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1.
A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage.  相似文献   

2.
OBJECTIVE: To determine growth, morbidity, and mortality rates in dairy calves fed pasteurized nonsaleable milk versus commercial milk replacer and compare economics of feeding pasteurized nonsaleable milk versus commercial milk replacer in dairy calves. DESIGN: Clinical trial. ANIMALS: 438 dairy calves. PROCEDURE: Calves were assigned at 1 to 2 days of age to be fed pasteurized nonsaleable milk or a commercial milk replacer until weaned. Body weight was measured at the time of study enrollment and at the time of weaning, and any medical treatments administered and deaths that occurred prior to weaning were recorded. A partial budget model was developed to examine the economics of feeding pasteurized nonsaleable milk versus commercial milk replacer. RESULTS: Calves fed conventional milk replacer had significantly lower rates of gain (-0.12 kg/d [-0.26 lb/d]), lower weaning weights (-5.6 kg [-12.3 lb]), higher risk for treatment during the summer and winter months (odds ratio [OR], 3.99), and higher risk of death during the winter months (OR, 29.81) than did calves fed pasteurized nonsaleable milk. The estimated savings of feeding pasteurized nonsaleable milk, compared with milk replacer, was dollars 0.69/calf per day. The estimated number of calves needed to economically justify the nonsaleable milk pasteurization system was 23 calves/d. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that dairy calves fed pasteurized nonsaleable milk have a higher growth rate and lower morbidity and mortality rates than do calves fed conventional milk replacer. Feeding pasteurized nonsaleable milk could be an economically viable strategy for dairy calf producers.  相似文献   

3.
Growth rates during rearing affect the age and body weight (BW) of replacement heifers at first calving. Diet and disease can affect growth via altered metabolic hormone concentrations, but are difficult to monitor accurately on commercial farms. This study investigated the effect of management and metabolic indices (IGF-I, insulin, glucose and urea) on the growth rate of 509 Holstein-Friesian heifers on 19 UK dairy farms. Size (BW, heart girth, height and crown-rump length) was measured at approximately 1, 6 and 15 months. The mean daily weight gain up to 6 months for all calves was 0.77 kg/day, with extreme variability both between cohorts of calves (range 0.49–1.02 kg/day) and between individual calves within farms (range 0.45–1.13 kg/day). Growth was enhanced by supplemental colostrum, by milk replacer as opposed to whole milk and by ad libitum milk feeding and was reduced by gradual weaning and dehorning after weaning. Larger group size slowed growth before weaning (>6 calves) but increased it post-weaning (>20 calves). These management differences were reflected in altered plasma IGF-I concentrations, which were positively associated with growth throughout the rearing period. Larger calves at 1 month had a greater weight gain up to 6 months. Sub-optimum growth of some heifers within each cohort was established at an early age and resulted in animals reaching the start of breeding at an inadequate size (BW range 209–498 kg at 15 months). This could be alleviated by altered management strategies and improved monitoring of growing heifers.  相似文献   

4.
代乳粉用于早期断奶犊牛的效果研究   总被引:14,自引:0,他引:14  
犊牛使用代乳品可以节省鲜奶,降低饲养成本,控制疾病的发生,促进消化系统的发育。试验用24头犊牛做试验,60日龄断奶。结果表明,代乳品组犊牛增重47.55千克;对照组增重41.72千克;吃代乳品的犊牛在30-60日龄的日增重达到1026克,高于对照组103克。吃代乳品的犊牛每增重1千克的直接饲料成本为15.13元,比鲜奶组犊牛低2.14元/千克。  相似文献   

