Growth and survival of the native oyster Crassostrea gasar cultured under different stocking densities in two grow-out systems in tropical climate

ABSTRACT Survival and growth of the native oyster Crassostrea gasar along the juvenile and adult phases were evaluated in three different stocking densities [low (D), medium (2D) and high (3D)] and in two grow-out systems (fixed and floating system). The fixed system consisted of a rack made with PVC, fixed from the bottom with wood sticks. The floating system consisted of floating bags suspended by a rack made with PVC and maintained submerged from the seawater surface by eight floats. Survival and shell height of oysters cultured after 30, 60 and 90 days were registered in each phase and in each grow-out system. Results showed that the grow-out system did not affect survival and growth of C. gasar in the juvenile and adult phases. The tested densities affected the survival of oysters cultured over time in both phases but did not affect oyster growth. At times analyzed, it was observed positive growth in juvenile oysters grow after 90 days of culture. However, in the adult phase, no growth was observed after 90 days of culture. Oyster yield was higher in the density 3D, in both juvenile and adult phases. These findings contributed to the development of the oyster C. gasar culture.

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Prunus Africana Provenances Growth and Survival Evaluation in the Highland of Awi zone, Amhara Region, North Western Ethiopia

10.20944/preprints201801.0174.v1 ◽

2018 ◽

Author(s):

Abraham Demekristos

Keyword(s):

Light Exposure ◽

Seedling Survival ◽

Block Design ◽

Soil Water Potential ◽

Mean Value ◽

Good Growth ◽

Growth And Survival ◽

Prunus Africana ◽

Survival And Growth ◽

Establishment Rate

The aims of the study were to evaluate seedling growth and survival of Prunus africana provenances in awi highland based on ecological requirement of the tree. We measured survival and growth of three P.africana provenances seedlings found in Ethiopia (provenances sources namely: Gedeo, Jibat and Munnessa). Design of experiment with randomized complete block design (RCBD) with three replications. Seedlings planted at 2m, 2.5m and 3m distance between plants, plot, and blocks respectively. A plot size of 10mx10m and 25 plants are found per plot (0.01ha). We used ANOVA to test differences in survival, and growth among provenances over time. Results concluded that, provenances have no significant variation among in establishment rate, plant height and collar diameter growth. Of these provenances, Jibat was the first in establishment (56%), second in height (1.97m) and diameter (2.89cm). Gedeo was stood first in height (2.30m) but second in establishment rate (52%) and thickness(3.45cm), but Munessa with very good growth in diameter(3.59cm) might be prefreed for bark extraction followed by Gedeo, last in height (1.75m),but established second (52%). Contrary to expectations, seedlings were still at substantial risk of mortality ≥3 years after planting. Probably the plants survival rate and growth probably affected by altitude, soil water potential, light exposure, and wild animal presence in the surrounding. In steep slope sites, canopy shade, existing weed vegetation as well as wild animals such as apes is unlikely to enhance seedling survival after planting. Our results suggest that seedling mean growth increased with 0.008mm thickness and 0.41mm per day while 2.8mm thickness and 146.8mm tall increment recorded in 2560meter elevated high land or injibara with mean value of 18.5°C and rain fall is 1300mm.

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Immunocrit, colostrum intake, and preweaning body weight gain in piglets after split suckling based on birth weight or birth order1

Translational Animal Science ◽

10.1093/tas/txz131 ◽

2019 ◽

Vol 3 (4) ◽

pp. 1460-1465 ◽

Cited By ~ 2

Author(s):

Jodi M Morton ◽

Austin J Langemeier ◽

Theresa J Rathbun ◽

Duane L Davis

Keyword(s):

