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PubMed2002

Chromium supplementation can alleviate negative effects of heat stress on egg production, egg quality and some serum metabolites of laying Japanese quail.

This study was conducted to determine the effects of Cr (chromium picolinate, CrPic) supplementation at various levels (0, 200, 400, 800 or 1200 microg/kg of diet) on egg production, egg quality and serum concentrations of insulin, corticosterone and glucose in laying Japanese quail (Coturnix coturnix japanica) reared under conditions of heat stress (32.5 degrees C). Laying Japanese quail (n = 150; 45 d old) were divided into five groups of 30 birds. The quail were fed either a control diet containing 965 microg Cr/kg diet or the control diet supplemented with 200, 400, 800 or 1200 microg of Cr/kg diet. Increased supplemental chromium increased body weight (P = 0.05, linear), feed intake (P = 0.05, linear), egg production (P = 0.01, linear) and also improved feed efficiency (P = 0.01, linear). Increased supplemental chromium linearly increased egg weight (P = 0.01), eggshell thickness, egg specific gravity (P = 0.05) and Haugh unit (P = 0.01). Serum insulin concentration increased linearly (P = 0.01), whereas corticosterone and glucose concentration decreased linearly (P = 0.05) as dietary chromium increased. The best results were obtained with 1200 microg Cr/kg diet, and chromium supplementation at such a level can be considered to be protective management practice in a quail diet, reducing the negative effects of heat stress.

Animals↗
PubMedDate not supplied

New findings in the stumpy-limb mutation of Japanese quail.

The stumpy-limb (SL) mutant (sl/sl) of Japanese quail (Coturnix japonica) is characterized by brachycephaly, parrot-like beaks with mild expressivity, and short and thick limbs. Although this mutant had been believed to be completely embryonic lethal just before hatching, this study revealed that the SL mutant was partly viable when genetic background was altered. A total of 132 of 237 SL embryos (56%) hatched from the eggshell with no assistance; subsequently, 36 of the 132 SL chicks that hatched survived to adulthood. Among these 36 birds, 12 males and four females developed sexually, and of these, six males and four females produced offspring. Mating experiments with the fertile SL mutants and controls confirmed that this mutation is controlled by an autosomal recessive gene. In micromelic or chondrodystrophic mutations of poultry, the SL mutation is an extremely rare instance in which some individuals of both sexes reach sexual maturity and are actually fertile.

Animals↗
PubMed1997

Layer performance of four strains of Leghorn pullets subjected to various rearing programs.

Two experiments were conducted using four strains of Leghorn pullets, namely Babcock, DeKalb, H & N, and Shaver. Pullets were grown on conventional or low protein diets fortified with additional amino acids. At 18 wk of age, 64 pullets from each strain and diet treatment were transferred to individual laying cages, using eight replicate groups of four adjacently caged birds. In a second experiment, pullets from the four strains were selected based on body weight at 18 wk of age (approximately 1,270 vs 1,650 g). Each weight group and strain was again represented by eight replicate groups of four birds. In Experiment 1, there were no strain or rearing diet effects on egg production (P > 0.05). Rearing diet had little long-term effect on any adult characteristics. There were significant (P < 0.01) strain effects on body weight, feed intake, and egg weight, although these were independent of rearing diet. In Experiment 2, regardless of bird strain, the pullets with smaller body weight matured more slowly (P < 0.01) and produced less total egg mass to 70 wk age (P < 0.05). These smaller birds ate less feed and produced smaller eggs (P < 0.01). There were strain effects, independent of 18-wk body weight, for egg weight and eggshell quality (P < 0.01). It is concluded that minor strain differences exist with respect to response to juvenile nutrition, although such effects are only evident in early lay. All strains of bird remain small, 18-wk body weight is reduced, and these birds subsequently eat less feed and produce smaller eggs.

Aging↗
PubMed1997

Effect of lead ingestion on concentrations of lead in tissues and eggs of laying Tsaiya ducks in Taiwan.

