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1.
Growing pigs, varying in body weight between 25 and 110 kg, showed differences in fat content between adipose tissues from different body sites. In all adipose tissues fat content increased during growth; the increase in fat content was, as shown for backfat, affected by the level of daily energy intake. It is concluded that the dry matter (DM) or fat content in a single sample of adipose tissue cannot be used as an accurate parameter for fatness of carcasses at a normal slaughter weight.  相似文献   

2.
Little is known about the function of individual backfat layers in swine. Our objective in this study was to evaluate differential growth of each backfat layer in pigs fed different amounts of the same diet. Relationships of growth of backfat layers to deposition of carcass protein and ether extract were also studied. Feed intake levels were ad libitum, 92.5% of ad libitum, and 85% of ad libitum for 36 barrows averaging 95 d of age and 37.8 kg of weight at the start of the study. Chemical composition of the carcass soft tissue was determined at the end of the 84-d study. Daily gain tended to decrease (P less than .10) and conversion of feed to gain improved (P less than .15) as feed intake decreased. The daily depositions (g/d) of protein and ether extract were 62.9 and 205 for the ad libitum group, 61.1 and 176 for the 92.5% intake group, and 59.3 and 153 for the 85% intake group, respectively. The compositional effect of limiting feed intake for 84 d was to produce less carcass soft tissue of greater lean content. Overall backfat depths were 31.5, 29.6, and 27.8 mm for the ad libitum, 92.5, and 85% intake groups, respectively. The outer backfat layer differed among groups; the 92.5 and 85% groups were thinner than the ad libitum group. Relative to the ad libitum group, the change in depth of the middle backfat layer was 86 and 75% for the 92.5 and 85% intake groups (P less than .01). The inner backfat layer was not affected significantly by level of feed intake.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Sixty-one finishing pigs (53.4 kg) were fed a control diet (containing soybean meal) or diets containing 20% intact canola (IC) or 20% ground canola (GC) for 8 wk. Diets were not isocaloric. Daily gain and feed efficiency were not affected by dietary treatment, but pigs fed GC ate less than pigs fed either IC or the control diet. Carcass measurements, obtained on 43 of the pigs, were not affected by diet. For 27 pigs, fatty acid composition of perirenal adipose tissue (PRF), subcutaneous adipose tissue (SCF), and longissimus muscle (LDM) was analyzed. Nine pigs (three per treatment) were randomly selected for fatty acid composition analysis of intramuscular adipose tissue (IMF) and for cholesterol analysis of several tissues. Pigs fed canola had greater (P less than .05) proportions of mono- and polyunsaturated fatty acids and less (P less than .05) saturated fatty acids in PRF and SCF. The differences were more pronounced for PRF than for SCF. In the LDM, pigs fed canola tended to have elevated levels of unsaturated fatty acids at the expense of the saturated fatty acids, but this effect was significant for linolenic acid only. The fatty acid composition of IMF was not affected by diet (P greater than .05). Diet did not alter the cholesterol content of the tissues, but cholesterol in IMF was higher (P less than .05) than in PRF, SCF, and LDM. In conclusion, 20% IC or GC did not alter growth performance or carcass characteristics of pigs. Feeding of canola increased the degree of unsaturation of PRF and SCF, but it had less effect on IMF and LDM.  相似文献   

