Femur Marrow Fat Research Articles

Vertebrae but not femur marrow fat transiently decreases in response to body weight loss in an 18-month randomized control trial.

Increased levels of bone marrow adipose tissue (BMAT) are negatively associated with skeletal health and hematopoiesis. BMAT is known to increase with age; however, the effect of long-term weight loss on BMAT is still unknown. In this study, we examined BMAT response to lifestyle-induced weight loss in 138 participants (mean age 48 y; mean body mass index 31kg/m2), who participated in the CENTRAL-MRI trial. Participants were randomized for dietary intervention of low-fat or low-carb, with or without physical activity. Magnetic resonance imaging (MRI) was used to quantify BMAT and other fat depots at baseline, six and eighteen months of intervention. Blood biomarkers were also measured at the same time points. At baseline, the L3 vertebrae BMAT is positively associated with age, HDL cholesterol, HbA1c and adiponectin; but not with other fat depots or other metabolic markers tested. Following six months of dietary intervention, the L3 BMAT declined by an average of 3.1%, followed by a return to baseline after eighteen months (p<0.001 and p=0.189 compared to baseline, respectively). The decrease of BMAT during the first six months was associated with a decrease in waist circumference, cholesterol, proximal-femur BMAT, and superficial subcutaneous adipose tissue (SAT), as well as with younger age. Nevertheless, BMAT changes did not correlate with changes in other fat depots. We conclude that physiological weight loss can transiently reduce BMAT in adults, and this effect is more prominent in younger adults. Our findings suggest that BMAT storage and dynamics are largely independent of other fat depots or cardio-metabolic risk markers, highlighting its unique functions.

Vertebrae But Not Femur Marrow Fat Transiently Decreases in Response to Body Weight Loss in an 18-Month Randomized Control Trial

Vertebrae But Not Femur Marrow Fat Transiently Decreases in Response to Body Weight Loss in an 18-Month Randomized Control Trial

Fatty Acid Composition of Proximal Femur Bone Marrow Adipose Tissue in Subjects With Systemic Lupus Erythematous Using 3T Magnetic Resonance Spectroscopy.

Systemic lupus erythematosus (SLE) is a chronic, inflammatory disease with common musculoskeletal manifestations, notably reductions in bone quality. Bone marrow adipose tissue composition and quantity has been previously linked to bone quality and may play a role in SLE pathophysiology but has not been thoroughly studied. To use magnetic resonance spectroscopy (MRS) to investigate bone marrow adipose tissue quantity and composition in proximal femur subregions of untreated SLE patients compared to controls and treated patients. Prospective. A total of 64 female subjects: 28 SLE, 15 glucocorticoid (GC)-treated SLE and 21 matched controls. Stimulated echo acquisition mode (STEAM) sequence at 3 T. MRS was performed at multiple echo times in the femoral neck and trochanter regions and fatty acids (FA) composition was computed. Intergroup comparisons were carried out using ANOVA. A P value < 0.05 was considered statistically significant. SLE patients had significantly higher saturated FA compared to controls in both the femoral neck (+0.12) and trochanter (+0.11), significantly lower monounsaturated FA in the trochanter compared to controls (-0.05), and significantly lower polyunsaturated FA in the femoral neck compared to both controls (-0.07) and SLE patients on GC therapy (-0.05). SLE patients have altered proximal femur marrow fat metabolism, which may reflect a manifestation of, or play a role in, the altered inflammatory response of these patients. 2 TECHNICAL EFFICACY: Stage 2.

Serum leptin as an indicator of fat levels in white-tailed deer (Odocoileus virginianus) in the southeastern USA.

Leptin is a hormone that plays a key role in regulating energy intake, appetite, and metabolism. In some mammals, leptin has been shown to circulate at levels proportional to body fat, which could make it useful for nonlethal evaluation of body condition. Leptin's usefulness for estimating fat levels (i.e., body condition) of white-tailed deer (Odocoileus virginianus) is unknown. We quantified serum leptin concentrations in a sample of free-ranging, female deer collected in July 2008 and March 2009 from coastal North Carolina, USA. We compared leptin concentrations with kidney fat index, femur marrow fat index, and kidney fat mass. Additionally, we assessed differences in leptin concentrations between the two seasons, lactating and nonlactating females, and gestating and nongestating females. Leptin concentrations were similar between seasons but were lower in lactating and gestating females. We did not detect significant relationships between leptin and the body fat metrics, indicating that leptin may have limited value for estimating fat reserves in white-tailed deer.

