Inclusion Of Fat Research Articles

The impact of dietary fat withdrawal on carcass iodine value, belly characteristics, and changes in body fat over time1

The inclusion of unsaturated fats in pig diets has raised issues related to pork carcass fat quality. The objective of this experiment was to understand how withdrawal from the diet of unsaturated dietary fat before slaughter impacts the composition of jowl fat during the growth cycle and at market. Fifty individually housed pigs (PIC 337 × C22/29; initial BW = 59.3 ± 0.55 kg) were allotted based on sex and initial BW to 10 treatments for an 82-d experiment as follows: 3 dietary fat withdrawal times before slaughter (21, 42, or 63 d) by 3 dietary fat unsaturation loads (DFUL), which includea high intake of unsaturated fatty acids supplied through an inclusion of 5% corn oil (HIGH), a high intake of a mixture of saturated and unsaturated fatty acids supplied through an inclusion of 5% animal-vegetable blend (MED), and a moderate intake of unsaturated fatty acids supplied through an inclusion of 2.5% corn oil (LOW). Pigs were weighed and jowl adipose samples were collected on d 0, 21, 42, and 63 and at harvest on d 82. Data were analyzed using PROC MIXED with treatment and sex as fixed effects. At market (d 82), increasing the withdrawal of dietary fat further away from market increased 18:1 (P = 0.045) and tended to increase 14:0 concentrations (P = 0.054). It also significantly decreased 18:2 (P < 0.001) and tended to decrease 18:3 concentrations (P = 0.081). A HIGH DFUL resulted in the greatest 18:2 concentrations in jowl fat followed by LOW; MED resulted in the lowest 18:2 levels (P < 0.001). Dietary fat withdrawal before market significantly reduced carcass iodine value (IV) measured at d 82 (P = 0.006). In conclusion, elevated 18:2 intake makes lowering carcass IV in the depot fat very difficult and may take as long as 61 d. The withdrawal of unsaturated dietary fat apparently altered the fat depot to be more reflective of fat synthesized de novo, resulting in a more saturated depot fat. Importantly, this alteration of deposited fat composition did not translate into improved belly firmness, depth, weight, or fat color.

Cooking loss, cooking time, patty shrink and color of nilgai antelope patties with beef or pork fat inclusion

Cooking loss, cooking time, patty shrink and color of nilgai antelope patties with beef or pork fat inclusion

Impact of particle size, thermal processing, fat inclusion, and moisture addition on starch gelatinization of broiler feeds

The present study evaluated the effect of feed particle size, thermal processing different levels of fat inclusion and of moisture addition on the amount of gelatinized starch in a corn-soybean broiler diet. The different processing factors were combined in a 2 x 4 x 4 x 2 factorial arrangement in a three randomized block design consisting of three production series: two particle sizes (coarse: 1041 microns and medium: 743 microns), four fat inclusion levels at the mixer (15, 25, 35, and 45 g/kg of feed), four moisture addition levels in the conditioner (0, 7, 14, and 21g/kg of feed), and two thermal processing treatments (conditioning-pelleting or conditioning-expanding-pelleting) which resulted in 64 different processed feeds. For the determination of the amount of gelatinized starch one feed sample was collected per treatment in each of three production series, totaling three replicates/treatment. Data were transformed using a variation of Box-Cox transformation in order to fit normal distribution (p>0.05). Adding moisture up to 21g/kg of feed in the conditioner linearly increased the amount of gelatinized starch (p<0.05). The conditioner-expander-pelleting treatment of the diets (at 110°C) increased (p<0.05) the degree of starch gelatinization from 32.0 to 35.3 % compared with the conditioner-pelleting treatment (at 80-82°C). The gelatinized starch content increased from 30.2 to 37.2% in the feed (p<0.05) as the particle size increased from medium to coarse. Fat inclusion had a quadratic effect (p<0.05) on starch gelatinization. The degree of starch gelatinization was significantly reduced with fat inclusion levels higher than 35 g/kg of diet. The factors evaluated in this study resulted in interactions and significant effects on degree of starch gelatinization.

