Eggshell Index Research Articles

Association of Different Body Sizes and Egg Quality Characteristics in White Leghorn Chicken Breed of South Africa

Egg quality could influence the price of the table and hatching eggs. However, the effects of hen’s live body weight on egg characteristics are poorly understood. The present study evaluated the influence of body weight (BW) on egg characteristics, such as egg width (EWD), shell weight (SW), egg length (EL), albumen weight (AW), yolk weight (YW), shell surface index (SI), albumen ratio (AR), shell ratio (SR), and yolk ratio (YR) of White Leghorn chicken. A total of 100 White Leghorn chickens at 30 weeks of age were used in the current study of which 300 eggs were collected. Live body weight was classified into three groups namely, small (≤ 195g), medium (196-220g), and large (≥ 221g). The results revealed that the White Leghorn layer’s live body weight was positively influenced by the eggshell index and egg length. Additionally, the results indicated that body weight did not affect EW, SW, EWD, SR, YW, AW, AR, and YR. In conclusion, the live body weight influences egg length and shell index in the White Leghorn chicken breed.

Transcriptome and histological analyses on the uterus of freckle egg laying hens

BackgroundIn this study, we explored the characteristics and causes of freckle formation. We collected 15 normal and freckled eggs each for eggshell index testing and hypothesized that the structure and function of the uterus would have a direct effect on freckled egg production given that eggshells are formed in the uterus. To test this hypothesis, we collected uterine tissue from laying hens (418 days of age) that laid normal (Group C, n = 13) and freckled (Group T, n = 16) eggs for 7 consecutive days.ResultsWhen we examined the eggshell quality, we found that the L value was significantly lower (P < 0.05) in the freckled site group of freckled eggs compared to the normal egg group during the detection of blunt pole, equator, and sharp pole of the eggshell color. The a-values of the three positions were significantly higher (P < 0.05) in the freckled site group of freckled eggs, and the a-values of the blunt pole were significantly lower (P < 0.05) in the background site group of freckled eggs, compared to the normal egg group. The b-values were significantly higher (P < 0.05) at three locations in the freckled site group of freckled eggs compared to the normal egg group. During the detection of eggshell thickness, the blunt pole was significantly higher (P < 0.05) in the freckled egg site group of freckled eggs compared to the normal egg group, and there was no significant difference between the other groups (P > 0.05). There was no significant difference (P > 0.05) between the transverse and longitudinal diameters of the eggs in each group.We then performed histopathology and transcriptome analyses on the collected tissue. When compared with group C, uterine junctional epithelial cells in group T showed significant defects and cilia loss, and epithelial tissue was poorly intact. From transcriptomics, genes that met (|log2FC|) ≥ 1 and P < 0.05 criteria were screened as differentially expressed genes (DEGs). We identified a total of 136 DEGs, with 101 up- and 35 down-regulated genes from our RNA-seq data. DEGs identified by enrichment analyses, which were potentially associated with freckled egg production were: IFI6, CCL19, AvBD10, AvBD11, S100A12, POMC, and UCN3. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses showed that pathways were associated with immunoreaction and stress stimulation, e.g., complement activation, interleukin-1 cell reactions, viral responses, cell reactions stimulated by corticotropin releasing hormone, steroid hormone mediated signaling pathways, staphylococcal infections, B cell receptor signaling pathways, and natural killer cell mediated cytotoxicity.ConclusionsFrom these data, freckled areas deepen freckled eggshell color, but background areas are not affected. At the same time,we reasoned that freckle eggs may result from abnormal immune responses and impaired uterine functions induced by stress. Therefore, the uterus of laying hens in a state of stress and abnormal immune function can cause the appearance of freckled eggs.