Hard boundaries influence African wild dogs' diet and prey selection

Summary Human‐mediated changes in habitat structure may disturb predator–prey relationships. We investigated the influence of perimeter fences on the diet of a reintroduced population of African wild dogs Lycaon pictus Temminck 1820 in a 316 km2, fenced reserve in South Africa, by tracking radio‐collared individuals during hunting periods to determine dietary composition from observed kills. Nutritional status of impala Aepyceros melampus and kudu Tragelaphus strepsiceros prey, as measured by the percentage of femur marrow fat, was significantly lower than that of unselectively culled individuals. This supports the hypothesis that wild dog predation is at least partially compensatory. Fence‐impeded kills (those for which escape was deemed to be compromised by the fence) comprised 40·5% of kills (n = 316), and 54·1% of all edible biomass consumed. Compared with fence‐unimpeded kills, fence‐impeded kills comprised larger species (32·9 vs. 25·0 kg, W = 25667·0, P ≪ 0·001), older age classes for one prey category (female kudu: Fisher's exact test, P = 0·02, n = 65) and animals in better condition for adult impala males (Mann–Whitney, W = 111·0, P = 0·012, n = 28). Fence‐impeded kills also provided greater catch per unit hunting effort (27·3 vs. 12·2 kg km−1; χ2 = 7·89, P = 0·005), resulting in longer interkill intervals. Movement of the pack towards the fence at the start of each hunting period suggested a decision to exploit the advantage that fences conferred for capturing prey. Synthesis and applications. By enabling coursing predators to capture prey that would otherwise have escaped, fences may reduce the compensatory nature of predation, causing shifts in predator–prey dynamics that could influence the ability of small reserves to support such predators. The establishment of larger conservation areas to reduce perimeter‐to‐area ratios should be encouraged to limit the undesired effects of fences on predator–prey dynamics.

Physiological Condition of Female White-tailed Deer in a Nutrient-deficient Habitat Type

Abstract Physiological and morphological indices are useful for determining condition of Odocoileus virginianus (White-tailed Deer; hereafter deer) and are important for deer management. However, information about deer condition in nutrient-deficient habitat types is sparse. Pocosins have a low nutritional plane and are characterized by deep, acidic, peat soils with a dense shrub layer that provides little or no hard and soft mast. In July 2008 and March 2009, we collected a total of 60 female deer (30 from each period) from a 31,565-ha pocosin forest managed intensively for Pinus taeda (Loblolly Pine) in coastal North Carolina. We recorded whole weight, eviscerated weight, spleen and adrenal gland weights, and kidney fat index (KFI). Abomasal parasite counts (APC) and femur marrow fat index (MFI) were determined post-collection in the laboratory, and blood samples were analyzed for packed cell volume and standard serum chemistries. Serum chemistries were within expected ranges, with the exception of elev...

Evaluation of Stored Body Fat in Nuisance-Killed Japanese Black Bears (Ursus Thibetanus Japonicus)

We evaluated the stored body fat of Japanese black bears (Ursus thibetanus japonicus) killed as nuisances in Gifu and Fukushima prefectures, Japan, during 2005-2007. We employed femur marrow fat (FMF), modified kidney fat index (mKFI), and abdominal subcutaneous fat (ASF) as indices for quantitative evaluation. We examined the basic characteristics of these indices, such as seasonality, age and sex dependency, and the quantitative relationship among them. mKFI and ASF increased towards the beginning of the denning period (December), while FMF was relatively stable throughout the sampling period (July-December). In cubs, all indices showed significantly lower values than in the older age classes. There seemed to be a catabolizing order between FMF and mKFI, but not between mKFI and ASF. We also evaluated the yearly change in the indices, and discussed its relevance to the incidence of bear intrusion into human residential areas. Bears nuisance-killed in summer (July-September) 2006 had a significantly larger amount of stored body fat than those killed in summer 2007, although the number of nuisance kills was larger in 2006 than in 2007. This suggests that poor nutritional condition is not a direct cause of bear intrusion.

