• Title/Summary/Keyword: Withdrawal period

Search Result 140, Processing Time 0.027 seconds

Dynamic of heat production partitioning in rooster by indirect calorimetry

  • Rony Lizana, Riveros;Rosiane, de Sousa Camargos;Marcos, Macari;Matheus, de Paula Reis;Bruno Balbino, Leme;Nilva Kazue, Sakomura
    • Animal Bioscience
    • /
    • v.36 no.1
    • /
    • pp.75-83
    • /
    • 2023
  • Objective: The objective of this study was to describe a methodological procedure to quantify the heat production (HP) partitioning in basal metabolism or fasting heat production (FHP), heat production due to physical activity (HPA), and the thermic effect of feeding (TEF) in roosters. Methods: Eighteen 54-wk-old Hy Line Brown roosters (2.916±0.15 kg) were allocated in an open-circuit chamber of respirometry for O2 consumption (VO2), CO2 production (VCO2), and physical activity (PA) measurements, under environmental comfort conditions, following the protocol: adaptation (3 d), ad libitum feeding (1 d), and fasting conditions (1 d). The Brouwer equation was used to calculate the HP from VO2 and VCO2. The plateau-FHP (parameter L) was estimated through the broken line model: HP = U×(R-t)×I+L; I = 1 if t<R or I = 0 if t>R; Where the broken-point (R) was assigned as the time (t) that defined the difference between a short and long fasting period, I is conditional, and U is the decreasing rate after the feed was withdrawn. The HP components description was characterized by three events: ad libitum feeding and short and long fasting periods. Linear regression was adjusted between physical activity (PA) and HP to determine the HPA and to estimate the standardized FHP (st-FHP) as the intercept of PA = 0. Results: The time when plateau-FHP was reached at 11.7 h after withdrawal feed, with a mean value of 386 kJ/kg0.75/d, differing in 32 kJ from st-FHP (354 kJ/kg0.75/d). The slope of HP per unit of PA was 4.52 kJ/mV. The total HP in roosters partitioned into the st-FHP, termal effect of feeding (TEF), and HPA was 56.6%, 25.7%, and 17.7%, respectively. Conclusion: The FHP represents the largest fraction of energy expenditure in roosters, followed by the TEF. Furthermore, the PA increased the variation of HP measurements.

The anti-nociceptive effect of BPC-157 on the incisional pain model in rats

  • Jung, Young-Hoon;Kim, Haekyu;Kim, Hyaejin;Kim, Eunsoo;Baik, Jiseok;Kang, Hyunjong
    • Journal of Dental Anesthesia and Pain Medicine
    • /
    • v.22 no.2
    • /
    • pp.97-105
    • /
    • 2022
  • Background: The pentadecapeptide BPC-157 has been shown to have anti-inflammatory and wound healing effects on multiple target tissues and organs. Peptides have potent anti-inflammatory effects on periodontal tissues in rats with periodontitis. Few studies have investigated the effect of BPC-157 on pain after dental procedures or oral surgeries. The purpose of the present study was to investigate the antinociceptive effects of BPC-157 on postoperative incisional pain in rats. Methods: Sprague-Dawley rats were randomly divided into five groups: control (saline with the same volume), BPC10 (10 ㎍/kg of BPC-157), BPC20 (20 ㎍/kg of BPC-157), BPC40 (40 ㎍/kg of BPC-157), and morphine (5 mg/kg of morphine). A 1-cm longitudinal incision was made through the skin, fascia, and muscle of the plantar aspect of the hind paw in isoflurane-anesthetised rats. Withdrawal responses were measured using von Frey filaments at 0, 2, 6 h and 4, 7 d after incision. The formalin test was also performed to differentiate its anti-nociceptive effect from an inflammatory reaction or central sensitization. Pain behavior was quantified periodically in phases 1 and 2 by counting the number of flinches in the ipsilateral paw after injection with 30 µL of 5% formalin. Results: The threshold of mechanical allodynia was significantly increased in the BPC10, BPC20, BPC40 and morphine groups compared with that in the control group at 2 h. These increasing thresholds then returned to the levels of the control group. The BPC-157 group showed a much higher threshold at 4 days after incision than the control group. The thresholds of the BPC groups, except the morphine group, were normalized 7 days after incision. The flinching numbers of the BPC10, BPC20, BPC40 and morphine groups were significantly decreased in phase 1, but there was no decrease in the BPC-157 groups except the morphine group in phase 2. Conclusions: BPC-157 was effective only for a short period after incision. It was also effective during phase 1 but not during phase 2, as determined by the formalin test. BPC-157 might have a short antinociceptive effect, even though it has anti-inflammatory and wound healing effects.

