GROWTH STUDIES OF REINDEER FAWNS

1962 ◽  
Vol 40 (5) ◽  
pp. 863-869 ◽  
Author(s):  
Charles J. Krebs ◽  
I. McT. Cowan
Keyword(s):  
Growth Rates ◽  
Growth Pattern ◽  
Early Growth ◽  
Mackenzie Delta ◽  
Age Classes ◽  
Natural Conditions ◽  
Rate Of Growth ◽  
Growth Studies ◽  
Weight Data ◽  
Wild Reindeer

A study of the growth of reindeer fawns was carried out during the spring and summer of 1958 in the Mackenzie Delta, N.W.T. Growth rates were obtained for four fawns under natural conditions. Early growth of the fawns (0–2 months) can usually be divided into three phases and some possible reasons for this are given. The rate of growth of reindeer fawns is slightly less than that of Columbian black-tailed deer fawns. Some weight data for different sex and age classes of wild reindeer are given, and it is concluded that the Mackenzie Delta reindeer do not differ greatly in growth pattern from Russian reindeer.

The Winter Flounder (Pseudopleuronectes americanus) in Long Pond, Conception Bay, Newfoundland

1971 ◽  
Vol 28 (8) ◽  
pp. 1153-1165 ◽  
Author(s):  
V. S. Kennedy ◽  
D. H. Steele
Keyword(s):  
Food Intake ◽  
Growth Rates ◽  
Plant Material ◽  
Early Growth ◽  
Winter Flounder ◽  
Pseudopleuronectes Americanus ◽  
Food Items ◽  
Fish Remains ◽  
Males And Females ◽  
Conception Bay

Monthly samples of winter flounder taken in Long Pond from November 1962 to October 1963 indicated that the flounder moved into deeper water (7–10 m) during the summer and returned to shallow water (1–2 m) from September to June. These movements corresponded to the end of the spawning season and the ripening of the gonads respectively. Spawning occurred from March until early June, most of it in May and early June. Most males were mature at age 6 and most females at age 7. Fifty percent of the males and females were mature at 21 and 25 cm respectively. The growth rates of the males and females were similar until the age of 8, after which the females apparently outgrew the males. Early growth and fecundity were similar to those reported for other areas. No feeding took place in December or January but the flounder fed in March and continued to feed throughout the summer; food intake decreased in the fall. They were omnivorous and the type of food eaten varied with the locality. Polychaetes, plant material, and molluscs were the most common food items throughout the year. Capelin eggs and fish remains were found only during a few months of the year but were eaten in great quantities.

A population birth-and-mutation process, I: explicit distributions for the number of mutants in an old culture of bacteria

1974 ◽  
Vol 11 (03) ◽  
pp. 437-444 ◽  
Author(s):  
Benoit Mandelbrot
Keyword(s):  
Growth Rate ◽  
Mutation Rate ◽  
Growth Rates ◽  
Random Variable ◽  
Mutation Process ◽  
Limit Condition ◽  
Rate Of Growth ◽  
Mathematical Techniques ◽  
First Time

Luria and Delbrück (1943) have observed that, in old cultures of bacteria that have mutated at random, the distribution of the number of mutants is extremely long-tailed. In this note, this distribution will be derived (for the first time) exactly and explicitly. The rates of mutation will be allowed to be either positive or infinitesimal, and the rate of growth for mutants will be allowed to be either equal, greater or smaller than for non-mutants. Under the realistic limit condition of a very low mutation rate, the number of mutants is shown to be a stable-Lévy (sometimes called “Pareto Lévy”) random variable, of maximum skewness ß, whose exponent α is essentially the ratio of the growth rates of non-mutants and of mutants. Thus, the probability of the number of mutants exceeding the very large value m is proportional to m –α–1 (a behavior sometimes referred to as “asymptotically Paretian” or “hyperbolic”). The unequal growth rate cases α ≠ 1 are solved for the first time. In the α = 1 case, a result of Lea and Coulson is rederived, interpreted, and generalized. Various paradoxes involving divergent moments that were encountered in earlier approaches are either absent or fully explainable. The mathematical techniques used being standard, they will not be described in detail, so this note will be primarily a collection of results. However, the justification for deriving them lies in their use in biology, and the mathematically unexperienced biologists may be unfamiliar with the tools used. They may wish for more details of calculations, more explanations and Figures. To satisfy their needs, a report available from the author upon request has been prepared. It will be referred to as Part II.

