• Asian-Australasian Journal of Animal Sciences
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• v.2 no.2
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• pp.103-114
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• 1989

Reciprocal crosses were conducted between three strains of Taiwan Country chickens, developed in the National Chung-Hsing University, and two strains of Single Comb White Leghorns, developed in the Taiwan Livestock Research Institute. Traits studied were growing performances, laying performances, egg quality traits and traits concerning disease resistance, including resistance to Marek's disease virus and immune responses to Newcastle disease virus vaccine and to sheep red blood cell. Results indicated that laying performances of Taiwan country chickens were much inferior to White Leghorns, but they matured earlier, their eggs had better shell strength and larger proportion of yolk, and their general disease resistance was much better than White Leghorns. Heterosis were found in laying performances and egg quality traits. The heterosis in laying traits was so large that the hybrid laid as many eggs and as large eggs as did pure strains of White Leghorns. Strategies on the improvement of native chickens and the utilization of genetic merits of native chickens were also discussed.

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.2
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• pp.269-272
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• 2004

Different methods of cold storing of bivoltine eggs are in practice to postpone hatching. Bivoltine eggs undergo hibernation if they are not acid treated within 20 - 24 hrs of oviposition, which depends on race, ambient temperature and humidity. The schedules adopted for cold storing include hibernation schedule (Hib), ordinary chilling (OC), short term chilling (STC) and acid treated layings (AT). Peanut cocooning race ${NB_4}{D_2}$ has been subjected for the present assessment. Cocoons harvested from the crop pertaining to all the four methods of cold storing have been used for producing different combinations and acid treated followed by rearing. The performance in respect of chawki loss, maximum larval weight 4({5^th} age)$, yield/ 10,000 larvae (no), cocoon and shell weight showed maximum values for hibernation ${\times}$ hibernation combination followed hibernation with OC and hibernation with AT. Lowest performance was recorded when STC batch source females were used.

• Animal cells and systems
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• v.3 no.4
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• pp.375-383
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• 1999

Gonadal development, gametogenesis, reproductive cycle, and first sexual maturity of Reishia clavigera were investigated monthly from July 1998 to June 1999 through cytological and histological observations. R. clavigera had separate sexes, and was an internal fertilizer. The ma1e penis was located near the two tentacles. The ovary and testis were composed of a great number of oogenic lobules and spermatogenic tubules, respectively. The size of ripe oocyte ranged from 130 to 140 ${\mu}$m in diameter. The peripheral cytoplasm of the germinal vesicle of the ripe oocyte in many cases were surrounded by smaller yolk granules, while the eccentric cytoplasm was occupied with larger ones. The reproductive cycle of R. clavigera could be classified into five successive stages: early active, late active, ripe, spawning, and recovery. Spawning of females occurred from early July to August when the seawater reached above 24.8$^{\circ}C$. Spawning of males occurred from early June to August in the water above 22.8$^{\circ}C$. Minimum size for sexual maturity of both sexes was above 10.0 mm in shell height. Each egg capsule was a cylinder or spindle in shape, 4-6 mm in length and 1-2 mm in width. Colors of newly spawned egg capsules showed yellowish white or pale yellow, while those with veliger larvae showed pale black, and released larvae or dead egg capsules showed black violet. The fecundity in an egg capsule ranged from 70 to 91 eggs (mean＝80.28 eggs).

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.2
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• pp.117-125
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• 2003

To know the impact of female pupal weight corresponding to the male cocoon shell weight upon fecundity, hatchability and percentage of non-viable eggs, the experimental multivoltine breeds namely BL67 and 96A were categorised into low, medium and high batches according to the weight of female pupae and male cocoon shells and moths emerged from low, medium and high female pupae were allowed to mate withmoths emerged from low, medium and high male cocoon shells. Both the experimental breeds of BL67 and 96A revealed a fairl trend in fecundity for high batch ＞ medium batch ＞ low batch. When data were statistically analysed, a significant (p ＜ 0.05) and a highly significant (p ＜ 0.01) increase in fecundity was observed in the medium and high batches of BL67 during November - December, 2002 whereas highly significant (p ＜ 0.01) increase was observed in the high batches of 96A during November - December, 2002. Data revealed a highly significant (p ＜ 0.01) increase in fecundity in medium and high batches of both the breeds during January - February, 2003. More interestingly, a significant (p ＜ 0.05) reduction was noted in percentage of non-viable eggs in high batches of 96A during January - February, 2003. But no significant variation in hatchability was noticed due to the effect of differential female pupal weight and male cocoon shell weight.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.49-55
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• 2013

The objective of this study was to compare the principle components and internal quality of eggs by age of laying hens and weight standard. The eggs (2,140 in total) used were from Hy-Line Brown reared from 18 to 63 weeks of ages and all were higher than appearance grade B by animal grading standard of Korea. Eggs were investigated their principle components, internal quality index, and their relationship. The weights of whole egg, shell, yolk, and albumen were increased while albumen height and Haugh unit were decreased by age of laying hens. When the composition of egg was investigated after sorting by ages, the ratio of egg yolk increased while that of albumen decreased. Egg shell composition was not shown significant difference by age. Age of laying hens had positive correlation with the weights of whole egg, shell, yolk, and albumen while albumen height and Haugh unit showed negative correlation. Also, the albumen height and Haugh unit were decreased by increase of weight of whole egg or principle components of egg.