Increased Bone Marrow Fat in Anorexia Nervosa

Although women with anorexia nervosa (AN) have severe depletion of body fat, a paradoxical increase in bone marrow fat has been described. Recent data suggest that marrow fat measured by 1H-magnetic resonance spectroscopy (MRS) in combination with bone mineral density (BMD) may be more valuable than either parameter alone in detecting bone weakness. The objective of the study was to investigate the effect of AN on accumulation of marrow fat in spine and femur using 1H-MRS and the relationship between marrow fat, BMD, and body composition in subjects with AN and normal-weight controls. This was a cross-sectional study. The study was conducted at a referral center. Patients included 10 women with AN (29.8 +/- 7.6 yr) and 10 normal-weight age-matched women (29.2 +/- 5.2 yr). There were no interventions. Marrow fat content of the fourth lumbar vertebra and femur measured by 1H-MRS. BMD of spine and hip measured by dual-energy x-ray absorptiometry. Subjects with AN had higher marrow fat at the fourth lumbar vertebra and femur compared with controls (P = 0.004-0.01). There was an inverse correlation between marrow fat of L4 and femur and BMD of the spine and hip (r = -0.56 to -0.71, P = 0.01-0.0002) and body mass index and sc adipose tissue of the thigh (r = -0.49 to -0.71, P = 0.03-0.0007). There was an inverse correlation between femur marrow fat and sc and total abdominal adipose tissue (r = -0.53 to -0.67, P = 0.003-0.03). Women with AN have greater lumbar and femoral marrow fat than controls, and marrow fat correlates inversely with BMD. This paradoxical increase in marrow fat at a time when sc and visceral fat are markedly reduced raises important questions about functional consequences of this process.

Precision of Descriptors for Percent Marrow Fat Content for White-tailed Deer, &lt;em&gt;Odocoileus viriginianus&lt;/em&gt;

Based on 168 records of both verbal descriptors of White-tailed Deer (Odocoileus virginianus) femur-marrow fat and percentage of fat measured later, “gelatinous” served well to distinguish fat &lt; 46% from higher percentages. “Waxy” distinguished fat &gt; 56%.

Selectivity of wolf predation on red deer in the Bieszczady Mountains, Poland

A pattern of wolfCanis lupus Linnaeus, 1758 predation on red deerCervus elaphus Linnaeus, 1758 was studied in Bieszczady Mountains in 1991–2002. In total 324 remains of red deer > 4 months old, killed by wolves throughout the year, were found. The sex, age and bone marrow fat content of wolf kills were compared with the same characteristics within the free living red deer population. The overall contribution of calves killed by wolves (24%) in October-May was higher than in the population (17%), and decreased from autumn to spring. Adult males were more vulnerable to wolf predation than adult females: stags constituted 62% and hinds 38% of adult red deer killed by wolves, whereas in the population, the percentages were 37 and 63%, respectively. Stags killed by wolves were younger (\(\bar x = 4.1\) years old) than hinds (\(\bar x = 8.9\) years old). Wolves killed more > 8 years old hinds and < 5 years old stags than available in the population. In wolf kills, the average fat content in femur marrow was higher among hinds (84.9%) than stags (69.3%) and calves (66.1%). Only 8% of hinds had < 70% femur marrow fat content, whereas 40% of calves and 38% of stags had marrow fat values below that level. Marrow fat content showed seasonal variation and was the lowest in March among all sex-age classes. The monthly share of stags in all kills, and hinds in hind-calf part of the sample was negatively correlated with their monthly average bone marrow fat content, and monthly share of calves was positively correlated with monthly average bone marrow fat content of adults. The segregation of social units (hind-calf and stag groups), except during the rutting season, and the low fat reserves of males from midwinter until spring contribute to the high overall incidence of calves and adult males and the relatively low incidence of adult females among wolf kills.

Demographics and Condition of Coyotes in Illinois

Abstract The rapid growth of coyote (Canis latrans) populations in Illinois since 1980 prompted a need for current demographic data to be used in population models for management. From 1994 to 1997 we examined 977 coyotes harvested by hunters and trappers throughout the state and compiled data on age structure, sex ratios, reproductive rates and physical condition. Statewide, 55% of harvested coyotes were juveniles, 20% were yearlings and 25% adults. The sex ratio did not differ from unity among juveniles and yearlings, but was skewed towards males in the adult class. The number of harvested animals decreased by 45–60% between successive classes from 0.5 through 2.5 y old, then by 30–40% through 9.5 y old. Statewide, 57% of females bred and breeders averaged 4.9 placental scars. Males were larger than females, averaging 14.1 and 12.1 kg whole body mass, respectively. Kidney fat reserves were highest in juveniles and adult females and lowest in yearlings. Femur marrow fat was generally high and did not dif...

Canada Lynx Predation on White-tailed Deer

This note presents a documented incident of Canada lynx (Lynx canadensis) predation on white-tailed deer (Odocoileus virginianus). An adult male lynx killed a yearling male deer in poor condition (71.5% femur marrow fat) on 20 February 2003 in northern Maine. The chase from the point of attack to the deer carcass was 112 m. Snow depth was 47–78 cm and sinking depth of the deer was 12–38 cm, which is near the critical sinking depth and impedes deer mobility. This observation suggests that Canada lynx may opportunistically prey on deer.

