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At least 991 records · Page 55Linked to original sources
PubMed1979

The metabolism of cholecalciferol in the liver of Japanese quail (Coturnix coturnix japonica) with particular reference to the effects of oestrogen.

1. Studies were carried out in vitro with the livers of Japanese quail that had been fed from hatching on diets supplying their full requirements for vitamin D. 2. 25-Hydroxycholecalciferol was the major metabolite when liver homogenates of egg-laying female and oestrogen-treated quail of both sexes were incubated with [3H]cholecalciferol. 3. Very little 25-hydroxycholecalciferol was generated from liver homogenates of adult male and immature quail. Instead the cholecalciferol was converted into one or more compounds less polar than 25-hydroxycholecalciferol and into a number of highly polar metabolites, some of which were water-soluble. 4. Oestrogen not only stimulated the 25-hydroxylation of cholecalciferol but also protected both cholecalciferol and 25-hydroxycholecalciferol from degradation by the enzymic pathways active in immature and male birds. 5. These actions of oestrogen may be of physiological significance in relation to the high requirements of laying birds for 1,25-dihydroxycholecalciferol to support the intense metabolism of calcium associated with egg-shell calcification.

Aging↗
PubMed2003

Detection and survival of Campylobacter in chicken eggs.

AIMS: Campylobacter jejuni, a food-borne human pathogen, is widespread in poultry; however, the sources of infection and modes of transmission of this organism on chicken farms are not well understood. The objective of this study was to determine if vertical transmission of C. jejuni occurs via eggs. METHODS AND RESULTS: Using a temperature differential method, it was shown that Campylobacter had limited ability to penetrate the eggshell. When C. jejuni was directly inoculated into the egg yolk and the eggs were stored at 18 degrees C, the organism was able to survive for up to 14 days. However, viability of C. jejuni was dramatically shortened when injected into the albumen or the air sac. When freshly laid eggs from Campylobacter-inoculated specific pathogen-free (SPF) layers were tested, C. jejuni-contamination was detected in three of 65 pooled whole eggs (5-10 eggs in each pool) via culture and PCR. However, the organism was not detected from any of the 800 eggs (80 pools), collected from the same SPF flock, but kept at 18 degrees C for 7 days before testing. Likewise, Campylobacter was not recovered from any of 500 fresh eggs obtained from commercial broiler-breeder flocks that were actively shedding Campylobacter in faeces. Also, none of the 1000 eggs from broiler breeders obtained from a commercial hatchery were positive for Campylobacter. CONCLUSIONS: These results suggest that vertical transmission of C. jejuni through the egg is probably a rare event and does not play a major role in the introduction of Campylobacter to chicken flocks. SIGNIFICANCE AND IMPACT OF THE STUDY: Control of Campylobacter transmission to chicken flocks should focus on sources of infection that are not related to eggs.

Animal Husbandry↗
PubMedDate not supplied

[Embryonic development of 2 Phyllobothriidae (Cestoda: Tetraphyllidea)].

Caulobothrium longicolle (Linton, 1890) and Phyllobothrium gracile (Weld, 1855) (Cestoda: Tetraphyllidea, Phyllobothriidae) have the same embryonic development with the following characteristic data: --a small number of vitelline cells (2 or 3) pass with the zygote in the ootype;--a non operculate thin egg-shell;--the entire and equal zyhote cleavage following by unequal divisions leading to the formation of four blastomere types (Macromeres, secondary Macromere, Mesomeres and Micromeres);--the differentiation of two syncytial embryonic envelopes during the preoncospheral phase. The outer envelope encloses the vitelline material remnant and three Macromeres among which the secondary Macromere. The inner envelope or embryophore, originates from five or six Mesomeres;--the presence of the oncospheral membrane;--the Phyllobothriidae ontogenesis is similar to that of the Onchobothriidae. By their embryonic features, the Tetraphyllidea are close to the Cyclophyllidea. This similarity suggests a phylogenic relationship between those two Cestoda orders.

Animals↗
PubMed1982

[Kahmannia eliomydis n. gen., n. sp. (Nematoda: Heteroxynematidae), an intestinal parasite of Eliomys quercinus (Linnaeus, 1766)(Rodentia: Gliridae) in Minorca (Balearic Islands)].

Description of Kahmannia eliomydis n. gen., n. sp., an Heretoxynematid Nematode parasitizing the intestine of the Garden dormouse Eliomys quercinus (Linnaeus, 1766) (Rodentia: Gliridae) in the island of Minorca (Balearies). Kahmannia n. gen. is proposed to include in the Heteroxynematinae the intestinal parasites from Rodents characterized by: oral opening circular without lips; buccal capsule triangular with small oesophageal teeth; oesophagus elongated with spherical bulb with strongly developed valves, clearly individualized and separated by a well-defined oesophageal isthmus; cephalic vesicle present, with sinuous peribuccal ornamentation forming slender crown with eight digitations; cuticular striations marked; lateral and cervical alae absent; male without caudal lateral alae, without precloacal cuticular ornamentation on ventral surface and without gubernaculum, but with single spicule; and thin-shelled eggs without operculum. It is the first Nematode Oxyuroidea known parasitizing Rodents Glirimorpha.

