Browsing by Author "Narváez Terán, Jhonny Alfredo"

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Asociación analgésica de la ketamina con fentanilo y/o lidocaína en el dolor intraoperatorio de caninos hembras sometidas a ovariohisterectomía
(2019-03-27) Gómez Quito, Karina Maribel; Narváez Terán, Jhonny Alfredo
The research was carried out in the Teaching Veterinary Clinic of the University of Cuenca, with the aim of evaluating the intraoperative pain control by means of the use of an antagonist of the N-Methyl-D-Aspartate (NMDA) receptors in combination with a narcotic and / or a local anesthetic administered parenterally in bitches subjected to ovariohysterectomy. For this purpose, we used 30 bitches of 4-5 body condition, an age between 6 months to 3 years, different races and clinically healthy. There were applied three treatments each with 10 bitches randomly selected. The treatments consisted in the administration of an antagonist of NMDA receptors (ketamine) together with a narcotic (fentanyl) and / or a local anesthetic (lidocaine) 15 minutes before and during the surgery. T1: continuous infusion of ketamine (10 μg/kg/minute) and fentanyl (0.7 μg/kg/minute), T2: continuous infusion of ketamine (10 μg /kg/minute) and lidocaine (25 μg/kg/minute) and T3 was the witness treatment. In the anesthetic protocol was administered in the preanesthesia: acepromazine 0.1mg/kg IM (T3 + tramadol 2mg/kg IM), in the induction: propofol 3mg/kg IV and for maintenance: sevoflurane inhaled concentrations of 1.5-2.5%. To determine its effects on intraoperative pain, the following variables were measured: heart rate (HR), respiratory rate (RR), mean arterial pressure (MAP), and oxygen saturation (SPO2) (every 5 minutes during the procedure of the surgery). The normality of the data was evaluated using the Shapiro Wilk test, and for its respective analysis was used the Kruskal-Wallis test, with a confidence level of 95% (P <0.05). Findings demonstrated that the heart rate variable presented a significant difference, being 118.83 in T1, 110.09 in T2, and 120,79 in T3, being within the normal levels. Additionally, the other variables did not present significant differences. In conclusion, the treatments under study and the witness treatment regulates the pain in equal measure during the intraoperative period in ovariohysterectomy surgeries
Bases farmacológicas modernas de la terapia de la enteritis infecciosa de los terneros
(2009) Guamán Guamán, Lorena; Narváez Terán, Jhonny Alfredo
Comparación de la ozonoterapia y tratamiento alopático sobre la endometritis subclínica en vacas Holstein mestizas en periodo postparto
(2017) Maldonado Pauta, Hugo Marcelo; Enríquez Morocho, Manuel Marcel; Narváez Terán, Jhonny Alfredo
The objective of this study was to compare the effect of ozone therapy and an allopathic treatment on subclinical endometritis (SE) in Holstein cows in the postpartum period. The research was made in three dairy farms of Cuenca: Granja Nero and Granja Irquis of the University of Cuenca; and a private dairy farm, Cumbesa, since February to November 2016. Multiparous cows were selected between 34 and 47 days postpartum (DPP), they were practiced endometrial cytology, the cows with a percentage ≥ 10% of polymorphonuclear (PMNs) were considered with SE and were divided in two groups, they were applied through intrauterine to G1 (n = 30) with 500mg cephapirin benzathine (CB) excipient csp 19g, to G2 (n = 30) with 45μg / ml O3 in 60ml of distilled water sterile type II and in the group 3 (n = 30) was composed of cows with a percentage of PMNs <10% which did not receive any treatment (control group); the data were processed using a PROC GLIMIX general linear model of SAS 9.3. The percentage of PMNs between 34-47 DPP in G1, G2 and G3 were 16,3 ± 0,09; 15,1 ± 0,09 and 3,4 ± 0,19 respectively, after 72 hours the effect of the treatments was evaluated, obtaining statistical difference between G1 = 6,2 ± 0,04% and G2 = 3,2 ± 0,05% (P <0,0001), and G1 vs G3 (2,9 ± 0,05%) (P <0,0001). The interval between calving (IPCe), interval conception (IPCo) and the percentage of pregnancy at the first service did not present a statistical difference between the treatments (P> 0.05), however, in G2 we estimate to obtain higher lactation income ($ 13.218,10) compared to G1 ($ 8.925,06) due to a higher percentage of pregnancy to first service (63.3% and 43.3%, respectively) and lower costs in the IPCe and IPCo. In conclusion, the administration of O3 and CB reduce the percentages of PMNs between 34 and 47 DPP, O3 being more effective and has a positive economic impact on the reproductive performance compared to the other treatments under study.
