• Journal of Environmental Science International
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• v.26 no.7
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• pp.817-826
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• 2017

We analyzed how foraging area use changed in female Pipistrellus abramus during the breeding season. Radio tracking was used to follow 12 female P. abramus in Gyeongju City, from 2013 to 2015. We followed three bats in each of four stages of reproduction: early pregnancy, late pregnancy, lactation, and post-lactation. Our data showed that the usable area of a foraging site and the area that was actually used by bats in that site were different, and foraging site use also differed according to stage of reproduction. The bats used arable land the most, with use rates of 57%, 40.4%, and 73.2% during early pregnancy, late pregnancy, and lactation, respectively. Bats in a post-lactation state did not use arable areas at all and instead foraged over bodies of water 90% of the time. There was no difference in the use of each foraging environment between bats in early pregnancy and late pregnancy. However, bats in late pregnancy and those that were lactating did use arable land to different extents, and bats that were lactating and those that were post-lactation also used arable land and bodies of water to different extents.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.1-9
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• 2011

In order to analyze the change in home ranges depending on the reproductive stage of Pipistrellus abramus, radio-tracking was carried out for a total of 9 individuals, 3 individuals each, by dividing stages into a pregnancy stage, lactation stage, and post-lactation stage from May to August 2009. For radio-telemetry, 0.38g transmitters, R2000 receivers and 3-element Yagi antennas were used. Pipistrellus abramus were captured using a double-stacked mist net and a harp-trap. Analysis of home ranges used a SHP File and ArcGIS 3.3 for GIS, and used a Kernel Home Range Method(KHR) and a Minimum Convex Polygon(MCP) Method for analysis. Home ranges at the pregnancy stage were MCP 100% $13.46{\pm}1.84ha$, MCP 95% $12.28{\pm}2.15ha$, KHR 50% $3.00{\pm}0.71ha$, and home ranges at the lactation stage were MCP 100% $8.13{\pm}0.23ha$, MCP 95% $7.73{\pm}0.63ha$, KHR 50%$1.84{\pm}1.05ha$. Home ranges at the post-lactation stage were MCP 100% $125.58{\pm}97.77ha$, MCP 95% $123.89{\pm}97.73ha$, KHR 50% $28.61{\pm}26.78ha$. As a result, home ranges of pipistrellus abramus showed a significant difference in all of the MCP 100%, MCP 95%, KHR 50% depending on reproductive stages, being largest in the post-lactation stage and smallest in the lactation stage.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.208-215
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• 2003

Bisphenol A (4,4'-isopropylidenediphenol, $C^{15}H_{16}O_{2}$) is the monomer used in the manufacture of polycarbonate. Polycarbonate, in turn, is used in a wide array of plastic products, with new applications continuously being developed. Also it has been used to produce epoxy resins and polycarbonate plastics for food container. This study was carried out to investigate the effects of bisphenol A on lactation period to dams and F1. Sprague-Dawley females were mated with on 2 : 1 ratio basis. Various doses of bisphenol A (0, 2, 20, 200, and 2,000 ${\mu}g kg^{-1}$) were daily administered to females for 21 days after parturition. Dams and offsprings were sacrificed at the time of weaning. The results were as fellows, 2000 ${\mu}g \; kg^{-1}$ / of bisphenol A decreased the dams' body weight at post-partum 18 days and also 200 and 2,000 ${\mu}g \;kg^{-1}$ of bisphenol A decreased the body weight of neonates at the days of post-partum 21 days. Bisphenol A increased the relative weights of liver and spleen in male offsprings, depending on the doses. But female offsprings showed high relative organ weights of ovaries, and low relative organ weights of uterine in a some dose-response manners. High dose of bisphenol A induced low viability of neonates exposed during lactation period. The dams treated with bisphenol A showed prematured estrous stage. Bisphenol A was recovered about 21.2% average in serum of dams, and also in offsprings'. The results indicate that the bisphenol A induces estrous cycle during lactation period in dams, also reaches to the offspring through breast milk. Thus bisphenol A exopsed to dams and neonates via lactation induces some estrogenic and tonic effects.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.171-173
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• 2003

Bisphenol A (4,4'-isopropylidenediphenol, C$\_$15/H$\_$16/O$_2$) is the monomer used in the manufacture of polycarbonate. Polycarbonate, in turn, is used in a wide array of plastic products, with new applications continuously being developed. Also it has been used to produce epoxy resins and polycarbonate plastics for food container. This study was carried out to investigate the effects of bisphenol A on lactation period to dams and F1, Sprague-Dawley females were mated with on 2:1 ratio basis. Various doses of bisphenol A (0, 2, 20, 200, and 2,000 $\mu\textrm{g}$/kg) were daily administered to females for 21 days after parturition. Dams and offsprings were sacrificed at the time of weaning. The results were as follows, 2000 $\mu\textrm{g}$/kg of bisphenol A decreased the dams' body weight at post-partum 18 days and also 200 and 2000 $\mu\textrm{g}$/kg of bisphenol A decreased the body weight of neonates at the days of post-partum 21 days. Bisphenol A increased the relative weights of liver and spleen in male offsprings, depending on the doses. But female offsprings showed high relative organ weights of ovaries, and low relative organ weights of uterine in a some dose-response manners. High dose of bisphenol A induced low viability of neonates exposed during lactation period. The dams treated with bisphenol A showed prematured estrous stage. Bisphenol A was recovered about 21.2% average in serum of dams, and also in offsprings'. The results indicate that the bisphenol A induces estrous cycle during lactation period in dams, also reaches to the of offspring through breast milk. Thus bisphenol A exopsed to dams and neonates via lactation induces some estrogenic and toxic effects.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.4
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• pp.523-531
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• 2008

