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At least 667 records · Page 37Linked to original sources
PubMed1994

GnRH and substance P regulate prostaglandins and sex steroids from reptilian (Podarcis sicula sicula) ovarian follicles and corpora lutea.

The in vitro effects of salmon gonadotropin-releasing hormone (sGnRH), substance P (SP), and their antagonists on prostaglandin F2 alpha (PGF2 alpha), prostaglandin E2 (PGE2), progesterone, androgens, and estradiol-17 beta release by follicles and corpus luteum (CL) of the oviparous lizard, Podarcis sicula sicula, were studied. Follicles and CL were divided according to the different developmental stages; follicles: pre-vitellogenic, early-vitellogenic, mid-vitellogenic, and fully grown; CL: CL1 (unshelled eggs in the oviducts), CL2 (shelled eggs in the oviducts), CL3 (eggs laid 6 hr previously), and CL4 (eggs laid 48 hr previously). SGnRH increased PGF2 alpha and progesterone release by mid-vitellogenic and fully grown follicles; SP increased PGE2 and estradiol-17 beta release by pre-vitellogenic, mid-vitellogenic, and fully grown follicles. SGnRH and SP decreased PGE2 and progesterone and increased PGF2 alpha by CL1 and CL2. The antagonists of these two neuropeptides induced the opposite effects of those of sGnRH and SP. The present data indicate that sGnRH and SP play different roles in the regulation of prostaglandins and sex steroid production by ovarian follicles and CL of P. s. sicula.

Androgens↗
PubMed2006

Avian transgenerational reproductive toxicity test with in ovo exposure.

Ecological risk assessment of environmental pollutants requires effective laboratory assays and extrapolation of the resultant data to wild species. Because avian reproductive disorder and accumulation of persistent compounds in wild birds and their eggs have long been observed in polluted regions, we have developed an assay for investigating whether pollutants accumulated in eggs impair the reproduction of the exposed birds and the survival of the next generation using the Japanese quail. A typical estrogenic compound, diethylstilbestrol (DES), dissolved in olive oil was injected into the air-chamber of fertilized eggs on day 10 of incubation. After sexual maturation of hatched chicks, we mated pairs of male and female quails following an observation period of egg production and collected their eggs. The collected eggs were incubated and checked for the fertility and hatchability, and then the hatchlings were raised and observed in growth for 3 weeks. A dosage of 5 ng/g per egg of DES caused eggshell thinning in eggs laid by exposed females and reduction in eggshell strength. DES also induced shortening of the left oviduct and unexpected development of the right oviduct, while testis weight was reduced symmetrically. The ability of quail pairs to produce offspring was significantly diminished by exposure of females to DES independently of exposure of males, which mainly arose from production of abnormal and inviable eggs. Fertility of normal-shelled eggs and hatchability of fertilized eggs were unchanged regardless of treatments. External morphological abnormalities, which were mostly unopened toes of the foot, were frequently observed in hatchlings from exposed males independently of exposure of females. Additionally, we attempted to extrapolate the experimental results to the northern bobwhite and to predict population trends for quails in a polluted habitat using a population projection model composed of a combination of a Leslie matrix and the logistic equation. In the event of accumulation of an estrogenic compound equivalent to a dosage of 5 ng/g DES in quail eggs, the average population size was predicted to decrease by 20.2% after 1 year, to approximately half after 4 years, and to a fifth after 14 years. When observed weakening of individuals and the risk of egg breakage are taken into consideration, the decline in population was further accelerated. The proposed assay appears to be suitable not only for assessing adverse effects of chemicals on avian reproduction but for population projection of affected wild birds.

Abnormalities, Drug-Induced↗
PubMed1993

PGF2 alpha, PGE2, progesterone, and estradiol-17 beta, secretion by the corpus luteum of the oviparous lizard, Podarcis sicula sicula. In vitro studies.

