Effect Of Dietary Energy Concentration Research Articles

The effect of dietary energy concentration and lysine/digestible energy ratio on growth performance and nitrogen deposition of young hybrid pigs

AbstractAn experiment was conducted to examine the effects of dietary lysine/digestible energy (DE) ratio (g/MJ) and dietary energy concentration on growth performance and body composition of young hybrid gilts from 9·1 to 25·4 kg live weight. Seven pigs were assigned to each of 10 dietary treatments consisting of lysine/DE ratios from 0·6 to 1·4 in 0·2 g/MJ increments and two DE concentrations (14·25 and 16·40 MJ/kg). Food was provided ad libitum and at 25·4 kg all pigs were slaughtered and body composition was determined. Responses to lysine/DE ratios were different for each DE concentration. The pigs given the 16·40 MJ/kg DE diets had a higher daily live-weight gain (DLWG) and nitrogen deposition rate (NDR) than those given the 14·25 MJ/kg diets up to the 1·2 g/MJ lysine/DE ratio. Beyond this point no DE effects were evident. Lipid deposition rate (LDR) was higher for all 16·40 MJ/kg diets as compared with the 14·25 MJ/kg diets and decreased with increasing lysine/DE ratio. The 14·25 MJ/kg diets resulted in increasing efficiency of nitrogen and gross energy utilization with increasing lysinel DE ratio up to the 1·0 g/MJ ratio after which it declined. Efficiency of lipid utilization decreased with increasing lysine/DE ratio for all 14·25 MJ/kg diets. The 16·40 MJ/kg diets resulted in a decrease in nitrogen and gross energy utilization efficiency with increasing lysine/DE ratio while lipid efficiency decreased up to the 1·0 g/MJ lysine/DE ratio after which it increased. Young hybrid pigs given high energy diets appear to be less sensitive to dietary lysine/DE ratio than those given lower energy diets. The optimum lysine/DE ratio for the genotype tested from 9 to 25 kg live weight was of the order of 1·2 g/MJ for both DE concentrations. The maximum DLWG and NDR of the genotype tested over the live-weight range of 9 to 25 kg appears to be of the order of 620 and 17 g/day (106 g/day protein deposition rate) respectively.

Effect of dietary energy concentrations during the peri-ovulatory period on the in vivo and in vitro development of fertilized sheep ova

Results from a series of recent experiments involving superovulated ewes demonstrate the important influence of nutritionally-induced alterations in preovulatory progesterone concentrations on the subsequent in vivo and in vitro development of their fertilized ova (McEvoy et al, 1993 and 1995; Creed et al, 1994). In essence, these show that high-plane feeding can suppress preovulatory progesterone concentrations to such an extent that the subsequent development of the ova is impaired both in vivo and during in vitro culture. An important practical question however remains unanswered in that no attempt has been made to study the effects of dietary energy concentrations, as opposed to plane-of-nutrition, on progesterone concentrations and ovum development. As a result, recommendations regarding which energy sources should be used as supplements to pasture around mating time are a matter of conjecture. Furthermore, in arid environments, roughage feeds are often in short supply and therefore command a much higher price per unit of energy than concentrate diets. Under these conditions it is not unusual to feed all-concentrate diets at mating, yet there are no published data for their effects on ovum development and embryo survival.

Effect of dietary energy concentrations during the peri-ovulatory period on the in vivo and in vitro development of fertilized sheep ova

Results from a series of recent experiments involving superovulated ewes demonstrate the important influence of nutritionally-induced alterations in preovulatory progesterone concentrations on the subsequent in vivo and in vitro development of their fertilized ova (McEvoy et al, 1993 and 1995; Creed et al, 1994). In essence, these show that high-plane feeding can suppress preovulatory progesterone concentrations to such an extent that the subsequent development of the ova is impaired both in vivo and during in vitro culture. An important practical question however remains unanswered in that no attempt has been made to study the effects of dietary energy concentrations, as opposed to plane-of-nutrition, on progesterone concentrations and ovum development. As a result, recommendations regarding which energy sources should be used as supplements to pasture around mating time are a matter of conjecture. Furthermore, in arid environments, roughage feeds are often in short supply and therefore command a much higher price per unit of energy than concentrate diets. Under these conditions it is not unusual to feed all-concentrate diets at mating, yet there are no published data for their effects on ovum development and embryo survival.

