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1.
Height differences between the two Koreas were injected into the U.S. presidential debate. The purpose of this article is to report briefly the height, weight, and body mass index (BMI) differences between North and South Korean children by using previous sources and new data. This study employs South Korean data published by the Korean Research Institute for Standards and Science in 1997 and by the Korean Agency for Technology and Standards in 2004, comparing them to North Korean data stemming from the 1997 and 2002 nutritional surveys conducted by the United Nations. Furthermore, this article makes use of anthropometric measurements of North Korean refugee children immigrating to South Korea from 2000 to 2007. In 1997, South Korean preschool children were found on average to be 6-7 cm (2-3 in.) taller and about 3 kg (6.6 pounds) heavier than their Northern counterparts; in 2002, the average gap was about 8 cm (3 in.) and 3 kg (6.6 pounds), and the BMI gap was about 1. North Korean boys and girls escaping to South Korea were also found to be on average about 3-4 cm (1-1.6 in.) shorter and 1 kg (2.2 pounds) lighter than their Southern peers.  相似文献   

2.
The association between body mass index (BMI) categories and mortality remains uncertain. Using three National Health and Nutrition Examination Surveys covering the 1971–2006 period for cohorts born between 1896 and 1968, this study estimates separately for men and women models for year-of-birth (cohort) and year-of-observation (period) trends in how age-specific mortality rates differ across BMI categories. Among women, relative to the normal weight (BMI 18.5–24.9 kg/m2), there are increasing trends in mortality rates for the overweight (BMI 25–29.9) or obese (BMI ≥ 30). Among men, mortality rates relative to the normal weight decrease for the overweight, do not change for the moderately obese (BMI 30–34.9), and increase for the severely obese (BMI ≥ 35). Period and cohort trends are similar, but the cohort trends are more consistent. In the latest cohorts, compared with the normal weight, mortality rates are 50 percent lower for overweight men, not different for moderately obese men, and 100–200 percent higher for severely obese men and for overweight or obese women. For U.S. cohorts born after the 1920s, a lower overweight than normal weight mortality is confined to men. I speculate on possible reasons why the mortality association with overweight and obesity varies by sex and cohort.  相似文献   

3.
KUCZMARSKI, ROBERT J, MARGARET D CARROLL, KATHERINE M FLEGAL, RICHARD P TROIANO. Varying body mass index cutoff points to determine overweight prevalence among U. S. adults: NHANES III (1988 to 1994). Body mass index (BMI; kg/m2) distributions are commonly reported in the scientific literature to describe weight for stature. These data are collected for various groups of subjects in local health and body composition studies, and comparisons with national distributions are often desirable. Tabular data for population prevalence estimates from thethird National Health and Nutrition Examination Survey (NHANES III, 1988 to 1994) at selected gender- and age-specific BMI levels ranging from <18. 0 to >45. 0 are presented and compared with various examples of BMI criteria reported in the scientific literature. NHANE HI was a statistically representative national probability sample of the civilian, noninstitutionalized population of the United States in which height and weight were measured as part of a more comprehensive health examination. The implications of varying population prevalence estimates based on varying BMI cutoff points are briefly discussed for selected examples including World Health Organization overweight/obesity criteria and the U. S. Dietary Guidelines for Americans. The median BMI for U. S. adults aged 20 years and older is 25. 5 kg/m2. Median stature and weight for men are 175. 5 cm and 80. 0 kg and for women are 161. 6 cm and 65. 6 kg, respectively. The percentage of the population with BMI <19. 0 is 1. 6% for men, 5. 7% for women; BMI 19. 0 to <25. 0 is 39. 0% for men, 43. 6% for women; BMI 25. 0 is 59. 4% for men, 50. 7% for women. An estimated 97. 1 million adults have a BMI 25. 0. Additional prevalence estimates based on other BMI cutoff points and ages are presented.  相似文献   

4.
The use of mid prepartum shearing has been described as a possible tool to increase the weight of the lambs at birth and at weaning. The effect of prepartum shearing (53 days of gestation) on production and chemical composition of milk, weight of the lambs at birth and weaning and growth rate were evaluated in this trial. Twenty Polwarth ewes were inseminated with rams of the same breed in May (autumn), 2009. All ewes bore singletons and were maintained together under cultivated grazing conditions, during the experimental period. The ewes were allocated to two treatments groups, based on expected day of parturition, body weight and BCS of the dams. Ten ewes were shorn at 53 days of gestation (S53) and 10 ewes were kept unshorn during gestation (US). Milking of the ewes was recorded 7 days after parturition, and this was repeated weekly for 15 weeks. Milk production of the S53 ewes was 22.2% higher (P < 0.05), when compared to US control ewes - with no change in the milk composition. At lambing, the lambs born to the S53 ewes were 1.41 kg (P < 0.05), and at weaning 4.5 kg heavier (P < 0.05), than lambs born to US ewes. In conclusion, it can be said that the higher weaning weight of the S53 lambs was the result of both a higher birth weight and an increased growth rate up to weaning in part, due to an improved milk production of the ewes.  相似文献   

