The Biology of an Ampeliscid Amphipod Crustacean Sibling Species Pair

1967 ◽  
Vol 24 (2) ◽  
pp. 305-355 ◽  
Author(s):  
Eric L. Mills
Keyword(s):  
Sibling Species ◽  
Egg Production ◽  
Somatic Growth ◽  
Fine Sand ◽  
Morphological Adaptations ◽  
Feeding Type ◽  
Gonad Growth ◽  
Egg Number ◽  
Gill Area ◽  
Amphipod Crustacean

The amphipod sibling species Ampelisca vadorum and A. abdita have an overwintering generation and a summer generation. Breeding begins above 8 C. In A. abdita, breeding is probably correlated with the full moon. Curves of growth in length are linear, except where growth slows in winter. Length–weight curves are exponential, and A. vadorum is slightly heavier than A. abdita at any given length. The slope of the length–weight curves is the same in both species. Growth in weight is not isometric; weight increases less rapidly than does length. In some allometric features the two species stop growth at different points on the same line, but other morphological features develop out of phase due to genetic differences in patterns of development. The two species differ in a number of biological features including egg size, metabolic contribution in egg production, relative gill area, and probably egg number. Reported "intersexes" are actually subadult males. The sex ratio in both species is always 1:1. Gonad growth and somatic growth have different temperature limits.Tubes, tube building, and feeding are described. Three major functional groups of ampeliscids show marked morphological adaptations to feeding type and sediment. Free swimming occurs at times of breeding, ensuring fertilization of eggs and dispersal of young to new and favourable environments.Ampelisca vadorum occurs on course sand, A. abdita on fine sand to mud. Range, temperature, and depth preferences of these and other North American Ampelisca species are outlined. The fauna associated with A. vadorum and A. abdita is described. The unique microtopography of Ampelisca areas affects the nature of the association. Ampelisca abdita is successful in a crowded environment because it grows fast and breeds early. Ecological, life history, and taxonomic evidence all indicate that A. vadorum and A. abdita are sibling species.

scholarly journals SAPU-SAPU FISH (Hyposarcus pardalis) AS A SINGLE PROTEIN SOURCE FOR LAYING MOJOSARI DUCKS

2016 ◽  
Vol 41 (3) ◽  
pp. 117-124 ◽  
Author(s):  
B. Indarsih ◽  
A. Asnawi ◽  
D. K. Purnamasari
Keyword(s):  
Body Weight ◽  
Feed Intake ◽  
Egg Production ◽  
Egg Quality ◽  
Production Performance ◽  
Protein Source ◽  
Egg Mass ◽  
Final Body Weight ◽  
Egg Number ◽  
Single Protein

The present study was conducted to evaluate the optimum level of dietary inclusion and the form of feeding sapu-sapu fish (SSF) as a single protein source for feed components of small holder Mojosari duck farming. A total of 180 twenty four wk-old laying ducks were fed with two forms (sun-dried and ground-fresh) and three levels of SSF (10, 20 and 30%) from 24 to 32 wk of age. Experimental diets were formulated containing 105.1; 141.5 and 177.9 g/kg crude protein and 3078; 3065 and 3052 kcal metabolizable energy (ME) /kg diet. Production performance and egg quality were measured. The form of SSF had a significant effect (P<0.0001) on feed intake, egg production, feed conversion, egg mass and egg number except final body weight. No significant effects (P>0.05) were found on all of the performance parameters measured due to feeding levels of SSF except feed intake and final body weight. The interaction of form and feeding level was significant (P<0.05) on egg and body weights. Low performance and egg quality were observed in the birds fed a diet containing the dried SSF. It can be suggested that local ducks required 20% SSF as a single protein source for maximum egg production (41.2%) and total egg number per wk (3.1 eggs/bird/wk) during 8 wk of rearing period. Egg quality can be improved by feeding the fresh SSF. However, due to be sufficiently better processing technique, the dried SSF would be potential to replace the common fish for laying ducks.

Timing and Magnitude of Energy Deposition and Loss in the Body, Liver, and Gonads of Northern Pike (Esox lucius)

1979 ◽  
Vol 36 (5) ◽  
pp. 481-487 ◽  
Author(s):  
James S. Diana ◽  
W. C. Mackay
Keyword(s):  
Somatic Growth ◽  
Northern Pike ◽  
Esox Lucius ◽  
The Body ◽  
Total Production ◽  
Spawning Period ◽  
Pike Esox Lucius ◽  
Testicular Growth ◽  
Gonad Growth ◽  
Somatic Energy

