• International Journal of Industrial Entomology and Biomaterials
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• v.16 no.1
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• pp.1-5
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• 2008

The present study was carried out with the aim to evaluate the viability of layings (delivery of fertilized and unfertilized eggs) with egg laying duration of elite bivoltine races. The temporal aspect of mating in terms of egg layings duration may also have impact on the number of eggs laid, pattern of egg laying and their viability. After different interval of egg laying duration, moth of Bombyx mori are removed from oviposition site after they have completed egg laying. Present investigation confirmed that there are no significant difference in relation to the occurrence of viable (fertilized) and non viable (unfertilized) eggs and duration of oviposition. Percentage of unfertilized eggs varied from 2.41 to 3.42% in case of CSR-3, 2.59 to 3.62% in case of CSR-6, 2.82 to 3.66% in case of CSR-16 and 2.58 to 3.40% in case of CSR-17 in different treatments. The occurrence of unfertilized eggs are also not significant in the different treatments specially in those eggs which were laid 24 hours after oviposition and kept for 4 months hibernation schedule.

• Korean Journal of Acupuncture
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• v.20 no.3
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• pp.1-8
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• 2003

Objectives : To investigate the increasing effect of veterinary acupuncture (VA) on the eggs-laying rate, we carried out the experiment in old hens. Methods : Twenty four old hens (ISA Brown; 1,200 - 1,400 g) over 75 weeks old whose eggs-laying rates were under the 50% for recent 15 days were used. In experimental group, VA treatments were performed seven times during 10 days. Unang point at the end of bilateral wing and Migun point at the tail bone were stimulated about 30 seconds by the stainless steel needle (0.3 mm o.d.). In control group, similar manual stress were performed at same frequency. The numbers of laid eggs were observed for 26 days after the beginning of treatment. Bloods were sampled two times from wing veins during and after the treatment period and serum concentrations of luteinizing hormone (LH) and Estradiol were detected. Results : Eggs-laying rates of experimental group $(34.29{\pm}2.79%)$ were significantly increased than that of control group $(27.56{\pm}2.00%,\;p<0.05)$ with the significant increasing of LH serum concentration in experimental group $(from\;0.77{\pm}0.13\;IU/I\;to\; 1.42{\pm}0.22\;IU/I,\;p<0.05)$. Conclusions : Increasing effect of VA treatment on the eggs-laying rate in old hens were proved in this study, and it may be the first prompt on the experimental investigation and development of VA.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.365-368
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• 2004

This study was conducted to investigate change of rate of laying eggs and vitamin according to feeding of far infrared-irradiated rice. The feeding of rice irradiated by far infrared rays did not affect the body weight of laying hens, but the rate of laying eggs were 14% positively increased than normal rice. Especially, the levels of vitamin A(150${\sim}$200%), D(28${\sim}$30%) and E(40${\sim}$67%) were much higher in the group of laying hens fed with rice irradiated by far infrared rays.

• 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.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.341-344
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• 2018

This study was conducted to determine the effects of dietary bentonite supplementation on the fatty acid profiles of eggs in older laying hens. A total of 90 Hy-line Brown layers, 74 weeks of age, were confined in 6 wire cages and then assigned randomly to two groups to receive one of the two diets (3 replicates of 15 older layers each) containing 0 and 0.2% bentonite for 4 weeks. After the 4-week feeding trial, no remarkable differences in individual fatty acid, saturated fatty acid (SFA), unsaturated fatty acid (UFA), and mono unsaturated fatty acid (MUFA) levels were found. However, linoleic acid, docosahexaenoic acid, and poly unsaturated fatty acid (PUFA) and UFA/SFA ratio were influenced by 0.2% bentonite. In conclusion, supplementation with 0.2% bentonite improved the profiles of PUFA more than those of SFA, UFA, and MUFA inthe eggs of the older laying hens.

• Korean Journal of Poultry Science
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• v.47 no.4
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• pp.237-245
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• 2020

This study investigated the effects of breed, laying age, and egg storage period on hatching performance. Eggs were collected from early laying period (27 to 29 weeks old) and late laying period (50 to 52 weeks old) in Hwanggalsaek Jaeraejong, Korean Rhode Island Red, and Korean White Leghorn chicken breeds. Eggs laid for each period were stored for 3, 7 and 14 days and then hatched. Fertility, hatchability, and embryonic mortality were observed to determine the hatching performance. The results showed that hatching performance was affected by breed, laying age, and egg storage period with independently or interactively. The Korean Rhode Island Red breed had the lowest hatching performance. Hatchability and early embryonic mortality rate increased in early laying period eggs compared to the late laying period, but the late embryonic mortality rate increased in late laying period eggs. Additionally, hatching performance decreased as the egg storage period increased. Using breed-specific hatching management techniques, avoiding late laying period eggs, and shortening the egg storage period to seven days after laying may improve the hatching performance.

• International Journal of Industrial Entomology and Biomaterials
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• v.26 no.1
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• pp.22-30
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• 2013

The reproductive performance of multivoltine breed 'Nistari' and bivoltine breeds as NB18, P5 and a bivoltine hybrid (NB18 ${\times}$ P5) of B. mori were studied in different seasons in terms of total number of eggs laid, unlaid and hatching efficiency of the laid eggs to critically assess the breeds / hybrid potentiality. The bivoltine hybrid showed better performance in all the seasons as compared to the breeds investigated, as expected due to possibility of hybrid vigour. Among the breeds, bivoltine P5 had a better egg laid performance in S1 (February - March), S2 (May - June) and S3 (September - October) seasons but with an increase in the number of unlaid eggs. The hatching percentage, although didn't show any definitive trend, still suggested a marginal better performance in the hybrid. Most importantly, egg laying rhythmicity was studied by mating the female moth at 6.00 a.m. for $3{\frac{1}{2}}$ hours, and subsequently allowing the laying of eggs both under BOD condition ($25{\pm}1^{\circ}C$ and $85{\pm}5%$ RH) and at ambient temperature ($23-28^{\circ}C$ and $74.7{\pm}5%$) separately. Maximum (90%) egg laid occurred from 3.30 to 7.30 pm (i.e. 4 - 6 h after decoupling). Similar laying patterns were observed when females where mated at 12 noon and decoupled at 3.30 pm, revealing that late photoperiod and early scotoperiod were favourable for egg laying in case of multivoltine breed and bivoltine prefers late photoperiod for egg laying.

