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Results 351 - 400 of 591
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Chapman T - - 1998
Costs of reproduction include costs of producing eggs and of mating itself. In the present study, we made an experimental investigation of costs of reproduction in the Mediterranean fruit fly (medfly, Ceratitis capitata). We demonstrated that virgins live longer than non-virgin females. However, in strong contrast to most findings within ...
Bousseau S - - 1998
The addition of components of animal origin (egg yolk, milk) to most commercial diluents used to freeze bull semen represents a potential risk of contamination of the doses with bacteria or mycoplasma. A series of quantitative and qualitative analyses were performed to detect microbiological contamination observed in Biociphos plus (a ...
Blus L J - - 1998
Eggs of Forster's terns (Sterna forsteri) collected in 1991 from nesting colonies on Crescent Island (Columbia River) and the Potholes Reservoir in south central Washington generally contained low residues of organochlorine pesticides and metabolites, 2,3,7, 8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and polychlorinated biphenyls (PCBs). Hepatic cytochrome P450 enzyme activity in pipped embryos of ...
Furusawa N - - 1998
Sulphamonomethoxine (SMM) or sulphadimethoxine (SDM) were fed each to four laying hens at a dietary content of 400 p.p.m. 1000 p.p.m. of chromic oxide were supplemented to the experimental diets as an indicator for the absorbability in the gastrointestinal tract. SMM and SDM contents (p.p.m.) in the large intestine, determined ...
Clark N - - 1998
Once upon a time, eggs were considered a "breakfast of champions." Just about every active, hard-working person enjoyed them fried, scrambled, poached, or even raw in eggnog and protein drinks. Then, Americans became cholesterol-conscious and began to substitute bagels, cereal, and other high-carbohydrate, low-cholesterol breakfast foods.
Indar L - - 1998
The aim of this study was to determine whether the contents of farm eggs in Trinidad are contaminated with Salmonella and if transovarian transmission occurs. 750 fresh eggs from 10 farms supplying 75% of the country's eggs were cultured for Salmonella. Salmonella was found on the egg shells' surfaces from ...
Moravec F - - 1998
Two new species of trichuroid nematodes. Huffmanela japonica n. sp. and Huffmanela shikokuensis n. sp., are established on the basis of their egg morphology and biological characters; the eggs of both species occur in the musculature of marine fishes from the Inland Sea of Japan. The dark-shelled eggs of H. ...
Pearson J T - - 1998
Our aim was to examine changes in heart rate (fh) during the embryonic and posthatching periods of the smallest precocial avian species, Coturnix chinensis. In experiment I, repeated measurements of mean fh were made for individual quail by ballistocardiogram (BCG) during incubation, and by both piezo-electric film and electrocardiogram (ECG) ...
Suzuki Y - - 1998
Physiological and morphological comparisons were made between the short-winged (SW) and long-winged (LW) morphs of a cricket, Modicogryllus confirmatus, to determine the cost of the flight capacity and the physiological mechanisms underlying trade-offs between different life history traits related to migration and reproduction. Both wingmorphs grew at a similar rate ...
Gentle M J - - 1997
1. To examine the effects of beak trimming on behaviour, beak anatomy, weight gain, food intake and feather condition 360 ISA Brown chicks were trimmed by hot cut or cold cut at 1 d or 10 d of age or were sham-operated controls. The experiment was a 3 x 2 ...
Nieves E - - 1997
To determine the influence of physical factors on oviposition of Lutzomyia migonei (Diptera: Psychodidae) under laboratory conditions, two sets of experiments were performed. The first test was to determine the influence of the size of pots on oviposition. Gravid flies were placed individually or in groups in different oviposition pots. ...
Zahler M - - 1997
The species status of Dermacentor marginatus and Dermacentor reticulatus was evaluated by scanning electron microscope (SEM) examination of adult ticks, cross-breeding experiments and molecular biological analysis of eggs derived from transspecific pairings. The SEM investigations including the morphometric quantification of phenotypic features resulted in an unequivocal differentiation of adult D. ...