This experiment was conducted to investigate Pb concentrations in soft tissues and eggs from laying Tsaiya ducks (Anas platyrhynchos var. domestica), dosed via gelatin capsule with 10 or 20 mg Pb/kg BW daily for 3 mo. Body weights of ducks were not influenced by Pb treatment. In addition, no clinical syndromes involving Pb intoxication were found throughout the experiment. The two levels of Pb consistently resulted in increases in the Pb content of blood, kidney, liver, and gizzard, whereas only 20 mg Pb/kg BW per d of dose additionally increased the Pb in femoral muscle. More Pb was deposited in the kidney and liver after Pb exposure than in the gizzard or femoral muscle. Lead residues in yolk and eggshell from Pb-dosed ducks were significantly higher than in controls; however, Pb in albumen was generally low and was not influenced by Pb treatment.

Administration, Oral↗
PubMed1997

Egg handling and storage.

The temperature and relative humidity of storage, as well as the gaseous environment, interact with the fertile egg over time during storage in such a way as to affect the success of incubation either negatively or positively. This interaction occurs both above and below the "physiological zero", at which embryonic metabolism is minimal. This interaction below physiological zero implies that certain physical aspects of the egg must be affected by the environmental conditions. As the eggshell is a relatively fixed component, changes in albumen, shell membranes, cuticle, yolk, or embryo proper must account for these time- and environment-related effects. It is concluded that the major contributor is the albumen, as it is obviously the most dynamic component below physiological zero and is strategically positioned.

Animals↗
PubMed1997

A problem with characteristics of the thin albumen in laying hens.

Industry observations indicate that a proportion of shell eggs exhibit an uncharacteristic spreading of the thin albumen when they are broken-out for fast-food preparation. Because the height and characteristics of the thick albumen are unaffected, the eggs are classified as Grade A. Preliminary observations discounted effects of egg storage or contaminated feed. Two experiments were conducted with Leghorn hens over a full laying cycle, and involved different levels of protein (14, 16, 18, or 20%) and associated amino acids, or different degrees of acid-base balance (150, 200, 250, or 300 mEq/kg). In each trial, treatments were represented by eight replicate groups of four adjacently and individually caged birds. Diet treatment had some effects on conventional production parameters, although there were no major effects on the area of the thin albumen produced when eggs were broken out. In Experiment 1, birds fed the highest level of protein produced eggs with the smallest thin albumen area; however, there was considerable bird to bird variation with thin albumen area varying from 69 to 122 cm2. Ten birds with compact (x 69 cm2) and 10 birds with spreading thin albumen (x 112 cm2) were inseminated with semen from a single, unrelated rooster. Offspring from these hens had significantly (P < 0.01) different thin albumen characteristics corresponding to those of their dams. Offspring producing eggs with the spreading thin albumen had the thickest eggshells as assessed by deformation measurement (P < 0.05). It is proposed that the excessively large spreading thin albumen area is caused by eggs spending more time in the shell gland.

Acid-Base Equilibrium↗
PubMed1997

Effects of an oxygen-enriched environment on the survival of turkey embryos between twenty-five and twenty-eight days of age.

The hypothesis was tested that increased partial pressure of oxygen during the plateau (25 to 26 d of incubation for turkeys) and paranatal (27 to 28 d of incubation) stages of incubation may increase survival rates of turkeys from selected genetic lines. Partial pressure of oxygen inside the incubator cabinet was increased to 171 + 3 mm Hg of the barometric pressure during the plateau stage in oxygen consumption and compared to ambient oxygen (152 + 3 mm Hg). Turkey embryos from genetic lines selected for egg production (E) or growth (F) were compared to their respective randombred controls. These genetic lines have previously been shown to differ in egg weight, eggshell conductance, length of incubation period, embryonic gluconeogenesis, and survival rates during late incubation. Blood, liver, heart, and pipping muscle samples were obtained prior to pipping, at internal pipping and external pipping, and at hatching. The blood was analyzed for glucose concentration and the remaining tissues were assayed for glycogen concentrations. Survival rates were determined on approximately 2,200 eggs in each of three independent trials of the experiment. Interactions of oxygen treatment and genetic line were observed for embryonic survival, heart growth, and hepatic glycogen content. The data suggest that the response to increased oxygen tension in selected genetic lines has been diminished. It was concluded that embryos have been altered metabolically by genetic selection and the concomitant increase in mortality of selected lines during the plateau and paranatal stages is not simply the result of shell quality and hypoxia.