Body Weight ◽

Birth Weight ◽

Birth Order ◽

Body Weight Gain ◽

Growth And Survival ◽

Prenatal Growth ◽

Short Period ◽

Survival And Growth ◽

Improve Access ◽

Preweaning Period

Abstract Preweaning survival and growth are compromised in litters with larger numbers of piglets. We evaluated two approaches for altering initial nursing with the goal to improve access to colostrum by groups of piglets that are known to have reduced access to colostrum. Therefore, we temporarily (1.5 h) removed either the heaviest six piglets in the litter (WT) or the first half of the piglets born (ORD) to provide a short period of nursing with reduced competition for the remaining piglets. We found that WT piglets were heavier (P ≤ 0.05) at 7 d after farrowing and gained more body weight (BW) from farrowing to day 7 than control (CON) piglets which were raised in litters with ad libitum nursing during the same period. Further, we found that the heaviest piglets consumed more (P < 0.001) colostrum and gained more (P < 0.001) BW during the preweaning period but did not have (P > 0.10) greater immunocrits. Although ORD piglets had similar colostrum intake, immunocrits, and preweaning weights as controls, we found that overall the piglets born in the first half of litters had greater (P < 0.01) immunocrits than piglets born in the last half of the litter. Therefore, both birth weight and birth order have effects on traits that are important for prenatal growth and survival, but they differ in that birth weight is more closely related to colostrum intake and birth order affects immunocrit.

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Early Survival and Growth of Russian Pinus sylvestris L. in Canada

The Forestry Chronicle ◽

10.5558/tfc46325-4 ◽

1970 ◽

Vol 46 (4) ◽

pp. 325-328

Author(s):

A. H. Teich ◽

M. J. Holst

Keyword(s):

Pinus Sylvestris ◽

Scots Pine ◽

High Performance ◽

Jack Pine ◽

Stem Form ◽

Growth And Survival ◽

Growing Seasons ◽

Survival And Growth ◽

Continental Climate ◽

Better Than

Scots pine provenances from Russia were grown in Ontario at Longlac, Dorset and Chalk River, and in Saskatchewan at Prince Albert and Indian Head. After eight growing seasons in the field all provenances survived well. The three tallest, Orel, Woronesh and Kiev provenances, grew considerably taller than the others, and at Prince Albert, where native jack pine was also grown, the growth and survival of these provenances was also better than that of jack pine. If further studies show that this high performance persists and that stem form is commercially acceptable, seedlings from these three provenances may be useful for reforestation in those parts of Canada with a continental climate.

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Growth and survival of the pearl oyster Pteria hirundo (L.,1758) in an intermediate stage of culture in Santa Catarina, Brazil

Brazilian Journal of Biology ◽

10.1590/s1519-69842012000100021 ◽

2012 ◽

Vol 72 (1) ◽

pp. 175-180 ◽

Cited By ~ 3

Author(s):

MCP Albuquerque ◽

R Alves ◽

ACV Zanandrea ◽

JF Ferreira ◽

CMR Melo ◽

...

Keyword(s):

Culture System ◽

Intermediate Stage ◽

Pearl Oyster ◽

Average Increase ◽

Southern Brazil ◽

Growth And Survival ◽

Life Conditions ◽

Pearl Oysters ◽

Survival And Growth ◽

Closed Environment

There are no records in Brazil for the culture of Pteridae family oysters, genus Pteria and Pinctada. The intermediate culture can be considered one of the critical stages during the oyster farming. The changes in life conditions from a semi-closed environment provided by the collector to the structures utilized for the growth represents a considerable stress factor to which the animals are subjected. The goal of the present study was to evaluate the growth and survival of the pearl oyster Pteria hirundo (Linnaeus, 1758) kept in intermediate lanterns. Seeds of P. hirundo, obtained through larviculture carried out at the Marine Molluscs Laboratory (UFSC), southern Brazil were detached from the collectors, transferred and kept in an intermediate culture system (oyster lantern). During 6 months, growth (dorso-ventral height - DVH in mm) and survival (%) were evaluated. Two size classes were tested: medium (M), between 3.4 and 4.4 mm, and large (L), bigger than 4.5 mm. The density of occupation in each floor of the lantern was 50%. At the end of the experiment, the survivals observed were 90 and 94% for the sizes M and L, respectively. Medium juveniles of Pteria hirundo had an average (Std) increase of 16.1 (±4.38) mm in the dorso-ventral height, and large juveniles an average increase of 11.4 (±3.77) mm after six months of experiment. The results observed during the intermediate stage of cultivation indicate that Pteria hirundo presents survival and growth similar to other species of pearl oysters traditionally used in the pearl industry in several countries.

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Change in wild-oyster assemblages of Port Stephens, NSW, Australia, since commencement of non-native Pacific oyster (Crassostrea gigas) aquaculture

Marine and Freshwater Research ◽

10.1071/mf09177 ◽

2010 ◽

Vol 61 (6) ◽

pp. 714 ◽

Cited By ~ 22

Author(s):

Melanie J. Bishop ◽

Fredrick R. Krassoi ◽

Ross G. McPherson ◽

Kenneth R. Brown ◽

Stephen A. Summerhayes ◽

...