Adjusting phosphate feeding regimen according to daily rhythm increases eggshell quality via enhancing medullary bone remodeling in laying hens

BackgroundBody phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle. The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms. There is lack of information about the impact of adjusting phosphate feeding regimen according to daily rhythm on the phosphorus homeostasis and bone remodeling of laying hens.Methods and resultsTwo experiments were conducted. In Exp. 1, Hy-Line Brown laying hens (n = 45) were sampled according the oviposition cycle (at 0, 6, 12, and 18 h post-oviposition, and at the next oviposition, respectively; n = 9 at each time point). Diurnal rhythms of body calcium/phosphorus ingestions and excretions, serum calcium/phosphorus levels, oviduct uterus calcium transporter expressions, and medullary bone (MB) remodeling were illustrated. In Exp. 2, two diets with different phosphorus levels (0.32% and 0.14% non-phytate phosphorus (NPP), respectively) were alternately presented to the laying hens. Briefly, four phosphorus feeding regimens in total (each included 6 replicates of 5 hens): (1) fed 0.32% NPP at both 09:00 and 17:00; (2) fed 0.32% NPP at 09:00 and 0.14% NPP at 17:00; (3) fed 0.14% NPP at 09:00 and 0.32% NPP at 17:00; (4) fed 0.14% NPP at both 09:00 and 17:00. As a result, the regimen fed 0.14% NPP at 09:00 and 0.32% NPP at 17:00, which was designed to strengthen intrinsic phosphate circadian rhythms according to the findings in Exp. 1, enhanced (P < 0.05) MB remodeling (indicated by histological images, serum markers and bone mineralization gene expressions), elevated (P < 0.05) oviduct uterus calcium transportation (indicated by transient receptor potential vanilloid 6 protein expression), and subsequently increased (P < 0.05) eggshell thickness, eggshell strength, egg specific gravity and eggshell index in laying hens.ConclusionsThese results underscore the importance of manipulating the sequence of daily phosphorus ingestion, instead of simply controlling dietary phosphate concentrations, in modifying the bone remodeling process. Body phosphorus rhythms will need to be maintained during the daily eggshell calcification cycle.Graphical

Sensory Characteristics, Nutritional Composition, and Quality of Eggs from Different Chickens

The present study evaluated the sensory, composition, and quality of eggs from Cosmopolitan (C), Improved Horro (H), ♂ Improved Horro * Cosmopolitan ♀ (HC), ♂ Cosmopolitan * Improved Horro ♀ (CH), Indigenous(L), and Koekoek (KK) genotypes. A completely randomized design was used in the study. A total of 108 (18/genotype), 180 (30/genotype), and 90 (15/genotype) eggs were used for the sensory, composition, and egg quality tests, respectively. All data were analyzed following the GLM model using SAS software. The boiled and scrambled eggs from L, H, and C were (P ≤ 0.001) preferred followed by CH, HC, and KK. Results showed that KK, HC, CH, and C eggs were higher in moisture, crude fat, crude ash, and crude fiber, but these traits were found lower in H and L genotypes. A significantly highest crude protein was observed in L (21.19 ± 0.19) genotype, with higher in H (20.62 ± 0.26), intermediate in HC (19.96 ± 0.29), C (19.85 ± 0.10), and CH (19.40 ± 0.37), whereas the eggs from KK genotype had the lowest crude protein content (18.69 ± 0.20). The egg quality was (P = 0.001 - 0.01) affected across traits except for eggshell indices (P > 0.05). The genotypes with a negative significant correlation with crude protein had a positive significant correlation with almost all composition and egg external quality traits. The genotypes with positive significant correlations of egg weight had positive significant correlations with most internal egg quality traits except that of yolk weight ratio, yolk albumen ratio, and yolk color. Conclusively: the eggs of L, H, and C genotypes were best favored followed by CH and C, but the KK genotype was the least favored, and these differences were deemed due to genetic variations, and interventions. Furthermore, the eggs laid from genotypes with deep yellow yolk color might be the most nutritious. It could also necessitate future breeding and dietary studies.

Response of Japanese Breeder Quails to Varying Dietary Protein Levels in the Tropics

A three months feeding trial was conducted to assess the effects of feeding varying levels of dietary protein on productive performance, egg quality characteristics and hatchability using 930 six weeks breeders quails. The birds were randomly divided into five dietary treatment groups of 186 birds, and were further replicated three times with 62 birds (50 females, 12 males) per replicate. They were fed five experimental diets containing either 18, 20, 22, 24 or 26% CP. Feed and water were provided ad libitum throughout the experimental period. The results obtained did not show significant effect (P&gt;0.05) on final live weight, % change in body weight, feed conversion ratio, cost per dozen or crate of egg produced, hen-day-production, hen-housed production and peak egg production across the dietary treatments. However, significant differences (P&lt;0.05) were observed for feed intake, age at peak production, egg weight and percent mortality across the dietary treatments. Dietary protein levels had no significant (P&gt;0.05) effects on Haugh unit, egg shape index, percent egg shell, egg shell index, egg specific gravity and egg shell thickness. Significant differences (P&lt;0.05) were observed across dietary treatments for % hatchability, fertility and chick weight at hatch. Chick weight at day-old increased with increase in the level of dietary protein. It was concluded that dietary protein level of 22%CP is required for optimum production, egg quality characteristics and reproductive performance of breeder quails in the tropics

