• Title/Summary/Keyword: Body weight growth

Search Result 2,623, Processing Time 0.039 seconds

Administration of chromium picolinate and meloxicam alleviates regrouping stress in dairy heifers

  • Da Jin Sol Jung;Jaesung Lee;Do Hyun Kim;Seok-Hyeon Beak;Soo Jong Hong;In Hyuk Jeong;Seon Pil Yoo;Jin Oh Lee;In Gu Cho;Dilla Mareistia Fassah;Hyun Jin Kim;Mohammad Malekkhahi;Myunggi Baik
    • Animal Bioscience
    • /
    • v.37 no.8
    • /
    • pp.1495-1502
    • /
    • 2024
  • Objective: This research investigated the effect of administering chromium (Cr) and meloxicam (MEL) on growth performance, cortisol and blood metabolite, and behaviors in young, regrouped heifers. Methods: Fifty Holstein dairy heifers (body weight [BW] 198±32.7 kg and 6.5±0.82 months of age) were randomly assigned to non-regrouped group or four regrouped groups. Non-regrouped animals were held in the same pen throughout the entire experimental period (NL: non-regrouping and administration of lactose monohydrate [LM; placebo]). For regrouping groups, two or three heifers maintained in four different pens for 2 weeks were regrouped into a new pen and assigned to one of four groups: regrouping and LM administration (RL); regrouping and Cr administration (RC); regrouping and MEL administration (RM), and regrouping and Cr and MEL administration (RCM). LM (1 mg/kg BW), Cr (0.5 mg Cr picolinate/kg dry matter intake), and MEL (1 mg/kg BW) were orally administered immediately before regrouping. Blood was collected before regrouping (0 h) and at 3, 9, and 24 h and 7 and 14 d thereafter. Behaviors were recorded for 7 consecutive days after regrouping. Results: Average daily gain was lower (p<0.05) in RL than NL heifers, but was higher (p<0.05) in RM, RC, and RCM than RL heifers. RL heifers had higher (p<0.05) cortisol than NL heifers on d 1 after regrouping. The cortisol concentrations in RC, RM, and RCM groups were lower (p<0.05) than in RL treatment 1 d after regrouping. Displacement behavior was greater (p<0.05) in RL group than all other groups at 2, 3, and 6 d after regrouping. Conclusion: Regrouping caused temporal stress, reduced growth performance, and increased displacement behavior in heifers. Administering Cr and MEL recovered the retarded growth rate and reduced displacement behavior, thereby alleviating regrouping stress.

Studies for Antibiotic Free Chicken Production Using Water Extracts from Artemisia capillaris and Camellia sinensis (인진쑥 및 녹차 추출물을 이용한 무항생제 닭고기 생산 연구)

  • Kim, Dong-Wook;Kim, Ji-Hyuk;Kang, Geun-Ho;Kang, Hwan-Ku;Park, Sung-Bok;Park, Jae-Hong;Bang, Han-Tae;Kim, Min-Ji;Na, Jae-Cheon;Chae, Hyun-Suk;Choi, Hee-Chul;Suh, Ok-Suk;Kim, Sang-Ho;Kang, Chang-Won
    • Food Science of Animal Resources
    • /
    • v.30 no.6
    • /
    • pp.975-988
    • /
    • 2010
  • Two experiments were conducted to determine whether water extracts from Artemisia capillaries (A. capillaries) and Camellia sinensis (C. sinensis) could be used as alternatives to antibiotic growth promoters in broiler feed. The experiment 1 was verified their chemical composition, extracts yields, total phenolic compounds concentration, antioxidant activity, antimicrobial activity, and chicken splenocytes proliferation through in vitro test. The extract yields of A. capillaries and C. sinensis were 26.5 and 16.8%, respectively. Total phenolic compounds concentrations of them expressed as gallic acid equivalent were 15.28 and 26.74 mg/mL, respectively. Electron donating abilities of them expressed as $SC_{50}$ showing 50% DPPH radical scavenging were 0.30 and 0.06 mg, respectively. Bacterial inhibitory rates of them against Escherichia coli, Staphylococcus aureus, and Salmonella Typhimurium were ranged from 42.1 to 52.3% and from 21.6 to 33.7%, respectively. And, these extracts increased proliferation of chicken splenocytes. Especially, A. capillaris was more excellent than Echinacea and Concanavalin A known as T-cell stimulator. The experiment 2 was investigated their effects on growth performance, relative organ weight, cecal microflora, blood biochemical parameters, and splenic cytokines mRNA expression in broiler chicks. Four hundred eighty 1-day-old male broiler chicks (Ross 308) were divided in to 4 treatment groups with 4 replicates of 30 birds in each group: NC (control, no antibiotics), PC (avilamycin, 10 ppm; salinomycin, 60 ppm), AC (A. capillaries, 100 ppm), and CS (C. sinensis, 100 ppm); treatments were administered through water supplementation. Final body weight was significantly higher in all treated groups than in NC (p<0.05). Cecal Salmonella numbers were significantly or somewhat decreased in all treated groups than in NC (p<0.05). The relative weights and lengths of the small intestine were more significantly decreased in the PC and AC groups than in the other groups. Cecal Salmonella numbers were significantly or somewhat decreased in all treated groups than in the NC group (p<0.05). The contents of total cholesterol, aspatate aminotransferase, and alanine aminotransferase in blood serum were more significantly decreased in all treated groups than in NC (p<0.05). In conclusion, these results suggested the possibility that these extracts could serve as alternatives for antibiotic growth promoters.