Keyword(s):

Crassostrea Gigas ◽

Pacific Oyster ◽

New South ◽

Shell Height ◽

Larval Transport ◽

South Wales ◽

Circulation Patterns ◽

Fouling Assemblages ◽

Native Oyster ◽

Port Stephens

Proliferation of species introduced for aquaculture can threaten the ecological and economic integrity of ecosystems. We assessed whether the non-native Pacific oyster, Crassostrea gigas, has proliferated, spread and overgrown native Sydney rock oysters, Saccostrea glomerata, in Port Stephens, New South Wales (NSW), Australia, following the 1991 decision to permit its aquaculture within this estuary. Sampling of seven rocky-shore and four mangrove sites immediately before (1990), immediately after (1991–1992) and nearly two decades after (2008) the commencement of C. gigas aquaculture did not support the hypotheses of C. gigas proliferation, spread or overgrowth of S. glomerata. The non-native oyster, uncommon immediately before the commencement of aquaculture, remained confined to the inner port and its percentage contribution to oyster assemblages generally declined over the two decades. C. gigas populations were dominated by individuals of <40-mm shell height, with established adults being rare. Only at one site was there an increase in C. gigas abundance that was accompanied by S. glomerata decline. The failure of C. gigas in Port Stephens to cause the catastrophic changes in fouling assemblages seen elsewhere in the world is likely to reflect estuarine circulation patterns that restrict larval transport and susceptibility of the oysters to native predators.

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Embryonic exposure to conspecific chemicals suppresses cane toad growth and survival

Biology Letters ◽

10.1098/rsbl.2011.0794 ◽

2011 ◽

Vol 8 (2) ◽

pp. 226-229 ◽

Cited By ~ 20

Author(s):

Michael R. Crossland ◽

Richard Shine

Keyword(s):

Chemical Cues ◽

Ecological Impacts ◽

Cane Toad ◽

Growth And Survival ◽

Rhinella Marina ◽

Embryonic Exposure ◽

Body Sizes ◽

Tropical Australia ◽

Survival And Growth ◽

Invasive Taxa

Adaptations to suppress the viability of conspecifics may provide novel ways to control invasive taxa. The spread of cane toads ( Rhinella marina ) through tropical Australia has had severe ecological impacts, stimulating a search for biocontrol. Our experiments show that cane toad tadpoles produce waterborne chemical cues that suppress the viability of conspecifics encountering those cues during embryonic development. Brief (72 h) exposure to these cues in the egg and post-hatching phases massively reduced rates of survival and growth of larvae. Body sizes at metamorphosis (about three weeks later) were almost twice as great in control larvae as in tadpole-exposed larvae. The waterborne cue responsible for these effects might provide a weapon to reduce toad recruitment within the species' invaded range.

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Industrial Research and Firm Size, Survival, and Growth in American Manufacturing, 1921–1946: An Assessment

The Journal of Economic History ◽

10.1017/s0022050700030837 ◽

1983 ◽

Vol 43 (4) ◽

pp. 953-980 ◽

Cited By ~ 56

Author(s):

David C. Mowery

Keyword(s):

Firm Size ◽

Small Firms ◽

Firm Growth ◽

Industrial Research ◽

Large Firms ◽

Research Activity ◽

Growth And Survival ◽

Survival And Growth ◽

The Impact ◽

The Relationship

The literature on the development of American industrial research suggests that during the twentieth century large firms “dominated” industrial research, and reaped the majority of the benefits from such activity. This paper utilizes new data to analyze both the relationship between firm size and research employment and the impact of research activity on firm growth and survival during 1921–1946. The results suggest that large firms were no more research-intensive than were small firms during the 1921–1946 period. Research activity significantly enhanced the probability of firms' survival among the ranks of the 200 largest manufacturing firms during 1921–1946. Research employment also improved the growth performance of both large and small firms during 1933–1946.

