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1.
Three experiments were conducted to investigate the growth, survival, and standardized cohort biomass of Pacific bluefin tuna, Thunnus orientalis, larvae fed nutritionally enhanced prey during the first week of feeding using two commonly used, commercially available enrichment media, AlgaMac Enrich and Marine Glos. T. orientalis larvae exhibited exponential growth in standard length and dry weight. The daily specific growth rates in length and weight are the first reported for T. orientalis larvae and the averages ranged from 3.8 to 4.1% and 27.5%, respectively, for larvae in the AlgaMac treatment and from 4.1 to 6.1% and 31.5%, respectively, in the Marine Glos treatment. Average daily growth rates in length ranged from 0.16 to 0.23 mm/d for larvae in the AlgaMac treatment and from 0.17 to 0.27 mm/d for those in the Marine Glos treatment. Daily growth rates in length were similar to those reported for other tuna larvae reared in the laboratory but slower than most published estimates for larval tunas in situ at similar water temperatures. Mean prey number per gut was positively associated with mean prey level in the tank. Both enrichment media appear to be good sources of nutritional improvement of planktonic prey for T. orientalis larvae.  相似文献   
2.
In the aquaculture of the Japanese flounder Paralichthys olivaceus, hypermelanosis, a malpigmentation condition in which the scales of a significant area on the blind side express the characteristics of those on the ocular side, remains a major concern. Since introducing sand into the rearing tank effectively suppresses hypermelanosis, the inhibitory effects of various characteristics of the surface of the tank floor were investigated. Although an inhibitory effect was observed in both tanks with a sand-image floor and a sand-pasted floor, the strongest effect was found in tanks with a dimpled floor. In addition, covering the inner surface of the tank with net also inhibited hypermelanosis. Using a commercially available corrugated plate, the inhibition of hypermelanosis was confirmed with a noted increase in this effect when combined with light coloration. Juveniles tended to situate themselves in the valley portions of the corrugated plate, suggesting that floor contact with the blind side may contribute to hypermelanosis inhibition. Further observations on the floor contact area with various floor configurations suggested that hypermelanosis is locally suppressed in the areas with floor contact. Therefore, suppression by an undulated (both dimpled and corrugated) floor is likely due to an increase in floor contact area with the blind side.  相似文献   
3.
4.
Sweet peppers (cv. Tosajishi beauty) with leaf blight symptoms were observed in Kochi Prefecture, 2003. Initially, small spots formed on leaves, and later enlarged to brown to dark brown spots, and eventually blighted leaves fell. Several bacteria that caused the same symptoms were isolated and subsequently reisolated. These bacteria were identified as Pseudomonas cichorii on the basis of bacterial characteristics and the 16S rRNA gene sequence. This is the first report of bacterial leaf blight in the sweet pepper in the world.  相似文献   
5.
To investigate the reason for the high mortality of cultured juvenile Pacific bluefin tuna (PBT), especially during land‐based culture, we examined the effect of the rate of light‐intensity change during the dawn period. Juvenile PBT kept in a natural light environment (control) were compared with those exposed to an artificially slowed change in light intensity during the dawn period (test group). For the test group, lamps, which were connected to automatic timers and placed above the rearing tank, were switched on from 0345 to 0515 h at 15‐min intervals. After 9 d, the survival rate of the test and control group was identical. Between Day 1 and Day 6, whole‐body cortisol levels were not different between groups. However, whole‐body glucose levels in the test group were significantly higher than those in the control group. Both groups displayed a diel rhythm in plasma cortisol concentration that peaked at 0300–0600 h. These results suggest that slowing the increase in light intensity during the dawn period did not improve survival and that low light intensity itself induces high mortality in cultured PBT juveniles.  相似文献   
6.
