Journal of Agricultural Research

EVALUATION OF TWO COMMERCIAL EXTENDERS FOR FREEZING BOVINE SEMEN UNDER FIELD CONDITIONS

Reinaldo De Armas. , Andrick Camaño. , Neftalí Aparicio. , Reynaldo Vargas — Fri, 06 Jun 2025 00:00:00 +0000

The effect of two commercial semen extenders—Optidux (liposome-based) and Triladyl (egg yolk-based)—on post-thaw sperm quality and functionality parameters was evaluated. Semen was collected from a crossbred bull (F1 Simmental × Gyr) using electroejaculation, with three collections performed at four-day intervals. The dilution ratio used was 1:3. Equilibration was conducted in a FOAM container with ice for three hours at 4 ^°C. For each collection, ten 0.5 ml straws per extender were frozen, and each set was considered a replicate. Cryopreservation was initiated by exposing the straws to liquid nitrogen vapor for 15 minutes before immersion in liquid nitrogen. Post-thaw semen (thawed for 30 seconds at 35 ^°C) was evaluated for total and progressive motility, vigor, viability, and morphological abnormalities. These parameters were assessed at 0 and 2 hours of incubation. Statistical analysis was performed using the Chi-square test. Significant differences (p<0.02) were observed in sperm viability, with Triladyl® showing superior performance (32% viability at 0 hours post-thaw). Although viability decreased at 2 hours, Triladyl remained the most effective extender (p<0.007). In conclusion, both Optidux and Triladyl provided comparable in vitro results for post-thaw semen quality, suggesting that both liposome- and egg yolk-based extenders effectively mitigated structural damage during the freezing–thawing process, thereby preserving sperm motility.

DIVERSITY OF FUNGI ASSOCIATED WITH HIVES OF Apis mellifera (Hymenoptera: Apidae)

Fri, 06 Jun 2025 00:00:00 +0000

Fungal infections are one of the most important emerging problems for the health of bee colonies. To identify the fungal species, present in Apis mellifera hives, and thus recognize if they constitute a problem in the apiaries of the region, two fungal samples were taken in three randomly selected hives, belonging to three apiaries in the province of Chiriqui (San Lorenzo, Los Algarrobos and Potrerillos), during the rainy and dry seasons. The fungi were isolated from the following sites: wall and bottom of the hives (PF), worker larvae (LO), worker pupae (PO), drone larvae (LZ), and drone pupae (PZ). This study will serve as a baseline for identifying fungi present in Apis mellifera hives in Panama. The fungal species identified in the hives were: Aspergillus terreus, Aspergillus flavus, Aspergillus niger, Aspergillus caespitosus, Penicillium citrinum, Penicillium decumbens, Penicillium chrysogenum, Penicillium comunne, Fusarium oxisporum, Fusarium chlamydosporum, Cladosporium herbarum, Cladosporium cladosporioides, Chrysonilia sitophila, Curvularia lunata, Rhizopus stolonifer, Beauveria bassiana and Paecylomices javanicus. B. bassiana and P. javanicus were considered important entomopathogens. The species varied by season and hive conditions, registering the genera Aspergillus as the most abundant and frequent in the three sampled sites. The fungal species diversity indices of Shannon-Wiener were San Lorenzo 'H= 1.69, Los Algarrobos 'H= 2.18, and Potrerillos 'H= 2.40. The sampled apiaries showed acceptable infections by fungi that come mainly from the host plants that are visited by honeybees.

APPLICATION OF THE EXTRACT OF Artocarpus Heterophyllus IN THE OPTIMIZATION OF THE FERMENTATION PROCESS IN TWO

Luis Vásquez. , Álvaro Pazmiño. , María Cabanilla. — Fri, 06 Jun 2025 00:00:00 +0000

Cocoa is one of the most important raw materials worldwide and serves as the economic backbone for many small and medium-sized farmers. This study aims to evaluate the use of Jackfruit extract (Artocarpus heterophyllus) in the fermentation of cocoa, a crucial process that impacts the physical and sensory quality of the final product by influencing the removal of mucilage and the chemical changes in cocoa. A completely randomized bifactorial design was employed, involving two types of cocoa (Trinitario and Forastero) and three concentrations of Jackfruit extract (0%, 2.0%, and 4.0%), resulting in six treatments and 18 experimental units. Morphological evaluations of the fruit and physicochemical analyses of the cocoa beans (temperature, pH, °Brix) revealed that while Trinitario cocoa exhibited greater initial efficiency, the best treatment was Trinitario cocoa fermented in Rohan-type microfermentation boxes, in accordance with INEN 176 standards. Regarding sensory analysis, Trinitario cocoa fermented in Rohan boxes was the most favored. This research seeks to enhance cocoa fermentation and, consequently, improve the physical and sensory quality of chocolate bars.

EFFECT OF LITTER TYPE ON PRODUCTIVE PERFORMANCE, INCIDENCE OF FOOTPAD DERMATITIS, AND MORTALITY IN DE ENGORDE CHICKEN

Fri, 06 Jun 2025 00:00:00 +0000

The objective of this study was to compare three types of litter in broiler chicken rearing and to evaluate their effects on animal welfare and productivity. A total of 240 broiler chickens were randomly assigned to three treatments according to litter type: rice husk (T1), wood shavings (T2), and sand (T3). Each treatment included two replicates with 20 birds each. Evaluations were conducted across three production phases (starter, grower, and finisher) and during two seasons (dry and rainy). Productive performance parameters measured included feed intake, weight gain, feed conversion ratio, and carcass yield. Footpad lesions were assessed on three levels (none, mild, and severe). An economic analysis was also conducted through partial budget analysis. The results revealed significant differences (p < 0.05) in productive parameters and footpad lesion scores across litter types and seasons. Rice husk litter proved most effective in preventing severe lesions and maintaining a high percentage of lesion-free birds. The dry season yielded better weight gain results across all phases when compared to the rainy season. Economically, wood shavings were the most profitable, particularly during the dry season. In conclusion, regarding productivity and animal welfare indicators, both rice husk and wood shavings outperformed sand. These materials can be recommended when planning the establishment of broiler chicken flocks.

