scholarly journals Effects of live weight and energy intake on nitrogen balance and total N requirements of lambs

1975 ◽  
Vol 33 (3) ◽  
pp. 399-413 ◽  
Author(s):  
J. L. Black ◽  
D. A. Griffiths
Keyword(s):  
Body Weight ◽  
Energy Intake ◽  
Nitrogen Balance ◽  
Live Weight ◽  
Metabolizable Energy ◽  
N Balance ◽  
Total N ◽  
Biological Value ◽  
Protein Energy ◽  
N Requirement

1. Results of 298 nitrogen balance studies from experiments with male cross-bred lambs, ranging in weight from 3 to 38 kg, which had been either fasted, or fed entirely on liquid diets of varying protein content at various energy intakes up to ad lib. intake, were used to quantitatively describe the effects of the amount and quality of absorbed protein, energy intake and live weight on N balance and total N requirement of lambs.2. When N intake was less than the amount required, N balance was independent of energy intake, but linearly related to absorbed N and metabolic body-weight (live weight0·75). In the fitted relationship, the coefficient of absorbed N was shown to be an estimate of the biological value of absorbed protein and the coefficient of metabolic body-weight was an estimate of the loss of endogenous N in both urine and faeces. For the milk-based diets used in the experiment biological value was 0·72 and the total endogenous N loss in urine and faeces was 148 mg N/kg0·75 per d.3. When N intake was in excess of the amount required, N balance in lambs of a constant live weight increased linearly with metabolizable energy (ME) intake, at a rate that decreased with increasing live weight. Similarly at constant ME intake, N balance was a curvilinear decreasing function of metabolic body-weight. When N balance was expressed per unit metabolic body-weight, it was constant for lambs of all weights when ME intake was about 0·23 MJ/kg0·75 per d, but it decreased linearly with increasing metabolic body-weight for ME intakes above this level.4. N balance of fasted lambs was several times less than predicted by either of the relationships established for fed animals, and was found to be linearly related to metabolic body-weight.5. The effects of energy intake and live weight on the total N requirement of lambs were determined. When total N requirement was expressed per unit of energy intake, it was found to be constant at 0·9 g N/MJ ME for all lambs irrespective of live weight when ME intake was 0·23 MJ/kg0·7 per d. However, as ME intake/unit metabolic body-weight was raised above this level, N requirement/unit ME intake increased for lambs weighing less than c. 23 kg, but decreased for heavier animals.

Energy intake and patterns of growth for male and female fallow deer of two genotypes, between 10 and 21 months of age

2000 ◽  
Vol 70 (2) ◽  
pp. 335-342
Author(s):  
R.C. Mulley ◽  
G.W. Asher ◽  
J.S. Flesh ◽  
K.T. O’Neill ◽  
J. Ferguson
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Energy Intake ◽  
Live Weight ◽  
Fallow Deer ◽  
Metabolizable Energy ◽  
Dama Dama ◽  
Significant Difference ◽  
Gross Energy ◽  
Feeding Systems

AbstractEuropean (no. = 36) and hybrid (¼ Mesopotamian, ¾ European; no. = 36) fallow deer (Dama dama) were evaluated for weight gain and energy intake from 10 to 21 months of age. Twelve each of bucks, does and castrated males (haviers) were tested for each genotype, in both concentrate-fed and pasture-based feeding systems. Based on weekly weighing hybrids (H) in each of the sex classes grew more rapidly (5 g/day across all groups) than the European (E) fallow deer (P < 0·05). Haviers given concentrates grew significantly faster than pasture-fed haviers (P < 0·01), whilst does grown on pasture grew significantly faster than those given concentrates (P < 0·01). There was no significant difference in pattern of growth between bucks on pasture and those given concentrates (P > 0·05). Does grew significantly less (P < 0·01) than bucks and haviers in spring, summer and winter but environmental differences between years could not be accounted for in the analysis.Animals of all sexes and genotypes experienced rapid growth from 10 to 12 months of age (spring) and this was associated with energy intakes according to metabolic body weight (M0·75) these ranging between 0·8 and 1·1 MJ metabolizable energy (ME) per kg M0·75 per day. There were significantly (P < 0·01) higher levels of energy consumed by H does and haviers in the summer, compared with their E counterparts but this was not associated with greater growth rates. However, H does had significantly higher (P < 0·01) dressing proportions at slaughter than E does. The energy intake on a metabolic body weight basis for most groups declined to between 0·7 and 0·8 MJ ME per kg M0·75 per day from 12 to 21 months of age, except for the does, which declined even further to between 0·5 and 0·6 MJ ME per kg M0·75 per day from 17 months of age.There were no significant differences between E and H deer for energy intakes per M0·75, and H deer were slightly more energy efficient than their E counterparts in terms of growth rate in relation to annual gross energy intake. The food intake : weight gain ratio increased considerably for both genotypes after 14 months of age, indicating the desirability for slaughtering as soon as animals reach the target live weight. It was concluded that the crossbreeding system described is production efficient and produced offspring that reached slaughter weight sooner than E fallow deer and thereby produced carcasses with a greater wholesale value than their E counterparts of the same age.