Energy utilization of by-products from the soybean oil industry by broiler chickens: acidulated soapstock, lecithin, glycerol and their mixture

Acidulated soy soapstock (ASS) and lecithin (LEC) are by-products from processing soy oil (SO) for human consumption, whereas glycerol (GLY) can be obtained through the transesterification of vegetable oils during the production of biodiesel. These are valuable by-products for poultry feeds that have been underutilized in many parts of the world. One study was conducted to estimate the AMEn of ASS, LEC, GLY as well as of their mixture (MIX: 85% ASS, 5% LEC and 10% GLY). Two hundred and sixty Cobb 500 female broilers of 20 days of age were housed in steel wire battery cages in a controlled temperature room for broilers. A completely randomized (energy sources x fat inclusion level) factorial design was applied, with 4 replicates of three birds per treatment. Birds were fed a corn-soybean meal control diet without supplemental fat or with the addition of 2, 4, or 6 % of the four energy sources. Total excreta collection was performed from 26 to 28 days. The AMEn values of by-products were calculated using regression analysis as well as by the difference method. The average AMEn values calculated by regression analysis were: 9,232, 7,502, 5,447 and 8,404, whereas results with the difference method were: 7,951, 6,579, 3,979 and 8,101 kcal/kg for, in both cases for ASS, LEC, GLY and MIX, respectively. It is concluded that these energy sources can be for broilers and that there are significant differences between the methods used to estimate AMEn of fats.

Impact of dietary fat source and concentration and daily fatty acid intake on the composition of carcass fat and iodine value sampled in three regions of the pork carcass.

The increased inclusion of unsaturated fats in pig diets has raised issues related to pork carcass fat quality. The objective of this experiment was to more precisely measure how differing levels of daily fatty acid intake alters the fatty acid composition in 3 different fat depots. A total of 42 gilts and 21 barrows (PIC 337×C22/29) with an average initial weight of 77.80±0.38 kg were allotted randomly based on sex and BW to 7 treatments: 3 and 6% of each of tallow (TAL; iodine value [IV]=41.9), choice white grease (CWG; IV=66.5), or corn oil (CO; IV=123.1) and a control (CNTR) corn-soybean meal-based diet with no added fat. Pigs were individually housed to allow accurate measurement of individual feed intake, in particular, daily dietary fatty acid and energy intake. Fat samples were collected from the jowl, belly, and loin at slaughter. Diet and carcass fat samples were analyzed for IV. Belly weights were recorded at slaughter along with a subjective belly firmness score (1=firmest to 3=least firm). Carcass lipid IV was increased (P<0.001) by increasing the degree of unsaturation of the dietary fat source (66.8, 70.3, and 76.3 for TAL, CWG, and CO, respectively). Carcass lipid IV for TAL and CWG was not affected (P>0.05) by inclusion levels; however, carcass lipid IV was greater (P<0.001) in pigs fed 6 than 3% CO (80.0 vs. 72.6), and carcasses of gilts had greater IV (P<0.001) than carcasses of barrows (71.5 vs. 69.1). Increasing the level of TAL and CO but not CWG from 3 to 6% decreased the apparent total tract digestibility of GE, resulting in a source×level interaction (P<0.05). Dietary fat source had no effect (P≥0.66) on apparent total tract digestibility of either DM or GE, but feeding 6% dietary fat increased G:F (P=0.006) over pigs fed 3% fat (0.358 vs. 0.337). Of all the fatty acids measured, only linoleic acid intake presented a reasonable coefficient of determination (R2=0.61). Overall, IV product (IVP) was approximately equal to linoleic acid intake as a predictor of carcass IV (R2=0.93 vs. R2=0.94). When inclusion of dietary fat and PUFA intake increased, IVP placed more emphasis on the dietary fat inclusion level rather than the dietary fat composition. Linoleic acid intake corrected the overemphasis placed on dietary fat inclusion by IVP. To conclude, linoleic acid intake showed a strong relationship with carcass IV and can be used as a predictor.