Animals↗
PubMed1988

[Capillaria brochieri n. sp. (Nematoda: Capillariinae) intestinal parasite of the chimpanzee (Pan paniscus) in Zaire].

Capillaria brochieri n. sp. is described in a chimpanzee (Pan paniscus Schwartz, 1929) deceased from diarrhea. The male shows a unique structure of the caudal extremity: two flat paddles, with distal insertion, extend forward on each side of the ventral genital opening. The spicule (1,750 microns in length) shows a flattened anterior extremity and a tapered, curved posterior extremity. The cirrus is non-spiny and very long. Two narrow and very long lateral alae are present. The female bears a vulvar appendage. The egg shell shows an internal dense layer and an external layer of irregular width, showing pores and striations. The paper includes a study of the literature on Capillaria and Anatrichosoma from Primates and Man. C. brochieri is the first species of Capillaria described from the intestine of the chimpanzee. Because of the close analogies between chimpanzee's and man's helminthes, it is possible that C. brochieri has to be considered in human pathology.

Animals↗
PubMed1989

[Granulomatous colitis with pseudopolyp in schistosomiasis].

A 26-year-old Arab had epigastric pain and bloody mucous stools. At coloscopy distal proctitis and a polyp at the rectosigmoid junction were discovered. The polyp had granulomatous inflammatory changes and eggs of Schistosoma mansoni with a characteristic egg shell, central miracidium and lateral spine. Bilharziasis should be considered in the differential diagnosis of chronic inflammatory disease of the intestines.

Adult↗
PubMed1977

Calcium-binding protein of chorioallantoic membrane: identification and development expression.

A calcium-binding protein (CaBP) which has a molecular weight of 100,000 and an isoelectric point of 8.0 has been isolated from the chorioallantoic membrane (CAM) of the chick embryo. Expression of the CaBP occurs simultaneously with the onset of calcium absorption from the egg shell by the CAM, and the temporal increase in CaBP activity is coincident with calcium deposition in the embryo. The CAM CaBP differs in properties from the CaBPs of the adult organs, including the vitamin-D-dependent protein of intestine.

Adenosine Triphosphatases↗
PubMed1986

Characterization of a female-specific cDNA derived from a developmentally regulated mRNA in the human blood fluke Schistosoma mansoni.

We have isolated and characterized a cDNA clone that is derived from a developmentally regulated mRNA found only in mature female schistosomes. The mRNA is approximately 950 nucleotides in length and is not detectable in immature female schistosomes isolated from single-sex infections, in male worms, or in eggs. During normal bisexual infections, the mRNA species is first detected 28 days after infection (the time of worm pairing) and increases to a high level 35 days after infection, coinciding with the start of egg production. The nucleotide sequence of the cDNA shows two large open reading frames in the coding strand. Several features of the clone, including the deduced sequence of the polypeptide encoded by one of the reading frames, suggest a relationship to the silk moth chorion (egg shell) gene family. The isolation of this clone provides us with a probe for further studies of female schistosome development and is a first step toward a detailed understanding of this process at the molecular level.

Amino Acid Sequence↗
PubMed1996

Identification of chitinase as the immunodominant filarial antigen recognized by sera of vaccinated rodents.

Acanthocheilonema viteae is a parasitic nematode of rodents. We identified the chitinase of A. viteae infective stage larvae (L3) as the main target of the humoral immune response of jirds, which were protected against challenge infection after vaccination with irradiation attenuated L3. The cDNA of the L3 chitinase has been sequenced, and the deduced amino acid sequence shows significant homologies to chitinases of Brugia malayi microfilariae, insects, yeast, bacteria, and Streptomyces sp. The protein has been characterized by monoclonal antibodies and substrate activity gels. The chitinase of L3 may contribute to degrading the nematode cuticle during molting and thus represents a target of protective immune responses in a phase where the parasite is highly vulnerable. In addition, it has been shown that a similar enzyme exists in uterine microfilariae, which probably has a role in casting the egg shell.

Amino Acid Sequence↗
PubMed2004

The ability of laying hens to regulate phosphorus intake when offered two feeds containing different levels of phosphorus.