Accretion of total protein and individual amino acids by organs and tissues of growing lambs and the ability of nitrogen balance techniques to quantitate protein retention

1993 ◽  
Vol 57 (2) ◽  
pp. 237-245 ◽  
Author(s):  
J. C. MacRae ◽  
A. Walker ◽  
D. Brown ◽  
G. E. Lobley
Keyword(s):  
Amino Acids ◽  
Body Weight ◽  
Intestinal Tract ◽  
Live Weight ◽  
N Balance ◽  
Total Amino Acid ◽  
Total N ◽  
Comparative Slaughter ◽  
Total Body ◽  
Gastro Intestinal Tract

AbstractTwelve Suffolk-Finn Dorset lambs were reared from 25 to 40 or 25 to 55 kg body weight on either pelleted dried grass or a ration of pelleted grass plus barley (ratio 1:1) in a comparative slaughter experiment designed to determine the amounts of total nitrogen and individual amino acids accreted in different body components during growth. Nitrogen (N) balance measurements were determined frequently during this growth phase and accumulated N retentions were compared with the total N accretion determined by comparative slaughter. Total N and individual amino acids accumulated in carcass, wool, skin, offal and blood, head and feet, gastro-intestinal tract and liver were linearly related to body weight in all cases other than for cysteine in carcass. At 25 kg live weight, proportionately 0·52 of total body N was in carcass components, 0·115 in wool, 0·08 in skin, 0·10 in offal and blood, 0·095 in head and feet, 0·06 in the gastro-intestinal tract and 0·02 in liver. However as the animals grew from 25 to 55 kg, 0·256 of the total N accretion was in wool, which was rich in cysteine (98 g/kg total amino acid). Carcass accretion represented only 0·449 of total body N accretion. The N balance technique overestimated net protein accretion by 0·24 (s.e. 0·036).

scholarly journals Nitrogen balance in relation to energy intake in entire male pigs weighing 75 kg

1986 ◽  
Vol 55 (1) ◽  
pp. 201-207 ◽  
Author(s):  
A. C. Dunkin ◽  
J. L. Black ◽  
K. J. James
Keyword(s):  
G Protein ◽  
Energy Intake ◽  
Nitrogen Balance ◽  
Crude Protein ◽  
Live Weight ◽  
Liquid Diet ◽  
Metabolizable Energy ◽  
Entire Male

1. Nitrogen balance (NB) was determined in entire male pigs weighing 75.6 (SE 0.56) kg and given 1.43 MJ metabolizable energy (ME)/kg live weight (LW)0.75 per d of semi-synthetic liquid diets which varied in crude protein (N x 6.38):ME from 2.5 to 14.5 g/MJ. Maximum NB of 20.8 g/d was reached with diets containing at least 6.2 g protein/MJ ME.2. The relation between energy intake and NB was then examined in pigs of comparable live weight (mean 73.8 (SE 0.39) kg) and receiving a liquid diet not limiting in protein. The diet, containing 10.0 g protein/MJ ME, was given at eight rates from 0.24 MJ ME/kg LW0.75 per d to ad lib. by approximately equal increments. Two animals were allocated to each level and two animals were fasted during the balance period.3. The animals fed ad lib. achieved a mean intake of 1.84 MJ ME/kg LW0.75 per d. NB increased linearly as ME intake increased up to 27.6 MJ/d (1.096 MJ/kg LW0.75per d) but thereafter remained constant at 22.8 g N/d.