The Effect of Dietary Energy Concentration on Calf Performance

At three locations, 120 calves were fed a high fat milk replacer at 10% of birth weight from d 5 through 13. On d 14, calves were assigned randomly within sex and date of birth to a 2 × 2 factorial arrangement of treatments. Treatments were (on a DM basis) high fat milk replacer (21.6%) and high fat starter (7.3%), high fat milk replacer (21.6%) and low fat starter (3.7%), low fat milk replacer (15.6%) and high fat starter (7.3%), and low fat milk replacer (15.6%) and low fat starter (3.7%). Milk replacer was fed at 8% of birth weight/d from d 14 to 35 and at 4% of birth weight/d from d 36 to 42. High fat replacer depressed DMI before and after weaning. High fat starter depressed DMI after weaning. Before weaning, calves gained more BW when fed low fat replacer. Calves fed low fat starter gained more BW after weaning. On d 56, BW were highest for calves fed low fat replacer and starter and lowest for those fed high fat replacer and starter. Growth or health of calves was not improved by fat addition to the diet.

Effect of energy density by dietary incorporation of fats on the performance of double-muscled bulls

The effect of dietary energy concentration by the addition of 2.5 or 5% hydrolysed fat residue or 5% lard was studied in double-muscled bulls of the Belgian white-blue breed. Average daily gain was 1.31 kg and was not significantly affected by the addition of fat, while dressing percentage was significantly increased from 68.4 for the control group to 69.3 for fat-supplemented groups, without modification of the carcass composition. It was not clear if the positive effect on carcass quality was specific to the fat supplementation. The dietary incorporation of hydrolysed fat residue had no negative effects on animal performance in comparison with lard.

Studies on the growth and carcass composition in Daldale wether lambs. 1. The effect of dietary energy concentration and pasture species

Thirty-two Daldale wether lambs were randomly allocated in groups of four and were grown from 23.3 � 0.4 kg liveweight until slaughter at a final full liveweight of 37.5 kg. Eight lambs were fed on a high energy diet (HE) ad libitum, eight lambs were given a low energy (LE) diet ad libitum, eight lambs grazed Trifolium repens L. (WC) pasture and eight others grazed Phalaris aquatica L. (PH) pasture. Those on the HE diet grew at 171 g/day, the lambs on the LE diet at 105 g/day, white clover lambs at 227 g/day and lambs on phalaris at 198 g/day. The HE lambs when compared with the LE, the grazed Trifolium repens L. (WC) pasture and eight others grazed Phalaris aquatica L. (PH) pasture. Those on the HE diet grew at 171 g/day, the lambs on the LE diet at 105 g/day, white clover lambs aat 227 g/day and lambs on phalaris at 198 g/day. The HE lambs when compared with the LE, the WC and the PH lambs, had significantly greater dressing percentage (54.7 compared with 48.8, 5 1.3 and 49.4 respectively), fat thickness over the 12th rib section (8.9 mm compared with 5.5, 5.6 and 4.8 mm), more omental fat ( + 15%, + 65%, and + 57%), kidney, perinephric and pelvic fat (+ 35%, + 85%, and + 54%), a greater amount of dissectable fat from the 9-10-11th rib (+ 15%, +30% and + 33%) and from the long leg (+ 16%, +34% and +40%), and a greater amount of carcass chemical fat (+ 19%, +27% and + 35%). No differences existed among the LE and the two pasture groups in carcass composition.Digestion of two diets (HE and LE) in the stomach and intestines was studied. The flow of digesta from the rumen was higher (+ 37%); the flow of digesta from the abomasum per unit of organic matter intake was higher (+ 47%) and the mean residence time of 51Cr-EDTA in the rumen was lower (-17%) for the LE diet than for the HE diet. There was a 23% higher concentration of acetic acid, and a 33% lower concentration of propionic acid, 6.5% less butyric acid and 30% less combined valeric acids.The greater amount of fat in the carcass of the sheep fed the high energy diet appears to be associated with the higher concentration of propionic acid in the ruminal volatile fatty acids and none of the other parameters of digestion. There may also have been a more eficient utilization of metabolizabe energy on the high energy diet.