Palygorskite combined probiotics improve the laying performance, hatching performance, egg quality, plasma antioxidative status, and immune response of broiler breeders

This experiment was conducted to investigate the effects of different supplementation levels of palygorskite and probiotics complex (Pal-Pro) on laying performance, hatching performance, egg quality, plasma antioxidative status, and immune response of broiler breeders. A total of 432 Xuefeng black-bone chickens (42-week-old) were randomly assigned into four treatments with six replicates of 18 hens. The broiler breeders were fed the basal diet supplemented with 0, 250, 500, and 750 mg/kg Pal-Pro for 8 weeks. The Pal-Pro supplementation linearly or quadratically increased (p < .05) laying rate, fertilisation rate, hatchability of fertile eggs, heath hatched chicks rate, eggshell thickness, yolk index, total antioxidant capacity, activities of total superoxide dismutase, catalase, glutathione peroxidase, and contents of immunoglobulins, interleukin-2, and tumour necrosis factor-α in plasma. With Pal-Pro supplementation increased, feed convention ratio during 5–8 and 1–8 week, embryo mortality, malondialdehyde linearly decreased (p < .05). This finding suggested that dietary supplementation with 750 mg/kg Pal-Pro administration could improve the antioxidative status and immunoglobulins contents in plasma of broiler breeders, which may contribute to an increase in broiler’s laying rate, hatching performance, egg quality, such as eggshell thickness and yolk index. HIGHLIGHTS Dietary supplementation of Pal-Pro decreased the feed conversion ratio and embryo mortality of broiler breeders. Dietary supplementation of Pal-Pro improved the laying rate, fertility, hatchability of fertile eggs, and yolk index of broiler breeders. Dietary supplementation of Pal-Pro enhanced the antioxidant capacity and the level of immunoglobulins in the plasma.

The performance and egg quality characteristics of layers fed diets containing graded levels of Garcinia kola seed meal

Effects of dietary Garcinia kola meal (bitter kola) on the performance and egg quality characteristics of laying hens were investigated. Four layers diets were made such that diet T0 (control) contained no Garcinia kola meal while diets T2.5, T5.0 and T7.5 contained 2.5%, 5.0% and 7.5% Garcinia kola meal, respectively. Each diet was fed to a group of 30 laying hens at 30 weeks of laying life for 84 days, using completely randomized design (CRD). Each group was further sub-divided into three replicates of 10 hens each. The layers on T2.5 and T5.0 diets added significantly (P &lt; 0.05) less body weight than those on T0 and T7.5 diets. There were no significant differences in their feed intake (P &gt; 0.05). T2.5 significantly (P &lt; 0.05) depressed hen-day egg production but enhanced egg weight. Feed conversion ratio (g feed/ g egg) was not affected by the treatments (P &gt; 0.05). Egg quality indices (egg shape index, egg specific gravity, Haugh unit, egg shell thickness, albumen index and yolk index) were not affected by the treatments (P &gt; 0.05). Egg shell index was significantly (P&lt;0.05) enhanced by Garcinia kola meal. At 2.5% level, it significantly enhanced percent albumin and reduced percent yolk (P&lt;0.05). Cost of egg production (N/kg eggs) was adversely increased as the level of Garcinia kola meal increased.

