Age Estimation and Growth-Rates of Captive and Wild Pouch Young of Petrogale-Assimilis

1990 ◽  
Vol 17 (5) ◽  
pp. 491 ◽  
Author(s):  
R Delaney ◽  
G Death
Keyword(s):  
Growth Rates ◽  
Age Estimation

Growth and age validation of Rainbow Trout, Oncorhynchus mykiss (Walbaum)' in Lake Eucumbene, NSW

1992 ◽  
Vol 43 (5) ◽  
pp. 1033 ◽  
Author(s):  
RA Faragher
Keyword(s):  
Rainbow Trout ◽  
Oncorhynchus Mykiss ◽  
Growth Rates ◽  
Age Estimation ◽  
New South ◽  
Age Validation ◽  
Scale Reading ◽  
Rainbow Trout Oncorhynchus Mykiss ◽  
South Wales ◽  
Second Year

Growth rates of finclipped rainbow trout (Oncorhynchus mykiss) released into Lake Eucumbene, New South Wales, at an age of 0+ years were examined for each year between 1986 and 1988. Traps and nets yielded significant numbers of marked fish for validation of age estimation and length backcalculation from scale reading. Poor recognition of the marks by anglers was confirmed, indicating that survival of the fish was higher than was implied by angling returns. The diffuse nature of the second annulus in scales provided initial difficulty in ageing, particularly because of a similarly diffuse false check formed during the second year. Care was required in separating the annuli after asymptotic growth was reached (3 years), Growth rates in Lake Eucumbene were comparable with those found in studies in Tasmania and Victoria. Back-calculated lengths were in agreement with those from fish of known ages. The presence of finclipped fish aged 2 + and 3 + years in a spawning population confirmed that stocked fish contributed to the spawning stocks. The study reconfirms the importance of validation of ageing techniques in fisheries investigations.

Age Estimation, Growth Rates, and Population Structure in Missouri Bullfrogs

Copeia ◽  
1968 ◽  
Vol 1968 (3) ◽  
pp. 583 ◽  
Author(s):  
Eugene E. Schroeder ◽  
Thomas S. Baskett
Keyword(s):  
Population Structure ◽  
Growth Rates ◽  
Age Estimation

scholarly journals Age and growth of Niagara River Lake Sturgeon

2020 ◽  
Author(s):  
Jonah L Withers ◽  
Dimitry Gorsky ◽  
Zy Biesinger ◽  
Donald Einhouse ◽  
Michael Clancy ◽  
...  
Keyword(s):  
Age Structure ◽  
Growth Rates ◽  
Age Estimation ◽  
Stock Assessment ◽  
Lake Sturgeon ◽  
Age And Growth ◽  
Individual Growth ◽  
Estimation Accuracy ◽  
Niagara River ◽  
Age Estimates

Knowledge of the distribution of ages of fish within a stock, and subsequently individual growth rates, allows managers the ability to calculate key metrics (i.e., recruitment, mortality, and stock growth rate) that greatly improve stock assessment models. Two remnant stocks of Lake Sturgeon Acipenser fulvescens exist near and within the Niagara River; one primarily occupying the headwaters of the river and the other primarily occupying the mouth of the river. Though initial efforts in the late 1990s collected data on the lower Niagara River stock, a long-term, comprehensive examination of age and growth is lacking and the age structure of the stock found at the headwaters has yet to be formally described to our knowledge. To ascertain the current age structure of these two stocks we sampled Lake Sturgeon in the lower Niagara River and at the headwaters of the Niagara River between 2012 and 2017 and took a portion of the leading pectoral fin spine of captured Lake Sturgeon for age estimation. Ages ranged between 4 and 42 years with females generally being older and larger than males. The median age appeared to increase from 14 to 18 years old throughout our study in both stocks. Lengths-at-age of both stocks were larger than those reported in other systems and growth rates appear to have increased over the past decade in the lower Niagara River. Despite efforts to improve age estimation accuracy, age estimates from fish whose ages were partly-known (derived from multiple age estimates from fish that were captured multiple times) demonstrated assigned ages may have greater error than expected. Additionally, a lack of young individuals confounded growth analyses. Although there was uncertainty in the assigned ages, this study still provides evidence of consistent recruitment in both stocks and, to our knowledge, the first characterization of the age structure of the Lake Sturgeon stock occupying the headwaters of the Niagara River.

scholarly journals Age relationships with telomere length, body weight and body length in wild dugong (Dugong dugon)

