Energy requirements and survival in embryo mottled sculpin (Cottus bairdi)

1986 ◽  
Vol 64 (5) ◽  
pp. 1104-1109 ◽  
Author(s):  
M. F. Docker ◽  
T. E. Medland ◽  
F. W. H. Beamish

Eggs of mottled sculpin, Cottus bairdi, from different parents varied in quantity and quality. Egg weight and number were positively correlated and increased with age and length of the maternal fish. Variation in egg quality included significant differences in water and energy content. Rate of development, metabolic rate, yolk conversion efficiency, and relative survival also varied among clutches. The variations in egg weight and initial water content were not significant to embryo survival. Clutch survival from fertilization to exogenous feeding was directly related to the initial energy concentration of the egg and inversely related to metabolic rate. Metabolic rate and survival were inversely and directly related, respectively, to the efficiency with which yolk was converted to tissue.

Author(s):  
W.R. Jones ◽  
S. Coombs ◽  
J. Janssen

The lateral line system of the mottled sculpin, like that of most bony fish, has both canal (CNM) and superficial (SNM) sensory end organs, neuromasts, which are distributed on the head and trunk in discrete, readily identifiable groupings (Fig. 1). CNM and SNM differ grossly in location and in overall size and shape. The former are located in subdermal canals and are larger and asymmetric in shape, The latter are located directly on the surface of the skin and are much smaller and more symmetrical It has been suggested that the two may differ at a more fundamental level in such functionally related parameters as extent of myelination of innervating fibers and the absence of efferent innervation in SNM. The present study addresses the validity of these last two features as distinguishing criteria by examining the structure of those SNM populations indicated in Fig. 1 at both the light and electron microscopic levels.All of the populations of SNM examined conform in general to previously published descriptions, consisting of a neuroepithelium composed of sensory hair cells, support cells and mantle cells, Several significant differences from these accounts have, however, emerged. Firstly, the structural composition of the innervating fibers is heterogeneous with respect to the extent of myelination. All SNM groups, with the possible exception of the TRrs and CFLs, possess both myelinated and unmyelinated fibers within the neuroepithelium proper (Fig. 2), just as do CNM. The extent of myelina- tion is quite variable, with some fibers sheath terminating just before crossing the neuroepithelial basal lamina, some just after and a few retaining their myelination all the way to the base of the hair cells in the upper third of the neuroepithelium. Secondly, all SNMs possess fibers that may, on the basis of ultrastructural criteria, be identified as efferent. Such fibers contained numerous cytoplasmic vesicles, both clear and with dense cores. In regions where such fibers closely apposed hair cells, subsynaptic cisternae were observed in the hair cell (Fig. 3).


Animals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 912
Author(s):  
Swapnil Gorakh Waghmare ◽  
Azadeh Mohagheghi Samarin ◽  
Roman Franěk ◽  
Martin Pšenička ◽  
Tomáš Policar ◽  
...  

Fish egg quality can be markedly influenced by the oocyte age after ovulation. In this study, we examined the duration of oocyte ageing in the zebrafish (Danio rerio) and whether prolonged ageing is associated with the incidence of ploidy anomalies in the resulting embryos. Oocytes were incubated in vitro for 6 h post-stripping (HPS) at 26 °C and fertilized at 2-h intervals. Meanwhile, for eggs fertilized immediately after stripping, the fertilization, embryo survival, and hatching rates started at ~80%; these rates decreased to 39%, 24%, and 16%, respectively, for oocytes that had been stored for 4 h (p ˂ 0.05), and there was an almost complete loss of egg viability at 6 HPS. Furthermore, almost 90% of the embryos derived from 6-h aged oocytes died prior to hatching, and all larvae originating from 4- and 6-h aged oocytes showed malformations. The proportion of ploidy abnormal embryos was significantly greater at 4 HPS (18.5%) than at either 0 or 2 HPS (4.7% and 8.8%, respectively). The results revealed that zebrafish oocytes retained their fertilization potential for up to 2 h after stripping at 26 °C and indicated the contribution of post-ovulatory oocyte ageing in the occurrence of ploidy anomalies in the resulting embryos.


2012 ◽  
Vol 24 (6) ◽  
pp. 843 ◽  
Author(s):  
Daniel Żarski ◽  
Sławomir Krejszeff ◽  
Katarzyna Palińska ◽  
Katarzyna Targońska ◽  
Krzysztof Kupren ◽  
...  

