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PubMed1983

Autoradiographic demonstration of the penetration of albumen-derived material through the vitelline membrane into the egg yolk, exterior to the avian blastoderm.

A method enabling in ovo transplantation and cultivation of fertilized, unincubated quail yolks is described. By this technique, nonradioactive yolks were transferred into nonradioactive egg shells filled with in vivo radioactively labeled albumen. With autoradiography it was demonstrated that during early avian blastoderm development, albumen-derived material can penetrate through the vitelline membrane of the acellular rimzone distal to the margin of over-growth.

Animals↗
PubMed1981

Effect of dietary zearalenone on reproduction of chickens.

Variable quantities of zearalenone (0, 10, 25, 50, 100, 200, 400, or 800 mg/kg diet) were incorporated into a practical laying hen diet and fed to 30-week-old White Leghorn females in egg production. During the 3 week pretest and 8 week experimental periods hens were inseminated weekly with .05 ml of pooled semen from males fed normal diets. Zearalenone was without effect on egg production, egg size, feed consumption, change in body weight, fertility, hatchability of fertile eggs, growth of progeny to 3 weeks of age, comb, weight, oviduct weight, heart weight, liver weight, spleen weight, egg shell thickness, Haugh units, blood hematology, serum calcium, serum inorganic phosphorus, and serum alkaline phosphatase. Zearalenone above 50 mg/kg of diet caused reduced serum cholesterol. In a reciprocal study, adult male New Hampshire chickens were fed diets containing 0, 100, or 800 mg/kg zearalenone for an 8 week period. Semen was collected and inseminated into White Leghorn females fed normal diets. Zearalenone was without effect on fertility or hatch of fertile eggs resulting from matings of these males. Zearalenone resulted in reduced serum inorganic phosphorus, serum cholesterol, and serum alkaline phosphatase in males. Histological examination of a number of tissues in both males and females revealed no changes due to zearalenone feeding. It is concluded that zearalenone up to 800 mg/kg of diet is without effect on reproductive performance of mature chickens.

Animal Feed↗
PubMed2006

Cloning of ovocalyxin-36, a novel chicken eggshell protein related to lipopolysaccharide-binding proteins, bactericidal permeability-increasing proteins, and plunc family proteins.

The avian eggshell is a composite biomaterial composed of noncalcifying eggshell membranes and the overlying calcified shell matrix. The shell is deposited in a uterine fluid where the concentration of different protein species varies at different stages of its formation. The role of avian eggshell proteins during shell formation remains poorly understood, and we have sought to identify and characterize the individual components in order to gain insight into their function during elaboration of the eggshell. In this study, we have used direct sequencing, immunochemistry, expression screening, and EST data base mining to clone and characterize a 1995-bp full-length cDNA sequence corresponding to a novel chicken eggshell protein that we have named Ovocalyxin-36 (OCX-36). Ovocalyxin-36 protein was only detected in the regions of the oviduct where egg-shell formation takes place; uterine OCX-36 message was strongly up-regulated during eggshell calcification. OCX-36 localized to the calcified eggshell predominantly in the inner part of the shell, and to the shell membranes. BlastN data base searching indicates that there is no mammalian version of OCX-36; however, the protein sequence is 20-25% homologous to proteins associated with the innate immune response as follows: lipopolysaccharide-binding proteins, bactericidal permeability-increasing proteins, and Plunc family proteins. Moreover, the genomic organization of these proteins and OCX-36 appears to be highly conserved. These observations suggest that OCX-36 is a novel and specific chicken eggshell protein related to the superfamily of lipopolysaccharide-binding proteins/bactericidal permeability-increasing proteins and Plunc proteins. OCX-36 may therefore participate in natural defense mechanisms that keep the egg free of pathogens.

Acute-Phase Proteins↗
PubMed2006

Identification of eggshell membrane proteins and purification of ovotransferrin and beta-NAGase from hen egg white.