5.
The objective was to study the growth potential of Sahiwal calves given milk or milk replacer with or without concentrates. For this purpose, forty-eight Sahiwal calves were divided into four groups of 12 animals each with equal sex ratio. In each group, the calves were offered either milk or a milk replacer (MR) at a rate of 10% of their body weight adjusted weekly. In addition to this, calves were fed either a starter ration plus Egyptian clover hay (SR + H) or hay only (H) until the end of trial. The milk or MR was withdrawn gradually from day 56 until animals were weaned completely by day 84. Calves offered milk grew faster than those offered MR (357 ± 9 vs. 162 ± 9 g/day; p < 0.05) and displayed higher weaning weights (51.6 ± 0.8 vs. 35.2 ± 0.8 kg; p < 0.05). The calves offered SR + H grew faster (311 ± 9 vs. 208 ± 9 g/day; p < 0.05) and displayed higher weaning weights (48.7 ± 0.8 vs. 38.1 ± 0.8 kg; p < 0.05) than those fed H alone. Calves offered milk plus SR + H showed the highest growth rate and weaning weights (401 ± 13 g/day and 56.3 ± 1 kg, respectively). The lowest growth rate and weaning weights were observed in calves offered MR and H only (115 ± 13 g/day and 30.3 ± 1 kg, respectively). Calves offered the MR had higher number of scour days than those offered milk (13.5 vs. 3.3). The feeding of whole milk in combination with the starter ration and hay resulted in superior growth rates, higher weaning weights, and healthier calves than the other feeding regimens.  相似文献   

6.
旨在评价饲喂代乳粉对早期断奶犊牛生长及培育成本的影响。选取体重相近的新生犊牛45头,随机分为试验1组、试验2组和对照组;试验1组饲喂A品牌代乳粉,试验2组饲喂B品牌代乳粉,对照组饲喂牛场产鲜牛奶;测定各组实验犊牛的出生体重、1月龄体重和50日龄断奶体重;计算并比较各组犊牛培育成本。结果表明,各组犊牛的出生体重和1日龄体重差异不显著(P〉0.05);试验1组和试验2组犊牛的50日龄断奶体重分别比对照组增加5.12、2.86 kg,且试验1组与对照组相比差异显著(P〈0.05);试验1组和试验2组犊牛的平均日增重分别比对照组增加0.14、0.07 kg,且试验1组和对照组相比差异显著(P〈0.05);试验1组与试验2组平均每头犊牛分别比对照组节约饲养成本198.8、222.0元。综上提示,使用代乳粉能够促进犊牛生长,降低犊牛的培育成本,提高养殖场的经济效益。  相似文献   

7.
A 3-yr study was conducted to evaluate the effects of calving system, weaning age, and postweaning management on growth and reproduction in beef heifers. Heifer calves (n = 676) born in late winter (average birth date = February 7 +/- 9 d) or early spring (average birth date April 3 +/- 10 d) were weaned at 190 or 240 d of age, and heifers born in late spring (average birth date May 29 +/- 10 d) were weaned at 140 or 190 d of age. Heifers were managed to be first exposed to breeding at approximately 14 mo of age. After weaning, the calves were randomly assigned to treatments. Heifers on the constant gain treatment were fed a corn silage- and hay-based diet. Heifers on delayed gain treatments were placed on pasture but were fed grass hay or a supplement, or both, depending on the forage conditions. Three months before their respective breeding seasons, delayed gain heifers were moved to drylot and fed a corn silage- and barley-based diet (late winter or early spring) or moved to spring rangeland (late spring). The data were analyzed using mixed model procedures with calving system, weaning age, and postweaning management options creating 12 treatments. Average daily gain was 0.36 +/- 0.05 (SED) kg/d less (P < 0.001) for delayed gain heifers during the initial phase, whereas these heifers gained 0.44 +/- 0.03 kg/d more (P < 0.001) than constant gain heifers during the last 90 d before breeding. Body weights at the beginning of the breeding season did not differ (P = 0.97) between constant gain and delayed gain heifers but were affected by calving system and weaning age, reflecting some of the differences in initial BW. Prebreeding BW for heifers weaned at 190 d of age were 36 +/- 6.4 kg heavier (P < 0.001) for those born in late winter and early spring compared with late spring and were 388, 372, and 330 kg for heifers weaned in October at 240, 190, or 140 d of age (linear effect, P < 0.001). The proportion of heifers exhibiting luteal activity at the beginning of the breeding season was not affected (P = 0.57) by treatment. Approximately half of the heifers were randomly selected for breeding. Treatment had no effect (P = 0.64) on pregnancy rates. In conclusion, heifers from varied calving systems and weaning strategies can be raised to breeding using either constant or delayed gain strategies without affecting the percentage of heifers cycling at the beginning of the breeding season. These results suggest that producers have multiple options for management of heifer calves within differing calving systems.  相似文献   

