• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.31-38
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• 2004

Data from five Hanwoo breeding farms were collected to analyze the effects of parity, season, nutrition and reproduction on body conditions of heifers and cows and to analyze the relationships of body conditions with reproductive performances and body growth. Analytic models included farms and parity which were run through SAS to estimate least squares means and correlation coeflicients between traits body condition scores(BCS) of I(very emaciated) through 9(very obese) scale at service and at calving. calving interval, days to rebreeding, gestation length. number of services per conception. Overall averages were 4.55 for BCS at service, 5.42 for BCS at calving. 406.7days of calving interval, 287.7days of gestation length, 66.2days from calving 10 first service and 1.78 times of services per conception. Number of services per conception was 1.50${\sim}$1.74 times for the cows of BCS 5 or under and 2.00${\sim}$3.00 for those of BCS 6 or higher. Body weight of calves from cows observed averaged 23.3kg at birth and 70.7kg at weaning. 57 percent of cows showed BCS 4${\sim}$5 at service while 46 percent of those showed 5${\sim}$6 at calving. Estimated phenotypic correlation coefficients of BCS at service with BCS at calving, calving interval, gestation length, number of services per conception were low but positive: 0.16, 0.26. 0.08 and 0.06. respectively. Phenotypic correlations of BCS at calving with calving interval, gestation length and number of services per conception were estimated to be also low and positive: 0.10, 0.13 and 0.10. respectively. However, phenotypic correlations between calving interval and gestation length, and between gestation length and number of services per conception were negative but low as - 0.11 and- 0.13 each.

• Toxicological Research
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• v.19 no.1
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• pp.21-27
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• 2003

A teratogenic study of dimethyl dimethoxy biphenylate derivative (DDB-S) was carried out on Sprague-Dawley rats. DDB-S dissolved in saline was administered to male and female rats by intravenously injection at daily doses of 50 mg/kg, 75 mg/kg, and 100 mg/kg. A half of dams were sacrificed at 20th day of gestation to scrutinize the pregnant performances and fetal development. And the remaining dams were allowed to deliver. The growth, reflex, behaviour and reproductive function of F1 offsprings were examined. There was no treatment-related difference in body weight, food consumption and necropsy findings of dams. No gross, skeletal and visceral abnormalities was observed in F1 fetuses from dams treated with DDB-S. F1 offsprings did not show any treatment-related difference in growth, reflex, behaviour and reproductive performance. At caesarean section of F1 dams, no growth retardation and gross abnormality was observed in F2 fetuses. In conclusion, DDB-S did not show any potential teratogenic effect in rats.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.477-484
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• 2002

Ninety pre-puberal (6-7 months) female and 15 pre-puberal male Black Bengal goats were collected on the basis of their phenotypic characteristics from different parts of Bangladesh. Goats were reared under semi-intensive management, in permanent house. The animals were vaccinated against Peste Des Petits Ruminants (PPR), drenched with anthelmentics and deeped in 0.5% Melathion solution. They were allowed to graze 6-7 h along with supplemental concentrate and green forages. Concentrates were supplied either 200-300 g/d (low level feeding) or quantity that supply NRC (1981) recommended nutrient (high level of feeding). Different physiological, productive and reproductive characteristics of the breed were recorded. At noon (temperature=$95^{\circ}F$ and light intensity=60480 LUX) rectal temperature and respiration rate of adult male and female increased from 100.8 to $104.8^{\circ}F$ and 35 to 115 breath/min, indicated a heat stress situation. Young female attain puberty at an average age and weight of 7.2$\pm$0.18 months and 8.89$\pm$0.33 kg respectively. Mean age and weight at 1st kidding were 13.5$\pm$0.49 months and 15.3$\pm$0.44 kg respectively. It required 1.24-1.68 services per conception with an average gestation length of 146 days. At low level of feeding the postpartum estrus interval was 37$\pm$2.6 days, which reduced (p<0.05) with high feeding level to 21$\pm$6.9 days. Kidding interval also reduced (p<0.05) from 192 d at low feeding level to 177 d at high feeding level. On an average there were two kiddings/doe/year. Average litter sizes in the 1st, 2nd, 3rd and 4th parity were 1.29, 1.71, 1.87 and 2.17 respectively. Birth weights of male and female kids were 1.24 and 1.20 kg respectively, which increased (p<0.05) with better feeding. Although kid mortality was affected (p<0.05) by dam's weight at kidding, birth weight of kid, milk yield of dam, parity of kidding, season of birth, but pre-netal dam's nutrition found to be the most important factor. Kid mortality reduced from 35% at low level of feeding to 6.5% at high level of feeding of dam during gestation. Apparently, this was due to high (p<0.05) average daily milk yield (334 vs. 556 g/d) and heavier and stronger kid at birth at high feeding level.

