Utilization Of Energy For Growth Research Articles

Average Daily Gain and Energy and Nitrogen Requirements of 4-Month-Old Female Yak Calves.

There is little information available on milk intake and energy and nitrogen requirements of growing yak calves. This study aimed to fill this important gap, as this information could be beneficial in designing a system to wean yak calves earlier than in natural time. We determined the average daily gain and energy and nitrogen balances and requirements of 4-month-old female yak calves (48.8 ± 2.45 kg, n = 8). The calves were allowed to suck once a day and were fed an ad libitum concentrate: hay diet at a ratio of 60:40. Milk intake averaged 540 ± 26 g/d, yielding 2.28 ± 0.112 MJ/d, which was 13% of the gross energy intake (GEI). The digestible energy intake (DEI):GEI ratio was 0.681, metabolizable energy intake (MEI):DEI was 0.913, and MEI:GEI was 0.621. The average daily gain of the calves was 433 ± 153.1 g/d, which consisted of 78.0 ± 8.99 g protein, 52.7 ± 23.74 g fat, and 302.3 ± 95.1 g water, that is, 18.0% protein, 13.0% fat and 69.8% water. There were 130.7 g of body solids and 9.06 MJ of energy in every kg of body mass gain. Of the MEI, 25.17 kJ were required for 1 g of body mass, 83.40 kJ for 1 g of body solids, and 2.62 kJ for 1 kJ of retained energy (RE), and RE was 36.6% of MEI. The maintenance energy requirement was 5.35 MJ/d, the efficiency of utilization of energy for growth (kg) was 0.72, and the heat increment of feeding for growth was 0.28 (1.55 MJ/d). Digestible nitrogen (N) was 0.685 while retained N (RN) was 0.489 of N intake. The N requirement for maintenance was 11.73 g/d or 0.61 g N/kg0.75 per day, while the biological value (BV) of N was 91.1%. The energy and N requirements for yak calves were relatively low, which could be explained, at least in part, by the high efficiency of utilization of energy and high BV of N when compared to other livestock. These findings could be beneficial in designing early weaning systems for the many Himalayan households depending on yak production for their livelihoods.

A mixture of carvacrol, cinnamaldehyde, and capsicum oleoresin improves energy utilization and growth performance of broiler chickens fed maize-based diet

A total of 210, 1-d-old Ross 308 male broiler chickens were used in an experiment to investigate the effects of a supplementary mixture containing 5% carvacrol, 3% cinnamaldehyde, and 2% capsicum on dietary energy utilization and growth performance. The 2 diets were offered ad libitum to the chickens from 0 to 21 d of age. These included a maize-based control diet and the control diet with 100 g/t of supplementary plant extracts. Dietary apparent ME, N retention (NR), and fat digestibility (FD) coefficients were determined in the follow-up metabolism study between 21 and 24 d of age. Feeding the mixture of carvacrol, cinnamaldehyde, and capsicum increased weight gain by 14.5% (P = 0.009), improved feed efficiency by 9.8% (P = 0.055), and tended to increase (P = 0.062) carcass energy retention and reduce (P = 0.062) total heat loss compared with feeding the control diet. There was a 16.1% increase (P = 0.015) in carcass protein retention but no difference in carcass fat retention. Feeding plant extracts improved dietary FD by 2.1% (P = 0.013) but did not influence dietary NR. Supplementation of plant extract resulted in a 12.5% increase (P = 0.021) in dietary NE for production (NEp), while no changes in dietary ME were observed. The experiment showed that although dietary essential oils did not affect dietary ME, they caused an improvement in the utilization of energy for growth. Plant extracts may affect metabolic utilization of absorbed nutrients. Studies that have focused solely on the effect of plant extracts on ME alone may well have not detected their full nutritional value.