Aging↗
PubMed1998

The effects of enzyme and inorganic phosphorus supplements in wheat- and rye-based diets on laying hen performance, energy, and phosphorus availability.

A total of 640 22-wk-old pullets (Shaver SX 288) housed four birds per cage in 40 experimental units (four cages per unit), were randomly assigned eight experimental diets in a 2 x 2 x 2 factorial arrangement. The treatments consisting of two grain sources (wheat and rye) two levels each of crude enzyme preparation (0 and 0.1% Roxazyme G), and added inorganic phosphorus (0 and 0.105%) were fed for five 4-wk periods. At 42 wk of age, 40 individually caged layers were fed the experimental diets with 0.3% chromic oxide (5 individual birds per treatment) to determine AMEn and available P. Plasma P and Ca were also determined. Egg production, feed intake (FI), egg weight, feed efficiency (FE), and specific gravity of eggs were significantly (P < or = 0.05) affected by the experimental periods. Hens fed wheat-based diets had higher (P < or = 0.05) tibia ash (54.3 vs 52.5%), excreta dry matter (22.0 vs 17.7%), and eggshells with > or = 1.080 specific gravity (93.5 vs 89.9%) than birds fed rye. Enzyme supplementation significantly improved AMEn (P < or = 0.01) and FE by 6.2 and 3%, respectively. Egg production increased numerically from 87.6 to 90.1%. Inorganic P supplementation significantly increased egg production (P < or = 0.01), FI, FE, and AMEn (P < or = 0.05) by 4.4, 2, 3, and 2.8%, respectively, but significantly (P < or = 0.05) decreased the proportion of eggs having a specific gravity > or = 1.080 from 92.8 to 90.6%. The enzyme and inorganic P supplementation had no effect on tibia ash content and total plasma Ca and P. Rye can be used in layer rations yielding satisfactory performance when fed with a fungal crude enzyme preparation high in pentosanase/xylanase activity.

Animal Feed↗
PubMed1998

Influence of supplemental phytase on calcium and phosphorus utilization in laying hens.

A 6-wk study was conducted to determine the influence of supplemental phytase on Ca and P utilization in commercial laying hens. Diets were arranged factorially with three levels of dietary Ca (2.5, 2.8, and 3.1%), fed at two levels of nonphytate P (0.1 and 0.3% NPP) with and without supplemental phytase. Each diet was replicated eight times, with 16 hens per replicate. Criteria evaluated included egg specific gravity, feed consumption, egg production, egg weight, eggshell weight, bone quality, and body weight. Increasing dietary Ca significantly improved shell quality within 1 wk. A significant improvement in shell quality due to phytase supplementation was also observed during the 1st wk. Increasing NPP from 0.1 to 0.3% had not effect on egg specific gravity until Week 3, suggesting that the phytase benefit during Weeks 1 and 2 was related to improved Ca utilization. From Weeks 3 to 6, a significant P by phytase interaction was observed in which the magnitude of shell quality improvement was greatest when the 0.1% NPP diet was supplemented with phytase. This interaction was also observed from Weeks 3 to 6 for feed consumption and egg production and during Weeks 4 and 6 for egg weights. Phytase supplementation completely overcame the adverse effects associated with low dietary P and significantly reduced the impact of low dietary Ca on hen performance.

6-Phytase↗
PubMed1999

Influence of supplemental microbial phytase on first cycle laying hens fed phosphorus-deficient diets from day one of age.