Legislation on Aid in Dying in France (조력사망에 관한 프랑스의 입법 동향)

  • Jieun Lee
    • The Korean Society of Law and Medicine
    • /
    • v.25 no.1
    • /
    • pp.193-222
    • /
    • 2024
  • From a global trend, discussions on the patient's death with dignity are gradually progressing from the issue of withdrawal of life-sustaining treatment to the issue of whether to allow assisted death and its requirements. Several states in the United States and Western European countries such as Canada, Belgium, and the Netherlands have institutionalized treatment to accelerate the time of death through the assistance of doctors. In France, after a long period of raising and reviewing issues, discussions on related legislation are taking place at a slower pace than in other European countries. In France, social discussions and legislative attempts on death with dignity have been actively conducted since the late 20th century. The Leonetti Act of 2005 prohibited the continuation of meaningless treatment against the will of patients, and after the Clay-Leonetti Act of 2016, it was legalized to administer intensive and continuous sedatives to patients until death. However, unlike many neighboring European countries, treatment that speeds up the time of death itself is still prohibited in France, even if the patient wants. As the existential and universal question of whether to allow dying patients to die painlessly with the help of a doctor has recently emerged as an important issue, a number of lawmakers have submitted legislation to legalize assisted death. This paper examines the legislative process developed in relation to patients' rights to dignified death in France, and compares and reviews French legislation that attempts to legalize assisted death with the amendment to the Korean Life-Sustaining Treatment Act.

Serial Changes of Serum Thyroid-Stimulating Hormone after Total Thyroidectomy or Withdrawal of Suppressive Thyroxine Therapy in Patients with Differentiated Thyroid Cancer (분화성 갑상선 암 환자에서 갑상선 전절제술후 또는 갑상선 호르몬 억제 요법 중단에 따른 갑상선 자극호르몬의 변화)

  • Bae, Jin-Ho;Lee, Jae-Tae;Seo, Ji-Hyoung;Jeong, Shin-Young;Jung, Jin-Hyang;Park, Ho-Yong;Kim, Jung-Guk;Ahn, Byeong-Cheol;Sohn, Jin-Ho;Kim, Bo-Wan;Park, June-Sik;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
    • /
    • v.38 no.6
    • /
    • pp.516-521
    • /
    • 2004
  • Background: Radioactive iodine (RAI) therapy and whole-body scanning are the fundamentals of treatment and follow-up of patients with differentiated thyroid cancer. It is generally accepted that a Thyroid-Stimulating Hormone (TSH) level of at least 30 ${\mu}U/ml$ is a prerequisite for the effective use of RAI, and that it requires 4-6 weeks of off-thyroxine to attain these levels. Because thyroxine withdrawal and the consequent hypothyroidism are often poorly tolerated, and occasionally might be hazardous, it is important to be certain that these assumptions are correct. We have measured serial changes in serum TSH after total thyroidectomy or withdrawl of thyroxine in patients with thyroid cancer. Subjects and Methods: Serum TSH levels were measured weekly after thyroidectomy in 10 patients (group A) and after the discontinuation of thyroxine in 12 patients (group B). Symptoms and signs of hypothyroidism were also evaluated weekly by modified Billewicz diagnostic index. Results: By the second week, 78% of group A patients and 17% of group B patients had serum TSH levels ${\geq}30{\mu}U/ml$. By the third week, 89% of group A patients and 90% of group B patients had serum TSH levels ${\geq}30{\mu}U/ml$. By the fourth week, all patients in two groups achieved target TSH levels and there were no overt hypothyroidism. Conclusion: in all patients, serum TSH elevated to the target concentration (${\geq}30{\mu}U/ml$) within 4 weeks without significant manifestation of hypothyroidism. The schedule of RAI administration could be adjusted to fit the needs and circumstances of individual patients with a shorter preparation period than the conventional.

