Some factors which affect the liveweight change and wool growth of adult Corriedale wethers grazed at various stocking rates on perennial pasture in southern Victoria.

1981 ◽  
Vol 32 (2) ◽  
pp. 353 ◽  
Author(s):  
HA Birrell
Keyword(s):  
Growth Rate ◽  
Regression Analysis ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Growth Rates ◽  
Stocking Rate ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Wool Growth ◽  
Stocking Rates

Monthly observations were taken on a number of animal and pasture characteristics during a 24-year study with adult Corriedale wethers which were grazed at 10, 15, 20 and 25 sheep ha-1. The seasonal patterns in all the observed parameters varied with the stocking rate. The more notable were the fluctuations in digestible organic matter intake (DOMI) which increased with stocking rate in summer (10 and 25 sheep ha-1 having 426 and 818 g DOMI d-1 respectively) and decreased in winter (655 and 448 g DOMI d-1). Both liveweight and wool growth rate (WGR) declined during autumn and increased in the spring at the two high stocking rates but not at the two low stocking rates. The herbage present and its relative growth rate both influenced the amount of herbage voluntarily eaten when the pasture was green. When the dry matter of herbage was < 1.5 t ha-1, the amount of herbage eaten increased as the yield and relative growth rates > 0.05 g g-1 d-1 increased. Sixty-two per cent of the variance in DOMI was accounted for. An exponential function fitted the overall data when relative growth rates were <0.05 g g-1 d-1. DOMI asymptoted at 740 g d-1 when herbage yields exceeded 2.0 t ha-1 (R2 = 0.70). Liveweight loss was very rapid in autumn at high stocking rates despite a high DOMI (c. 650g d-1). This was found, by using multiple regression analysis, to be associated with shearing stress, poor quality feed and long grazing times. In spring, on better quality feed, a long grazing time was associated with an enhanced liveweight response. A multiple regression analysis accounted for 73 % of the variance in WGR. The expression suggested that WGR increased and had a slightly curvilinear relationship with DOMI, was positively related to digestibility and negatively related to the daily time spent grazing. Wool growth slowed concurrently with liveweight losses, the magnitude of the decrease depending upon DOMI.

The effect of stocking rate and deferred Autumn grazing of pasture on liveweight and wool production of Merino wethers in a Mediterranean-type climate

1976 ◽  
Vol 16 (79) ◽  
pp. 189 ◽  
Author(s):  
TH Brown
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
South Australia ◽  
Management Systems ◽  
Research Centre ◽  
Stocking Rate ◽  
Wool Production ◽  
Wool Growth ◽  
The Cost ◽  
Stocking Rates

Liveweight, seasonal wool growth rates, annual wool production, wool quality and hand feeding requirements were recorded for Merino wethers when autumn deferred or continuously grazed. The two management systems were compared at a series of eight stocking rates from 12.4 to 29.7 sheep per hectare for five years from 1967 to 1971 at the Kybybolite Research Centre, South Australia. Autumn deferment resulted in increased liveweight and wool growth rate during the months of June to September. However, liveweights and wool production under either management were similar for the remainder of the year. Because deferred grazing did not increase liveweights during the critical autumn period, and since hand feeding requirements were similar under either management system at the higher stocking rates, it is suggested that yearly stocking rates can not be increased by autumn deferment. Apart from the drought year of 1967, the continuously grazed sheep required little or no hand feeding up to 22.2 wethers per hectare. It is unlikely that the cost of hand feeding deferred sheep up to this stocking rate would be covered by the small increase in wool production. However, this would depend on the cost of conserved fodder and price received for the wool.

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.

Analyzing growth in cell cultures. I. Calculating growth rates

1986 ◽  
Vol 64 (1) ◽  
pp. 233-237 ◽  
Author(s):  
Susan R. Singer
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Growth Rates ◽  
Rate Equations ◽  
Constant Growth Rate ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Growing Cell ◽  
Absolute Growth ◽  
Plant Tissue Cultures