• Korean Journal of Animal Reproduction
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• v.15 no.1
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• pp.15-22
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• 1991

To determine the preventive effects of selenium and/or vitamin E on placenta retention in Holstein dairy cows. The cows were divided six groups ; control, Se, vit.E 1x, vit.E 3x, Se + vit./E 1x and Se + vit.E 3x in Cooong Nam province. 50mg of Se as sodium selenite and 700 IU of vit. E as dl-${\alpha}$ tocopherol acetate were injected 21 day perior to expected calving date, and 700 IU vit.E was injected 3 times at 21, 14 and 7 days perior to expected calving date in vit.E 3x groups. The cows which did not expelled their placenta until 12 hours post-parturient were termed as cow of placenta retention. The i.m. injection of a single dose of selenium and vit.E has significantly(P<0.05) affected the incidence of retained placenta by 7.0% versus 25.6% of controls, but a single injection of selenium or vit.E and a combination of selenium 1x and vit.E 3x has not significantly affected. But they affected neiher subsequent reproductive performances nor milk yields.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.25-25
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• 2022

Drought becomes frequent and severe because of continuous global warming, leading to a significant loss of crop yield. In soybean (Glycine max [L.]), most of quantitative trait loci (QTLs) analyses for drought tolerance have conducted by investigating yield changes under water-restricted conditions at the reproductive stages. More recently, the necessity of QTL studies to use physiological indices responding to drought at the early growth stages besides the reproductive ones has arisen due to the unpredictable and prevalent occurrence of drought throughout the soybean growing season. In this study, we thus identified QTLs conferring wilting scores and moisture contents of soybean subjected to drought stress in the early vegetative stage using an recombinant inbred line (RIL) population derived from a cross between Taekwang (drought-sensitive) and SS2-2 (drought-tolerant). For the two traits, the same major QTL was located on chromosome 10, accounting for up to 11.5% of phenotypic variance explained with LOD score of 12.5. This QTL overlaps with a reported QTL for the limited transpiration trait in soybean and harbors an ortholog of the Arabidopsis ABA and drought-induced RING-D UF1117 gene. Meanwhile, one of important features of plant drought tolerance is their ability to limit transpiration rates under high vapor pressure deficiency in response to mitigate water loss. However, monitoring their transpiration rates is time-consuming and laborious. Therefore, only a few population-level studies regarding transpiration rates under the drought condition have been reported so far. Via employing an Arduino-based platform, for the reasons addressed, we are measuring and recording total pot weights of soybean plants every hour from the 1^st day after water restriction to the days when the half of the RILs exhibited permanent tissue damage in at least one trifoliate. Gradual decrease in moisture of soil in pots as time passes refers increase in the severity of drought stress. By tracking changes in the total pot weights of soybean plants, we will infer transpiration rates of the mapping parents and their RILs according to different levels of VPD and drought stress. The profile of transpiration rates from different levels of severity in the stresses facilitates a better understanding of relationship between transpiration-related features, such as limited maximum transpiration rates, to water saving performances, as well as those to other drought-responsive phenotypes. Our findings will provide primary insights on drought tolerance mechanisms in soybean and useful resources for improvement of soybean varieties tolerant to drought stress.