8.
A 3-yr study evaluated late winter (Feb), early spring (Apr), and late spring (Jun) calving systems in conjunction with varied weaning strategies on beef cow and calf performance from Northern Great Plains rangelands. Crossbred cows were randomly assigned to one of three calving systems (on average n= 168.calving system(-1).yr(-1)) and one of two weaning times (Wean 1, 2) within each calving system. The Feb and Apr calves were weaned at 190 and 240 d of age, whereas Jun calves were weaned at 140 and 190 d of age. Breeding by natural service occurred in a 32-d period that included estrous synchronization. Cows were managed throughout the year as appropriate for their calving season. Quantity and quality of hay and supplements were provided based on forage and weather conditions, physiological state of the cows, and available harvested feed resources within a year. After weaning, two-thirds of the early weaned steers were fed in confinement in Montana, and one-third were shipped to Oklahoma and were grazed or fed forage. One-half of the early weaned heifers grazed seeded pastures, and the other half was fed in confinement. Early weaned calves were weighed on approximately the same day as late-weaned calves. Birth weight and overall rate of gain from birth to weaning did not differ for calves from the three calving systems. Calf weaning weight differed by weaning age within calving system (P = 0.001), and calves from the Jun calving system that were weaned at 190 d of age tended (P = 0.06) to be lighter than calves of the same age from the Feb or Apr calving systems. Cow BW change and BCS dynamics were affected by calving system, but the proportion of cows pregnant in the fall was not. Cows suckled until later dates gained less or lost more BW during the 50 d between the first and second weaning than dry cows during this period. The previous year's weaning assignment did not affect production in the following year. Estimated harvested feed inputs were less for the Jun cows than for the Feb and Apr cows. We conclude that season of calving and weaning age affect outputs from rangeland-based beef cattle operations.  相似文献   

9.
10.
The influence of silage:concentrate ratio (energy concentration) on voluntary feed intake, growth rate, feed utilization, reproduction and subsequent milk yield in early calving dairy heifers was examined. Forty-eight heifers of the breed Black and White were divided into four groups fed clover—grass silage and concentrates ad libitum in the ratios 100:0, 75:25, 50:50 and 25:75 of Scandinavian feed units (Sc.f.u.).Below 200 kg liveweight the daily intake of dry matter increased with increasing level of concentrates. Above 200 kg there were no significant differences in dry matter intake. As a consequence of the energy concentration of the rations (70, 78, 89 and 96 Sc.f.u. per 100 kg dry matter), the intake of net energy increased with the amount of concentrates, and consequently the daily gain increased. The increase in daily gain with concentrate level decreased with increasing liveweight.Puberty always occurred at the same liveweight, whereas age at first oestrus decreased with increasing content of concentrates in the ration offered ad libitum. This was reflected in a lowering of the age at first calving from 23.9 to 20.2 months. There was no significant difference in average milk yield in the first lactation. The milk yield was relatively low in all groups, and possible explanations for this depression are discussed.  相似文献   

11.
Twelve artificially reared, male Holstein calves, ruminally cannulated at 53 d of age, were used in a split-plot design to study the effects of no milk replacer reduction (CON), or reduction by 30% (30R) or 60% (60R) of this value on alfalfa hay intake and digestibility, ruminal fermentation and digestive kinetics. Milk replacer reduction began at 53 d of age and continued until 135 d of age, after which no milk replacer was fed. All calves had ad libitum access to long-stemmed alfalfa hay from birth. Five collection periods were conducted at average calf ages of 72, 87, 108, 129 and 151 d. Reducing the amount of milk replacer fed resulted in a linear increase (P less than .05) in forage OM intake; however, total OM intake (forage + milk) was not different (P greater than .10) among milk reduction groups. Size of particles in feces exhibited quadratic effects in response to milk replacer reduction (P less than .05) but only in the small (less than 150 microns) size groupings. Ruminal pH and ammonia and individual VFA concentrations (except isobutyrate) were not altered by milk reduction (P greater than .10) but increased (P less than .01) with calf age. Milk replacer reduction had a quadratic effect (P less than .05) on fluid outflow rate from the rumen, increasing as milk replacer was reduced. Other fluid and particulate kinetic data, as well as NDF digestion rate and DM digestion showed no effects (P greater than .10) from milk replacer reduction but changed with calf age. Milk replacer reduction increased forage intake but had minimal effects on digestive variables evaluated, suggesting that intake of milk replacer by calves can be reduced by up to 60% without disturbing forage fermentation and passage.  相似文献   

