The present study was undertaken to determine the effects of varying light intensities on the morphology and physiology of the soft coral Pachyclavularia violacea. The soft corals P. violacea were treated by LED light and the illumination ranged from 50 to 200 £gmol photon m-2 s-1, i.e. high light (200 £gmol photon m-2 s-1), medium light (140 £gmol photon m-2 s-1), medium-low light (100 £gmol photon m-2 s-1 and low light (50 £gmol photon m-2 s-1). The theca length, the density of zooxanthellae and the concentrations of chlorophyll a and proteins were measured to evaluate the response of P. violacea to different light intensities. A significant longer theca length was found in the group of medium-low light (5¡V 9mm) than the groups of high and low light intensities (1-2mm) (p<0.001). And, the theca length in the groups of medium and medium-low was more close to their source population. Over the 6-month experimental periods, the densities of zooxanthellae in the groups of medium and medium-low were in the range of 1.5 ~3.8 x 105 (N/mg) which were significantly higher than other groups (p<0.01). The concentrations of chlorophyll a in the low light group were 0.5~ 2.0 (ng/mg) during the experimental periods which were significantly higher than other groups (p<0.05). In the fifth and sixth months, the concentrations of chlorophyll a per zooxanthellae in the group of medium-low were in the range of 0.4~5.8 Chl. a ¡Ñ 10-5 (ng/zoox.) which were significantly higher than other groups (p<0.01). The protein content in the group of low light was significantly lower than other groups in the fifth month. And, the protein contents were decreased significantly in all groups in the sixth month. Based on the results, it is concluded that theca length and the density of zooxanthellae were sensitive responses to light adaptation. The light intensity about 100 £gmol photon m-2 s-1 might be an appropriate range to culture the soft coral P. violacea because the theca length in the group was close to its source population.

Capture of CO2 by algae is an important mechanism for removal of this greenhouse gas from the atmosphere. For this reason, <i>Chlorella vulgaris</i> has beeen studied extensively over the years. A high growth rate of the microalgae is essential in order to increase the fixation rate of CO2 through photosynthesis. Though a number of studies have been carried out to optimize growth of <i>C. vulgaris</i>, high growth rates have not been achieved (Kleinheinz & Keffer, 2002).<p> In this study, a novel circulating loop photobioreactor with enhanced light distribution, gas mass transfer rate and mixing properties was used for the biokinetic study of <i>C. vulgaris</i>. The objective was to study individual effects of light intensity and CO2 concentration on the specific growth rate of <i>C. vulgaris</i>. Studies in this photobioreactor could generate high growth rates of 0.043 h-1. The effect of light intensity on the growth of the <i>C. vulgaris</i> was determined by varying intensity of light to the photobioreactor within a range of 26.945 mW to 431.128 mW, while the flow of air and CO2 were held constant. An increase in light intensity to the photobioreactor resulted in an increase in cell density and variation in the chlorophyll content of the <i>C. vulgaris</i> cells. Enhanced growth rates of <i>C. vulgaris</i> cells in this novel circulating loop photobioreactor could be attributed to the combined effect of the CO2 concentration and the uniform distribution of light throughout the reactor volume.<p> Interacting effects of dilution rate, light intensity and concentration of carbon dioxide on specific growth rate was studied in an externally illuminated, continuous flow stirred bioreactor. Steady flow of nutrient medium and air flow was maintained in the bioreactor. This study proved that the dilution rate has major significance at high concentrations of CO2 and high intensities of light. At high concentrations of CO2 at 10% (v/v) and 15% (v/v), increasing dilution rate from 0.005 h-1 to 0.01 h-1 could result in increasing growth rate by a factor of 1.45 and 2.16 respectively.

Two trials were conducted with the objective of investigating the effect of light intensity, approximately within the practical levels at confinement barns (1, 10, 20 and 40 lx), on production, processing characteristics and welfare of broilers raised to 35 d of age. In each trial, 950 Ross x Ross 308 chicks were placed randomly in each room with replication of individual light intensity treatment in two environmentally controlled experimental rooms. Within each large room, a small pen with 25 male and 25 female chicks was used for recording behaviour. Data were analyzed as a randomized complete block design, considering trial as a block. All chicks were exposed to 40 lx light intensity and 23 h light for the first 7 d, followed by treatment light intensity and 17 h day length thereafter. Body weight and feed consumption were determined at 7, 14, and 35 d of age. At the conclusion of each trial, 60 birds per treatment were processed to determine the detailed meat yield. For each replicate, behaviour was recorded for the 24 h period, starting at 16 or 17 d of age. At 23 d of age, serum samples were collected from three birds per room at the start, middle and end of light and dark periods, respectively, for melatonin estimation. Skeletal and foot pad, and ocular health were monitored at 31 and 32 d of age, respectively. Broiler live production (BW, FC, FCR and mortality) was unaffected by light intensity. Carcass, thigh and drum yield as a percentage of live weight decreased linearly with increasing light intensity. The 1 lx treatment resulted in heavier wings as a percentage of live weight. Birds exposed to 1 lx rested more and had reduced expression of foraging, preening, dust-bathing, stretching and wing-flapping behaviours in comparison to other light intensities, over the 24 h period and 17 h light phase. Light intensity did not affect circadian behavioural rhythms (24 h period) and behavioural patterns over the 17 h light phase. Diurnal rhythms of serum melatonin were also unaffected by light intensity with all treatments demonstrating a pronounced rhythm. Skeletal health was unaffected by light intensity but ulcerative foot pad lesions decreased linearly with increasing light intensity. Birds exposed to the 1 lx intensity had heavier and larger eyes. In conclusion, light intensity did not affect broiler production, behavioural and physiological rhythms and mortality but did affect carcass characteristics. Increased ulcerative foot pad lesions, ocular dimensions and altered behavioural expression at 1 lx light intensity are indicators of reduced broiler welfare.