5.
This study aimed to: a) investigate the differences in workload and readiness between two junior female national basketball teams competing at different European Championships (EC); b) compare workload, readiness and match performance for players with longer and shorter playing times, and; c) examine the relationship between workload, readiness and match performance variables. Under-18 (U18) (n = 10, height = 179.9 ± 6.6 cm, body mass = 70.2 ± 5.1 kg) and under-20 (U20) female national basketball teams (n = 11, height = 178.4 ± 8.8 cm, body mass = 73.0 ± 9.7 kg) were monitored during congested match schedules encompassing 7 matches within 9 days. Daily workload was determined via the session rating of perceived exertion (sRPE workload); readiness was measured by heart-rate variability (HRV) and well-being (WB); and match performance was assessed using the efficiency statistic and playing time. Analysis of workload and readiness during the EC showed no statistically significant between-team differences in any variables except WB for the U18 team, which was lower on Day 8 compared to the U20 team (p = 0.03; effect size [ES] = large). Players accumulating longer playing time showed a higher sRPE workload (p = 0.01, ES = moderate) and efficiency statistic (p = 0.04, ES = moderate) while no readiness variable differed significantly (p > 0.05) compared to players with shorter playing time. Trivial-to-small correlations were observed between workload, readiness and match performance variables. The study shows that junior female basketball players were able to cope with a congested schedule of 7 matches in 9 days irrespective of the competition context or individual differences in workload. Finally, combining objective and subjective methods to assess workload and readiness is recommended due to the weak relationships observed between these methods.  相似文献   

6.
Body height often serves as a proxy for economic progress. In this paper, we investigate the evolution of average height and height dispersion in Poland based on full administrative data on body height (n = 36,393,246). Especially for the cohorts between 1920 and 1950, we discuss the caveat of shrinking. In the cohorts born between 1920 and 1996, the average height of men increased by 10.15 cm, while the average height of women rose by 8.18 cm. Height increase was fastest in the years 1940 – 1980. After the economic transition, body height stagnated. Post-transition unemployment had negative effects on body height. Height declined in municipalities where there were State Agricultural Farms. Height dispersion decreased in the first decades under investigation and increased after the economic transition.  相似文献   

7.
OBJECTIVE--To discover whether reduced fetal and infant growth is associated with non-insulin dependent diabetes and impaired glucose tolerance in adult life. DESIGN--Follow up study of men born during 1920-30 whose birth weights and weights at 1 year were known. SETTING--Hertfordshire, England. SUBJECTS--468 men born in east Hertfordshire and still living there. MAIN OUTCOME MEASURES--Fasting plasma glucose, insulin, proinsulin, and 32-33 split pro-insulin concentrations and plasma glucose and insulin concentrations 30 and 120 minutes after a 75 g glucose drink. RESULTS--93 men had impaired glucose tolerance or hitherto undiagnosed diabetes. They had had a lower mean birth weight and a lower weight at 1 year. The proportion of men with impaired glucose tolerance fell progressively from 26% (6/23) among those who had weighted 18 lb (8.16 kg) or less at 1 year to 13% (3/24) among those who had weighed 27 lb (12.25 kg) or more. Corresponding figures for diabetes were 17% (4/23) and nil (0/24). Plasma glucose concentrations at 30 and 120 minutes fell with increasing birth weight and weight at 1 year. Plasma 32-33 split proinsulin concentration fell with increasing weight at 1 year. All these trends were significant and independent of current body mass. Blood pressure was inversely related to birth weight and strongly related to plasma glucose and 32-33 split proinsulin concentrations. CONCLUSIONS--Reduced growth in early life is strongly linked with impaired glucose tolerance and non-insulin dependent diabetes. Reduced early growth is also related to a raised plasma concentration of 32-33 split proinsulin, which is interpreted as a sign of beta cell dysfunction. Reduced intrauterine growth is linked with high blood pressure, which may explain the association between hypertension and impaired glucose tolerance.  相似文献   

