Influence of maternal nutritional status on prenatal growth in a Peruvian urban population

Anthropometric measurements were made on 4,952 mothers and their neonates from a Peruvian urban population. Based on age-specific percentiles, the mothers were separated into categories of short and tall stature, high and low fat, and high and low muscle. The study indicates that: (1) tall and short mothers characterized by similar subcutaneous fat and upper arm muscle area (whether high or low) had newborns with similar birth weight and recumbent length; (2) mothers characterized by high subcutaneous fat had heavier and fatter, but not longer, newborns than mothers with low subcutaneous fat; (3) mothers characterized by high upper arm muscle area had heavier, leaner and longer newborns than mothers with low upper arm muscle area; (4) mothers characterized by high muscle and high fat had heavier and longer newborns than mothers with high muscle and low fat; but (5) mothers characterized by high muscle and low fat had heavier and longer newborns than mothers with low muscle and high fat. Considering that subcutaneous fat and arm muscle area reflect calorie and protein reserves respectively, it is concluded that an increase in maternal calorie reserves results in increased infant fatness, but a lesser increase in linear growth. In contrast, an increase in maternal protein reserves does enhance both birth weight and prenatal linear growth.     

Seasonal variation in ornament expression,body size,energetic reserves,immune response,and survival in males of a territorial insect

Abstract 1. Seasonal variation in immune response has rarely been investigated in invertebrates and, therefore, we have studied this using territorial adult males of the damselfly, Hetaerina americana (Fabricius), in several generations, for a year and a half. 2. We investigated and related seasonal variation in red pigmented wing spot size (an ornamental trait) and body size to fat reserves using four immunity components – melanisation ability, phenoloxidase (PO) and nitric oxide (NO) activity, and haemolymph protein concentration – and survival ability after a bacterial immune challenge. 3. There was seasonal variation in spot expression, being more intense in the non‐winter months and less intense in winter months, and, to some extent, a similar pattern was found for NO. Although there was also variation in melanisation, PO activity, protein concentration and fat reserves, this was not consistently related to variation in spot size. Survival was lower in the winter than in non‐winter months. 4. Animals with larger spot and body size had greater values of melanisation, PO and NO activity, and protein concentration. The relation of spot and body size with fat reserves is still not clear. 5. Unlike other studies, ornament was not similarly correlated with all typical immune components (at best, mainly NO). 6. Similar to what occurs in vertebrates, survival is lower during the winter months. In the case of vertebrate studies, however, the same individual suffers these changes. In the American rubyspot, distinct cohorts demonstrated seasonal differences.     

Phenotypic and genetic parameters compared during repeated measures of longissimus muscle area and subcutaneous fat thickness in Nelore cattle

Real-time ultrasound is currently used for in vivo carcass evaluation of beef cattle. We estimated heritability and repeatability coefficients for ultrasound-measured carcass traits in Nelore cattle. We measured longissimus muscle area, backfat thickness, and rump fat thickness in male and female animals ranging in age from 10 to 26 months. The variance components were estimated by single-trait analysis using the derivative-free restricted maximum likelihood method, under an animal model. The complete data file included 3077 records of 1172 animals born between 2003 and 2008. Two analyses were performed using a repeatability model: a) all records of longissimus muscle area, backfat thickness, and rump fat thickness of animals aged 10 to 26 months, and b) considering two age periods (11 to 17 and 18 to 24 months). The heritability estimates ranged from 0.33 to 0.46 for longissimus muscle area, from 0.20 to 0.26 for backfat, and from 0.26 to 0.29 for rump fat, demonstrating that direct selection for these traits can provide genetic gain. The repeatability estimates were moderate, ranging from 0.42 to 0.73. The highest repeatability estimates were obtained for longissimus muscle area in both the first (0.70) and second (0.73) analyses. The repeatability estimates suggest that ultrasound measures are precise; higher precision was obtained for longissimus muscle area than for subcutaneous fat thickness. The latter could be obtained during periods of greater feed availability to increase precision.     

Body condition of a small passerine bird: ultrasonic assessment and significance in overwinter survival

The fitness benefits of intraspecific variation in physiological attributes have rarely been measured. Body condition, defined as the current status of metabolic reserves relative to likely demands, has often been implicated in subsequent survival, but has proved difficult to assess reliably in the live animal. A technique for assessing body condition, in terms of the main protein reserve of small birds, is presented. Pectoralis muscle thickness was measured in live birds using ultrasound reflection from the sternum. The relationship between the relative size of pectoralis muscles in autumn and the likelihood of overwinter survival in the dipper Cinclus cinclus was examined. The pectoralis reserves of male dippers surviving overwinter were significantly greater than those of birds which died or disappeared between late November and the breeding season in April. In contrast, variation in autumn condition of females was unrelated to overwinter survival.     