• Korean Journal of Poultry Science
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• v.25 no.3
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• pp.103-111
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• 1998

This study was carried out to estirnate the heritabilities and genetic correlations on egg shape index and internal egg qualities ; shell thickness, alburnin heights and Haugh units for breeding plan and selection in Korean native chicken. Data analyzed were the records of 46,908 eggs from 43() layers from April, 1994 to September, 1995. The egg shape index at the first egg, 300 days and 500 days of ages were 74.771, 74.468 and 73.702; the shell thickness were 0.345, 0.344 and 0. 334mm; the alburnen heights were 6.579, 6.130 and 5.318mm; the Haugh units were 86.859, 81.014 and 73.565 respectively. The heritability estimates of egg shape index and internal egg qualities based on the variance of sire, dam and combined components at 300 days of age were 0.136, 0.954 and 0.545 for egg shape index; 0.201, 0.622 and 0.421 for shell thickness; 0.410, 0.961 and 0.633 for albumen height ; 0.353, 0.962 and': 0.608 for Haugh units. The genetic correlation coefficient between shell thickness and albumen height was -0.044~0.824; 0.016~0.949 between Haugh units and shell thickness 0.313~0.941 between albumen height and Haugh units, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.6 no.1
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• pp.1-4
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• 1993

Least square means for egg weight (EW), average shell thickness (ST), shape index (SI), shell surface area (SA) and shell breaking strength (BS) were determined in the Philippine native (PN) and F2 upgrades with New Hampshire (NH-N) and White Leghorn (WL-N) blood, respectively. Eggs of PN were smaller in size but had higher SI while their egg shells were thinner and weaker than those of the two upgrades. Highest EW, SA and BS means were observed in WL-N. Significant (p<0.01) positive correlations of EW and SI with SA and BS were noted.

• Korean Journal of Poultry Science
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• v.32 no.3
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• pp.219-224
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• 2005

This study was carried out to investigate the effect of feldspar on laying Performance and e99 qualify in hens. A total of 96 'Tetra Brown' layers were assigned to 4 treatments in a completely randomized design. Each treatment consisted 4 replicates accommodating 6 layers per replication. Experiment diets were a control diet without feldspar and supplemented 0.5, 1.0 and $1.5\%$ feldspar. The egg Production rate was significantly increased in layers 134 diets supplemented 0.5 and $1.0\%$ feldspar compared to that of control (P<0.05). Egg weight, egg mass, feed intake, feed conversion ratio, egg shell strength and egg yolk color were not significantly different among the treatments (P>0.05). The haugh unit and blood spot of the eggs were significantly increased in $1.5\%$ feldspa. diets compared to that of control (p<0.05). However, the albumen index and meat spot in the eggs were not statistically different among treatments (P>0.05). Sensory evaluation traits were not significantly differed in terms of appearance, color, texture flavor and overall acceptability of eggs (P>0.05). The juiciness of boiled eggs was significantly increased in eggs of birds fed $1.0\%$ feldspar diets(P>0.05).

• Korean Journal of Poultry Science
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• v.7 no.1
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• pp.1-11
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• 1980

About 6 to 8% of the eggs annually produced are broken or cracked between the hen and the consumer's carton. The majority of this breakage is due to interrelationships between egg shell quality and the many biological, environmental and managerial factors which have been individually identified as affecting breakage. Some of the factors associated with shell damage discussed in this review include age of hens, temperature ana humidity of the laying house, design of the cage systems and of the cage floors, type of material used to manufacture the cages frequency of daily egg collection in the laying house and, Probably most important, the frequency and quality of handling equipment maintenance. Age and genetic constitution of the hens, environmental temperature, and design and quality of equipment maintenance are the major factors that influence shell breakage. There is a curvilinear relationship between shell quality and shell breakage which explains why small changes in shell quality may be associated with large changes in the incidence of breakage. Published data indicate the incidence of breakage may range from as low as 1 to 2% to 35% or more for other egg producers.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.986-990
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• 2000

The quality characteristics and proximate composition of the eggs of pheasant, chukar, quail, and guinea fowl were compared. Eggs of the 4 species had a similar ovalish conical shape with blunt and pointed ends, showing the shape indices of 77.30-79.63 with no statistical difference. Egg weight was heaviest in guinea fowl (46.65 g), followed by pheasant (25.79 g), chukar (19.16 g) and quail (10.34 g). Proportion of yolk to the total egg weight was highest in pheasant (35.7%), followed by chukar (33.9%), quail (31.4%) and guinea fowl (30.6%). Albumen content was highest in quail showing 61.2%, while pheasant, chukar and guinea fowl were in the range of 55.6~57.4%. The ratio of yolk to albumen (Y/A) was highest in pheasant (0.65), followed by chukar (0.60), guinea fowl (0.55) and quail (0.52). The portion of shell to the total egg weight was highest in guinea fowl (13.5%) and lowest in quail (7.3%). The shell thickness of the eggs was thickest in guinea fowl ($462.8{{\mu}m}$), followed by pheasant ($241.5{{\mu}m}$), chukar ($231.8{{\mu}m}$) and quail ($174.8{{\mu}m}$). The contents of moisture, crude protein, crude fat and crude ash of whole egg were in the ranges of 74.26-74.50%, 11.98-12.77%, 10.83-11.91% and 1.02-1.10%, respectively, with no statistical difference (p>0.05) among the species. Albumen was high in moisture (87.46-87.99%) and very low in crude fat (0.09-0.13%), which was quite different from yolk. Yolk showed relatively low level of moisture (49.71-50.42%) and high levels of fat (31.48-32.32%), crude protein (15.12-15.99%) and crude ash (1.53-1.86%). No species difference in the proximate compositions of albumen and yolk was found except in crude ash content of albumen.