scholarly journals Protein requirements of growing lambs

1973 ◽  
Vol 30 (1) ◽  
pp. 45-60 ◽  
Author(s):  
J. L. Black ◽  
G. R. Pearce ◽  
D. E. Tribe
Keyword(s):  
Energy Intake ◽  
Protein Intake ◽  
Milk Proteins ◽  
Live Weight ◽  
Metabolizable Energy ◽  
N Balance ◽  
Net Energy ◽  
Protein Requirements ◽  
Reference Protein ◽  
Group 2

1. The protein requirements of lambs were established by measuring nitrogen balance in seventy-four animals given liquid diets which passed direct to the abomasum. Four groups of lambs weighing approximately 8 kg (group 1), 13 kg (group 2), 21 kg (group 3) and 30 kg (group 4) received diets in which 0·10, 0·15, 0·20, 0·25, 0·30, 0·35 or 0·40 of the digestible energy was provided as protein (DPE:DE ratio) and a gross energy intake of from 1·30 to 1·42 MJ/kg0·73 per d.2. When the protein requirements were taken to correspond to the protein intake at the point of intersection of the line describing the increase in N balance with increase in protein intake and the line representing the maximum N balance, values of 0·25, 0·23, 0·17 and 0·12 DPE:DE ratio were obtained for groups 1–4 respectively. The requirements expressed in these terms can be applied only to lambs fed on liquid diets which contain milk proteins and escape fermentation in the rumen. To enable the results to be applied to lambs given other diets, the requirements were expressed as g reference-protein (defined as a theoretical protein with the ideal pattern of amino acids) per MJ net energy and were 11·6, 10·4, 8·0 and 6·2 for groups 1–4 respectively. The relationship between protein requirement (Y, g reference protein/MJ net energy) and live weight (X, kg) was: Y = 13·4–0·242X.3. The influence of energy intake on protein requirements in lambs is discussed and it is concluded that the results obtained are applicable to lambs given a metabolizable energy intake of more than about 1·75 times their maintenance requirement.4. Application of the estimated requirements to ruminant lambs and methods of formulating diets to supply the required quantity of reference protein/MJ net energy are discussed.

scholarly journals Nitrogen balance in Indian preschool children receiving the safe level of protein at varying levels of energy

1981 ◽  
Vol 46 (2) ◽  
pp. 295-300 ◽  
Author(s):  
Ashok K. Iyengar ◽  
B. S. Narasinga Rao ◽  
Vinodini Reddy
Keyword(s):  
Body Weight ◽  
Preschool Children ◽  
Energy Intake ◽  
Nitrogen Balance ◽  
Protein Intake ◽  
Energy Levels ◽  
N Balance ◽  
Minimum Level ◽  
Safe Level

1. A study was carried out to determine the effects of varying the level of energy intake on nitrogen balance in preschool children receiving the safe requirement level of protein, determined in an earlier study.2. Seven preschool children received four energy levels, i.e. 293, 334, 376 and 418kJ/kg body-weight at the safe level of protein intake of 1·75 g/kg body-weight and N balance determined.3. The N balance decreased with a decrease in energy intake. However, the N balance was positive at all levels of energy intake studied.4. Results indicated that at a protein intake of 1·75 g/kg body-weight the minimum level of energy intake for a retention of 40 mg N/kg body-weight in these children was found to be 326·2±45·5 (mean ± SD) kJ/kg body-weight. Below this energy intake the safe level of protein intake became inadequate.

The effect of level and pattern of energy intake during late pregnancy on the performance of housed Scottish Blackface ewes

1973 ◽  
Vol 16 (2) ◽  
pp. 165-171 ◽  
Author(s):  
T. H. McClelland ◽  
T. J. Forbes
Keyword(s):  
Body Weight ◽  
Energy Intake ◽  
Post Partum ◽  
Body Weight Loss ◽  
Late Pregnancy ◽  
High Energy ◽  
Metabolizable Energy ◽  
Feeding Period ◽  
Total Period ◽  
Constant Energy

