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The use of conventional pesticides becomes a complicated issue as more species of insect pests become resistant to them. Nanopesticides suit new approaches in pest control. Herein, we tested the toxicological efficacy of imidacloprid compared with three of its nanoformulations (IMD01, IMD02, and IMD03) on second and fourth instar of Culex pipiens larvae. Furthermore, we assessed the synergistic actions of piperonyl butoxide (PBO) on imidacloprid and its nanoformulations against second and fourth instar of C. pipiens. The nanoformulation (IMD03) was the most potent insecticide (LC50 = 14, 6, and 2 ng/mL after 24, 48, and 72 h of exposure, respectively), whereas the lowest toxic nanoformulation was IMD01. However, imidacloprid had the lowest toxicity among the tested compounds (LC50 = 1015, 705, and 621 ng/mL after 24, 48, and 72 h of exposure, respectively). PBO significantly synergized imidacloprid and its nanoformulations. However, the most synergistic effects were on IMD03 and the lowest was imidacloprid itself. Based on our results, nanopesticides are currently the most promising tool to control C. pipiens mosquitoes. However, further semifield and field studies should be done to illustrate the efficacy of imidacloprid and its nanoformulations on C. pipiens mosquitoes.

The use of conventional pesticides becomes a complicated issue as more species of insect pests become resistant to them. Nanopesticides suit new approaches in pest control. Herein, we tested the toxicological efficacy of imidacloprid compared with three of its nanoformulations (IMD01, IMD02, and IMD03) on second and fourth instar of Culex pipiens larvae. Furthermore, we assessed the synergistic actions of piperonyl butoxide (PBO) on imidacloprid and its nanoformulations against second and fourth instar of C. pipiens. The nanoformulation (IMD03) was the most potent insecticide (LC50 = 14, 6, and 2 ng/mL after 24, 48, and 72 h of exposure, respectively), whereas the lowest toxic nanoformulation was IMD01. However, imidacloprid had the lowest toxicity among the tested compounds (LC50 = 1015, 705, and 621 ng/mL after 24, 48, and 72 h of exposure, respectively). PBO significantly synergized imidacloprid and its nanoformulations. However, the most synergistic effects were on IMD03 and the lowest was imidacloprid itself. Based on our results, nanopesticides are currently the most promising tool to control C. pipiens mosquitoes. However, further semifield and field studies should be done to illustrate the efficacy of imidacloprid and its nanoformulations on C. pipiens mosquitoes.

Intensive silvopastoral system (ISS) is a successful sustainable grazing system for dual-purpose cattle with growing adoption in the tropics; however, there is a concern on the quality of dairy products from this system. The aim of this study was to compare the ISS with the traditional monoculture system (MS) in terms of milk composition, soft cheese composition and yield, and the sensory acceptability of cheese during two seasons of a tropical area in Mexico. Twenty-four cows at the first 3 months postpartum were allocated evenly to two groups. The cows in ISS grazed in paddocks of Leucaena leucocephala associated with Cynodon nlemfuensis whereas the cows in MS grazed in C. nlemfuensis. Milk samples were collected weekly during the rainy and dry seasons for chemical analysis and fresh soft cheese making. The cheese was analyzed chemically, and cheese acceptability was evaluated for the sensory attributes of appearance, texture, flavor, color, and overall acceptability. Milk percentages of fat, protein, SNF, and lactose did not differ significantly between systems being, 3.5, 3.0, 8.1, and 4.4 in ISS and 3.6, 2.9, 8.0, and 4.4 in MS, respectively. Similar results were obtained for cheese content of fat/DM and protein/DM. In the rainy season, adjusted cheese yield from ISS (24.2%) was higher compared with MS (20.8%). Cheese texture in the dry season showed more acceptability for ISS. This study provide absence of adverse effect of ISS on milk and cheese composition; moreover, ISS improve the yield and acceptability of soft cheese.

Yield, chemical composition, fatty acid profile, and sensory acceptability of Panela cheese produced from cows grazing in an intensive silvopastoral system (ISS) with Leucaena leucocephala and Cynodon nlemfuensis were evaluated and compared with Panela cheese from cows grazing a monoculture system (MS) of C. nlemfuensis only. The experiment lasted for 9 weeks in a tropical area in Mexico using ten crossbred cows (30–90 days of milking) assigned homogenously as five cows in each experimental group. No significant differences were found between the two systems for milk and cheese gross composition. Panela cheese from ISS showed lower content of the hypercholesterolemic fatty acids, accompanied with higher content of omega-3, omega-6 and polyunsaturated fatty acids. In addition, Panela cheese from ISS showed higher preference for the attributes of appearance, texture, flavor, and overall acceptability. It is concluded that Panela cheese from cows grazing in ISS has better acceptability and nutritional properties than that produced from MS with grass only.

Intensive silvopastoral systems are being increasingly disseminated in the tropical areas of Mexico, Central and South America, so it is important to know the quality of the animal products generated in these systems. Fatty acid profile of fresh soft cheese (Domiati type) produced from milk of cows grazing Leucaena leucocephala associated with Cynodon nlemfuensis in an intensive silvopastoral system (ISS) was evaluated and compared with a cheese produced from cows grazing a traditional monoculture system (MS) of C. nlemfuensis. The legume L. leucocephala contains phenolic compounds that could affect the fatty acid biohydrogenation in the rumen and therefore the fatty acid profile of resultant milk and cheese. Milk samples from cows in both diets (systems) were processed monthly for cheese making and cheese samples were analyzed for fatty acid profile. The experimental period lasted for 10 months covering the rainy and dry season of a tropical area in Mexico. The results showed that the cheese produced in ISS had significantly lower content (P0.05) of the saturated fatty acids lauric, myristic and palmitic and significantly higher content (P0.05) of stearic, linoleic and γ-linolenic acids. Additionally, higher content (P0.05) of the polyunsaturated fatty acids and omega-6 fatty acids were found in the cheese from ISS. The results suggest that fresh soft cheese produced from silvopastoral systems based on L. leucocephala has a better fatty acid profile than that produced from the traditional MS with grass only.