• Asian-Australasian Journal of Animal Sciences
• /
• 제6권2호
• /
• pp.275-279
• /
• 1993

A study using dairy heifers was conducted to determine the effect of environmental temperature on heat production differing in feed intake level. The design consisted of three levels of feed intake (low, medium and high) and two environmental chamber temperature (15 and $30^{\circ}C$) with four replications in each treatment. Rectal temperature (RT), respiration rate (RR), heart rate (HR) and heat production (HP) were then measured. At the both environmental temperature, RT, RR and HR increased with the increase in feed intake level. The RT and RR also increased with the elevation of environmental temperature. The HP of $30^{\circ}C$ was significantly higher (4.8-8.9%) than $15^{\circ}C$. The estimated metabolizable energy requirement for maintenance (MEm) was higher (p<0.05) at $30^{\circ}C$ ($554.7kJ/kg^{0.75}$ d) than $15^{\circ}C$ (464.9 kJ/kgd). It was suggested that the decreasing in productive efficiency under hot environmental conditions partly associated with the increase in HP, which associated with the change in heat loss mechanism from sensible path to evaporative path.

• Asian-Australasian Journal of Animal Sciences
• /
• 제3권1호
• /
• pp.47-52
• /
• 1990

During prolonged exposure to the sun for 8 h each day for 10 days in which the highest ambient temperature around 14:00 h was $39^{\circ}C$, buffaloes exposed to the sun without shade increased the turnover of body water by 35% and 76% on day 5 and day 10 of exposure respectively. The total body water markedly decreased on day five and this amount was maintained thereafter. Plasma and blood volumes did not change significantly on day five but markedly decreased on day 10. Packed cell volume significantly decreased on day five and day 10 of the exposure period. The reduction of packed cell volume on day 10 coincided with the decrease in total plasma water. On day 10 of the exposure, an increase in the rate of liquid flow from the rumen was noted. It is concluded that on the fifth day of exposure, the increase in the evaporative cooling process was attributed to initial mobilization of water from the intracellular compartment. The reduction of both plasma and cell volumes occurring from day five to day 10 indicated a loss of body water from both intracellular and extracellular compartments.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제12권2호
• /
• pp.75-80
• /
• 2006

Changes in the levels of protein and free amino acids in the haemolymph of three selected races of the silkworm, Bombyx mori viz., PM, $NB_4D_2$ and $CSR_2$, were investigated during 4th moult, 5th instar and pupal period. The levels of total protein in the haemolymph, increased from first day of 5th instar till sixth day. From seventh day till spinning, the protein levels decreased in all the three races. A sustained decrease in the haemolymph proteins was observed during the pupal development in all the three races. The levels of free amino acids, which were high during 4th moult, declined through the 5th age of larval development till spinning. PM showed a relatively higher free amino acid level (3.192 mg/ml) in haemolymph followed by $NB_4D_2$ (2.601 mg/ml) and $CSR_2$ (2.35 mg/ml). The free amino acid levels decreased gradually from prepupal stage but increased again at the end of pupal period. Racial differences in the changes in the levels of protein and free amino acids in the haemolymph were observed in the larvae and pupae when subjected to two high temperature regimes of $30^{\circ}C$ and $35^{\circ}C$. The results showed that high temperature induces specific changes in the metabolism (reversible thermal stress) that have different adaptive value in different races of the silkworm. Relatively higher increase in the free amino acid levels in the haemolymph of Pure Mysore presumably provides protective cover to tissues against high temperature by an increase in osmolarity and reduction in evaporative water loss. The absence of such a mechanism may be responsible for temperature susceptibility of the bivoltine races like $NB_4D_2$ and $CSR_2$.