8.
9.
Dias Quiterio, AL, Canero, EA, Baptista, FM, and Sardinha, LB. Skeletal mass in adolescent male athletes and nonathletes: relationships with high-impact sports. J Strength Cond Res 25(12): 3439-3447, 2011-This study examined the relationships between the practice of different categories of sports (high-impact vs. nonimpact) and bone status in adolescent male athletes and investigated differences from an age-matched control group. A total of 54 adolescent male athletes and 26 adolescent nonathletes were evaluated. Bone mineral density, bone mineral content (BMC), and bone area at the whole-body, limbs, and lumbar spine were determined by dual-energy x-ray absorptiometry, along with total and regional fat-free mass and body fat. The high-impact group included 34 athletes: 9 gymnasts, 18 basketball players, and 7 handball players (age: 15.7 ± 1.6 years; weight: 72.0 ± 15.0 kg; height: 178.5 ± 12.5 cm). The nonimpact group consisted of 20 swimmers (age: 16.4 ± 2.5 years; weight: 66.9 ± 10.4 kg; height: 173.7 ± 10.9 cm). The nonathletic control group included 26 male adolescents (age: 15.9 ± 2.8 years; weight: 64.7 ± 16.3 kg; height: 168.6 ± 15.1 cm). No differences were observed between the nonimpact and the control group in all bone variables, before and after adjustments for maturation level, body weight, and height (p > 0.05). After adjustments for these variables, the high-impact group displayed greater bone mass in most of the measured sites when compared to the other 2 groups (p < 0.001). Subjects in the nonimpact group showed lower values of BMC, particularly in the lower limbs, than both the high-impact and the nonathletic control groups (p < 0.05) after adjustments for maturation, high, and fat-free mass. This study reinforces the positive associations between high-impact physical activities and skeletal health in adolescent boys.  相似文献   

10.
The genetic trends in fitness (inbreeding, fertility and survival) of a closed nucleus flock of Menz sheep under selection during ten years for increased body weight were investigated to evaluate the consequences of selection for body weight on fitness. A mate selection tool was used to optimize in retrospect the actual selection and matings conducted over the project period to assess if the observed genetic gains in body weight could have been achieved with a reduced level of inbreeding. In the actual selection, the genetic trends for yearling weight, fertility of ewes and survival of lambs were 0.81 kg, –0.00026% and 0.016% per generation. The average inbreeding coefficient remained zero for the first few generations and then tended to increase over generations. The genetic gains achieved with the optimized retrospective selection and matings were highly comparable with the observed values, the correlation between the average breeding values of lambs born from the actual and optimized matings over the years being 0.99. However, the level of inbreeding with the optimized mate selections remained zero until late in the years of selection. Our results suggest that an optimal selection strategy that considers both genetic merits and coancestry of mates should be adopted to sustain the Menz sheep breeding program.  相似文献   

11.
This study evaluates the physical and physiological ability of selected soccer players of Kunimi High School in Nagasaki Prefecture, Japan. The Kunimi team is famous for its intensive training, and had won the championship of the All Japan High School Soccer Tournament six times by 2003. We measured physique, body composition, and maximal oxygen uptake of 72 members aged between 16 and 18 years old between 1986 and 1994. They consisted of 66 outfield players (12 forward players, 23 midfielders, 31 defenders) and 6 goalkeepers. Body density was measured by the under-water weighing method, and Brozek's equation was applied to calculate percentage body fat (%Fat, %), fat-free mass (FFM, kg), FFM/height (FFM/Ht, kg.m(-1)), and FFM index (FFM/Ht(3), kg.m(-3)). The following results were obtained: 1. The average of 66 outfield players was 172.7 cm of height, 64.6 kg of weight, 54.0 cm of girth of thigh, and 90.0 cm of girth of hip, 9.3% of %Fat, 58.6 kg of FFM, 33.9 kg.m(-1) of FFM/Ht and 113.8 kg.m(-3) of FFM index. The mean vital capacity was 4.25 L and total lung capacity was 5.58 L. The mean maximal ventilation was 138.7 L.min(-1), VO(2)max was 3.95 L.min(-1), and VO(2)max/Wt was 61.4 ml.kg(-1).min(-1). 2. Goalkeepers were taller and heavier than outfielders, and had a smaller mean value of VO(2)max/Wt than outfielders (p<0.01). 3. For 23 out of the 72 players measured twice with an interval of about one year, FFM increased and %Fat reduced significantly, while V(E)max, VO(2)max and VO(2)max/Wt did not change. Kunimi players of the present study had as large a VO(2)max/Wt as local players, and a similar or slightly smaller VO(2)max/Wt than national-level players. They had similar %Fat and a similar VO(2)max/Wt with professional soccer players in England (Davis et al., 1992) while they had much smaller physiques.  相似文献   

