The Effects of Reduced Salinity on the Shell Growth of Small Mytilus Edulis

1984 ◽  
Vol 64 (1) ◽  
pp. 171-182 ◽  
Author(s):  
Patricia C. Almada-Villela
Keyword(s):  
Growth Rate ◽  
Mytilus Edulis ◽  
High Salinity ◽  
Shell Growth ◽  
Experimental Period ◽  
Gradual Decline ◽  
Poor Growth ◽  
Term Response ◽  
Better Than

The shell growth of small coastal Mytilus edulis L. was measured at three different constant low salinities over short periods of time. Growth was significantly depressed in 6·4 and 16‰ S but not in 22·4‰ S. Fluctuating salinities between 0 and 32‰ S depressed growth whether the fluctuations were of sinusoidal or abrupt form. After 1 week of preconditioning to constant 32‰ S the growth of coastal (Bangor) mussels was better than estuarine (Conwy) mussels. However, after two weeks’ preconditioning to 32‰ S the estuarine mussels displayed the best growth. In the fluctuating regime, both coastal and estuarine mussels exhibited poor growth rates. The long-term response of the shell growth of coastal M. edulis was followed over a period of 44 days. Salinities in the range 1·8–9·6‰ S were lethal to the mussels within 10 days. In 12·8 and 16‰ S growth was initially delayed but recovered eventually. There was a gradual decline in the growth rate of the mussels exposed to the higher salinities (19·2–32‰) and an improvement in the growth of the mussels living in lower salinities (12·8 and 16‰) to levels nearly matching that of the high salinity animals by day 37. This suggests that acclimation of the shell growth of M. edulis to salinities in the 12·8–28·8‰ S range was achieved by the mussels during the experimental period.

The effects of lactation length and feed level on subsequent reproductive performance in the sow

1984 ◽  
Vol 1984 ◽  
pp. 28-28
Author(s):  
R. W. Henry ◽  
D. W. Pickard ◽  
P. E. Hughes
Keyword(s):  
Reproductive Performance ◽  
Post Partum ◽  
Experimental Period ◽  
List Type ◽  
Large White ◽  
Lactation Length ◽  
Creep Feed ◽  
Subsequent Birth ◽  
Term Response

Previous research suggests that the feeding stratagem employed during a particular stage of the reproductive cycle may evoke an immediate response and/or a more long-term response in reproductive performance. This trial was designed to investigate the effect of feed restriction during lactation on reproductive performance when lactation periods of 10 and 35 days were employed.Eighty, second to fifth parity Large White x Landrace sows were used in the experiment. The sows were allocated on a parity and liveweight basis to one of the following four lactation treatments:-1)35 day lactation; fed 7 kg/day of a standard proprietary diet during lactation2)35 day lactation; fed 3 kg/day during lactation3)10 day lactation; fed 7 kg/day during lactation4)or 10 day lactation; fed 3 kg/day during lactation.All sows were then fed 3 kg/day during the weaning to remating interval and 2.2 kg/day throughout gestation. Creep feed was offered ad libitum to the litters of sows on treatments 1 and 2 from 10 days post partum. Liveweight and backfat (maximum shoulder, P2 and minimum loin) measurements were taken at regular intervals throughout the experimental period. Piglet weaning weights and subsequent birth weights were recorded.

scholarly journals Prevalent pH Controls the Capacity of Galdieria maxima to Use Ammonia and Nitrate as a Nitrogen Source

Plants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 232
Author(s):  
Manuela Iovinella ◽  
Dora Allegra Carbone ◽  
Diana Cioppa ◽  
Seth J. Davis ◽  
Michele Innangi ◽  
...  
Keyword(s):  
Growth Rate ◽  
Nitrogen Source ◽  
Culture Media ◽  
Nitrogen Sources ◽  
Photochemical Activity ◽  
Good Growth ◽  
Medium Ph ◽  
Photochemical Process ◽  
Term Response

Galdieria maxima is a polyextremophilic alga capable of diverse metabolic processes. Ammonia is widely used in culture media typical of laboratory growth. Recent reports that this species can grow on wastes promote the concept that G. maxima might have biotechnological utility. Accordingly, there is a need to know the range of pH levels that can support G. maxima growth in a given nitrogen source. Here, we examined the combined effect of pH and nitrate/ammonium source on the growth and long-term response of the photochemical process to a pH gradient in different G. maxima strains. All were able to use differing nitrogen sources, despite both the growth rate and photochemical activity were significantly affected by the combination with the pH. All strains acidified the NH4+-medium (pH < 3) except G. maxima IPPAS P507. Under nitrate at pH ≥ 6.5, no strain was able to acidify the medium; noteworthy, G. maxima ACUF551 showed a good growth performance under nitrate at pH 5, despite the alkalization of the medium.