Detección de antibióticos en canales bovinas faenadas en el camal municipal del cantón Azogues, Ecuador
(Universidad de Cuenca, DIUC, 2017) Villa Parra, María Gabriela; Vintimilla Rojas, Andrea Elizabeth; López Crespo, Gonzalo Estuardo; Andrade Guzmán, Omar Santiago; Narváez Terán, Jhonny Alfredo
La ganadería es una de las actividades pecuarias más antiguas y tradicionales, cuyo propósito es la producción de leche y carne, la población bovina en Ecuador es de 5.3 millones de cabezas, de esta cifra el 50.64 % está en la región Sierra, cuya principal actividad es la producción de leche. En la zona austral la carne proviene de los animales que se descartan de la industria lechera por diversos problemas sanitarios y reproductivos (INEC, 2011). En la actividad ganadera se usa una gran variedad de productos farmacológicos, dentro de los cuales están los antibióticos con el fin terapéutico de controlar enfermedades bacterianas. La mayoría de estos productos tienden a depositarse en órganos y tejidos de los animales tratados, constituyendo un grave riesgo para la salud de los consumidores, sobre todo cuando no se respeta el tiempo de retiro recomendado por el fabricante. Entre los efectos nocivos relacionados con esta práctica, se incluyen reacciones de hipersensibilidad, resistencia bacteriana, alteración de la microbiota intestinal, nefropatía y hepatotoxicidad (Rico & Ferraro, 1999). El Codex Alimentarius, es el punto de referencia internacional más importante en cuanto a los límites máximos permitidos de antibióticos expresados en μg kg-1, que pueden estar presente en tejidos de animales destinados al consumo humano, permitiendo asegurar la calidad e inocuidad de los alimentos (Codex, 2012). En los centros de faenamiento de la región austral del país por lo general no existe control ni regulación de la presencia de residuos de antibióticos en canales bovinas, debido a las dificultades técnicas que implican su detección y a la no aplicación de normas. De allí que el objetivo de esta investigación fue detectar la presencia de antibióticos en carne de bovinos faenados en el camal municipal de la ciudad de Azogues, mediante la prueba microbiana premi-test®. 2. MATERIALES
Efecto de la GnRH, benzoato de estradiol y ablación folicular en el tiempo de reinicio de la nueva onda folicular en vaconas Holstein Mestiza en fase luteal
(2019-02-26) Pesantez Duran, Jesús Alejandro; Supliguicha Merchan, Juan Daniel; Narváez Terán, Jhonny Alfredo
The objective of this study was to evaluate the effect of GnRH, estradiol benzoate and follicular ablation on the restart time of the new follicular wave in Holstein Mestiza vaconas in the luteal phase. The research was conducted in the Nero farm of the University of Cuenca with nine vaconas between 15 and 18 months of age, clinically healthy with a weight greater than 300 kg, and a CC of 3 on a scale of 1 to 5. The synchronization of the luteal phase of the vaconas was performed with the use of an intravaginal progesterone device, estradiol benzoate (BE) and prostaglandin (PGF), 56 hours after removal of the implant, the presence of the pre ovulatory follicle (FPO) was evaluated. On the 9th postapplication of PGF, the presence of a functional corpus luteum and dominant follicle was confirmed, and three treatments were applied, T1 (n = 3) Estradiol benzoate 2.5 mg IM, T2 (n = 3) GnRH 250 ug IM, T3 (n = 3) ablation of the follicles >5 mm in the first period, and in the same way in the following two periods alternating the treatments. To determine the restart time of the new follicular wave, the peaks of FSH in blood were related to the presence of the new cohort of recruited follicles; To measure FSH levels, a blood sample was taken from the jugular vein every 24 hours for 4 days after application of the treatments, and the presence of the new cohort of follicles was evaluated by ultrasound during 4 days post treatments. An experimental 3x3 Latin square design was used with three treatments and three repetitions in different periods. The administration of BE in this study caused the restart of the follicular wave at 3 days post treatment, with the application of GnRH this restart was evidenced at 2.33 days and by follicular ablation, the restart was verified at 2 days. The Duncan test determined that there is a significant difference (p<0.05) in the restart time of the three treatments used, grouping them into different homogeneous subsets. During the two pharmacological treatments, atresia of the dominant follicle was observed