Study on the changes of sulfamethnzine residues in serum and practical organs of rats orally administrated with sulfamethnzine sodium (Rat에 sulfamethazine sodium 경구투여 후 혈청 및 실질장기내 sulfamethazine의 잔류량 추이에 관한 연구)

  • 도재철;이영미;조민희;신상희;박희주;송희종;정종식
    • Korean Journal of Veterinary Service
    • /
    • v.23 no.4
    • /
    • pp.321-333
    • /
    • 2000
  • In order to know the depletive changes of sulfamethazine residues in senlm and practical organs of rats orally administered with sulfamethazine sodium(SMS), the concentration of sulfamethazine was measured in serum and tissue(kidney, liver, spleen, testis, and skeletal muscle) of rats with using high performance liquid chromatography(HPLC). SMS was orally administrated to sprague-dawley male rats(body weight, 200~300g) with using sonde at the rate of 20mg/100g body weight(recommended therapeutic dose) on once a day for 3 days. There were investigated the depletive changes of the sulfamethazine in serum, kidney, liver, spleen, testis and skeletal muscle of rat at the time 8 hours, 1st, 2nd, 3rd, 4th, 5th and 6th day after administration SMS, respectively. The results obtained were summarized as follows; 1. After oral administration of the SMS, the mean concentrations of sulfamethazine in serum according to the time lapsed were showed 215.53$\pm$42.99ppm at the 8 hours after withdrawal of medicated sulfamethazine. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in serum were significantly (p<.05) decreased 25.87$\pm$5.18ppm at 1st day, 2.30$\pm$0.61ppm at 3rd day and 0.11$\pm$0.02ppm at 6th day respectively. 2. The mean concentrations of sulfamethazine in kidney, liver, spleen, muscle and testis according to the time lapsed after administration SMS were showed 83.82$\pm$12.16, 81.77$\pm$12.88, 36.96$\pm$5.35, 35.96$\pm$TEX>$\pm$1.39 and 27.89$\pm$1.92 ppm at the 8 hours, respectively. And gradually according to the time lapsed, the concentrations of sulfamethazine residues in the each of samples were significantly(p<.05) decreased such as 7.15$\pm$0.26, 5.62$\pm$0.72, 2.43$\pm$0.29, 1.99$\pm$0.14 and 3.11$\pm$0.48 ppm at 1st day, 0.52$\pm$0.04, 1.32$\pm$0.22, 0.13$\pm$0.03, 0.15$\pm$0.06 and 0.26$\pm$0.11ppm at 3rd day, and 0.03$\pm$0.01, 0.11$\pm$0.03, 0.02$\pm$0.01, 0.009$\pm$0.001 and 0.02$\pm$0.01 ppm at 6th day, respectively. 3. After oral administration of the SMS to rats, the residual concentrations of sulfamethazine in skeletal muscle were significantly (p<.05) decreased 35.96$\pm$1.39 to 0.009$\pm$$\pm$0.001 ppm between 8 hours and 6th day, respectively From the 4th day, the residual concentrations of sulfamethazine were showed 0.10$\pm$0.04 ppm below 0.1 ppm at the permitted limit concentration of muscle in Korea. In conclusion, this study could be suggested the relationship between administrated period, doses of sulfonamides and residual aspects of serum and practical organs, and the importance of observing ceasing period of antibiotic drugs before forwarding livestocks to slaughter.

  • PDF

우리나라의 출산력과 가정경제행태에 관한 연구

  • 노공균;조남훈
    • Korea journal of population studies
    • /
    • v.10 no.2
    • /
    • pp.17-45
    • /
    • 1987
  • This study contributes to understanding women's labor market behavior by focusing on a particular set of labor force transitions - labor force withdrawal and entry during the period surrounding the first birth of a child. In particular, this study provides a dynamic analyses, using longitudinal data and event history analysis, to conceptualize labor force behaviors in a straightforward way. The main research question addresses which factors increase or decrease the hazard rates of leaving and entering the labor market. This study used piecewise Gompertz model, following the guide of the non-parametric analysis on the hazard rates, which allowed relatively detailed description on the distribution of timing of leave and entry to the labor market as parameters of interest. The results show that preferences and structural variables, as well as economic considerations, are very important factors to explain the labor market behavior of women in the period surrounding childbirth.