EFFECT OF TWO SEMEN CRYOPRESERVATION PROTOCOLS ON EQUINE ARTIFICIAL INSEMINATION OUTCOMES)

Carlos Fuentes. , Félix Contreras. , Pacífico Bonilla. , Alex Solís-Corrales. — Fri, 06 Jun 2025 00:00:00 +0000

The objective of this study was to evaluate the effect of two semen cryopreservation protocols on equine artificial insemination results. Treatment one (T1) used a centrifugation of 600 g for 11 minutes, while treatment two (T2) used a force of 750 g for eight minutes. Thirteen Quarter Horse mares, aged between four and eight years, were used. The body condition of the mares was approximately six to seven (on a scale of one to nine). Thirteen inseminations were performed with cryopreserved semen (T1: seven inseminations and T2: six inseminations with 750 g semen for eight minutes). The data were arranged in a contingency table. For the statistical analysis, the ChiSquare test was performed, using the IBM SPSS Statisctics version: 29.0.0.0 (241), where significant differences (P<0.05) were found for pregnancy rates when cryopreserved semen was used in T1 over T2 (T1: 71.40% and T2:

16.70%). It is concluded that T1 cryopreserved semen gave the best pregnancy rates using fixed-time artificial insemination.

Automeris metzli (LEPIDOPTERA: SATURNIIDAE) POTENTIAL PEST OF Artocarpus heterophyllus (ROSALES: MORACEAE)

Edgar. Araúz-Ábrego, Alonso. Santos-Murgas, Rubén D. Collantes-González — Fri, 06 Jun 2025 00:00:00 +0000

Jackfruit tree Artocarpus heterophyllus Lam. (Rosales: Moraceae), is a species native to Asia, whose fruits are consumed for their flavor and nutritional content, in addition to its wood being used in cabinetmaking and for the crafting of musical instruments. This plant is present in several Neotropical countries and about which there are reports of some species of pest insects; However, in raids carried out on a plot of approximately 7,500 m² in the process of adaptation for the agroecological production of fruit trees, located in Bagala, district of Boqueron, Chiriqui, Panama, the presence of many caterpillars provided with stinging spines (which can affect people's health) feeding on the foliage of A. heterophyllus was observed, so the aim of this work was to identify the said insect species and to determine if it is a pest of the crop. The study was conservationist, descriptive and exploratory in nature. The specimens were photographed in the field to observe in detail external morphological characters of the caterpillars (pigmentation and shape of the scoli, mainly) and specialized literature was consulted to confirm the identity of the insect. The results reflected that the stinging caterpillars correspond to Automeris metzli (Sallé, 1853) (Lepidoptera: Saturniidae), a polyphagous species with wide distribution in the province of Chiriquí and which affects other crops such as coconut and pigeon pea; However, this is a new report as a potential pest of A. heterophyllus.

CONTRIBUTIONS OF BIOREGULATORS IN CROP MANAGEMENT

Rolando Corella. , Dayane Littig. , Fernando Gálvez. , Enrique Sánchez-Galán. — Fri, 06 Jun 2025 00:00:00 +0000

Crop production requires technologies that enhance intrinsic processes of importance for productivity, or that represent solutions to problems in crop management, considering that adverse situations can affect the economic viability of the crop. The use of plant bioregulators (PGRs) is highly viable alternative, since they can promote, inhibit or modify the behavior of crops, benefiting important aspects such as growth, development, flowering, fruit set, quality, tolerance to stress factors, efficiency in the use of nutrients, fixed carbon, and water. PGRs have different effects, which depend on the type of crop, the ecophysiological behavior according to the phenological phase and the dose. The most important is the objective of use. The information presented here proposes access to information applied to the agronomic management of crops, as a reference for research, in the generation of new scientific knowledge and applied agricultural technologies. The most important is the objective of use.

HERBICIDE-RESISTANT WEEDS

Dustin Moreno-Serrano. — Fri, 06 Jun 2025 00:00:00 +0000

Since their introduction in the mid-1920s, herbicides have become a fundamental tool for weed control in modern agricultural production systems. However, the continued use of herbicides with the same site of action has promoted the development and proliferation of resistant weeds in crop fields. In recent years, efforts to understand resistance mechanisms at the molecular level have become a key component in preventing the evolution of resistance. Both target-site resistance (TSR) and nontarget-site resistance (NTSR) mechanisms have been identified as the most common herbicide resistance mechanisms. TSR is usually characterized by mutations that affect the herbicide's target protein, limiting its access to the site of action. Most of these mutations occur either in or near the catalytic domain. Furthermore, increased copy numbers of the gene encoding the target protein and also involved in TSR resistance mechanisms. On the other hand, NTSR encompasses a broad range of resistance mechanisms, such as herbicide-enhanced metabolism, reduced uptake, and translocation. NTSR mechanisms typically involve multiple gene families, including, but not limited to, cytochrome P450, glutathione S-transferases, and others. Both TSR and NTSR mechanisms can coexist in the same plant, resulting in an evolutionary process that leads to the ineffectiveness of one or more herbicides with different modes of action.