Changes in Serum IGF-I and Spermatogenesis Analysed by Flow Cytometry in Growing Male Rabbit (성장 중인 수토끼에서 혈청 IGF-I 수준과 Flow Cytometry 측정에 의한 정자 형성의 변화)

  • Lee J. H.;Kim C. K.;Chang Y. M.;Ryu J. W.;Park M. Y.;Chung Y. C.;Pang M. G.
    • Reproductive and Developmental Biology
    • /
    • v.29 no.3
    • /
    • pp.163-168
    • /
    • 2005
  • The aim of this study was to investigate the changes in insulin-like growth factor-I (IGF-I) and growth hormone (GH) in serum, the quantitation of spermato-genesis and the comparable relationships among these measurements during pubertal period in New Zealand White male rabbits. To investigate the age-related testicular changes in DNA contents of spermatogenic cells, the fine-needle testicular biopsies from males aged 10 to 28 wks were evaluated by flow cytometry(FCM). Body weight increased significantly between the ages of 12 and 20 wks (P<0.05) and reached 3.4 kg at 28 wks of age. The highest serum IGF-I level (451.3ng/mL) was observed at 20wks of age (P<0.05) and thereafter remained stable at low levels. Serum GH level at 18 wks of age was 183.3 pg/mL which was significantly higher compared to the other ages (P<0.05), and the rising time in serum GH tend to be somewhat earlier than that of IGF-I. The relative percentage of It-cells in testicular cell compartments was $48.2\%$ at the age of 18 wks which significantly increased than those of 16-wk-old (P<0.05) and thereafter increased with the advance of age to $68\%$. The percentage of 2C-cells in testis was $26.8\%$ at 18 wks of age which was significantly lower than $54.3\%$ at 16 wks old (P<0.05). The percentage of 4C-cells was constantly maintained $2\~6\%$ except the $9.9\%$ at 18 wks of age. In conclusion, the results suggest that the puberty onset occurred at about the 18 wks of age and that the IGF-I and GH in serum during the pubertal period showed the age/growth-specific changes and these changes might be related to the spermatogenesis. The DNA FCM combined with fine-needle testicular biopsy could offer a very sensitive method to monitor the quantitative spermatogenic events related to the puberty onset.

Effects of Supplementation with Transgenic Bacillus subtilis Secreting Chitinase on Growth Performance, Nutrient Digestibility, Blood Characteristics, and Carcass Traits in Finishing Pigs (키틴분해효소를 분비하는 형질전환 Bacillus subtilis의 사료내 첨가가 비육돈의 성장, 영양소 소화율, 혈액성상 및 육질특성에 미치는 영향)