Growth is the major parameter used to assess novel phenotypes derived from plant tissue cultures. Any quantitative analysis of growth must have an explicit rational basis. Frequently this criterion is not met. For example, the calculation (W2 − W1)/W1(W1 = initial weight; W2 = final weight) approximates neither linear nor exponential growth. Yet, it is a common method of analysis, as is the related calculation W2/W1. When absolute growth values provide insufficient information, meaningful relative growth rate equations can be utilized. Relative growth rates should be evaluated as ln (W2/W1)/(t2 − t1) for t = time, thereby yielding a constant growth rate for exponentially growing cell lines. Linear growth (root growth, for example) can be approximated by 2(W2 − W1)/((W1 + W2)(t2 − t1)). All methods of analysis we have encountered assume that relative growth at a given instant depends on total mass. The possibility exists that growth may actually be proportional to mass raised to some power less than one. For example, growth could be limited to a thin outer shell of a spherical callus. Then the relative growth rate would equal 3(W21/3 − W11/3)/(t2 − t1). Data can be seriously distorted when inappropriate calculations are used. Such distortions are exacerbated when comparisons are made. In all cases an adequate assessment of growth kinetics for each cell line and each treatment is essential.

Growth responses of six bryophyte species to different light intensities

1993 ◽  
Vol 71 (5) ◽  
pp. 661-665 ◽  
Author(s):  
Emmanuel Rincón
Keyword(s):  
Growth Rate ◽  
Light Intensity ◽  
Growth Rates ◽  
Growth Analysis ◽  
Total Chlorophyll ◽  
Light Conditions ◽  
Growth Responses ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Plastic Responses

The growth responses of Brachythecium rutabulum, Eurhynchium praelongum, Lophocolea bidentata, Plagiomnium undulatum, Pseudoscleropodium purum, and Thuidiurn tamariscinum, growing under seven different light conditions, were determined in a 36-day laboratory experiment. Biomass production, relative growth rate, chlorophyll content, and morphological plastic responses (bending of the shoots) were determined following initial and final harvests. All species achieved greater biomass as irradiance increased. This trend was also observed in the relative growth rates, which were higher as irradiance increased, for all the bryophytes investigated. All species except L. bidentata showed an increased elevation of the shoot as irradiance decreased. Total chlorophyll was higher in all species at the lowest irradiance level, but no clear differences were observed in the ratios of chlorophyll a to b for all the species. Key words: grassland bryophytes, light intensity, growth analysis, plasticity.

A Prediction of Entrainment Growth Rate for Debris-flow Hazard Analysis Using Multiple Regression Analysis

2015 ◽  
Vol 15 (6) ◽  
pp. 353-360 ◽  
Author(s):  
Seok Yoon ◽  
Seung-Rae Lee ◽  
Jun-Young Park ◽  
Joo-Hyun Seong ◽  
Deuk-Hwan Lee
Keyword(s):  
Growth Rate ◽  
Regression Analysis ◽  
Debris Flow ◽  
Multiple Regression Analysis ◽  
Multiple Regression ◽  
Hazard Analysis ◽  
Debris Flow Hazard

On the prediction of crystal morphology. III. Equilibrium and growth behaviour of crystal faces containing multiple connected nets

1999 ◽  
Vol 55 (1) ◽  
pp. 84-94 ◽  
Author(s):  
R. F. P. Grimbergen ◽  
P. Bennema ◽  
H. Meekes
Keyword(s):  
Growth Rate ◽  
Monte Carlo ◽  
Growth Rates ◽  
Crystal Morphology ◽  
Crystal Habit ◽  
Growth Behaviour ◽  
Equilibrium Conditions ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Surface Phases

In this paper, the equilibrium and growth behaviour of faces (hkl) with more than one connected net is studied. It is shown that for these types of orientation different surface phases exist under equilibrium conditions as a function of temperature. Depending on the exact bonding topology at the surface, flat, rough or disordered flat phases are found. Moreover, the growth rate R_{hkl} of such faces can differ significantly from the usually calculated relative growth rates based on the attachment energy. Monte Carlo simulations confirm the results from the Hartman–Perdok analyses and offer a tool for the prediction of the crystal habit as a function of supersaturation.