Pullets (19 wk of age) previously fed varying levels of aP (available P) with and without phytase (Natuphos) from Day 1 of age were used to determine the influence of 300 FTU phytase/kg diet on hen performance during Phase 1 (Week 21 to 36) and 2 (Week 37 to 48). At 19 wk of age, pullets were switched from developer diets to layer diets. The aP levels used in this portion of the study remained at 0.1, 0.2, 0.3, and 0.4% with and without phytase. These were the same levels fed in the starter and developer diets. Feed consumption, egg production, egg weight, egg specific gravity, and mortality were the criteria used. Reduction of aP from 0.4 to 0.2% had no effect on feed intake, egg production, egg weight, or eggshell quality (P > 0.05). However, hens fed 0.1% aP showed reduced feed intake, egg production, and bone mineral density (P < 0.001) and increased mortality (P < 0.001), but 300 FTU/kg phytase supplementation completely prevented these deficiencies. Eggs from hens fed 0.2, 0.3 and 0.4% aP diets were heavier than those fed 0.1% aP. Interactions between aP and phytase for feed consumption (P < 0.003), egg production (P < 0.001), and egg weight (P < 0.04) indicated that phytase corrected all deficiency symptoms in hens consuming 0.1% aP but showed no influence on hens fed aP levels > 0.2%. During Phase 2, aP by phytase interactions for feed consumption and egg production demonstrated that dietary phytase-corrected reductions related to P deficiency in hens consuming 0.2% aP. Results indicate that the addition of phytase in pullet diets from Day 1 of age through the first lay cycle can prevent reductions in performance of pullets fed low P diets.

6-Phytase↗
PubMed1999

Effect of supplemental oxygen on blood plasma organic acids within embryos from selected lines of turkeys.

The hypothesis was tested that increased oxygen tensions during the plateau stage of oxygen consumption (25 and 26 d of incubation) would cause different metabolic responses from embryos selected for increased egg production or growth. Embryos were exposed to 171 or 152 mm Hg partial pressure of oxygen from 25 to 28 d of incubation, a time when the oxygen conductance properties of the eggshell are exceeded by the embryonic tissue demands for oxygen. Carbohydrate and lipid metabolism were observed by measuring plasma organic acids in embryos from selected lines and randombred controls. (E was selected for increased egg production; RBC1 is the randombred line from which it was selected. F was selected for increased BW; RBC2 is the randombred line from which it was selected.) During the plateau stage in oxygen consumption, RBC2 embryos responded to added oxygen by utilizing fat rather than carbohydrate, whereas F embryos responded by using less fat as well as less carbohydrate from the liver and kidney. The response of F embryos to added oxygen is the opposite that might be expected for aerobic metabolism. The reason that selection for growth has resulted in such a metabolism is unknown. The E embryos displayed depressed lactate and beta-hydroxybutyrate levels, but plasma urates were elevated compared with RBC1, suggesting that the selection for egg production has also resulted in a unique metabolism. The embryonic processes described in the current study suggest that selected embryos are unable to respond to elevated partial pressure of oxygen by adjusting energy metabolism, which may result in increased embryonic mortality during this stage.

3-Hydroxybutyric Acid↗
PubMed1999

Comparison of egg hatchability and in vitro survival of goose embryos of various origins.

Hatchability of 69,324 fertilized eggs of White Italian geese from the WD1 maternal strain, selected for egg production, and of 25,226 eggs from the WD3 paternal strain, selected for weight gain, were compared. A significant difference was noted, but its magnitude varied during the reproduction season. Mean results for the WD1 strain (80.9%) were always higher (P < 0.01) than those of WD3 strain (75.8%). To determine the causes of this difference, goose eggs from WD1, WD3, and the Kuban (K) strain that demonstrate high reproductive performance (egg number, fertility, and hatchability) were incubated in a laboratory scale incubator. Embryonic mortality and egg weight loss during incubation were determined. Best hatchability (78.5%) was noted in eggs from K goose strain and the weight loss attained 10.9% of the initial egg weight, until Day 25 of incubation. With the higher egg weight loss in Strains WD1 (11.8%) and WD3 (13.2%), hatchability was diminished to 67.3 and 65.5%, respectively. Better hatchability resulted from lower mortality up to Day 6 of incubation and, especially, between Days 7 and 25 of incubation. The differences found in the egg weight losses and in embryonic mortality suggest a need for adjusting the incubation technique to the particular goose genotype. Embryo cultivation in vitro in plastic containers made the comparison of embryo survival possible, because the interaction of incubator microclimate by eggshell quality was eliminated. The results noted due to strain were ranked in the following order: K, WD1, and WD3. The experimental findings suggest that, apart from that of shell quality effect on various egg weight losses during incubation, there appear to be other factors that cause differences in hatchability of the goose strains studied.

Animals↗
PubMed2000

The effect of storage and strain of hen on egg quality.