SUMMARYSixty Scottish Blackface ewes were used in a 2 × 2 factorial experiment in which two levels of metabolizable energy (ME) were given during the final 6 weeks of pregnancy. In two treatments 1600 and 2000 kcal M E were given daily over the total period while in the remaining treatments daily ME intakes were 1200 and 1600 kcal ME during the first 3 weeks of the feeding period and 2000 and 2400 kcal ME during the last 3 weeks. Digestible crude protein (DCP) intakes were constant at approximately 30 g per head daily in the constant energy treatments and 15 and 45 g per head daily in the first and second periods respectively for the low-high energy treatments.Energy intake had no statistically significant effect on lamb birth weight nor on ewe net body-weight change (change from the start of the experimental feeding period to immediately post partum). Ewes on low-high energy intakes had a significantly lower net body-weight loss than did ewes on constant energy intakes. Pattern of feeding had no significant effect on lamb birth weights. Negative nitrogen balances were found during the first feeding period where the daily DCP intake was approximately 15 g per head.

scholarly journals The nutritive value of rumen micro-organisms in ruminants

1983 ◽  
Vol 50 (2) ◽  
pp. 471-478 ◽  
Author(s):  
E. Storm ◽  
E. R. Ørskov ◽  
R. Smart
Keyword(s):  
Nutritive Value ◽  
Live Weight ◽  
N Balance ◽  
Biological Value ◽  
Energy Inputs ◽  
N Input ◽  
True Digestibility ◽  
Gross Energy ◽  
Micro Organisms

Four experiments were conducted with eighteen lambs sustained entirely by intragastric nutrition at gross energy inputs varying from 430 to 860 kJ/kg live weight0·75 (W0·75). Isolated rumen micro-organisms (RMO) were infused into the abomasum in quantities varying from 0 to 2 g digestible N/kg W0·75 to assess the increase in N balance as a result of increasing RMO input when N was limiting.The over-all utilization of N from RMO (RMO-N) could be described by the equation y = 0·543 x −0·457, residual SD = 0·037, where y is the N balance and x is the abomasal input of RMO-N, both expressed in g/kg W0·75. Thus the coefficient of efficiency of utilization of infused RMO-N was 0·543 (SE 0·008). The coefficient of efficiency of utilization of RMO-N truly digested (i.e. the biological value) was 0·659 (SE 0·015).The RMO-N input (mean with SE) at N equilibrium was 0·843 (0·009) g/kg W0·75. The true digestibility of RMO-N was 0·813 (0·004). The urinary N excretion when no N was infused was 0·329 (0·008) g/kg W0·75 and the N excreted via the faeces with zero N input was 0·036 (0·009) g/kg W0·75.

The effects of live weight at weaning on growth rate and carcass composition at different stages of maturity in Scottish Blackface lambs fed on two different diets

1988 ◽  
Vol 47 (3) ◽  
pp. 401-409 ◽  
Author(s):  
J. M. Doney ◽  
J. A. Milne ◽  
T. J. Maxwell ◽  
Angela M. Sibbald ◽  
A. D. M. Smith
Keyword(s):  
Weight Gain ◽  
Live Weight ◽  
Relative Difference ◽  
Carcass Composition ◽  
Metabolizable Energy ◽  
Energy Ratio ◽  
Weaning Weight ◽  
Slaughter Weight ◽  
Protein Energy ◽  
The Difference

ABSTRACTThe effects of live weight at weaning on carcass composition were studied with 104 Scottish Blackface lambs offered two diets differing in protein: energy ratio. Groups of lambs were slaughtered at initial live weights of 24·1 (s.e. 1·48) kg (LL) and 28·9 (s.e. 1·67) kg (IL) and at 33 kg, 38 kg, 43 kg, 53 kg and mature live weight.Lambs were offered two diets — low protein: energy ratio (LP, 122 g crude protein (CP) per kg dry matter (DM): 10·4 MJ metabolizable energy (ME) per kg DM) and high protein: energy ratio (HP, 176 g CP per kg DM: 10·4 MJ ME per kg DM). The LP diet was offeredad libitumand the HP diet was restricted to a similar mean level. Muscle, fat and bone tissues in the carcass were separated and weighed and the carcass and non-carcass component tissues were analysed for chemical fat, protein and ash.Daily live-weight gain (DLWG) of HP lambs (148 (s.e. 8·1) g/day) was significantly higher than that of LP lambs (118 (s.e. 8·1) g/day;P< 0·05) and food conversion ratios were lower up to a live weight of 43 kg (P< 0·05). There were no differences in intake or DLWG between LL and IL lambs. Mature live weight (73·3 (s.e. 1·79) kg) was not related to weaning weight or post-weaning diet.There was no effect of diet on carcass composition at any slaughter weight but LL lambs had a higher fat proportion than IL lambs, which was significant (P< 0·05) at 33 kg only. During the feeding period, the increment of fat tissue per unit increase in live weight (348 (s.e. 15·8) g/kg LW) was not affected by live weight at the start of the diet. The difference between LL and IL lambs in fat proportion was directly related to the difference in weight gain required to reach slaughter weight. The difference was not a function of stage of maturity but only of weaning weight, itself largely determined by pre-weaning nutrition. At higher slaughter weights the relative difference decreased and became non-significant. Hence lambs lighter at weaning would be less suitable than heavier lambs for the production of light-weight lean carcasses.