  • Kim, Hyo-Jin;Cho, Jin-Ho;Chen, Ying-Jie;Yoo, Jong-Sang;Wang, Yuan;Huang, Yan;Kim, In-Ho
    • Food Science of Animal Resources
    • /
    • v.28 no.2
    • /
    • pp.181-186
    • /
    • 2008
  • This study was conducted to investigate the effects of supplementation with transgenic Bacillus subtilis secreting chitinase on the growth performance, nutrient digestibility, blood characteristics and carcass traits in finishing pigs. A total of sixty-four pigs ($50.82{\pm}0.82kg$, average initial body weight) were assessed over a period of 84 days. Dietary treatments included: 1) CON (basal diet without antibiotics), 2) AD (basal diet + 0.1% Virginiamycin), 3) CD0.5 (basal diet + 0.5% transgenic B. subtilis), 4) CD1.0 (basal diet + 1.0% transgenic B. subtilis). Each dietary treatment had 4 replicates of 4 pigs per pen in a randomized complete block design. In terms of growth performance, the ADG (average daily gain) and gain/feed ratio were significantly increased with the CD1.0 diet compared to the AD diet during weeks 0-4 (p<0.05). During weeks 4-8, the ADG was significantly increased with the AD diet compared to the CON and CD0.5 diets (p<0.05). The ADFI was also significantly increased with the AD diet compared to the other diets (p<0.05). During weeks $8{\sim}12$, the ADFI was significantly increased with the CON diet compared to the other diets (p<0.05), and the gain/feed ratio was significantly increased with the CD0.5 and CD1.0 diets compared to the AD diet (p<0.05). Over the entire 84 day test period, the ADFI was significantly increased with the AD diet compared to the CD0.5 and CD1.0 diets (p<0.05). The gain/feed ratio was significantly increased with the CD0.5 and CD1.0 diets compared to the CON diet (p<0.05). In terms of meat color, the L value was significantly increased with the CD0.5 diet compared to the CON and AD diets (p<0.05), and the a value was significantly increased with the CON diet compared to the other diets (p<0.05). In terms of sensory evaluation, meat color was significantly improved with the CON, CD0.5 and CD1.0 diets compared to the AD diet (p<0.05). Marbling was significantly increased with the CON diet compared to the other diets (p<0.05). Firmness was significantly increased with the CD0.5 diet compared to the AD diet (p<0.05). In conclusion, supplementation with transformed B. subtilis secreting chitinase improved gain/feed ratios and influenced meat color. Thus, we suggest that transformed B. subtilis secreting chitinase can partially substitute for antibiotics.

Studies on the Effects of Caponization and Various Hormone Treatment on the Meat Production and Quality in Growing Chicken (닭에 있어서 거세(去勢) 및 Hormone 처리(處理)가 산육성(産肉性) 및 육질(肉質)에 미치는 영향(影響)에 관한 연구(硏究))

