The Food and the Food Supply of Sockeye Salmon (Oncorhynchus nerka Walbaum) in Cultus lake, British Columbia.

1937 ◽  
Vol 3 (5) ◽  
pp. 450-468 ◽  
Author(s):  
William E. Ricker
Keyword(s):  
Low Temperature ◽  
Intraspecific Competition ◽  
Sockeye Salmon ◽  
Abundant Species ◽  
Minor Importance ◽  
Important Food ◽  
Total Food ◽  
Competition For Food ◽  
Summer Feeding ◽  
Food Consumed

The analysis of several hundred stomachs of sockeye salmon taken from Cultus lake at all seasons shows that pelagic plankton crustaceans are practically the only food of the fingerlings, and are the most important food of the older fish. The total food consumed by fingerlings, per unit bulk, is greatest in July and August, least in winter. The entomostracan food available in the lake, as determined from plankton samples, varies seasonally in a similar manner. The percentage utilization of each of the four species of Entomostraca by a fingerling sockeye population is related directly to the plankter's abundance, and inversely to its size. Individual sockeye, however, occasionally exhibit preference for smaller or less abundant species. The summer feeding of fingerlings appears to be chiefly confined to the region between 5 and 15 metres depth, which includes the thermocline and adjacent narrow strips of the epilimnion and hypolimnion. Foraging is limited upward by scarcity of food, and downward by poor illumination or low temperature. Other fish in the lake are known to compete with sockeye for plankton, but such interspecific competition is believed to be quantitatively of minor importance, in summer at least. Intraspecific competition for food in years of large sockeye populations is sufficient to reduce their rate of growth, and is probably responsible for an unusually early decline, in those years, of the summer's supply of Entomostraca.

The Job Of Microfinance For The Advancement Of Self Help Groups In India

2019 ◽  
Vol 118 (8) ◽  
pp. 236-240
Author(s):  
Dr.R. Murugesan ◽  
M. Leelavathi ◽  
Dr. K. Ravindran
Keyword(s):  
High Growth ◽  
High Growth Rate ◽  
Entrepreneurial Skills ◽  
Self Help ◽  
The Poor ◽  
Total Food ◽  
Self Help Groups ◽  
Positive Step ◽  
Food Consumed

towards jumping from the category of developing economy to developed economy there is one big factor that stops and poses a hindrance in its path of advancement and that obstacle is termed as Poverty. The Indian economic policy focuses on a high growth rate along with a equal participation of the poor so that they avail the opportunities available in the market economy. And in order to ensure the participation of the poor it has become important for the country to create a platform where the poor can easily access the various financial products. Microfinance is one such strategy for inclusive growth. Microfinance can change the life of the poor though not completely but a reasonable change can be ensured. In different phases of life women play a crucial role despite the discrimination that is faced by them. But equality can be endowed to women by enhancing the entrepreneurial skills in them. This is possible through Self Help Groups (SHGs). In India women produce around 30% of the total food consumed but she gets only 10% of the property or wealth of the country. Development of women is inevitable for the development and growth of any economy. SHGs happen to be a positive step in this direction. Along with these mediums there should be a cheap and easy source of credit for them and Microfinance fulfills the requirement. This study aims to find the role of this strong medium of Microfinance in the advancement of SHGs in India

Efficiency of lean meat production by British Friesian and Jersey steers

1978 ◽  
Vol 27 (2) ◽  
pp. 181-189 ◽  
Author(s):  
E. Hind
Keyword(s):  
Live Weight ◽  
Maximum Efficiency ◽  
Meat Production ◽  
Allometric Relationship ◽  
Lean Tissue ◽  
Anatomical Basis ◽  
Total Food ◽  
Complete Diet ◽  
Equal Maximum ◽  
Food Consumed

ABSTRACT1. Eight-one British Friesian and 44 Jersey steers was slaughtered at 1. 12, 24, 48 or 72 weeks of age. Those aged 24 weeks and over were reared on a standard complete diet offered ad libitum, and individual food intakes were recorded until slaughter when carcasses were dissected on an anatomical basis.2. From 1 to 72 weeks British Friesians were on average 50% heavier than Jerseys and consumed 47% more food. Total lean tissue (L) increased 11-fold to 137 + 6·4 kg in the British Friesians and 16-fold to 84 ± 4·7 kg in the Jersey. L as a percentage of live weight rose to 32% ±0·6 in the British Friesians and to 29% ±0·8 in the Jerseys. Breeds did not differ significantly in average efficiency of growth of lean tissue in any period.3. From 24 to 72 weeks, an allometric relationship held between L and total food consumed postnatally, F. The two breeds had the same allometric coefficient of 0·61. Current efficiency, 0·61 L/F, was thus proportional to cumulated efficiency, L/F. Allowance was made for the prenatal input, Fo, required to produce the newborn calf. An optimum slaughter point at which overall efficiency, L/(F+F0), reached a maximum occurred in each breed when postnatal input was 58% higher than prenatal input (F = 1·58F0). When the breeds had equal maximum efficiency the British Friesian: Jersey ratios for prenatal input, total food consumed and total lean produced were all 2·6:1.

