• 한국어류학회지
• /
• 제35권3호
• /
• pp.151-159
• /
• 2023

이 연구는 한강 수계 보통천에 서식하는 좀구굴치의 초기생활사를 규명하고 근연종과 유연관계를 비교하였다. 좀구굴치의 수정란은 타원형으로 평균 난경은 장경 1.23 mm, 단경 0.85 mm 였다. 수온 20.6℃에서 부화 시간은 179시간이 소요되었다. 부화자어의 크기는 전장 3.82~4.08 mm로 입과 항문이 완전히 발달하지 않았다. 후기자어기는 부화 후 18일째 전장 7.97~8.43 mm로 척색말단 끝부분이 45°로 완전히 휘어졌다. 치어기는 부화 후 29일째 전장 9.83~10.8 mm로 지느러미 줄기 수는 정수에 달하였다. 연구 결과 좀구굴치는 난 크기, 부화자어 크기, 유영형태에서 근연종과 차이를 보였다. 후기자어 이행시기와 제1등지느러미 발달 시기는 비교한 근연종 중 가장 느렸고, 크기는 큰 특징을 보여 초기생활사에서 근연종과의 차이점을 확인할 수 있었다.

• Parasites, Hosts and Diseases
• /
• 제47권3호
• /
• pp.315-318
• /
• 2009

Quantitative fecal egg counts represented as the number of eggs per gram of feces (EPG) are generally a reliable parameter to estimate the worm burden of intestinal and hepatic parasitoses. Although Haplorchis taichui (Digenea: Heterophyidae) is one of the most common minute human intestinal flukes, little is known about the relationship between EPG and the actual worm burden in patients or the severity of the disease. In the present study, fecal samples were collected from 25 villagers in northern Thailand before and after praziquantel treatment. The EPG values of each participant were determined by the modified cellophane thick smear method, and adult worms were collected from the whole stool after the treatment. Eggs per day per worm (EPDPW) of H. taichui were estimated 82 from egg counts and expelled worms. The EPG was not well correlated with the worm burden, and a reverse correlation was observed between the EPDPW and the worm burden.

• 대한수의학회지
• /
• 제11권1호
• /
• pp.49-53
• /
• 1971

The anthelmentic effects of Fuadin (sodium antimony-III-bis-pyrocatechin-disulphonate), Bithionol 2-2-thiobis 4,6-dichlorophenol)), hexachlorethane and carbon tetrachloride were studied on Eurytrema pancreaticum infected in sheep and goats. The evaluation on the effects was based upon the egg reduction in the feces of the experimental animals administered the drugs. The number of eggs per 5gm. of the feces was respectively calculated before the treatments, and the follw-up for the egg reductions was carried out over a period of three or four weeks(calculated twice a week). Oral administration of Bithionol (once a day for 2 succeed days, at the rate of 75 mg per kg of bady weight) and of hexachlorethane (once a day, at the rate of 300ml per kg of body weight) did not reveal any egg reduction in sheep host. Intramuscular injection of carbon tetrachloride with olive oil (once a day, at the rate of 0.05ml per kg of body weight) did not show the egg reduction in goats. Intramuscular injections of Fuadin for 5 days (the dosage schedule was 0.5ml at 1st day, 1.0ml at 2nd and 3rd day, 1.5ml at 4th and 5th day, to amount of 5.5ml) were completely devoid the fluke eggs in the feces of goats on 4 weeks after each treatment. Throughout the studies, Fuadin was only proved its anthelmintic effect to the goats infected with E. pancreaticum. On the other hand, Bithional, hexachlorethane and carbon tetrachloride did not reveal any effect as Fuadin showed.

• Asian-Australasian Journal of Animal Sciences
• /
• 제27권8호
• /
• pp.1075-1081
• /
• 2014

CRBP1 (cellular retinol binding protein 1) and CRBP3 (cellular retinol binding protein 3), are important components of the retinoid signaling pathway and take part in vitamin A absorption, transport and metabolism. Based on the role of vitamin A in chicken laying performance, we investigated the polymorphism of CRBP1 and CRBP3 genes in 349 chickens using single strand conformation polymorphism and DNA sequencing methods. Only one polymorphism was identified in the third intron of CRBP1, two polymorphisms were detected in CRBP3; they were located in the second intron and the third intron respectively. The association studies between these three SNPs and laying performance traits were performed in Erlang mountainous chicken. Notably, the SNP g.14604G>T of CRBP1 was shown to be significantly associated with body weight at first egg (BWFE), age at first egg (AFE), weight at first egg (WFE) and total number of eggs with 300 age (EN). The CRBP3 polymorphism g.934C>G was associated with AFE, and the g.1324A>G was associated with AFE and BWFE, but none of these polymorphisms were associated with egg quality traits. Haplotype combinations constructed on these two SNPs of CRBP3 gene were associated with BWFE and AFE. In particular, diplotype H2H2 had positive effect on AFE, BWFE, EN, and average egg-laying interval. We herein describe for the first time basic research on the polymorphism of chicken CRBP1 and CRBP3 genes that is predictive of genetic potential for laying performance in chicken.