Electromyographic recordings of paraspinal muscles: Variations related to subcutaneous tissue thickness

The aim of this study was to assess the effect on EMG amplitude measures of variations in the thickness of underlying tissue between surface electrodes and the active muscle. 20 normal subjects with different amounts of subcutaneous tissue performed comparable constant force contractions for a 45-second period, during which paraspinal EMG recordings were taken. Three measures of subcutaneous tissue thickness were obtained from each subject: Body Mass Index, total body fat as calculated by Durnin's formula, and skinfold thickness at the recording sites. The results show that (i) the greater the thickness of subcutaneous tissue between the surface recording site and the contracting muscles, the lower the recorded electromyographic activity, and that (ii) up to 81.2% of the variance in the EMG measures can be explained by variation in the amount of subcutaneous tissue. These findings support the view that the absolute level of surface-recorded EMG cannot simply be taken at face value. The amplitude of the signal will be affected by, for example, the amount of body fat.Supported by the Physician's Services Inc. Foundation.     

Comparative energy allocation in two sympatric, closely related gobies: the black goby Gobius niger and the grass goby Zosterisessor ophiocephalus

Seasonal energy allocation of lipid reserves into different body tissues was analysed comparatively in two sympatric, closely related gobies: the grass goby Zosterisessor ophiocephalus and the black goby Gobius niger . Lipid reserves were measured in liver, muscle and ovary and compared between the two species within a given sex and seasonal period (reproductive v . non-reproductive). Furthermore, temporal patterns of lipid reserves were investigated in the two species in relation to gonado-somatic and liver-somatic indices, as well as the relationship between size and lipid content. Results showed that the grass goby allocated more lipid reserves in reproduction while the black goby accumulated more reserves in liver and muscle, at a given size, although the temporal patterns of lipid accumulation and depletion were basically similar. Results are discussed in the light of life-history theories, taking into account both adaptation and evolutionary constraints.     

The effect of unilateral isokinetic strength training on local adipose and muscle tissue morphology, thickness, and enzymes.

One-leg exercise of 5 weeks duration in 10 healthy middleaged women resulted in a significant increment of muscle force in the exercising leg and in a less, but at some angular velocities also significant, increase in the nonexercising leg. The thickness of subcutaneous tissue measured by ultrasound and skinfold caliper decreased, while muscle thickness increased in the exercising leg only. The increased thickness of muscle tissue was associated with an increase in the relative number and relative fiber area of type II fibers in the exercising leg. The mean fiber area of type IIB fibers increased significantly as well as the activity of lactate dehydrogenase and myokinase. The decrease of thickness of subcutaneous adipose tissue was not associated with a significant decrease in fat cell size and was probably due to geometrical factors secondary to hypertrophy of the underlying muscle. It is concluded that the relationship between lean and fat components of the human thigh is significantly influenced by changes in the activity of the thigh skeletal muscles, but a local dynamic strength training program can hardly be used for local emptying of the fat depot over the exercising muscles.     

Relationship between seasonal energy economy and thyroid activity in farm-raised raccoon dogs

1. The levels of thyroid hormones (T3, T4), total lipids and urea in blood serum of adult farmed raccoon dogs (Nyctereutes procyonoides Gray 1834) were monitored year-round, and compared with seasonal changes in body weight and feed consumption during intense, maintenance and restricted fasting feeding. 2. Thyroid hormone levels tended to be low during winter whereas during the rest of the year no marked seasonal differences were observed. That thyroid hormone levels were influenced by altering feed intake suggests the hypothesis that the winter hypothyroidism observed was a result of a decreased level of voluntary feed intake. 3. The colder the temperature was during winter, the less the animals consumed the feed supplied. 4. Neither season nor feed intake level affected serum levels of total lipids or urea. 5. Marked seasonal changes in body weight of the animals were found. From maximum values occurring in early winter their body weight generally dropped about 30% reaching the minimum values in mid-summer. This marked seasonal change was mainly the result of changes in subcutaneous fat reserves.     

