 9 months were synchronized with REGUMATE® (0.22 mg/kg) for 15 days. After 2 and 10 days after progestogen withdrawal, the ovaries were collected and COC's were obtained by serial sections and classified into type A, B and C. Forty percent of the COCs were used to determine G6PDH enzyme activity and to measure the distribution of cytoplasmic lipid droplets, while the remaining 60% were used to measure cytoplasmic diameter and volume, to study nuclear progression and the rate of apoptosis. The BCB test evidenced a higher proportion of BCB+ oocytes in the periovulatory than in the diestrous. The distribution of lipid droplets in the cytoplasm was significant in the diestrous, observing that type A and C oocytes were similar in terms of uniform lipid distribution; whereas, type B oocytes, had a slightly higher percentage with central lipid distribution. In the apoptosis rate, there was a lower percentage in the periovulatory phase than in the diestrous phase. Nuclear status showed a higher percentage of mature oocytes in the periovulatory than in the diestrous. Oocyte diameter and volume showed that oocytes were significantly larger in the diestrous than in the periovulatory.
Effect of delayed addition of fetal calf serum to the culture medium on in vitro embryo production from creole heifers raised in a high altitude in Ecuador
(2024) Méndez Álvarez, María Silvana; Perea Ganchou, Fernando Pedro; Galarza Lucero, Diego Andrés; Galarza Alvarez, Luis Rodrigo; Argudo Garzon, Daniel Ernesto; Soria Parra, Manuel Elías
This experiment aimed to assess the effect of fetal calf serum (FCS) added to culture medium on day 5 to 7 after in vitro fertilization on production and subsequent cryotolerance of blastocysts from Ecuadorian Creole heifers. Immature cumulus-oocyte complexes (COCs) were collected by ovum pick-up (OPU) from 10 Creole heifers and from ovaries collected at abattoir in eight collection sessions. COCs were subjected to in vitro maturation (IVM), fertilization (IVF), and culture (IVC). On day 1 after IVF, presumptive embryos from each oocyte source (OPU [O] and Abattoir [A]) were allocated randomly in two groups according to whether 2.5% (v/v) FCS was added to culture medium on day 5 after IVF: 1) O-FCS+, 2) O-FCS-, 3) A-FCS+, and 4) A-FCS-. On day 7 after IVF, high quality embryos were vitrified. Cryotolerance of vitrified-warmed embryos was assessed according to blastocele re-expansion at 2 h and subsequent re-expansion and hatching at 24 and 48 h of re-incubation. Blastocysts rate on day 7 did not differ between oocyte source and FCS group. After vitrification/warming process, addition of FCS affected the re-expansion rate only at 2 h, irrespective of the oocyte source (p<0.05). Likewise, blastocysts hatching rate at 48 h of incubation was drastically affected only in OPUderived oocyte (p<0.01). Supplementation of FCS on day 5 after IVF did not improve blastocyst production and adversely affected the cryotolerance of in vitro bovine embryos derived from creole heifers raised on Ecuadorian Andean highlands.
Effect of dietary supplementation with mulberry (Morus alba) meal on the productive performance of growing quails (Coturnix coturnix japonica)
(2019) Perdomo, Daniel A.; Briceño, Ana; Díaz, Doraida; González, Diomary; González, Líber; Moratinos, Pedro A.; Núñez, Eliani K.; Perea Ganchou, Fernando Pedro
© 2019 Universidad Nacional Mayor de San Marcos. All rights reserved. The aim of this study was to evaluate the productive performance of growing quail (Coturnix coturnix japonica) fed with a commercial balanced feed and supplemented with mulberry meal (Morus alba). The experiment was carried out in Trujillo, Venezuela, for six weeks. A completely randomized design was applied with three treatments (diets) and five repetitions per treatment (4 birds per repetition). The diets were: T0: 100% commercially balanced feed (AB); T1: 90% AB + 10% of mulberry meal (HM); T2: 80% AB + 20% HM. The final body weight (FW), daily weight gain (DWG), feed consumption (DI), specific growth rate (SGR), feed conversion (FC), carcass yield (CY), mortality and cost-benefit ratio were determined (CB). The data were processed by analysis of variance using the GLM procedure of the SAS program. The FW and the DWG were higher in T1 and T2 (PF: T0: 139.1 ± 1.9, T1: 147.2 ± 2.0, T2: 147.1 ± 1.9, (p<0.03) (DWG: T0: 3.1 ± 0.05, T1: 3.3 ± 0.05; T2: 3.3 ± 0.05 (p<0.03). The birds of T1 and T2 consumed more feed than those of T0 (p<0.01). The SGR was lower (p<0.05) in T0 (7.01%) than in T1 (7.13%) and T2 (7.14%). FC and CY did not vary between treatments. The CB ratio favored the birds of T1 and T2. It is concluded that the addition of HM in the ration improved FW, DWG and CB, constituting an alternative to reduce the feeding costs of the commercial farms without diminishing the productive indices of the birds.