12.
This study was designed to compare the effectiveness of small-sided handball games in combination with handball training (SSG group) versus high-intensity interval training in combination with handball training (HIIT group) on physical performance of young female handball players during pre-competitive period. Twenty-four young female handball players, who have a 6.17 ± 1.54 years training experience and competition in the national league participated in this study. SSG group (n = 12; age 16.06 ± 0.80 years, body mass 61.27 ± 3.68 kg, body height 1.64 ± 4.7 m, body mass index 22.7 kg/m2) while HIIT group (n = 12; 16.20 ± 1.28 years, body mass 62.46 ± 7.86 kg, body height 1.68 ± 6.8 m, body mass index 22 kg/m2). Both groups applied training programs twice-a-week for 8 weeks. Before and after the training programs physical performances were assessed: Countermovement jump (CMJ), Squat jump (SJ), Sprint on 0–10 m; Sprint on 0–20 m; Sprint on 0–30 m, Throwing medicine ball and total distance covered during the Yo-YoIRT1. After 8 weeks SSG and HIIT groups significantly improved CMJ, SJ, 0–20 m sprint, 0–30 m sprint, throwing medicine ball and Yo-YoIRT1 (p ≤ 0.05). However, significantly greater improvement was achieved in Yo-YoIRT1 (m) in HIIT group (28.40%) than SSG group (17.63%). These results indicate that SSG group and HIIT group equally improve of physical performances (jump, sprint and upper explosive strength) among young female handball players in pre-competitive period.  相似文献   

13.
An anthropometric assessment was conducted of 441 adults from six rural villages in southern Mali. As is typical for human populations, females are shorter and lighter than males. Both females (N = 320) and males (N = 121) are shorter and lighter than their U.S. counterparts. Mean weight in the sample is 53.4 +/- 8.5 kilos for females and 58.8 +/- 6.5 kilos for males. Mean height is 160.4 +/- 5.7 cm for females and 171.3 +/- 6.6 cm for males. The data for height in males are very similar to those reported from other surveys in Mali, and show no evidence for a positive secular trend in height. Mean body mass index (BMI) is 20.8 for females and 20.0 for males. These are lower than U.S. averages, but well above suggested cutoff points for malnutrition in adults. Average arm circumference is 26.5 cm for females and 26.4 cm for males. Females have relatively large arm circumferences due, in part, to the heavy manual labor they perform. Average head circumference is 53.0 cm for females and 54.8 cm for males. For both sexes, these values are more than 1 standard deviation (SD) below the U.S. means. Adult values for anthropometric measurements reflect childhood stresses of malnutrition and disease, and a lifetime of accommodation to a high-carbohydrate, low-protein diet, and hard physical labor. Females are significantly closer to the U.S. standards than males for weight, height, BMI, and arm circumference; these findings support the idea that females are buffered from environmental stresses relative to males. In addition, females exhibit significantly more variability than males for weight, arm circumference, and head circumference, but not for height, suggesting that variability in adult height does not reflect the presence or absence of female buffering or the level of environmental adversity.  相似文献   

14.
Most studies analysing the influence of socioeconomic deterioration on body size focus on the impact of food shortages and diseases on the growth in early childhood. To evaluate how socioeconomic conditions influence the growth during the adolescence, we tracked the body size of 15–19 year-olds over the last sixty years covering the socialist period (1951–1990), the war (1991–1995) and the transition to capitalistic economy. This study of Zagreb, Croatia, adolescent population provides information on the secular trend in height, weight and Body Mass Index (BMI) and examines their relation with Real Gross Domestic Product. From 1951 to 2010 the girls’ height approximately increased by 6.2 cm and weight by 6.8 kg, while the boys’ height increased by 12.2 cm and weight by 17.3 kg. Prior to 1991 mean BMI in girls was higher than in boys, but from 1991 on, the interrelation between the sexes has been opposite, possibly mirroring the cultural trends that started in mid-1970s and reflecting higher sensitivity of boys to the socioeconomic changes. In conclusion, the secular trend in body size over the investigated period reflects the positive economic trends interrupted by the war. The recent increase in BMI corresponds to the country's economic recovery and indicates the “nutrition transition”.  相似文献   