Validating Predictive Models of Nutritional Condition for Mule Deer

Abstract: We developed new, and validated existing, indices of nutritional condition for live and dead mule deer (Odocoileus hemionus). Live animal indices included a body condition score (BCS), thickness of subcutaneous fat and selected muscles using ultrasonography, and body mass. Dead animal indices included femur, metatarsal, and mandible marrow fat, 3 kidney fat indices, and 2 carcass scoring methods. We used 21 female deer and 4 castrates (1-11 yr old) varying widely in nutritional condition (2-28% ingesta-free body fat). Deer were euthanized and homogenized for chemical analysis of fat, protein, water, and ash content. Estimates of fat and gross energy (GE) were regressed against each condition indicator using regression. Subcutaneous fat thickness, a rump BCS, and rLIVINDEX (an arithmetic combination of subcutaneous fat thickness and the rump BCS) were most related to condition for live animals (r² ≥ 0.87, P < 0.001) whereas the Kistner score and kidney fat were most related to fat and GE for dead animals (r² ≥ 0.77, P < 0.001). We also evaluated range of usefulness and sensitivity to small changes in body condition for all models. In general, indices with moderate or highly curvilinear statistical relations to body fat or those based on only one fat depot or a small number of ranking scores will have limitations in their use. Our results identify robust tools for a variety of research and monitoring designs useful for evaluating nutrition's effect on mule deer populations.     

Seasonal variations in the gonad size and the protein and water content of cod, Gadus morhua (L.), muscle from Northern Norway

Water and protein contents of muscle and gonad index of sexually mature and immature cod of the same size were studied throughout a one-year cycle. In mature cod, the gonad was found to increase isometrically with fish weight suggesting that the relative energy demand for gonadal growth is independent of fish size. Spawning took place in late March or early April. Similar seasonal variations of water and protein contents of the muscle occurred in both mature and immature cod. In December to February, the protein content reached a maximum and water content a minimum, and in March to April, protein content was low, whereas the water content of the muscle was at a maximum. Since mature and immature cod showed the same variations in body composition, it is suggested that little of the seasonal variations of mature cod can be explained by reproductive processes.     

Variation in body condition of breeding Savi’s Warblers Locustella luscinioides: the reproductive stress and flight adaptation hypothesis revisited

Current theory suggests that mass change in adult birds while breeding may be adaptive (to reduce wing-loading during nestling feeding) or result from physiological stress. To test which might be more important in determining mass loss in breeding Savi’s Warblers (Locustella luscinioides), we used a new approach in which the variation in four indices of body condition was described: weight, fat score, muscle score and lean weight (i.e. excluding fat and muscle). We expected weight variations to be adaptive if they involved changes in fat and lean weight, whereas physiological stress should influence the muscle score to a greater extent. As in other species, females showed a greater variation in weight, and carried more fat, than males during the breeding cycle. During incubation, females had greater weight and fat score than males. The weight remained constant and lean weight declined in both sexes, whereas females increased in muscle, which probably reflects the regression of the reproductive organs. During the nestling stage, both sexes declined significantly in all four indices of condition, showing evidence of physiological stress. However, the greater decline in weight in females than in males is consistent with the flight-adaptation hypothesis, as are the cyclic changes in lean weight associated with the various nesting attempts. The fact that both sexes declined significantly in weight, muscle and lean weight with an increasing number of nesting attempts, but not in fat, which was recovered after each nestling period, also indicates that both reproductive stress and adaptive changes occur during breeding. When the whole breeding season was considered, females showed a greater decline in muscle than males, which we interpret to be evidence for a greater reproductive stress in females. We suggest that the small breast muscle size and depleted protein reserves at the end of the breeding period might influence future survival through impaired flight ability and a compromised post-breeding moult.     

Estimation of genetic parameters for growth,carcass and overfeeding traits in a white geese strain

In an experimental strain of white plumage geese created in 1989, two experiments were carried out from 1993 to 1995 in order to estimate genetic parameters for growth, and carcass composition traits in non-overfed animals, and genetic parameters for growth and fatty liver formation in overfed animals. Four hundred and thirty-one non-overfed animals were bred and slaughtered at 11 weeks of age; they were measured for forearm length, keel bone length, chest circumference and breast depth before and after slaughtering. The carcasses were partly dissected in order weigh breast, breast muscle and skin + fat, and abdominal fat. Four hundred and seventy-seven overfed animals were slaughtered at 20 weeks of age; they were measured for "paletot" (breast meat, bone and meat from wings, bone and meat from thigh and legs) weight and liver weight. In these two experiments, the weights had moderate to high heritability values. Breast depth measured on live animals showed a low heritability value. In overfed animals, liver weight showed a high heritability value. Liver weight could be increased by selection without a great effect on "paletot" weight. Thus, obtaining a white plumage geese strain for fatty liver production by selection would be difficult because only 20% of overfed animals had fatty liver. The results did not allow to conclude on the influence of selection on liver weight on carcass traits such as muscle or fatty tissue weight.     