Exposure of selected Gram-positive and Gram-negative bacterial pathogens to egg shell membranes (ESM) significantly reduced their thermal resistance and/or inactivated cells. Although the components responsible for this antibacterial activity have not been conclusively identified, several proteins associated with the ESM activity have been identified including beta-N-acetylglucosaminidase, lysozyme and ovotransferrin, with each displaying varying degrees of antibacterial activity. Numerous attempts to purify active fractions of beta-N-acetylglucosaminidase, lysozyme and ovotransferrin from the ESM proved somewhat limited; however, hen egg white (HEW) beta-N-acetylglucosaminidase was purified using a two-step chromatographic procedure, isoelectric focusing followed by cation exchange chromatography. Pure fractions of ovotransferrin were also obtained in the process. SDS-PAGE electrophoresis and Matrix-Assisted Laser Desorption Time-of-Flight Mass Spectrometry were then used to partially characterize the individual protein components. Purified protein fractions such as these will be required in order to fully elucidate the mechanism responsible for the antimicrobial properties associated with the ESM.

Acetylglucosaminidase↗
PubMed2003

Effect of enzyme addition to wheat-, barley- and rye-based diets on nutrient digestibility and performance of laying hens.

1. Laying hen performance, egg quality, intestinal viscosity and nutrient apparent digestibility were evaluated with respect to the main cereal used in the diet and dosage rate of a fungal beta-glucanase/xylanase enzyme complex. 2. Twelve diets were arranged factorially, with three soluble fibre cereals (SFC); 500 g/kg of wheat or barley or 350 g/kg of rye, and 4 enzyme concentrations (0, 250, 1250 and 2500 mg/kg). An additional control diet based on maize was also included. 3. The use of SFC in the diet instead of maize did not affect egg production or food efficiency, but hens fed on SFC diets exhibited a higher incidence of dirty eggs than hens fed on the maize diet (8-6 vs 4.6%; P<0.01). 4. Laying hens fed on enzyme-supplemented diets produced more eggs (2.1%; P<0.05) and had better food efficiency per dozen eggs (2.5%; P<005) than hens fed on non-supplemented diets. An excess of enzymes in the diet (10 times the recommended dose) did not produce any deleterious effect on laying hen productivity. 5. Enzyme supplementation (ES) reduced intestinal viscosity (P<0.001) and the incidence of dirty eggs (P<0.01). The reduction in viscosity was more pronounced in barley than in wheat or rye diets (P<0.05). 6. Apparent nutrient digestibility in SFC diets was higher with ES, including dry matter (3.1%; P=0.08), fat (4.4%; P<0.001), non-starch polysaccharides (83.3%; P<0.01) and AMEn (2.5%, P<0.01). 7. It is concluded that substitution of maize by SFC is facilitated by ES, especially with respect to egg production, food conversion efficiency and egg shell cleanliness. An excess of enzymes did not produce any deleterious effect on nutrient digestibility or performance of laying hens.

Animal Feed↗
PubMed1993

Egg-related Salmonella enteritidis, Italy, 1991.

In recent years, Salmonella enteritidis has become an increasingly important public health problem in Italy. In some parts of the country, the fraction of total human salmonella isolates accounted for by S. enteritidis has risen from 3-4% in the mid-1980s to more than 30% in 1990. Between 1990 and 1991, the number of reported S. enteritidis outbreaks increased more than sixfold. The 33 outbreaks reported in 1991 occurred in seven contiguous regions in northern and central Italy and were clustered in time between June and October: in the majority, products containing raw or undercooked shell eggs were implicated. Five of the egg-related outbreaks that occurred within a 30 kilometre radius over a 7-week period were investigated in detail. A phage type 1 strain containing a 38.9 MDa plasmid appeared responsible for three of the outbreaks, while in the remaining two a phage type 4 strain, also with a 38.9 MDa plasmid was isolated. Efforts are being made to enhance epidemiological surveillance and laboratory evaluation, and the use of pasteurized eggs has been recommended for high-risk populations.

Disease Outbreaks↗
PubMed1978

Intrauterine development of the microfilariae of Dipetalonema viteae.

The egg shell of Dipetalonema viteae separated from the oolemma and became highly convoluted at an early stage of development. No second oolemma or trilaminate membrane was seen. Channels containing electron dense material (thought to be nutrient material from the uterine wall) were formed between adjacent embryos. Many developing embryos died. Microvilli were formed by the uterine wall and developing embryos were closely apposed to these (again presumably to obtain nutrient). Embryos emerged from the egg in the uterus and were born as unsheathed microfilariae.