4.
5.
J.P. Jiang  J. Zhou  J. Chen  X.H. Wei  T.S. Lu  H. Chi  R.Q. Zhao   《Livestock Science》2007,107(2-3):235-243
Chicken egg yolk antibody against pig adipose tissue plasma membranes (AIgY) was raised and used in the present experiment to evaluate the effect of dietary AIgY supplementation on pig growth and carcass composition. 160 crossbred (Duroc–Jersey × Landrace·Meishan) pigs, with initial live body weight of 27.5 ± 2.4 kg, were treated with AIgY or non-immunized control egg yolk powder (NIgY) at the inclusion level of 75 mg/kg diet. Following a 104-day trial, the pigs were slaughtered for analyzing the carcass and meat quality traits. The perirenal, mesenteric and subcutaneous fat depots were weighed and the diameter of adipocytes from different fat depots was measured with histological methods. Serum concentrations of insulin and leptin as well as the activities of malic enzyme (ME) and lipoprotein lipase (LPL) in adipose tissue were measured. Dietary supplementation of AIgY enhanced average daily gain and feed efficiency by 13.03% (P < 0.01) and 7.49%, respectively, with no influence on feed consumption. AIgY increased the lean mass by 10.3% (P < 0.01) without affecting the dressing percentage. Backfat thickness at 6th–7th rib and the weights of perirenal, mesenteric and subcutaneous fat depots were reduced by 24.14% (P < 0.01), 27.27% (P < 0.05), 20.42% (P < 0.01) and 29.21% (P < 0.01), respectively. Dietary supplementation of AIgY reduced the size of adipocytes in all the three fat pads (P < 0.05). The meat color was improved whereas the marbling score, the intramuscular fat content, and pH45 of the longissimus muscle remained unaffected. Serum concentration of non-esterified fatty acids (NEFA) was significantly increased (P < 0.01) while urea-N content was reduced (P < 0.05). No alterations were detected for the serum levels of triacylglycerides (TG) and glucose. Serum concentrations of insulin and leptin were decreased by 26.19% (P < 0.05) and 26.53% (P < 0.05), respectively. LPL activity in adipose tissue was depressed significantly (P < 0.05) without affecting ME activity. This study demonstrates that dietary supplementation of AIgY can effectively improve growth and carcass composition of pigs and the changes of serum insulin and leptin levels as well as the tissue LPL activity may be involved in the acting mechanism.  相似文献   

6.
This review article deals with the various aspects of development of adipose tissues: fat partitioning between depots, chemical composition and cellularity of the various fatty tissues.Particular attention is paid to the changes between birth and maturity of these different characteristics. Total body fat (TBF) increases from 5% empty body weight at birth to approximately 26% in adult Friesian males. Fat partitioning between depots changes greatly during growth, with an increasing proportion of omental fat (7–13% of TBF), Kidney fat (4–9% TBF) and subcutaneous fat (6–17% of TBF) while intermuscular fat decreases (41–59%). All these changes are accompanied by increases in percentage of lipids in fatty tissues and in adipose cell diameter from 45 to 135 μ m, still in Friesian bulls.The fatness of animals of different breeds may vary from 48 kg to 85 kg carcass fat, when compared at the same body weight (450 kg). In the same breed, heifers have 26 to 60% more fat than bulls, while steers are intermediate between the two. These variations are accompanied by differences in cell size and also in fat partitioning, animals with a higher rate of fattening having a higher proportion of subcutaneous fat.Nutritional control of the rate of fat deposition is also discussed. This review is based on recent results from our laboratory together with those of other authors.  相似文献   

7.
The effect of varying feed intake and feeding pattern during the early postweaning period on growth, body composition and adipose tissue cellularity was studied in polygenic obese and control normal mice. Male mice were assigned to the following dietary treatments at 4.5 wk of age: stock diet fed ad libitum(AL), four palatable foods cafeteria-fed(CF), stock diet fed every 2 h by automatic feeders adjusted for maximum intake(MI), fed same procedure as MI but restricted to produce 70% of the gain of mice fed ad libitum(RE), and stock diet fed one meal/d the same amount fed RE mice(PM). Mice were killed after 5 wk on treatment. Cafeteria-fed control mice were heavier (P less than .05) than RE control mice, but they were not different (P greater than .05) from AL, MI and PM control mice, while CF obese mice were heavier and RE obese mice were smaller than AL, MI and PM obese mice (P less than .05). Cafeteria-fed mice were fatter than mice from all other treatments in both the obese and control lines. Maximum intake, PM and RE mice were fatter than AL mice but this effect was only significant in the obese line. Alterations in feeding pattern can affect body composition even though body weight may not show a correlated response. Cafeteria-fed obese mice had larger fat pads and more small (less than 40 micron) and large (greater than 110 micron) adipocytes than other obese mice. Results indicate that the difference in the development of obesity on cafeteria diet was due primarily to genetic effects while the increase in percentage fat after restriction on MI, PM and RE treatments was due mainly to the acute change of feeding pattern.  相似文献   

