Secondary sexual characters, energy use, senescence, and the cost of reproduction in sockeye salmon

1999 ◽  
Vol 77 (11) ◽  
pp. 1663-1675 ◽  
Author(s):  
Andrew P Hendry ◽  
Ole K Berg
Keyword(s):  
Egg Production ◽  
Sockeye Salmon ◽  
Energy Use ◽  
Relative Size ◽  
Cost Of Reproduction ◽  
Bristol Bay ◽  
Secondary Sexual Characters ◽  
In The Wild ◽  
The Cost ◽  
Secondary Sexual

Reproductive development and energy stores were characterized for sockeye salmon (Oncorhynchus nerka) maturing in the wild (Pick Creek, Bristol Bay, Alaska). Between freshwater entry and the start of spawning, ovaries increased in mass by 87.1% and secondary sexual characters increased in linear dimension by 13.0-47.4%. Between the start of spawning and death, secondary sexual characters decreased in relative size by 3.3-12.7%. Mass-specific somatic energy declined from freshwater entry (6.7% fat, 20.6% protein, 6.6 kJ·g-1) to the start of spawning (1.6% fat, 18.0% protein, 4.5 kJ·g-1) and finally to death (0.1% fat, 14.4% protein, 2.9 kJ·g-1). Stored fat appeared to be used primarily for upriver migration and egg production, whereas stored protein appeared to be used primarily for the development of secondary sexual characters and metabolism during spawning. Most development of secondary sexual characters occurred late in maturation, perhaps to forestall deterioration of muscle tissue. Relative to populations with long freshwater migrations, Bristol Bay sockeye salmon stored less fat before entering fresh water and used less fat before death. The total energy cost of reproduction (freshwater entry until death, including gonad investment) was 74.1% for females and 66.1% for males, higher than levels typically reported for iteroparous salmonids.

Pink salmon (Oncorhynchus gorbuscha) migratory energetics: response to migratory difficulty and comparisons with sockeye salmon (Oncorhynchus nerka)

2003 ◽  
Vol 81 (12) ◽  
pp. 1986-1995 ◽  
Author(s):  
G T Crossin ◽  
S G Hinch ◽  
A P Farrell ◽  
M P Whelly ◽  
M C Healey
Keyword(s):  
Egg Production ◽  
Sockeye Salmon ◽  
Energy Use ◽  
Energy Content ◽  
Oncorhynchus Nerka ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Energetic Efficiency ◽  
Fraser River ◽  
Pink Salmon Oncorhynchus Gorbuscha

Pink salmon (Oncorhynchus gorbuscha) are generally considered weak upriver migrants relative to sockeye salmon (Oncorhynchus nerka), though this assertion is largely anecdotal. To assess energy-use patterns during migration, we collected pink salmon from two major Fraser River stocks (Weaver and Seton in British Columbia, Canada) in 1999 at three times and locations: (1) at the start of freshwater migration, (2) at the end of migration before spawning, and (3) immediately after spawning. We calculated the energy content of somatic and reproductive tissues, recorded several body measurements, and conducted both intraspecific (between pink stocks) and interspecific analyses with co-migrating Fraser River sockeye salmon collected during the same season. We found that between pink salmon stocks, there were no significant energetic or morphological differences either at river entry or upon arrival at spawning areas regardless of the level of migratory difficulty encountered. When compared with sockeye salmon, however, we found that pink salmon began upriver migration with significantly smaller somatic energy reserves but made up for this deficiency by minimizing absolute transport and activity costs, presumably by seeking out migratory paths of least resistance. This energetic efficiency comes at a cost to reproductive output: relative to sockeye salmon, pink salmon diverted less absolute energy to egg production, producing smaller ovaries and fewer eggs. We speculate that fundamental differences in behaviour shape the migratory energetic tactics employed by pink salmon.

Probiotics in the diets of laying quails

2020 ◽  
pp. 60-66
Author(s):  
O. Merzlyakova ◽  
V. Rogachyev ◽  
V. Chegodaev
Keyword(s):  
Bacillus Subtilis ◽  
Bacillus Licheniformis ◽  
Egg Production ◽  
Positive Impact ◽  
Hematological Parameters ◽  
Economic Effect ◽  
Egg Laying ◽  
Control Group ◽  
Egg Mass ◽  
The Cost