Desempeño de cabritos recibiendo dietas liquidas con diferentes niveles de grasa durante la etapa de amamantamiento

Los objetivos del estudio fueron evaluar diferentes niveles de inclusión de grasa de leche de cabra en la alimentación de cabritos durante la fase de amamantamiento (37 días de vida) y estudiar su efecto en el desempeño, a través del consumo y digestibilidad de los nutrientes. Se utilizaron 60 cabritos machos de las razas Saanen y Alpina, con inclusión de cinco niveles de grasa en la dieta (2,42; 3,44; 4,43; 6,56; y 8,21 %), utilizando un diseño completamente al azar con 12 repeticiones. A partir del séptimo día de vida cada unidad experimental recibió 1,5 L/leche/día dividida en dos raciones 08:00 -15:00 horas; el consumo individual de materia seca (CMS) fue obtenido por la diferencia entre la cantidad ofrecida y las sobras. Se determinó la digestibilidad de los nutrientes a través del método directo por colecta total de heces. Las muestras fueron posteriormente sometidas a análisis químico. El CMS fue influenciado (p&lt;0,001) por el contenido de grasa en la dieta, presentando comportamiento cuadrático; efecto observado en los demás nutrientes. Igualmente, el coeficiente de digestibilidad del extracto etéreo (CDEE) y de los carbohidratos no fibrosos (CDCNF) se vieron afectados (p=0,015; p&lt;0,001 respectivamente), observándose comportamiento linear y cuadrático respectivamente. Aumentar la concentración energética de la dieta hasta el nivel 6,56 % de inclusion de grasa lactea, aumenta el CMS, CDCNF y CDEE, sin embargo, este incremento no causa mejoras en la ganancia de peso durante esta fase, no justificando la adición de crema a la leche.

Influence of tallow and calcium concentrations on the performance and energy and nutrient utilization in broiler starters

The influence of tallow and Ca concentrations on the performance, apparent ileal digestibility, and total tract retention of N, Ca, P, and AME in broiler starter diets fed corn-soy-based diets was examined. The experimental design was a 3 × 3 factorial arrangement of treatments evaluating 3 inclusion levels of tallow (0, 40, and 80 g/kg) and 3 dietary concentrations of Ca (7, 10, and 13 g/kg). Nine treatment diets were formulated to meet the requirements for major nutrients for broiler starters, except for AME and Ca concentrations. The results showed that increasing tallow inclusion increased (P < 0.001) the weight gain and lowered (P < 0.001) the feed to gain. Increasing dietary Ca concentrations decreased (P < 0.001) the weight gain. Birds fed diets containing 7 g/kg of Ca had similar (P > 0.05) feed to gain to 10 g/kg of Ca but lower (P < 0.05) than that of 13 g/kg of Ca. In diets with no tallow, increasing Ca concentrations decreased (P < 0.05) feed intake, whereas diets with 40 and 80 g/kg of tallow containing 13 g/kg of Ca showed lower (P < 0.05) feed intake than those of 7 and 10 g/kg of Ca. Diets supplemented with 40 and 80 g/kg of tallow containing 7 g/kg of Ca showed the lowest (P < 0.05) excreta soap content. Total tract retention of fat was higher (P < 0.001) in diets with 40 g/kg of tallow compared with those with 0 and 80 g/kg of tallow. Birds fed diets containing 7 g/kg of Ca had similar (P > 0.05) fat retention to that of 10 g/kg of Ca, but higher (P < 0.05) than that of 13 g/kg of Ca. Calcium retention decreased (P < 0.001) with increasing Ca concentrations. Diets containing 13 g/kg of Ca had the lowest (P < 0.01) P retention. Diets with no inclusion of tallow containing 7 g/kg of Ca had higher (P < 0.05) N retention than that of 13 g/kg of Ca, but similar to 10 g/kg of Ca, whereas in 40 g/kg of tallow diets, 7 g/kg of Ca had the highest (P < 0.05) N retention. Increasing fat inclusion increased (P < 0.001) the soap content in ileal digesta. Diets with 40 g/kg of tallow had the highest ileal digestibility of fat (P < 0.001) and N (P < 0.01). Increasing inclusion of fat decreased (P < 0.001) ileal Ca digestibility. Diets containing 7 g/kg of Ca showed the highest ileal digestibility of fat (P < 0.01), N (P < 0.01), and P (P < 0.001). Birds fed diets containing 13 g/kg of Ca had higher ileal digestibility of Ca (P < 0.001) than those fed 7 and 10 g/kg of Ca diets. Overall, present data showed that the total tract retention and ileal digestibility of fat were higher with supplementation of 40 g/kg of tallow compared with those of 0 and 80 g/kg of tallow. High dietary Ca concentrations adversely affected the performance and the utilization of energy, N, Ca, and P in broiler starters.