Capture of CO2 by algae is an important mechanism for removal of this greenhouse gas from the atmosphere. For this reason, <i>Chlorella vulgaris</i> has beeen studied extensively over the years. A high growth rate of the microalgae is essential in order to increase the fixation rate of CO2 through photosynthesis. Though a number of studies have been carried out to optimize growth of <i>C. vulgaris</i>, high growth rates have not been achieved (Kleinheinz & Keffer, 2002).<p> In this study, a novel circulating loop photobioreactor with enhanced light distribution, gas mass transfer rate and mixing properties was used for the biokinetic study of <i>C. vulgaris</i>. The objective was to study individual effects of light intensity and CO2 concentration on the specific growth rate of <i>C. vulgaris</i>. Studies in this photobioreactor could generate high growth rates of 0.043 h-1. The effect of light intensity on the growth of the <i>C. vulgaris</i> was determined by varying intensity of light to the photobioreactor within a range of 26.945 mW to 431.128 mW, while the flow of air and CO2 were held constant. An increase in light intensity to the photobioreactor resulted in an increase in cell density and variation in the chlorophyll content of the <i>C. vulgaris</i> cells. Enhanced growth rates of <i>C. vulgaris</i> cells in this novel circulating loop photobioreactor could be attributed to the combined effect of the CO2 concentration and the uniform distribution of light throughout the reactor volume.<p> Interacting effects of dilution rate, light intensity and concentration of carbon dioxide on specific growth rate was studied in an externally illuminated, continuous flow stirred bioreactor. Steady flow of nutrient medium and air flow was maintained in the bioreactor. This study proved that the dilution rate has major significance at high concentrations of CO2 and high intensities of light. At high concentrations of CO2 at 10% (v/v) and 15% (v/v), increasing dilution rate from 0.005 h-1 to 0.01 h-1 could result in increasing growth rate by a factor of 1.45 and 2.16 respectively.

Two trials were conducted with the objective of investigating the effect of light intensity, approximately within the practical levels at confinement barns (1, 10, 20 and 40 lx), on production, processing characteristics and welfare of broilers raised to 35 d of age. In each trial, 950 Ross x Ross 308 chicks were placed randomly in each room with replication of individual light intensity treatment in two environmentally controlled experimental rooms. Within each large room, a small pen with 25 male and 25 female chicks was used for recording behaviour. Data were analyzed as a randomized complete block design, considering trial as a block. All chicks were exposed to 40 lx light intensity and 23 h light for the first 7 d, followed by treatment light intensity and 17 h day length thereafter. Body weight and feed consumption were determined at 7, 14, and 35 d of age. At the conclusion of each trial, 60 birds per treatment were processed to determine the detailed meat yield. For each replicate, behaviour was recorded for the 24 h period, starting at 16 or 17 d of age. At 23 d of age, serum samples were collected from three birds per room at the start, middle and end of light and dark periods, respectively, for melatonin estimation. Skeletal and foot pad, and ocular health were monitored at 31 and 32 d of age, respectively. Broiler live production (BW, FC, FCR and mortality) was unaffected by light intensity. Carcass, thigh and drum yield as a percentage of live weight decreased linearly with increasing light intensity. The 1 lx treatment resulted in heavier wings as a percentage of live weight. Birds exposed to 1 lx rested more and had reduced expression of foraging, preening, dust-bathing, stretching and wing-flapping behaviours in comparison to other light intensities, over the 24 h period and 17 h light phase. Light intensity did not affect circadian behavioural rhythms (24 h period) and behavioural patterns over the 17 h light phase. Diurnal rhythms of serum melatonin were also unaffected by light intensity with all treatments demonstrating a pronounced rhythm. Skeletal health was unaffected by light intensity but ulcerative foot pad lesions decreased linearly with increasing light intensity. Birds exposed to the 1 lx intensity had heavier and larger eyes. In conclusion, light intensity did not affect broiler production, behavioural and physiological rhythms and mortality but did affect carcass characteristics. Increased ulcerative foot pad lesions, ocular dimensions and altered behavioural expression at 1 lx light intensity are indicators of reduced broiler welfare.