15.
Data on 550 healthy pregnant women, 550 healthy fathers and their healthy term neonates born from singleton pregnancies (37(+0) through 41(+6) week) during a one-year period were reviewed. Maternal mean age was 27.7 +/- 9.37 years, mean pregestational weight 64.0 +/- 9.50 kg, mean gestational weight gain 15.4 +/- 4.33 kg, mean height 169.7 +/- 5.81 cm, and mean gestational age 40.1 +/- 0.95 weeks. Paternal mean age was 31.4 +/- 6.22 years, mean weight 84.6 +/- 10.35 kg, and mean height 182.8 +/- 6.84 cm. Mean birth weight was 3,709.8 +/- 500.48 g and 3,562.5 +/- 443.02 g, and mean birth length 51.5 +/- 1.91 cm and 50.7 +/- 1.62 cm in male and female newborns, respectively, yielding a birth weight greater by 147.3 g and birth length by 0.8 cm in the former. Study variables showed statistically significant correlations: maternal age contributed to the significant correlation between maternal weight and parity, maternal pregestational weight, weight at delivery, gestational weight gain and body height correlated significantly with neonatal birth weight and birth length, gestational age correlated significantly with neonatal weight and length (p = 0.01 all), parity had no major impact (p > 0.05). Paternal height and weight correlated significantly with neonatal birth weight and birth length (p = 0.01). Study results pointed to a significant correlation of maternal pregestational weight, gestational weight gain and body height, and of paternal weight and height with the neonate birth weight and birth length.  相似文献   

16.
Turkish children and adolescents born in Northern Europe grow different from native Northern European children, but reference values for height, weight and BMI for these children do not exist. With this study, we intend to provide growth standards for German born Turkish children. Data were obtained from 797 Turkish children and adolescents born in Germany age 0-25.8 years (males), respectively 0-18.3 years (females). We generated synthetic reference values for height, weight, and BMI. The results show that Turkish children and adolescents are heavier after the age of 6 years, and that they remain short after puberty. Eighteen year old Turkish men, and 15-year-old Turkish women are shorter (males 175.2 cm vs. 180.4 cm, p < 0.05; females 159.3 cm vs. 165.0 cm, p < 0.05), and heavier than Germans. Six out of 53 young Turkish men and 9 out of 100 young Turkish women were obese. Twelve out of 53 young Turkish men (23%) and 18 out of 100 young Turkish women (18%) have fallen below the 3rd centile for height. It can be concluded that growth of Turkish children and adolescents born in Germany significantly differs from native children. Reference LMS values for body height, weight and BMI of German born Turkish boys and girls are presented.  相似文献   

17.
Leatherback turtles (Dermochelys coriacea) are endangered, and declining population trends suggest that they are vulnerable to becoming extinct in the Pacific Ocean. Population recovery depends on strong conservation measures (e.g., nest protection, reduction of bycatch, and foraging habitat preservation) and on how fast leatherbacks grow and reach maturity, making the latter of grave concern. The research reported here marks the first time that several leatherback turtles have been maintained in captivity for nearly 2 years, from hatchlings (6.31 ± 0.13 cm straight carapace length (SCL) and 46.0 ± 1 g) to juveniles (largest, 72.0 cm SCL and 42.65 kg). Leatherbacks maintained an average growth rate of 31.9 ± 2.8 cm year− 1 in SCL throughout the study period. A length-mass relationship of the form, mass (kg) = 0.000214 ? SCL (cm) 2.86, fitted our data and data from four other captive studies, 11 wild juveniles, and five studies of adult leatherbacks. Von Bertalanffy, Gompertz and logistic growth functions predicted age-at-maturity for leatherbacks of 16.1, 8.7 and 6.8 years, respectively. The accuracy of these age-at-maturity estimates is discussed in the light of skeletochronological studies as well as estimates obtained from conservation and genetic studies. Our data, in combination with data from sightings, suggest that leatherbacks spend their early years (0 to 5 years of age) growing in the warmer waters of the tropical and subtropical seas before entering cooler temperate waters. Information obtained from turtles incidentally captured in fisheries, supplemented with growth curve data, indicates that leatherbacks are vulnerable to entanglement or hooking in various pelagic gear types, such as drift gill nets and longline within 3 years from nest emergence. Consequently, leatherbacks are exposed to threats from marine fisheries for > 80% of their early life before carapace length characteristic of reproductive maturity is attained.  相似文献   