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Effects of Environment on Growth and Survival of Douglas-fir Transplants

Canadian Journal of Forest Research ◽

10.1139/x74-029 ◽

1974 ◽

Vol 4 (2) ◽

pp. 193-200

Author(s):

E. B. Tregunna ◽

M. Crown

Keyword(s):

Storage Time ◽

Water Status ◽

Douglas Fir ◽

Planting Date ◽

Growth And Survival ◽

Lower Elevation ◽

Survival And Growth ◽

And Storage ◽

Root Treatment ◽

Spring Planting

Variation in lifting date, planting date, planting site, seedling history, root treatment, and storage time were tested for their effects on Douglas-fir transplants. Survival, water status, types of damage, and both shoot and root growth were measured. Survival decreased with later spring planting date in the field, but this was partly offset by trends in browsing. Survival was greater at the lower elevation. Differences in seed lot, or conditions in the nursery, resulted in differences in tree size, which had some effects because the larger trees were browsed more. Survival and growth were not markedly different between root treatments. Cold storage increased survival of trees lifted late in the spring. The relative turgidity of leaves from bareroot trees in storage was related to lifting date and subsequent survival. Survival decreased severely as lifting date progressed through March.

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Demographic consequences of climate variation along an elevational gradient for a montane terrestrial salamander

10.1101/130922 ◽

2017 ◽

Author(s):

Nicholas M. Caruso ◽

Leslie J. Rissler

Keyword(s):

Survival Rates ◽

Elevational Gradient ◽

Vital Rates ◽

Life History Variation ◽

Growth And Survival ◽

Active Season ◽

Asymptotic Size ◽

Capture Recapture ◽

Survival And Growth ◽

The Relationship

AbstractClimate change represents a significant threat to amphibians, which are already imperiled. However, for many species, the relationship between demographic vital rates (survival and growth) and climate is unknown, which limits predictive models. Here we describe the life history variation ofPlethodon montanususing capture-recapture data over a period of four years, at five sites along an elevational gradient to determine how survival and growth vary with temperature, precipitation, and how these relationships vary with elevation. We used a hierarchical model to estimate asymptotic size and growth rate, and used a spatial Cormack-Jolly-Seber model to estimate probability of capture and survival, as well as dispersal variance. Our results show that during the active season, growth and survival rates are both positively affected by precipitation, while survival was positively affected by temperature at all elevations, the relationship between growth rates and temperature varied along the elevational gradient. Generally at lower elevations, higher temperatures led to a decrease in growth while at higher elevations the opposite was true. During the inactive season we found elevational variation in the relationship between survival and the amount of snow; at low elevations snowfall was low but survival decreased with increasing snowfall while at higher elevations increasing snowfall lead to higher survival. Our results demonstrate that understanding how the environment can affect salamander demography to develop mechanistic models, will require knowledge of the actual environmental conditions experienced by a given population as well as an understanding of the overall differences in climate at a given site.

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Survival and growth of white poplar rooted cuttings regarding term of planting

Topola ◽

10.5937/topola2005033k ◽

2020 ◽

pp. 33-46

Author(s):

Branislav Kovačević ◽

Dušan Igić ◽

Zoran Novčić ◽

Saša Orlović

Keyword(s):

Populus Alba ◽

White Poplar ◽

Rooted Cuttings ◽

Growth And Survival ◽

Nursery Production ◽

Sources Of Variation ◽

Standard Term ◽

Survival And Growth ◽

Positive Effect ◽

Rooting Capacity

White poplar nursery production is mainly based on vegetative propagation hardwood cuttings. In this study the reaction of three clones of white poplar (Populus alba L.) on term of cuttings' preparation and planting according to parameters of survival and growth of rooted cuttings in three nurseries in Northern part of Serbia. There were two terms of cuttings' preparation and planting examined: a) mid-March and d) the beginning of April (standard term). Obtained results suggest considerable differences between nurseries and between examined terms. Differences between clones were not significant, but there were found significant effects of interactions of factor Clone with other two main sources of variation. The best results were obtained by cuttings that were prepared and planted in mid-March, due to faster growth and survival of rooted cuttings. The positive effect of the earlier term is evident particularly in clones L-12 and L-80 and enable feasible production of rooted cuttings of these clones, especially in nurseries that obtained better conditions. Results obtained in this study suggest that influence of terms of cuttings' production and planting is important issue concerning introduction of clones with relatively poor rooting capacity, optimization of nursery technology of experimental white poplar clones, and improvement of white poplar nursery production in general.

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