8.
A feedlot trial was conducted to determine the effect of dietary vitamin A concentration and roasted soybean (SB) inclusion on carcass characteristics, adipose tissue cellularity, and muscle fatty acid composition. Angus-crossbred steers (n = 168; 295 +/- 1.8 kg) were allotted to 24 pens (7 steers each). Four treatments, in a 2 x 2 factorial arrangement, were investigated: no supplemental vitamin A, no roasted soybeans (NANS); no vitamin A, roasted SB (20% of the diet on a DM basis; NASB); with supplemental (2,700 IU/kg) vitamin A, no roasted SB (WANS); and with supplemental vitamin A, roasted SB (WASB). Diets included high moisture corn, 5% corn silage, 10 to 20% supplement, and 20% roasted SB in the SB treatments on a DM basis. The calculated vitamin A concentration in the basal diet was < 1,300 IU/kg of DM. Blood samples (2 steers/pen) were collected for serum vitamin A determination. Steers were slaughtered after 168 d on feed. Carcass characteristics and LM composition were determined. Fatty acid composition of LM was analyzed, and adipose cellularity in the i.m. and s.c. depots was determined. No vitamin A x SB interactions were detected (P > 0.10) for cattle performance, carcass composition, or muscle fatty acid composition. Low vitamin A diets (NA) did not affect (P > 0.05) ADG, DMI, or G:F. Quality grade tended (P = 0.07) to be greater in NA steers. Marbling scores and the percentage of carcasses grading > or = Choice(-) were 10% greater for NA steers, although these trends were not significant (P = 0.11 and 0.13, respectively). Backfat thickness and yield grade were not affected (P > 0.26) by vitamin A supplementation. Composition of the LM was not affected (P > 0.15) by vitamin A or SB supplementation. Serum retinol at slaughter was 44% lower (P < 0.01) for steers fed NA than for steers supplemented with vitamin A (23.0 vs. 41.1 microg/dL). A vitamin A x SB interaction occurred (P < 0.05) for adipose cellularity in the i.m. depot; when no SB was fed, vitamin A supplementation decreased cell density and increased cell size. However, when SB was fed, vitamin A supplementation did not affect adipose cellularity. Adipose cellularity at the s.c. depot was not affected (P > 0.18) by vitamin A or SB treatments. Fatty acid profile of the LM was not affected by vitamin A (P > 0.05), but SB increased (P < 0.05) PUFA (7.88 vs. 4.30 g/100 g). It was concluded that feeding NA tended to increase marbling without affecting back-fat and yield grade. It appeared that NA induced hyperplasia in the i.m. but not in the s.c. fat depot.  相似文献   

9.
Seventy-two Rambouillet ewes were fed one of two different levels of energy and protein during gestation to determine the effects of maternal undernutrition on growth and development in their offspring. Levels of energy and protein for the two groups of ewes were: 70% of National Research Council (NRC) requirements 30 d prior to breeding and the first 100 d of gestation and then alfalfa hay fed at 70% of the average consumed by group 2, and 100% of NRC requirements 30 d prior to breeding and throughout gestation. Dissection data from the leg and muscle characteristics were recorded for each lamb. Neither dissected muscle and fat percentages nor proximate analyses of dissected muscles was influenced by ewe undernutrition during early pregnancy. However, the reduced conception rate, increased embryonic/fetal mortality, decreased birth weights and increased lamb mortality resulted in a severe reduction in kilograms of lamb per ewe bred. Feeding ewes 70% of NRC requirements during gestation resulted in lambs with heavier semitendinosus muscle weights, larger muscle fiber diameters and shorter sarcomere lengths than in lambs from adequately fed ewes. No influence of ewe diet, birth type or sex was observed for proportions of muscle fiber type (beta R, alpha R or alpha W). Therefore, low level feeding of ewes during early gestation had no detrimental effects on the carcass or muscle fiber characteristics of their lambs at slaughter.  相似文献   

10.
An experiment was conducted to 1) evaluate the effects of diet (alfalfa hay vs high concentrate) on adipose tissue cellularity and rates of in vitro lipogenesis and 2) determine if there was a relationship between in vitro lipogenic rates from acetate and lactate and rates of L- or D-lactate disappearance from plasma. Number of adipose cells/g of tissue decreased with time on experiment; however, hay-fed steers had fewer, but larger cells/g of subcutaneous adipose tissue compared with concentrate-fed steers (.78 +/- .04 vs 1.20 +/- .13 X 10(-6)/g, respectively). These results, however, are likely due to a higher (approximately 25%) intake of dry matter and metabolizable energy by the hay-fed steers. Carcass data obtained at slaughter (460 kg) indicated that the concentrate-fed steers had as much or more adipose tissue compared with the hay-fed steers. Characteristics describing D- or L-lactate disappearance from plasma were not highly correlated with lactate utilization for fatty acid synthesis. Utilization of acetate as a substrate for fatty acid synthesis in vitro was correlated (r = .64) with the rate of lactate utilization for fatty acid synthesis.  相似文献   