We previously reported that the progression of staining-type hypermelanosis spontaneously ceased at a specific time and area in Japanese flounder Paralichthys olivaceus. To examine whether time is a limiting factor in the spontaneous cessation of staining, we experimentally controlled the initiation and duration of staining by manipulating the bottom substrate condition in the fish tanks. At 151 days post hatching (DPH; 11 weeks), spontaneous cessation of staining was observed in fish reared in tanks without a sandy substrate. However, staining resumed (or was initiated) in tanks where sand was removed from 11 weeks, indicating a strong but temporary effect of bottom sand and the absence of time limitation in the staining progression by 151 DPH. Extended duration of the inhibitory period of hypermelanosis expansion (9 weeks or more) aided in only a 20 % reduction of the final staining area because of the increased rate of staining expansion. The bottom sandy substrate decreased the visibility of the staining area in individuals, but this was observed only before the completion of the staining expansion. These findings are discussed in relation to possible presence of area limitation of future staining, as well as the fundamental nature of staining.  相似文献   
7.
It is empirically known that wood can cause a comfort enhancement effect in humans. On the other hand, not enough scientific knowledge based on evidence-based research is available on this subject. However, data using physiological indices have increasingly accumulated in recent years. This review provides an overview of the current situation for peer-reviewed reports related to the physiological effects of wood. We reviewed reports that elucidated the effects of wood-derived stimulations on the olfactory, visual, auditory, and tactile sensations using physiological indices such as brain activity (e.g., near-infrared spectroscopy) and autonomic nervous activity (e.g., heart rate variability and blood pressure). It became clear that many studies were limited by (1) a small number of participants, mostly aged in their 20s; (2) use of only a single stimulus (e.g., only olfactory or only visual), or (3) an incomplete experimental design. In addition, this review examined the field of forest therapy, for which there is abundant research. Further study is needed to elucidate the physiological effects of wood on humans.  相似文献   
8.
The numbers of tumor infiltrating T lymphocytes, B lymphocytes and antigen presenting cells were evaluated in an immunohistochemical manner in 140 canine spontaneous mammary gland tumor (MGT) tissues. As a result, we found a statistically significant increase in the number of intratumoral T lymphocytes (23.2 ± 23.8) in the malignant MGT group (n=51) compared with the benign MGT group (14.0 ± 16.0, n=89; P<0.05). Moreover, the high T lymphocyte infiltration in the malignant group correlated with poor prognosis in multivariate analysis (P<0.05). This study indicated the relationship between increased infiltrating T lymphocytes and canine MGT malignancy.  相似文献   
9.
The effects of fasting on the quality of the dorsal and ventral ordinary muscles from cultured Pacific bluefin tuna (Thunnus orientalis) during chilled storage were investigated. Tuna were subjected to fasting for 2 days in the summer or 6 days in the winter prior to harvesting. The breaking strength of the dorsal ordinary muscle sampled in the summer increased until 24 h and then decreased. There were no significant differences in the lipid and glycogen content of the ordinary muscle after 9 h of storage between the controls and either fasting group. The pH of the ordinary muscle subjected to summer and winter fasting was higher than in the controls after 24–48 h of storage. However, the relationship between the pH and glycogen content was unclear. The metmyoglobin content during chilled storage was lower in the ordinary muscles from either fasting group than in the controls. In conclusion, fasting for 6 days in the winter improved the color stability of the ordinary muscle without a decline in its lipid content.  相似文献   
10.
ABSTRACT

Sugarcane smut, caused by Sporisorium scitamineum, is one of the most important sugarcane diseases in Japan. Wild sugarcane, Saccharum spontaneum, is known to be a key breeding material to obtain high-yielding clones. In this study, we sought to identify Japanese wild sugarcane accessions with high resistance to smut. Thirty wild sugarcanes and three sugarcane cultivars were tested by the pinprick method. The results of the inoculation tests aided in identifying wild sugarcanes with high resistance to smut disease, namely JW90, Iriomote8, and Iriomote15. After screening the germplasm, progeny distribution of smut resistance from the inoculation test and dry matter productivity in the smut disease-free field were compared. The highly resistant wild sugarcane accession had a much better impact on progeny distribution of smut resistance compared with the susceptible accession. No relationship was found between smut resistance and dry matter productivity in both populations.  相似文献   
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