• Journal of Animal Science and Technology
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• v.66 no.1
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• pp.135-144
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• 2024

The objective of this study was to investigate the influence of feeding frequency on a sow's reproductive performance and stress response during gestation. A total of twenty multiparous sows (Yorkshire × Landrace) were used in a completely randomized design based on their parity, body weight (BW), and backfat thickness (BFT), and the sows were allotted to two different feeding systems: 1) once daily feeding (OF) and 2) twice daily feeding (TF) in corn-soybean meal based diets. The gestation diet was formulated to contain 3,265 kcal of metabolizable energy (ME) / kg, 12.90% of crude protein (CP), and 0.75 % of total lysine. The lactation diet was formulated to contain 3,265 kcal of ME / kg, 16.80% of CP, and 1.08% of total lysine and provided ad libitum during lactation. In gestation, sow BFT and BF changes were not affected by feeding frequency, but higher BW and BW gain from day 35 to 90 and day 35 to 110 were observed in OF sow (p < 0.10). In lactation, feeding frequency did not influence on BW, BW gain, BFT, BF changes, average daily feed intake, and wean-to-estrus interval. Also, there were no differences in litter size, litter weight and piglet weight in lactating sows. OF sows had higher (p < 0.05; p < 0.10) protein, solid-not-fat, and total solid concentrations in colostrum compared to TF sows, while OF sows had a lower (p < 0.05) lactose concentration in colostrum compared to TF sows. Sows in OF showed significantly lower average daily water consumption (ADWC) from day 35 to 110 of gestation (p < 0.05). While there were no significant differences in stereotypic behaviors and salivary cortisol levels during gestation between treatments, the OF sows showed less time spending on the activity at day 105 (p < 0.05). In conclusion, reduced feeding frequency increased BW gain during gestation, decreased activation time, and changed the colostrum composition. This information may contribute to the understanding of the physiological and behavioral change of gestating sows by manipulating feeding frequency.

• Korean Journal of Poultry Science
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• v.39 no.1
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• pp.9-15
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• 2012

The aim of this study was to investigate phenotypic characteristics, morphometric measurements, reproduction and production performances of Aseel chicken of Bangladesh. The dominant feather color of neck/hackles was red in both males (56.14%) and females (54.16%) while the sickle feather color was mostly black in both chickens (71.93% vs. 54.17%). The predominant saddle and breast feather colors were red (40.35%) and black (64.91%), respectively, in male whereas most frequent observed color was pale brown in female (58.33 and 50.0%, respectively). The predominant feather color of wing bow and wing bay was found black (68.42 and 80.70%, respectively) in male but only pale brown color was observed in females (62.5 and 54.17%, respectively) for these two characters. Different phenotypic measurements such as the average shank length and circumference were $12.79{\pm}0.13$ and $7.8{\pm}0.08$ cm, respectively, in male and $10.21{\pm}0.25$ and $5.81{\pm}0.21$ cm, respectively, in female. Keel length was $14.39{\pm}0.19$ cm in male and $10.79{\pm}0.23$ cm in female. The average adult live weight in male was measured $3749.12{\pm}83.44$ g while in female it was $2062.50{\pm}105.26$ g. The age of 1st lay was found to be 28.86 weeks. Total number of eggs laid per year ranged between 24~48, number of clutch/hen/year varied from 2 to 4 and number of eggs/clutch/hen was found to be 10~12. The average live weight of Aseel chicken at 1, 2, 3, 4, 6, 8, 10, 12, 16 and 17 weeks of age were recorded as $31.14{\pm}0.55$, $48.63{\pm}3.99$, $116.57{\pm}5.72$, $138.40{\pm}5.91$, $212.88{\pm}4.82$, $361.00{\pm}9.72$, $577.50{\pm}42.86$, $743.75{\pm}24.65$, $1086.00{\pm}26.02$, $1402.00{\pm}24.54$ and $1432.00{\pm}27.00$ g respectively. Finally, this phenotypic characterization as well as productive and reproductive performances of Aseel chicken will give the baseline information to researcher for further study and for planning any on-ward conservation and implement strategy.