Efecto de la grasa sobrepasante en el reinicio de la actividad ovárica y su relación con la glucosa y colesterol en vacas en período de transición
(2016) Ortuño Barba, Carlos Luis; Loja Pacho, Jaime Santiago; Narváez Terán, Jhonny Alfredo
and size of the corpus luteum (CL) and finally, body condition (CC) was evaluated. The results were analyzed with the statistical program SPSS version 22.0 and testing Shapiro Wilk and Levene was applied to analysis of Normality and Homogeneity, respectively, applying an ANOVA and "U-Man Whitney" test to establish significance. The best average glucose value for T2 (P<0.05) 56.9±1.52 mg/dl, however, cholesterol there was no difference (P>0.05) between groups was obtained. Existed in follicular size differences (P<0.05) with better results in T2 (9.7±0.30 mm), but the size of CL and P4 there was no difference (P>0.05), however, T2 cows showed better 52.7±3.68 IPPC days (P<0.05), ensuring that there is no correlation (P>0.05) between serum energy indicators and restarting the sexual cycle via the statistical Spearman Rho; finally in the CC also he showed a better average value T2 with 3.0±0.46 and periods (P <0.05). In conclusion, the addition of bypass fat in cows transition period reduces and increases IPPC serum glucose level, but does not alter cholesterol levels
Efecto de la ozonoterapia en el reinicio de la ciclidad ovárica durante el puerperio de vacas
(2013) Araujo Alvarracín, Johanna Maritza; Argudo Rivadeneira, Jaime Aurelio; Narváez Terán, Jhonny Alfredo
Efecto de ozonoterapia sobre las afecciones uterinas en vacas repetidoras
(2019-11-18) Romero Aguilar, Bryan Manuel; Narváez Terán, Jhonny Alfredo
The research was carried out at “Nero” and “Irquis” farms of the University of Cuenca and the private farm “El Carmen” in the Azuay province; the objective of the study was to evaluate the effect of ozone therapy on subclinical endometritis in repeat breeder cows (RBC), for this study a total of 42 RBC with subclinical endometritis (SE), multiparous with a body condition of 2.5 - 3; the diagnosis of SE was made by endometrial cytology considering positive those that present a percentage ≥ 5% of polymorphonuclear cells (PMN), in addition the diameter of uterine lumen in millimeters (mm) at the base of one of the uterine horns was evaluated by ultrasonography; subsequently, samples of uterine secretion were collected for the identification of bacterial agents; to then perform the intrauterine treatments, for G1 (n = 21) 500 mg of cephapirin benzathine was applied and G2 (n = 21) 45 ug of O3 was used in 50 ml of sterile bidistilled water; after 72 hours the effect of treatments was evaluated. The results were analyzed by basic statisticians, logistic regression and contingency tables, using INFOSTAT. The prevalence of SE in RBC during the study was 47.76%; in the G1 the PMNs decreased from 12.5 ± 0.99 to 6.5 ± 0.76% and for the G2 they showed a greater therapeutic effect 11.5 ± 1.19 to 4.0 ± 0.52%; the diameter of the uterine lumen was reduced in G1 from 2.23 ± 0.14 to 1.72 ± 0.08 and in G2 from 2.21 ± 0.12 to 1.62 ± 0.13 mm not differ between them; in relation to the presence of bacterial agents, 45.24% Staphylococcus spp., 9.5% Escherichia Coli, 7.4% Pseudomonas Spp., 9.5% Bacillus spp., and 38% of the samples did not show isolation bacterial; the percentage of pregnancy reached was 33.0% in G1 and 48.0% for G2 they did not express differences (P> 0.05) but manages to recover fertility. In conclusion, intrauterine administration of benzathine cefapirin and ozone reduces the diameter of the uterine lumen; however, ozone proved to be better in PMN reduction than allopathic treatment (benzathine cefapirin).