11.
Experiments were conducted to investigate biological variables that influence fat accretion in growing ram lambs. Carcass composition and adipose tissue development were measured in Columbia-sired ram lambs from 32.0 to 73.9 kg body weight. Five or six ram lambs were slaughtered every 2 mo, from 4 to 10 mo of age. The percentage of carcass fat-free dry matter decreased with age from 30.9 to 27.5% (P less than .05), while the percentage of carcass fat increased from 17.7 to 33.4%. Similarly, offal fat-free dry matter decreased with age (from 24.5 to 21.5), and there was nearly a threefold increase in the percentage of offal fat (P less than .05 for both measures). Subcutaneous adipocyte diameter and lipogenesis in vitro increased from 4 to 6 mo of age, and did not increase further with age. A bimodal distribution of adipocytes was apparent in the 4-mo-old lambs, but was not observed in any other age group. The presence of glucose in incubation media stimulated acetate incorporation into fatty acids in vitro in adipose tissue from 8- and 10-mo-old lambs. However, glucose did not affect the rate of lipogenesis from lactate. The data indicate early, rapid increases in carcass fat accretion, which corresponded to similar increases in lipogenesis and lipogenic enzyme activities.  相似文献   

12.
The detection of the illegal use of clenbuterol (CBL) as a growth promoter has relied on detecting residual concentrations of the drug in body fluids or tissues. Analysis of retinal extracts has recently been shown to considerably extend the detection period following withdrawal. The withdrawal periods required to eliminate residues from the liver and retina were investigated by medicating 20 cattle with CBL for 30 days; 6 control animals remained unmedicated. Residual concentrations were monitored throughout this period and for the subsequent 140 days. Concurrent changes in muscle areas and backfat thicknesses were recorded by ultrasound.CBL was detectable in liver up to the 56th day of withdrawal (0.35 ng/g, SD=0.5), but retinal concentrations remained well above detectable concentrations throughout the withdrawal period (22.5 ng/g, SD=6.5). There were small gains (3–4%) in the muscle areas of treated cattle during medication as compared to controls (p>0.05). These comparative gains remained during withdrawal. Backfat thicknesses in treated animals were 40% lower than in controls at the end of medication (p<0.01). However, by 70 days after withdrawal this difference had disappeared (p>0.05) owing to accelerated fat deposition in the treated group. The retina has been shown to be a highly effective target matrix for detecting CBL administration after long withdrawal periods.Abbreviations CBL clenbuterol - CIM cimaterol - EC European Community - EIA enzyme immunoassay - GC-MS gas chromatography-mass spectrometry - HRPo horseradish peroxidase - L. dorsi, Longissimus dorsi - MRL maximum residue level - SD standard deviation - SED standard error of the difference  相似文献   

13.
共轭亚油酸对肉仔鸡体组成和肉品品质的影响   总被引:1,自引:3,他引:1  
本试验旨在探讨日粮添加共轭亚油酸(CLA)对肉仔鸡体组成和肉品品质的影响。240只1日龄肉仔鸡随机分配到4个日粮处理组(0%、0.25%、0.5%和1%CLA),每个处理6个重复,每个重复10只鸡。试验结果表明:42d时,0.5%和1%CLA组肉仔鸡胸肌率显著高于对照组(P<0.05),1%CLA组肉仔鸡42d腿肌率显著高于对照组,肉仔鸡的腹脂率在各处理之间没有显著差异(P>0.05),1%CLA组肉仔鸡胸肌粗蛋白质粗脂肪比显著高于对照组(P<0.05)。0.5%、1%CLA组肉仔鸡胸肌滴水损失和丙二醛(MDA)含量显著降低(P<0.05)。试验结果表明,CLA可改善肉仔鸡屠体性状,增加鸡肉系水力和延长货架存放时间。  相似文献   