12.
In a national survey of US dairy producers, only 2.7 ± 0.5% of Holstein dairy operations reported achieving recommended target ranges of age ≤ 24 months and body weight (BW) ≥ 550 kg at first calving. Allowing for wider target ranges, still only 14.6 ± 1.3% of Holstein dairy operations reported achieving age ≤ 25 months and BW ≥ 544.3 kg at first calving. Ages of individual first-calf heifers observed at calving were heavily skewed toward older individuals. Dairy producers reported an average age at first calving that was 1.3 months lower than the mean and 1.0 months lower than median age of first-calf heifers' observed calving on the operations. Stepwise logistic regression was used to identify the herd characteristics associated with producers reporting first calvings within the wider age and BW target ranges for Holsteins. Rolling herd average milk production ≥ 7711 kg/yr, using a computer for recordkeeping, and not tying preweaned heifers in a barn with cows, were associated with achieving the target BW and age at first calving.  相似文献   

13.
试验选取体重相近的荷斯坦奶牛犊牛24头,分为试验组和对照组2组,每组12头。试验组犊牛出生5 d内饲喂初乳,之后饲喂代乳粉至42日龄断奶;对照组一直饲喂牛奶至42日龄。结果表明,试验组平均日增重836 g,对照组平均日增重679 g,试验组比对照组日增重提高23.12%;试验期间,试验组胸围、体高、体长分别比对照组提高2.90、1.01、1.56 cm,差异不显著;试验组与对照组的管围无明显差异。说明代乳粉代替牛乳可以达到良好的生产效果。  相似文献   

14.
Groups of 20 Holstein Friesian (HF), 23 Dutch Red and White (DRW) and 20 Dutch Friesian (DF) heifers were fed a complete diet with only roughage (a mixture of grass and corn-silage) or the same mixture of roughage with 50% concentrates on a dry matter basis, from 2 months before the first calving until 10 months after calving.No significant breed-feed composition interactions were found for any of the characteristics.The HF, DRW and DF heifers differed significantly in feed intake and milk production. They consumed 4725, 4432 and 4476 kVEM, respectively, and produced 5331, 4562 and 4660 kg milk, respectively, with 3.96, 4.20 and 4.22% of fat, respectively, and 3.25, 3.49 and 3.40% of protein, respectively.The concentrates and roughage groups differed significantly in feed intake, milk production, average body weight and gain. The respective mean values for the concentrates and the roughage groups were: 5160 and 3928 kVEM, 5534 and 4168 kg milk, 4.00 and 4.26% fat, 3.52 and 3.24% protein, 542 and 506 kg body weight and 97 and 38 kg gain, respectively.HF heifers used 51% of their energy intake for milk production (milk energy), DF heifers 49% and DRW heifers 48%. Both feed composition groups used 49% of their energy intake for milk production, but the roughage group used 8% more of the energy intake for maintenance than the concentrates group, as a result of lower energy intake.  相似文献   