Efecto del benzoato de estradiol en la morfometria del foliculo y cuerpo lúteo en vacas holstein sincronizadas con D-Cloprostenol
(2013) Soria Parra, Manuel Elías; Narváez Terán, Jhonny Alfredo
Eficacia de tres prostaglandinas de uso comercial (lliren, glandin N y Syncrocept B) en aplicación intrauterina para la sincronización del celo en vaconas
(1990) Narváez Terán, Jhonny Alfredo; Jetón S., Patricio; Soria Parra, Carlos Alonso
Eficacia farmacológica de la infusión intramamaria de agentes antimicrobianos (bactericidas y bacteriostáticos) en el período de secado
(Universidad de Cuenca, 2025-08-06) Ortiz Sibri, Janneth Cristina; Pulgarín Macas, Daniela Jacqueline; Narváez Terán, Jhonny Alfredo
Subclinical mastitis is one of the main causes of economic losses in dairy production, due to its negative effect on reduced milk production and increased veterinary expenses. The objective of this study is to evaluate the efficacy of bactericidal (cloxacillin) and bacteriostatic (lincomycin) antimicrobial agents by intramammary infusion in the elimination of subclinical infections during the dry-off period. Sixty mammary quarters from cows diagnosed with subclinical mastitis were analyzed at two points in time (first 15 days of the dry-off period and 7 days postpartum). Among the bacteria identified in the samples were Escherichia coli (23.33%), Staphylococcus spp. and Streptococcus spp. (85% together), in addition to Gram-positive (3.34%) and Gram-negative (5%) bacilli. In terms of antimicrobial sensitivity, cloxacillin showed 40% sensitivity against the isolated strains, while lincomycin reached 36.67%. Cloxacillin was more effective against Staphylococcus spp. than lincomycin (34.38%), while lincomycin showed better results against Streptococcus spp. (28.57%). Likewise, both drugs achieved 100% efficacy against Escherichia coli. However, both treatments showed limited efficacy against Gram-positive bacilli. These results suggest that the use of bactericidal antimicrobials during drying offers better results in the prevention and control of bacterial infections.
Eficiencia técnica en granjas lecheras de la sierra andina mediante modelación con redes neuronales
(2019) Torres Inga, Carlos Santiago; López Crespo, Gonzalo Estuardo; Guevara Viera, Raúl Victorino; Narváez Terán, Jhonny Alfredo; Serpa García, Víctor Guillermo; Guzmán Espinoza, Clelia Kathrine; Guevara Viera, Guillermo Emilio; Aguirre De juana, Angel Javier
Aim: The aim of this work was to estimate the efficiency of milk production in 1 168 cases in Ecuadoran Sierra Sur Andina, with the implementation of neural networks with multilayer perceptrons. Materials and Methods: These cases were collected from secondary samples provided by the Official Institute of National Statistics of Ecuador, in 2016. The variables chosen for the model were total milk production on the previ-ous day (P), as dependent variable; and total cattle heads (CH), total laborers in the field (E), and total surface at-tended by laborer (S), as independent variables. The selection criteria were the existence of data from individual cas-es, and their impact on the dependent variable. Results: The average efficiency was 8.11 %, from which the total cases detected efficiently (> 0.70) accounted for 11 (0.9 % of the sample). Later, the cases studied were classified into three groups, depending on the efficiency calculated: Group 1 (≤ 0.4 efficiency); Group 2 (> 0.4 - ≤ 0.7 efficiency); and Group 3 (> 0.7 efficiency). Conclusion: A comparison produced several statistical differences (P < 0.01) for variables total milk production/year on the farm, total field laborers, farm size, total cows, total cattle heads, calvings, pregnant cows, and served cows.