The release in vitro of prostaglandin F2 alpha (PGF2 alpha), prostaglandin E2 (PGE2), progesterone, androgens and estradiol-17 beta by the corpora lutea (CL) of the oviparous lizard, Podarcis s. sicula, was studied. In addition, the in vitro effects of PGF2 alpha and PGE2 on sex steroid release by CL were evaluated. Corpora lutea were divided into four types, according to their different developmental stage: CL1 (unshelled eggs in the oviduct); CL2 (shelled eggs in the oviduct); CL3 (eggs laid 6 h previously); CL4 (eggs laid 48 h previously) and were placed into culture. PGF2 alpha secretion was highest in CL4 incubated samples and lowest in CL2 and PGE2 was highest in CL1 and CL2. Progesterone secretion was highest in CL2 and lowest in CL4; androgens were not detectable and estradiol-17 beta secretion was highest in CL2. PGF2 alpha decreased progesterone secreted by CL1, CL2 and CL3, while it did not modify release of androgens and estradiol-17 beta. PGE2 did not affect sex steroid release. These data suggest a role of PGF2 alpha in inducing luteolysis, while PGE2 could be implied in the maintenance of CL. A role of progesterone during gestation of Podarcis s. sicula was also confirmed.

Animals↗
PubMed2005

Performance of indigenous, Khaki Campbell and their reciprocal crossbred layer ducks under different management systems.

1. The performance of indigenous ducks (ID), Khaki Campbell (KC) and their reciprocal crossbred layers was studied from 19 to 58 weeks of age. For each genotype, 4 x 18 ducks (3 males + 15 females) were reared under a semi-intensive system (SIS) and an intensive system (IS) with standard management, and 4 x 50 ducks (8 males + 42 females) were reared in an extensive system (ES) with traditional management. 2. In comparison to KC, ID were superior in terms of age at first egg, age at 50% egg production, egg weight, hatchability, eggshell thickness with higher egg shape index. KC ducks were superior to ID in body weight, egg production and feed/kg eggs. Egg quality was similar among the genotypes. Crosses were superior to their parent breeds in age at first egg, egg production and feed/kg eggs. They were also superior to KC in egg weight and egg-shell thickness with a higher egg shape index. 3. The performance of genotypes in the SIS and the IS was similar and superior to the ES except for fertility and yolk colour. 4. Significant heterotic effects were recorded for age at first egg, age at 50% egg production, egg production per duck-day, feed efficiency and egg weight in crosses. Performance was similar in the reciprocal crosses, but superior to their parent breeds.

Age Factors↗
PubMed1995

Prostaglandins and corticosterone in the oviparous female lizard, Podarcis sicula sicula, during reproduction.

The in vitro effects of prostaglandin F2 alpha (PGF2 alpha) and prostaglandin E2 (PGE2) on corticosterone release by ovarian follicles, corpora lutea (CL), and interrenals were studied in the female lizard, Podarcis sicula sicula, during reproduction. Follicles and CL studied in the female lizard, Podarcis sicula sicula, during reproduction. Follicles and CL were divided according to their different developmental stages; follicles: previtellogenic, early-vitellogenic, mid-vitellogenic and fully-grown; CL: CL1 (unshelled eggs in the oviducts), CL2 (shelled eggs in the oviducts), CL3 (eggs laid 6 h previously) and CL4 (eggs laid 48 h previously). Interrenals were divided according to the reproductive stages: pre-vitellogenesis, vitellogenesis, ovulation, post-ovulation, and post-deposition. PGF2 alpha release was highest in fully-grown follicles and PGE2 in early-vitellogenic follicles, corticosterone was highest in pre-vitellogenic and lowest in early-vitellogenic follicles. PGE2 decreased corticosterone in pre-vitellogenic, mid-vitellogenic and fully-grown follicles. PGF2 alpha release was highest in CL4, and PGE2 in CL1 and CL2, corticosterone was highest in CL4. PGF2 alpha increased corticosterone in CL1, CL2 and CL3. In interrenals, PGF2 alpha release was highest and PGE2 lowest during ovulation, corticosterone was highest during ovulation. PGF2 alpha increased and PGE2 decreased interrenal corticosterone during vitellogenesis, ovulation, and post-ovulation. In the plasma, PGF2 alpha levels were highest and PGE2 lowest during ovulation, corticosterone was highest during ovulation. These results suggest that corticosterone, modulated by PGF2 alpha and PGE2, is implied in the reproductive processes with different roles. In fact this steroid could favour ovulatory and luteolytic processes. In addition the hypothesis of an anti-vitellogenic role of corticosterone is discussed.

Animals↗
PubMed1995

Fibrosing granulomas in the equine liver and peritoneum: a retrospective morphologic study.