• Reproductive and Developmental Biology
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• v.37 no.3
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• pp.123-127
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• 2013

The objective of this study was to compare the effects of the levels of inbreeding on body weight traits between two breed populations, Hanwoo and Korea Brindle cattle. Birth weight (BW), weaning weight (WW), body weight at 6 months of age (W6) and yearling weight (YW). Records of 1,745 calves (1,513 from Hanwoo, and 232 from Korea Brindle calves) were collected from Livestock Research Institutes in Kangwon, Gyeongbuk and Chungbuk provinces. The least squares means (LSM) and their standard errors for BW, WW, W6 and YW were $25.4{\pm}0.1$ kg, $81.0{\pm}1.8$ kg, $146.1{\pm}3.7$ kg and $291.5{\pm}2.4$ kg, respectively in Hanwoo calves and $22.6{\pm}0.3$ kg, $79.9{\pm}2.3$ kg, $137.6{\pm}4.6$ kg and $249.3{\pm}6.6$ kg, respectively in Korea Brindle calves. Pedigree data showed that 14.8% (316 out of 2131) of Hanwoo was inbred and the average inbreeding coefficient was 0.0209 (2.09%). Inbreeding coefficients of ten calves out of 316 total inbred Hanwoo calves were 12.5% or higher, whereas those of the other 306 calves were less than 12.5%. In both breeds, calves were divided into three groups of inbreeding classes - highly inbred group($F{\geq}0.125$), lowly to medially inbred group(0

• Korean journal of applied entomology
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• v.42 no.4
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• pp.367-381
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• 2003

Dispersal polymorphism in insects Is a kind of adaptive strategy of the life history together with the diapause, consisting of the “long-winged or alate forms” of migratory phase and the “short-winged or apterous forms” of stationary phase. Dispersal polymorphism is a polymorphism related with the flight capability, and has three categories ; the wing polymorphisms, flight muscle polymorphisms, and flight behavior variations. Phase variation is another type of dispersal polymorphism varying in morphology, physiology and wing forms in response to the density of the population. The dispersal migration is a very adaptive trait that enables a species to keep pace with the changing mosaic of its habitat, but requires some costs. In general, wing reduction has a positive effect on the reproductive potential such as earlier reproduction and larger fecundity The dispersal polymorphism is a kind of optimization in the evolutionary strategies of the life history in insects; a trade-off between the advantages and disadvantages of migration. Wing polymorphism is a phenotypically plastic trait. Wing form changes with the environmental conditions even though the species is the same. Various environmental factors have an effect on the dispersal polymorphisms. Density dependent dispersal polymorphism plays an important role In population dynamics, but it is not a simple function of the density; the individuals of a population may be different in response to the density resulting different outcomes in the population biology, and the detailed information on the genotypic variation of the individuals in the population is the fundamental importance in the prediction of the population performances in a given environment. In conclusion, the studies on the dispersal polymorphisms are a complicated field in relation with both physiology and ecology, and studies on the ecological and quantitative genetics have indeed contributed to understanding of its important nature. But the final factors of evolution; the mechanisms of natural selections, might be revealed through the studies on the population biology.

• Journal of The Korean Association For Science Education
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• v.35 no.4
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• pp.691-707
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• 2015

This study aims to develop biology teachers' education program based on argumentation activity about core concepts of evolution and to analyze the characteristics of core concepts of evolution learned during the program. The eight core concepts of evolution in this study were variation, heritability of variation, competition, natural selection, adaptation, differential reproductive rate of individuals, changes in genetic pool within a population, and macroevolution. The performances of teachers participating in the program were compared before and after argumentation activities; consisting of seven sessions on the eight core concepts of evolution. The process of the program was specially designed by learning cycle model for teacher education, consisting of seven phases: identification of the task, production of a tentative argument, small group's written argument, share arguments with the other groups, reflective discussion, final written argument, and organization by an instructor. Participants in the study were two pre-service biology teachers and four in-service biology teachers. The results suggest that biology teachers reduced the teleological explanation for biological evolution and improve its adequacy after the intervention. Teachers lacked the opportunity to discuss variation, heritability of variation, competition, and macroevolution because science textbooks lack information on the concepts of biological evolution. The results of this study suggest that because the argumentation program developed for teachers helps to improve understanding the concepts of evolution and to reduce inadequate conceptions in biology, teacher education programs using argumentation activity and eight core concepts of evolution will play a role for efficient evolution education for biology teachers.