  • Ra, Kwang Yon
    • Korean Journal of Agricultural Science
    • /
    • v.2 no.1
    • /
    • pp.9-47
    • /
    • 1975
  • These experiments were caried out to study the effects of caponization and various hormone treatments upon meat production and improvement of meat quality of growing chicken. Sixtyseven days old 160 New Hampshire cockerels were treated and growth rate, carcass yield, change of weight of individual organs, meat composition and change of amino acid were measured and analysed. Otherwise change of testis and thyroid gland by hormone treatment were investigated histologically. The results obtained were as follows. 1. The effectst of caponization and hormone treatment upon meat production were; 1) Body weight of cockerels in D. E. S. group without caponization was increased. upon 96.86% than initial period and A. C. T. H. group was 104.22% but other groups and all carponization groups were lighter than those of control group. 2) Weekly body gain of D. E. S. group without caponization was best showing the significance (102.69 g) and the group with caponization were lower than those groups without caponization. 3) Carcass yield was best in Testo. group without caponization (831.2 g) and the group with caponization were lower than the group without caponization. 4) Carcass rate was highest in A. C. T. H. group with caponization and (67.22%) lowest in Testo. group without caponization (63.37%), but any significance was not recognized. 2. The effects of caponizatitn and hormone treatments upon the coposition of meat and amino acids were; 1) Any significance was not recognized between treated and untreated group about change of moisture, crude protein, crude ash and glycogen contents in meat. 2) Fat co tent in muscle in the all treated groups were higher than that of control group. 3) Extracts of group without caponization were higher than those of groups with caponization. 4) Lysin contents were highest in D. E. S. group with caponization (11. 12/ 16.0 g N) and generelly Testo. group was lower compared with D. E. S. group. 5) Histidine and Arginine contents were higher in the groups with caponization than without caponization. 6) Aspartic acid content were higher in D. E. S. group and A. C. T. H. group without depend on caponization. 7) Treonine content was higher in Testo. group without caponization and in the group with caponization and without hormone treatment compared with those of control group without caponization. 8) Serine content was decreased in the group with caponization and increased by D. E. S. and A. C. T. H treatment groups and glutamic acid was also decreased in Testo. group with out caponization. 9) Cystine content was decreased by Testo. treatment and was not appeared in Testo. group without caponization. 10) Valine content was lower in control group with caponization but significance was not recognized between other groups and control group without caponization. 11) Glycine, Alanine, Methionine. Isoleucine, Leucine, Thyrosine and Phenylalanine contents were not so difference between hormone treated groups and control group without caponization. 3. The effects of caponization and hormone treatment upon the change of organs were: 1) The weight of all organs were heaviest in D. E. S. group without caponization (18.5g) and lightest in A. C. T. H. group without caponization (155. 3g) but no significance was recognized between hormone treatment groups. 2) Heart weight was heaviest in D. E. S. group without caponization (7.46 g) and lightest in Testo. group without caponization (5.95 g). 3) Liver weight was heaviest in D. E. S. group without caponization(32.89g) and lightest in hormone untreated group with caponization(29.66g). Significance was not recognized. 4) Spleen weight was heaivest in Testo. group with caponization (3.22 g) and lightest in D. E. S. group without caponization(2.00g) in contrast with the other groups. High significance was recognized among the groups (P<0.01). 5) Cloacal thymus weight was lightest in D. E. S. group with or without caponization compared with control group without caponization. High significance was recognized among the groups. 6) Muscle fat content was not appeared in A. C. T. H. group with caponization, but it was highly increased in D. E. S. group with or without caponization. 7) Testis weight was lightest in D. E. S. group (0.38g) compared with control group (2.66g). Significance was recognized among the groups. 8) Large intestine, small intestine and cecum weight and length were heavier and longer in D. E. S. group without caponization and control group without caponization was lighter than those of hormone treated groups. 4. The effects of caponization and hormone treatment upon histological change of testis and thyroid gland: 1) The histological change of testis was significantly appeared in D. E. S. group that seminifirous tubles was slowly atrophied, the funtion of spernatogenesis was ceased, spermatocyte was changed as degeneration by pyknosis and karyorrhexis and interstitial cell was also atrophied, but in Testo. and A. C. T. H. group were similar as control group. 2) The histological change of thyroid gland in Testo. and A. C. T. H. groups without caponization were similar to that of control group without caponization, but in D. E. S. group without caponization, was changed squamously. Thyroid gland of the groups with caponization, epithelium of was atrophied and changed squamously as degeneration by pyknosis and karyorrhexis and the function of thyroid gland was slowly ceased in colloid and in hormone treated group with caponization.

  • PDF

Isolation and Structure Identification of Photosensitizer from Perilla frutescens Leaves Which Induces Apoptosis in U937 (들깻잎(Perilla frutescens)으로부터 U937 세포에 apoptosis를 유도하는 광과민성 물질의 분리 및 구조동정)

  • Ha, Jun Young;Kim, Mi Kyeong;Lee, Jun Young;Choi, Eun Bi;Hong, Chang Oh;Lee, Byong Won;Bae, Chang Hwan;Kim, Keun Ki
    • Journal of Life Science
    • /
    • v.25 no.1
    • /
    • pp.53-61
    • /
    • 2015
  • In this study, we tried to separate the photosensitizer that induces apoptosis of leukemia cells (U937) from perilla leaves. Perilla leaves (Perilla frutescens Britt var. japonica Hara) are a popular vegetable in Korea, being rich in vitamins (A and E), GABA, and minerals. Dried perilla leaves were extracted with methanol to separate the photosensitizer by various chromatographic techniques. The structure of the isolated compound (PL9443) was identified by 1D-NMR, 2D-NMR, and FAB-mass spectroscopy. Absorbance of the UV-Vis spectrum was highest at 410 nm and was confirmed by the 330, 410, and 668 nm. PL9443 compound was determined to be pheophorbide, an ethyl ester having a molecular weight of 620. It was identified as a derivative compound of pheophorbide structure when magnesium comes away from a porphyrin ring. Observation of morphological changes in U937 cells following cell death induced by treated PL9443 compound revealed representative phenomena of apoptosis only in light irradiation conditions (apoptotic body, vesicle formation). Results from examining the cytotoxicity of PL9443 substance against U937 cells showed that inhibition rates of the cell growth were 99.9% with the concentration of 0.32 nM PL9443. Also, the caspase-3/7 activity was 99% against U937 cells with the concentration of 0.08 nM of PL9443 substance. The result of the electrophoresis was that a DNA ladder was formed by the PL9443. The PL9443 compound is a promising lead compound as a photosensitizer for photodynamic therapy of cancer.