Animals↗
PubMed1997

Outbreak of Salmonella enteritidis phage type 6 infection associated with food items provided at a buffet meal.

Preliminary enquiries following prompt notification of three cases of suspected food poisoning revealed that they had all attended the same three functions during the preceding weekend. Subsequent investigation identified 49 people with gastrointestinal symptoms, 13 of whom were infected with Salmonella enteritidis phage type 6. Forty-five of those with symptoms, including 11 with confirmed infection, had eaten a buffet meal at a public house. Eating egg sandwiches was strongly associated with infection. Defects in the kitchen structure and the storage and handling of the implicated food items provided the potential for cross contamination. Salmonella was isolated from several environmental sites, including a general purpose cleaning cloth. Two different quiches and pork pies, which were possible vehicles of infection were thought to have been contaminated after being brought into the kitchen. The investigation did not reveal whether or not shell eggs used in the sandwiches were the original source or whether they too had been contaminated during their preparation.

Disease Outbreaks↗
PubMed1986

Effects of feeding hens a high level of vomitoxin-contaminated corn on performance and tissue residues.

A balance experiment was conducted with hens fed a high level of vomitoxin (V) to study the effect on live performance, egg quality, and tissue residues of V. Twenty Single Comb White Leghorn (SCWL) hens, approximately 26 weeks of age, were individually housed in metabolic cages and fed a control (C) or V (82.8 mg/kg) diet for 27 days. No significant differences were observed in feed consumption, body weight gain, egg production, egg weight, haugh units, shell deformation, or egg shell thickness between treatments. No gross pathological lesions were observed in the oral cavity, proventriculus, small or large intestine, liver, spleen, heart, or kidney. Small erosions were present in the gizzard mucosa of birds fed the V-diet. No significant V residues were found in the yolk, albumen, egg shell, liver, kidney, thigh, or breast muscle, but levels of approximately 20 ppb were found in the gizzard. About 4.2% of the total V consumed by hens were recovered in the feces.

Animals↗
PubMed1987

Relationship of parents' age, hatching egg weight, and shell quality to day-old chick weight as influenced by oviposition time.

This study was conducted with 840 eggs from commercial breeder hens to determine relationship of parents' age, egg weight, and to oviposition time and shell quality and day-old chick weight. Results indicate that eggs laid in the afternoon were significantly smaller with significantly better shell quality than those laid in the morning (64.1 vs. 64.5 g and specific gravity of 1.077 vs. 1.074, respectively). Also, chicks from afternoon eggs tended to weigh significantly less than those from morning eggs. However, the egg weight: chick weight ratio was not significantly affected by oviposition time; it was the same for morning and afternoon eggs (70.7 vs. 70.1%). The linear relationships between egg weight, age, and chick weight or between egg weight and chick weight were strong (R2 = .78 to .91), but the associations between specific gravity and chick weight were weaker (R2 = .28 to .24). It was possible to use both parents' age and egg weight or egg weight alone to predict chick weight for chicks hatched from morning and afternoon eggs.

Aging↗
PubMed1992

Calcium and phosphorus metabolism and eggshell thickness in laying hens producing thick or thin shells.

Two experiments were carried out to investigate the Ca and P metabolism of hens laying thick- (THK) or thin-shelled (THN) eggs on shell-forming days (SF) and days on which shell formation does not occur (NSF). In Experiment 1, 10 hens identified as producing THK or 10 hens producing THN eggs were offered a diet containing 3.5% Ca and .4% available P. Feed consumption, egg production, egg weight, egg deformation, and shell weight were recorded over 8 days. Shells and excreta were collected daily for Ca and P analysis. Feed, Ca, and P intake did not differ significantly (P greater than 0.5) between the two groups of hens, however, feed intake and Ca retention increased significantly (P less than .05) on SF compared with NSF days. The THK hens retained significantly (P less than .05) more Ca compared with THN hens. No differences (P greater than .05) were recorded for egg production, although there were differences (P less than .05) in egg weight and shell deformation between the two groups of hens. Increased egg weight did not account for differences (P less than .05) in eggshell deformation. Although percentage shell Ca was not significantly different (P greater than .05), total shell Ca was different (P less than .05) between the two groups. In Experiment 2, both groups of birds (THK and THN) were allowed simultaneous access to two different diets, a high-energy, high-protein diet low in Ca and P, and a low-energy, low-protein diet high in Ca and P.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2001

The effects of thermal and hydric environments on hatching success, embryonic use of energy and hatchling traits in a colubrid snake, Elaphe carinata.