El empleo de la HCG y PMSG para la introducción de la superovulación y producción espermática en trucha Arco Iris en la zona del Cajas
(2013) Auquilla Prado, Adriana del Carmen; Maldonado Guerrero, Celia Leonor; Narváez Terán, Jhonny Alfredo
El empleo de la ozonoterapia como alternativa de tratamiento en vacas con endometritis durante el puerperio
(2014) Alvear León, Oscar Leonel; Narváez Terán, Jhonny Alfredo
This research work on "THE USE OF OZONE AS ALTERNATIVE TREATMENT IN COWS DURING ENDOMETRITIS PUERPERIUM" took place in the province of Azuay in Cuenca and the cantons of Victoria of Portete and Chicán respectively. This research had as its object, the application of ozone therapy for the treatment of endometritis in cows compared to traditional allopathic treatments. 60 cows were used, endometritis diagnosed between 21 and 30 days postpartum, with different ages, one ozonificadora machine together with an oxygen tank, syringes 50ml, 0.9% sodium chloride wash rigid intrauterine catheter, cephapirin benzathine. 3 groups of 20 animals each were formed; the first group 500mg benzathine cephapirin was applied in a single application with intrauterine and the second and third groups, saline and ozone gas (O3), respectively, 50mL each intrauterine route, at a concentration of 32μg / ml of oxygen at a volume of fluid between 3.5 to 4 L with an ozonizer device. No difference (P> 0.05) was found in the comparison of means between variables treatment, percentage of positive treatment, return to the cycle in days, pregnancy percentage, percentage of repeat breeders. Both the application of ozonated saline, ozone gas (O3) and cephapirin benzathine reached equally effective for the treatment of puerperal endometritis. Considering the economic analysis it was established that the treatment with ozone gas turned out to be a treatment of choice at lower cost than the commercial product. The use of ozone is very advantageous within the herd, because it is economical; it is a non-residual product and friendly to the environment
Estructura del pastizal, producción de leche y emisión de metano en vacas lecheras en pastoreo
(2021) Ortuño Barba, Carlos Luis; Faican Faican, Rosa Paola; Carangui Quintuña, Angel Bernardo; Cabrera Vazquez, Luis Geovanny; Guevara Viera, Raúl Victorino; Angamarca Padilla, María Alexandra; Patiño Puma, Paola Andrea; Narváez Terán, Jhonny Alfredo; Guevara Viera, Guillermo Null; García Zumalacarregui, Jorge Alejandro; Arcos Álvarez, Cristian Neptali; Lascano Armas, Paola Jael
The research was carried out at the IrquisExperimental Farm belonging to the University of Cuenca, Azuay province, Ecuador, at 2,663 meters above sea level with the following coordinates 1773890 E and 9659302 N, it is temperate climate, temperature between 8 and 14 ° C, relative humidity 80% and a rainfall of 639 mm / year. The research was carried out during 16 weeks, between the months of December 2018 to March 2019. The animal response was determined as milk production based on three botanical composition patterns, with a predominance of Kikuyo, in another with a predominance of Ryegrass and in another with an Association of these and White Clover. The structure of the grasslands was determined. The availability of forage was similar between the different types of grasslands, due to the time of study and that the components measured in the grassland had a compensatory effect, likewise the utilization in the Kikuyo pastures and the Ryegrass-Treból Association was better compared to Ryegrass. Milk production was higher in Kikuyo, most likely due toits better structure.
Evaluación cuali-cuantitativa de semen colectado con electroeyaculador (EE) de toros tratados con y sin tranquilizante
(2017) Brito Tene, Diana Maricela; Reinoso Chacón, Nancy Yolanda; Narváez Terán, Jhonny Alfredo
The objective of this research was to improve the conditions of seminal collection with Electroeyaculador (EE), trying above all to preserve animal welfare during the collection process. It was performed with three adult bulls of Criollo phenotype, in two different situations: T1- without tranquillizer and T2- with tranquilizer (xylazine 2%) applied prior to collection. The semen was collected during 9 sessions, adding a total of 27 collections. To determine the effect of the tranquilizer during the seminal extraction, two stress indicators were evaluated; Cortisol and progesterone by means of blood samples taken at five moments: 20 and 5 minutes before, at the time of collection and 5 and 20 minutes after the collection, and also by means of fecal samples. In addition, qualitative and quantitative seminal characteristics were analyzed; Then processed, frozen and evaluated post-thawing in order to evaluate the effect of the tranquilizer. Fresh seminal analysis was not significant (P> 0.05) when comparing treatments, but in post-thawing if there were differences (P <0.05) for the HOST variable. Serum levels of cortisol showed significant differences at 5 minutes before and 5 minutes after collection, for P4 there were differences at 5 minutes after collection. These two hormones, when analyzed in feces at 8 hours after electroejaculation, were statistically different when comparing treatments. In conclusion, the use of xylazine does not improve the semen characteristics, however it decreases the stress generated after the process of electroejaculation in bulls.