• Korean Journal of Poultry Science
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• v.19 no.4
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• pp.177-185
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• 1992

This study was carried out to investigate the relationship between frequency of soft and broken eggs and the economic traits for colored laying hens using the data sampled 7 times in Korea from 1985 to 1991. In addition, the correlation coefficients of frequency of soft and broken eggs on the economic traits for colored laying hens in order to decrease the frequency of soft and broken eggs were studied. The results obtained were summarized as follows ： 1. For colored laying hens, mean of the sexual maturity(SM) was 163.6 days, hen-day egg Production(HDEP) was 79.49％, hen-housed egg Production(HHEP) was 272.9 eggs, egg weight (EW) was 62.69g and the frequency of soft and broken eggs was 1.363％ during 18∼72wks. For white laying hens, SM was 157.2 days, HDEP was 77.87％, HHEP was 265.1 eggs, EW was 60. 26g and the frequency of soft and broken eggs (FSBE) was 1.174％ during 18∼72wks. 2. Statistical significances were observed in laying viability, SM, HDEP, FR, BW and FSBE during 18 ∼72wks and 18 ∼78wks by year for colored laying hens. 3. Sexual maturity was shortened from 168.5 days to 155.9 days. FSBE decreased from 1.4∼l.69％ to 0.94∼o.89％ during 18∼72wks, and HDEP was increased from 74.5∼75.1％ to 77.8∼80.6％, HHEP was increased to 302.0∼304.6 eggs and FSBE was increased from 1.54∼2.02％ to 0.98％ during 18∼78wks in colored laying hens. 4. Estimate of correlation coefficients between FSBE and trait of SM, EW, 72 wks BW were 0.3985, 0.1072, 0.4225, and those of HDEP, HHEP, FR were -0.5662, -2896, -0.245 during 18∼72wks In colored laying hens, respectively. 5. Estimate of correlation coefficients between FSBE and traits of SM, EW, 78wks BW were 0.3791, 0.1171, 0.4609, and those of HDEP, HHEP, FR were -0.5041, -0.2372, -0.2421 during 18∼78wks in colored laying hens, respectively.

• Journal of Sericultural and Entomological Science
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• v.13 no.2
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• pp.119-122
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• 1971

The following results were obtained through the experiments and study of fertility for silkworm eggs in vagina, oviduct, and ovarial base. The sample eggs were collected after leaving silkworm moth for one week from the date of treatment was given to oviporm orifice of the silkworm moth by heated needle in order to discontinue laying eggs. Those sample silkworm moths were divided into two groups. The first group was under the condition of immediately after the couplation and the second group was under the condition of after the laying eggs in some extend, and both of them were completed couplation. The sample eggs were screened in order to confirm the degree of color which normally be observed as very characteristic during hibernating. 1. About 5% of silkworm out of the total sample were identified as having 1-2 eggs. (See table 1). But, the charasteristic colour of hibernating egg was not observed. The colour was not much different as that of eggs in ovarian duct. 2. Immediately after the couplation, the eggs were not found in vagina under the condition of immediately after the couplation. 3. About 10% of the sample under the condition of after laying eggs in some extend were found having eggs in vagina or oviduct. 4. About 2% of the sample silkworm moth under the condition of immediately after the couplation were found having I fertilized egg in oviduct. 5. No fertilized egg was found in ovarian tube. It seemed that sperm did not enter ovarian tube. 6. Almost the entire eggs were found in ovarian tube under the condition of immediately after the couplation. But, eggs under the condition of after laying eggs in some extend were found around oviduct and vagina due to the continuous movement of silkworm eggs towards oviporus orifice. 7. Sperm is mainly found around seminal receptacle and vagina, and sperm goes into micropyle together with silkworm eggs which were moving towards oviduct.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.7
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• pp.1048-1052
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• 2008

The objective of this study was to determine the effect of sodium selenite and zinc-L-selenomethionine on performance and egg Se concentration in laying hens. Two hundred and twenty-four CP Browns aged 71 weeks were divided according to a $2{\times}3$ factorial in a completely randomized design. One more group without additional Se supplementation was used as a negative control. Each treatment consisted of four replicates and each replicate contained eight laying hens. The dietary treatments were T1: basal diet; T2, T3 and T4: basal diets plus 0.3, 1.0 and 3.0 mg Se from sodium selenite/kg, respectively; T5, T6 and T7: basal diets plus 0.3, 1.0 and 3.0 mg Se from zinc-L-selenomethionine/kg, respectively. The findings revealed that feed conversion rate/kg eggs, egg production, egg weight, Haugh units and eggshell thickness were not affected by source and level of Se (p>0.05). Increasing level of dietary Se significantly increased (p<0.05 the Se content of eggs. Zinc-L-selenomethionine markedly increased p<0.05 egg Se concentration as compared with sodium selenite. The results indicated that Se source did not influence performance of laying hens. However, zinc-L-selenomethionine increased p<0.05 egg Se concentration more than sodium selenite.