The effect of lysine intake on energy partitioning and utilization in growing pigs

An experiment utilizing 12 castrated male pigs within a body weight range of 23 – 147 kg was conducted to ascertain whether the alteration of protein quality by varying the level of lysine intake is influencing total energy retention, heat production and therewith efficiency of energy utilization for growth. The animals were allotted to two treatments of a constant medium (11.5 g/d) or high lysine intake (13.5 g/d) level on the basis of an isonitrogenous diet at an energy intake level of 1.3 MJ ME/kg BW0.75. Representing a tool for determining body composition, at target body weights of 35, 55, 80, 115 and 145 kg measurements of deuterium dilution space were undertaken. Protein and lipid accretion were calculated by difference, assuming accretion to contain 23.8 and 39.0 kJ/g, respectively. The results show a significant effect (p < 0.05) between treatment groups for the values of energy retained in protein, thus ensuring the intended alteration by protein quality. Furthermore total energy retention, heat production (difference between ME intake and energy retention) and therewith energy utilization demonstrate independence from the composition of body weight (BW) gain. These observations confirm earlier results, but however, seem to be in contrast to the supposition of a constant efficiency for protein (kp) and fat (kf) accretion, respectively. This may be attributed to a variable kp, in fact to a smaller kp at minor values for protein accretion due to an increased whole body protein turnover. Lacking evidence from experimental data for advantages in using constant values for kp and kf to determine the accurate energy requirement for growth, a uniform value for the efficiency of total energy retention seems to be more adequate.

Utilization of energy for growth in lambs of the breed german merino landsheep

Based on energy deposition and energy intake the utilization of energy for fat and protein deposition and the mean energy utilization for growth as well as the energy requirement for maintenance were estimated in this study. Fifty-four male and 54 female lambs were fed at three feeding levels and slaughtered at various body weights (BW): 18, 30, 45, and 55 kg. Based on the method of the comparative slaughter technique the total body of each animal was analysed. From the data of empty-body gain, fat, protein and energy deposition in the different fattening periods was calculated. The utilization of metabolizable energy for growth and maintenance was estimated by a multiple linear regression model. In this regression model, a utilization of energy for fat deposition of 71% and for protein deposition of 30% was determined (R2 = 0.869). The requirement for maintenance was 520 kJ·kg BW − 0.75·d − 1. A slightly higher requirement for maintenance was determined for female lambs. The study indicated that the used regression model can be recommended to estimate the utilization of energy and the requirement for maintenance in growing lambs.

Fish-meal supplementation of grass silage offered to young steers: Effects on growth, body composition and nutrient efficiency

Growth and efficiencies of nitrogen and energy utilization for growth by 72 young British Friesian steers (initial live weight (LW) 110 kg) offered a well preserved, formic acid-treated, perennial ryegrass silage with and without supplements of fish meal were examined. Silage was offered either alone or mixed with 50, 100 or 150 g fish meal/kg silage dry matter (DM) and each diet was offered either ad libitum or intakes were restricted to 16, 19 or 22 g dietary DM/kg LW/day. Treatments were imposed over a period of 132 days. Body component weight gains were determined by comparative slaughter.Increasing the level of either feeding or fish meal increased rates of empty body weight gain linearly (P&lt;0·001) and curvilinearly (P&lt;0·05) respectively. Fish-meal supplementation increased rates of ash and crude protein gain (P&lt;0·001) but, in comparison with the curvilinear response to increasing level of feeding (P&lt;0·001), had small linear effects on fat gain (P&gt;0·01). Consequently, in terms of whole body composition, animals given fish meal were leaner than animals offered silage alone. Fish-meal supplementation had no significant effect on the composition of the carcass but increased the concentration of protein in the liver and gastrointestinal tract.The increase in nitrogen intake associated with feeding fish meal resulted in a reduction in the efficiency of nitrogen utilization as level of fish meal increased. Nitrogen intake required for maintenance was estimated to be 1·054 g/kg LW0·75. In spite of marked differences in the composition of the empty body-weight gain, there was no evidence to support an effect of fish meal on the efficiency of metabolizable energy (ME) utilization for growth (kf) which was estimated to be 0·346 on the basis of data scaled by LW0·75. ME intake required for maintenance (MEm) was estimated to be 0·536 and 0·502 MJ/kg LW0·75 for silage alone and the 150 g fish-meal level respectively.