Fibrosing granulomas were found in the liver and occasionally on the intestinal and diaphragmatic serosae and in the lung of 11 horses submitted for necropsy. Although these granulomas were considered incidental findings in most of the horses, they had caused liver failure in 1 horse. The granulomas typically were characterized by a dense collagenous core that frequently was mineralized. The periphery contained a rim of inflammatory cells. Only in 1 of the 11 horses was there evidence of an egg shell suggestive of schistosomes. Schistosomal eggs were not detected in the feces of the horses. The typical architecture of the granulomas combined with the occasional finding of a residual egg led to the circumstantial conclusion that the fibrosing granulomas were the result of chronic schistosomiasis of undeterminable origin.

Animals↗
PubMed1989

[Peculiarity of pulsed dye laser lithotriptor and its clinical application].

Ultrasound lithotriptors (USL) and electrohydraulic lithotriptors (EHL) are representative lithotriptors for endoscopic elimination of upper urinary tract stones. However, they have some disadvantages. For example, USL can not be used with flexible scopes and EHL can cause unexpected tissue injury. To overcome these problems, the pulsed dye laser lithotriptor (MDL-1, Candera Co.) was developed. The characteristics of this laser lithotriptor and its direct effects on tissue was investigated. This pulsed dye laser lithotriptor generates a 504 nm wavelength green light beam by using a combination of a xenon flash lamp and the greenish dye composed of coumarin solution. The maximum output energy is 60 mJ/pulse and the pulse duration is 1.5 microsecond. The pulse rate can be varied from 1 to 20 Hz. First, the intensity of the shock wave was measured by using a combination of a piezoelectric element and an oscilloscope, and then, the results were compaired with those obtained by a similar experiment with an EHL. The average intensity of the shock wave was 54.4 mW under the conditions of 40 mJ/pulse of output energy and 10 Hz of pulse duration. On the other hand, the EHL generated an average of 54.7 W under the conditions of 400 mJ/pulse output energy. Then, fragmentation of various kinds of urinary stones in saline solution was performed. The results showed that this lithotriptor could fragment almost all kinds of stones except cystine stones. Then, hen's eggs were used to observe the effect if laser bean influenced on the organism immediately behind the photoradiated object. Only the egg shell was demolished but the egg membrane below the eggshell did not undergo any change. After these experiments, skin, liver, kidney and urinary bladder of nude mice and human prostatic urethral mucosa in case of TUR-P were irradiated by this laser. The results showed that laser energy caused slight penetration and localized hemorrhage from the surface of epithelium to subcutaneous tissue. It was confirmed that these effects were generated when the tip of the quartz fiber was in direct contact with the object.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1999

Potassium permanganate staining for differentiation the surface morphology of Opisthorchis viverrini, Haplorchis taichui and Phaneropsolus bonnei eggs.

Potassium permanganate staining method was developed for differentiation Opisthorchis viverrini, Haplorchis taichui and Phaneropsolus bonnei eggs. The surfaces of O. viverrini, H. taichui and P. bonnei eggs stained permanently and temporarily were similar in appearance even the staining procedures were varied both in concentration and time. Determined under light microscope set at 400x, all of these eggs were oval-shaped, operculated at one pole and indistinct small knob at posterior end. O. viverrini eggs showed the distinct musk-melon-like prominent ridges on the surface. Haplorchis taichui eggs had a light striae pattern while P. bonnei eggs had a smooth egg shell. Length of these trematode eggs were significant different (chi2 test, p < 0.05). Mean +/- SD of O. viverrini, H. taichui and P. bonnei eggs were 26.34 +/- 1.65 microm, 29.03 +/- 1.48 microm and 23.00 +/- 1.49 microm, respectively. Regarding of their width, the mean +/- SD of O. viverrini, H. taichui and P. bonnei eggs were 15.54 +/- 0.69 microm. 14.94 +/- 0.91 microm and 12.25 +/- 1.02 microm, respectively. The means of width of O. viverrini and H. taichui eggs were not significantly different (chi2 test, p > 0.05), however, they were significantly different from those of P. bonnei (chi2 test, p < 0.05). Temporary staining using 1% w/v concentration and only 1 minute of time is useful in the mass fecal examination survey for the prevalence and intensity of truly Opisthorchis infection.

Animals↗
PubMed1994

A complete culture system for avian transgenesis, supporting quail embryos from the single-cell stage to hatching.