15.
This study was conducted to determine the effect of feeding high milk volumes on the growth rate, health and cross-sucking behaviour in group-fed Jersey calves. Three-day-old heifers (n = 120) in a seasonal calving dairy herd were randomly assigned to one of 6 treatment groups. Three groups received high milk volumes (HMV), consisting of ad libitum milk or milk replacer feeding twice a day, while 3 groups received restricted milk volumes (RMV), consisting of 2 l twice daily, during the pre-weaning period. After a pre-weaning period during which feeding was reduced to once daily, all calves were weaned at 42 days and monitored until 60 days of age. Adjusting for birth mass, birth date, dam parity and sire, average daily mass gain (ADG), both pre-weaning (days 0-42) and overall (days 0-60), was higher in HMV than in RMV calves (P < 0.001). After weaning, growth rates showed no differences and at 60 days of age the HMV calves maintained a 6.74 kg advantage in mean body mass (P < 0.001). The mean intake of dry starter feed was higher in RMV than in HMV calves. Overall feed conversion rate of HMV calves was 9.6 % better than RMV calves. However, the variable cost per kg mass gain was 12 % higher for HMV calves. In the RMV groups 75 % of calves showed cross-sucking behaviour pre-weaning and 18 % post-weaning, whereas in HMV calves the proportions were 2 % and 7 %, respectively. There was no significant effect of milk volume on the incidence of diarrhoea. We conclude that the feeding of high volumes of milk to Jersey calves has a positive effect on growth rate, without compromising health or reducing solid feed intake after weaning. However, the higher cost of such a feeding system may limit its implementation.  相似文献   

16.
Two experiments were conducted simultaneously to evaluate the effects of different concentrates to roughage ratios on growth performance and attainment of puberty in Friesian–Boran crossbred heifers. Weaned 50% Friesian–Boran crossbred female calves were used in both experiments with 25 and 20 calves in experiments I and II, respectively. In experiment I, the calves were offered diets with concentrate to roughage ratios of 50:50 (treatment 1) or 30:70 (treatment 2). In experiment II, the calves grazed for 8 h a day and supplemented with 2 kg hay and 1 kg concentrate per head per day (treatment 1) or only 2 kg hay per head per day (treatment 2). The concentrate mixture was composed of 34% wheat bran, 31% wheat middling, 31% noug cake, 3% limestone, and 1% salt. In experiment I, heifers fed a ration with 50% concentrate and 50% roughage had higher (P < 0.05) daily body weight gain (0.532 kg) and attained puberty at 221 kg (65% of the mature body weight) in 15 months, while heifers fed a diet with 30% concentrate and 70% roughage gained 0.434 kg/day and reached puberty at 247 kg (70% of the mature body weight), about 3 months later. Heifers in treatments 1 and 2 of experiment II reached puberty 5 and 12 months later, respectively, than those in experiment I. In experiment II, heifers given 1 kg of concentrate supplement had higher (P < 0.05) daily body weight gain (0.346 kg) than those given only 2 kg hay in addition to grazing (0.278 kg). Growth rate of crossbred heifers was enhanced and age at puberty was reduced by changing the rearing management from outdoor to indoor and with increasing level of concentrate in the ration. This helps to bring the dairy heifer into production earlier and enhance to the overall productivity of the dairy industry.  相似文献   

17.
22头体重相近的荷斯坦犊牛随机分为2组,试验组饲喂代乳料,对照组饲喂新鲜牛奶。经60d的饲喂试验发现,试验组增重比对照组多5.3kg/头,且差异极显著(P<0.01),日增重比对照组提高了88.3g/d,差异极显著(P<0.01)。  相似文献   

18.
The aim of this study was to investigate the impact of weight gain of calves within the first 3 weeks of life on health status and subsequent performance. Holstein bull calves were reared either intensively (IR; individual hutches and ad libitum milk feeding for the first 3 weeks of life; n = 24), or according to the established protocol [ER; 4 l milk/day in hutches during week 1 and 720 g/day milk replacer (MR) from day 8 to 21 in a group pen; n = 24]. Water, hay and concentrates were freely available to all calves. From week 4, calves of both groups were housed together in a group pen and fed 720 g MR/day; step‐down weaning was performed between week 5 and 10. Key metabolic blood parameters were analysed on day 2, 12, 21 and 70 of life. After weaning, all animals were fed concentrates and corn silage until slaughter at an age of 8 months. Within the first 3 weeks, average daily weight gain was threefold higher in IR calves in relation to ER calves (1.28 vs. 0.38 kg/day, p < 0.001). Neither incidence nor duration of scouring differed significantly between groups. Starter intake (week 4–10) was higher in IR calves in relation to ER calves (49.7 vs. 38.0 kg/calf, p = 0.006). Serum glucose, urea, albumin and insulin were higher at an age of 21 days in IR calves in relation to ER calves; no differences were obvious at an age of 70 days. Plasma GH and IGF‐I concentrations revealed an uncoupling of the somatotropic axis in ER calves within the first 3 weeks of life. At slaughter, body weight of IR calves tended to be higher than that of the ER calves (320 vs. 309 kg, p = 0.07). In conclusion, intensive feeding and individual housing during the first 3 weeks of life had positive long‐term effects on subsequent performance.  相似文献   