Effects of varying dietary protein and energy supply on growth, body composition and protein utilization in gilthead seabream (Sparus aurataL.)

Diets formulated with increasing digestible energy (10–22 DE MJ kg−1) contents and decreasing digestible crude protein (DCP)/DE ratios (34–15 g MJ−1) were fed to triplicate groups of Sparus aurata in three consecutive trials. Fish were hand-fed to apparent satiation and voluntary feed intake was found to be dependent upon dietary DE content. Daily growth was regulated both by energy and protein intake and reached its maximum at high energy levels. Growth composition showed narrow limits regarding protein gain (157–190 g kg−1) and a wider range regarding lipid (55–210 g kg−1) deposition reflecting the dietary energy to protein supply. Energy utilization for growth was constant at a value of 0.50 regardless of energy intake. Efficiency of protein utilization for growth varied between 0.33 and 0.60 depending on the DCP/DE ratio in the diet. The optimal protein utilization for protein deposition was found to be at 0.47. These values allow daily energy and protein requirements for growing S. aurata to be quantified. This demonstrates that the optimal dietary DCP/DE supply changes with fish size, growth potential and daily feed intake.

The effect of method of conservation of grass and supplementation on energy and nitrogen utilization by lambs

An experiment was carried out in 1994 to examine energy and nitrogen utilization of lambs offered two contrasting grass-based diets. The two forages, which were from the same parent herbage, were grass silage and grass which was conserved by freezing. They were offered as sole diets or supplemented with either 250 or 500 g concentrates per kg total dry matter intake (DMI) to give a total of six experimental treatments. Seventy-two Dutch Texel × Greyface (Border Leicester × Blackface) lambs, consisting of 36 males which were initially 36 (S.D. 4·9) kg liveweight and 36 females which were initially 34 (S.D. 2·5) kg liveweight were used. Ensiling significantly increased apparent digestibility of dry matter, energy and nitrogen (P&lt;0·001), but had no significant effect on methane energy loss as a proportion of gross energy intake, metabolizable energy intake (MEI), heat production, energy retained, efficiency of utilization of energy for growth (kg) or nitrogen retention. Supplementation of forage with concentrates resulted in a curvilinear decrease in heat production expressed as a proportion of MEI (P&lt;0·05) and a linear increase in energy retention, expressed as an absolute value or as a proportion of MEI (P&lt;0·05). Supplementation of forage tended to increase kg when calculated using Agricultural Research Council estimates of maintenance energy requirements, but had no significant effect when alternative estimates of maintenance were used. It is concluded that ensiling had no effect on efficiency of utilization of energy or nitrogen as measured by indirect calorimetry.

The effect of differing forage:concentrate ratio and restricting feed intake on the energy and nitrogen utilization by beef cattle

Six Charolais cross steers (mean live weight 459 kg) were used in a partially balanced changeover design experiment with four 4-week periods. The energy and nitrogen utilization by cattle offered diets differing in forageiconcentrate ( F: C) ratio, but of equal metabolizable energy intake (MEI), were measured. The three diets were (1) high digestibility (D) grass silage offered ad libitum; (2) low D silage offered ad libitum and supplemented with sufficient concentrates to provide the same MEI as (1); (3) high D silage supplemented with the same F: C ratio as (2) and with intake restricted to the same MEI as (1) and (2). These three diet types were offered at two levels of energy intake, the higher level of energy intake having been achieved by adding further concentrates to diets 1 to 3. Gross energy intake (GEI) and faecal, urinary and methane outputs and heat productions were measured in respiration chambers for three days at the end of each period. When values were adjusted to equal MEI across the three diets, animals offered the restricted diet produced significantly less methane, expressed as a proportion of GEI ( P < 0.001), than those offered the other two diets. However, there was no difference in energy retention or the efficiency of utilization of energy for growth between the three diet types used in this study.