The aim of this study was to investigate the process of the cortical reaction in eggs of pikeperch, Sander lucioperca (L.), as well as the application of microscopic assessment of this process in egg quality evaluation. The analysis was carried out with eggs obtained from 10 females by artificial reproduction, in which hormonal stimulation with hCG was applied. Subsequently, each sample of eggs (separately from each female fish) was analysed. The analysis included observation of the cortical reaction and the process of egg swelling, and determination of the effect of temperature (12, 14 and 16°C) and the presence of spermatozoa on the cortical reaction. The results indicate that the cortical reaction in pikeperch eggs is quite violent, resulting in visible deformation of eggs between 3 and 5 min after activation. No effect of temperature or the presence of spermatozoa on the cortical reaction was observed. A strong correlation was recorded for the percentage of egg deformations observed and embryo survival rate. The described method of determination of pikeperch egg quality (based on egg deformation rate between 3 and 5 min after activation) may be highly useful, both in scientific research (where high-quality eggs are required) and in hatchery practice.


2017 ◽  
Vol 39 (3) ◽  
pp. 273
Author(s):  
André Ferreira Silva ◽  
Frank George Guimarães Cruz ◽  
João Paulo Ferreira Rufino ◽  
Waldo Mateus Plácido Miller ◽  
Nathália Siqueira Flor ◽  
...  

 This study aimed to evaluate the increasing levels (0, 1, 2, 3 e 4%) of fish by-product meal in diets for laying hens on performance, egg quality and economic analysis. A total of 160 Dekalb White hens with 52-wk old were distributed in a completely randomized design with five treatments and four replicates of eight birds each. The experiment lasted 84 days divided into four periods of 21 days. Estimates of fish by-product meal levels were determined by polynomial regression. Differences (p < 0.05) were detected for all variables of performance, in egg weight, yolk and albumen percentage, yolk and albumen height, feed cost and production cost, in which the inclusion of fish by-product meal in the diets showed better results. It can be concluded that fish by-product meal can be used in diets for hens as alternative feed, with better results in egg production, feed conversion, egg weight, yolk-albumen ratio and a reduction in feed cost and production cost. 


1981 ◽  
Vol 61 (1) ◽  
pp. 91-96 ◽  
Author(s):  
ESSI EVANS

Data were accumulated from published sources and were combined in order to estimate the effects of level of feed intake, dietary energy concentration, energy intake level and dietary forage percentage on rumen liquid turnover rates in sheep and cattle. The effects of the dietary parameters on liquid turnover rates were estimated by regression analysis, where all possible combinations of independent variables were considered. It was found that rumen liquid turnover rates increased (P < 0.05) as feed intake increased with both sheep (r = 0.610) and cattle (r = 0.715). From multiple regression analyses it was learned that the inclusion of independent variables that were related to the physical composition of the diet along with variables for intake improved the estimation of liquid turnover rates, although the independent variable related to ration composition differed between sheep and cattle. With data from sheep experiments, elevations in the digestible energy content of the diet depressed (P < 0.05) liquid turnover rate. Based upon data from cattle, decreases in the forage portion of the diet had a similar depressing (P < 0.05) effect.


1996 ◽  
Vol 39 (2) ◽  
Author(s):  
R. Carniel ◽  
F. Iacop

In this work we investigate the characteristics of the seismicity at Stromboli volcano during more than two years, i.e. from 11 May 1992 to 21 August 1994. The three paroxysmal phases of 1993 mark significant changes in the Strombolian activity; nevertheless, these are not the only ones observed. In fact, the energy content, both in terms of volcanic tremor and of number of events drops to very low values after the periods of intense activity, accompanied by a change in the spectral content of the tremor. However, equally abrupt changes in the frequency content, not accompanied by evident intensity variations, can be observed some weeks after the end of the crises. The volcano seems therefore to behave like a dynamical system with many «quite stable » states with abrupt transitions between them. An interesting observation is the appearance of an energy concentration in the spectral sectors below 3 Hz before more violent eruptive episodes; although the duration of such a phenomenon is variable, it has to be investigated as a possible precursor of potentially dangerous activity of the volcano. A continuous monitoring of the spectral content of volcanic tremor on Stromboli is confirmed to be an essential tool in order to understand the behaviour of Stromboli volcano and to try to forecast its paroxysmal phases.