Northern pike (Esox lucius) were sampled periodically from Lac Ste. Anne, Alberta, between March 1976 and September 1978. The yearly cycle of production and depletion was determined for individual 3-yr-old fish. Body growth in length was similar for both sexes, and occurred during the summer. Somatic caloric growth was completed during the summer by females, while male somatic growth continued over winter. Gonad growth began in August; testicular growth was completed by September while ovarian growth occurred mainly during winter. There was no loss of somatic energy during ovary growth. Energy requirements for testicular growth appeared to come from liver stores. Both sexes lost considerable somatic energy between March and May, the spawning period; this loss appeared to be due to spawning activity and not late gonad growth. Young-of-year fish did not mature sexually and all of their energy accumulation went into somatic tissue. Total production in females from May to March was twice as high as production in males. Both sexes had similar yearly somatic production, while females had approximately 15 fold higher gonadal production than males. Key words: calories, growth, liver, gonad, somatic, Esox lucius, production, spawning depletion

Genetic parameters for egg weight v. age curve, and other egg production and egg weight traits, in synthetic lines of chickens

1983 ◽  
Vol 34 (1) ◽  
pp. 85 ◽  
Author(s):  
BH Yoo ◽  
BL Sheldon ◽  
RN Podger
Keyword(s):  
Standard Deviation ◽  
Genetic Correlation ◽  
Egg Production ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Egg Mass ◽  
Control Line ◽  
Egg Weight ◽  
Egg Number ◽  
Selection For

An exponential curve, W = P-Qexp(- Rt), where W is egg weight at age t, was fitted to egg weights of individual pullets, and genetic parameters were estimated for P, Q and R, the residual standard deviation and other egg weight and egg production characters. The data consisted of records collected over six generations on more than 4000 pullets in two selection lines and a control line which originated from a synthetic gene pool of White Leghorn x Australorp crosses. The half-sib and offspring-on-parent regression estimates of heritability pooled over the lines were 0.23 and 0.33 for P, 0.14 and 0.20 for Q, and 0.14 and 0.25 for R. Genetic correlations were estimated to be -0.10 between P and Q, -0.46 between P and R, and 0.90 between Q and R. These estimates suggest that the egg weight v. age curve may be modified to increase the proportion of eggs in desirable weight grades and reduce the incidence of oversized eggs later in the production year. The genetic correlation between mean weight of first 10 eggs and egg weight at 62 weeks of age was estimated to be 0.68, further suggesting that early egg weight may be improved partly independently of late egg weight. The heritability estimates of egg mass output were not higher than those of egg number in spite of the highly heritable average egg weight being an important component of egg mass, probably because of the negative genetic correlation (r = -0.49) between egg number and average egg weight. The standard deviation of individual pullet's egg weights was moderately heritable and genetically correlated positively with egg weight characters and negatively with egg production; these estimates were consistent with the responses to selection for reduced egg weight variability observed elsewhere

Intraspecific variation in reproductive effort by female Parapediasia teterrella (Lepidoptera: Pyralidae) and its relation to body size

1990 ◽  
Vol 68 (1) ◽  
pp. 44-48 ◽  
Author(s):  
Larry D. Marshall
Keyword(s):  
Life History ◽  
Body Size ◽  
Egg Production ◽  
Egg Size ◽  
Reproductive Effort ◽  
Life History Evolution ◽  
Reproductive Parameters ◽  
Trade Offs ◽  
Egg Number ◽  
Lepidoptera Pyralidae

Daily egg production of the moth Parapediasia teterrella declined over the life-span of the female but egg size remained constant. The absence of water resulted in lower fecundity and early mortality. Egg size and lifetime fecundity showed considerable inter-individual variation and large females produced more and larger eggs than their smaller counterparts. Large females expended greater reproductive effort than small females. Hatching success was negatively related to egg size. In spite of this, large females laying large eggs had higher fitness than small females. I postulate that multiple reproductive strategies within a species, resulting from differences in reproductive effort expended, may explain why expected trade-offs in reproductive parameters (e.g., egg size versus egg number) were not found in this species. Furthermore, I argue that the prevalent interpretation of life-history evolution (that body size is the important determining parameter of life-history parameters) may reflect correlation of body size with reproductive effort, and reproductive effort may be more important in determining the nature of trade-offs between reproductive parameters.

The reproductive effort of Lepeophtheirus pectoralis (Copepoda: Caligidae): insights into the egg production strategy of parasitic copepods

Parasitology ◽  
2015 ◽  
Vol 143 (1) ◽  
pp. 87-96 ◽  
Author(s):  
D. G. FRADE ◽  
M. J. SANTOS ◽  
F. I. CAVALEIRO
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Reproductive Effort ◽  
Parasitic Copepods ◽  
Egg Number ◽  
Production Strategy ◽  
European Flounder ◽  
Fish Hosts ◽  
First Time ◽  
The Relationship

SUMMARYThe reproductive effort of Lepeophtheirus pectoralis (Müller O. F., 1776), a caligid copepod, which is commonly found infecting the European flounder, Platichthys flesus (Linnaeus, 1758), is studied in detail for the first time. Seasonal variation in body dimensions and reproductive effort are analysed. Data for 120 ovigerous females, 30 from each season of the year, were considered in the analyses. Females were larger and produced a larger number of smaller eggs in winter, than during the summer. The relationship between egg number and egg size is similar to that recorded for other copepods exploiting fish hosts. Much of the recorded variation was also similar to that reported for a copepod parasitic on an invertebrate host, which suggests the possibility of a general trend in copepod reproduction. Overall, our results provide further support for the hypothesis that there is an alternation of summer and winter generations.

