• Title/Summary/Keyword: M.T.T.F.

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Ecophysiological Studies on the Water Relations of Economic Tree Species - Temporal Changes of Stomatal Responses to Soil Moisture Regimes and Exogenous Abscisic Acid in Oaks and Ash - (주요 경제 수종의 수분 특성에 관한 생리생태학적 연구 - 토양수분 조건 및 ABA 처리에 따른 참나무류와 물푸레나무 기공의 시계열적인 변화 반응 -)

  • Kwon, Ki Won;Lee, Jeoung Ho
    • Journal of Korean Society of Forest Science
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    • v.83 no.3
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    • pp.410-423
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    • 1994
  • Seasonal and diurnal changes of stomatal diffusive resistance(S.D.R.) and transpiration rate(T.R.) were investigated for determining the ecophysiological water relations of economic tree species subjected to chronic water stress or exogenous abscisic acid treatment. Four species of oaks including Quercus serrata, Q. mongolica. Q. acutissima, and Q. variabilis were used as the experimental materials and also Fraxinus rhynchophylla was studied together with oaks. Stomatal diffusive resistances were repeatedly measured on the containerized 1-0 year seedlings subjected to two kinds of soil moisture regime (wet and dry) in June, August, and September by LI-1600 Steady State Porometer of LI-Cor, Inc.. Exogenous abscisic acid (ABA) solutions of 0.5 mM and 0.05 mM in July and August, respectively, were absorbed into shoots cut from the containerized seedlings for determining their effects on stomatal behavior and transpiration. Most of measurements in stomatal diffusive resistance maintained about 5 s/cm in the morning after sunrise despite of different treatments. But the values fluctuated frequently to high level above 20 s/cm through the afternoon until sunset in the seedlings subjected to dry soil moisture regime. Despite of various treatments and environmental conditions, stomatal diffusive resistances of Q. variabilis were more stable than those of Q. serrata or Q. acutissima. Their values of F. rhynchophylla changed more irregularly in comparison with those of oak species. Exogenous abscisic acid absorbed into shoots cut from seedlings increased stomatal diffusive resistance obviously in most of the species studied. The stomatal responses to abscisic acid treatment were more sensitive in July especially in Q. serrata than in Q. variabilis and Q. acutissima. But the effects of ABA treatment were presented more remarkably in Q. acutissima in August. The responses to abscisic acid were not certain in F. rhynchophylla because of their various fluctuation patterns.

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A Simple Isolating Method of Preantral Follicles from Mouse Ovaries (생쥐 난소에서 Preantral Follice의 단순 분리법)

  • Kim, Ju-Hwan;Park, Kee-Sang;Song, Hai-Bum;Chun, Sang-Sik
    • Clinical and Experimental Reproductive Medicine
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    • v.27 no.3
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    • pp.235-243
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    • 2000
  • Objective: Our present studies were conducted to examine more effective isolating method of preantral follicles from mouse ovaries. Methods: ICR mice (3-6 weeks old) were sacrificed through cervical dislocation and their ovaries were removed and put into watch glasses containing Hams F-10 supplemented with 10% fetal bovine serum (FBS). Preantral follicles were isolated by three different methods; 1) enzymatical method and 2) mincing method, and 3) scraping method. Enzymatical method was carried out as following. Ovaries were bisected with a pair of fine 30G needles. Bisected ovaries were incubated at $37^{\circ}C$ and 5% $CO_2$ incubator in 2-well dish containing Hams F-10 supplemented with collagenase 600 lU/ml and DNAse 20 lU/ml. After 20 min., follicles were isolated by repeated pipetting. Isolated preantral follicles were collected, and the remnant of tissues was placed in incubator and previous procedure was repeated. Mincing method was carried out with a pair of fine 30G needles attached to 1 ml syringes and minced ovary. Scraping method was carried out with a pair of fine 30G needles and scratched to surface of ovary. The differences between isolating methods were analyzed using Student's t-test and Chi-square. Results were considered statistically significant when ${\rho}$ value was less than 0.05. Results: In handling time, mincing or scraping method ($28{\pm}3.42$ min or $16{\pm}1.58$ min) were significantly (p<0.00001) shorter than enzymatical method ($72{\pm}1.69$ min), and scraping method was significantly (p<0.01) shorter than mincing method. Total number of isolated follicles was significantly (p<0.0001) higher in enzymatical method ($49.8{\pm}3.91$) than in mincing or scraping method ($25.3{\pm}2.33$ or $20.5{\pm}1.75$). Isolated follicles in ${\leq}$90${\mu}m$ were significantly (p<0.005) higher in enzymatical method ($15{\pm}1.71$) than in mincing or scraping method ($7.8{\pm}0.98$ or $8.1{\pm}1.31$). In 91~130 ${\mu}m$, isolated follicles were significantly (p<0.0005) higher in enzymatical method ($33{\pm}3.27$) than in mincing or scraping method ($16.3{\pm}1.82$ or $10.7{\pm}1.38$). In ${\geq}$ 131 ${\mu}m$, isolated follicles were not significantly differences between all groups. In equal sizes, the rate of isolated follicles in ${\leq}$ 90 ${\mu}m$ was highest in scraping method (39.6% vs. enzymatical method: 30.1%, p<0.05; mincing method: 30.9%, p=0.11719, NS). Rate of follicles in $91{\sim}130$ ${\mu}m$ was significantly (p<0.05) lower in scraping method (52.7%) than in enzymatical or mincing method (66.3% or 64.5%). Rate of follicles in ${\geq}$131 ${\mu}m$ was highest in scraping method (8.3% vs. enzymatical or scraping method: 3.6%, p<0.05 or 4.6%, p=0.19053, NS). Conclusions: This study suggests that scraping method is simple and useful for isolation of preantral follicles, because this method reduced handling time and recovered enough follicles. The recovered rate of isolated follicles in diameter of 91 ~ 130 ${\mu}m$ was highest in all methods.

