Ciencias Agropecuarias
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Item Evaluación de la producción del cultivo de lechuga de hoja (Lactuca sativa), y el desarrollo de la Tilapia (Oreochromis niloticus) en el Sistema de Acuaponía.(Universidad Técnica de Ambato Ingenieria de Agronomíca, 2026-07) Sánchez Chuquitarco, María Fernanda; León Gordón, Olguer AlfredoAquaponics is a sustainable production system that combines fish and vegetable production in water, with low costs and high profitability rates. It is an activity that includes organic waste from food that was not ingested by fish, feces and urine of aquatic beings that with bacterial action are transformed into nitrates, benefiting plant development. This research was carried out with the objective of evaluating the production of leaf lettuce (Lactuca sativa) and the development of tilapia (Oreochromis niloticus) in the aquaponics system. For the development of the research, a completely randomized experimental design with 3 treatments and 3 replications was used. The population density of tilapia was the factor under study, which was 10, 15 and 20 tilapia/m3. In this study, the development of lettuce cultivation in an aquaponics system using tilapia as a fish species was evaluated. It was determined that treatment T3 (20 fish) yielded the best results in terms of weight, height of the lettuce plant, and yield. The results of the experiment indicate that growing plants with tilapia is feasible because it allows for the utilization of nitrogenous waste, as well as the cultivation of lettuce, which is of commercial interest. The aquaponic cultivation system makes available space more efficient and generates similar or higher yields than traditional cultivation. We can indicate that no statistical differences were observed in the parameters studied when raising tilapia (Oreochromis niloticus) in aquaponics. This is probably due to the fact that fish development is determined by factors such as temperature and feed, which were similar in all treatments.Item Comparación de tres protocolos anestésicos para orquiectomía y ovariohisterectomía en gatos con temperamento agresivo(Universidad Técnica de Ambato Maestría En Medicina Veterinaria, 2026-07) Guerrero Apo, Walter Rolando; Almeida Secaira, Roberto IsmaelSurgical sterilization through orchiectomy and ovariohysterectomy is one of the most commonly performed procedures in feline medicine. However, anesthetic management in aggressive cats remains challenging due to stress, difficulties associated with handling, and the risk of perioperative physiological disturbances. The present study was conducted to compare the efficacy of three anesthetic protocols in aggressive cats undergoing surgical sterilization. A total of 48 cats treated in the mobile urban animal control units of the Municipal Government of Ambato were included and assigned to three treatment groups: dexmedetomidine 5 µg/kg + ketamine 2 mg/kg + diazepam 0.4 mg/kg (T1); dexmedetomidine 5 µg/kg + tiletamine-zolazepam 4 mg/kg (T2); and xylazine 2 mg/kg + ketamine 2 mg/kg + midazolam 0.2 mg/kg (T3). Physiological parameters, anesthetic quality, and postoperative analgesic effects were assessed using the Feline Grimace Scale. The results emonstrated that all three protocols allowed the surgical procedures to be performed safely while maintaining acceptable physiological stability. Nevertheless, the protocols containing dexmedetomidine exhibited superior anesthetic induction and recovery characteristics, as well as lower facial expressions associated with postoperative pain. In contrast, the xylazine-based protocol showed greater variability during recovery and lower analgesic efficacy during the late postoperative period. It is concluded that dexmedetomidine-based protocols constitute effective and safe alternatives for the anesthetic management of aggressive cats, promoting smoother recovery and improved animal welfare.Item Evaluación de diferentes dietas ácido-básicas sobre la salud renal en conejos (Oryctolagus cuniculus)(Universidad Técnica de Ambato Maestría En Medicina Veterinaria, 2026-07) Tello Arellano, Augusto Iván; Villavicencio Villavicencio, Blanca JeanethRenal health in rabbits is closely related to the nutritional composition of the diet; therefore, prolonged alterations in dietary composition can modify the physicochemical characteristics of urine and predispose rabbits to urinary and renal disorders. In this context, the objective of this study was to evaluate different acid-base diets and their effect on renal health in rabbits (Oryctolagus cuniculus). The study used 36 mixed-breed rabbits, randomly assigned to four dietary treatments: a control group fed commercial concentrate and alfalfa ad libitum (T0); a group supplemented