• 한국토양비료학회지
• /
• 제45권4호
• /
• pp.484-491
• /
• 2012

The hydrological components of a sandy loam soil of nearly level in Chuncheon over 30 years were computed using the E-DiGOR model. Daily simulations were carried out for each year during the period of 1980 to 2009 using standard climate data. Reference evapotranspiration and potential soil evaporation based on Penman-Montheith model were higher during May to August because of the higher atmospheric evaporative demand. Actual soil evaporation was mainly found to be a function of the amount and timing of rainfall, and presumably soil wetness in addition to atmospheric demand. Drainage was affected by rainfall and increased with a higher amount of precipitation and soil water content. Excess drainage occurred throughout rainy months (from July to September), with a peak in July. Therefore, leaching may be a serious problem in the soils all through these months. The 30-year average annual reference evapotranspiration and potential soil evaporation were 951.5 mm and 714.2 mm, respectively. The actual evaporation from bare soil varied between 396.9-528.4 mm and showed comparatively lesser inter-annual variations than drainage. Annual drainage rates below 120 cm soil depth ranged from 477.8 to 1565.9 mm. The long-term mean annual drainage-loss was approximately two times higher than actual soil evaporation.

• 한국물환경학회지
• /
• 제30권6호
• /
• pp.673-682
• /
• 2014

A watershed model was constructed using Hydrological Simulation Program Fortran to predict the water temperature at major tributaries of Nakdong River basin, Korea. Water temperature is one of the most fundamental indices used to determine the nature of an aquatic environment. Most processes of an aquatic environment such as saturation level of dissolved oxygen, the decay rate of organic matter, the growth rate of phytoplankton and zooplankton are affected by temperature. The heat flux to major reservoirs and tributaries was analyzed to simulate water temperature accurately using HSPF model. The annual mean heat flux of solar radiation was estimated to $150{\sim}165W/m^2$, longwave radiation to $-48{\sim}-113W/m^2$, evaporative heat loss to $-39{\sim}-115W/m^2$, sensible heat flux to $-13{\sim}-22W/m^2$, precipitation heat flux to $2{\sim}4W/m^2$, bed heat flux to $-24{\sim}22W/m^2$ respectively. The model was calibrated at major reservoir and tributaries for a three-year period (2008 to 2010). The deviation values (Dv) of water temperature ranged from -6.0 to 3.7%, Nash-Sutcliffe efficiency(NSE) of 0.88 to 0.95, root mean square error(RMSE) of $1.7{\sim}2.8^{\circ}C$. The operational water temperature forecasting results presented in this study were in good agreement with measured data and had a similar accuracy with model calibration results.

• Asian-Australasian Journal of Animal Sciences
• /
• 제7권3호
• /
• pp.357-362
• /
• 1994

Five adult sheep were exposed to intermittent cold for 12 h (18:00-06:00) at an air temperature of $5{\pm}1^{\circ}C$ followed by 12 h (06:00-18:00) at $25{\pm}2^{\circ}C$ over a period of 8 days continuously. Carotid artery blood (Tc), mean skin (Ts) and mean body (Tb = 0.86 Tc + 0.14 Ts) temperatures, heat production rate (HP), respiratory evaporative heat loss, respiration rate (RR) and volume were measured before and after exposure. Tc during the 12 h cold period of intermittent cold exposure was similar to that during the corresponding period in the warm environment, while Tc in the $25^{\circ}C$ of intermittent cold was higher (p < 0.05) than that in the corresponding period in the warm environment. Ts during the cold period markedly decreased (p < 0.001) by about $9^{\circ}C$ when compared with that in the corresponding time period in the warm environment, while Ts during the $25^{\circ}C$ period of intermittent cold recovered to a similar level to that in the warm environment. Tb was lower (p < 0.001) during the cold period of intermittent cold, whereas a slight increase in Tb during the $25^{\circ}C$ period of intermittent cold was significant (p < 0.05) when compared with the value during the similar period in the warm environment. HP was greatly increased (p < 0.001) by cold exposure, followed by an immediate decrease during the first one hour of the 12 h warm period, reaching a similar level to that in the warm environment. A lower (p < 0.05) RR was observed during both the cold and $25^{\circ}C$ period of intermittent cold than during the corresponding periods in the warm environment. The results of the present investigation clearly show that the body temperature of sheep increased during a 12 h warm period following 12 h of exposure to cold. These results suggest that during a warm period of an intermittent cold exposure cycle, heat could be shored in the animal body.