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Short-Term Storage and Cryopreservation of Abalone (Haliotis discus hannai) Sperm

  • Kang, K.H.;Kho, K.H.;Chen, Z.T.;Zhang, Z.F.;Chang, Y.J.
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2003.10a
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    • pp.74-74
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    • 2003
  • In present study, attempts were made to preserve abalone (Haliotis discus hannai) sperm in liquid form at low temperature, to evaluate the effect of various diluents in short-term storage on sperm, and cryopreservation procedures were optimized for the cryoprotectants as well as freezing rates, in terms of the motility and survival rate, and the ultrastructural changes of sperm after short-term storage and cryopreservation were observed. The abalone sperm reached maximum motility until about 4min after activation. The motility was constant for about 16min, after which it dropped gradually, and about 50min later all motility ceased. Threshold activation of sperm was found in 40% artificial seawater (ASW), and motility increased as the concentration of ASW increased. In Hanks balanced salt solution without calcium (Ca-Free HBSS, 300 and 400 mOsmol/kg) and 10%, 20%, and 30% ASW the sperm was immotile, and motility once again restored incompletely only in HBSS of 300 and 400 mOsmol/kg, 20% and 30% ASW after 100% ASW was added. Sperm motility was extended following 20 days of cold storage only in 70% and 100% ASW. A high motility index of 3.5-4.5 was observed for the first 8 days in 70% and 80% ASW. In other diluents sperm motility was constant less than 10 days, and the motility index was obviously lower than that of sperm in 70% and 100% ASW. After 20 days of cold storage survival rates of 10.2%-20.7% were obtained in ASW and 300 mOsmol/kg HBSS, and that in 400 HBSS (65.3%) was significantly higher than others. The constant period of sperm motility stored in 70% ASW was longer obviously than that in 100% ASW after 6 days of storage, and the time to maximum motility of sperm stored in 70% increased gradually, while the difference in which of sperm in 100% ASW was not significant. The sperm plunged into liquid nitrogen all died except that sperm using 15% glycerol as cryoprotectant restored 10.4% of motility. The highest motility index (3.4) was obtained with 5% glycerol and freezing procedure: $50^{\circ}C$/min from $20^{\circ}C$ to $-80^{\circ}C$.

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Dry Matter Digestion Kinetics of Two Varieties of Barley Grain Sown with Different Seeding and Nitrogen Fertilization Rates in Four Different Sites Across Canada