with sugarcane molasses (T1); a group supplemented with sugarcane molasses and citric acid (T2); and a group supplemented with sugarcane molasses and calcium carbonate (T3). Physicochemical and microscopic evaluations of urine were performed using reagent strips and urinary sediment analysis, in addition to serum urea and creatinine determinations. Complementary renal histological studies were carried out using hematoxylin-eosin, PAS, and Masson’s trichrome stains. Finally, a cost-benefit analysis was performed for each treatment. The diets evaluated caused changes in urinary characteristics and in some biochemical indicators related to renal function. The acidifying and alkalinizing treatments produced variations in urinary pH, specific gravity, and the presence of mineral sediments. Histologically, mild alterations compatible with renal metabolic adaptation were observed. From an economic standpoint, all treatments were viable; however, supplementation with sugarcane molasses showed the best cost-benefit efficiency. Dietary treatments were associated with descriptive changes in several urinary and histological indicators; however, no significant differences were detected in urinary pH or urine specific gravity. Our findings suggest that prolonged imbalances could promote subclinical alterations of the urinary tractItem Evaluación de la resistencia de Proteus mirabilis a Quinolonas y Betalactámicos y su relación con factores de virulencia(Universidad Técnica de Ambato Maestría En Medicina Veterinaria, 2026-07) Borja Ramos, Alva Tatiana; Cruz Quintana, Sandra MargaritaAntimicrobial resistance is a growing threat to public health, veterinary medicine and food safety. Proteus mirabilis is an opportunistic Gram-negative bacillus recognized for its occurrence in animals, animal-derived foods and environments associated with the food chain. The aim of this study was to evaluate the resistance of P. mirabilis isolated from chicken meat to quinolones and β-lactams, and to determine its relationship with virulence factors of clinical, veterinary and epidemiological importance. The study was conducted using a non-experimental, cross-sectional and descriptive design. A total of 41 P. mirabilis strains preserved at the Microbiology and Molecular Biology Laboratory of the Universidad Técnica de Ambato were analysed. These strains originated from registered and non-registered retail outlets in Ambato canton. Resistance genes were detected by PCR: gyrA and aac (6’)-Ib-cr, associated with quinolone resistance, and blaTEM and blaCTX-M, associated with β-lactam resistance. The amplified products were visualised by agarose gel electrophoresis. In addition, virulence factors were assessed through haemolysis on blood agar and swarming motility. The results showed high frequencies of resistance genes. The gyrA gene was detected in 85.37% of the isolates and aac (6’)-Ib-cr in 80.49%. Regarding β-lactams, blaTEM was identified in 80.49% and blaCTX-M in 58.54% of the strains. These findings demonstrate that chicken meat may act as a reservoir of P. mirabilis carrying genetic determinants of antimicrobial resistance. The coexistence of resistance genes with haemolysis and swarming suggests a potential health risk; therefore, strengthening molecular surveillance, food safety measures and the rational use of antimicrobials under the One Health approach is recommended.Item Cicatrización de heridas con la técnica Mölndal (ambiente húmedo) en comparación a la cicatrización convencional(Universidad Técnica de Ambato Maestría En Medicina Veterinaria, 2026-07) Alejandro Cuenca, Jonathan José; Lozada Ortiz, enny PiedadSurgical wound healing is a complex biological process that can be influenced by postoperative management strategies aimed at promoting tissue repair. The use of polyurethane dressings has shown positive outcomes because they maintain a moist and protected environment that supports more efficient healing. The objective of this study was to evaluate the effect of polyurethane dressings on wound closure, scar- related changes assessed using the Vancouver Scar Scale, and the persistence of the cardinal signs of inflammation (Celsus' signs) in canine patients undergoing reproductive surgeries. The study was conducted in clinically healthy canine patients assigned to two experimental groups: one treated using the Mölndal technique with a polyurethane dressing and the other managed without wound coverage. Evaluations were performed on postoperative days 0, 4, 7, 10, and 15 through measurement of residual wound length, application of the Vancouver Scar Scale, and assessment of the cardinal signs of inflammation. The results showed that wounds treated with dressings exhibited a significantly shorter residual wound length on postoperative