Growth of Lampsilis radiata (Bivalvia: Unionidae) in Sand and Mud: A Reciprocal Transplant Experiment

1986 ◽  
Vol 43 (3) ◽  
pp. 548-552 ◽  
Author(s):  
Scott G. Hinch ◽  
Robert C. Bailey ◽  
Roger H. Green
Keyword(s):  
Growth Rate ◽  
Shape Change ◽  
Unit Length ◽  
Shell Growth ◽  
Shell Shape ◽  
Transplant Experiment ◽  
Reciprocal Transplant Experiment ◽  
Rate Analysis ◽  
Two Populations

To examine the effects of habitat on shell growth and form, freshwater unionid clams (Lampsilis radiata) were reciprocally transplanted between a sandy and a muddy site in Inner Long Point Bay, Lake Erie. There were significant differences in the initial shell dimensions of the two populations, with the sand clams being larger and less obese than the mud clams. Pretransplant growth rate analysis, using annual rings, showed that long-term growth in the sand was greater than that in the mud. After 16 wk the transplanted clams were recovered. Overall growth rate was affected by the source of the clams, while transplant destination affected shape change (height growth per unit length growth). This suggests that shell growth rates may be under direct genetic control, while shell shape can be adaptively modified by environmental cues.

Effect of soaking the meal ration of growing pigs in water or skim milk

1962 ◽  
Vol 4 (3) ◽  
pp. 313-318 ◽  
Author(s):  
R. S. Barber ◽  
R. Braude ◽  
K. G. Mitchell
Keyword(s):  
Growth Rate ◽  
Skim Milk ◽  
Experimental Period ◽  
Growth Efficiency ◽  
Growing Pigs ◽  
Backfat Thickness ◽  
Food Utilisation ◽  
Dressing Percentage ◽  
The Difference ◽  
Better Than

1. Thirty-two individually-fed pigs were used to determine the effects of soaking their daily meal ration in either water or in liquid skim milk and water for approximately 24 hr. before feeding. The experimental period continued from about 10 weeks of age to bacon weight.2. Neither soaking procedure had any significant effect on the rate of growth, efficiency of food utilisation, dressing percentage, carcass length, backfat thickness or commercial grading results of the pigs.3. The growth rate and efficiency of food utilisation of the pigs given meal plus skim milk were significantly better than for those given the all meal diet. The dressing percentage of the former was also significantly higher than the latter, but there were no significant differences between the two groups in carcass length or backfat thickness.4. Possible reasons for the difference in performance of the all meal and meal plus skim milk-fed pigs are discussed.

scholarly journals Comparison of an antioxidant system in tolerant and susceptible wheat seedlings in response to salt stress

2018 ◽  
Vol 15 (4) ◽  
pp. e0805 ◽  
Author(s):  
Kaouthar Feki ◽  
Sana Tounsi ◽  
Faiçal Brini
Keyword(s):  
High Salinity ◽  
Nacl Stress ◽  
Salt Tolerant ◽  
Short Term ◽  
Antioxidant Defence ◽  
Wheat Seedlings ◽  
Antioxidant Defence System ◽  
Short And Long Term ◽  
Term Response

It has been demonstrated previously that the physiological and molecular analysis of seedlings of the tolerant (Om Rabia3) and susceptible (Mahmoudi) Tunisian wheat genotypes were different at short and long-term response to salinity. In this study, we examined the antioxidant defence system in seedlings of these two cultivars at short-term response to different NaCl concentrations. The findings showed that high salinity tolerance of cv. Om Rabia3, as manifested by lower decrease in its dry biomass, was associated with lower malondialdehyde and hydrogen peroxide contents, lower accumulation of the superoxide (O2⎯) in the roots and the shoots, and also lower decrease in ascorbate content than those in cv. Mahmoudi. Moreover, the expression of some genes coding for antioxidant enzymes such as the catalase, the superoxide dismutase and the peroxidase were enhanced by NaCl stress especially in the salt-tolerant cultivar. In parallel, their activities were  increased in response to the same condition of stress and especially in the cv. Om Rabia3. Taken together, these data suggested that the capacity to limit oxidative damage is important for NaCl tolerance of durum wheat.

scholarly journals Growth acceleration results in faster telomere shortening later in life