We report here a method to produce quail hatchlings by culture in vitro from the single-cell stage. The culture is composed of three steps. In the first step, the fertilized ovum surrounded by thick albumen obtained from the magnum is cultured for 24 hr at 41.5 degrees C in a tightly sealed 20-ml plastic cup with chicken thin albumen added to the equator level of the ovum (System Q1). In the second step, a quail egg shell, cut horizontally and emptied, is used as a bed shell. After the thick albumen is removed, the embryo with egg yolk is transferred to the bed shell and thin albumen from chicken eggs is added to fill the shell. Then, the embryo is cultured for an additional 52 hr at 37.5 degrees C while being rocked at an angle of 90 degrees at 30-min intervals (System Q2). The embryo is transferred again to a chicken bed shell and cultured at 37.5 degrees C with rocking at a 30-degree angle (System Q3). Just before hatching, the rocking of embryos is stopped. The procedure yielded a hatchability of 25%. For transgenesis, a plasmid construct containing a beta-actin-lacZ hybrid gene (pMiwZ) is microinjected into the ovum at the single-cell stage, which is cultured in vitro for 85-90 hr using Systems Q1 and Q2 consecutively. Seven out of 17 surviving embryos exhibited lacZ gene expression in embryonic tissues as detected by histochemistry. The procedure described here should be highly applicable for the production of transgenic birds.

Actins↗
PubMed2001

Detection of Salmonella enteritidis in shell and liquid eggs using enrichment and plating.

Detection methods using various enrichment and plating media and immunoconcentration for Salmonella enteritidis in shell and liquid eggs were evaluated. For liquid egg samples naturally contaminated with S. enteritidis, pre-enrichment in 225 ml of buffered peptone water with cysteine followed by selective enrichment in 10 ml of tetrathionate broth was the superior, resulting in the detection of S. enteritidis in all samples on six of the seven types of selective agar substrate investigated. This enrichment procedure also enabled detection of S. enteritidis in most of artificially inoculated shell egg and pasteurized liquid egg samples.

Animals↗
PubMed1991

Contribution to the prophylaxis of chicks aspergillosis: study of the contamination of a hatchery by Aspergillus fumigatus.

Contamination of a hatchery by Aspergillus fumigatus has been studied for 8 weeks from eggs to day old chicks. We have shown that the contamination of the hatchery originates on the egg shell and that each time the eggs are manipulated, spores of Aspergillus fumigatus are thrown into suspension in the air. Thus it seems necessary to bring eggs with as few as possible spores of Aspergillus fumigatus on their shell into the hatchery. Prophylaxis of aspergillosis should be foreseen from the conception of the hatchery: the ventilation system and the internal lay-out should be designed to prevent dispersion and accumulation of Aspergillus fumigatus spores during the processing of the eggs through the hatchery.

Air Microbiology↗
PubMed1984

Mineral content of quail embryos cultured in mineral-rich and mineral-free conditions.

Japanese quail embryos were cultured in mineral rich (MR) using chickens egg shell and mineral-free (MF) using Saran Wrap cultures after 2.5 days of normal incubation. In the MR culture, 82% of embryos survived beyond 14.5 days of incubation and 3 embryos out of 93 (3%) hatched. In the MF culture, 80% survived beyond 9.5 days and 59% beyond 14.5 days. Mineral content (Ca, Mg, K, and Na) of the embryos and of the residual matter within the egg (remaining egg contents excluding the embryo, shell, and shell membrane) were analyzed at 7 to 15 days of incubation. Calcium content of the embryos increased gradually between 9 and 11 days and showed a rapid increase after 11 days in both normal incubation (control) and MR culture. Changes in mineral levels of the embryos plus residual matter within the egg were as follows. Calcium content of the controls increased gradually between 9 and 11 days and showed a rapid increase after 11 days. In MR cultures, Ca increased between 10 and 12 days and showed a rapid increase after 12 days. Magnesium content increased rapidly after 13 days in controls and showed a small increase after 13 days in MR cultures. Potassium and Na content remained constant in both controls and MR cultures. In MF cultures, content of the four minerals remained constant throughout the culture period. Mineral levels of Japanese quail and chicken eggs were compared before and after normal incubation. It was found that 81.5% of Ca and 30.8% of Mg assimilated by newly hatched quail chicks were derived from the egg shell during incubation and 84.2% of Ca and 23.5% of Mg in the chicken.

Animals↗
PubMed1987

Cloning and characterization of a female genital complex cDNA from the liver fluke Fasciola hepatica.