The Relative Growth of Parts in Palaemon Carcinus

1930 ◽  
Vol 7 (2) ◽  
pp. 165-174
Author(s):  
M. A. TAZELAAR
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Linear Measurements ◽  
Relative Growth ◽  
Male And Female ◽  
Relative Growth Rates ◽  
Rate Of Growth ◽  
The Difference ◽  
Rates Of Growth

Linear measurements of certain appendages and the carapace of P. carcinus were made and plotted in various ways. The following conclusions were drawn: 1. The cheliped shows heterogonic growth in both male and female, but more markedly in the male, the values of k being: male 1.8 and female 1.48 2. The pereiopods in both male and female are slightly heterogonic. The relative growth rates are graded from p3 to p5, that of p3 being slightly greater than that of p5 3. Of the ordinary pereiopods the rate of growth of p1 is the smallest in the male, but the largest in the female. 4. The difference between the rates of growth of p1 and p3 in male and female is greatest where the rate of growth in the heterogonic organ, the cheliped, is most excessive in the male. 5. The growth of the 3rd maxilliped is slightly negatively heterogonic, the value of k in the male being 0.93 and in the female 0.95. Hence there seems to be a correlation between the marked heterogony in the cheliped on the growth rate of neighbouring appendages. In those immediately posterior to the cheliped the growth rate is increased and in those anterior decreased.

scholarly journals Variations in early life history traits of Japanese anchovy Engraulis japonicus in the Yangtze River Estuary

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4789 ◽  
Author(s):  
Chunlong Liu ◽  
Weiwei Xian ◽  
Shude Liu ◽  
Yifeng Chen
Keyword(s):  
Growth Rates ◽  
Early Life ◽  
Yangtze River ◽  
Life History Traits ◽  
River Estuary ◽  
Early Life History ◽  
Early Growth ◽  
Yangtze River Estuary ◽  
Japanese Anchovy ◽  
The Yangtze River Estuary

Resources of Japanese anchovy (Engraulis japonicus Temminck & Schlegel, 1846) are undergoing dramatic recessions in China as the consequence of intensifying anthropogenic activities. Elucidating the influences of local-scale environmental factors on early life history traits is of great importance to design strategies conserving and restoring the declining anchovy resources. In this research, we studied hatching date and early growth of anchovy in the Yangtze River Estuary (YRE) using information obtained from otolith microstructure. Onset of hatching season and growth rates of anchovy was compared to populations in Japan and Taiwan. In YRE, the hatching date of anchovy ranged from February 26th to April 6th and mean growth rate ranged from 0.27 to 0.77 mm/d. Anchovies hatching later had higher growth rates than individuals hatching earlier before the 25th day. Among populations, hatching onsets of anchovy from the higher latitude were later than populations in the lower latitude, and growth rates of anchovy in YRE were much lower than populations in Japan and Taiwan. Variations in hatching onsets and early growth patterns of anchovy thus provide important knowledge on understanding the adaptation of anchovy in YRE and designing management strategies on conserving China’s anchovy resources.

scholarly journals Tissue composition and allometric growth of tissues from commercial cuts and carcass of Texel lambs slaughtered with different weights