Stage-dependent sensitivity to ultraviolet radiation in zygotes of the brown alga Fucus serratus

Zygote ◽  
2003 ◽  
Vol 11 (2) ◽  
pp. 101-106 ◽  
Author(s):  
María Altamirano ◽  
Antonio Flores-Moya ◽  
Ralph Kuhlenkamp ◽  
Félix L. Figueroa
Keyword(s):  
Growth Rate ◽  
Uv Radiation ◽  
Growth Rates ◽  
Brown Alga ◽  
Radiation Condition ◽  
The Other ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Inhibition Of Growth ◽  
Fucus Serratus

Sensitivity to ultraviolet (UV) radiation (UV-A, λ = 315-400 nm; plus UV-B, λ = 280-315 nm) of zygotes of the brown alga Fucus serratus L. (Phaeophyta) has been assessed through effects on growth of developing germlings. Different stages of development were distinguished by considering 5 h periods of time after fertilisation. Both the stage of the zygote and the UV radiation condition significantly affected growth of developing germlings. The negative response of growth rate of early stages of the zygotes to UV radiation seemed to be caused by UV-B rather than UV-A radiation, as the lowest relative growth rates were always estimated for germlings developed from zygotes irradiated with UV-B radiation. As regards the stage of the zygote, those germlings that developed from zygotes irradiated at 5-10 h after fertilisation showed the strongest inhibition of growth compared with the other stages. These results point to polarisation as the most UV-sensitive process during the first 24 h of the development of the zygote. A non-linear relationship between the developmental stage of the zygote and the sensitivity to UV radiation is suggested.

scholarly journals GROWTH OF MANGROVE COCKLE (Anandara antiquata) CULTURED IN CAGES

2009 ◽  
Vol 34 (2) ◽  
pp. 91-96
Author(s):  
Jesaja A. Pattikawa ◽  
Elizabeth Ferdinandus
Keyword(s):  
Growth Rate ◽  
Relative Growth Rate ◽  
Growth Rates ◽  
Condition Factor ◽  
Intertidal Area ◽  
Relative Growth ◽  
Relative Growth Rates ◽  
Weight Relationship ◽  
Large Size ◽  
Length Increment

Study on growth of mangrove cockle (Anadara antiquata) was conducted in the intertidal area of Passo, Inner Ambon Bay. Three size-classes of 25 individual cockles were cultured in 1 m3 cage. Length increment data was collected every two weeks for seven periods of observation. Relative growth rate, length-weight relationship and condition factor were estimated using formula proposed by Effendie, Pauly and King, respectively. The results showed that the small size had the highest length increment and relative growth rates while the large size had the best condition factor. Length-weight relationship showed isometric growth for all categories.

Comparative production of lean meat from Friesian bulls and steers over a range of nutritional planes at pasture

1981 ◽  
Vol 21 (110) ◽  
pp. 249 ◽  
Author(s):  
FJ Mickan ◽  
GW Thomas ◽  
SA Spiker
Keyword(s):  
Growth Rate ◽  
Growth Rates ◽  
Entire Range ◽  
Meat Production ◽  
Stocking Rate ◽  
Average Growth ◽  
Lean Meat ◽  
Manufacturing Trade ◽  
Stocking Rates

The growth rate and carcase characteristics of Friesian bulls and steers were compared when the animals were fed solely on pasture from 8 to 18 months of age. The animals were set stocked at rates ranging from 3.0 to 6.0 animals ha-1, so that average growth rates of the steers ranged from 0.87 to 0.57 kg d-1. All were slaughtered at 18 months of age for the manufacturing meat trade. For each additional animal per hectare the average daily liveweight gain of both bulls and steers was reduced by 0.1 0 kg d-1. However, at all stocking rates bulls maintained a 0.06 kg d-1 advantage over the steers. These results do not support the suggestion that as the plane of nutrition increases, so does the advantage in growth rate of the bulls over that of the steers. Seasonal liveweight gains of the two sex types and the effect of stocking rate on these are discussed. For each 0.1 0 kg d-1 increase in steer liveweight gain carcase weight per animal increased by 19 kg and the bulls produced 25 kg more carcase weight than the steers. As the plane of nutrition increased, the percentage of saleable meat produced by the steers was constant (66.2%) while that of the bulls increased (68.7%-72.3%). This trend was reversed for the percentage of fat trimmed out of the carcases. The fat trim of the bulls was 3.6% while that of the steers increased from 6.4% to 8.9%. Over the entire range of nutrition levels, bulls were superior to steers in all attributes considered necessary for the manufacturing trade. However, under Australian conditions, seemingly unjustifiable penalty rates for slaughtering and, to a lesser extent, farmer prejudice, severely restrict the use of young grazing bulls for lean meat production.

Sign in / Sign up

Export Citation Format

Share Document