  • PDF

The Effect of Structured Information on the Sleep Amount of Patients Undergoing Open Heart Surgery (계획된 간호 정보가 수면량에 미치는 영향에 관한 연구 -개심술 환자를 중심으로-)

  • 이소우
    • Journal of Korean Academy of Nursing
    • /
    • v.12 no.2
    • /
    • pp.1-26
    • /
    • 1982
  • The main purpose of this study was to test the effect of the structured information on the sleep amount of the patients undergoing open heart surgery. This study has specifically addressed to the Following two basic research questions: (1) Would the structed in formation influence in the reduction of sleep disturbance related to anxiety and Physical stress before and after the operation? and (2) that would be the effects of the structured information on the level of preoperative state anxiety, the hormonal change, and the degree of behavioral change in the patients undergoing an open heart surgery? A Quasi-experimental research was designed to answer these questions with one experimental group and one control group. Subjects in both groups were matched as closely as possible to avoid the effect of the differences inherent to the group characteristics, Baseline data were also. collected on both groups for 7 days prior to the experiment and found that subjects in both groups had comparable sleep patterns, trait anxiety, hormonal levels and behavioral level. A structured information as an experimental input was given to the subjects in the experimental group only. Data were collected and compared between the experimental group and the control group on the sleep amount of the consecutive pre and post operative days, on preoperative state anxiety level, and on hormonal and behavioral changes. To test the effectiveness of the structured information, two main hypotheses and three sub-hypotheses were formulated as follows; Main hypothesis 1: Experimental group which received structured information will have more sleep amount than control group without structured information in the night before the open heart surgery. Main hypothesis 2: Experimental group with structured information will have more sleep, amount than control group without structured information during the week following the open heart surgery Sub-hypothesis 1: Experimental group with structured information will be lower in the level of State anxiety than control group without structured information in the night before the open heart surgery. Sub-hypothesis 2 : Experimental group with structured information will have lower hormonal level than control group without stuctured information on the 5th day after the open heart surgery Sub-hypothesis 3: Experimental group with structured information will be lower in the behavioral change level than control group without structured information during the week after the open heart surgery. The research was conducted in a national university hospital in Seoul, Korea. The 53 Subjects who participated in the study were systematically divided into experimental group and control group which was decided by random sampling method. Among 53 subjects, 26 were placed in the experimental group and 27 in the control group. Instruments; (1) Structed information: Structured information as an independent variable was constructed by the researcher on the basis of Roy's adaptation model consisting of physiologic needs, self-concept, role function and interdependence needs as related to the sleep and of operational procedures. (2) Sleep amount measure: Sleep amount as main dependent variable was measured by trained nurses through observation on the basis of the established criteria, such as closed or open eyes, regular or irregular respiration, body movement, posture, responses to the light and question, facial expressions and self report after sleep. (3) State anxiety measure: State Anxiety as a sub-dependent variable was measured by Spi-elberger's STAI Anxiety scale, (4) Hormornal change measure: Hormone as a sub-dependent variable was measured by the cortisol level in plasma. (5) Behavior change measure: Behavior as a sub-dependent variable was measured by the Behavior and Mood Rating Scale by Wyatt. The data were collected over a period of four months, from June to October 1981, after the pretest period of two months. For the analysis of the data and test for the hypotheses, the t-test with mean differences and analysis of covariance was used. The result of the test for instruments show as follows: (1) STAI measurement for trait and state anxiety as analyzed by Cronbachs alpha coefficient analysis for item analysis and reliability showed the reliability level at r= .90 r= .91 respectively. (2) Behavior and Mood Rating Scale measurement was analyzed by means of Principal Component Analysis technique. Seven factors retained were anger, anxiety, hyperactivity, depression, bizarre behavior, suspicious behavior and emotional withdrawal. Cumulative percentage of each factor was 71.3%. The result of the test for hypotheses show as follows; (1) Main hypothesis, was not supported. The experimental group has 282 minutes of sleep as compared to the 255 minutes of sleep by the control group. Thus the sleep amount was higher in experimental group than in control group, however, the difference was not statistically significant at .05 level. (2) Main hypothesis 2 was not supported. The mean sleep amount of the experimental group and control group were 297 minutes and 278 minutes respectively Therefore, the experimental group had more sleep amount as compared to the control group, however, the difference was not statistically significant at .05 level. Thus, the main hypothesis 2 was not supported. (3) Sub-hypothesis 1 was not supported. The mean state anxiety of the experimental group and control group were 42.3, 43.9 in scores. Thus, the experimental group had slightly lower state anxiety level than control group, howe-ver, the difference was not statistically significant at .05 level. (4) Sub-hypothesis 2 was not supported. . The mean hormonal level of the experimental group and control group were 338 ㎍ and 440 ㎍ respectively. Thus, the experimental group showed decreased hormonal level than the control group, however, the difference was not statistically significant at .05 level. (5) Sub-hypothesis 3 was supported. The mean behavioral level of the experimental group and control group were 29.60 and 32.00 respectively in score. Thus, the experimental group showed lower behavioral change level than the control group. The difference was statistically significant at .05 level. In summary, the structured information did not influence the sleep amount, state anxiety or hormonal level of the subjects undergoing an open heart surgery at a statistically significant level, however, it showed a definite trends in their relationships, not least to mention its significant effect shown on behavioral change level. It can further be speculated that a great degree of individual differences in the variables such as sleep amount, state anxiety and fluctuation in hormonal level may partly be responsible for the statistical insensitivity to the experimentation.