Eggs from 31-wk-old ISA-White and ISA-Brown hens were sampled immediately after lay and after periods of storage of 1, 3, 5, and 10 d at room temperature. Longer periods of storage resulted in lower albumen weight and albumen height and higher albumen pH. Eggs from ISA-Brown hens had more albumen and shell than those from ISA-White hens, likely due to differences in selection history rather than due to pleiotropic effects of eggshell color. Within each line and storage period, the egg weight was more closely associated with albumen weight than with yolk or shell weight. The albumen height of eggs from ISA-Brown hens was lower than that of ISA-White hens at all storage times, but the albumen pH was not affected by the strain. Albumen height and albumen pH were statistically unrelated in fresh eggs, but the association became larger as the storage period increased, suggesting that albumen height measures factors that are present when the egg is laid and changes during storage, whereas albumen pH measures only the effect of storage.

Animals↗
PubMed2000

Correlation of body weight with hatchling blood glucose concentration and its relationship to embryonic survival.

The negative correlation between selection for rapid growth and embryonic survival was investigated. Embryonic growth was assessed with hatchling weights of a closed population of commercial turkey breeders. Hatchling weights were highly significantly (P < 0.0001) and positively correlated with blood glucose concentrations at hatching. This relationship existed for both tom and hen poults. Significant differences among dams for hatchling blood glucose were observed. Further experiments examined dams selected for producing poults hatching with high (High) or low (Low) blood glucose concentrations. The High embryos were in larger-sized eggs with the same eggshell conductance but with significantly lower conductance constants than the Low embryos, suggesting that Low had longer incubation periods. High embryos grew faster than Low embryos with elevated organ glycogen concentrations. Organic acid analysis indicated elevated plasma alpha-ketoglutarate, urate, and beta-hydroxy butyrate concentrations, suggesting a greater reliance on gluconeogenesis for the High group. Posthatch growth was significantly positively correlated with hatchling blood glucose concentrations in toms but not in hens. Tom poults hatching with elevated glucose were heavier than low glucose hatch mates until 22 wk of age, but hen poults displayed no differences until 16 wk when High hens weighed less than Low hens. These data suggest that the negative correlation between rapid growth and embryonic survival is related to egg-shell conductance constants and embryonic energy metabolism.

3-Hydroxybutyric Acid↗
PubMed2000

Preventive effect of partially hydrolyzed guar gum on infection of Salmonella enteritidis in young and laying hens.

The preventive effect of partially hydrolyzed guar gum (PHGG) on the colonization of Salmonella enteritidis (SE) in young and laying hens was investigated. The effects of feed supplemented with 0.025, 0.05, and 0.1% PHGG was examined on young hens orally infected with SE. The incidence of SE in organs was decreased, the excretion of SE into feces was increased, and the agglutinating antibody titer to SE in serum was decreased by the administration of PHGG to young hens. In particular, feed supplemented with 0.025% PHGG was the most effective. It was also shown that feed supplemented with 0.025% PHGG increased the number of Bifidobacterium spp. and Lactobacillus spp., the most numerous intestinal bacteria in the cecum of young hen. The effect of the excretion of SE via feces was also observed in an experiment using laying hens. The incidence of SE on the surface of the eggshell and in egg white and egg yolk was also decreased when the feed of laying hens was supplemented with 0.025% PHGG. These results show that the administration of feed supplemented with PHGG can prevent the colonization of SE in young and laying hens, which, in turn, could be related to improvement in the balance of intestinal microflora.

Agglutination Tests↗
PubMed2001

Optimum site for in ovo amino acid injection in broiler breeder eggs.