Intravenous glucagon like peptide-1 infusion does not affect dry matter intake or hypothalamic mRNA expression of neuropeptide Y, agouti related peptide and proopiomelatnocortin in wethers

Relling, A. E., Loerch, S. C. and Reynolds, C. K. 2014. Intravenous glucagon like peptide-1 infusion does not affect dry matter intake or hypothalamic mRNA expression of neuropeptide Y, agouti related peptide and proopiomelanocortin in wethers. Can. J. Anim. Sci. 94: 357–362. The objectives of the present study were to determine the effects of jugular vein infusions of glucagon like peptide-1 (GLP-1) and dietary fat inclusion on dry matter intake, nutrient digestibility and hypothalamic mRNA concentration of neuropeptide Y, agouti related peptide, and proopiomelanocortin in growing sheep. Thirty-six wethers were used (40.7±3.3 kg BW). Treatments were a control diet (n=11), dietary addition (6% of dry matter) of Ca salts of palm oil fatty acids (n=12), or 6-d jugular vein infusions of 0.155 µg kg−1 body weight/day of GLP-1 (n=11). Hormone concentrations were measured in jugular vein plasma from samples taken on days 1, 4 and 6. On day 7, the wethers were slaughtered for hypothalamus collection to measure mRNA concentration. The dietary addition of 6% of Ca salts of palm oil increased plasma GLP-1 concentration (P&lt;0.01) and decreased dry matter intake on day 1, but not on day 6 (time×treatment interaction, P&lt;0.05). The infusion of GLP-1 did not change dry matter intake (P&gt;0.20), but increased neutral detergent fibre digestibility (P&lt;0.01). In conclusion, glucagon like peptide-1 infusion or feeding fat did not decrease dry matter intake or affect hypothalamic neuropeptide mRNA concentrations of sheep.

Amino acid digestibility in low-fat distillers dried grains with solubles fed to growing pigs.

The objective of this experiment was to determine the standardized ileal digestibility (SID) of amino acids (AA) in 3 sources of distillers dried grains with solubles (DDGS) with different concentrations of fat. Twelve growing barrows (initial body weight: 76.1 6.2 kg) were randomly allotted to a replicated 6 × 4 Youden square design with 6 diets and 4 periods. The fat content of the 3 sources of DDGS were 11.5, 7.5, and 6.9% respectively. Diets contained 60% DDGS and fat concentration of the diets were 7.5, 5.2, and 5.2%, respectively. Two additional diets containing the 2 sources of DDGS with 7.5 and 6.9% fat were also formulated, and corn oil was added to these diets to increase the concentration of fat in the diets to levels that were calculated to be similar to the diet containing conventional DDGS with 11.5% fat. A N-free diet was also formulated to calculate endogenous losses of crude protein (CP) and AA from the pigs. Pigs were fed experimental diets during four 7-d periods. The first 5 d of each period were an adaptation period and ileal digesta were collected on d 6 and 7 of each period. The apparent ileal digestibililty (AID) and SID of CP and all indispensable AA, except AID Pro and SID of Trp, were greater (P < 0.01) in conventional DDGS than in the 2 sources of DDGS with reduced fat. Adding oil to the diets containing the 2 sources of DDGS with reduced fat did not consistently increase SID of AA. In conclusion, conventional DDGS has greater SID values for most AA compared with DDGS that contains less fat and inclusion of additional oil to diets containing low-fat DDGS does not increase AID or SID of AA. The lower AA digestibility in low-fat DDGS could not be overcome by the inclusion of additional fat to the diets.