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10319
Author(s):  
Phaothep Cherdsukjai ◽  
Kittisak Buddhachat ◽  
Janine Brown ◽  
Manthanee Kaewkool ◽  
Anocha Poommouang ◽  
...  
Keyword(s):  
Body Weight ◽  
Telomere Length ◽  
Growth Rates ◽  
Age Estimation ◽  
Telomere Attrition ◽  
Growth Status ◽  
Alternative Approach ◽  
Basic Biology ◽  
Layer Groups ◽  
Free Ranging

The ability to estimate age and determine the growth status of free-ranging dugongs (Dugong dugon) is vital to providing insight into the basic biology of this endangered species. Currently, age estimation in dugong carcasses relies on counting dentin growth layer groups (GLGs) in tusks, but a disadvantage is they need to be intact. We explored whether measures of telomere length could be used as an alternative approach to age estimation in dugongs given that in other species, telomere length and age are inversely related. In this study, relative telomere length (rTL) was measured by qPCR in skin samples from 24 dugongs of varying ages determined by counts of GLGs. In addition, relationships between age by GLG counts and body weight and length and were examined. Our findings indicate that age estimated by GLGs was negatively correlated with telomere length using the logistic formula with a rate of telomere attrition of approximately 0.036 rTL/year between the ages of 5–20 years. By comparison, both body weight and length were positively correlated with GLG-based age, with growth rates of ~8.8 kg/year for weight and ~3.58 cm/year for length, respectively. After that, growth rates slowed substantially and then plateaued. The results suggest that physical maturity in dugongs occurs at 20 years of age and that measures of rTL might serve as a tool for age estimation in dugongs, living and deceased.

Age estimation by measurement of pouch young of the Quokka (Setonix brachyurus).

1961 ◽  
Vol 9 (1) ◽  
pp. 14 ◽  
Author(s):  
JW Shield ◽  
P Woolley
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Nutritional Status ◽  
Growth Rates ◽  
Age Estimation ◽  
Tail Length ◽  
Estimation Procedure ◽  
Full Term ◽  
Male And Female ◽  
Young Growth

Removal of pouch young of Setonix can lead to the resumption of development of quiescent blastocysts. Thirty-six pouch young obtained in this way have been used in this study. As the time in days from resumption of development to parturition is known, accurate ages may be calculated without actual birth or copulation being observed. These 36 animals have been repeatedly measured during their pouch life, and body weight, pes length, and tail length over the full term of pouch occupancy are given as regressions of these measures versus age. Larger-scale regressions are given for the first 80 days of pouch life. A tabulation based on the three regressions and giving average measures at stated ages is also given. During pouch life there is no difference in growth rate between male and female pouch young. Growth proportions of field-reared and compound-reared animals of comparable nutritional status are also similar. It is therefore considered that growth rates are equal, and that the age-estimation procedure established on compound-reared animals is applicable to field animals.

Reduced growth rates of hair in mice following radiation

1966 ◽  
Vol 94 (4) ◽  
pp. 491-498 ◽  
Author(s):  
F. D. Malkinson
Keyword(s):  
Growth Rates

Institutional Theory of Endless Redistribution

2005 ◽  
pp. 4-18 ◽  
Author(s):  
K. Sonin
Keyword(s):  
Property Rights ◽  
Institutional Theory ◽  
Growth Rates ◽  
Rent Seeking ◽  
Economic Institutions ◽  
Wide Spread ◽  
Grass Roots ◽  
Protection Systems ◽  
Private Protection ◽  
The Rich

In unequal societies, the rich may benefit from shaping economic institutions in their favor. This paper analyzes the dynamics of institutional subversion by focusing on public protection of property rights. If this institution functions imperfectly, agents have incentives to invest in private protection of property rights. The ability to maintain private protection systems makes the rich natural opponents of public protection of property rights and precludes grass-roots demand to drive the development of the market-friendly institution. The economy becomes stuck in a bad equilibrium with low growth rates, high inequality of income, and wide-spread rent-seeking. The Russian oligarchs of the 1990s, who controlled large stakes of newly privatized property, provide motivation for this paper.

Waiting for a New Model of Growth: Russia’s Social and Economic Development in 2013

2014 ◽  
pp. 4-32 ◽  
Author(s):  
V. Mau
Keyword(s):  
Economic Policy ◽  
Economic Development ◽  
Economic Performance ◽  
Growth Rates ◽  
Global Crisis ◽  
New Model ◽  
Social And Economic Development ◽  
Economic Risks

The paper deals with Russian social and economic development in 2013 and prospects for the next year or two. The author discusses the logic and trends of the global crisis started in 2008. This is the basis for further analysis of current Russian economic performance with special emphasis on the problem of growth rates deceleration. Special attention is paid to economic risks and priorities of economic policy.

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