Seasonal changes in the biochemical composition of the freshwater murrel,Ophicephalus punctatus Bloch

Summary Seasonal variations in various biochemical constituents in the tissues of Ophicephalus punctatus showed that. the fat content in the muscle was highest during November–January and lowest during June–October. Liver contained more fat than the muscle and its seasonal cycle was marked by two well defined peaks. Changes in the ovarian fat were also well defined seasonally. The moisture content in all the tissues varied inversely with the fat. Protein values in different tissues did not show as much fluctuations as fat. In muscle, protein remained high throughout the year except in January. In liver and gonads very low protein values were recorded during the winter months. Seasonal changes in the ash content were not very well marked in any of the three tissues.The seasonal variations in all the biochemical constituents seem related to the feeding intensity of the fish and the maturation of its gonads. Maximum and minimum values of fat fell in accordance with the high and low food intake. In the pre-spawning phase, more fat was stored in the muscle at first but subsequently the fat was mobilized in the liver and finally in the gonads. Peak ripeness was associated with an accumulation of greater protein and fat in the gonads (ovaries). During the spawning months the various constituents were depleted and the post-spawning phase of the fish was marked by minimal values of most of the biochemical constituents, excepting moisture and ash.     

Body condition changes of sand martins (Riparia riparia) during breeding, and a comparison with fledgling condition

The body condition of adult sand martins during the breeding season and a sample of fledglings was investigated by carcass analysis and by examination of live birds in the field. Fat scoring of live individuals was a reliable predictor of an individual's lipid content in most instances. Body mass changes during breeding were related to changes in the size of birds' lipid reserves, pectoral muscle mass, body water, and to development of the reproductive system. In both males and females, reserve lipid declined between the onset of breeding and nestling rearing. Pre-breeding males had significantly greater pectoral muscle masses than did nestling rearing females. The potential significance of protein in pectoral muscles as an energy reserve during breeding was small compared with lipid reserves. By comparing potential energy reserves in body lipid and protein with daily energy expenditure, it was calculated that neither incubating nor nestling rearing adults could survive a day of normal activity without feeding. The selective premium on adults optimizing their use of time and energy for self-maintenance behaviour during breeding is therefore likely to be great.     

Seasonal variation and food deprivation in common vampire bats (Chiroptera: Phyllostomidae).

The aim of this study was to investigate the effects of seasonal variation and fasting on fat reserves of the common vampire bat Desmodus rotundus. Plasma free fatty acids (FFA), along with lipid content of the liver and muscles, and fatty acids from the carcass were obtained from bats fed bovine blood and from whom food was subsequently withheld for 24 and 48 h. Animals were caught during both dry and rainy seasons. In general, fat tissue stores were not significantly influenced by seasonal variation. Lipid content of liver, muscles, and carcass decreased during some food deprivation periods, although the concomitant increase expected in plasma FFA was not observed. Lipid metabolism is hypothesized as being continued by the tissues themselves. In addition, free access to food sources (e.g., domestic livestock) throughout the year is believed to contribute to the low seasonal variations in fat reserves observed in the common vampire bat.     

Fatty Acid Composition of Muscle,Adipose Tissue and Liver from Muskoxen (Ovibos moschatus) Living in West Greenland