  • Cleary, L.J.;Van Herk, F.;Gibb, D.J.;McAllister, T.A.;Chaves, A.V.
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.7
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    • pp.965-973
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    • 2011
  • Our objective was to determine the differences in the rate and extent of dry matter digestion between barley subjected to differing agronomic variables. Two malting barley varieties, Copeland and Metcalfe were seeded at rates of 200 and 400 plants/$m^2$. Each of these varieties received nitrogen fertilizer at rates of 0, 30, 60 and 120 kg/ha, resulting in a total of 20 different barley grain samples. Samples were ground through a 6mm screen and approximately 3 g of each weighed into 50 ${\mu}m$ Dacron bags and sealed. The bags were incubated in three ruminally cannulated Holstein cattle for periods of 0, 3, 6 and 24 h. Using the data obtained from these incubations, rates of digestion were able to be predicted. The soluble fraction ranged from 0.229-0.327, the slowly degradable fraction ranged from 0.461-0.656, and the undegradable fraction ranged from 0.038-0.299. The rates of digestion ranged from 0.127-0.165 $h^{-1}$ and the effective degradability ranged from 0.527-0.757. At the Canora location, the Copeland samples which received 120 kg/ha of nitrogen fertilizer had a significantly lower (p = 0.013) soluble fraction than the rest of the samples at that location. A significant interaction (p = 0.009) was seen between the seeding rate and nitrogen fertilizer application with samples from the Canora location, as well as significant differences (p = 0.029) between nitrogen application rates in samples from the Indian head location. The rate of digestion of samples from the Indian head location differed (p = 0.020) between the two seeding rates, with samples seeded at 200 seed/$m^2$ having a slightly higher rate of degradation. Differences in the effective degradability were seen between the different nitrogen application rates with samples from both the Canora and Indian head locations, as well as an (p = 0.004) interaction between the seeding rate and nitrogen fertilizer application rate. Although there was not a clear correlation between the different variables, both nitrogen application and seeding rate did have a significant effect on the rates and extent of digestion across each of the four locations.

The Analysis on the Academic Information Seeking Behavior of College Professors: A Social Scientist Group in the K-University (대학교수들의 학술정보원 이용행태분석: K대학의 사회과학교수집단을 중심으로)

  • 박준식;박일종;신상헌
    • Journal of the Korean Society for information Management
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    • v.17 no.3
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    • pp.21-43
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    • 2000
  • Not only the infomatmn seeking bellavmr or acadenuc sources by social scientists was analyzed bnt its eiieclive usmg method was also presented in this paper. For thc purpose, the questionnaires were prepared md admmislered lo social sacnilsin who are the profcsso~s oi a large unlverslty m Taegu, Korea. and the survey for tiler academic environment and its sateiaclion, characterislics, inforn~ahon seeking behavior of academic sources, etc. was conducted. Also, iheir research mlercsts and period, informauon s e e h g behav~or and its dfficulties, reineval melhods, and uslng rrequcncies of current issues elc. were analyzed in lliis paper. The major hdings ol the quanm.live pa on the development 01 academic sources for soaal sciencc study and t11e11 uses for education md study m !hi7 study are: (1) Socid sclenhsts preferred acquiring matenal ihrougli internet. CD-ROM, and PC, etc, lo the traditional methods; (2) They spend approxinmtciy 41 days for collecihg matend they wanl. and each of them has petty various period la collect n~atenal and acquiring methods. (standard deviation : about 35 days); (3) The cilalion kequencies of fore~gu material was hi&r than domeslic one; (4) They, social sc~entists, have a pretty hard time to access and use the theses, journal, magazinc. mmol~ches and m s r o f i , CD-ROM malerid etc. technicdly; (5) The group that has morc sat~sIaclion to thesa aud more fiequenl participant ol seminar seek [or more recen issues of a journal lhrough ihc research modcl of melag. (6) The group thal has higher positioned and 1on.a tenure o: office can access lo shorter time at period lhau the one that bas lhe lowcr and the shortcr group. Also, tutule research topic and recommcndations [or a ~ocial saentlst are proposed and suggested when using a social science material

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Gas Exchanges and Dehydration in Different Intensities of Conditioning in Tifton 85 Bermudagrass: Nutritional Value during Hay Storage