Nutrition of Calcium and Phosphorus in Poultry Diets (닭에 대한 칼슘과 인의 영양)

  • 한인규;오상집
    • Korean Journal of Poultry Science
    • /
    • v.8 no.2
    • /
    • pp.55-68
    • /
    • 1981
  • Calcium and phosphorus are not only indispensable for the bone formation and body fluids equilibrium but also are major components of egg shell. It is nutritionally important, therefore, to investigate the metabolism of calcium and phosphorus and to search for optimum requirement of calcium and phosphorus and the availability of various sources of calcium an4 phosphorus by poultry. An attempt was made to review the nutrition of calcium and phosphorus in poultry diets. 1, Calcium and phosphorus have great interrelationship with vitamin D in their metabolisms. 2. Most of the plant-origin phosphorus are existing in phytic form and it leads to low availability when used in poultry rations, although calcium and phosphorus present in animal-origin or mineral supplements are highly available in general. 3. Calcium and phosphorus requirement from existing information indicated that 1.0% calcium and 0.7% phosphorus for broiler and egg-type chicks, and 3.5% calcium and 0.4% phosphorus for laying hen. 4. It has been recommended that calcium and phosphorus level should be increased when the feed intake was decreased or when the egg Production rate was higher or when the hens are old. 5. Mono-, ci-, tri-, calcium phosphate, calcium carbonate, bone meal, limestone and oyster shell u the most readily available among various sources of calcium phosphorus supplements. Soft rock phosphate, deflourinated phosphate and gypsum are somewhat inferior to the previous ones in bioavailability. 6. The effect of particle size of calcium supplements on egg shell quality and egg production rate is not yet clearly defined but recent works showed that oyster shell is more available when it was coarse and limestone is more available when it was fine in panicle. size. 7. Present data indicated that mixed feeding of oyster shell and limestone is superior to the single feeding of each on laying performance. 8. Significant interaction between phosphorus and sodium was observed, that is, excessive sodium decreased egg production in layer and body weight growth in broiler in the low phosphorus diets but increased them in the high phosphorus diets.

  • PDF

Effect of Dietary Supplementation of Acanthopanax senticosus and Eucommiaceae on the Expression of Lipogenic, Myogenic and Antioxidant Enzyme Genes in Broiler Chickens (육계에서 가시오갈피와 두충의 첨가 급여가 항산화 효소, 지방 및 근육 관련 유전자 발현에 미치는 영향)

  • Kang, H.K.;Beloor, J.;Sohn, S.H.;Jang, I.S.;Moon, Y.S.
    • Korean Journal of Poultry Science
    • /
    • v.36 no.1
    • /
    • pp.39-45
    • /
    • 2009
  • This study was carried out to investigate the effect of dietary supplementation of Acanthopanax (A) senticosus and Eucommiaceae on the expression of lipogenic, myogenic and oxidative stress genes in broiler chickens. Birds were subjected (assigned) to one of the following 5 dietary treatments: control (CON), A. senticosus 0.5% (T1), 1.0% (T2), Eucommiaceae 0.5% (T3) and 1% (T4). Each treatment was replicated 8 times with 4 birds per replication, housed in 4 birds per cage. Birds were arranged according to randomized block design. Feeding trial was conducted from day 4 to 35th day of age. Liver and muscle tissues were collected for analysis. Broilers subjected to 1% A. senticosus had higher feed conversion ratio than the other treated birds whereas no significant differences were found in body weight, weight gain and feed intake. The gene expression levels of fatty acid synthase were not different among the treatments while the transcription factor $PPAR{\gamma}$ was highly expressed in Eucommiaceae but not in control and A. senticosus. The gene expression levels of myogenin were high in both A. senticosus and Eucommiaceae compared to control group. MyoD also showed high expression in treated groups furthermore, Eucommiaceae stimulated the expression of MyoD more than that of A. senticosus. The antioxidant gene expressions (SOD, CAT, SOD, GPX) generally were not much different among the treatments, however, SOD and GPX were stimulated in broilers consumed 1% Eucommiaceae diet. The result of this experiment showed that dietary supplementation of A. senticosus and Eucommiaceae in broiler may improve the antioxidant defence system through SOD and GPX without affect of growth performance in broilers.