Brittan-Powell E F EF Department of Psychology, University of Maryland College Park 20742-4411, - - 1997
Budgerigars have a complex vocal repertoire, some of which develops through learning. The authors examined the course of vocal development in budgerigars from hatching to about 4 weeks postfledging (approximately 85 days old). Food-begging calls showed changes in duration, peak frequency, bandwidth, and frequency modulation with age. Within a week ...
Duesbery N S - - 1997
CENP-E, a kinesin-like protein that is known to associate with kinetochores during all phases of mitotic chromosome movement, is shown here to be a component of meiotic kinetochores as well. CENP-E is detected at kinetochores during metaphase I in both mice and frogs, and, as in mitosis, is relocalized to ...
Kobayashi Y - - 1997
To investigate the relationship between postprandial electrogastrographic changes and parasympathetic nervous activity, 10 healthy adult males (20 to 29 years old) volunteered for EGG recording in the following conditions: 1) butylscopolamine bromide (scopolamine) administration to block parasympathetic nervous activity; 2) after food intake; and 3) during a postprandial period after ...
McEdward L R - - 1997
Fecundity-time models of reproductive strategies in marine invertebrates all predict that reproductive success is maximized only at the extreme levels of investment. Selection should drive egg sizes toward small eggs and planktotrophy or large eggs and lecithotrophy. The existence of two distinct larval types, feeding and nonfeeding, has been taken ...
Iwao Y - - 1997
The unfertilized egg of the newt, Cynops pyrrhogaster, has a second meiotic spindle at the animal pole and numerous cortical cytasters. After physiologically polyspermic fertilization, all sperm nuclei incorporated into the egg develop sperm asters, and the cortical cytasters change into bundles of cortical microtubules. The size of the sperm ...
Oxynos S K - - 1997
Minimisation of PCDD/F emissions leads to a decreasing burden of the bioindicator herring gull egg in the last few years. Unfortunately, the river Elbe sediment is highly polluted with PCDD/F. The temporal burden of the sediment is fluctuating. Due to the different intake and type of feed differences of the ...
Lewis P D - - 1997
1. ISA Brown and Shaver 288 pullets were changed from 8 h to 8, 10, 13 or 16 h photoperiods at 42, 63, 84, 105, 126 or 142 d of age. 2. Age at first egg (AFE) was curvilinearly affected by the size and timing of the change in photoperiod. ...
Bradford M A - - 1997
The ability of two strains of Salmonella enteritidis PT4 to cross-contaminate from inoculated egg droplets on surfaces onto melon or beef (sterile or non-sterile) was investigated. When the foods were placed on these surfaces where egg droplets were still wet, cross-contamination occurred within 1 s onto every piece of food. ...
Frémont S - - 1997
An egg protein, lysozyme, is a still unlabeled additive currently used in cheese preparation. Furthermore, the WHO-FAO committee considers it innocuous. However, 31% of children and 8% of adults with food allergies are allergic to eggs. This work aimed to determine the percentage of patients sensitized to lysozyme from a ...
R' kha S - - 1997
In the evolutionary process during which Drosophila sechellia became specialized on a toxic fruit (morinda), a spectacular decrease in female reproductive capacity took place when compared with the species' generalist relatives D. mauritiana and D. simulans. Comparisons of species and interspecific crosses showed that two different traits were modified: number ...
Abe N - - 1997
Toxocara spp. eggs were detected from 30 (75%) out of 40 sandpits of parks, in Osaka city. This prevalence was higher compared to those reported other areas of Japan. Since we examined a large quantity of sample, this could have resulted to higher prevalence. The number of eggs recovered decreased ...
Bringe N A - - 1997
A dry egg yolk ingredient called Eggcellent has 74% less fat and 90% less cholesterol than liquid egg yolks, when reconstituted on an equal protein basis. The phospholipids and proteins are retained, enabling the ingredient to have the taste and texturizing properties of fresh egg yolk. Using the new yolk, ...
Henry T R - - 1997
Toxicity and histopathology of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in zebrafish (Danio rerio) early life stages was characterized from 12 to 240 hr postfertilization (hpf) following water-borne exposure of newly fertilized eggs. TCDD did not increase egg mortality (0-48 hpf), nor did it affect time to hatching (48-96 hpf). Egg doses of 1.5 ...