day 4 (p = 0.005), indicating faster wound closure during the early phases of healing. Likewise, the total Vancouver Scar Scale score was significantly lower in this group on day 4 (p = 0.025), mainly due to reduced local vascularization. The presence of Celsus' signs was significantly associated with treatment on days 4 (p = 0.010) and 7 (p = 0.042), with a more rapid resolution of inflammation observed in animals treated with dressings. The use of polyurethane dressings promoted earlier surgical wound closure and reduced the persistence of inflammatory signs during the initial phase of wound healing.Item Bacillus subtilis y calidad del huevo en gallinas en postura tardía: una revisión sistemática(Universidad Técnica de Ambato Carrera de Medicina Veterinaria, 2026-07) Silva Gaspata, Silvia Maribel; Núñez Torres, Oscar PatricioPhysiological aging in late-phase laying hens affects egg quality and represents a challenge for the sustainability of poultry production. To compile available scientific evidence on the use of Bacillus subtilis as a probiotic to improve egg quality in late-phase laying hens. A quantitative systematic review was conducted using information obtained from scientific articles published between 2018 and 2026 in high-impact databases, following PRISMA criteria and search strategies with Boolean operators. Variables related to egg quality, intestinal morphometry, cecal microbiota, and enzymatic activity were analyzed. The analyzed studies showed increased villus height (1343±1045), reduced crypt depth (206±114), and improved villus height/crypt depth ratio (VH/CD) (6.25±1.89); an increase in beneficial bacteria such as Lactobacillus (28%) and a reduction in pathogenic bacteria (40%) such as E. coli, Clostridium, and Salmonella; as well as improvements in eggshell thickness (0.39±0.0373), shell strength (38.6±0.546), egg weight (62.1±4.98), Haugh units (81.3±10.1), and yolk color (7.42±1.96). Supplementation with B. subtilis constitutes a promising strategy to improve the internal and externalItem Evaluación de extracto etanólico microencapsulado de semillas de (Carica papaya) en comparación con Zinaprim sobre la excreción de ooquistes de Eimeria spp., digestibilidad aparente, signos clínicos digestivos y parámetros bio-productivos en conejos de ceba (Oryctolagus cuniculus)(Universidad Técnica de Ambato Carrera de Medicina Veterinaria, 2026-07) López Enríquez, Damaris Micaela; Díaz Sjostrom, PedroCoccidiosis in fattening rabbits is one of the main digestive diseases that limits rabbit production, as it affects nutrient absorption, reduces growth, and promotes diarrhea and other intestinal disorders. Given the conventional use of chemical anticoccidials, there is a need to evaluate natural alternatives that contribute to disease control and reduce dependence on pharmaceuticals. In this context, the present research aimed to evaluate the effect of microencapsulated ethanolic extract of Carica papaya seed, compared to Zinaprim, on the excretion of Eimeria spp. oocysts, apparent digestibility, digestive clinical signs, and bio-productive parameters in fattening rabbits. The study was conducted using a completely randomized design, with 40 rabbits distributed into four treatments: Control, Zinaprim, Carica papaya 50 mg, and Carica papaya 100 mg. Oocyst counts per gram of feces, presence of diarrhea, cecotrophy alterations, apparent digestibility, feed intake, feed conversion ratio, final weight, and average daily gain were evaluated. The results suggested that the treatment with Carica papaya 50 mg resulted in lower oocyst excretion on day 21 and a lower frequency of diarrhea, demonstrating a favorable effect against Eimeria spp. Apparent digestibility showed a higher trend in the group treated with Zinaprim, while the bio-productive parameters did not show statistically significant differences; however, the 50 mg treatment showed the best numerical values for final weight, weight gain, and average daily gain. These findings suggest that the microencapsulated ethanolic extract of Carica papaya seeds, especially at 50 mg, constitutes a promising natural alternative to reduce parasite load and improve digestive stability without negatively affecting the productive performance of rabbits.Item Evaluación de tres bioestimulantes mediante endoterapia en Persea americana, en sector Las Viñas, parroquia Picaihua, provincia de Tungurahua(Universidad Técnica de Ambato Carrera de Agronomia, 2026-07) Morales Morales, Mauro David; Velástegui Espín, Giovanny PatricioAvocado (Persea americana) cultivation represents a key economic alternative in the inter-Andean region of Ecuador; however, its productivity in the Tungurahua province is limited by acidic andosol soils that fix essential micronutrients, reducing the