Influence Of Dietary Energy Levels Research Articles

Effect of Dietary Energy Level during Late Gestation on Mineral Contents in Colostrum, Milk, and Plasma of Lactating Jennies.

This study investigated the effects of dietary energy levels during late gestation on mineral content in the plasma, colostrum, and milk of jennies postpartum. Twenty-four pregnant multiparous DeZhou jennies, aged 6.0 ± 0.1 years, with a body weight of 292 ± 33 kg, an average parity number of 2.7 ± 0.1, and similar expected dates of confinement (74 ± 4 days), were randomly allocated to three groups and fed three diets: high energy (12.54 MJ/kg, HE), medium energy (12.03 MJ/kg, ME), and low energy (11.39 MJ/kg, LE). Blood samples were collected from the jugular vein of each jenny at time points of 0 h, 24 h, 48 h, 5 d, 7 d, and 14 d after parturition. Additionally, milk samples were collected through manual milking, and an analysis of the mineral content was conducted. The results showed that compared with HE, both ME and LE significantly increased the levels of calcium (Ca), phosphorus (P), zinc (Zn), selenium (Se), molybdenum (Mo), and cobalt (Co) in the plasma and Ca, P, magnesium (Mg), copper (Cu), manganese (Mn), Zn, selenium (Se), molybdenum (Mo), and Co in the milk of jennies postpartum (p < 0.05); ME also increased the levels of potassium (K), iron (Fe), and Mn in plasma and K and Fe in milk (p < 0.05). The levels of Ca, K, Mg, P, Fe, Cu, Mn, Co, Se, Zn, and Mo in plasma and milk gradually decreased with increasing postpartum time. Their contents were the highest at 0 h postpartum, rapidly decreased after 24 h postpartum, and declined to the lowest on day 14 postpartum. The interaction between dietary energy level and postpartum time showed that although the concentrations of the minerals Ca, P, K, Mg, Fe, Cu, Mn, Zn, Co, Se, and Mo decreased in jennies' plasma and milk in the treatment groups with different energy levels as postpartum time increased, the pattern of change was also influenced by dietary energy level. The influence of dietary energy level in late gestation on the mineral content of milk and plasma during the postpartum colostrum phase was higher than that during the milk phase. In conclusion, this study demonstrated that, under the current experimental conditions, the mineral content of the colostrum, milk, and plasma of jennies after parturition was dependent on the dietary energy level during late gestation.

Effect of dietary energy level on growth performance and morphometric parameters of local barred chickens at the starter phase

An experiment was conducted to determine the influence of dietary energy level on the growth performance and morphometric characteristics of local barred chicks. The experiment lasted for 12 weeks. Three hundred and twenty day-old barred chicks were assigned to four different dietary treatments, having four replicates of 20 chicks each. Treatments consisted of D0, D1, D2 and D3 containing 2700, 2800, 2900 and 3000 kcal/kg of metabolisable energy respectively. The highest BW (868 g) and BWG (830 g) were recorded with treatment D1 and D3 (844 g and 804 g respectively). These values were significantly (P&lt;0.05) higher compared to D0 and D2. The feed conversion ratio were significantly (P &lt; 0.05) higher with treatments D0 and D2 as compared to treatments D1 and D3. Feed cost per kg of body weight was significantly (P&lt;0.05) lower for treatment D1 as compared to other treatments. Thus, metabolisable energy requirement of local barred chicks between 1 to 12 weeks is 2800 kcal/kg.Keywords: Barred chickens, dietary energy, starter phase.

Influence of dietary energy level on the production of breeding ostriches

A study was conducted to determine the influence of dietary energy level on the production of breeding ostriches. Six diets varying in ME content (7.5, 8.0, 8.5, 9.0, 9.5 and 10.0 MJ ME/kg feed) were provided to both males and females at an average rate of 3.4 kg/bird/day. Dietary protein and lysine levels were held constant respectively at 120 (g/kg feed) and 5.8 (g/kg feed). The trial ran over one breeding season and production records recorded included egg production, chick production, number of infertile eggs, number of dead-in-shell eggs and weight change of breeders. No significant differences were observed for total eggs produced per female per season (44.3 ± 7.6), number of chicks hatched (15.6 ± 4.1), number of infertile eggs (11.8 ± 3.9) and for number of dead-in-shell eggs (11.9 ± 3.1). Analysis of variance revealed no significant difference in the weight change of female birds on different treatments, although regression analysis revealed an increase of 2.4 kg per female bird per 0.5 MJ increase in dietary energy value of the feed. Significant differences in the weight change of male breeders were observed which ranged between 6.3 ± 2.7 kg and 18.4 ± 2.8 kg over the breeding season. Overall, the weight of male breeders increased by 1.9 kg per 0.5 MJ increase in dietary energy content (R2 = 0.09). It was concluded that the energy supplied for both male and female breeders was in excess of their requirements, since both sexes increased in weight over the season.