2021 ◽  
Vol 288 (1956) ◽  
pp. 20211118
Author(s):  
Pablo Salmón ◽  
Caroline Millet ◽  
Colin Selman ◽  
Pat Monaghan
Keyword(s):  
Growth Rate ◽  
Blood Cells ◽  
Later Life ◽  
Experimental Period ◽  
Growth Trajectory ◽  
Telomere Shortening ◽  
Time Period ◽  
Accelerated Growth ◽  
Telomere Dynamics

There is a wealth of evidence for a lifespan penalty when environmental conditions influence an individual's growth trajectory, such that growth rate is accelerated to attain a target size within a limited time period. Given this empirically demonstrated relationship between accelerated growth and lifespan, and the links between lifespan and telomere dynamics, increased telomere loss could underpin this growth–lifespan trade. We experimentally modified the growth trajectory of nestling zebra finches ( Taeniopygia guttata ), inducing a group of nestlings to accelerate their growth between 7 and 15 days of age, the main phase of body growth. We then sequentially measured their telomere length in red blood cells at various time points from 7 days to full adulthood (120 days). Accelerated growth between 7 and 15 days was not associated with a detectable increase in telomere shortening during this period compared with controls. However, only in the treatment group induced to show growth acceleration was the rate of growth during the experimental period positively related to the amount of telomere shortening between 15 and 120 days. Our findings provide evidence of a long-term influence of growth rate on later-life telomere shortening, but only when individuals have accelerated growth in response to environmental circumstances.

Effect of Shading on Activity of Imazamethabenz and Fenoxaprop in Wild Oat (Avena fatua)

Weed Science ◽  
1994 ◽  
Vol 42 (1) ◽  
pp. 66-69 ◽  
Author(s):  
Hai Sheng Xie ◽  
Andrew I. Hsiao ◽  
William A. Quick
Keyword(s):  
Light Intensity ◽  
Experimental Period ◽  
Light Treatment ◽  
Avena Fatua ◽  
Herbicidal Activity ◽  
Growth Stages ◽  
Wild Oat ◽  
Low Light ◽  
Better Than

Growth chamber and greenhouse studies were conducted to evaluate effects of long-term low-light intensity on wild oat control with imazamethabenz and fenoxaprop. Seventy percent shading imposed during the entire experimental period resulted in enhanced activities for both herbicides applied at early and later growth stages. Such shading also reduced wild oat regrowth following application of imazamethabenz and fenoxaprop. When applied to plants exposed to 70 to 90% prespraying shading, both herbicides had phytotoxicity similar to, or better, than plants grown under continuous shading. Postspraying shading has less effect on herbicidal activity than prespraying shading or prolonged shading, especially with imazamethabenz. Full-light treatment more adversely affected fenoxaprop activity than imazamethabenz activity.

Seasonal Growth Studies of Intertidal Gastropods From Shell Micro-Growth Band Measurements, Including A Comparison With Alternative Methods

1984 ◽  
Vol 64 (1) ◽  
pp. 183-210 ◽  
Author(s):  
S. U. K. Ekaratne ◽  
D. J. Crisp
Keyword(s):  
Growth Rate ◽  
Shell Growth ◽  
Alternative Methods ◽  
Seasonal Growth ◽  
Nucella Lapillus ◽  
Growth Band ◽  
Growth Studies ◽  
Early Autumn ◽  
Short And Long Term

Tidal micro-growth bands were used to study the annual cycle of shell growth of individuals dated predominantly by the immersion mark technique, in three common intertidal gastropods Nucella lapillus (L.), Littorina littorea (L.) and Patella vulgata L. growing naturally in the Menai Straits. Growth in all three species approximated to the von Bertalanaffy type. All three species grew throughout the year, N. lapillus and L. littorea with early autumn and summer maxima, respectively, and P. vulgata with two maxima, one in late spring and the other in early autumn. P. vulgata alone were observed during exposure to a 6-day period of sub-zero air temperature in January 1982 when shell growth was totally interrupted. In Nucella and Littorina shell growth was found to be closely related to ambient temperature but in Patella there was a summer depression in growth. The file technique when combined with the immersion mark technique in date marking, was found to be inferior to the immersion mark technique on its own, since filing occasionally affected growth adversely.From among the factors determining the seasonal changes in growth rate, temperature was of major importance. Seasonal reproduction may also have an influence, especially in P. vulgata where gametogenesis coincides with the depression in growth rate during summer months.Alternative methods used in gastropod growth studies were compared. In the light of inadequacies associated with other methods of measuring growth, micro-growth band measurements in gastropods offers a new method with high resolution suitable both for short and long-term growth studies. It has potential also for ecological and physiological aspects of growth measurements.

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