Evaluación de la función ovárica y del perfil metabólico en vacas lecheras suplementadas con grasa sobrepasante en el periparto
(2017) Ortuño Barba, Carlos Luis; Narváez Terán, Jhonny Alfredo; Loja Pacho, Jaime Santiago; Maldonado Pauta, Hugo Marcelo; Enriquez, Me; Andrade Guzmán, Omar Santiago
En vacas lecheras, durante el periparto, ocurren cambios importantes en los niveles nutricionales y metabólicos. La demanda de energía para mantener la condición corporal, las funciones productivas y reproductivas, exceden la cantidad de energía que se obtiene de la dieta, y como consecuencia los animales entran en un balance energético negativo (BEN) (Butler, Pelton, & Butler, 2006). El BEN se relaciona con el retardo en el reinicio de la actividad cíclica del ovario en el posparto y provoca cambios en las concentraciones de metabolitos y de hormonas relacionadas con el metabolismo energético (Wadhwa, Grewal, Bakshi, & Brar, 2012). Es común utilizar grasas tratadas para cubrir las demandas nutricionales asociadas al BEN (Espinoza-Villavicencio, Ortega-Perez, Palacios-Espinoza, & Guillen-Trujillo, 2010), estas son inertes y no interfieran con el proceso de fermentación ruminal (Butler et al., 2006). Además, estas grasas suministran energía adicional para el animal luego de ser digeridas eficientemente en el primera porción del intestino delgado (Aguilar-Pérez, Ku-Vera, & Gansworthy, 2009; Sirohi, Walli, & Mohanta, 2010). Esta energía de la suplementación lipídica contrarresta el BEN, lo que favorece el crecimiento folicular, la primera ovulación y el restablecimiento de la función luteal, reduciendo el intervalo entre el parto (IEP) (Salas Razo, Herrera Camacho, Gutierrez Vasquez, Ku-Vera, & Aké- López, 2011). Los cambios bioquímicos del BEN se reflejan en la variación de los niveles de glucosa y colesterol, que pueden ser utilizados como un indicador confiable del balance energético y nutricional de la vaca lechera al inicio de la lactancia (Ceballos, Gomez, Vélez, Villa, & López, 2002). El objetivo de esta investigación es evaluar el efecto de la grasa sobrepasante en el reinicio de la actividad ovárica y su relación con indicadores metabólicos en vacas lecheras durante el periparto
Evaluación de la resistencia bacteriana a los antibióticos en muestras de heces, obtenidas de cobayos (Cavia porcellus) en explotaciones de tipo familiar y familiar- comercial
(Universidad de Cuenca, 2023-01-16) Vázquez Ramón, José Luis; Padilla Angamarca, Fernando Martin; Narváez Terán, Jhonny Alfredo
The inappropriate use of antimicrobial agents in guinea pigs to control enteric pathogens affects the food sustainability of the rural population, therefore it is important to identify the pathogen, its resistance and the appropriate antimicrobial agent for its control. The present investigation was carried out in family and family- commercial guinea pig farms in 8 rural parishes of the Gualaceo canton, province of Azuay, Ecuador, from where 384 samples were obtained by rectal swab of guinea pigs from production units with enteric problems (diarrhea), that were transferred to the laboratory of the Faculty of Agricultural Sciences of the University of Cuenca, where the culture media infection and identification of the pathogenic agents present were carried out, which were later exposed to an antibiogram, in order to qualitatively evaluate their resistance. bacterial. The data obtained were tabulated and analyzed, where based on the frequencies, a greater presence of Escherichia coli (49.4%) was found, followed by Salmonella typhimurium (24.6%), Shigella flexneri (14.3%) and Klebsiella pneumoniae (11.7%). In the chi 2 test, it was found that, of the five antimicrobials used, only one of them has a relationship (Tetracycline), between the bacterial presence and their respective resistance. It was also found that Escherichia coli presented a higher percentage of resistance compared to other bacteria, towards Enrofloxacin 22.5%; Neomycin 14.2%; Sulfamethoxazole – trimethoprim 33.3%; Tetracyclines 29.2%, data that were analyzed at a confidence level of 95% with a 5% error, concluding that the pathogens identified have low resistance to the antimicrobials used, but are still susceptible.
Evaluación de la validéz de la cría y análisis de semen para predecir la fertilidad del toro
(2011) Vera Castillo, Cristian Augusto; Narváez Terán, Jhonny Alfredo
Evaluación de la variabilidad de la respuesta superovulatoria en hembras bovinas donantes
(2009) Guachizaca Uyaguari, Jenny María; Narváez Terán, Jhonny Alfredo