We examined the effects of thermal and hydric environments on hatching success, the embryonic use of energy and hatchling traits in a colubrid snake, Elaphe carinata. The eggs were incubated at four temperatures ranging from 24 to 32 degrees C on substrates with water potentials of 0 and -220 kPa using a 4x2 factorial design. Both thermal and hydric environments affected the water exchange between eggs and their surroundings. Eggs incubated in wetter substrates gained mass throughout the course of incubation, whereas eggs in drier substrates gained mass during the first half of incubation and lost mass thereafter. Hatching success was noticeably higher at 26 and 30 degrees C than at 24 and 32 degrees C, but among treatments, differences in hatching success were not significant. Temperature significantly affected the duration of incubation and most hatchling traits examined. Deformed hatchlings were found in all temperature treatments, with more deformities observed at 32 degrees C. Hatchlings from eggs incubated at different temperatures differed in wet body mass, but the differences stemmed mainly from variation in water contents. Embryos at different temperatures completed development at nearly the same expenditure of energy and catabolized nearly the same amount of lipids, but hatchlings from different temperatures differed in the development condition of carcass at hatching. Hatchlings from eggs incubated at 26 degrees C were larger in SVL than those from other higher or lower incubation temperatures, characteristically having larger carcasses; hatchlings from 32 degrees C eggs were smaller in SVL and had smaller carcasses but larger residual yolks than those from lower incubation temperatures. Hatchlings from eggs incubated at 24 degrees C were shorter in tail length but greater in size (SVL)-specific body wet mass than those from higher incubation temperatures. Within the range from -220 to 0 kPa, the substrate water potential did not affect hatching success, the embryonic use of energy and all hatchling traits examined, and the effects of temperature were independent of the effects of substrate water potential. Therefore, our data add evidence showing that embryonic development in reptiles with pliable-shelled eggs is relatively insensitive to variation in hydric environments during incubation.

Animals↗
PubMed1989

Identification, expression and in situ hybridization of an eggshell protein gene from Fasciola hepatica.

The molecular basis of egg formation in the parasitic liver fluke, Fasciola hepatica, was investigated by isolating and characterizing an abundant cDNA from a female genital complex cDNA library. It was expressed in Escherichia coli as a beta-galactosidase fusion protein, which was purified and used to produce polyclonal antibodies. Using immunoblots, the antiserum recognized two soluble constituents of isolated egg shells, both significantly larger than predicted from cDNA sequencing. Using in situ hybridization, the message was detected in cells in the adult vitelline follicles. Eggshell protein mRNA expressed in E. coli will provide a source of precursor protein for further studies of parasite eggshell formation.

Animals↗
PubMed1988

Egg yolk paste for determining some food poisoning bacteria.

Egg yolk, aseptically prepared from fresh eggs, was partially dehydrated with a 40% high fructose corn syrup solution, and 10% salt was added. This salted yolk paste was added to mannitol salt agar for the detection of Staphylococcus aureus, to NaCl-glycine Kim and Goepfert medium for detection of Bacillus cereus, to Clostridium welchii agar for detection of C. perfringens, and to Gifu anaerobic medium for detection of C. botulinum. These food poisoning bacteria showed the same lecithovitellin (LV) reaction on these media as on the same media prepared with fresh egg yolk. The yolk paste could be stored at -20 C without freezing and did not show any bacterial growth after holding at 25 C for 30 days. The increased salt content resulted from the addition of salted yolk paste to the media did not inhibit the growth of the food poisoning bacteria used in these experiments. For the identification of the food poisoning bacteria used in this work, and which give a LV reaction, salted yolk paste is more convenient to use than yolk separated from fresh shell eggs.