Lewis P D - - 1996
1. The effects of constant photoperiods and of single (5 h) changes in photoperiod applied at 12 or 17 weeks of age upon age at first egg (AFE) were studied using ISA Brown and Shaver 288 pullets. 2. Birds reared from 2 d of age until after maturity on constant ...
Bishop C A - - 1996
Common snapping turtle (Chelydra serpentina serpentina) eggs from five sites within the Great Lakes basin, and from a reference site in north-central Ontario were collected during 1981-1991 and analyzed for four organochlorine pesticides, polychlorinated biphenyls (PCBs) including six non-ortho PCBs, polychlorinated dibenzodioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). The pattern of ...
Stadelman W J - - 1996
A small percentage of all eggs may be contaminated with Salmonella enteritidis (SE). To eliminate this hazard from the food supply, procedures for pasteurizing eggs in the shell have been developed. At least four research groups are attempting to devise a process to achieve a pasteurized shell egg. Only one ...
Sheldon B W - - 1996
Over the past decade, advances in egg processing technologies have permitted commercial production of ultrapasteurized liquid whole egg (LWE) products with a shelf-life of greater than 10 wk at 4 C. The inactivation and control of psychrotrophic pathogens such as Listeria monocytogenes and Aeromonas hydrophila in extended shelf-life LWE and ...
Jianmongkol S - - 1996
The cholinergic toxicity of malathion is exacerbated by its isomerization product, isomalathion, which inhibits detoxifying carboxylesterases as well as target acetylcholinesterase (AChE). Previous work has shown that the four stereoisomers of isomalathion, (1R, 3R), (1R, 3S), (1S, 3R), and (1S, 3S), differ in their inhibitory potencies against either rat brain ...
Barry M J - - 1996
The toxicity of the organochlorine pesticide, endosulfan, to Daphnia carinata was measured at three levels of biological organization: allocation of resources to reproduction, growth and reproductive rates, and population dynamics. The mechanisms by which responses at one level of organization manifest at higher levels are discussed. Two experiments were performed: ...
Lokhorst C - - 1996
The objectives of this study were 1) to compute appropriate mathematical curves that describe the daily production process by the input variables daily feed consumption, water consumption, ambient temperature, and output variables hen-day egg production, egg weight, second grade eggs, floor eggs, cumulative mortality, body weight, and flock uniformity; and ...
Schwabl H - - 1996
The eggs of the canary (Serinus canaria) contain variable doses of maternal testosterone. The reported experiments investigated whether testosterone influences nestling growth and how this interacts with differences of the growth of nest mates that are caused by asynchronous hatching. Injections of testosterone into the yolk of unincubated eggs enhanced ...
Kyarisiima C C - - 1996
1. Commercial pullets were grown at cool (10 degrees -20 degrees C) or hot (25 degrees -35 degrees C) temperatures to similar bodyweights at 18 weeks of age. Between 18 and 50 weeks the birds were either kept at the same temperatures as during growth or transferred to the alternate ...
Chadee D D - - 1996
The oviposition patterns of Anopheles aquasalis Curry collected from a grass swamp in Gloudon, Caroni Swamp, Trinidad, were studied in the laboratory by recording the egg-laying performance of 30 individuals and a group of 150 females at 2-h intervals. Oviposition was nocturnal, with a peak between 2400 and 0400 hours ...
Murk A J - - 1996
In eight Dutch or Belgian common tern (Sterna hirundo) colonies, breeding biology and food choice were determined, and 15 second eggs were collected from three-egg clutches for artificial incubation, biochemical analysis and analysis of yolk-sac polyhalogenated hydrocarbon (PHAH) levels. Results from these analyses were combined with biological data from the ...
Anisuzzaman M - - 1996
1. One hundred and forty four Shaver broiler chicks (Starbro 15) were reared from 4 d to 56 d of age on 4 types of litter: sawdust, paddy straw, sand and rice husk each spread to a depth of 75 mm. 2. Birds reared on rice husk litter showed the ...