The effects of organic selenium on performance and oxidative level in rainbow trout (&lt;i&gt;Oncorhynchus mykiss&lt;/i&gt;, Walbaum, 1792) fed a high-fat diet

The main objective of this study was to determine the impact of dietary fat on the organic selenium requirement of rainbow trout. There were two variables in this study. The first was organic selenium that was sup - plemented at 0.1, 0.15 and 0.2 mg · kg -1 . The second variable was the fat inclusion level as low-fat (15%) and high-fat (30%) diets. This led to formula- tion of six experimental diets according to a 3 × 2 factorial design. Juvenile rainbow trout with an initial weight of 6.99 ± 0.9 g were assigned to 18 tanks with 25 fish each, with three replicates for each diet. The results showed that the tissue oxidation rate increased with increased dietary fat content. The initial and final fish stocking densities were 0.58 and 2.08 kg · m -3 , respec- tively. Addition of dietary selenium increased glutathione peroxidase activity. Final weight and specific growth rate were not influenced by the fat level of the diets. On the high-fat diet, selenium improved the feed conversion ratio by depression of the oxidation rate. The dietary selenium requirement depended on the dietary fat content and 0.15 mg · kg -1 was found to be necessary for the high-fat diet. A reduction in oxidation level by inclusion of selenium into the diets was observed and was associated with the higher activity of glutathione peroxidase.

Effect of cassava bioethanol by-product and crude palm oil in Brahman x Thai native yearling heifer cattle diets: I. Nutrient digestibility and growth performance

The effects of cassava bioethanol by-product (CEP) and crude palm oil (CPO) on feed intake, nutrient digestibility, and growth performance of yearling heifers were investigated in a 150-day feeding trial. Eighteen, crossbred heifers (Brahman x Thai native) were randomly allotted according to 2 × 3 factorial arrangement. Low or high levels of CEP (15 or 30% of concentrate, LCEP, or HCEP) were basal treatments and 0, 2, and 4% CPO were daily top-dressed. Concentrate was supplemented at 1.75% of body weight (BW) and rice straw offered ad libitum. CEP level had no significance on feed intake. CPO increased roughage intake, concentrate intake, and total feed intake when expressed as %BW/d (P < 0.01) and as metabolic BW (kg(0.75)/d, P < 0.05). Intakes of dry matter (DM), organic matter (OM), and crude protein (CP) were similar (P > 0.05). Intake of fat increased with higher levels of CPO (P < 0.001). The DM, OM, CP, and EE digestibility of cattle-fed HCEP was lower than LCEP, but adding 4% CPO increased digestibility. Growth performance was similar for all diets (P > 0.05). We concluded that CEP can be used up to 30% in the diet, with or without additional fat inclusion.

A meta-analysis of the effect of dietary fat on enteric methane production, digestibility and rumen fermentation in sheep, and a comparison of these responses between cattle and sheep

The objective of this study was to investigate the effect of dietary fat supplementation on methane production, digestibility and rumen fermentation in sheep by means of a meta-analysis, and subsequently to compare the results with response in cattle. A dataset was constructed compiling data from ten published publications containing 41 dietary treatments and 259 observations on sheep. Fat supplementation decreased methane production (expressed as g/day, g/kg dry matter (DM) intake, g/kg digestible DM intake, % of gross energy intake) linearly (P<0.05; R2=0.49 to 0.78). Inclusion of fat did not (P=0.21) affect DM intake. However, digestibilities of DM (P=0.04; R2=0.24) and neutral detergent fiber (P=0.09; R2=0.16) reduced linearly with increasing fat concentrations. Conversely, fat digestibility increased quadratically (P=0.03; R2=0.65) with increasing fat contents. Total volatile fatty acids and acetate percentage in rumen fluid were not altered (P>0.10) by dietary fat supplementation. Percentage of propionate increased linearly (P=0.06; R2=0.17), while butyrate percentage (P=0.06; R2=0.21), acetate to propionate ratio (P=0.05; R2=0.22) and ammonia concentration (P=0.02; R2=0.39) in rumen fluid decreased linearly with increasing fat concentrations. Supplementation of fat had greater suppressive effects on methane production expressed as digestible DM intake in sheep than cattle, but had similar responses on digestibility and rumen fermentation. In conclusion, low concentration of fat in the diet may decrease methane emission without adversely affecting rumen fermentation; but it may lower fiber digestibility at high concentrations.