• Asian-Australasian Journal of Animal Sciences
• /
• 제10권6호
• /
• pp.652-656
• /
• 1997

This study was conducted to determine the relationships between abdominal temperature (Tabd) and some thermoregulatory responses, such as heat production (HP), heart rate (HR), respiration rate (RR), temperature of external ear tract (Tee), comb surface temperature (Tcs) and shank skin temperature (Tss), for revealing the role of deep body temperature in the thermoregulation of broiler chickens. Tabd was divided into 5 zones of 40-41, 41-42, 42-43, 43-44 and $44-45^{\circ}C$, and maintained for 3 hours in each zone by varying environmental temperature from 11 to $33^{\circ}C$. HP and HR had a greater increase with Tabd above $42.5^{\circ}C$. RR increased markedly with Tabd above $41.5^{\circ}C$, and reached a maximum when Tabd was at $42.5^{\circ}C$, then began to decrease. In addition, HP and HR increased significantly with decrease RR during the decreasing phase of panting. Tcs and Tss changed rapidly with Tabd when Tabd was below $41.5^{\circ}C$, and increased more slowly above $41.5^{\circ}C$. Tee was lower than Tabd, and its increase was less than that of Tabd. These results suggest that changes in thermoregulatory responses are induced by an increase in abdominal temperature. Tabd increases to adjust the ratio of sensible and evaporative heat loss when Tabd is below $42.5^{\circ}C$, while the ability in body temperature regulation gradually disappears when abdominal temperature exceeds $42.5^{\circ}C$ and heat balance can not be maintained.

• The Korean Journal of Physiology and Pharmacology
• /
• 제19권1호
• /
• pp.9-14
• /
• 2015

We investigated the sweating response during passive heating (partial submersion up to the umbilical line in $42{\pm}0.5^{\circ}C$ water, 30 min) after summer and winter seasonal acclimatization (SA). Testing was performed in July during the summer, 2011 [summer-SA; temp, $25.6{\pm}1.8^{\circ}C;$ relative humidity (RH), $82.1{\pm}8.2%$] and in January during the winter, 2012 (winter-SA; temp, $-2.7{\pm}2.9^{\circ};$ RH, $65.0{\pm}13.1%$) in Cheonan ($126^{\circ}52^{\prime}N$, 33.38'E), Republic of Korea. All experiments were carried out in an automated climatic chamber (temp, $25.0{\pm}0.5^{\circ}C$: RH, $60.0{\pm}3.0%$). Fifteen healthy men (age, $23.4{\pm}2.5$ years; height, $175.0{\pm}5.9cm;$ weight, $65.3{\pm}6.1kg$) participated in the study. Local sweat onset time was delayed during winter-SA compared to that after summer-SA (p<0.001). Local sweat volume, whole body sweat volume, and evaporative loss volume decreased significantly after winter-SA compared to those after summer-SA (p<0.001). Changes in basal metabolic rate increased significantly after winter-SA (p<0.001), and tympanic temperature and mean body temperature were significantly lower after summer-SA (p<0.05). In conclusion, central sudomotor acitivity becomes sensitive to summer-SA and blunt to winter-SA in Rebubic of Korea. These results suggest that the body adjusts its temperature by economically controlling the sweating rate but does not lower the thermal dissipation rate through a more effective evaporation scheme after summer-SA than that after winter-SA.