scholarly journals Factors influencing the diets of four morphologically divergent fish species in nearshore marine waters

2004 ◽  
Vol 84 (4) ◽  
pp. 805-817 ◽  
Author(s):  
M. Hourston ◽  
M.E. Platell ◽  
F.J. Valesini ◽  
I.C. Potter
Keyword(s):  
Water Column ◽  
Fish Species ◽  
West Coast ◽  
Substrate Surface ◽  
Abundant Species ◽  
Calanoid Copepods ◽  
Cryptic Coloration ◽  
Small Crustacean ◽  
Competition For Food ◽  
Small Mouth

The dietary compositions of Atherinomorus ogilbyi (Atherinidae), Sillago schomburgkii (Sillaginidae), Lesueurina platycephala (Leptoscopidae) and Ammotretis elongatus (Pleuronectidae) in three nearshore habitats on the lower west coast of Australia, which varied in their exposure to wave energy and the extent to which they contain sea grass, have been determined. The dietary compositions of these four abundant teleosts differed, reflecting marked differences between the location in the water column, head and mouth morphology and feeding behaviour of these species. Atherinomorus ogilbyi, which has a relatively high and large mouth, fed mainly on planktonic invertebrates in the water column, while S. schomburgkii ingested predominantly benthic prey, such as polychaetes and bivalves, which it extracted from the sediment using its downward-protruding mouth. Lesueurina platycephala employed its large mouth, cryptic coloration and ambush feeding to target relatively large teleosts and invertebrates, while the small mouth and flattened body of Ammotretis elongatus facilitated the ingestion of small crustacean prey, e.g. cumaceans and amphipods, which live on the substrate surface. Atherinomorus ogilbyi consumed predominantly calanoid copepods, cladocerans and insects during the day and mainly amphipods at night, when the latter taxon became abundant in the water column. The dietary composition of each species underwent a similar pattern of size-related change, being most pronounced in L. platycephala during the day. The diets of A. ogilbyi and S. schomburgkii, the two species for which the data were most comprehensive, differed among habitats and seasons, reflecting differences in the densities of their main prey. Comparisons between the day-time diets of the above four species with those recorded previously for a further four abundant species in the same habitats during the day, show that food resources are well distributed among the main fish species in nearshore waters along the lower west coast of Australia. This feature, together with the size-related changes in the diets of the different species, reduces the potential for inter- and intraspecific competition for food by fish species in this environment.

The Resistance of Cultured Young Chum and Sockeye Salmon to Temperatures Below 0 °C.

1958 ◽  
Vol 15 (5) ◽  
pp. 805-813 ◽  
Author(s):  
J. R. Brett ◽  
D. F. Alderdice
Keyword(s):  
Low Temperature ◽  
Sockeye Salmon ◽  
Aqueous Humour ◽  
Pacific Salmon ◽  
Temperature Tolerance ◽  
Hudson Bay ◽  
Lethal Temperature ◽  
Low Temperature Tolerance

Recent efforts to establish Pacific salmon in Hudson Bay posed the question of low temperature tolerance in these species. A series of lethal temperature tests at −0.5, −1.0 and −1.5 °C. demonstrated that resistance to temperatures slightly below 0 °C. was limited. Freezing of the blood and aqueous humour occurred at temperatures of −1.0 and −1.5 °C.

Rates of Food Exploitation by Littoral Fishes in a Mesotrophic North-Temperate Lake

1985 ◽  
Vol 42 (3) ◽  
pp. 556-566 ◽  
Author(s):  
D. Boisclair ◽  
W. C. Leggett
Keyword(s):  
Littoral Zone ◽  
Geometric Mean ◽  
Dry Weight ◽  
Benthic Invertebrate ◽  
Trophic Levels ◽  
Total Biomass ◽  
Temperate Lakes ◽  
Total Food ◽  
North Temperate Lakes ◽  
Food Consumed

The relationship between the biomass of food consumed by the littoral zone fish community of Lake Memphremagog, Quebec, and the total biomass of littoral zone food present was estimated on a daily and annual basis. The dominant food consumed were benthic invertebrates followed by forage fishes and plankton. The daily geometric mean exploitation rate was 0.55% of the total dry weight food biomass in the littoral zone. The corresponding annual rate was 72%. Energy equivalents were 0.81% (daily) and 105% (annual). When benthic invertebrate biomass values were adjusted to more accurately reflect availability (on the basis of depth distribution in the sediments and size) the geometric mean dry weight exploitation rates were 0.80% (daily) and 104% (annual). Corresponding energy rates were 1.15% (daily) and 150% (annual). These rates are significantly lower than reported benthic P/B ratios for 21 north-temperate lakes. These data indicate that littoral zone fishes crop only a very small fraction of the food biomass in the littoral zone. We conclude that the behaviors of both predator and prey act to limit the available fraction of the total food biomass and predict that the ratio of available to total food biomass in the littoral zone of north-temperate lakes will approximate 1%. This is consistent with existing empirical models linking fish production/biomass with biomass at lower trophic levels.

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