Effects of Dietary Xanthophylls and See Weed By-Products on Growth Performance, Color and Antioxidant Properties in Broiler Chicks (Xanthophylls과 해조 부산물 첨가 급여가 육계의 사양성적, 육색 및 항산화 특성에 미치는 영향)

  • 김창혁;이성기;이규호
    • Food Science of Animal Resources
    • /
    • v.24 no.2
    • /
    • pp.128-134
    • /
    • 2004
  • This experiment was conducted to investigate the effects of dietary pigment sources on the performance, color and antioxidant properties in broiler chick. Experimental diet was formulated to have isocalories and isonitrogen during the experiment period. Total xanthophylls content in the experimental diet was formulated to have 30ppm. Experimental trials were done for five weeks with six treatment groups; T1 (Control), T2 (Olo Glo, natural yellow pigment), T3 (Kern Glo, natural red pigment), T4 (canthaxanthin, synthetic red pigment), T5 (asthaxanthine, natural red pigment), and T6 (seaweed by-products). Body weight gain and feed intake were significantly lower (p<0.05) in T6 group than in other treatments. Mortality was lower in T2, T3 and T4 than in control, but higher (p<0.05) in T5 and T6. The sources of pigments did not have any effects on the dressed carcass and abdominal fat pad (p>0.05). The gizzard weight was significantly lower in T6 (p<0.05) than in others. Pigmentation of leg skin was significantly lower (p<0.05) in control and T6. Effects of dietary pigments was greater with red pigments than with yellow pigments, and those were also greater with natural pigments than with synthetic ones. The peroxide value (POV), thiobarbituric acid reactive substances (TBARS) and pH values of chicken meat were increased (p<0.05) in all treatments at 12 day storage, and was higher (p<0.05) in pigments supplementation group. No differences of CIE L$\^$*/(lightness) and b$\^$*/(yellowness) were not found by storage days and xanthophylls sources. The a$\^$*/(redness) after 12 day storage was significantly (p<0.05) decreased in all treatments, but those of T4 and T5 were higher than those of others. These results showed that feeding of xanthophylls sources to chick could improve color intensity and inhibit lipid oxidation of leg meat.

Factors Related to Poor School Performance of Elementary School Children (국민학교아동의 학습부진에 관련된 요인)

  • Park, Jung-Han;Kim, Gui-Yeon;Her, Kyu-Sook;Lee, Ju-Young;Kim, Doo-Hie
    • Journal of Preventive Medicine and Public Health
    • /
    • v.26 no.4 s.44
    • /
    • pp.628-649
    • /
    • 1993
  • This study was conducted to investigate the factors related to the poor school performance of the elementary school children. Two schools in Taegu, one in the affluent area and the other in the poor area, were selected and a total of 175 children whose school performance was within low 10 percentile (poor performers) and 97 children whose school performance were within high 5 percentile (good performers) in each class of 2nd, 4th and 6th grades were tested for the physical health, behavioral problem and family background. Each child had gone through a battery of tests including visual and hearing acuity, anthropometry (body weight, height, head circumference), intelligence (Kodae Stanford-Binet test), test anxiety (TAI-K), neurologic examination by a developmental pediatrician and heavy metal content (Pb, Cd, Zn) in hair by atomic absorption spectrophotometry. A questionnaire was administered to the mothers for prenatal and prenatal courses of the child, family environment, child's developmental history, and child's behavioral and learning problems. Another questionnaire was administered to the teachers of the children for the child's family background, arithmatic & language abilities and behavioral problem. The poor school performance had a significant correlation with male gender, high birth order, broken home, low educational and occupational levels of parents, visual problem, high test anxiety score, attention deficit hyperactivity disorder (ADHD), poor physical growth (weight, height, head circumference) and low I.Q. score. The factors that had a significant correlation with the poor school performance in multiple logistic regression analysis were child's birth order (odds ratio=2.06), male gender(odds ratio=5.91), broken home(odds ratio=9.29), test anxiety score(odds ratio=1.07), ADHD (odds ratio=9.67), I.Q. score (odds ratio=0.85) and height less than Korean standard mean-1S.D.(odds ratio=11.12). The heavy metal contents in hair did not show any significant correlation with poor school performance. However the lead and cadmium contents were high in males than in females. The lead content was negatively correlated with child's grade(P<0.05) and zinc was positively correlated with grade (P<0.05). among the factors that showed a significant correlation with the poor school performance, high birth order, short stature and ADHD may be modified by a good family planning, good feeding practice for infant and child, and early detection and treatment of ADHD. Also, teacher and parents should restrain themselves from inducing excessive test anxiety by forcing the child to study and over-expecting beyond the child's intellectual capability.

  • PDF