Significant relationships between the serum leptin concentration and the conventional fat reserve indices in a wildlife species, Hokkaido sika deer (Cervus nippon yesoensis)

We assayed the serum leptin concentration and determined its correlation with the kidney fat mass (KFM), kidney fat index (KFI), and femur marrow fat (FMF) indices in 12 Hokkaido sika deer (Cervus nippon yesoensis Heude, 1884) collected in April, June, and October 2000. The KFM and KFI in April and June were both significantly lower than those in October. The leptin concentrations in April and June and in October were 1.222–1.521 ng mL–1 HE (Human Equivalent) units and 1.676–2.63 ng mL–1 HE, respectively, without overlapping. The relationships between the leptin concentration and the KFM, KFI, and FMF were all significant. Therefore, we conclude that the serum leptin concentration can be used as a new index for fat reserves in Hokkaido sika deer. However, reliable results could not be obtained from four samples collected in April and June when the deer were in a lower nutritional status. This may be due to the limited sensitivity of the antisera in the commercial multi-species leptin RIA kit used. For practical use in wildlife biology, species-specific leptin assays should be developed to eliminate this problem.

Age and condition of deer killed by coyotes in Nova Scotia

Coyote (Canis latrans) predation is a major source of mortality for white-tailed deer (Odocoileus virginianus) in many areas of northeastern North America. However, if coyotes primarily remove deer that would have died of other causes in the absence of predation (compensatory mortality), the impact of predation would be minimal regardless of the number of deer removed. We examined the carcasses of 102 white-tailed deer consumed by coyotes during winter in southwestern Nova Scotia (Queens County) and on Cape Breton Island from 1992 to 1997. Sixty-nine deer were victims of predation, five died of other natural causes, two were killed in coyote snares, two were killed on the road, two were shot and not recovered during the autumn hunting season, and one was shot and abandoned in early winter. The causes of death of the remaining 21 deer could not be determined. Fawns were overrepresented in the sample of coyote-killed deer on Cape Breton Island, but the age distribution of deer killed by coyotes in Queens County did not differ significantly from that of local road-killed deer. Femur marrow fat reserves of deer killed by coyotes appeared to be as good as or better than those of road-killed deer in the vicinity of each study area. During winter, coyotes often killed deer in situations where deer were disadvantaged either by deep snow or by poor footing on frozen lakes. This may help explain the general lack of selection of weaker animals. Our data are consistent with the idea that mortality due to coyote predation was largely additive to mortality due to other factors. However, manipulative experiments are needed to verify this conclusion.

Correlation Patterns of Marrow Fat in Rocky Mountain Elk Bones

Femur marrow fat is a useful predictor of ungulate condition when overall body condition is poor. Although predicting femur fat from other bones may be a viable option when femurs are unavailable, equations describing correlation patterns among various bones in Rocky Mountain elk (Cervus elaphus nelsonii) have not been reported. Using the dry weight method, we determined the fat content of femur, metatarsus, and mandible bones from predator- and vehicle-killed elk during winter. Metatarsus and mandible marrow fat levels were both significantly correlated to femur marrow fat, but the femur-metatarsus relationship was a better predictor of femur fat due to its stronger correlation (r2 = 0.93 vs. 0.74) and more linear relationship with femur fat values. The best model for predicting elk femur fat content based on Akaike's Information Criterion (AIC) model selection included both metatarsus and mandible fat but excluded age and sex. We suggest that the use of both bones is best for femur fat prediction in elk, but when used alone, the metatarsus is superior to the mandible. Because of its lower precision and weaker linearity, mandible fat may only be suitable for classifying animals into broader condition categories.

Assessing differential prey selection patterns between two sympatric large carnivores

Several conceptual models describing patterns of prey selection by predators have been proposed, but such models rarely have been tested empirically, particularly with terrestrial carnivores. We examined patterns of prey selection by sympatric wolves (Canis lupus) and cougars (Puma concolor) to determine i) if both predators selected disadvantaged prey disproportionately from the prey population, and ii) if the specific nature and intensity of prey selection differed according to disparity in hunting behavior between predator species. We documented prey characteristics and kill site attributes of predator kills during winters 1999–2001 in Idaho, and located 120 wolf‐killed and 98 cougar‐killed ungulates on our study site. Elk (Cervus elephus) were the primary prey for both predators, followed by mule deer (Odocoileus hemionus). Both predators preyed disproportionately on elk calves and old individuals; among mule deer, wolves appeared to select for fawns, whereas cougars killed primarily adults. Nutritional status of prey, as determined by percent femur marrow fat, was consistently poorer in wolf‐killed prey. We found that wolf kills occurred in habitat that was more reflective of the entire study area than cougar kills, suggesting that the coursing hunting behavior of wolves likely operated on a larger spatial scale than did the ambush hunting strategy of cougars. We concluded that the disparity in prey selection and hunting habitat between predators probably was a function of predator‐specific hunting behavior and capture success, where the longer prey chases and lower capture success of wolf packs mandated a stronger selection for disadvantaged prey. For cougars, prey selection seemed to be limited primarily by prey size, which could be a function of the solitary hunting behavior of this species and the risks associated with capturing prime‐aged prey.