14.
This experiment was conducted to determine the effect of high levels of supplemental Cu (as (CuSO4).5H2O) on the serum lipid profile and carcass traits of goat kids. Fifteen Boer x Spanish wether goat kids (BW = 21.3 +/- 0.7 kg) were housed in individual pens and were assigned randomly to 1 of 3 treatments. Treatments consisted of 1) control (no additional supplemental Cu), 2) 100 mg of Cu/d, and 3) 200 mg of Cu/d. Copper sulfate was placed in gelatin capsules and inserted into the esophagus via a balling gun before the morning feeding. Animals were fed a high-concentrate (70:30 grain:hay) diet for 112 d. Serum lipid profile was determined on d 14 and 112, and BW was recorded after 4-h withdrawals from feed and water. After 112 d, animals were slaughtered, and carcass traits were measured. The left half of 12 carcasses and 9th to 11th rib sections from the right side of 15 carcasses were dissected into separable soft tissue and bone portions. The soft tissue portion was analyzed for moisture, ether extract, CP, and ash. Average daily feed intake decreased (linear; P = 0.05), and G:F increased (quadratic; P = 0.02) in the 100 mg of Cu/d group. Serum cholesterol and triglycerides did not change (P > 0.10); however, NEFA decreased (linear; P = 0.01) as supplemental Cu increased. No differences were observed (P > 0.10) in HCW, chilled carcass weight, or kidney and pelvic fat; however, 12th rib fat (linear; P = 0.01) and adjusted fat thickness (linear; P = 0.03) decreased as Cu supplementation increased. No differences (P > 0.10) in LM area were observed; however, percentage of boneless closely trimmed retail cuts increased (linear; P = 0.04) as Cu supplementation increased. The moisture (%) of the 9th to 11th rib sections increased (linear; P = 0.03), ether extract (%) decreased (linear; P = 0.02), and CP and ash (%) tended to increase (linear; P = 0.09 and 0.06, respectively) as Cu supplementation increased. Carcass composition measured using the left half of the carcass confirmed the values obtained through the 9th to 11th rib sections. Results of this study indicate that supplemental Cu can alter the serum lipid profile, carcass characteristics, and carcass composition of goat kids.  相似文献   

15.
Aspects of placental protein and energy metabolism were examined in pregnant ewes subjected to either thermoneutral (TN, 18 to 20 degrees C, 30% humidity, n = 7) or hot (H, 30 to 40 degrees C, 40% humidity, n = 5) temperatures through mid and late gestation. Fetal and placental weights and total content of protein, RNA, and DNA were reduced (P less than .001) in H ewes. Placental protein and RNA concentrations (mg/g) were not different, and DNA concentrations were slightly greater (P less than .1), in H vs TN ewes. Thus, heat seemed to greatly reduce total cell number and placentome size and only slightly decrease cell size. Ratios of RNA to DNA indicated a reduced capacity for protein synthesis in H placenta. However, in vitro fractional rates of protein synthesis in tissue slices from the fetal and maternal placenta and from the myoendometrium were not different between TN and H ewes. The H ewes had greater placental protein concentrations of hydroxyproline and glycine, perhaps suggesting a greater collagen content. In vitro oxygen consumption of fetal placenta, but not of maternal placenta or myoendometrium, was lower in H than in TN ewes. This lower oxygen consumption was partially due to a lower Na+,K+ ATPase-dependent oxygen consumption.  相似文献   