• 원예과학기술지
• /
• 제29권1호
• /
• pp.16-22
• /
• 2011

Polyoxyethylene nonylphenyl ether와 polyoxyethylene castor oil을 1:1(v/v)로 혼합하여 조제한 액상 토양습윤제(LWA)가 피트모스 + 펄라이트(7:3) 상토내 잔류성, 혼합상토의 초기 습윤화 및 고추(Capsicum annuum L. 'Knockwang') 플러그묘의 생육에 미치는 영향을 구명하고자 본 연구를 수행하였다. 토양습윤제의 처리량이 증가할수록 상토의 보수량이 뚜렷하게 증가하였고 본 연구에서 제조한 토양습윤제를 $2.5mL{\cdot}L^{-1}$의 비율로 처리한 구의 보수량이 AquaGroL을 $3.0mL{\cdot}L^{-1}$을 처리한 +대조구와 유사하였다. 처리된 토양습윤제는 처리 후 1 및 2번째 관수에서 대부분 용탈되었고, 10회 관수할 때까지 서서히 낮아지다가 10회 관수 이후에는 매우 낮은 농도로 분석되었다. 개발된 토양습윤제를 처리한 상토에서 관수한 수분의 수직방향으로 하강 속도를 측정한 결과 0.5, 1.0, 및 $1.5mL{\cdot}L^{-1}$의 비율로 처리한 구에서 -대조구보다 월등히 빨랐으나, 토양습윤제의 처리비율이 $2.0mL{\cdot}L^{-1}$ 이상으로 높아지면 점차 느려지는 경향을 보였다. 습윤제를 처리한 상토를 충분히 관수하고 온실에서 상토의 건조속도를 조사한 결과 무처리구의 건조속도가 가장 빨랐고, 개발된 토양습윤제의 처리비율이 높아질수록 상토의 건조속도가 느렸다. 파종 8주 후에 조사한 고추 플러그 묘의 생육에서 초장은 $0.5mL{\cdot}L^{-1}$ 처리에서 22.2cm로 가장 컸고, 줄기직경은 $1.0mL{\cdot}L^{-1}$ 처리에서 3.46mm로 가장 굵었으며, 생체중과 건물중은 $1.0mL{\cdot}L^{-1}$ 처리구에서 각각 식물체당 3.08g과 0.861g으로 조사되어 다른 시험구에 비해 유의하게 우수하였다. 그러나 $1.5mL{\cdot}L^{-1}$ 이상으로 토양습윤제의 처리량이 높아지면 점차 생육이 저조하였으며, 적정 처리량은 $1.0mL{\cdot}L^{-1}$라고 판단하였다.