Estimation of genetic parameters of growth and egg production traits by animal model in IWK layer strain

2019 ◽  
Author(s):  
P. Chandan ◽  
T.K. Bhattacharya ◽  
U. Rajkumar ◽  
L.L.L. Prince ◽  
R.N. Chatterjee
Keyword(s):  
Animal Model ◽  
Body Weight ◽  
Egg Production ◽  
Heritability Estimate ◽  
The Body ◽  
Production Traits ◽  
Economic Traits ◽  
Egg Weight ◽  
Egg Number ◽  
Highly Correlated

Indian White Leghorn strain-IWK has been improved for higher egg weight as well as number over last twelve generations at ICAR-Directorate of Poultry Research, Hyderabad. The data collected on various economic traits of egg production were analyzed using REML approach of animal model. Current study showed that the heritability estimate of body weight, age at sexual maturity (ASM), egg numbers and egg weight was moderate to high, low to moderate, low and high, respectively. The body weight was positively correlated with egg weight but negatively correlated with egg numbers. The body weight at 16 and 20 weeks were negatively correlated with ASM and were very important for achieving early ASM. ASM was negatively correlated with egg numbers. The egg weight regressed as the egg number increased. The part period egg production EP52 was highly correlated with EP64; therefore EP52 can be used for selecting parents for higher egg number instead of EP64.

A comparison of the efficiency of food utilization for egg production of some inbred lines of Brown Leghorn fowls

1960 ◽  
Vol 55 (2) ◽  
pp. 241-245 ◽  
Author(s):  
W. Bolton
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Analytical Data ◽  
Inbred Lines ◽  
Standard Errors ◽  
Food Utilization ◽  
Food Conversion ◽  
Egg Weight ◽  
Egg Number

1. The efficiency of food conversion of Brown Leghorn fowls inbred for egg number, or egg size, or egg number and egg size have been compared.2. Comparison between the lines was made for egg numbers, total egg weight and total egg energy. Egg energy was the best measure of production, total egg weight was the next best and egg number the poorest.3. When allowance was made for differences in rates of egg production and egg size, there were no differences in the efficiency of conversion of food to eggs between the lines.4. The standard errors of the means for the analytical data on the twelve replicate mixes of the diet were relatively small, but the range in values was appreciable. The importance of analysing diets in nutrition experiments is stressed, particularly for ‘iso-caloric’ diets.

Embryonic Development and Energetic Investment in Egg Production in Relation to Size of Female Lobster (Homarus americanus)

1987 ◽  
Vol 44 (6) ◽  
pp. 1157-1164 ◽  
Author(s):  
Jean Attard ◽  
Christiane Hudon
Keyword(s):  
Embryonic Development ◽  
Egg Production ◽  
Energy Content ◽  
Larval Growth ◽  
Somatic Growth ◽  
Dry Weight ◽  
Homarus Americanus ◽  
Female Size ◽  
Growth And Survival ◽  
The Difference

The egg development index, dry weight, and energy content were measured on eggs from 148 ovigerous female lobsters (Homarus americanus) caught off îles de la Madeleine (Québec). Two modes of embryonic development were observed at stages 3 and 8 (Perkins. 1972. Fish. Bull. 70: 95–99). Stage 3 predominated among females of 71–82 mm and stage 8 among those of 83–110 mm carapace length (CL), indicating that larger females both extrude and hatch their eggs earlier than smaller females. Energy content per egg increased with female size and ranged from 4.6 cal∙egg−1 for females 72–76 mm CL to 5.2 cal∙egg−1 for females 107–110 mm CL. Females between 82 and 90 mm CL invested 0.155 kcal per gram of their own weight in egg production, which was the maximum value in the size range. Females smaller than 82 mm CL and larger than 90 mm CL expended proportionately less on egg production, with the difference allocated to either somatic growth in the smaller or maintenance in the larger animals. Large females produce proportionately more eggs, containing more calories per egg which hatch at an earlier time than small females. The higher energy content of eggs from large females and their earlier hatching are probably factors that enhance larval growth and survival. If so, large females contribute relatively more to recruitment than their greater fecundity.

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