The influence of dietary energy level on the response to betaine (2001)

A total of 800 pigs were used to evaluate the influence of dietary energy level on the response to betaine in finishing pig diets. Dietary treatments were arranged in a 2 × 2 factorial with or without betaine and two energy density levels as the main effects. No betaine × energy interactions (P>0.05) were observed for the entire feeding period (51 to 210 lb) or for any of the three dietary phases. Pigs fed the high energy diets with added fat had (P<.05) greater ADG, lower ADFI, and improved F/G compared with pigs fed the low energy diets without added fat. Adding betaine to the diet had no influence on pig performance.

Influence of Dietary Energy Level on Hepatic70-kDa Heat Shock Protein Expression in Broiler Chickens Submitted to Acute Heat Stress

This experiment was carried out to study the effect of dietary energy on the colonic temperature and hepatic Hsp70 content in broiler chicken at room temperature and after heat stress conditions. Broiler chickens were reared up to 51 days of life, and fed diets containing high (HE -13,186 kJ ME/kg) or low (LE -12,139 kJ ME/kg) energy. At 21 and 51 days of age, the colonic temperature was measured at room temperature and liver samples were obtained for Hsp70 quantification by Western blotting analysis. It was also investigated at these ages the time course response of colonic temperature and hepatic Hsp70 level during heat stress (35º C/5 h). The data showed that at early age, at room temperature, colonic temperature or hepatic Hsp70 levels were not affected by dietary energy, but at 51 days of life low energy fed broilers had lower Hsp70 concentration in the liver. During heat stress, the increase in both colonic temperature and hepatic Hsp70 concentration were significantly less in high energy fed birds. The findings of this study suggest that hepatic Hsp70 synthesis is affected by dietary energy, and that broiler chicken fed high-energy diet can change the thermoresistance during acute heat stress.

Influence of dietary energy levels and form of diet on composition of fatty acids in subcutaneous adipose tissue of wethers

Effects of dietary energy levels and form of diet on the profile and accumulation of fatty acids in subcutaneous adipose tissue of wethers were investigated. Shorn wethers were randomly allocated to a 2 2 factorially arranged experiment (2 dietary energy levels × 2 dietary presentations × 14 replicates). Two diets were compiled on an isonitrogenous and isomineral basis to contain a medium (M) and high (H) level of metabolisable energy. Diets were presented in either loose or pelleted form and were fed ad libitum to the wethers from an initial weight of 24.9 ± 3.9 kg. Wethers were slaughtered at a predetermined slaughter weight of 43 kg and the subcutaneous adipose tissue was sampled for subsequent fatty acid analysis. Results suggests that dietary energy levels influence mainly the profile, rather than the amount of fatty acids deposited or synthesised. The latter appears to be a function of the degree of maturity of the animal and its residence period (length of grain feeding). It appears that the balance between the proportions of saturated and unsaturated fatty acids becomes increasingly important as greater concentrations of fatty acids accumulate in the subcutaneous adipose tissue. Results also suggest that the pelleting of high density diets may shorten the residence period and limit the accumulation of displeasing concentrations of unsaturated fatty acids in subcutaneous adipose tissue, which may yield more acceptable carcasses.

Influence of dietary energy levels on reproductive function and fertility in yearling beef heifers (1994)

Fifty-nine heifers were allotted to be fed at two different energy levels. One group gained 1.77 lb/hd/day, and the other 1.25 lb/hd/day. Estrus was synchronized with the MGA/prostaglandin system. After MGA removal, ovarian development was monitored daily by ultrasound (10 per group) until estrous was detected following the PGF injection. Heifers were inseminated artificially based on estrus behavior. Faster gaining heifers had higher final body condition scores and greater changes in body condition score. The high energy diet caused a slight (P=.11) decrease in AI pregnancy rate for purebred heifers.

The effects of dietary energy and crude protein concentration on growth and serum insulin-like growth factor-I levels of cattle that differ in mature body size

An experiment was conducted to examine the influence of dietary energy level (11.17 and 11.88 MJ ME kg−1 DM) and crude protein (CP) level (11, 13 and 15% DM basis) on growth and carcass composition and plasma insulin-like growth factor-I (IGF-I) levels of medium frame (MF) and large frame (LF) cattle. Dietary energy level or CP level did not influence the growth of MF steers. Averaged across energy levels, the growth of LF steers increased linearly (P &lt; 0.01; R2 = 0.60) with dietary CP level. No influence of protein level was observed on carcass tissue gain. Apparent CP and DM digestibilities increased (P &lt; 0.05) with increasing CP level on low- but not high-energy rations. Serum IGF-I levels were higher (P &lt; 0.05) in MF steers and in animals fed high-energy rations. Little or no association was observed between serum IGF-I levels and indices of growth or carcass composition. It was concluded that the growth of LF steers was improved on diets formulated to CP levels in excess of those currently recommended. However, the biological mechanism responsible for the improved growth is not clear. Key words: Steers, frame size, protein, energy, IGF-I

The influence of dietary energy levels with and without PCB induction on the growth of tilapia, Oreochromis niloticos x O. aureus