Clostridium perfringens challenge and dietary fat type affect broiler chicken performance and fermentation in the gastrointestinal tract

The aim of the present work was to examine how different fats commonly used in the feed industry affect broiler performance, nutrient digestibility and microbial fermentation in the gastrointestinal tract of broiler chickens challenged with virulent Clostridium perfringens strains. Two experiments were carried out, each including 480-day-old male broilers (Ross 308), which were randomly distributed to eight experimental groups using six replicate pens per treatment and 10 birds per pen. In Experiment 1, birds were fed diets containing soybean oil, palm kernel fatty acid distillers, rendered pork fat and lard. In Experiment 2, birds were fed diets containing rapeseed oil, coconut oil, beef tallow and palm oil. In both experiments, the birds were either not challenged or challenged with a mixture of three C. perfringens type A strains. Irrespective of the fat type present in the diet, C. perfringens did not affect broiler chicken body weight gain (BWG) and mortality in either of the two experiments. The BWG was affected by dietary fat type in both experiments, indicating that the fatty acid composition of the fat source affects broiler growth performance. In particular, the inclusion of animal fats tended to improve final BW to a greater extent compared with the inclusion of unsaturated vegetable oils. In Experiment 2, irrespective of the dietary fat type present in the diet, C. perfringens challenge significantly impaired feed conversion ratio in the period from 14 to 28 days (1.63 v. 1.69) and at 42 days (1.65 v. 1.68). In both experiments apparent metabolizable energy values were affected by dietary fat type. Irrespective of the fat type present in the diet, C. perfringens challenge decreased the digesta pH in the crop and ileum, but had no effect in cecal contents. Moreover, in Experiment 1, total organic acid concentration in the ileum was two to three times lower on soybean oil diets as compared with other treatments, indicating that C. perfringens as well as dietary fat type significantly affects microbiota activity in the broiler chicken gastrointestinal tract.

Вплив додецилсульфату натрію на фізіолого-біохімічні та цито-морфологічні властивості дріжджів родів Candida і Saccharomyces

Physiological, biochemical, cyto-morphological properties of initial strain Candida albicans ATCC 10331, Saccharomyces sp. КНУ 1 and their variants, which were cultivated in medium Saburo with anionic surfactant (SAS) sodium dodecyl sulfate (SDS) have been compared. It was shown that the effect of SDS was accompanied by disappearance of possibility to assimilate a number of substrates, but did not affect antibiotics sensitivity. They changed its morphology after 1 passage, diminution quantity of volutin, appearance of fat inclusion. Morphology of cells partially restored after 4-th passage.

Texture‐based classification of liver fibrosis using MRI

To investigate the ability of texture analysis of MRI images to stage liver fibrosis. Current noninvasive approaches for detecting liver fibrosis have limitations and cannot yet routinely replace biopsy for diagnosing significant fibrosis. Forty-nine patients with a range of liver diseases and biopsy-confirmed fibrosis were enrolled in the study. For texture analysis all patients were scanned with a T2 -weighted, high-resolution, spin echo sequence and Haralick texture features applied. The area under the receiver operating characteristics curve (AUROC) was used to assess the diagnostic performance of the texture analysis. The best mean AUROC achieved for separating mild from severe fibrosis was 0.81. The inclusion of age, liver fat and liver R2 variables into the generalized linear model improved AUROC values for all comparisons, with the F0 versus F1-4 comparison the highest (0.91). Our results suggest that a combination of MRI measures, that include selected texture features from T2 -weighted images, may be a useful tool for excluding fibrosis in patients with liver disease. However, texture analysis of MRI performs only modestly when applied to the classification of patients in the mild and intermediate fibrosis stages.