Jansen M - - 1996
World trade in live salmonid embryos (eyed eggs) has grown in response to increased global salmon production, particularly in South America, and parallels international trade in farmed salmonid products. Rainbow trout (Oncorhynchus mykiss), Atlantic salmon (Salmo salar) and coho salmon (O. kisutch) are the most commercially important species. In 1992, ...
Todd E C - - 1996
In 1992, Agriculture and Agri-Food Canada (AAFC) amended its Egg Regulations to restrict movement of Canada C eggs (cracks) to federally registered processed egg stations for pasteurization. This was questioned by egg producers and some provinces on economic grounds. It was also in conflict with long-standing practices of marketing eggs ...
Abdulrahim S M - - 1996
1. The influence of Lactobacillus acidophilus alone or in combination with zinc bacitracin on the performance of laying hens was monitored over a period of 4 months. 2. Lactobacillus acidophilus improved egg production, food conversion and reduced the cholesterol concentration in the eggs, but zinc bacitracin had no effect when ...
Lewis P D - - 1996
1. ISA Brown and Shaver 288 hens, fed ad libitum, were given a 5-h increase or a 2, 5 or 10-h decrease in photoperiod at 215 d of age. Hens of both breeds were also maintained on constant 10, 13 or 18 h photoperiods. Other groups had their photoperiod increased ...
Van Horne P L - - 1996
1. In the Netherlands aviary systems are in use on 19 commercial farms. In the present study the results of 19 flocks kept in aviaries, with an average flocksize of 16,000 hens, were analysed and compared with 47 flocks kept in battery cages. 2. The aviary flocks had lower egg ...
Chambers G M - - 1996
Mechanisms initiating autogenous egg development were studied using a selected strain of Asian tiger mosquito, Aedes albopictus (Skuse), that required a sugar meal to develop eggs autogenously. Caloric intake and the abdominal distention produced by ingesting sucrose solutions were interrelated in their effects on autogeny. Distention of the abdomen with ...
Lewis P D - - 1996
1. ISA Brown pullets were given an 8-h photoperiod and fed ad libitum to 63 d of age. At 63 d the photoperiod was either kept at 8 h or increased to 13 h, and the photostimulated birds were subjected to 1 of 3 feeding systems: ad libitum, 8 h ...
Millam J R - - 1996
Cockatiel eggs hatch asynchronously because most eggs are laid after continuous incubation begins. We manipulated numbers of eggs in the nest after cockatiels began incubating to determine whether the number of eggs in the nest influenced clutch size. We also measured plasma prolactin 2, 7, 12, and 17 days after ...
Williams R B - - 1996
An investigation was made of the relationship between the water and food consumption of healthy and sick chickens Using coccidiosis as a disease model, and uninfected chickens as healthy controls, male birds of an egg-production breed and males and females of a meat-production breed were found to have simultaneously reduced ...
Dangjin L - - 1996
This paper deals with a new egg count technique for Macracanthorhynchus hirudinaceus and Ascaris suum. The making of the new counter and the operation are described. The eggs of M. hirudinaceus in the upper, the middle and the lower levels of the sediment from swine feces were counted by the ...
Wheeler D - - 1996
Oogenesis in insects is typically a nutrient-limited process, triggered only if sufficient nourishment is available. This nourishment can be acquired during the larval or adult stage, depending on the insect. Timing of food intake will have major effects on mechanisms of hormonal control. When nourishment for eggs is taken primarily ...
Omar A H - - 1995
Chrysomyia albiceps often feeds to repletion and then regurgitates a portion of the food, a behaviour that heightens its importance as a mechanical vector of enteric pathogens. Pupae of this fly are susceptible to the attack of the parasitic wasp, Nasonia vitripennis in the laboratory as well as in nature ...
Morris T R - - 1995
1. Pullets of 2 high-producing commercial stocks (both brown-egg layers) were exposed to 5 different lighting patterns between 18 and 72 weeks to test the hypothesis that photoperiods used in commercial lighting programmes early in the laying year may be unnecessarily long and, by accelerating the development of photorefractoriness, may ...
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