2021 ◽  
Vol 51 (4) ◽  
pp. 469-476
Author(s):  
X.J. Yi ◽  
A. Rehman ◽  
R.W. Akhtar ◽  
A. Abbas ◽  
K. Hussain ◽  
...  

This study was conducted to appraise the effects on egg quality and production performance of laying hens when drinking water was supplemented with calcium (Ca) and magnesium (Mg). A total of 384 (64-week-old) Hy-line Brown laying hens were assigned at random to four treatments, which consisted of CON: unsupplemented drinking water; T1: drinking water + 2 mg/L Ca + 250 mg/L Mg; T2: drinking water + 4 mg/L Ca + 510 mg/L Mg /10 L; and T3: drinking water + 5 mg/L Ca and 760 mg/L Mg. The experiment lasted six weeks. Water intake increased linearly in week 1 with the rising levels of Ca and Mg in the drinking water. Increasing the Ca and Mg levels improved eggshell strength (week 2 (P =0.01), week 5 (P =0.01), and week 6 (P = 0.03), and eggshell thickness (week 6) (P =0.02) and reduced the rate at which eggs were broken (week 4) (P =0.01). The supplemental Ca and Mg did not affect egg production, egg weight, Haugh unit, albumen height, eggshell colour, and yolk colour compared with CON. Nor did they influence the Haugh unit and albumen height after storing for 1, 5, 10 and 15 days. In conclusion, adding Ca and Mg to the drinking water increased the thickness and strength of the eggshells.


1980 ◽  
Vol 28 (1) ◽  
pp. 29-35
Author(s):  
A.R. El Boushy ◽  
L.G.M. van Gils ◽  
M.C. Papadopoulos

Twenty groups of 36 laying hens in individual cages were fed on one of 5 diets in which the energy:protein ratio was constant. Diets 1 to 5 had crude protein 12.0, 12.9, 14.0, 15.0 and 16.0% and metabolizable energy 8.71, 9.57, 10.27, 11.10 and 11.70 MJ/kg. From 24 to 64 weeks old, egg production of hens given diets 1 to 5 was 71.46, 71.31, 72.51, 71.13 and 69.99%, respectively. Corresponding values of mean egg weight, weekly feed intake and efficiency of feed conversion were 60.51, 60.47, 61.11, 61.02, 61.07 g; 157.16, 147.56, 142.03, 130.37, 126.72 g; 3.674, 3.460, 3.262, 3.031, 3.014 kg feed/kg egg, respectively. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2011 ◽  
Vol 27 (4) ◽  
pp. 1649-1658 ◽  
Author(s):  
D. Kocevski ◽  
N. Nikolova ◽  
A. Kuzelov

The experiment was conducted to evaluate the influence of strain and age on some egg quality parameters (egg weight and egg shell strength) of commercial laying hens. Layers of lines ISA Brown and DeKalb White were examined in period of nine months. Both lines were at same age (28 weeks) and were confined in common facility in battery cages. Laying hens were reared and fed according to standard breeding technology. Once a month 25 eggs of each line were taken to be examined for eggshell strength and egg weight, or in other words, total 450 table eggs were tested. Analises were done in Laboratory for testing egg quality by gaudges Egg Multi Tester EMT 5200 and Egg shell Gauge (Robotmation Co. Ltd., Tokyo, Japan) which have computerised equipment to examine quality and physical characteristics of eggs. Statistic analyses on results were done by computer sub-programme ANOVA and Fisher's LSD test to determine the level of statistical significant difference between examined factors. Egg weight was under significant impact of age (P ? 0,05), but not under the influence of strain, although eggs of ISA Brown line were insignificantly heavier than eggs of DeKalb White line. Eggs were heaviest at layers with older age, while they were lightest at younger birds. The results have shown significant differences (P ? 0,05) in eggshell strength compared to line influence (genotype) and months of age. Eggs from ISA Brown laying hens had much better and eggshell strength than those eggs from DeKalb White. Correlations between eggshell strength and egg weight were with significant (R < 0,05) negative value, which indicating that with increasing egg weight decreases of eggshell strength.


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