Comparison of breaking strength and shell thickness as evaluators of white-faced ibis eggshell quality

1990 ◽  
Vol 9 (6) ◽  
pp. 797-805 ◽  
Author(s):  
Charles J. Henny ◽  
Jewel K. Bennett
1988 ◽  
Vol 7 (5) ◽  
pp. 351-357 ◽  
Author(s):  
Jewel K. Bennett ◽  
Robert K. Ringer ◽  
Richard S. Bennett ◽  
Bill A. Williams ◽  
Philip E. Humphrey

2018 ◽  
Vol 18 (1) ◽  
pp. 167-183 ◽  
Author(s):  
Sylwester Świątkiewicz ◽  
Anna Arczewska-Włosek ◽  
Józefa Krawczyk ◽  
Witold Szczurek ◽  
Michał Puchała ◽  
...  

Abstract The aim of the experiment with 240 ISA Brown hens fed the diets with standard or decreased Ca level was to evaluate the effect of selected feed additives on laying performance and eggshell quality. The hens were allocated to 10 treatments, each containing 12 cages (replicates) of 2 birds. A 2 × 5 experimental arrangement was used. From 26 to 70 wks of age, experimental diets containing 3.20 or 3.70% Ca were used. The diets were either not supplemented, or supplemented with sodium butyrate, probiotic bacteria, herb extracts blend or chitosan. The decreased dietary Ca reduced eggshell quality indices in older hens (43-69 wks) (P<0.05) without effect on performance indices. The addition of the probiotic, herb extracts, or chitosan increased the laying rate (P<0.05). In older hens, i.e. at 69 wk, chitosan increased eggshell thickness and breaking strength, while herb extracts increased eggshell thickness (P<0.05). There was no interaction between the experimental factors in performance and eggshell quality. The used feed additives had no influence on fatty acid profile of egg lipids, however diet supplementation with chitosan decreased cholesterol concentration in egg yolk lipids (P<0.05). It can be concluded that such feed additives as probiotic, herb extracts, or chitosan may positively affect performance and eggshell quality, irrespective of Ca dietary level.


2011 ◽  
Vol 56 (No. 9) ◽  
pp. 406-413 ◽  
Author(s):  
K. Żyła ◽  
M. Mika ◽  
S. Świątkiewicz ◽  
J. Koreleski ◽  
J. Piironen

A study was conducted to evaluate the effects of dietary supplementation of phytase B (product of the Aspergillus niger phyB gene expressed in Trichoderma reesei) on feed intake, laying performance, eggshell quality, and on phosphorus and calcium balance in laying hens. Seventy-two, 40 weeks old Hy Line Brown hens were fed for 14 weeks the following four phosphorus-deficient (0.12% nonphytate phosphorus, NPP), maize-soybean meal-based diets: (1) calcium-deficient (2.8% Ca) control diet; (2) diet 1 + phytase B at the activity of 2.5&nbsp;acid phosphatase units (AcPU/kg); (3) control diet (3.8% Ca); (4) diet 3 + phytase B at the activity of 2.5 AcPU/ kg. Each dietary treatment was fed to 18 cages of hens, 1 hen/cage kept in individual cages. Hens fed the NPP- and Ca-deficient diets consumed more feed (P &lt; 0.01) and excreted less calcium (P &lt; 0.01) than those receiving P-deficient diets with the standard calcium level. There were no effects of calcium level on feed utilization, egg mass, egg weight, and eggshell breaking strength. Egg production, although numerically higher in hens fed low Ca diets with no enzyme added, failed to be significantly different due to the low number of hens investigated and therefore the measurement should be considered as preliminary and supplementary. Phytase B increased mean egg weight by about 7% in layers fed the NPP- and Ca-deficient diet (Ca &times; phytase B interaction, P &lt; 0.05), increased shell breaking strength, particularly at the standard calcium level, significantly enhanced amounts of calcium retained by layers and amounts of&nbsp; phosphorus retained by hens fed the Ca-deficient diets. Additionally, phytase B improved Ca retention at both dietary Ca levels and phosphorus retention in hens fed the Ca-deficient diets. Results of the study indicate that the efficacy of phytase B in NPP-deficient diets is strongly influenced by the dietary calcium level and the enzyme may modulate egg weight, eggshell quality, phosphorus and calcium retention in laying hens fed low-NPP, maize-soybean meal-based diets.


2004 ◽  
Vol 20 (3-4) ◽  
pp. 107-111 ◽  
Author(s):  
Dusko Vitorovic ◽  
Zlatica Pavlovski ◽  
Zdenka Skrbic ◽  
Milos Lukic ◽  
Ivana Adamovic

Eggshell quality was studied in two groups of Shaver hens (300 hens per group) 30 weeks of age. All hens received a basic diet of the same composition with pulverized limestone as a source of calcium. The experimental group received 2 g of granular limestone (particle size 1.1-1.4 mm) per hen per day during one week, adding on the concentrate in the afternoon. Significantly lower deformation (19 m), higher breaking force (4,1 kg) and shell thickness (39, 3 x 0.01 mm) were registered for eggs of experimental group of hens than for eggs of control group (24 m; 3.3 kg 36.5 x 0.01 mm, respectively). The results obtained in our investigation showed possibilities of eggshell strength improvement using 2 g of larger particle size of limestone as additional source of calcium.


