Live Eggs (live + egg)

Distribution by Scientific Domains


Selected Abstracts


A nonlethal microsampling technique to monitor the effects of mercury on wild bird eggs

ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2009
Katherine R. Stebbins
Abstract Methylmercury is the predominant chemical form of mercury reported in the eggs of wild birds, and the embryo is the most sensitive life stage to methylmercury toxicity. Protective guidelines have been based mainly on captive-breeding studies with chickens (Gallus gallus), mallards (Anas platyrhynchos), and ring-necked pheasants (Phasianus colchicus) or on field studies where whole eggs were collected and analyzed and the effects of the mercury were measured based on the reproductive success of the remaining eggs. However, both of these methods have limitations. As an alternative, we developed a technique that involves extracting a small sample of albumen from a live egg, sealing the egg, returning the egg to its nest to be naturally incubated by the parents, and then relating the hatching success of this microsampled egg to its mercury concentration. After first developing this technique in the laboratory using chicken and mallard eggs, we selected the laughing gull (Larus atricilla) and black-necked stilt (Himantopus mexicanus) as test subjects in the field. We found that 92% of the microsampled laughing gull eggs met our reproductive endpoint of survival to the beginning of hatching compared to 100% for the paired control eggs within the same nests. Microsampled black-necked stilt eggs exhibited 100% hatching success compared to 93% for the paired control eggs. Our results indicate that microsampling is an effective tool for nonlethally sampling mercury concentrations in eggs and, as such, can be used for monitoring sensitive species, as well as for improving studies that examine the effects of mercury on avian reproduction. [source]


Creation of artificial upwelling areas for brown trout, Salmo trutta, spawning in still water bodies

FISHERIES MANAGEMENT & ECOLOGY, Issue 5 2006
Å. BRABRAND
Abstract, Brown trout, Salmo trutta L., spawning sites were constructed by creating areas of artificial upwelling water, 252 ± 37 mL m,2 min,1 (95% CL), through appropriately sized spawning gravel substrate in 3 m2 vessels buried in the bottom of a 150-m2 pond. Natural spawning occurred in the vessels during autumn 2001,2004, with hatching and alevin swim up the following spring. In areas of upwelling, egg survival was 85,95%, while no live eggs were observed in areas without upwelling. In areas with upwelling, the maximum density of live eggs at the eyed stage was 570,1510 eggs m,2. In spring 2004 and 2005, the density of alevins was estimated at 322 (±187) m,2 and 567 (±217) m,2, respectively, in areas with upwelling water, compared with 35.2 ± 25.4 m,2 in areas without upwelling water in 2004. [source]


Comparative efficacy of two nit combs in removing head lice (Pediculus humanus var. capitis) and their eggs

INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2007
Rick Speare BVS
Background, Fine tooth lice combs fall into two classes based on the material from which their teeth are made: plastic or metal. Metal combs are further divided into those that are made from a flat sheet of metal, and hence have rectangular teeth, and those that have cylindrical teeth embedded in a plastic base. Methods, The efficacy of two fine tooth combs [Lice Meister comb (metal) and Lady Jayne comb (plastic)] in removing head lice (Pediculus humanus var. capitis) and their eggs from the hair of children was evaluated after treatment with a viscous head lice product (Lice Blaster; Emerald Forest Pharmaceuticals Pty Ltd, Currumbin, Qld, Australia). The hair of 27 children was divided into two sections sagitally, and each comb was randomly assigned to one half of the hair, and the lice and eggs removed by the combs were counted. Results, In 96% of subjects, the Lice Meister comb removed more eggs than the Lady Jayne comb, with an average of three to four times more hatched, dead, and live eggs removed. The Lice Meister comb removed more lice than the Lady Jayne comb in 10 subjects, the same in eight subjects, and less in nine subjects. Conclusion, Overall, the Lice Meister comb is recommended as a more effective comb for use in controlling head lice infestations, whether employed with conditioner or with insecticide treatment. This appears to be the first study investigating the efficacy of nit combs in vivo. Further research is needed to determine which characteristics of fine tooth combs are the most important in removing head lice eggs. [source]


Resistance of perch eggs to attack by aquatic fungi

JOURNAL OF FISH BIOLOGY, Issue 3 2000
C. G. M. Paxton
In the distinctive gelatinous Perca fluviatilis egg mass, limited fungal growth by Aphanomyces and Saprolegnia spp. especially S. diclina, occurred within dead eggs but did not spread to adjacent live eggs. Perch eggs exposed to parasitic challenge by Saprolegnia parasitica, S. dieclina (type III) and S. ferax, under fluctuating temperature regimes replicating spring water temperatures, did not have significantly greater mortality than did unchallenged controls. The observations suggest that perch eggs have some anti-fungal properties which usually prevent the spread of fungus throughout the egg mass and that under normal spring temperatures there should be negligible ecological consequences of fungal infection in perch egg masses. [source]