2016 ◽  
Vol 37 (4) ◽  
pp. 2123 ◽  
Author(s):  
Sérgio Carvalho ◽  
Luana Cortes Zago ◽  
Cleber Cassol Pires ◽  
Andressa Ana Martins ◽  
Rafael Sanches Venturini ◽  
...  
Keyword(s):  
Growth Pattern ◽  
Early Growth ◽  
Tissue Growth ◽  
The Other ◽  
Tissue Composition ◽  
Allometric Growth ◽  
Slaughter Weight ◽  
Muscle Tissues ◽  
Late Growth

In this study, we evaluated the tissue composition, the ratios between different issues, and the allometric growth of tissues from the commercial cuts neck, shoulder, rib, and leg, and of the carcass of Texel lambs. Thirty uncastrated male lambs born from single calvings were used in this experiment. Lambs were weaned, confined individually, and distributed into five treatments with six replications. Each treatment consisted of a predefined slaughter weight (T23 – initial slaughter, T25, T30, T35, and T40). The proportion of bone decreased linearly in the shoulder, rib, and legs, but remained constant in the neck. The proportion of muscle decreased in the rib, whereas in the other cuts it remained constant. The percentage of fat increased as the slaughter weight of the lambs was increased, for all cuts. In all cuts and in the carcass, bone and muscle showed early growth (b < 1), whereas fat displayed late growth (b > 1). The proportion of bone decreased and fat increased linearly in the carcass, and the proportion of muscle was not influenced by the slaughter weight of the lambs. The muscle/fat ratio decreased in all cuts, and consequently in the half-carcass, as the slaughter weight was increased. The muscle/ bone ratio increased in the shoulder, rib, leg, and half-carcass, but there was no significant effect on the neck. The bone and muscle tissues showed early growth, whereas the fat had late growth in the different commercial cuts and carcass of Texel lambs. The tissue growth pattern of the shoulder may be representative of the allometric growth of the different carcass tissues. An increase in the slaughter weight of Texel lambs leads to a reduction of the muscle/fat ratio, due to the higher deposition of fat in the carcass of these animals.

Development of the fibre population in N-type sheep.

1954 ◽  
Vol 5 (3) ◽  
pp. 490 ◽  
Author(s):  
AS Fraser ◽  
JM Ross ◽  
GM Wright
Keyword(s):  
Growth Rates ◽  
Fibre Type ◽  
Frequency Of Occurrence ◽  
Frequency Distributions ◽  
Rate Of Growth ◽  
Fibre Growth ◽  
Type Frequency ◽  
Primary Lateral

Several types of follicles occur in the skin of sheep. These have been shown to differ in the types of fibres they form, when these are classified on shape of tip curl, occurrence of medulla, size of crimps, rate of growth, and frequency of shedding as kemps. Fibre type frequency distributions have been analysed. In non-N-type, halo-hairs and fibres with a sickle-shaped tip, forming the pre-curly-tip group, can only be formed in primary central follicles, which ordinarily all grow pre-curly-tip fibres, although occasionally these follicles produce curly-tip fibres. The primary lateral follicles all grow curly-tip fibres which grow also in the early secondary follicles. The late secondary follicles grow fibres with a tip of indefinite shape, histerotrichs. In N-type sheep primary centrals always form pre-curly-tip fibres, with the reservation that in Plateau arrays with few or no fibres classed as supersickle- fibres it is believed that some fibres called hairy-tip–curly-tip fibres grow in primary central follicles; primary laterals form hairy-tip–curly-tip fibres save in some N/+ lambs; and the secondaries form curly-tip and histerotrich fibres. The primary follicles are strongly affected by the N and nr genes, which have much less effect, if any, on the secondaries. Fibre growth rates and consequently size of crimps, and frequency of occurrence of brown fibres and of shedding as kemps, are all higher in primary than in secondary fibres in N-type sheep, and in N-type than in non-N-type, showing that the N and nr genes affect the primary more than the secondary follicles in these characteristics.