The effects of three dietary energy levels, 323, 365 and 408 Kcal/100g diet, on the growth performance of hybrid tilapia, Oreochromis niloticus x O. aureus, were studied. The experiment was carried out for 3 months in a recirculating rearing system. Growth and feed conversion ratios were significantly reduced (p<0.05) in fish exposed to 100 ppm polychlorinated biphenyl (PCB), fed high energy diets (365 and 408 Kcal/100g diet). The hepatic cytochrome P-450 and NADPH-cytochrome c reductase activities were also significantly (p<0.05) lower in PCB-treated fish fed high energy diets (365 and 408 Kcal/100g diet) than fish fed lower energy diet (323 Kcal/100g diet). The malic enzyme activity and the body lipid content in fish generally increased as the dietary energy level increased.

Factors Affecting Pelleting Response: 1. Influence of Dietary Energy in Broiler Starter Diets

Commercial day-old broiler cockerels were fed to 28 days of age to study the influence of dietary energy level on the effectiveness of the pelletized-crumbled process. Corn-soybean meal-meat protein diets were formulated to contain calculated levels of either 3100, 3150, or 3200 kcal metabolizable energy (ME)/kg of diet and fed in mash or crumbled form in three separate experiments. Dietary energy fed at 3100 to 3200 kcal ME/kg of diet, irrespective of feed form, resulted in no differences in mean body weight and feed consumption. Heavier body weights resulted from feeding a crumbled diet compared to an all-mash diet when the dietary energy level was 3150 kcal ME/kg of diet. Body weights were similar among feed forms when dietary energy levels were 3100 and 3200 kcal ME/kg of diet.The feed:gain was reduced .088, .078, and .042 in diets that contained 3100, 3150, and 3200 kcal ME/kg of diet, respectively, by feeding crumbled pellets as compared to all-mash diets. Toxic factors, such as soybean meal trypsin inhibitor, were not excessive.

Energy levels for broilers

AbstractOne of the most important decisions to be made in feeding poultry is to determine the level of energy that will balance growth, carcass quality and efficiency of feed utilization with profitability of production. Strict adherence to measures of efficiency such as feed:gain ratios has caused many to overlook the potential benefits of modifying energy levels periodically to adjust to changes in price relationships among ingredients and in cost and quality of the finished product. It has been consistently shown that if an adequate quantity of essential nutrients is maintained in relationship to dietary energy, increasing levels of dietary energy for broilers results in a more rapid rate of gain and improvement in feed conversion efficiency. Controversy exists regarding the influence of dietary energy levels on carcass composition and quality, but in general, carcass fatness increases as dietary energy level increases. Selecting the optimum dietary energy level for broiler diets depends upon many factors, not all of which have been fully defined or quantitated. Higher energy levels may allow for more rapid gains or for a greater quantity of meat to be produced in a given time so that capital costs of housing, equipment and labor may be reduced. On the other hand, the ingredient and production costs of higher energy diets in contrast to diets of lower energy density may negate the benefits of improved performance.

The Influence of Dietary Energy Level, Energy Source, Breed and Sex on Vitamin A Requirement in the Chick

REVIEW OF LITERATURETHE dietary requirement for vitamin A in the young chick has been estimated to be 1,200 U.S.P. units per pound of feed (National Research Council, 1954). Although this estimate is based on work prior to 1954 (Wilson et al., 1936; and Record et al., 1937), which showed that levels of 1,200 U.S.P. units and lower were sufficient for normal growth and health of chicks, considerable question has arisen as to its adequacy under current conditions.The development of the faster growing bird, the advent of the high energy ration and the production of vitamin A supplements of increased stability are among various factors which may be influential in changing the dietary requirement for vitamin A. Thus it is important that the requirements for such nutrients be reevaluated periodically. In some recent work, Scott et al. (1957), found that 400 to 600 U.S.P. units of vitamin A were …

The Influence of Dietary Energy Level, Energy Source and Breed on the Thiamine Requirement of Chicks

THE level of dietary energy and its relationship to nutrients other than protein has not been studied extensively in chickens. On the other hand, it appears that such factors should be studied in light of the present trend to use high energy diets. Theoretically it does not seem as probable that the need for nutrients such as thiamine would be elevated by increased energy levels to the same degree as protein, since their physiological function is widely different. However, it appears that a complete revaluation of our present recommended dietary standards should be made under today's genetic, feeding and management conditions.Although thiamine is generally found in abundance in the present-day practical poultry ration, its intimate role in the energy metabolic cycle of animals makes it a very feasible nutrient to study in so far as it may be affected by different sources and levels of energy. Evans and Lepkovsky…

Nutrition and Enzyme Action, Influence of Dietary Energy Level on Succinoxidase and Lactic Dehydrogenase of the Heart of Pregnant Swine

Nutrition and Enzyme Action, Influence of Dietary Energy Level on Succinoxidase and Lactic Dehydrogenase of the Heart of Pregnant Swine