The ability of laying hens to adjust their intake of available P (AP) was investigated with a maize-soyabean diet fed to forty-eight individually caged birds in a 2 x 4 factorial experiment. From 19 to 25 weeks of age (phase 1) twenty-four birds were fed a normal-P (NP) diet (2.2 g AP/kg DM) and twenty-four were fed a low-P (LP) diet (1.1 g AP/kg). LP eggs were lighter (51 v. 54 (SEM 1.0) g; P<0.05), providing evidence that the LP diet was deficient in AP. From 25 to 28 weeks of age six hens from each phase 1 treatment were fed either the NP or LP diet alone or a choice of the LP and NP feeds or a choice of the LP feed and a phytase-supplemented (PP) feed (LP diet with 400 microbial phytase units/kg). With a choice of the NP and LP feeds, the hens fed the LP diet in phase 1 ate a smaller proportion of the LP feed (34 (SEM 12.0) %) than the hens fed the NP diet in phase 1 (72 (SEM 12.0) %; P<0.05), showing that P deficiency influenced subsequent selection for AP, i.e. an appetite for P was demonstrated. In those birds offered the LP and PP feeds, the presence of phytase in one of the two feeds significantly alleviated the effect of P deficiency on egg and body weights. The proportion of the LP diet chosen was not significantly affected by phase 1 treatment; it was not necessary for the hens to eat more than 50 % of PP feed.

6-Phytase↗
PubMed1997

Research notes from the Onchocerciasis Chemotherapy Research Centre, Ghana.

Brief notes are given on drugs which have been tested at the Onchocerciasis Chemotherapy Research Centre at Tamale and Hohoe and found to have activity against Onchocerca volvulus. Ivermectin in single doses as high as 800 micrograms/kg was found to be no more effective than the standard dose of 150 micrograms/kg. The benzimidazole carbamates, mebendazole and albendazole, differ in their effects on O. volvulus. The former has microfilaricidal effects and is toxic to developing embryos surrounded by an egg shell but not the stretched microfilariae. Albendazole has no microfilaricidal activity but is toxic to all intra-uterine stages. The reasons for these differences are unclear. Early studies with amocarzine are described; the maximum tolerable dose is 20 mg/kg and the predominant activity, against the microfilariae, is marked only at doses greater than 12 mg/kg. None of the drugs tested has macrofilaricidal activity.

Albendazole↗
PubMed2004

Effect of alfalfa meal in diets of laying quails on performance, egg quality and some serum parameters.

This study was conducted to investigate the effects of increasing levels of alfalfa meal in the diet of laying quails on egg production, feed consumption, feed efficiency, egg quality, egg yolk cholesterol and selected serum parameters. In this study, 192, 10-week old quails (Coturnix coturnix japonica) were evenly distributed to four groups with four replicates of 12 quails each. The control group was fed a basal diet containing 0% alfalfa meal and the remaining groups received 3, 6 or 9% alfalfa meal for 12 weeks. Live weight, feed consumption, and egg production were recorded and feed efficiency were calculated. Eggs were examined for interior and exterior quality and egg yolk cholesterol content. At the end of the experiment, blood samples were collected and sera were analysed for serum Ca, inorganic P (P(i)), Mg, triglycerides and total cholesterol. Any level of alfalfa meal had no effect on live weight, egg production, feed consumption, feed efficiency, egg weight, and egg yolk index. Six percent and 9% alfalfa meal increased specific gravity of whole egg and eggshell thickness as well as serum P(i) levels. Nine percent alfalfa meal reduced serum triglycerides, total cholesterol levels and egg yolk cholesterol content. The results of this experiment indicated that addition of 9% alfalfa meal into the laying quail diet may improve eggshell quality and reduced serum triglycerides and serum and egg yolk cholesterol without any adverse effect on performance.

Animal Feed↗
PubMed2003

Effect of hens fed dietary flaxseed with and without a fatty liver supplement on hepatic, plasma and production characteristics relevant to fatty liver haemorrhagic syndrome in laying hens.

1. Two long-term experiments were conducted with Single Comb White Leghorn (SCWL) hens (line UCD-003) predisposed to fatty liver haemorrhagic syndrome (FLHS). The first investigated the effect of adding a fatty liver supplement to the diet of laying hens prior to the onset of lay, and continuing either until peak production or throughout 39 weeks into lay. The second experiment, lasting 9 months into lay, investigated the effect of adding a fatty liver supplement, with or without 100 g/kg dietary ground flaxseed, to the diet. Body weight, feed intake, plasma triglycerides (in experiment 2) and egg production were measured throughout the experiment. Liver weight, liver fat content, liver malondialdehyde (MDA) content and liver haemorrhage score and fatty acid content of liver fat (in experiment 2) were measured at the end of each experiment. 2. In experiment 1, hens given diets containing the fatty liver supplement had higher egg production and eggshell strength, but there was no difference in liver parameters including MDA content or haemorrhage score compared with controls. 3. At the end of experiment 2, hens on 100 g/kg flaxseed diets had lower body weight, liver weight, liver dry matter and fat content, and plasma triglyceride concentrations than hens given the control diets. 4. Liver haemorrhage score was positively correlated with liver weight, but not with liver fat content, plasma triglyceride concentration or liver MDA content. This suggests that reducing the liver lipid content or feeding fatty liver supplements may not be as effective in controlling FLHS as controlling the size of the liver.