  • Pasqualotto, M.;Neres, M.A.;Guimaraes, V.F.;Klein, J.;Inagaki, A.M.;Ducati, C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.6
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    • pp.807-815
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    • 2015
  • The present study aimed at evaluating the intensity of Tifton 85 conditioning using a mower conditioner with free-swinging flail fingers and storage times on dehydration curve, fungi presence, nutritional value and in vitro digestibility of Tifton 85 bermudagrass hay dry matter (DM). The dehydration curve was determined in the whole plant for ten times until the baling. The zero time corresponded to the plant before cutting, which occurred at 11:00 and the other collections were carried out at 8:00, 10:00, 14:00, and 16:00. The experimental design was randomised blocks with two intensities of conditioning (high and low) and ten sampling times, with five replications. The high and low intensities related to adjusting the deflector plate of the free iron fingers (8 and 18 cm). In order to determine gas exchanges during Tifton 85 bermudagrass dehydration, there were evaluations of mature leaves, which were placed in the upper middle third of each branch before the cutting, at every hour for 4 hours. A portable gas analyser was used by an infrared IRGA (6400xt). The analysed variables were photosynthesis (A), stomatal conductance (gs), internal $CO_2$ concentration (Ci), transpiration (T), water use efficiency (WUE), and intrinsic water use efficiency (WUEi). In the second part of this study, the nutritional value of Tifton 85 hay was evaluated, so randomised blocks were designed in a split plot through time, with two treatments placed in the following plots: high and low intensity of cutting and five different time points as subplots: cutting (additional treatment), baling and after 30, 60, and 90 days of storage. Subsequently, fungi that were in green plants as well as hay were determined and samples were collected from the grass at the cutting period, during baling, and after 30, 60, and 90 days of storage. It was observed that Tifton 85 bermudagrass dehydration occurred within 49 hours, so this was considered the best time for drying hay. Gas exchanges were more intense before cutting, although after cutting they decreased until ceasing within 4 hours. The lowest values of acid detergent insoluble nitrogen were obtained with low conditioning intensity after 30 days of storage, 64.8 g/kg DM. The in vitro dry matter of Tifton 85 bermudagrass did not differ among the storage times or the conditioning intensities. There was no fungi present in the samples collected during the storage period up to 90 days after dehydration, with less than 30 colony forming units found on plate counting. The use of mower conditioners in different intensities of injury did not speed up the dehydration time of Tifton 85.

Anti-oxidative Activities for the Flavonoids of the Syzygium aqueum Burm.f. Alston Branches from Jeju Island (제주 자생 물사과 가지 유래 Flavonoid 화합물의 항산화 활성)

  • Yeom, Hyun Sook;Lee, Nam Ho;Hyun, Ju Mi
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.2
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    • pp.151-159
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    • 2018
  • In this study, we investigated the anti-oxidative activities and cell protective effects of the constituents isolated from S. aqueum branches. DPPH and $ABTS^+$ radical scavenging activities were screened for the ethanol extract and solvent fractions, ethyl acetate (EtOAc) and butanol (BuOH) fractions showed potent activities. When HaCaT cells were treated with $H_2O_2$, the ethanol extract and EtOAc fractions ($20{\mu}g/mL$) protected the cells against oxidative damage. Two constituents were isolated from the EtOAc fraction of S. aqueum branches; pinocembrin (1), desmethoxymatteucinol (2). The chemical structures of the isolated compounds were elucidated based on the spectroscopic data including $^1H$ and $^{13}C$ NMR spectra, as well as comparison of the data to the literature values. Anti-oxidative activities and cell protective effects were studied for the isolated compounds. For the anti-oxidative activities, all of the compounds 1 and 2 showed DPPH and $ABTS^+$ radical scavenging activities. Also, from the cell protective effect test, the compounds 1 and 2 protected the cell against oxidative stress by $H_2O_2$. Based on these results, S. aqueum branches extract could be potentially applicable as anti-oxidant ingredients in cosmetic industries.

Diagnosis and Treatment of Hirschsprung's Disease in Korea - Current Status of 1992 - -A Survey f or Surgeon's Preference among the Members of the Korean Association of Pediatric Surgeons in 1992- (Hirschsprung's Disease의 진단과 치료 : 1992년도 현황 -대한소아외과학회 회원대상 선호도 설문조사-)

