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Summary This experiment was conducted to assess a protocol combining 20% excess dietary methionine above the modern breeder pullet's requirement and AviPro MGF vaccine in controlling Mycoplasma gallispeticum (MG) infection. In a complete randomized design, a total of 276 6-wk-old breeder pullets, of the Ross 308 strain were allocated into 4 treatments, each with 3 floor pen replicates of 23 birds/pen: 1) nonvaccinated with adequate methionine (NVAM), 2) nonvaccinated with 20% excess methionine (NVEM), 3) Vaccinated with adequate methionine (VAM), 4) Vaccinated with 20% excess methionine (VEM). Vaccination with AviPro MGF at 6 wk of age was performed via drinking water. Results indicated that the rate of depictable growth and tracheal colonization of MGF vaccine strain is 6 wk postvaccination. Sera Elisa titers showed that an 8-wk-postvaccination period was required for the vaccine to stimulate the humoral immunity response against MG. The 20% excess methionine numerically increased the IgG titer against MG in comparison to other groups, yet this increase was not enough to generate protective titer count. Furthermore, the addition of 20% excess methionine above the recommended levels hindered the tracheal colonization rate and log10 values of AviPro MGF vaccine colony forming units from 5.9/mL of tracheal swab suspension in VAM group to 0.82/mL of tracheal swab suspension in VEM group (P ˂ 0.05). In conclusion, the 20% excess methionine above the modern requirements reduced the tracheal colonization of F-strain MG. Further research is needed to confirm the ability of excess dietary methionine to enhance the adaptive and acquired immunity of broiler breeder pullets.

The present study evaluated the effect of dietary protein levels on growth performance and blood parameters of juvenile marbled spinefoot (Siganus rivulatus). Five semipurified, isoenergetic (14.2 MJ digestible energy/kg; 84 g lipids/kg) diets were formulated to contain 30, 35, 40, 45, and 50 g crude protein (CP)/100 g diet. Groups of 15 juvenile fish (7.4 g individual weight) were randomly assigned in triplicate to each of the five treatments and offered the test diets three times daily ad libitum for 9 weeks. Total erythrocyte and differential leukocyte counts, hematocrit, hemoglobin, blood glucose, protein, and serum aspartate aminotransferase and alanine aminotransferase were evaluated. Survival was greater than 95% in all treatments. Maximum growth was observed in fish offered the diet containing 40 g CP/100 g diet crude protein. Differences in dietary protein level had no effect on the hepatosomatic and viscerosomatic indices of the fish, but whole body composition was influenced by diet. Blood para...

Improving water use efficiency in the agricultural sector, particularly in arid regions, is becoming increasingly important in response to increasing global population and concomitant demand for food, water, and land. The authors performed experiments to determine whether the use of super-absorbent polymers, also known as hydrogels, can increase plant survival, plant growth, and plant water use efficiency. The effect of hydrogel application proportions and application methods on plant survival and growth in clay and sandy clay loam (SCL) soils was investigated. Two pot experiments using Zea mays and Pinus pinea as model plants were performed. The hydrogel was applied at concentrations of 0, 1, 2, 3 and 4 g kg–1 soil in one of two methods: banding or mixing. Hydrogel effects on water retention in the two soil types were recorded. The results suggest that hydrogel banding at 0.4% application in SCL improves corn's fresh and dry above-ground biomass by 25%, and prolongs survival time of pine seedlings by 90%. Evapotranspiration was greater in soils banded with hydrogel at 0.4% and water use efficiency increased by 10–13% in both soils. Additionally, hydrogel increased water retention of SCL by up to 33% at 100 kPa, but had negligible effects when applied in clay soils. Accordingly, the efficacy of hydrogels in agriculture water conservation depends on using appropriate application methods and quantities.

Rowcover application has had variable effects on yield, depending on growing conditions. Strawberry (Fragaria × ananassa Duch) cvs. Chandler, Milcin, Milsei and Oso Grande response to rowcover was studied under a plasticulture-tunnel system on the Mediterranean coast of Beirut. Flowering and leaf number early in the season were comparable among covered and non-covered control groups. Rowcover reduced fruit yield and number in all cvs., primarily by the reduction in fruit number. Cultivars varied in yield, irrespective of the cover treatment and in yield distribution during the four months of harvest. The shading effect of rowcovers offset the effect of the slight rise in soil temperature (1-2°C) it caused. Soil chemical properties and NO3-N and P content in plant tissue were not affected by the treatments. Red spider mite (Tetrany-chus urticae Koch.) infestation started about two months after removal of rowcovers. There was no difference in the level of infestation due to treatments. We recommend...

Yield and mite infestation were studied in `Chandler', `Milcin', `Milsei', and `Oso Grande' strawberry, as affected by floating rowcover application (R) inside a greenhouse in Beirut. Results showed that R reduced yield of all cultivars in comparison to noncovered (C) plants, primarily by the reduction in fruit number (P ≤ 0.05), during the winter and spring harvests. Cultivars varied in yield, irrespective of the cover treatment (P ≤ 0.05) and in yield distribution over the 4 months of harvest (P ≤ 0.05). The shading effect of R offset the slight rise in soil temperature it caused. Air temperature did not drop to a level that would stop plant growth. Red spider mite infestation started after rowcover removal. Mite adult, larva, and egg populations were comparable between the R and C treatments (P > 0.05). Miticide sprays were the effective way to control mites. It is recommended from this study not to use rowcovers on greenhouse-grown strawberries in the Mediterranean region.