Ramadan and Sport: Minimizing Effects Upon the Observant Athlete

The intermittent fasting of Ramadan could affect various aspects of body physiology and biochemistry important to athletic success. Much of the available information on this subject has been collected from sedentary subjects or low-level competitors, often without well matched controls. Other issues requiring clearer definition include the duration of fasting, the local environment, the timing of observations, and changes in training, diet and sleep patterns. Sleep may be shortened or made good with daytime naps. Circadian rhythms of temperature, metabolism, hormonal secretions and physical performance may be disrupted and incidental activities curtailed. Disturbances of psychomotor performance include daytime sleepiness, impaired vigilance and slower reactions. Food intake is limited to night-time meals. Sedentary individuals sometimes exploit Ramadan to reduce body fat stores. Well disciplined athletes usually maintain energy balance unless daily energy expenditures are very high. Protein intake must allow for gluconeogenesis, and provide quality protein ingested around training times. Blood sugar levels are likely to fall over a long and active day, even if morning glycogen reserves are maximized. Metabolism of fat should be encouraged, beginning prior to Ramadan; inclusion of fat in the pre-dawn meal also slows gastric emptying. Daytime fluid depletion is inevitable if athletes exercise in the heat, but the immediate deficit can usually be made good at night. Some studies show an initial fluid depletion, with recovery as Ramadan continues, possibly reflecting changes in urine and sweat production. Top athletes can maintain training throughout Ramadan, although coaches sometimes reduce demands through a pre-competitive tapering of effort. Late night or early morning training requires negotiation with players who are not observing Ramadan, and dietary adjustments to maintain optimal plasma amino acid levels when training. Performance of repeated anaerobic exercise is impaired, but aerobic power and muscular strength show little change during Ramadan. Ratings of fatigue are increased, and vigilance and reaction times are impaired, particularly during the afternoon. Medical issues during Ramadan are few. Athletes with diabetes mellitus should seek a medical exemption from fasting, and prescribed drug schedules should be carefully maintained. There is no major increase of injury rates, but competitors may have difficulty in producing urine for doping controls. Logical measures to minimize the effects of Ramadan include the optimization of mood state, maintenance of training, minimization of sleep loss, appropriate adjustments of diet, and the monitoring of competitors for chronic dehydration. Future research should concentrate on the changes observed in top athletes, particularly women, with data collected in the late afternoon after a known period of fasting in a well defined environment. It will be important to ensure that the lifestyle of those studied has been optimized. Implications of chronic dehydration for doping control also merit further investigation. Current data suggest that the impact of Ramadan upon athletic performance is small relative to the precision of test procedures, although it may be sufficient to cause a loss of medals. Negative effects vary widely with the type of sport, the season when fasting is observed, the local culture and the discipline exercised by the athlete.

Longitudinal measurement of fetal thigh soft tissue parameters and its role in the prediction of birth weight

The aim of this study was to profile longitudinal changes in thigh muscle and fat with gestation and to determine whether thigh measurements can improve the prediction of birth weight (BW). A prospective longitudinal study of subcutaneous soft tissue measurements was conducted in 328 singleton fetuses at 28 and 37 weeks gestation. Estimated fetal weight (EFW) was calculated using abdominal circumference, femur length, biparietal diameter, and head circumference. The fetal abdominal subcutaneous tissue (FAST) and thigh muscle and fat show an increase with gestation. At 28 weeks gestation, the abdominal circumference, thigh fat, FAST, and EFW percentile were found to be significant predictors of BW. A combination of EFW percentile and thigh fat were found to be the optimal multivariate model at 28 weeks for predicting BW. At 37 weeks, BW prediction using EFW percentile, FAST, and thigh fat was the most accurate. The results revealed acceptable reproducibility for fetal thigh muscle and fat. This study provides reference ranges for thigh fat and muscle at 28 and 37 weeks gestation. The inclusion of fetal thigh fat in the algorithm improves the predictive power for birth weight. This information is important to explore the role of fetal thigh in the detection of aberrant growth.