1979 ◽  
Vol 27 (2) ◽  
pp. 176-183
Author(s):  
A.R. El Boushy

1. For 6 months 432 medium heavy laying hens were given diets which supplied 0.16, 0.20, 0.40, 0.60, 0.80 or 1.00% available phosphorus. Egg production was greatest by hens given 0.20 or 0.40% P and least by those given 0.16%. Feed intake did not differ among groups. Heaviest eggs, 62.2 g, were laid by hens given 1.00% P. Shell quality, determined from shell percentage, shell thickness and shell index, decreased as P in the diet increased. Hatchability, yolk and white indices of eggs and calcium, P and ash in tibiae of chicks one day old did not differ among groups. Ca in blood of hens did not differ among groups but inorganic P in plasma increased with increasing P in the diet. Ash, Ca and P in tibiae and breaking strength of tibiae of hens increased with increasing P in the diet. (Abstract retrieved from CAB Abstracts by CABI’s permission)


2010 ◽  
Vol 55 (No. 2) ◽  
pp. 66-74 ◽  
Author(s):  
H. Arpášová ◽  
M. Halaj ◽  
P. Halaj

Hens of the laying hybrid Shaver Starcross 288 were used in two consequential experiments. The first experiment (for 10 months) was conducted on hens at the age from 18 to 60 weeks (1<sup>st</sup> cycle; <i>n</i> = 50) and moulted hens after 10 months laying from 70 to 110 weeks of age (2<sup>nd</sup> cycle; <i>n</i> = 50). For the second experiment (for 8 months) in the 1<sup>st</sup> cycle 18 weeks old hens were bought (<i>n</i> = 60) and hens from the first experiment after moulting were used in the 2<sup>nd</sup> and 3<sup>rd</sup> cycle (<i>n</i> = 32 and <i>n</i> = 28). During the experiments eggshell qualitative parameters and calcium utilisation (%) were determined. The results indicate that the percentage of eggshell decreased with the increasing number of cycles. The significant correlation of the eggshell proportion and the age of hens was higher in long, advanced cycles (<i>P</i> < 0.05). The shell strength in both experiments decreased slightly in relation to the age of hens and repeated laying cycles. The shell deformation had an opposite trend to the shell strength, i.e. it increased with the increasing laying. The average shell thickness showed a decrease in the repeated laying cycles, more significant in shorter cycles (<i>P</i> < 0.01). The specific shell gravity maintained balanced values both in cycles and by the age of hens. The shell density in all cycles in both experiments showed a decreasing tendency in relation to the age of hens. In dietary calcium utilization for the shell formation a significant decrease was recorded in the second cycles after moulting (<i>P</i> < 0.05).


1970 ◽  
Vol 18 (1) ◽  
pp. 62-71 ◽  
Author(s):  
A.R. El Boushy ◽  
M. Van Albada

For a month 24 pullets 7 months old were kept in 2 rooms at 65 degrees to 70 degrees F and relative humidity 50 to 60% and were given a layer's mash with 2.75% Ca. The temperature of one room was then reduced to 55 degrees . For 6 months that of the other was raised to 85 degrees and the humidity to 75 to 80% for 2 months then reduced to the original conditions for 2.5 months and raised again for the rest of the experimental period. Ascorbic acid was given for the last 2 months. Sp. gr. of eggs and shell deformation, breaking strength and percentage shell, but not thickness, tended to fall throughout the trial. Heat stress significantly reduced all aspects of shell quality. In the cold room ascorbic acid did not significantly affect shell quality. In the hot room it increased sp. gr., weight and percentage shell but not shell thickness, breaking strength or deformation. In the cold room plasma Ca did not change significantly. High temperature and humidity significantly reduced plasma Ca, and ascorbic acid in the hot room raised it.-G. F. H. (Abstract retrieved from CAB Abstracts by CABI’s permission)


Author(s):  
Emine Polat Yurtseven ◽  
Ahmet Şekeroğlu ◽  
Brian Tainika ◽  
Mustafa Duman ◽  
Yunus Emre Şentürk

This study compared egg quality parameters in layers under free-range system with prefabricated pens and backyard while emphasizing hen age. A total of 300 eggs collected from prefabricated pens and backyard farming families in the Çamardı District of Niğde Province were used as study materials. The assessed external and internal egg quality characteristics included egg weight, shape index, shell thickness, shell breaking strength, albumen index, Haugh unit, yolk index, and yolk colour. The effect of production system on albumen index, Haugh unit, and yolk colour score was found statistically significant. There was a significant effect of age on shape index, shell thickness, shell breaking strength, albumen index, Haugh Unit, yolk index, and yolk colour score. The effect of interaction between age and production system was statistically significant for shape index, shell thickness, yolk index, Haugh Unit, and yolk colour score. It was determined that the egg`s meat and blood spots percentages from the free-range and backyard systems were 10.6% and 15.3%, respectively. It was concluded that while eggs produced from free-range system are superior in terms of egg weight, shape index, and Haugh unit those obtained from backyard hens are higher in eggshell thickness, eggshell breaking strength, and egg yolk colour.


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