Effect of dietary energy concentration, protein:energy and lysine:energy ratios on growth of pigs in the humid tropics

Forty-eight Landrace x Large White x Duroc pigs were used in each of two experiments to study the effect of diets with different protein and 1ysine:energy ratios on growth between 20 and 50 kg and on growth, and subsequent carcass characteristics, between 40 and 85 kg. The eight treatments in each experiment comprised a 2x4 factorial design. The factors were digestible energy (DE) of 12.6 and 14.2 MJ/kg diet and four crude protein and lysine levels at each dietary energy level. The diets were based on combinations of traditional feed ingredients and local agricultural byproducts. Daily feed allowance (g) was calculated in both experiments by the formula: 110 Wkg.0.75, where W is liveweight. Pigs given high-energy diets grew faster, with a better feed conversion ratio, than those given the low-energy diets. In both experiments, growth rate of pigs was faster and feed conversion efficiency improved linearly (P<0.05) with increasing protein:energy ratio. Mean feed and DE intakes were the same on all treatments within an experiment. For pigs at 85 kg, killing-out percentage declined with increasing protein : energy ratio. Eye muscle area increased and back-fat thickness decreased as the protein and lysine contents of the diets increased. It appears that a protein (g):energy (MJ DE) ratio of about 15.1 for growing pigs, and 12.7 for finishing pigs, optimises performance. Corresponding total lysine (g): energy (MJ DE) ratios were 0.7 1-0.77 and 0.63-0.64, respectively.

Effect of Dietary Energy Concentration on Performance of Heavy Egg-Type Hens at Various Densities in Cages

Three dietary energy levels (2,737, 3,003, 3,322 kcal./kg.) were fed to heavy egg-type hens housed in cages at densities of 1,320, 660, and 440 cm.2 of floor area per hen.Increasing the number of hens per cage reduced egg production. This was most pronounced with three hens per cage during the latter part of the experiment. Final body weight was reduced only with three hens per cage, and occurred to a greater degree at the end of the experiment. Mortality increased at the higher hen densities due to Marek’s disease and lymphoid leucosis. Hen density did not significantly affect egg weight, shell strength, Haugh units or meat and blood spots.Dietary energy level did not significantly alter overall hen-day egg production. However, egg production on the highest dietary energy level declined more rapidly in the latter months. Therefore, a high dietary energy content was not conducive to sustained egg production.There were no significant interactions between hen density and dietary energy level. But, with two or three hens per cage, egg production was consistently lower for hens fed the highest dietary energy level.As dietary energy level increased, feed intake decreased and feed efficiency increased. But energy intake increased resulting in heavier hens on the highest energy ration.The highest dietary energy caused an increase in egg size during the mid-part of the experiment. Otherwise, energy level did not affect egg weight, shell strength, Haugh units or blood and meat spots.It is concluded that although increases in dietary energy levels result in increased energy intakes and body weights of hens, high energy rations will not reverse the downward trend in egg production as density of caged hens increases. To the contrary, feeding of high energy rations to hens housed at high densities in cages may not be advisable, since egg production was consistently lowest under these conditions.

Effects of dietary energy concentration on production of broiler chickens

Eight least-cost diets with a determined range of metabolizable energy (ME) concentrations from 9.3 to 14.3 MJ kg-1 were formulated. Each diet was offered for about 12 weeks to two pens of about 100 broilers of each sex. Observations on feed consumption, liveweight and mortality were made weekly for each pen. Dressing percentages were recorded for samples of ten birds from each pen at two different Iiveweights. As ME concentration of the diets increased, birds grew faster and required less food, in terms of both total weight and total energy, to reach specified liveweights, although these effects were not marked when the dietary ME concentration was above 13.5 MJ kg-1. Feed conversion was less efficient at the same ME concentration when birds of each sex were taken to higher liveweights. Dressing percentage increased with increases in dietary ME concentration for males, but for females it tended to decline at the highest energy concentrations. Mortality was the same (2 per cent) on all diets.