A cDNA clone whose RNA is abundant in the female genital complex of the liver fluke Fasciola hepatica has been isolated from a cDNA library in lambda gt10 by differential screening. The pattern of expression in different fluke tissues and at different stages of miracidium formation suggests that this gene is expressed in the F. hepatica vitelleria. The nucleotide sequence of the cloned cDNA was determined and the primary structure of the putative protein was deduced. The proposed protein is rich in glycine, lysine, and tyrosine and its overall amino acid composition agrees with that reported for the F. hepatica egg shell. The clone has homology with DNA from other trematodes; this homology is higher in organisms in which egg development is similar to that of F. hepatica and suggests that the protein is conserved in organisms in which miracidium formation occurs in fresh water.

Amino Acid Sequence↗
PubMed1994

Relationship of plasma calcium and phosphorus to the shell quality of laying hens receiving saline drinking water.

1. From 36 to 43 weeks of age 210 White Leghorn laying hens were used to study the relationship of plasma calcium and phosphorus concentrations to egg-shell quality when saline drinking water was given. 2. Seven experimental treatments in which different amounts of sodium chloride were supplied by the food and/or the drinking water were compared. 3. Increasing salt intake through the drinking water or the food reduced shell thickness and shell calcium, and increased the numbers of damaged eggs. Sodium chloride given in the drinking water was more effective in reducing shell quality and increasing plasma calcium and phosphorus than sodium chloride given in the food.

Animals↗
PubMed1977

The impact of contamination by organochlorine insecticides on poultry nutrition and feeding.

Nutrient interactions with organochlorine insecticides have been described primarily for vitamin A and protein. Storage of liver vitamin A is reduced by DDT and dieldrin. Low protein diets protect rats from heptachlor toxicity, whereas the toxicity of DDT, dieldrin and lindane is reduced by increasing the quantity and quality of diet protein intake. Biological performance of poultry is adversely affected by 50 to 500 ppm of most of these compounds. Hatchability of eggs and survival of chicks from hens fed insecticides are usually the most sensitive parameters of toxicity. Higher levels of DDT decrease thyroid activity. While several insecticides reduce egg shell thickness in wild birds, such changes are not observed in poultry. Extensive low level contamination of poultry tissues and eggs results from the organochlorine insecticides, with the exception of methoxychlor where tissue residues are not a problem. Tissue and egg accumulation of residues is related to dose but quantitatively different for each organochlorine compound. Tissue withdrawal and excretion takes place slowly and most of the compounds are metabolized by liver hydroxylating enzymes to various derivatives that are also stored in the body. In one case (heptachlor epoxide), the oxidation product is more toxic than the body. In one case (heptachlor epoxide), the oxidation product is more toxic than the parent compound.

Agriculture↗
PubMed1979

pH and calcium concentration changes in a molluscan egg during development.

During development, the egg albumen of calcified land snail eggs becomes more and more acid, correlated directly with a constant rise in the calcium concentration of this albumen. It is suggested that the developing embryo releases some acid metabolite and the subsequent change in albumen pH aids in embryonic absorption of the CaCO3 (calcite) egg shell, used for making the embryonic body shell or skeleton (CaCO3 in the form of aragonite).

Animals↗
PubMed1978

Distribution of gamma-carboxyglutamic acid in calcified tissues.

gamma-Carboxyglutamic acid, previously identified in the vertebrate mineralized tissues of bone and dentin, is not detectable in the calcified skeletons of six invertebrate species representing five phyla. Its absence in all analyzed invertebrate tissues (including calcitic, aragonitic, and apatitic mineral phases) indicates that matrix protein-bound gamma-carboxyglutamic acid is not obligatory for the calcification process in the invertebrates. Further, these data raise the possibility that invertebrates as a group may lack the enzymatic capability for biosynthesizing gamma-carboxyglutamic acid. In contrast, the distribution of gamma-carboxyglutamic acid in the vertebrates has been further extended by this study to include an apatitic shark tooth and an aragonitic fish otolith. No gamma-carboxyglutamic acid was detected, however, in the organic matrix of the calcitic hen egg shell.

1-Carboxyglutamic Acid↗
PubMed1975

[Biosynthesis of phorcabiline, blue-green biliary pigment of Actias selene (Lepidoptera, Attacidae)].

The blue-green bile pigments of Actias selene (Attacidae) have been investigated at different stages of its development. Coproporphyrinogen-14-C, protoporphyrin-IX3-H, and pterobilin-14-C, injected to larvae are metabolised into phorcabilin I, the main neopterobilin in this animal. It is concluded that phorcabilin I is a bile pigment of the IX gamma series and that pterobilin is its direct precursor. A method for the preparation of labelled protoporphyrin from quail egg-shell is reported.

Age Factors↗