The efficiency of introducing probiotics based on strains of Bacillus subtilis, Bacillus licheniformis and their consortium in the amount of 150 g/t of feed into the diets of laying quails has been studied. The experiment lasting 182 days has been carried out on four groups of quails with 30 heads in each. The quails have been housed in the broiler battery in compliance with the required microclimate conditions. Quails of all groups have been received the main diet (compound feed) developed taking into account their age and physiological characteristics. The quails of the 1st, 2nd and 3rd experimental groups in addition to the main diet received probiotics (150 g/t compound feed) based on strains Bacillus subtilis, Bacillus licheniformis and their consortium, respectively. It has been found that feeding the laying quails of the consortium of strains Bacillus subtilis and Bacillus licheniformis had the most significant positive impact on their productive performance, it allowed to increase egg production by 7,81 %, egg laying intensity by 5,0 %, egg mass yield by 9,77 %, while reducing feed expenditures for 10 eggs by 13,35 %. The yield of hatching eggs has been increased by 7,03 %, hatchability of chickens from laid and fertilized eggs by 8,33 and 8,35 %, brooding waste decreased by 21,74 %. Hematological parameters of quails during the whole experiment were within the physiological norm. The economic effect calculated on the basis of data on the cost of compound feed, probiotics and the cost of sold eggs of quail laying was 14,56 % in the 3rd experimental group (in relation to the control group).

Cost Optimization of Net-Zero Energy House

2007 ◽  
Author(s):  
George A. Mertz ◽  
Gregory S. Raffio ◽  
Kelly Kissock
Keyword(s):  
Energy Use ◽  
Cost Optimization ◽  
Building Design ◽  
Building Energy ◽  
Zero Energy ◽  
Resource Limitations ◽  
Net Zero Energy ◽  
Net Zero ◽  
Building Energy Use ◽  
The Cost

Environmental and resource limitations provide increased motivation for design of net-zero energy or net-zero CO2 buildings. The optimum building design will have the lowest lifecycle cost. This paper describes a method of performing and comparing lifecycle costs for standard, CO2-neutral and net-zero energy buildings. Costs of source energy are calculated based on the cost of photovoltaic systems, tradable renewable certificates, CO2 credits and conventional energy. Building energy simulation is used to determine building energy use. A case study is conducted on a proposed net-zero energy house. The paper identifies the least-cost net-zero energy house, the least-cost CO2 neutral house, and the overall least-cost house. The methodology can be generalized to different climates and buildings. The method and results may be of interest to builders, developers, city planners, or organizations managing multiple buildings.

Relationships between body size and secondary sexual characters, and sperm characters in male Dolly Varden char (Salvelinus malma )

2016 ◽  
Vol 26 (3) ◽  
pp. 397-402 ◽  
Author(s):  
Toshiaki Yamamoto ◽  
Noritaka Hirohashi ◽  
Eiji Fujiwara ◽  
Tatsuya Suzuki ◽  
Hatsuna Maruta ◽  
...  
Keyword(s):  
Body Size ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Dolly Varden Char ◽  
Secondary Sexual Characters ◽  
Sperm Characters ◽  
Secondary Sexual

Differentiation of the sexual characters and onset of maturity in the males of the "red claw" crayfish, Cherax quadricarinatus (Von Martens, 1898) (Astacidea, Astacida, Parastacidae)

2010 ◽  
Vol 60 (2) ◽  
pp. 195-208 ◽  
Author(s):  
Laura Susana López Greco ◽  
Fernanda Jimena Vazquez
Keyword(s):  
Sexual Maturity ◽  
Vas Deferens ◽  
Developmental Stages ◽  
Stage I ◽  
Early Event ◽  
Cherax Quadricarinatus ◽  
Secondary Sexual Characters ◽  
Single Structure ◽  
Red Claw Crayfish ◽  
Secondary Sexual

AbstractThe differentiation of the male reproductive system, the copulatory structures, "red patch" and onset of sexual maturity were studied in Cherax quadricarinatus. For this characterization 353 males were observed, dissected and processed for histological analysis. Three developmental stages were identified. At stage I the testes are two parallel cords with a few lobes or acinii, connected medially by a short thin bridge (X-shape) and the vasa deferentia are straight transparent cords. In the second stage, more lobulated testes present an H-shape and the vas deferens begins to differentiate into three distinct regions: proximal, medial and distal. In the last stage testes are two parallel cords tending to fuse along their entire length and become a single structure. From this stage, the development of the "red patch" occurs and spermatophore formation is observed in the vas deferens giving it white colour. These primary and secondary sexual characters could indicate the onset of sexual maturity. The morphology of the copulatory structure is lobular at stage I and it differentiates into an elongated structure during stage II. This study shows that in C. quadricarinatus the differentiation of primary and secondary sexual characters of males starts simultaneously and very early in development (0.09-0.10g achieved nearly 1 month old) and that acquisition of sexual maturity is also an early event (6g achieved nearly 3 month old). The compared features within Astacidea and Decapoda and the possible applications in the analysis of phylogenetic relationships between different taxa are discussed.

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