Partitioning of photosynthates originating from bent shoots in the arching and high-rack culture systems of cut rose production

The arching and high-rack culture systems were developed and patented by Japanese rose growers. Both culture systems have bent canopies (lower bent shoots). In the arching culture system, shoots sprouting from the crown are harvested as cut flowers. However, the high-rack culture system also has a bent canopy originating from the mother stem (upper bent shoots) and flower stems sprout and is harvested at the top of each mother stem. Partitioning of photosynthates originating from bent shoots in arching and high-rack culture systems of rose production was investigated to elucidate how carbohydrates are re-allocated from the bent shoots in different culture systems of roses. At the flowering stage in both culture systems, 50–70% of ¹³C-photosynthates originated from bent shoots were exported to other parts within 72 h after ¹³CO₂ feeding to the bent shoot. In the arching culture system, photosynthates from lower bent shoots were partitioned mainly to the roots and crown. Similarly, in the high-rack culture system, between 71 and 86% of the exported carbon from the bent shoots were allocated to below the point of bending (roots + crown + mother stems) and only 9–28% was allocated to flowering shoots above the point of bending. In both culture systems, photosynthate translocation from the lower bent shoot directly to flowers was low. Accordingly, bent shoots in rose plants acted as a source of photosynthates, independent of culture system. The height of the bent shoots determined for a great deal in the re-allocation of the photosynthates, and provides a partial explanation for difference in production of cut roses.     

Hemolytic suppression roles of taurine in yellowtail Seriola quinqueradiata fed non-fishmeal diet based on soybean protein

ABSTRACT:   To elucidate the hemolytic suppression roles of taurine and the necessity of dietary taurine supplementation in yellowtail Seriola quinqueradiata fed a diet without fishmeal, juvenile fish with an initial body weight of 250 g were fed for 40 weeks in floating net cages on soybean protein diets supplemented with 0, 3.0, 4.5 and 6.0% taurine. Taurine concentration of the experimental diets were 0.03, 33.9, 52.8 and 71.6 mg/g, respectively. On the 21st week, fish fed the taurine unsupplemented diet had inferior growth and feed performances, higher death, and there were incidences of green liver and hemolytic anemia. In this group, hepatic and plasma taurine concentrations, serum osmolality and osmotic tolerance of erythrocytes (EC50 value) were significantly lower, and plasma hydroperoxide concentration was markedly higher than in the taurine supplemented groups. These conditions markedly improved corresponding with the increase of dietary taurine concentration. These results indicate that taurine plays a role in hemolytic suppression through osmoregulation and biomembrane stabilization in fish. In addition, it is suggested that yellowtail requires dietary taurine as an essential nutrition for maintaining physiological condition normally.     

The relationship between reduced glutathione level and glutathione S-transferase activity in sheep erythrocytes.

The relationship between reduced glutathione (GSH) level and glutathione S-transferase (GST) activity in erythrocytes was examined, using sheep erythrocytes, which have varying GSH concentrations, and dog erythrocytes with an inherited high concentration of GSH. There was a positive correlation (r = 0.529, p < 0.001) between the GSH level and GST activity in sheep erythrocytes. In dog erythrocytes, the GST activity in high-GSH cells was significantly (p < 0.001) higher than that in normal-GSH cells. These results indicate that the activity of GST in erythrocytes is directly correlated with the intracellular GSH level.     

Ultrastructure of parathyroid glands of growing chickens with vitamin D deficiency rickets

Ultrastructural studies were conducted on the parathyroid glands (PTG) of 2- to 7-week-old nontreated control growing broiler chickens (group A, 6 chickens); the same aged chickens with experimentally induced vitamin D deficiency rickets (18 morbid chickens each from groups B, C, and D); and in 4- to 9-week-old chickens naturally affected with rickets (group E, 8 chickens). Four types of principal cells were classified in the PTG of clinically normal birds and in PTG of birds with secondary hyperparathyroidism as follows: Type I cell (small cell in the resting phase); type II cell (medium-sized cell with well-developed rough-surfaced endoplasmic reticulum in the synthesizing phase); type III cell (large cell with well-developed Golgi apparatus and cytoplasmic organelles in the packaging and secretory phase); and type IV cell (medium-sized cell with poor cytoplasmic organelles in the involuting phase). Many coated vesicles were observed in type II and type III cells. In young control chickens, principal cells of the PTG were considered in the resting phase; in older control chickens, there were increased numbers of cells in the synthesizing phase. In the vitamin D deficiency groups, principal cells were in the synthesizing and packaging and secretory phases. In birds with naturally occurring rickets, principal cells were in packaging and secretory phases, with a small number of cells in the involuting phase. The ultrastructural changes of the PTG from the initial to final phases in growing chickens with secondary hyperparathyroidism were demonstrated.     

Epizootiological and virological studies of foal diarrhea associated with serotype 3 rotavirus

Epizootiological and virological studies were conducted on foal diarrhea occurring in 3 foal-raising locations in a light horse farm from March to July, 1987. At the first location, although 27 (75%) of 36 foals had developed diarrhea, the isolation rate of rotavirus (RV) was low (5/14 feces, 36%). Many of the foals had the disease as early as 23 days after birth. At the second and third locations, 21 (27%) of 78 foals and 41 (76%) of 54 foals were affected with diarrhea. Isolation rates of RV were 90% (20/22 feces) and 100% (26/26 feces), respectively. The diseased cases were observed throughout the short period from June to early July and on foals aged from 63 to 65 days. These findings suggested the importance of RV as a causal agent of foal diarrhea at the latter location, RV and/or other agents at the former location. All the 3 strains of RV represented from each location were identified as serotype 3 by plaque reduction neutralization test against the antiserums of serotypes 1 to 6 of RV. However, the 3 strains showed low cross-reactivity with antiserum of the serotype 3 of the equine RV.     

Isolation of Chuzan virus, a new member of the Palyam subgroup of the genus Orbivirus, from cattle and Culicoides oxystoma in Japan

Five virus strains with identical antigenic properties were isolated from 3 RBC suspensions obtained from 2 healthy sentinel calves and from 2 pools of Culicoides oxystoma in cultures of a hamster lung cell line (HmLu-1). The virus was tentatively named Chuzan virus. The Chuzan virus was classified as a new member of the Palyam subgroup of the genus Orbivirus on the basis of its physicochemical, morphologic, and antigenic properties.