• Animal cells and systems
• /
• 제3권4호
• /
• pp.375-383
• /
• 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).

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권6호
• /
• pp.772-776
• /
• 2010

This study was conducted to investigate the effect of dietary domestic Skullcap (Scutellaria baicalensis) extracts (SCE) on laying performance and egg quality in laying hens. There were no significant differences in feed intake, egg production, or relative liver and spleen weights. The egg weights in groups fed diets containing SCE were significantly increased as compared with the control. The number of cecal total microbes in the group fed a diet containing 0.5% SCE was significantly reduced as compared with other groups. The malondialdehyde contents in stored eggs were significantly lowered by feeding SCE. The Haugh unit in the groups fed diets containing SCE tended to be increased after 2 weeks storage, but not significantly. This result indicated that dietary domestic SCE may delay lipid oxidation in eggs when added to laying hen diets.

• The Korean Journal of Ecology
• /
• 제25권4호
• /
• pp.241-245
• /
• 2002

During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations in overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggesting the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The averagee number of days of hatching asynchrony was 2.5, raging 0.5~2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

• International Journal of Industrial Entomology and Biomaterials
• /
• 제14권1호
• /
• pp.45-50
• /
• 2007

Ethanol extract of 20 botanicals in 3 concentrations i.e., 2.5%, 5% and 10% were evaluated for their efficacy to improve reproductive performance of mulberry silkworm (Bombyx mod L.) through feeding botanical enriched mulberry leaves during $2^{nd}$ day of $4^{th}$ age as well as $1^{st}$ and $3^{rd}$ day of $5^{th}$ age larvae. The preliminary screening was done by ranking the botanicals based on influence in most important reproductive contributing parameters such as single cocoon weight, effective rate of rearing, pupation rate, fecundity and recovery of eggs/kg cocoon. Five botanicals viz., Asparagus recemosus, Achyranthes aspera, Tribulus terrestris, Withania somnifera, Parthenium histerophorus ranked first were further evaluated at 8% 5% and 3% concentrations to confirm their effectiveness and standardize effective concentration. Among the rearing parameters, mature larval weight, shell ratio and number of cocoons/kg were not significantly influenced by the treatments. However, reproductive parameters such as effective rate of rearing (wt), pupation rate (%), fecundity (No.) and egg recovery (g)/kg cocoon were significantly (P<0.05) influenced by the botanicals. Higher fecundity and egg recovery were obtained on treatment with Withania somnifera irrespective of concentrations. However at 5% concentration, pupation rate, fecundity as well as egg recovery were found significantly higher than that of other concentrations, confirming its effectiveness for improving reproductive efficiency.

• Asian-Australasian Journal of Animal Sciences
• /
• 제12권7호
• /
• pp.1085-1089
• /
• 1999

Energy requirement of Rhode Island Red (RIR) hens was studied by comparative slaughter technique. Seventeen hens above 72 weeks of age were slaughtered in batches. Batch I consisted of 5 hens which were slaughtered initially. Batch II comprised of six hens, which were fed ad libitum broken rice (BR)-based diet for 18 days. Record of feed intake, number of eggs laid and egg weight during the period was kept. These hens were slaughtered and body energy content was determined. Egg energy was consisted as energy deposited. Batch III consisting of six hens which were fed varying quantity of diet for 15 days, were slaughtered similarly as hens of batch II. Regression equation (body weight to body energy) developed on batch I was applied to batch II and developed on batch II was applied to batch III hens, to find out initial body energy content of hens. Egg energy (EE) was calculated according to formula: EE (kcal) = -19.7 + 1.81 egg weight (g). Regressing metabolisable energy (ME) intake on energy balance (body energy change + egg energy), maintenance ME requirement of hens was found to be $119.8kcal/kg\;W^{0.75}/d$. Multiple regression of ME required for production on energy retained as protein and fat (body plus egg energy) indicated that RIR hens synthesize proteins with an efficiency of 85.5 and fat with an efficiency exceeding 100 percent on BR based diet.

• 한국발생생물학회지:발생과생식
• /
• 제17권3호
• /
• pp.247-255
• /
• 2013

The gonadsomatic index (GSI) of mottled skate was the highest in April, GSI and HSI showed a reverse phase for its reproductive cycle. The fish had one pair of egg capsules, having 1 to 7 fertilized eggs, and spawned all the year round. When surveying the reproductive characteristics of females over 63 cm in disc width, we found the spawning peak was between April to June, and the appearance ratio of egg capsules was the highest in May (32.1%). The eggs were hatched at $8^{\circ}C$, $13^{\circ}C$, $18^{\circ}C$, water temperature (12.8 to $24.2^{\circ}C$), and the best hatching temperature was $18^{\circ}C$. The number of fish hatched was 4 to 5 fish/egg capsules, and the hatching rate was 100%. The sex ratios of hatching larvae were 45.5% female and 54.5% male. Therefore this study will provide fundamental data and information for artificial reproduction of the mottled skate.