  • PDF

Effect of Oxytetracycline Injection an the Body of Paralichthys Olivaceus (Oxytetracycline의 투여방법에 따른 넙치(Paralichthys olivaceus) 체내의 잔류 특성)

  • Ko, Chang-Sik;Kim, Dong-Hwi;Park, So-Hyun;Moon, Kyung-Mi;Heo, Moon-Soo
    • Journal of Life Science
    • /
    • v.26 no.3
    • /
    • pp.309-317
    • /
    • 2016
  • Industrial advancements have resulted in food culture development, followed by increased seafood consumption and large-scale seafood farming, which has been accompanied by an increased prevalence of fish disease. The antibiotic oxytetracycline (OTC) is commonly used to prevent and treat bacterial diseases in fish. However, overuse of OTC had led to negative aspects. In view of this, we conducted a research with regard to aspects of remnants on olive flounder skin, liver, and muscle through dipping treatment and oral feeding of OTC and analyzed the results with bioassay and HPLC quantitative analyses. The dipping treatment was carried out once with 25 g/ton/hr of OTC, and the oral treatment with 62.5 mg/kg body weight/7 days. The results underwent a bioassay analysis. The dipping group reacted only on the skin right after dipping, while the oral feeding group responded on the skin for 77 days after feeding and on the muscle for 14 days. In the dipping group, the HPLC quantitative analysis revealed remnants in the skin on the 37th day and on the 13th day in the liver group. No remnants were found in the muscle, even immediately after dipping. In the oral feeding group, there was a high concentration (1.07 mg/kg) of remnant in the skin, even on the 77th day. 0.56 mg/kg in the liver, even a small amount, and no remnant in the muscle on the 42nd day. To sum up, the results suggest that it will not be harmful to our body to observe the OTC withdrawal period of 40 days with the muscle because OTC will hardly remain on it. When using olive flounder for sashimi, the skin and liver should not be used for broth, as the quantity of OTC residue is several times higher than that found in muscle. As previous studies reported that the concentration of remnants gradually decreased with heating, so it was likely to lessen, depending on the cooking temperature.

The Seosan County Family Planning/Maternal & Child Health Service Research Project, Korea -Project Design and Findings of the Baseline Survey- (가족계획(家族計劃) 및 모자보건사업(母子保健事業)의 효율적 통합방안(統合方案)에 관한 연구(硏究)(서산군(瑞山郡)) -기초조사보고(基礎調査報告)-)