efficacy of conventional fertilization. Faced with this problem, the present applied research with a quantitative approach aimed to evaluate the efficacy of three foliar biostimulants (Algeed Plus, Kelpak, and Turbo Mix) at different concentrations (5 and 10 ml/L) applied via plant endotherapy to optimize fruit sizing. The methodology employed a Randomized Complete Block Design with a factorial arrangement (3x2 + 1 control), with three replications, in the Las Viñas sector, Picaihua parish. The response variables evaluated at 25 and 50 days were fruit diameter and weight. The results demonstrated highly significant differences (p < 0.0001), highlighting the Algeed Plus treatment at 10 ml/L as the most effective, achieving an average weight of 502.0 g and a diameter of 8.04 cm, surpassing the control by 87.1% and 11.7%, respectively. As a scientific novelty, this study validates endotherapy as a superior nutritional administration pathway that avoids edaphic fixation, offering a technically and economically profitable proposal for small and medium-sized producers in the Ecuadorian sierra, ensuring sustainable agronomic management.Item Aplicación de extracto de ajo ozonizado para el control de paratrioza (Bactericera cockerelli) en el cultivo de papa (Solanum tuberosum) en el Cantón Mocha(Universidad Técnica de Ambato Carrera de Agronomia, 2026-07) Freire Bonilla, Edith Scarlet; Zurita Vásquez, José HernánPotato cultivation (Solanum tuberosum) is a fundamental socioeconomic pillar for food security in the Ecuadorian Andean region; however, its productivity faces critical challenges due to the psyllid Bactericera cockerelli, the vector of the phytoplasma responsible for "purple top" disease, which can cause yield losses of nearly 100%. Given the urgent need to reduce reliance on synthetic agrochemicals, this research— framed within the line of sustainable phytosanitary management—evaluated the efficacy of ozonated garlic extract in controlling this pest in the Mocha Canton. A Randomized Complete Block Design (RCBD) with a factorial arrangement (2x2+1) was used, comparing doses of 2.5 cc/L and 5 cc/L against application frequencies of 8 and 15 days. The incidence of eggs, nymphs, the presence of phytoplasma in tubers, and total yield were quantified. The scientific novelty lies in the application of ozonolysis to stabilize the secondary metabolites of garlic, forming highly reactive ozonides that enhance its insecticidal and repellent action against sedentary stages of B. cockerelli. Results indicated that the most effective treatment was D1F1 (2.5 cc/L every 8 days), followed by D2F2. Compared to the control group, these treatments showed a lower population incidence and greater crop stability, establishing that the application of 2.5 cc/L every 8 days constitutes the most efficient technical strategy under local conditions. This proposal confirms that the ozonation of plant extracts optimizes phytosanitary control, offering an innovative, economically viable, and environmentally responsible solution that guarantees tuber quality in the face of pesticide pressure.Item Evaluación de sustratos para el trasplante de mora de castilla (Rubus glaucus Benth.) en Pelileo(Universidad Técnica de Ambato Carrera Agronomia , 2026-07) Barrera Castro, Wilman Joel; Villacis Aldaz, Luis AlfredoThe objective of this study was to evaluate the effect of four substrate types on the initial transplanting of Castilla blackberry (Rubus glaucus Benth.) seedlings into nursery bags in order to improve plant growth prior to field establishment in Pelileo and to identify the substrate mixture with the best agronomic performance under local agroecological conditions. The experiment was conducted at an altitude of 2912 m above sea level using a Randomized Complete Block Design (RCBD) with four treatments and three replications, resulting in a total of twelve experimental units. The evaluated substrates were: T1 = 100% commercial peat, T2 = 100% leaf litter, T3 = 40% black soil + 30% rice husk + 30% organic matter, and T4 = 100% local soil (control). The variables assessed at 45 and 60 days after transplanting were plant height, stem diameter, number of leaflets, and chlorophyll content. Data were subjected to analysis of variance (ANOVA), and mean comparisons were performed using Tukey's test at the 5% significance level. The results showed significant and highly significant differences among treatments for plant height, number of leaflets, and stem diameter. Treatment T1 (100% commercial peat) exhibited the best performance, reaching 21.27 cm in plant height, 26.33 leaflets, and 3.00 mm stem diameter at 60 days after transplanting. Treatments T2 and T3 showed statistically similar values, whereas T4 presented the lowest agronomic performance.