• 농업과학연구
• /
• 제4권2호
• /
• pp.317-343
• /
• 1977

분종류(盆種類)에 따른 수분증발량(水分蒸發量), 분내토양온도(盆內土壤溫度) 및 토양공기조성(土壤空氣組成)의 차(差)를 조사(調査)하고, 이들 조건(條件)이 분식물(盆植物)의 생육(生育)에 미치는 영향(影響)을 구명(究明)하기 위해 본(本) 실험(實驗)을 수행(遂行)하였다. 분종류(盆種類)는 토분(土盆)(CP), 도자기분(盆)(POP), 프라스틱분(盆)(PLP)을 사용(使用)하였으며, 토분(土盆)을 사용(使用)할 경우 수분증발량(水分蒸發量)을 감소시키기 위한 방법(方法)으로서 토분외벽(土盆外壁)에 녹색(綠色)페인트를 칠한 것(CP-P), 투명(透明)니스를 칠한 것(CP-V), 토분내면(土盆內面)에 polyethylene film을 깐 것(CP-PI) 및 토분(土盆)의 분토표면(盆土表面)을 흑색(黑色) polyethylene film으로 피복한 것(CP-PM) 등을 사용(使用)하였다. 공시식물(供試植物)로서는 봉선화, 국화(菊花), 코스모스, 양담장이, 제라늄, 코키아, 만수국(萬壽菊), 엽모단(葉牡丹) 및 샐비어등(等)을 사용(使用)하였다. 1. PLP, POP, CP-P, CP-V 및 CP-PI에서 자란 식물(植物)은 CP에서 자란 식물(植物)보다 건물중(乾物重)이 무거웠다. 2. 모든 공시식물(供試植物)의 초장(草長)은 PLP, POP, CP-P, CP-V 및 CP-PI에서는 CP에서 보다 컸다. 3. Geranium의 엽수(葉數)는 PLP, POP, CP-P 및 CP-V는 CP에 비(比)해 많았다. 4. Balsam의 전생육기간중(全生育期間中)의 개화수(開花數)는 PLP, CP-P, POP, CP-V 및 CP-PI는 CP에 비(比)해 많았다. Marigold는 balsam과 비슷한 경향(傾向)을 나타내었으며, salvia는 화수수(花穗數)는 차(差)가 없으나 화수장(花穗長) 및 소화수(小花數)는 balsam 및 marigold의 개화수(開花數)와 동일(同一)한 경향(傾向)을 나타내었다. 5. PLP와 POP의 1일(日) 평균(平均) 증발량(蒸發量)은 CP의 약(約) 43%였으며, CP는 총증발량(總蒸發量)의 2/3가 벽면(壁面)을 통(通)해 증발(蒸發)되었다. 6. 분(盆)으로부터의 수분증발율(水分蒸發率)은 PLP, POP, CP-P, CP-V, CP-PI, CP-PM 및 CP의 순으로 늦었으며, 수분함량(水分含量)은 벽면증발(壁面蒸發)이 억제(抑制)된 분(盆)에서 관수(灌水) 1일후(日后)부터 CP보다 많았다. 7. 분토(盆土)의 온도(溫度)는 증발량(蒸發量)이 많은 분(盆)일수록 낮았으며, 분종류(盆種類)에 따른 온도차(溫度差)는 주간(晝間)에는 컷으나 야간(夜間)에는 적었다. 8. 분토중(盆土中)의 산소농도(酸素濃度)는 무공성분(無孔性盆)이 CP에 비(比)해 약간 낮았고, 그 차이(差異)는 0.40~1.2%였으며, 산소농도(酸素濃度)의 범위는 17.95~19.62%였다. 탄산(炭酸)깨스농도(濃度)는 무공성분(無孔性盆)이 토분(土盆)보다 높았으며, 농도(濃度)범위는 0.59~1.76%였는데 이 범위의 공기조성(空氣組成)은 식물생육(植物生育)에 아무런 영향을 미치지 않았다. 9. 분토(盆土)의 수분함량(水分含量)과 식물생육간(植物生育間)에는 정(正)의 상관(相關)을 나타내었다. 10. CP에 재배(栽培)한 식물(植物)은 PLP에 재배(栽培)한 식물(植物)보다 지상부중(地上部中)의 총질소함량(總窒素含量)이 약간 많았으며 C/N율(率)이 다소 낮은 경향(傾向)을 나타내었다. 이러한 결과(結果)로 보아 분내토양공기중(盆內土壤空氣中)의 산소(酸素) 및 탄산(炭酸)깨스농도(濃度)는 분식물(盆植物)의 생육(生育)을 조해(阻害)할 정도로 낮아지거나 높아지지 않아서 분식물(盆植物)의 생육(生育)에 영향(影響)을 미치지 않으며, 벽면증발량(壁面蒸發量)의 다소(多少)에 따른 분내토양중(盆內土壤中)의 수분함량(水分含量)의 변화(變化)가 분식물(盆植物)의 생육(生育)에 가장 큰 영향(影響)을 미치므로 무공성분(無孔性盆)의 이용(利用)은 특(特)히 우리나라에서 관수노력(灌水勞力)을 절약(節約)할 수 있어서 생산비절감(生産費節減)을 가져올 수 있다.