Animal Feed↗
PubMed2003

Microbial contamination of artificially incubated Greater Rhea (Rhea americana) eggs.

1. This paper is a report of biological agents that contaminate Greater Rhea (Rhea americana) eggs during artificial incubation. 2. The cleanliness of eggs when collected, and the period of storage prior to incubation, were investigated to assess their effects on microbial contamination and hatchability. 3. A total of 14 bacteria and 4 fungi species were isolated within the egg in the laboratory. 4. Microbial contamination was higher (24%) in very dirty eggs than in eggs which were clean or dirty (16%). Hatching success was lower (30%) for very dirty eggs, compared with 42% for clean or dirty eggs. 5. The percentage of microbial contamination of stored eggs (10%) did not differ significantly from that of non-stored ones (5%). 6. The extreme lower and upper limits of infection rate estimated for artificially incubated Greater Rhea eggs were 4% and 40%, respectively, being higher than in poultry species. 7. It is concluded that collecting eggs soon after laying will reduce the risk of microbial contamination.

Animals↗
PubMed2006

Effects of beak trimming and cage design on laying hen performance and egg quality.

1. Conventional cages are to be replaced by furnished cages or aviary systems to improve the welfare of hens. We compared the performance and egg quality of hens reared in two designs of furnished cages and of two standard cages. We also explored the consequences of the absence of beak trimming when using these designs. 2. Hens (2028) were housed from 18 to 70 weeks of age in 108 standard cages at 6 per cage (60 cmx63.5 cm), in 96 cages at 5 per cage (59.5 cmx55.5 cm) or in two designs of furnished cage at 15 per cage (24 F15M cages and 36 F15P cages made by two manufacturers) which contained equipment varying in size and location (nests, dust baths and perches). Half of the hens were beak-trimmed in each design. 3. Mortality was low in beak-trimmed hens (<5%) but was unacceptably high in non-beak-trimmed hens due to cannibalism (>40%, 516 hens). Mortality was worse in standard cages than in furnished cages. Consequently, hen-housed egg production was significantly lowered in non-beak-trimmed hens. 4. Egg laying in beak-trimmed hens reared in furnished cages occurred mainly in the nest (80 and 84.8% in F15M and F15P) but also in the dust bath (13.3 and 9.4% in F15M and F15P) and in other parts of the cage (6.7 and 5.8% in F15M and F15P). 5. The total percentage of broken (visual observation) and hair-cracked eggs (candling) was high in the furnished cage designs (15.4 and 19.6% in F15M and F15P, respectively) compared with standard cage designs (8.1 and 12.2% in S6 and S5). This was mainly due to hair-cracked eggs, the highest percentages occurring in the nests, especially in the design with a narrow nest and no egg saver (11.1% in F15M compared to 17.6% in F15P) as a consequence of egg accumulation in the cradle and relatively low frequency of manual egg collection. 6. Eggshell quality (index and breaking strength) was only slightly influenced by cage effects so differences in egg breakage were attributable to impacts related to cage design. 7. It is concluded that beak trimming remains the most effective way to prevent cannibalism, although furnished cages with a large group of hens slightly reduced the incidence, and that further development and optimisation of furnished cages is needed to reach egg quality similar to standard cages.

Animal Husbandry↗
PubMed2006

Comparison of eggshell hygiene in two housing systems: standard and furnished cages.

1. The hygienic properties of eggs produced in two designs of furnished cage were investigated and compared to two standard cage designs. 2. At 28, 37, 47 and 58 weeks of age, the proportion of dirty eggs was higher in one of the furnished cage designs while, in the other, it was similar to standard cages. 3. At 27, 33 and 60 weeks, the bacterial load on the eggshell (total aerobic bacteria and enterococci) was higher in furnished cage designs. A seasonal effect was observed with lower counts at 60 weeks (winter) than at 27 weeks (summer). 4. More dirty eggs and a higher bacterial load were observed in eggs laid outside the nests, which suggests egg hygiene in furnished cages could be similar to standard cages if the equipment in furnished cages was improved to enhance nest laying.

Aging↗
PubMed1975

The fine structure of the pores in the shell of the hen's egg.

No fibrous or crystalline material was present in the lumen of pore canals which were exposed by radial fracture and examined with a scanning electron microscope. The walls of the canals were rough, but they did not have a characteristic ultrastructure. The campanulate outer orifice of the pores was plugged with cuticle in which radial cracks formed channels through which the respiratory gases presumably diffuse.

Animals↗