An assessment of eggshell pigments as non-invasive biomarkers of organochlorine pollutants in gull-billed tern

Eggshell pigmentation has been assessed as an indicator of exposure to environmental pollutants in birds, but these studies have only used reflectance spectrophotometry to measure such pigmentation. The present study is the first one that measures eggshell pigments and pollutants in the same eggs to explore their use as biomarkers in birds. We have studied the concentration of organochlorine pesticides and polychlorinated biphenyls (PCBs) in the content of 97 deserted eggs of gull-billed terns (Gelochelidon nilotica) after the abandonment of the colony in Mesas de Asta (Cádiz, S Spain) in 2012. Eggshell thickness and stage of embryo development were studied together along with the concentrations of protoporphyrin IX and biliverdin in eggshells. p,p′-DDE concentrations were high when compared with other studies done with terns in the Mediterranean basin in the past. p,p′-DDE and PCB levels associated with reduced reproductive success were found in 5.1% and 2.1% of the eggs respectively. Eggshell index was largely affected by the embryo development stage, which highlights the need of knowing this information to avoid potential biases in the interpretation of results. The concentrations of protoporphyrin IX and biliverdin in the eggs of gull-billed terns were negatively associated with DDTs levels, which seems to confirm previous observations with phylogenetically related species.

Response of three laying hen genotypes to two feed calcium levels

The present study aimed to evaluate the effect of two dietary Ca levels (3.00% vs 3.50%) in three hen genotypes (ISA Brown, Bovans Brown and Moravia BSL) on their laying performance and quality of their eggs. In order to evaluate the response to dietary Ca, an experiment was conducted with 300 laying hens. One hundred birds from each genotype were divided into 10 replicates (10 birds/cage/Ca level). To reveal the differences, the following characteristics were measured: hen-day egg production percentage, daily feed intake, egg weight, albumen and yolk weights, Haugh unit, eggshell colour, eggshell weight, eggshell thickness, eggshell strength, egg shape index and eggshell index. A higher Ca level significantly increased the hen-day egg production percentage of Bovans Brown and Moravia BSL, while ISA Brown laying hens had the higher egg production percentage at a lower dietary Ca level (85.97% vs 82.41%). No significant effect of dietary Ca level was observed on any internal egg quality measurements except the Haugh unit. However, the dietary Ca level significantly affected some of external egg quality measurements, namely eggshell colour (P &amp;lt; 0.001), eggshell weight (P = 0.003) and eggshell strength (P = 0.012). The results of the present study show that laying performance and egg quality parameters responded differently according to hen genotype and dietary Ca level. Bovans Brown and Moravia BSL laying hens required higher levels of Ca to keep egg production high, while the eggshell quality measurements were better at the lower dietary Ca level. Thus, it is recommended to adjust the Ca levels in feed to the nutritional requirements of laying hens.

Is the Eggshell Quality Influenced by the Egg Weight or the Breeder Age?

For a long time, it has been said that eggshell quality decreases as eggs increase in size, but this increase is seen as the breeder age advances. Therefore, the present study aimed to evaluate the age and egg weight effect on Cobb 500 broiler breeders on eggshell quality. The quality measures tested were eggshell and mineral matter percentage, eggshell surface, shape and eggshell index, eggshell and membrane thickness and specific gravity. Eggs from 27, 31, 36, 40, 46, 48, 53, 58 and 63 week-old breeders were classified as eggs with a constant weight ranging from 63.8 ± 0.2; and eggs with increasing weight, according to age, being: 55.8g; 60g; 62.2g; 64.2g; 65.2g, 66.6g, 68.1g, 69.9g and 72.5g, respectively. The eggs weight did not influence the eggshell percentage and the specific gravity in seven of the nine tested ages, while for mineral matter in six of the nine studied ages. The shape and shell index, shell and membrane thickness are characteristics independent of egg weight. As the Cobb 500 broiler breeder age advanced, the mineral matter concentration and specific gravity maintained constant, the membrane thickness (R2>70) reduced, and other studied variables were influenced in the same way for both treatments. Thus, the eggshell quality decrease with the advancing age cannot be attributed solely to the increase of egg weight with consequent increase in the eggshell volume and the surface, but there are also age-related factors.

Annual Variability and the Influence of Embryonic Development On Red-Shouldered Hawk (Buteo lineatus) Eggshell Characteristics

Abstract Red-shouldered Hawk (Buteo lineatus) eggs were examined to determine whether mass, eggshell thickness, and a thickness index corrected for egg shape and blowhole size changed as embryos developed. Four different stages of embryonic development (fresh, slight, large, and advanced) were described by the collector (C.F. Stone), or inferred from blowhole diameter measurements, for 286 Red-shouldered Hawk eggs collected in the late 1800s and early 1900s in central New York State. We examined changes in eggshell mass, thickness, and thickness index with linear mixed models with year of collection and clutch size specified as random variables. We also evaluated annual differences in eggshell characteristics with linear mixed models. There was an 8.8% decrease in eggshell mass between eggs with fresh and advanced embryos at the time of collection (F3,242 = 3.4, P = 0.02). Eggshell thickness tended to decrease by 7.5% between eggs with fresh and advanced embryos, but the difference was not significant (F3...