Preliminary Observations on the Growth of Transplanted Peltigera Canina Under Semi-Natural Conditions

1997 ◽  
Vol 29 (1) ◽  
pp. 91-96 ◽  
Author(s):  
M. Webster ◽  
D. H. Brown
Keyword(s):  
Growth Rates ◽  
Linear Growth ◽  
Natural Conditions ◽  
Peltigera Canina

AbstractPeltigera canina thalli have been successfully transplanted onto soil in a garden and in flowerpots. Garden samples showed marked seasonality and achieved growth rates of 6·4 cm per year. Pot-grown samples showed variation in the growth of individual thallus lobes and established that, under different soil hydration regimes, permanently hydrated thalli could sustain considerable linear growth rates for at least 140 days.

Distribution and increment of biomass in adjacent young Douglas-fir stands with different early growth rates

1987 ◽  
Vol 17 (7) ◽  
pp. 722-730 ◽  
Author(s):  
Miguel A. Espinosa Bancalari ◽  
David A. Perry
Keyword(s):  
Growth Rates ◽  
Aboveground Biomass ◽  
Early Growth ◽  
Douglas Fir ◽  
Rooting Depth ◽  
Summer Drought ◽  
Total Biomass ◽  
Area Index ◽  
Biomass Increment ◽  
Anaerobic Soils

Total biomass increments were determined for three adjacent 22-year-old Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) plantations in the Oregon Coast Range that had widely different early growth rates. Estimated total aboveground biomass of the stands, designated slow, intermediate, and fast, was 98.7, 148.7, and 203.7 Mg•ha−1, respectively; estimated mean biomass increment in the 5 years previous to sampling was 8.9, 12.6, and 12.3 Mg•ha−1•year−1. The slow stand had a greater proportion of aboveground biomass in branches and a smaller proportion in stem wood than the intermediate and fast stands. Differences in biomass increment were primarily due to stem rather than crown growth. Total below ground biomass was highest in the fast stand, the difference being due to roots >5 mm in diameter; weight of roots <5 mm was greater in the slow and intermediate stands. Roots >5 mm comprised about 77% of the total root system in those stands and 90% in the fast stand. Increment of roots >5 mm was 2.2, 2.5, and 3.0 Mg•ha−1•year−1 in the slow, intermediate, and fast stands. The ratio of productivity to total leaf nitrogen suggests that nitrogen is a principal limiting resource in the intermediate stand. The fast stand, with a leaf area index 50% greater than the others, is probably limited by light. The slow stand has anaerobic soils during at least part of the year, which may restrict rooting depth and thereby induce water stress during summer drought.

Dormancy, germination and seedling growth of two Kalaharian perennials of the genus Harpagophytum (Pedaliaceae)

1988 ◽  
Vol 4 (2) ◽  
pp. 185-198 ◽  
Author(s):  
W. H. O. Ernst ◽  
T. Tietema ◽  
E. M. Veenendaal ◽  
R. Masene
Keyword(s):  
Gibberellic Acid ◽  
High Temperatures ◽  
Seedling Growth ◽  
Seed Coat ◽  
Growth Rates ◽  
Natural Conditions ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Respiration Rates ◽  
Drought Avoidance

ABSTRACTDormancy and germination ecology of two Harpagophytum species (Pedaliaceae) from an open Acacia savanna in Botswana were investigated. The maintenance of dormancy is governed partly by the seed coat but mainly by the endosperm and the embryo itself, as demonstrated by removal of the endosperm. Dissemination of the seed from the fruit can be delayed for several years without affecting the viability of the embryo, due to very low respiration rates.Germination can be enhanced slightly by high temperatures under natural conditions, and by gibberellic acid or removal of the endosperm under laboratory conditions. Relative growth rates for both Harpagophytum species are lower than for subtropical grasses and legumes, due to a strong investment in root and tuber biomass. Germination and seedling growth is discussed in relation to the drought avoidance syndrome and the animal disperser syndrome.

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