Buffalo are a major source of milk production, contributing 12.1% in the World and 38.0% in Asia. The buffaloes are kept under peri-urban farming systems to produce milk for urban populations. Breeding is delayed in these herds to get more economic benefit because farmers believe that the pregnancy decreases milk production. The lactation milk value has been studied in this paper as an economic indicator. Complete milk yield records of 3,304 buffaloes was collected from a group of state farms. Economic traits including lactation yield, lactation length, calving interval (CI), dry period and milk yield per day of calving interval (MYPDCI) were derived from the data. The animals were grouped according to parity number (1-3), service period (G1 to G4, conceiving during <150, 150-200, 200-300 and >300 days post calving) and yield levels (HMY>2,500; MMY 2,001-2,500; and LMY 1,500-2,000 liters/ lactation). To study the effect of pregnancy on milk composition a research trial was conducted at a medium size private dairy farm, using forty lactating buffaloes of three yield levels and four service period groups, as described already. Milk was sampled on alternate weeks and analyzed for fat and protein contents (%). For quantifying the value of milk produced during a lactation period, the value corrected milk (VCM) was determined and converted to lactation milk value (LMV). Group means were compared for varicous parameters. Highest milk yield ($2,836.50{\pm}15.68$ liters/lactation) was recorded in the HMY animals of G4 group while lowest milk yield of $1,657.04{\pm}8.34$ liters/lactation was found in LMY of G1. Lactation was significantly increased with the extending of service period. The shortest dry period was recorded in HMY, parity 1, G1 animals and the longest in parity 2, MMY, G4.The CI was shortest in HMY, parity 1, and G1 animals and longest in LMY, parity 3, G4 buffaloes. The HMY, parity 2, G1 buffaloes showed the highest MYPDCI and the lowest value was recorded ($6.53{\pm}0.17$ vs. $2.76{\pm}0.04$ liter/day) for LMY, parity 1, G4 buffaloes. The VCM decreased with the delayed conception. This decreasing trend was higher in respect of the total yield but decrease in the VCM was smaller due to the increasing levels of fat and protein in the milk. The gap between the various production classes was reduced based on the VCM as compared with the yield per day of CI. LMV showed a consistent decline with extending service period in all three production groups. The study suggests that CI increased with delayed conception, showing a consistent trend in the low, moderate and high yielding buffaloes. There was a coherent declining pattern of milk yield with delaying conception, associated with prolonged CI. An animal conceiving at a later stage of lactation showed a decline in financial returns of 24 to 27% compared with those conceiving earlier.

• Animal Bioscience
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• v.34 no.4
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• pp.539-545
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• 2021

Objective: Endometritis is a major disease, that causes infertility in cattle, and is usually categorized as clinical or subclinical endometritis (SCE). The nutritional condition during the dry period is important for recovery after the last stage of the lactation period, and for postpartum production and reproduction. This study aimed to clarify the relationship between nutritional and metabolic characteristics in the dry period, and the risk of postpartum SCE. Methods: Multiparous Holstein dairy cows (n = 25, raised in a tied stall) were used. Endometrial cytological analysis was performed around 30 days post-partum, with 5% to 14% polymorphonuclear (PMN) as a cut-off point to define SCE. Serum levels of glucose, non-esterified fatty acids, β-hydroxybutyric acid (BHBA), blood urea nitrogen, total cholesterol, aspartate aminotransferase, γ-glutamyl transpeptidase, calcium, phosphorus, and magnesium were measured in the cows at the dry period to evaluate energy status, protein metabolism, and mineral metabolism. Results: The incidence of SCE in the cows was 60.0% (n = 15/25) and the mean PMN% in postpartum cows diagnosed as SCE was 8.05%±2.6%. Overall, 17 and 8 samples were collected from the cows in the far-off and close-up periods, respectively. The serum concentration of BHBA in the far-off period and serum glucose concentration in the closeup period were correlated with postpartum PMN% (r = 0.62, p<0.01; r = -0.74, p<0.05, respectively). Serum levels of calcium and magnesium in the dry period were associated with the incidence of postpartum SCE (healthy vs SCE cows, p<0.05). Conclusion: Blood levels of glucose, BHBA, calcium, and magnesium in dry periods could be useful parameters for predicting the risk of postpartum SCE. The present study also suggests that management in the close-up period is essential for promoting recovery from calving fatigue.