SKELETAL EMBRYONIC DEVELOPMENT AND HATCHING TRAITS AS AFFECTED BY EGGSHELL OSTEOPONTIN PROTEIN DURING TWO STAGES OF EGG LAYING CYCLE

The present experiment was carried out for determining the role of osteopontin protein (OPN) in eggshell on shell quality and consequent effect on skeletal embryos, hatching traits and some physiological parameters besides its relation with two stages of laying cycle of Mandarah chickens (32 to42 vs 52 to 62 wks. of age). The obtained results are summarized as follows:- Osteopontin concentrations (ng/µL) were decreased (P≤0.05) for eggshell of fresh eggs and hatched chicks for eggs produced from elder chickens compared with those from younger ones. The same trend of significant decrease of OPN was observed for tibia of hatched chicks and for chick's blood. Osteopontin concentration decreased (P≤0.05) with the increase of embryonic age with respect to eggshell whereas, it increased for tibia. Younger chickens represented significant increase of eggshell strength, eggshell index, eggshell and eggshell membranes thickness compared to those for elder ones. Embryonic mortality %, hatch time (hr) and chick body weight at pull out (g) were significantly increased for eggs produced from elder chickens compared to those for younger ones while, hatchability of fertile eggs % was significantly decreased. Calcium and phosphorus values were significantly decreased with the increase of flock age for eggshell of fresh eggs and eggshell through different times of incubation besides tibia of embryos at 15th day and for chicks at hatch. Blood constituents of hatched chicks as calcium, phosphorus, and parathyroid hormone were significantly decreased with the increase of chicken age. Relative asymmetry is higher (P≤0.05) for wing, tibia, tarsus and femur lengths of embryos and baby chicks for younger flock compared to elder one except that for tarsus of baby chicks. The contributions of OPN as a major protein in shell structure and subsequent effects on hatching process are proven and this conclusion could set up alternative tool for eggshell quality evaluation and breeding selection programs.

Effect of Turmeric Powder Supplementation to The Age of Sexual Maturity, Physical, and Chemical Quality of The First Japanese Quail’s (Coturnix japonica) Egg

&lt;p&gt;The experiment was conducted to determine the effect of turmeric powder supplementation to the age of sexual maturity, physical, and chemical quality of the first Japanese quail’s (Coturnix japonica) egg. Forty five quails were assigned into a completely randomized design with three treatments (levels of turmeric powder, i.e., 0; 54; and 108 mg/quail/day) and each treatment used 15 quails. Turmeric powder supplementation was conducted before sexual maturity. Feed and drinking water provided ad libitum. Observed egg is an egg that was first produced. Parameters measured were the age of sexual maturity, feed intake, body weight, physical qualities which include: weight of egg, long axis, short axis, weight and thickness of shell, yolk index, Haugh unit, egg shell index. Whereas the observed chemical quality were cholesterol, HDL, LDL, protein, vitamin B12, vitamin A in eggs and egg shell calcium levels. The results showed that administration of turmeric powder can accelerate the age of maturity, increasing the levels of protein, HDL, vitamin A and B12 in eggs, decreasing the cholesterol and LDL content in eggs, but did not affect feed intake, physical quality of eggs and egg shell calcium levels. Based on the results of this study, it can be concluded that supplementation of turmeric powder improve the chemical quality of Japanese quail eggs (Coturnix japonica), so it is good for the development of quail embryos as well as for consumption.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;How to Cite&lt;/strong&gt;&lt;/p&gt;&lt;p&gt;Saraswati, T. R., &amp;amp; Tana, S. (2016). Effect of Turmeric Powder Supplementation To The Age of Sexual Maturity, Physical, and Chemical Quality of The First Japanese Quail’s (Coturnix japonica) Egg. &lt;em&gt;Biosaintifika: Journal of Biology &amp;amp; Biology Education&lt;/em&gt;, 8(1), 18-24.&lt;/p&gt;