16.
This research aimed to determine whether outdoor free-range rearing during the winter (average ambient temperature of 5 degrees C) vs. indoor housing (22 degrees C) affects meat quality, muscle metabolic traits, and muscle fiber characteristics. Forty Large White gilts and barrows were blocked by weight within each gender (20 per gender) and allotted randomly into two groups of pigs, with one reared indoors (IN) in individual pens (2.6 m2) and the other reared outdoors (OUT) from December to March in a 0.92-ha pasture. Both groups had free access to the same grower-finisher diet from 23 to 105 kg. At slaughter, adipose (backfat [BF] and omental fat [OF]) and muscle tissues (longissimus muscle [LM], rectus femoris [RF], and semitendinosus [ST]) were obtained from the right side of each carcass. Muscle fibers were stained and classified on the basis of stain reaction as slow-oxidative (SO), fast oxidative-glycolytic (FOG), and fast glycolytic (FG); fiber area and distribution were determined. Also assessed were carcass characteristics, initial and ultimate pH, L*a*b* values, drip loss percent, glycolytic potential (GP), and intramuscular lipid content, as well as the fatty acid profile of each muscle and adipose tissue. The OUT pigs had lower (P < 0.05) ADG and leaner (P < 0.05) carcasses than IN pigs. Rearing environment did not (P > 0.63) affect the intramuscular lipid content of the ST, but intramuscular lipid content was lower (P < 0.01) in the LM and tended to be higher (P = 0.06) in the RF of OUT than in those of IN pigs. In the BF outer layer of the OUT pigs, the higher PUFA content was compensated by both a lower (P < 0.01) saturated and monounsaturated fatty acid (MUFA) content, whereas in the OF, LM, and dark portion of the ST, only the percentage of MUFA was decreased (P < 0.01). In all tissues of the OUT pigs, the linolenic acid content was higher (P < 0.01) and the n-6:n-3 ratio was lower (P < 0.01). The GP of all muscles was higher (P < 0.01), and the ultimate pH of the RF and ST was lower (P < 0.01), in OUT compared with IN pigs. Lightness (L*) values were lower (P < 0.01) in the LM. Percentages of drip loss were higher (P < 0.05) in the LM and light portion of the ST of OUT than in those of IN pigs. The LM and RF of OUT pigs had more (P < 0.01) FOG and fewer (P < 0.01) FG fibers than muscles of IN pigs. Results suggest that rearing pigs outdoors increases aerobic capacity of glycolytic muscles but has little concomitant influence on meat quality traits.  相似文献   

17.
1. The amino acid composition of the whole body protein of 28‐ and 56‐d‐old turkeys is reported.

2. There were some differences between the two ages; these could largely be reconciled by considering the likely differences in the proportion of feather protein.

3. The results were compared with similar values for the chicken and goose; overall there is a striking similarity, both in absolute concentrations and relative proportions of amino acids.  相似文献   


18.
19.
The subcutaneous adipose tissue of male broiler chickens fed diets containing either 5 ppm or 227 ppm of added copper was examined for its fatty acid composition and composition of triglyceride species. Small increases in monoenoic fatty acids at the expense of saturated fatty acids were found in birds fed high levels of copper. Significant increases in the triglyceride containing two monoenoic and one saturated fatty acids occurred and these replaced triglycerides composed to two saturated and one monoenoic fatty acids. These changes did not lead to changes in the melting properties of the fat.  相似文献   

20.
The effect of ethanol exposure on the fatty acid composition of brown and white adipose tissue in three successive rat progenies at the end of an experimental period (24 weeks) was studied. Ethanol-treated rats received a standard rat chow diet and 5, 10 and 15% ethanol in the ad libitum drinking fluid over 3 successive weeks. Then a concentration of 20% ethanol was maintained for 5 additional weeks up to the end of the experimental period. The males and females in the ethanol treated group were mated to obtain the 1st generation of offspring. Then female and male rats from the 1st generation were mated to obtain the 2nd generation. Finally, males and females from the 2nd generation were mated to obtain the 3rd generation of ethanol treated rats. Another group served as control and received only water and a standard rat chow diet. The control group was handled in the same way as the other experimental groups. In the 1st and 2nd generations the percentage of stearic acid (18:0) decreased and palmitoleic (16:1n7) and oleic acid (18:1n9) increased in both adipose tissues of ethanol-treated rats with respect to control. Additionally, n-3 and n-6 series were reduced both in brown and white adipose tissues. In the 3rd generation the fatty acid composition of the white adipose tissue was similar to that of control rats. Thus, no significant difference in essential fatty acids and oleic acid (18:1n9) were found. However, the fatty acid composition of the brown adipose tissue, in the 3rd generation, was similar to that observed in the 1st and 2nd generation. Thus, a decrease in essential fatty acids and an increase in oleic acid (18:1n9) was found. This suggests adaptation to ethanol consumption during successive progenies in white adipose tissue. However, in brown adipose tissue the values indicate a triglyceride storing during the thermogenesis, which is more important to newborns.  相似文献   

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