Previous reports have suggested that green light enhances broiler growth at an early age, whereas blue light enhances growth at older ages. The aim of this study was to examine the effect of a switch in monochromatic light at 2 ages on growth and development of broilers. Male chicks (Anak, n = 640) were used. After hatch, chicks were weighed, wing-banded, and blocked into treatment groups. Chicks were grown in 1-m2 pens in 8 isolated light-proof rooms (20 birds/pen). The light treatments were (1) Control white (mini-incandescent lamps), 2) blue light-emitting diode (LED) lamps, 3) green LED lamps, 4) blue LED switching to green at 10 d of age, 5) blue LED switching to green at 20 d of age, 6) green LED switching to blue at 10 d of age, and 7) green LED switching to blue at 20 d of age. There were 8 pens for treatment 1, and 4 pens for each of the other treatments. The light schedule was 23L:1D, and intensity was 0.1 watts/m2. BW and feed consumption were recorded. Green light birds were significantly heavier at 4 d of age. Switching light at 10 d of age from green to blue caused a further increase in BW. This improved growth was maintained until the end of the experiment. Light switching from blue to green at 20 d of age also improved growth as compared with white light. Average feed efficiency and mortality rate did not differ between groups. No association was observed among light treatment, performance, and plasma triiodothyronine concentration. We suggest that green light stimulated growth of birds at early age, and shifting birds to a different light environment at 10 or 20 d of age might further stimulate growth.
A high-density, ordered array containing thousands of microwells is fabricated on an optical imaging fiber. Each individually addressable microwell is used to accommodate a single living cell. A charged coupled device (CCD) detector is employed to monitor and spatially resolve the fluorescence signals obtained from each individual cell, allowing simultaneous monitoring of cellular responses of all the cells in the array using reporter genes (lacZ, EGFP, ECFP, DsRed) or fluorescent indicators. Yeast and bacteria cell arrays were fabricated and used to perform multiplexed cell assays with resolution at the single-cell level. Monitoring gene expression in single yeast cells carrying a two-hybrid system was used to detect in vivo protein-protein interactions. The single-cell array technology provides a new platform for monitoring the unique multiple responses of large populations of individual cells from different strains or cell lines. The rich data acquired by the cell array has the potential to be employed as a new tool for cell biology research as well as to improve cell-based high-throughput screening (HTS) applications, such as the validation of new disease-associated cellular targets and the early-stage evaluation of potential drug candidates.
Water availability and cost is a limiting factor in the growth of turfgrass under warm semi‐arid zone conditions. Methods of reducing water consumption of turfgrasses in these zones are of major importance. Water consumption and dry matter yield of clippings were determined for 11 turfgrass species or cultivars, 2 of which were cool season and 9 warm‐season types. The former belong to the C‐3 and the latter to the C‐4 group. The plants were grown in containers under typical summer conditions of the warm, semi‐arid zone. The growth rate of plants in the C‐3 groups was similar to that of those in the C4 group but their water consumption was higher. Amongst the C‐4 group, those plants with a sparse, vertical, growth habit, typical of forage crops, had a higher growth rate and water consumption than the dense, low growing ones. A significant correlation coefficient (r = 0.71 at p<0.05), was found between water consump tion and growth rate for the C‐4 plants. Delaying irrigation until the onset of temporary wilting, caused a significant decrease in water consumption and growth (up to 35%) in most gasses. Raising the clipping height from 3 cm to 6 cm for a period of 6 weeks led to increased vigor in all grasses as evidenced by growth rate, chlorophyll content and water consumption. This effect was continuous throughout the measurement period for the C‐3 types, but was temporary for the C‐4 types, declining again after 6 weeks. In experiments carried out under constant 34.5 C temperature, net photosynthesis of tall fescue (Festuca arundinacea Schreb. ‘Alta’) (C‐3) was only about one‐third that of C4 grasses although the evapotranspiration rate was equally high. The water uptake of the C4 type Zoysia matrella (L.) Merr. ceased at a much higher soil water potential than that observed for the C‐3 tall fescue and other C‐4 types. The decline of the rate of photosynthesis preceded the decrease in transpiration rate caused by the decreasing soil water potential. The most important single factor affecting water use was the carbon fixation pathway to which the grasses belonged. Whilst the choice of a species or cultivar of turfgrass is generally made on the basis of temperature adaptation, should the criterion be water consumption in relation to availability and cost, then C‐3 varieties should not be chosen for warm semi‐arid zones to the extent that is practiced now.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.