THE ROLE OF TURMERIC POWDER IN LIPID METABOLISM AND ITS EFFECT ON QUALITY OF THE FIRST QUAIL’S EGG

This experiment was conducted to determine the role of turmeric powder in lipid metabolism andits influence on the quality of the first quail’s egg. Sixty female quails were assigned into a completelyrandomized design with four treatments (levels of turmeric powder i.e., 0; 13.5; 27; and 54mg/quail/day) and each treatment used 15 quails. The treatment was conducted for 60 days. Parametersmeasured were proximate analysis and the quality of the first layed eggs. At the end of the experiment,serum cholesterol and triglyceride concentrations, abdominal and pectoral fat weights, and feedconsumption were measured. Chemical analysis showed that turmeric powder contained 7.97%curcumin. Supplementation of turmeric powder lowered serum cholesterol and triglycerideconcentrations, egg fat and protein contents, haugh unit and yolk index, but did not affect feed intake,abdominal and pectoral fat weights, egg weight, eggshell weight, eggshell thickness, and egg shellindex. However, quails supplemented with turmeric powder showed a variation in egg laying delayranging from 1 to 16 days. Quails supplemented with 54 mg/d turmeric powder had the highest follicleshierarchy. It was concluded that supplementation of turmeric powder with the level of 54 mg/quail/daydecreased lipid content of the egg and improved the other egg quality parameters.

Long term trends in PBDE concentrations in gannet ( Morus bassanus) eggs from two UK colonies

We used the eggs of an avian sentinel, the Northern gannet ( Morus bassanus), to determine long-term (1977–2007) trends in PBDE contamination in Western Atlantic (Ailsa Craig colony) and North Sea (Bass Rock colony) waters around the UK. BDEs 47, 49, 99, 100, 153, 154 were the most abundant and were found in all eggs. Individual congener and ΣPBDE concentrations in eggs from both colonies increased mainly from the late 1980s, peaked in 1994, and then rapidly declined so that concentrations in 2002 were similar to or lower than those in the 1970s and 1980s. The PBDE congener profile and temporal variation in PBDE concentrations suggests that the Penta-BDE technical formula was the main source of PBDE contamination. However, contributions of heavier BDE congeners to ΣPBDE concentrations have increased over time, suggesting other sources are becoming more important. PBDEs had no measurable effect on egg volume or eggshell index.

The effects of dietary garlic powder on performance, egg yolk and serum cholesterol concentrations in laying quails

This study was conducted to investigate the effects of garlic powder on the performance, egg traits, egg cholesterol and serum parameters of laying Japanese quails. One hundred and twenty 10-weeks-old quails were allocated to four dietary treatments. Quails were caged individually and fed diets supplemented with 0 (control), 1, 2, 4% garlic powder for 12 weeks. There were significant (P &amp;lt; 0.05) differences among the diets in feed consumption, feed efficiency and egg production as averaged over 12 weeks. The better values for these parameters were obtained from the 1% garlic powder supplemented group. Garlic powder addition did not significantly affect egg yolk index, egg shell weight and egg shell thickness. However, there were significant differences (P &amp;lt; 0.05) in egg albumen index, egg shell index and Haugh unit. There was a significant (P &amp;lt; 0.05) reduction in the egg yolk cholesterol concentration when the dietary level of garlic powder was increased from 0 to 4 g/kg. Plasma high density lipoprotein (HDL) cholesterol concentrations increased (P &amp;lt; 0.05) with increasing levels of dietary garlic powder. Plasma cholesterol (P &amp;lt; 0.05) and tri-glyceride (P &amp;lt; 0.05) concentration decreased with garlic powder supplementation. It was concluded that garlic powder in the diet of laying quails reduced the plasma and egg yolk cholesterol concentration.