Information about lipid content and fatty acid (FA) composition of muskoxen (Ovibos moschatos) edible tissues is very limited in comparison to other meat sources. Thus, this work aims to present the first in-depth characterization of the FA profile of meat, subcutaneous adipose tissue and liver of muskoxen living in West Greenland. Furthermore, we aim to evaluate the effect of sex in the FA composition of these edible tissues. Samples from muscle (Longissimus dorsi), subcutaneous adipose tissue and liver were collected from female and male muskoxen, which were delivered at the butchery in Kangerlussuaq (West Greenland) during the winter hunting season. The lipid content of muscle, adipose tissue and liver averaged 284, 846 and 173 mg/g of dry tissue, respectively. This large lipid contents confirms that in late winter, when forage availability is scarce, muskoxen from West Greenland still have high fat reserves, demonstrating that they are well adapted to seasonal feed restriction. A detailed characterization of FA and dimethylacetal composition of muskoxen muscle, subcutaneous adipose tissue and liver showed that there are little differences on FA composition between sexes. Nevertheless, the 18:1cis-9 was the most abundant FA in muscle and adipose tissue, reaching 43% of total FA in muscle. The high content of 18:1cis-9 suggests that it can be selectively stored in muskoxen tissues. Regarding the nutritional composition of muskoxen edible tissues, they are not a good source of polyunsaturated FA; however, they may contribute to a higher fat intake. Information about the FA composition of muskoxen meat and liver is scarce, so this work can contribute to the characterization of the nutritional fat properties of muskoxen edible tissues and can be also useful to update food composition databases.     

Response of the haematocrit to body condition changes in Northern Bald Ibis Geronticus eremita

We study the usefulness of the haematocrit as a predictor of body condition in birds, using a captive population of the endangered species Northern Bald Ibis (Geronticus eremita). This population is 14% of the worldwide captive population, which is far greater than the known free-living population. The haematocrit, body mass and body condition index responded in the same sense to two different nutritional periods, and there was a statistically significant relationship between changes in condition index and haematocrit of individual birds between the two periods. We discuss the relationship of these parameters with subcutaneous fat and muscle mass, and analyse the individuals' nutritional status in each of the periods studied. The conclusion was that the haematocrit is sensitive to variations in body condition since it responds to mass-loss processes corresponding to phases of mobilization of fat reserves, a situation prior to the mobilization of muscle proteins when there is a manifest deterioration of the individual's aspect.     

Tissue deposition rates in relation to muscle fibre and fat cell characteristics in lean female pigs (Sus scrofa) following treatment with porcine growth hormone (pGH)

Two experiments were conducted to examine the effect of porcine growth hormone (pGH) on performance, carcase composition, muscle and fat deposition rates, muscle fibre characteristics, and fat cell volume in pigs. In the first experiment, ten pairs of littermates were treated with vehicle (saline buffer) or 80 μg pGH per kg live weight per day for 42 days starting at 50 kg live weight. In the second experiment, twelve pairs of littermates were untreated or treated with 3 mg pGH per day from approximately 56 kg live weight to slaughter at approximately 103 kg live weight. All pigs were fed ad libitum. In Experiments 1 and 2, respectively, feed intake decreased (10 and 11%) and the feed/gain ratio improved (8 and 13%), while daily gain was unaltered. There was an increase in deposition rates of muscle (11 and 22%), skin (27 and 23%), and bone (15% in both), and a decrease in deposition rates of intermuscular (48 and 24%) and subcutaneous (82 and 50%) fat. This resulted in a change in carcase composition towards more muscle (5 and 9%), bone (6 and 4%), and skin (18 and 12%), and less intermuscular (30 and 16%) and subcutaneous fat (51 and 32%). The increased muscle mass was due to enhanced hypertrophy of all muscle fibre types, while pGH did not affect the frequency of the different muscle fibre types. The reduction in subcutaneous fat was reflected in a similar reduction in fat cell volume. In contrast to the majority of pigs used in pGH experiments, the genotype used in the present experiments did not respond with respect to daily gain following pGH treatment. Furthermore, the increase in muscle deposition was rather low compared to results reported in pigs of other genotypes. These data together with published data on the cross-sectional area of muscle fibres indicate that genotypes with relatively large muscle fibres are less responsive to pGH treatment than genotypes with relatively small muscle fibres.     

Smoking in pregnancy: associations with skinfold thickness,maternal weight gain,and fetal size at birth.

Skinfold thickness is an index of subcutaneous fat, and certain maternal conditions during pregnancy affect the skinfold thicknesses of the baby. A study was performed to investigate the effect of smoking on skinfold thickness, maternal weight gain, and fetal size at birth. A total of 452 mothers with normal singleton pregnancies were groups as: non-smokers, light-to-moderate smokers, or heavy smokers. Maternal age, height, parity, and duration of pregnancy were similar in the three groups. Heavy smokers gained significantly less weight than non-smokers, but there was no significant difference in skinfold thickness. Babies born to smokers had lower birth weights and smaller head circumferences and were shorter than those born to non-smokers, but skinfold thicknesses were similar. The presence of a normal layer of subcutaneous fat in babies whose mothers smoked suggests that fetal growth retardation is not caused by nutritional deficiencies.