Bacillus cereus↗
PubMed1994

Studies on transmission and schistosome interactions in Senegal, Mali and Zambia.

The transmission and interaction of schistosomes in the Senegal River Basin in Mali and Zambia are reviewed and some preliminary field data are presented. In the Senegal River Basin four species of schistosomes are prevalent: Schistosoma mansoni, S. haematobium, S. bovis and S. curassoni as well as the following potential intermediate hosts: Biomphalaria pfeifferi, Bulinus globosus, B. umbilicatus, B. truncatus, B. senegalensis and B. forskalii. The role of each of these species in the transmission of schistosomes in man and domestic stock is discussed. Recent ecological changes caused by the construction of dams at Diama and Mananatali on the Senegal River, such as reduction in salinity, more stable water flow, creation of irrigation canals and development and extension of rice culture, have contributed towards the occurrence of new outbreaks of both intestinal and urinary schistosomiasis in the Senegal River Basin. In Mali, the four main areas of high prevalence of S. haematobium are Office du Niger (irrigation areas), Bandiagara (small dams), Selingué (dam areas) and Baguineda (irrigation areas). Apart from the Office du Niger, S. mansoni infections are rare. Surveys were carried out in the Dogon Country (Bandiagara District) in an attempt to confirm the recent independent reports of the presence of S. intercalatum. Data based on egg morphology and Ziehl Neelsen staining of egg shells suggested the possible occurrence of S. haematobium x S. intercalatum hybrids. Potential factors affecting the focal endemicity of S. haematobium in Mali are discussed.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1998

Gordon Memorial Lecture. A holistic view of poultry science from a reductionist perspective.

1. The success of the poultry industry has been dependent upon development of a precise understanding of poultry biology. 2. The advent of tools and probes that reveal the molecular and cellular organisation of complex physiological systems should be embraced by the poultry industry to gain insights into recurring problems such as egg shell quality and ascites. 3. The ability to modify the genome of chickens provides an opportunity to breed chickens with unprecedented precision. 4. The judicious use of time and resources will require a working knowledge of molecular and cellular biology and the poultry industry. There is an urgent need for educational facilities that provide both perspectives.

Animals↗
PubMed1995

Phosphorus requirements of laying hens fed on wheat-based diets.

1. Three experiments were carried out to determine the phosphorus (P) requirements of laying hens aged 34 to 58 weeks (experiment 1), 59 to 70 weeks (experiment 2) and 22 to 50 weeks (experiment 3) given diets containing wheat, sorghum and soyabean meals as the main ingredients. Dietary total P (Pt) varied between 3.2 and 7.3 g/kg (experiment 1), 3.2 and 4.6 g/kg (experiment 2) and 3.0 and 6.6 g/kg (experiment 3). Hens were housed at either 18 degrees or 30 degrees C (experiments 1 and 2) and uncontrolled temperature (experiment 3), and in experiment 2 diets were fed without or with a phytase supplement of 500 units/g. 2. Dietary Pt had no significant effect on production measures in any experiment. Increases in dietary Pt adversely influenced egg shell quality although uterine calcium (Ca), ATPase and carbonic anhydrase activities were unaffected. 3. A 3-d-feeding trial in experiment 1 gave maximum Pt retentions of 228 mg/d at 18 degrees C and 204 mg/d at 30 degrees C. These were obtained with diets containing, respectively, 4.6 and 6.0 g Pt/kg. 4. Plasma inorganic P (Pi) increased consistently with increases in dietary Pt at all temperatures but plasma total Ca, and tibia Ca and P, were unaffected. 5. The inclusion of the phytase supplement in diets containing 3.2 and 4.6 g Pt/kg had an adverse effect on egg production at both temperatures in experiment 2. 6. A dietary Pt concentration of 3.2 g/kg, providing a calculated 1.2 g available P (Pav)/kg, with a dietary phytase activity of less than 200 units/kg, satisfied the P requirements of the hens used in these studies. However, the data from experiment 3 suggest that the Pt requirement of some flocks fed on wheat-based diets may be lower than 3.2 g/kg.

Animal Feed↗