  • Bang, S.;Cho, T.H.;Lee, S.J.;Han, S.H.;Lim, K.J.;Ahn, M.Y.
    • Journal of Preventive Medicine and Public Health
    • /
    • v.16 no.1
    • /
    • pp.163-192
    • /
    • 1983
  • In order to facilitate the Korean government's efforts in integrating family planning and maternal & child health at the primary health care level (or township level), the Soon Chun Hyang College of Medicine, with the financial and technical assistance of WHO, has under-taken a service research project. The project has employed a quasi-experimental study design introducing interventions tat provide crucial factors lacking in the ongoing government programs such as midwives and qualified referral physicians. The study is being conducted in three locations, one control area and two study areas. Before introducing trained Nurse/Midewives into the study areas, a baseline prevalence survey was undertaken from 15 July 1981 to 10 August 1981 in selelcted townships of Seosan County. In this sample survey of bath the study and control areas, 2,484 eligible women (97% reponse rate) were interviewed to obtain benchmark data on basic evaluation indicators related to family planning and maternal and child health. The salients results were summarized as follows.: 1. CONTACT RATES WITH HEALTH WORKERS; During the year preceding the survey, 12% of women were visited by government health workers. The primary reason for such visits by health workers was family planning (45% of the visits). About 34% of the women visited the health centers during the year. The primary reason for visiting health centers was immunizations for their children (45% of the visits). 3. FAMILY PLANNING USE RATE; The baseline data showed little difference between women in the study area and the control area on contraceptive use. Approximately 59% were currently using some methods. However, among those current users, almost half were practicing less effective methods of birth control such as rhythm or withdrawal. Among other methods, the tubectomy was the most popular (16%), while use of the IUD, oral pill and condom together reached only 14%. 3. PRENATAL CARE RATE; About 75% of the women reported no prenatal care for their last births (the youngest child of each women), Additionally, among women received prenatal care, over half had only one visit. 4. ATTENDANCE AT DELIVERY; Most of the women surveyed (over 80%) were attended by a non-medical person during their last delivery. These figures are somewhat comparable to the national figure of 84% for remote areas. 5. POSTNATAL CARE; The proportion of women reporting postnatal care was only 4.5%, and postnatal care was not received by the majority of women surveyed. 6. CHILD HEALTH CARE: In contrast to the low rate of maternity care for women themselves, most women reported obtaining immunization care for their children. About 75% of the women obtained Polio and/or DPT, 58% BCG, and 44% Measles vaccine for their children. However, in terms of illness care, while 35% of the women stated that their youngest child had been sick during the month preceding the survey, only 28% of these women took their child to the clinic for treatment. 7. COMPLICATIONS OF PREGNANCY AND DELIVERY AND ABNORMALITIES IN THE NEWBORN; Among all last deliveries, 18% of the women had pregnancy complications and 9% of the women had complications during delivery About 5% of the women reported abnormality in their most recent newborn. 8. REPRODUCTION EFFICIENCY; PERINATAL MORTALITY AND INFANT MORTALITY Based on data from the pregnancy history in this survey, reproduction efficiency was estimated. Out of the 11,154 pregnancies reported by all women surveyed, foetal loss was 21% (almost 16% were induced abortions) and infant deaths before reaching one year old were 3.1%. The reproduction efficiency was, therefore, reduced to 76%. In terms of perinatal and infant mortality rates, the former was 40.2 per 1,000 total births and the latter was 39.3 per 1,000 live births. Both rates described J shaped relationships with age of mothers and parity, and they were also correlated with birth interval and mother's education. In summary, this baseline survey data indicated a need for (1) improving contraceptive practices with more effective methods to prevent unwanted pregnancies and (2) providing better services for maternal and child care to protect wanted pregancies. In the Korean rural setting. the author believes that the latter is more important as the value of each child has increased as a result of the family planning campaign for the past two decades. This calls for more effective integration of Family Planning and MCH programmes to meet the needs of the family in each stage of the child bearing and rearing period with deploying more qualified personnel than the current government program personnel.

  • PDF

Analytical method study for cephalexin with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) applicable for residue studies in the whiteleg shrimp Litopenaeus vannamei (흰다리새우(Litopenaeus vannamei)에서 cephalexin의 잔류농도 연구를 위한 LC-MS/MS 분석법 연구)

  • Yang, Chan Yeong;Bae, Jun Sung;Lee, Chae Won;Jeong, Eun Ha;Lee, Ji-Hoon;Bak, Su-Jin;Choi, Sang-Hoon;Park, Kwan Ha
    • Journal of fish pathology
    • /
    • v.34 no.1
    • /
    • pp.71-80
    • /
    • 2021
  • Cephalexin, a semi-synthetic cephalosporin antibiotic, has long been used in fish aquaculture in various countries under legal authorization. The drug is thus widely available for use in other aquatic species except fishes like the crustacean whiteleg shrimp. This study aims to develop a sensitive method for laboratory residue studies to adopt in withdrawal period determinations. Through repeated trials from the existing methods developed for other food animal tissues, it was possible to achieve a sensitive high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method. The results showed that at a concentration of 0.1 mg/kg, the recovery rate was 81.79%, and C.V. value was 8.2%, which meet the recovery rate and C.V. recommended by Codex guideline. After satisfactory validation of analytical procedures, applicability to the shrimp tissue was confirmed in experimentally cephalexin-treated whiteleg shrimp. As a result, most muscle samples were detected below the limit of quantification (0.05 mg/kg) after day 3, and most hepatopancreas samples were detected below the limit of quantification after day 14. In particular, the limit of quantification 0.05 ppm with the presently developed method suggests sufficient sensitive over the current legal maximum residue limit of 0.2 mg/kg set for fishes.