The relationships among total body fat, bone mineral content and bone marrow adipose tissue in early-pubertal girls

Investigation of the physiologic relevance of bone marrow adipose tissue (BMAT) during growth may promote understanding of the bone-fat axis and confluence with metabolic factors. The objective of this pilot investigation was two-fold: (1) to evaluate the relationships among total body fat, bone mineral content (BMC) and femoral BMAT during childhood and underlying metabolic determinants and (2) to determine if the relationships differ by race. Participants included white and non-Hispanic black girls (n=59) ages 4–10 years. Femoral BMAT volume was measured by magnetic resonance imaging, BMC and body fat by dual-energy X-ray absorptiometry. Metabolic parameters were assessed in the fasted state. Total fat and BMC were positively associated with BMAT; however, simultaneous inclusion of BMC and body fat in the statistical model attenuated the association between BMC and BMAT. Differences in BMAT volume were observed, non-Hispanic black girls exhibiting marginally greater BMAT at age eight (P=0.05) and white girls exhibiting greater BMAT at age ten (P<0.001). Metabolic parameters conferred differential impact by race, such that, a positive association for BMAT and leptin (P=0.02) and adiponectin (P=0.002) in white girls while BMAT and insulin were inversely related in non-Hispanic black girls (P=0.008). Our findings revealed a positive relationship between BMAT, body fat and BMC, although body fat, respective to leptin, contributed partly to the relationship between BMAT and BMC. Despite large differences in total fat between non-Hispanic black and white, the relationship between BMAT and BMC was similar to white girls. However, this relationship appeared to be impacted through different mechanisms according to race.

PF.12 Longitudinal Data on Fetal Thigh Soft-Tissue Parameters and Its Role in the Prediction of Birthweight

ObjectiveTo profile longitudinal changes in the fetal mid thigh muscle and subcutaneous tissue measurements in fetuses with a normal growth velocity in euglycemic pregnancies and evaluate the association between mid...

Alternative Feeding Strategies to Maximize Fish Oil and Fish Meal Sparing in Largemouth Bass Culture while Maintaining Production Performance and Product Value

AbstractFeeding trials were conducted to determine (1) the optimal inclusion of poultry byproduct meal (PBM) and poultry fat (PF) as alternatives to fish meal (FM) and fish oil (FO) in diets for Largemouth Bass Micropterus salmoides and (2) whether the poultry‐based formulations could be used in conjunction with FO‐based finishing feeds in a strategy to minimize the use of marine‐derived ingredients while maintaining performance and fillet composition. In trial 1, fish (mean ± SE = 16.0 ± 0.5 g) were reared for 9 weeks on diets (∼40% protein, ∼10% lipid) containing graded levels of FM (0, 7.5, or 15%) and FO (0, 3, or 6%), with PBM and PF replacing FM and FO, respectively. The results indicated that complete replacement of marine feedstuffs with PBM and PF had no significant effects on production performance; all diets yielded equivalent weight gain (mean ± SE = 277 ± 45%), feed conversion ratio (FCR; 1.4 ± 0.4), and feed consumption (39 ± 6 g/fish), although fillet fatty acid profile reflected the diet. Based on these results, the 7.5% FM–0% FO and 0% FM–0% FO diets were further evaluated. In trial 2, fish (mean ± SE = 39 ± 3 g) were reared for 16 weeks on the 7.5% FM–0% FO or 0% FM–0% FO feeds, followed by an additional 12 weeks on the assigned diet or a 15% FM–6% FO finishing diet. The performance and fillet composition of these fish were compared with those of their counterparts that only received the finishing feed or a commercially available Largemouth Bass feed. All approaches yielded equivalent weight gain (mean ± SE = 496 ± 65%), FCR (2.0 ± 0.2), and feed consumption (407 ± 65 g/fish). Fillet fatty acid profiles reflected dietary intake, but finishing significantly increased the n‐3 fatty acid and long‐chain polyunsaturated fatty acid levels. The use of poultry‐byproduct‐based Largemouth Bass feeds may offer cost savings, and undesired effects on fillet nutritional value may be attenuated by the use of finishing feeds.