Jellyfish blooms create problems worldwide, which may increase with global warming, water pollution, and over-fishing. Benthic polyps (scyphistomae) asexually produce buds and small jellyfish (ephyrae), and this process may determine the population size of the large, swimming scyphomedusae. Environmental factors that affect the asexual reproduction rates include food, temperature, salinity, and light. In the present study, polyps of Aurelia aurita (L.), originated from Tapong Bay, southwest Taiwan, were studied in different combinations of temperatures (T), light intensities (L), and salinities (S). In the T (20, 25, 30¢XC) ¡Ñ L (372, 56, and 0 lux) experiment which was with a 12 h light-12 h dark photoperiod, production of new buds decreased with warmer temperatures and stronger light intensity. Warm temperatures accelerated strobilation and increased the daily production of ephyrae. The proportion of ephyrae to total asexual reproduction (new buds + ephyrae) increased dramatically in warmer temperatures and stronger light. Survival period was reduced at the highest temperature. Strobilation did not occur at the lowest temperature in darkness. All measures of total asexual reproduction indicated that medium to high temperatures would lead to faster production of more jellyfish; however, continuous high temperatures might result in high polyp mortality. Light intensity affected asexual reproduction less than did temperature, only significantly accelerating the strobilation rate. Because the interactive effects of light and temperature were significant for polyp survival time and the production of jellyfish per polyp, combined light and temperature effects are likely important for strobilation in situ. In the T (27, 31, 35¢XC) ¡Ñ S (25, 30, and 35) experiment which was in dark environment, production of new buds decreased with higher temperatures and salinity. The proportion of ephyrae to total asexual reproduction (new buds + ephyrae) increased with warmer temperatures, but survival period was reduced at the highest salinity, and strobilation was substantially reduced, even though the temperature was warmer compared to the T ¡Ñ L experiment. Salinity affected asexual reproduction less than did temperature, only significantly affecting production of new buds, and slightly affecting survival period and the proportion of ephyrae to total asexual reproduction. According to these two experiments, warmer temperature may accelerate strobilation in light condition and lead to better yield of swimming jellyfish, however continuously warm temperature would reduce the yield by decreasing budding and higher mortality. Complete dark led to much less strobilation, especially at low temperatures, suggesting that the existence of light might be more important than light intensity. The effects of salinity on asexual reproduction were not as conspicuous as that of temperature and light.

Sixteen adult male and 8 adult female post moult mallards were equipped with radio transmitters, in a two year study (1977-6AHY-M and 4AHY-F; 1978-10AHY-M and 4AHY-F). Field-feeding was monitored at a lure crop and on adjacent grain fields. Ninety-two percent of the mallards radio-equipped were recorded at a field-feeding site at least once with 71% recorded field-feeding within one week. There was no significant difference in field-feeding activity between males and females. In the morning during periods of rain, mallards field-fed 0.55h longer, arriving 0.30h later and departing 0.9h later than mallards field-feeding during clear weather. The morning field-feeding period was longer in duration than the evening foeld-feeding period. Light intensity was the dominant climatological variable contributing to the arrival of mallards in the morning during periods of no rain (multiple R2=68.1%) and rain (R2=69.5%). Light appeared to act as an initiating cue for morning feeding activity. A high correlation existed between duration of stay during periods of no rain (r=0.815) and rain (r=0.860) suggesting that mallards remained longer at a field-feeding site in the morning by departing later, not arriving earlier. Light intensity was also the dominant climatological variable contributing to the arrival of mallards in the evening amongst those mallards which field-feed in both the morning and evening (R2=78.1%) and those which field-fed in the evening only (R2=63.3%). In addition, light intensity was the only contributing factor in the evening for all mallards departing a field-feeding site (R2=72.7%). Mallards were never recorded field-feeding longer than 15 minutes after there was non measurable light...

Sixteen adult male and 8 adult female post moult mallards were equipped with radio transmitters, in a two year study (1977-6AHY-M and 4AHY-F; 1978-10AHY-M and 4AHY-F). Field-feeding was monitored at a lure crop and on adjacent grain fields. Ninety-two percent of the mallards radio-equipped were recorded at a field-feeding site at least once with 71% recorded field-feeding within one week. There was no significant difference in field-feeding activity between males and females. In the morning during periods of rain, mallards field-fed 0.55h longer, arriving 0.30h later and departing 0.9h later than mallards field-feeding during clear weather. The morning field-feeding period was longer in duration than the evening foeld-feeding period. Light intensity was the dominant climatological variable contributing to the arrival of mallards in the morning during periods of no rain (multiple R2=68.1%) and rain (R2=69.5%). Light appeared to act as an initiating cue for morning feeding activity. A high correlation existed between duration of stay during periods of no rain (r=0.815) and rain (r=0.860) suggesting that mallards remained longer at a field-feeding site in the morning by departing later, not arriving earlier. Light intensity was also the dominant climatological variable contributing to the arrival of mallards in the evening amongst those mallards which field-feed in both the morning and evening (R2=78.1%) and those which field-fed in the evening only (R2=63.3%). In addition, light intensity was the only contributing factor in the evening for all mallards departing a field-feeding site (R2=72.7%). Mallards were never recorded field-feeding longer than 15 minutes after there was non measurable light...

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