19.
Thirty-nine Holstein steer calves were assigned to one of five treatments at birth and individually fed for 200 d with milk replacer reconstituted to equal the fat and protein concentration of beef cow milk. Treatment levels were the quantities of reconstituted milk fed per day based on lactation curves, which were based on peak milk levels (PML) of 2.72, 5.44, 8.16, 10.88, and 13.6 kg/d, respectively. In addition to reconstituted milk, chopped alfalfa hay was offered ad libitum to allow for maximal voluntary forage consumption. All calves were fed a high-energy diet postweaning until they reached a similar degree of fatness in the 12th rib (4 to 5% chemical fat) as determined by ultrasound. There were differences (P < 0.05) among groups in weaning weight, preweaning ADG, age, and weight at slaughter. During the preweaning phase, there was a linear relationship (P < 0.01) for daily milk and forage DE intake; however, DE intake per unit of BW did not differ across treatments (P = 0.06). Increasing PML resulted in a linear (P < 0.01) decrease in alfalfa hay intake in the preweaning phase, and G:F increased quadratically (P < 0.01). During the postweaning phase, preweaning milk intake had no meaningful effect on postweaning ADG, but overall ADG had a linear relationship (P < 0.01) with preweaning milk level. There was no effect of PML on the 12th-rib lipid percent, marbling score, or quality grade, but protein and fat concentration in the carcass and empty BW increased linearly (P < 0.01) with PML. The group fed at 2.72 kg/d PML was 58 kg lighter (P = 0.03) and required 34 d more (P < 0.01) to reach the predetermined degree of fatness at slaughter than the group fed at 13.6 kg/d PML, suggesting that increased milk production by the dam can decrease the number of days to the slaughter weight at which a similar rib lipid concentration is reached.  相似文献   

20.
Forage systems for production of stocker steers in the upper south   总被引:1,自引:0,他引:1  
The southern states produce large numbers of beef calves that are generally weaned and sold in autumn. Keeping calves in this region beyond weaning to graze high-quality forages through a stocker cattle phase could improve profitability. Autumn-weaned Angus crossbred steers were allocated by breeding and weight to four forage systems that began in mid-November and continued through mid-October as follows: System 1, tall fescue (Festuca arundinacea Schreb.) and Kentucky bluegrass (Poa pratensis L.)-white clover (Trifolium repens L.); System 2, tall fescue, caucasian bluestem (Bothriochloa caucasica [Trin.] C. E. Hubbard) and tall fescue-red clover (Trifolium pratense L.); System 3, orchardgrass-alfalfa and bluegrass-white clover; and System 4, rye (Secale cereale L.), soybeans (Glycine max)-foxtail millet (Setaria italica), and bluegrass-white clover. All steers were supplemented with hay or silage previously cut from their respective systems when forage for grazing was limited. System 2 which used stockpiled tall fescue for winter grazing and caucasian bluestem for summer forage plus fescuered clover for hay and grazing in a three-paddock system, resulted in greater (P < .01) gain per hectare and per steer, more grazing days, and reduced stored forage requirements and produced more surplus feed than the other systems tested. Gains per hectare for Systems 1 through 4 were 454, 554, 472, and 487 kg (SE = 18), respectively. Harvested forage from Systems 1, 2, and 3 met needs for stored forages but System 4 required additional "purchased" hay. Stored forage was fed for 61, 38, 112, or 104 d for Systems 1 through 4, respectively. Within the physio-climatic region of this experiment, a simple three-paddock system based on cool- and warm-season perennial forages could improve beef production per unit of land area while reducing inputs of labor and equipment.  相似文献   

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