18.
In many mammal species with sexual dimorphism producing sons is energetically more demanding to the mother than producing daughters. Although some studies in humans have suggested that offspring born after a brother have a smaller birth weight and adult height when compared with those born after a sister, little is known about this intergenerational cost of producing sons. We aimed to study whether the sex of preceding sibling is associated with anthropometrics of the subsequent child at birth and in young adulthood. This population‐based study was carried out on two data sets derived from the Swedish registers. Information on birth weight and length was obtained for 752,723 children of both sexes. Adult weight, height and muscle strength were available for 506,326 men. Multiple linear regression analyses showed that boys and girls born after a brother were, respectively, 18 and 9 g lighter and 0.08 and 0.03 cm (P < 0.001) shorter at birth than those born after a sister. Adjustment for gestational age decreased the magnitude of the associations [10 g and 0.04 cm (P < 0.001) in men and nonsignificant estimates in women], suggesting that part of the lower mean birth weight and length of individuals born after a brother was due to a shorter gestation. In young adulthood, men with a preceding brother showed 0.16 kg more in weight, 0.3% higher body mass index (P < 0.001) and a trend towards reduced height and muscle strength. Our results suggest that even though the sex of the previous child is associated with the anthropometrics of the subsequent child, the effect sizes are very small questioning whether this mechanism has adaptive value in contemporary humans. Am J Phys Anthropol 154:471–478, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   

19.
OBJECTIVE--To study the effect of intrauterine growth and maternal physique on blood pressure in adult life. DESIGN--A follow up study of infants born 50 years previously whose measurements at birth were recorded in detail. SETTING--Preston, Lancashire. SUBJECTS--449 Men and women born in hospital in Preston during 1935-43 and still living in Lancashire. MAIN OUTCOME MEASURES--Placental weight, birth weight, and blood pressure at age 46 to 54 years. RESULTS--In both sexes systolic and diastolic pressures were strongly related to placental weight and birth weight. Mean systolic pressure rose by 15 mm Hg as placental weight increased from less than or equal to 1 lb (0.45 kg) to greater than 1.5 lb and fell by 11 mm Hg as birth weight increased from less than or equal to 5.5 lb to greater than 7.5 lb. These relations were independent so that the highest blood pressures occurred in people who had been small babies with large placentas. Higher body mass index and alcohol consumption were also associated with higher blood pressure, but the relations of placental weight and birth weight to blood pressure and hypertension were independent of these influences. CONCLUSIONS--These findings show for the first time that the intrauterine environment has an important effect on blood pressure and hypertension in adults. The highest blood pressures occurred in men and women who had been small babies with large placentas. Such discordance between placental and fetal size may lead to circulatory adaptation in the fetus, altered arterial structure in the child, and hypertension in the adult. Prevention of hypertension may depend on improving the nutrition and health of mothers.  相似文献   

20.
A simultaneous model for analysis of net energy intake and growth curves is presented, viewing the animal's responses as a two dimensional outcome. The model is derived from four assumptions: (1) the intake is a quadratic function of metabolic weight; (2) the rate of body energy accretion represents the difference between intake and maintenance; (3) the relationship between body weight and body energy is allometric and (4) animal intrinsic variability affects the outcomes so the intake and growth trajectories are realizations of a stochastic process. Data on cumulated net energy intake and body weight measurements registered from weaning to maturity were available for 13 pigs. The model was fitted separately to 13 datasets. Furthermore, slaughter data obtained from 170 littermates was available for validation of the model. The parameters of the model were estimated by maximum likelihood within a stochastic state space model framework where a transform-both-sides approach was adopted to obtain constant variance. A suitable autocorrelation structure was generated by the stochastic process formulation. The pigs’ capacity for intake and growth were quantified by eight parameters: body weight at maximum rate of intake (149-281 kg); maximum rate of intake (25.7-35.7 MJ/day); metabolic body size exponent (fixed: 0.75); the daily maintenance requirement per kg metabolic body size (0.232-0.303 MJ/(day×kg0.75)); reciprocal scaled energy density ; a dimensional exponent, θ6 (0.730-0.867); coefficient for animal intrinsic variability in intake (0.120-0.248 MJ0.5) and coefficient for animal intrinsic variability in growth (0.029-0.065 kg0.5). Model parameter values for maintenance requirements and body energy gains were in good agreement with those obtained from slaughter data. In conclusion, the model provides biologically relevant parameter values, which cannot be derived by traditional analysis of growth and energy intake data.  相似文献   

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