Aspects of nitrogen utilization in Asiatic water buffalo and Zebu cattle

1983 ◽  
Vol 100 (1) ◽  
pp. 13-23 ◽  
Author(s):  
J. B. Moran
Keyword(s):  
Nitrogen Balance ◽  
Water Buffalo ◽  
Energy Content ◽  
Live Weight ◽  
Metabolizable Energy ◽  
Nitrogen Excretion ◽  
Zebu Cattle ◽  
Dietary Nitrogen ◽  
Faecal Nitrogen ◽  
Urinary Nitrogen

SUMMARYThe results of 62 comparative digestibility and nitrogen balance trials of Asiatic water buffalo and Zebu cattle fed the same roughage or mixed diet were analysed to test for species differences in various nitrogen input-output relationships. The influence of dietary metabolizable energy content on the utilization of dietary or apparently digested nitrogen (ADN) was also investigated.There was no difference between buffaloes and Zebus in their ability to digest dietary nitrogen. The true nitrogen digestibility was calculated to be 81% and the metabolic faecal nitrogen excretion to be 0·36 g N/lOOg dry-matter intake. The buffaloes had lower rates of excretion of urinary nitrogen per unit increase in ADN, and at the same intake of ADN (143 mg/kg live weight/day), they had the higher nitrogen balance: 58v.48 mg/kg live weight/day. Dietary metabolizable energy content did not affect the utilization of digested nitrogen.Estimates of metabolic faecal nitrogen and endogenous urinary nitrogen excretions and of maintenance requirements for digested nitrogen were similar to those of tropical large ruminants reported by other workers. On low-quality (0·8% N) or medium-quality (1·6% N) diets, it was calculated that buffaloes would have nitrogen balances.

A note on the response of British Friesian steers to trenbolone acetate and hexoestrol, and to alternation in dietary energy intake

1982 ◽  
Vol 35 (2) ◽  
pp. 277-280 ◽  
Author(s):  
H. Galbraith ◽  
K. J. Geraghty
Keyword(s):  
Growth Hormone ◽  
Energy Intake ◽  
Live Weight ◽  
Metabolizable Energy ◽  
Dietary Energy ◽  
Plasma Urea ◽  
Trenbolone Acetate ◽  
Blood Constituents ◽  
Dietary Energy Intake ◽  
Main Effects

ABSTRACTFour steers from a group of eight British Friesian steers were implanted with 300 mg trenbolone acetate and 30 mg hexoestrol at the beginning of a 90-day trial period. The remainder were untreated. They were offered diets that varied in estimated content of metabolizable energy as follows (MJ/day): day 0 to 34 (period A), 100; day 35 to 60 (period B), 50; and day 61 to 90 (period C), 75 increasing to 110. Implanted steers gained significantly more live weight in periods A and C, and lost less in period B, than controls. Implanted steers had significantly elevated concentrations of plasma glucose in period A, and lower values for plasma urea and serum albumin throughout. Differences between control and implanted steers for the other blood constituents studied, including growth hormone, insulin and prolactin, were small and not significant. The main effects of changes in dietary energy intake on blood composition included significant increases in both groups of animals in the concentration of free fatty acids and growth hormone during underfeeding (period B). These concentrations decreased in period C, concomitant with significant increases in the concentrations of insulin and prolactin.

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