Three experiments were conducted to evaluate the effect of differences in in ovo amino acid (AA) injection sites in broiler breeder eggs on subsequent hatchability and BW of chicks. In Experiment 1, an AA solution was injected into eggs with 13-mm or 19-mm, 27-ga needles. Uninjected eggs served as controls. Hatchability was decreased (P < 0.05) in eggs receiving AA injections with the 19-mm needle in comparison to the control and 13-mm-injected groups. However, BW of chicks increased (P < 0.05) relative to pre-incubational egg weight by AA injection with the 13-mm needle. In order to evaluate the in ovo location of AA injections from Experiment 1, India ink was injected into eggs in Experiment 2 with a 13-or 19-mm needle. Immediately after injection, the air cell end of the egg was windowed in order to observe effects of injection site. Windowing of eggs was accomplished by removing a piece of the eggshell over the air cell and the underlying membrane at Day 7 of incubation. The amount of injected India ink was higher in the extra-embryonic coelom in eggs treated by both needles. However, the occurrence of India ink in the extra embryonic coelom was higher (P < 0.05) in the group injected with AA solution using a 13-mm needle as compared to that after injection using a 19-mm needle. The observation of India ink in the amniotic cavity was higher (P < 0.05) in the group injected with AA solution using a 19-mm needle rather than that using a 13-mm needle. In Experiment 3, treatments consisted of control (uninjected eggs) or windowed eggs. Windowed eggs received AA to the chorioallantoic membrane, the yolk, extra-embryonic coelom, or amniotic cavity at Day 7 of incubation. Hatchability was reduced, but chicks hatched when eggs were windowed and when AA were injected into the yolk sac or extra-embryonic coelom. However, chicks did not hatch when AA were administered to the chorioallantoic membrane or into the amniotic cavity. These results suggest that the best AA injection sites in ovo may be the yolk and extra-embryonic coelom.

Amino Acids↗
PubMed2002

Environmental incubation factors influence embryonic thyroid hormones.

Thyroid hormone responses in embryonic avian species are of two types, developmental and metabolic. Many studies have characterized the developmental function of the turkey embryonic thyroid, but few have characterized the metabolic function. Therefore, the purpose of this study was to describe the response of turkey embryonic thyroid hormones to three environmental factors. We proposed that embryonic thyroids from different genetic backgrounds would respond differently to changes in maternal diet and incubation temperature. Lines of turkeys known to have different embryonic growth and survival were examined in the current study. These eggs differ in egg weight, eggshell conductance, hatchling weight and organ maturity at the time of hatching. Eggs were produced throughout a 20 wk laying period and embryos were sampled at monthly intervals. Half of the hens producing the eggs were fed additional iodide in their diets, then, subsequently, half of each dietary treatment and line combination were incubated at either 36.8 C or 37.5 C to prolong the incubation period. Embryos were sampled during the final week of incubation when thyroid hormones become elevated to effect maturation and survival functions in turkey embryos. Embryonic thyroxine (T4) and triiodothyronine (T3) levels were assayed by RIA and compared among the treatments. Line, diet, and incubation period interacted to affect the levels of T4, T3 and T3 to T4 ratios in the turkey embryonic during late incubation. It was concluded that environmental factors can affect circulating thyroid hormone levels in turkey embryos, thus affecting metabolic functions, and the possibility exists to manipulate these circulating levels using environmental incubation conditions to improve hatchability.

Animal Feed↗
PubMed2002

Localization of the fertilized germinal disc in the chicken egg before incubation.

At the time of oviposition, the embryo in the fertilized chicken egg has developed the germinal disc on top of the yolk and contains thousands of blastodermal cells. The germinal disc escapes exact localization because it is surrounded by albumen and shell membranes under a calcified shell. This study investigated whether or not ultrasonography or nuclear magnetic resonance imaging (MRI) are suited to localize the germinal disc and, if so, to estimate the accuracy of localization. Hatchability of treated eggs was also recorded. The ultrasound waves were reflected by the shell. The germinal disc could be seen only after removal of the eggshell and the outer shell membrane. In all, 39 intact eggs, MRI localized the germinal disc within 2 mm thick image slices. The mean position of the germinal disc deviated 3.0+/-2.1 mm from the maximum vertical plane of the egg with a mean distance to the inner surface of the shell of 2.7+/-1.1 mm. Incubation resulted in 84.2 and 77.5% hatched chicks for imaged eggs and controls, respectively. The localization results of MRI were verified manually in 38 open shell cultures. Correlation coefficients for the position of the germinal disc were r = 0.86 to 0.99 for the x-axis, r = 0.75 to 0.89 for the y-axis, and r = 0.63 to 0.76 for the z-axis. The study thus shows that MRI is a reliable tool to localize the germinal disc within the intact freshly laid egg.

Animals↗