The effect of dietary energy concentration on protein utilization during late pregnancy in ewes

SUMMARYFrom 62 days of gestation to parturition, 20 Finnish Landrace x Dorset Horn ewes were each offered one of four diets with roughage to concentrate ratios of 20:80; 40:60; 60:40 and 80:20, at daily metabolizable energy and digestible crude protein intakes of 490 kJ and 3·55 g/kg W0·75respectively. Plasma concentration of free fatty acids, glucose and urea were determined weekly, and nitrogen balance and digestibility trials were carried out at 70–80 and 130–140 days of gestation.On all treatments the concentration of plasma free fatty acids increased during pregnancy from approximately 200–600 μ-equiv./l and the concentration of glucose and urea decreased by approximately 25%.Digestibility coefficients for dry matter and organic matter increased from 58 to 68% and from 60 to 70% respectively as the proportion of concentrates in the diet increased and were not affected by stage of gestation. The apparent digestibility of nitrogen was not affected by the energy concentration of the diet.Between mid and late gestation there was a mean increase in daily nitrogen retention of 2·5 g and an improvement in the efficiency of nitrogen utilization of 19 percentage units.Nitrogen retention and the efficiency with which the apparently digested nitrogen intake was retained increased as the dietary energy concentration was increased. The mean daily increases in nitrogen retention were 0·0135 and 0·0039 g for each percentage unit increase in the concentrate portion of the diet at mid and late gestation respectively. The corresponding values for the improvement in the efficiency of nitrogen utilization were 0·13 and 0·10%.

Effects of dietary energy concentration on utilisation of energy by broiler chickens and on body composition determined by carcass analysis and predicted using tritium.

Synopsis Groups of 10 male, 10 female and 10 unsexed broiler chickens were given eight diets with energy concentrations ranging from 2.3 to 3.6 Mcal ME/kg in two experiments. Diets with a metabolisable energy concentration of about 3.1 Mcal/kg were found to be optimal for growth to a specified live‐weight. Carcass analysis gave much smaller values for nitrogen retention than did estimates from food intake and excreta. Retention measured by the latter method was influenced by the energy concentration of the diets. Body composition was influenced by both dietary energy concentration and sex. In general, the energy and fat content of the carcass increased with increasing dietary energy concentration although there were overall differences in fat content between male and female chickens, and also between birds in experiment 1 and experiment 2. Tritiated water was used to predict body water space enabling body composition to be estimated. Comparisons between determined body water content and tritiated water sp...

The effects of dietary energy concentration on growth rate and conversion of energy to weight gain in broiler chickens

Synopsis Eight diets, their metabolisable energy (ME) concentrations ranging from 2.3 Mcal/kg to 3.6 Mcal/kg (9.6 to 14.1 MJ/kg) were fed to each of four pens of broilers in two trials. Food intake was inversely related to energy concentration but the ME required by each sex to reach a given live‐weight was quite similar. Birds on the diets with a medium energy concentration (about 3.1 Mcal/kg (13.0MJ/ kg)) required slightly less ME than those on other diets and generally reached the required live‐weight earlier than those on other diets. Birds in the first trial required less of any particular diet than their counterparts in the second trial, reflecting the lower ambient temperatures recorded during the latter trial. Mortality recorded from 14 d of each trial was generally lower for birds on the medium energy concentration diets and dressed carcass percentage higher than those on other diets. The results of the present study are in agreement with the recent recommendation (National Research Council, 1971...

Effect of dietary energy concentration on sulfur amino acid requirements and body composition of young chicks.

Effect of dietary energy concentration on sulfur amino acid requirements and body composition of young chicks.

The effect of dietary energy content on the voluntary intake of pigs

1. An experiment to investigate the effect of dietary energy concentration on the voluntary intake and growth of pigs from 27·2 to 118·0 kg. (60 to 260 lb.) live-weight is described and the results discussed.2. From 27·2 to 50·0 kg. live-weight energy intake was substantially restricted and growth retarded by diets of low energy concentration but from 50·0 to 118·0 kg. there was little difference between diets in either energy intake or growth because daily food intake of the low energy diets was increased.3. Effects of diet on carcass quality as measured by full dissection were small except that killing-out percentage was lower on one of the low energy diets.4. It is concluded that limited differences in the energy concentration and palatability of ingredients are unimportant in formulating pelleted diets for self-fed pigs.

The Effect of Dietary Energy Concentration and Age on the Lysine Requirement of Growing Chicks

The Effect of Dietary Energy Concentration and Age on the Lysine Requirement of Growing Chicks