Studies with the Australian Cashmere Goat. II. Effects of dietary protein concentration and feeding level on body composition of male and female goats

The effects of plane of nutrition (ad libitum and 75% ad libitum) and dietary crude protein concentration (11.3, 16.0 and 20.9% crude protein) on body composition of male and female weaner goats were studied in a comparative slaughter experiment. The initial chemical composition of the body (water, ash, protein, fat) and dissectible tissue fractions of the carcass (muscle, fat, bone) of the experimental goats were estimated from regression equations, derived from a group of twelve comparable kids. The final chemical composition and carcass tissue distribution were determined directly by chemical and dissection analyses. There was no effect of dietary crude protein concentration on the chemical composition of the empty body weight (EBW) gain or on carcass tissue distribution. The lack of any response to dietary protein was attributed to similar levels of protein/energy available at the small intestine despite large differences in crude protein intake. Ad libitum feeding, however, resulted in significantly more fat (31.0 v. 22.6% of EBW gain) and less water (51.1 v. 56.4% of EBW gain) in the composition of the gain compared with restricted feeding. There was no effect of feeding level on protein or ash content of the body. Goats fed ad libitum had significantly less muscle (60.1 v. 62.5%) and more dissectible fat (19.5 v. 16.3%) in their carcasses than kids restricted in their intake. Females had significantly more fat (32.7 v. 22.4% of EBW gain) but less water (48.4 v. 57.9% of EBW gain) and nitrogen (2.2 v. 2.8% of EBW gain) in their body gain than did males. Similarly, the carcass of females contained more dissectible fat (22.6 v. 13.2%) but less bone (15.8 v. 19.3%) and muscle (58.5 v. 64.1%) than males. The efficiency of utilization of dietary energy for growth and fattening (kf) was similar (0.32) for all groups of kids.

The Preschool Child: Diet, Growth and Obesity

In this review the question of obesity in the pre-school child has been examined in three areas of interest: first, the extent of our knowledge of food intake and its relationship to growth in the young child; secondly, the difficulties in defining obesity on a practical level in this group, and thirdly the constraints in the examination of energy balance because of the limitations of techniques available for this type of work. The conclusion is that studies are needed to analyse factors regulating energy balance, and thereby explain why, in the very young child, there is an individual difference in the utilization of energy for growth, activity and basal processes.

The utilization by lambs of the energy and protein in dried pelleted grass treated with formaldehyde

ABSTRACTA primary growth crop of perennial ryegrass (cv. S24), containing 17% crude protein and 9·9 MJ metabolizable energy/kg dry matter, was artificially dried, ground through a 3·0 mm screen and pelleted either without further treatment (C), or after the application of formaldehyde (T) at a rate of 1 g/100 g crude protein. The C and T diets were each fed to 20 lambs for 77 days. Diets C and T were given ad libitum and at three lower planes of nutrition. Similar amounts of dry matter, nitrogen and digestible energy were consumed at each of the four planes of nutrition by lambs fed diets C and T. Carcass energy, fat and protein retention, and total body energy retention were measured by the comparative slaughter technique and did not differ between the diets (P&gt; 0·05). Metabolizable energy intake was calculated from digestible energy intake using the factor 0·81. The efficiency of utilization of the metabolizable energy for growth and fattening (kf) and the net energy value were calculated by linear regression analysis from the total body energy retention, the calculated metabolizable energy intake and dry-matter intake data scaled to M0·75. They did not differ between the diets (P &gt; 0·05), and were 0·370 (C) and 0·431 (T) for kf, and 2·09 (C) and 1·97 MJ/kg dry matter (T) for net energy.