Effect of domestic cattle on the condition of female white-tailed deer in southern pine-bluestem forests, USA

Effect of domestic cattle stocking on the nutritional condition of white-tailed deerOdocoileus virginianus (Zimmermann, 1780) was assessed using physiological indices of collected specimens. Three study areas were delineated in McCurtain County, Oklahoma (heavy cattle stocking), and Howard (moderate to light cattle stocking) and Pike (no cattle stocking) counties, Arkansas that were similar with respect to soils and vegetation but differed with respect to cattle stocking rate. Female white-tailed deer were collected from study areas in February and August 1987–1988 to assess nutritional condition. Deer collected from study areas exposed to cattle grazing in February had lower carcass weights, fat attributes (femur marrow and kidney fat), and reproductive rates (fetuses/doe) than deer that were not exposed to cattle grazing. In August, deer collected from the moderate cattle area had heavier eviscerated carcass weights, serum glucose, albumin, and albumin/globulin ratios than deer collected from the heavy cattle area. Results suggest that if cattle are removed from managed forests in winter, nutritional condition of deer would be improved because of reduced competition for food.

Winter Severity and Wolf Predation on a Formerly Wolf-Free Elk Herd

We studied wolf (Canis lupus) predation on elk (Cervus elaphus) in Yellowstone National Park from 17 March to 15 April 1997 (severe winter conditions) and from 2 to 31 March 1998 (mild winter conditions) 2-3 years after wolves were reintroduced to the park. Elk composed 91% of 117 kills. Data comparisons for 1997 versus 1998 were: hunting success rate, 26% versus 15%; kill rate, 17.1 kg/wolf/day versus 6.1; percent of kill consumed in first day 7 versus 86; percent femur marrow fat of adult kills, 27 versus 70; calf:adult ratios of kills, 2:33 versus 17:23; sex ratio of kills, 14M:19F versus 17M:6F; mean age of elk killed, males 6.1 years, females 15.2 versus males, 4.8, females 13.0. Winter severity influenced the wolf-elk relationship more than the naivete of the elk herd to predation by wolves.

A comparison of several indices for assessing body condition of Mongolian gazelle

Riney kidney fat index (RKFI), whole kidney fat index (WKFI), femur marrow fat index (FMFI), and tibia marrow fat index (TMFI) of 51 Mongolian gazelles (Procapra gutturosa), collected in Hulunbeier grassland, Inner Mongolian, China, were measured during spring, autumn and winter in 1997–98. These different indexes were compared for using them in assessing the body condition. There was a linear relationship (y=0.9444x−20.139; r=0.9454; p<0.01) between RKFI and KMFI. A linear relationship (y=0.9348x+1.1843; r=0.9875; P<0.01) between TMFI and FMFI also occurred for gazelles. There was a curvilinear relationship (y=31.44Ln(x)−44.403; r=0.8643; P<0.01) between FMFI and RKFI. FMFI remained high, while RKFI decreased to a certain extent. After most of the kidney fat was used, the femur marrow fat abruptly decreased. The results showed that the kidney fat index is more adequate for evaluating the population nutrition in good condition, but marrow fat index was more useful for assessing in poorer nutritional condition.

Kidney fat and marrow fat indices of the sika deer population at Mount Goyo, northern Japan

Fat deposits are effective indicators of the nutritional status of wild populations of ungulates. Three fat indices (kidney fat, femur marrow fat and mandible marrow fat) of sika deer (Cervus nippon) at Mount Goyo, northern Japan, were compared. The kidney fat index (KFI) was suitable for good and intermediate nutritional status, but could not precisely reflect poor conditions. Bone marrow fat indices (MFI) were not good indicators because samples with high MFI values did not distinguish between samples whose KFI values were different, and samples collected in non‐winter seasons did not cover the range of poor conditions. It is therefore recommended to use both the KFI and the femur‐MFI complementarily.