  • Yeo, S.Y.;Kim, S.Y.;Kim, W.K.;Kim, I.K.;Kim, J.E.;Park, K.W.;Park, W.H.;Park, J.S.;Song, Y.T.;Oh, S.M.;Lee, D.S.;M.D., Lee;Lee, S.C.;Chang, S.I.;Chung, S.Y.;Chung, E.S.;Jung, P.M.;Joo, J.S.;Choi, K.J.;Choi, S.O.;Choi, S.H.;Huh, Y.S.;Hwang, E.H.
    • Advances in pediatric surgery
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    • v.2 no.1
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    • pp.33-41
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    • 1996
  • This report present the result of the national survey of pediatric surgeons' preferences on diagnosis and treatment of Hirschsprung's disease(HD) carried out in 1993. The questionnaires were sent to twenty-seven members of the Korean Association of Pediatric Surgeons (KAPS) working in twenty-four institutions. The questionnaires were designed to determine the individual surgeon's preference for the methods of diagnosis and treatment of the disease. Twenty-three pediatric surgeons from twenty institutions returned completed forms. The total number of patients diagnosed with HD in 1992 was 190 in this group. The estimated incidence of HD was 1/3,900. The most important symptom was delayed meconium passing and the most preferred diagnostic procedure was barium study. Anorectal manometric examination was carried out by 13 pediatric surgeons and 19 confirmed the diagnosis before operation by rectal biopsy, 12 with full-thickness biopsy and 7 with suction. Frozen section biopsy during operation was done by 22 surgeons. Eight surgeons did one stage operation if the age of the patient is suitable. Definitive operation was usually done at the age of 6 to 11 months. The most preferred operation was Duhamel procedure done by 19. Enterocolitis was the most serious complication of HD. Most of patients had normal continence within 6 to 12 months after operation. The follow-up period was less than 6 years in 16 surgeons. The results were presented at the 9th annual meeting of KAPS in June of 1993. This is the first national survey of HD and it can provide guidelines of diagnosis and treatment of Hirschprung's disease even though it is not a detailed study of patient data.

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Expression of Antisense Mouse Obese Gene in Transgenic Mice (형질전환 생쥐에서 Antisense 비만유전자의 발현)

  • Kwon, B.S.;Hong, K.H.;Jahng, J.W.;Lee, H.T.;Chung, K.S.
    • Korean Journal of Animal Reproduction
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    • v.24 no.4
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    • pp.419-428
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    • 2000
  • Leptin, the product of obese (ob) gene, is an adipocyte-derived satiety factor that plays a major role in the regulation of food intake, energy homeostasis, body weight, reproductive physiology and neuropeptide secretion. The present study was designed to generate transgenic mice expressing antisense mouse ob (mob) gene. Total RNA was extracted from the adipose tissues of mouse, then reverse transcription was performed. The 303 and 635 bp fragments of anti I and II cDNAs were amplified from mob cDNAs by PCR. The two mob cDNAs were reversely ligated into between adipose tissue specific aP2 promote and SV40 poly(A) site. Transgenic mice carrying two different kinds of antisense mob transgenes were generated by DNA microinjection into pronucleus. Total 14 transgenic mice were born, and the 4 and 5 founder lines of the transgenic mice with anti I and II transgenes were respectively established. Antisense mRNA expression was detected in transgenic F$_1$ mice by RT-PCR analysis. This result suggests that the transgenic mice expressing antisense mob mRNA may be useful as an animal disease model to be obesity caused by decreased amount of leptin secretion.

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The Additivity of True or Apparent Phosphorus Digestibility Values in Some Feed Ingredients for Growing Pigs

  • Fang, R.J.;Li, T.J.;Yin, F.G.;Yin, Y.L.;Kong, X.F.;Wang, K.N.;Yuan, Z.;Wu, G.Y.;He, J.H.;Deng, Z.Y.;Fan, M.Z.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.7
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    • pp.1092-1099
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    • 2007
  • Two experiments were conducted to determine the additivity of apparent or true digestibility of phosphorus (P) in soybean meal (SBM), peas, faba beans, corn, oats, broken rice meal, rough rice meal, buckwheat, and sorghum for growing pigs. Chromic oxide (0.3%) was used as a digestion marker in both experiments. Each experiment lasted for 12 d, which consisted of a 7-d dietary adaptation period followed by a 5-d fecal collection period. Experiment 1 involved 6 diets: the SBM-based control diet; 4 diets with corn, oats, rough rice meal and broken rice meal substituted for SBM; and an additional diet with a representative mixture of the 5 ingredients. In Experiment 2, 6 diets were prepared similarly, except that the tested ingredients besides SBM were faba beans, peas, buckwheat, and sorghum. In each experiment, six barrows with an initial average individual BW of 20.5 kg were fed one of the six diets according to a $6{\times}6$ Latin square design. The apparent and true P digestibility values for the nine tested ingredients were determined by the substitution method. There were no differences (p>0.05) between the determined and the predicted true P digestibility values for the mixture of ingredients in Experiments 1 and 2. However, the determined and the predicted apparent P digestibility values for the mixture of ingredients differed (p = 0.059) in Experiment 1, but not in Experiment 2. These results indicate that true P digestibility values are additive in ingredients containing low levels of phytate phosphorus and anti-nutritional factors, whereas the apparent P digestibility values are not always additive in single feed ingredients for growing pigs.