Effect of different levels of dried citrus pulp on performance, egg quality, and blood parameters of laying hens in early phase of production

Utilization of agricultural wastes in animal nutrition is a matter of great concern. Dried citrus pulp (DCP) is a potential source of some valuable nutrients for animal and poultry. In an experiment with completely randomized design, the effect of different levels (0%, 4%, 8%, 12%, and 16%) of DCP was evaluated on performance, egg quality, and blood parameters of laying hens from 25 to 37 weeks of age. The birds were randomly allocated to five groups with six replicates and three birds in each replicate. The results showed that with increasing the level of DCP up to 12%, there were no significant differences among treatments for feed intake, egg production, egg mass, feed conversion ratio, final body weight, yolk index, and yolk color. There were no significant differences between treatments in shell thickness, eggshell index, egg score, and Haugh unit. Utilization of DCP up to 16% significantly increased serum glucose and high-density lipoprotein and reduced cholesterol, low-density lipoprotein, and triglycerides (P < 0.05). Results of the present study indicated that use of 12% DCP in laying hen diets had no adverse effect on performance and egg quality of laying hens in early phase of production.

Effect of garlic powder on the performance, egg traits and blood parameters of laying hens

AbstractThis study was conducted to investigate the effects of garlic powder on the performance, egg traits and blood parameters of laying hens. One hundred and sixty‐two SHSY‐type brown layers aged 21 weeks were chosen at random from a large flock. They were allocated to three dietary treatments. Each treatment comprised six replicates of nine layers in groups of three. The diets were supplemented with 0, 5 and 10 g kg−1 garlic powder. The experimental period lasted 22 weeks. Garlic powder addition did not significantly affect body weight, egg production, feed consumption, feed efficiency, egg shell index, egg breaking strength, egg shell thickness, egg albumen index, egg yolk index, egg Haugh unit, egg yolk weight and serum protein concentration. Egg weight increased (P &lt; 0.01) with garlic powder supplementation. There was a significant (P &lt; 0.01) reduction in egg cholesterol concentration as mg g−1 yolk when the dietary level of garlic powder was increased from 0 to 10 g kg−1. Hen serum triglyceride (P &lt; 0.05) and total cholesterol (P &lt; 0.01) concentrations decreased with garlic powder supplementation. This study demonstrated that garlic powder addition increased egg weight and decreased egg yolk cholesterol concentration (mg g−1 yolk) and serum triglyceride and cholesterol concentrations without adverse effects on performance and egg traits. Copyright © 2006 Society of Chemical Industry

Heritabilities and genetic and phenotypic correlations of egg quality traits in brown-egg dwarf layers

Albumen height, albumen weight (AW), eggshell color (ESC), eggshell index, eggshell strength, eggshell thickness, eggshell weight (ESW), egg weight (EW), Haugh units, and yolk weight (YW) were measured in 2,272 eggs collected 3 d sequentially from 920 brown-egg dwarf layers caged individually. The restricted maximum likelihood procedure was applied to estimate heritabilities and genotypic and phenotypic correlations for these egg quality traits. Heritabilities of albumen height, AW, ESC, eggshell index, eggshell strength, eggshell thickness, ESW, EW, Haugh units, and YW were 0.51, 0.59, 0.46, 0.40, 0.24, 0.34, 0.64, 0.63, 0.41, and 0.45, respectively. The genetic correlations between EW and AW, YW, and ESW were high ranging from 0.67 to 0.97, whereas those for ESC with external and internal egg quality traits were low ranging from −0.23 to 0.13. Thus although heritabilities for these traits were moderate to high, genetic correlations with ESC were low, suggesting a minor relationship between shell color and physical attributes of the shell as well as internal egg quality in brown-egg dwarf layers.

Reduction of Organochlorine Residues in Goshawk Eggs (Accipiter gentilis) from Northern Germany (1971–2002) and Increasing Eggshell Index

We investigated unhatched eggs (n = 57) of Goshawks (Accipiter gentilis) from the period 1988--2002 and compared them with eggs (n = 134) from 1971--1978. Mean concentrations of PCBs, sigmaDDT and HCB in the earlier period were (mg kg(-1) lipid weight) 50.1, 126.6, and 117.7, while the values from the later period were statistically significantly lower: 27.7, 4.1, 0.1, respectively. Nevertheless, the concentration of PCB is relatively constant during the last 8-10 years. The variability of residues was lower within clutches than among clutches. No age-dependent accumulation in eggs could be demonstrated. A statistically significant lower shell index was measurable for the period 1971--1978, while this index during 2001--2002 was relatively high as it was during the late 18th century. We are suggesting a threshold value for effect concentrations on shell index. Residues of the DDT-group had an influence on the number of fledged young per nest site.