The effect of different dietary energy concentrations on the voluntary intake and growth of intensively-fed lambs

1969 ◽  
Vol 11 (2) ◽  
pp. 173-185 ◽  
Author(s):  
R. P. Andrews ◽  
M. Kay ◽  
E. R. Ørskov

SUMMARYIn a comparative slaughter trial which covered growth from about 16 kg to 40 kg live weight, five groups of six Romney × Swaledale lambs were offeredad libitumfive pelleted diets (A to E) in which rolled barley was gradually replaced by an 80 : 20 mixture of rolled oats : oat husks to the extent that the calculated metabolizable energy (ME) concentration fell from approximately 2–9 (A) to 2·5 (E) Mcal/kg DM.Although daily live-weight gains did not differ significantly between treatments, the daily carcass gain fell from 143 g/day on A to 105 g/day on E (P<0·05) whereas gut contents increased from 9·9% of live weight to 16·1% (P< 0·001) from A to E. Differences in efficiency of utilization of ME above maintenance were variable but for gross efficiency (i.e. retention/total ME intake), there was a significant decline from A to E.Dry-matter intakes for the whole experimental period were similar for all five diets, but initially intake was lower for diet E than for A (780v.927 g/day) and ultimately it was higher for E (1410v.1150 g/day). In a second experiment, involving diets A and E and a third diet of chopped dried grass, the pattern of intake and growth changed with live weight in a similar manner to that described above, except that appetite and growth on dried grass were consistently poorer. Daily variation in intake and rumen pH tended to be greater on the concentrate diets.It is suggested that, amongst other factors, the stage of maturity of an animal may influence the point at which the digestible energy content of the diet restricts dietary intake in preference to physical limitations.

1967 ◽  
Vol 9 (1) ◽  
pp. 107-113 ◽  
Author(s):  
J. B. Owen ◽  
W. J. Ridgman

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.


1976 ◽  
Vol 23 (2) ◽  
pp. 197-209 ◽  
Author(s):  
J. C. Tayler ◽  
K. Aston

SUMMARY1. Young adult and adult British Friesian female cattle (heifers and cows) which were lactating were individually fed on diets of grass silage ad libitum with supplements of dried grass, dried grass/barley or barley/groundnut in two randomized block experiments.2. In Experiment I, equal quantities of dry matter (DM) as dried grass in the form of a wafer (W), cob (C) or pellet (P) were given with the silage during weeks 8 to 18 of lactation, to three groups of 12 heifers. Silage DM intakes were respectively 14·2, 14·3 and 15·8 ± 0·43 g/kg live weight per day (P<0·05). Milk yields were 14·0, 15·6, 16·7 ± 0·35 kg/day (P< 0·001). Milk composition and live-weight change did not differ significantly.3. In Experiment II, five treatment groups of heifers and cows were offered silage with equal amounts of a supplement of either dried grass pellets (treatment 1) or dried grass/barley in the ratios of 2: 1 (treatment 2), 1: 2 (treatment 3), or a barley/groundnut supplement (treatment 4). In treatment 5 the cattle received the same supplement as in treatment 4, but at a 10% higher level. Silage DM intakes for treatments 1 to 5 during lactation weeks 6 to 22 were 8·64, 8·94, 7·96, 6·96, 7·63 kg/day (1, 2>4, P<0·01; 2>5, P<0·05). The intake of digestible organic matter, milk yields and live-weight changes over the whole experimental period were not influenced significantly by treatments 1 to 4, but in treatment 5 the milk was significantly higher in fat, protein and energy content than in treatments 1 to 4. Blood composition was normal and did not differ markedly between treatments.


1989 ◽  
Vol 48 (1) ◽  
pp. 149-155 ◽  
Author(s):  
S. M. Rhind ◽  
W. A. C. McKelvey ◽  
S. McMillen ◽  
R. G. Gunn ◽  
D. A. Eiston

ABSTRACTThe effect on the reproductive performance of Greyface (Border Leicester × Scottish Blackface) ewes of a low level food intake and associated loss of live weight from either 14 days before mating, or from the time of mating, until 11 to 26 days after mating, was investigated. Ewes (252) were allocated to one of three treatments with ewes within each treatment divided into two flocks (flock A: 16 ewes per treatment; flock B: 68 ewes per treatment). Ewes of treatment LL were given a ration providing proportionately 0·5 estimated metabolizable energy (ME) requirements for maintenance from 2 weeks before mating. Those of treatment HL were given a daily ration providing 1·5 estimated ME requirements for maintenance until mating and the restricted ration thereafter. Ewes of treatment HH were given the higher ration throughout the experimental period. Flock A ewes were slaughtered at 11 days post mating and flock B ewes at between 18 and 26 days post mating. Treatment differences in the ovulation rates of flock A ewes were not statistically significant but in flock B, ewes of treatment LL had a lower mean ovulation rate (1·81) than those of treatments HL (2·23) and HH (2·09) (P < 0·001). The lower ovulation rate of LL ewes relative to HL ewes in flock B was reflected in a lower mean potential lambing rate per ewe pregnant than in the HL treatment (1·58 v. 1·79; P < 0·01) and per ewe put to the ram (1·37 v. 1·65; P < 0·01). HL ewes had a slightly lower mean potential lambing rate per ewe pregnant (1·79 v. 1·97; P < 01) and per ewe put to the ram (1·65 v. 1·82; P < 0·05) than HH ewes. Ova wastage rates of LL + HL and HH ewes were 0·26 and 014 (P < 001) respectively at 24 days post mating. Values for LL and HL ewes (0·27 and 0·25 respectively) were not significantly different.Estimated mean conceptus lengths were 370, 500 and 1400 μin for LL, HL and HH ewes respectively (P < 0·05).It is concluded that low food intake before mating reduced the mean ovulation rate and low intakes after mating compromised embryo growth rate and induced a higher rate of ova wastage; this increase in the incidence of ova wastage was not significantly exacerbated by the low levels of intake prior to mating.


1983 ◽  
Vol 100 (1) ◽  
pp. 13-23 ◽  
Author(s):  
J. B. Moran

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.


2008 ◽  
Vol 52 (No. 9) ◽  
pp. 269-276 ◽  
Author(s):  
L. Bartoň ◽  
V. Kudrna ◽  
D. Bureš ◽  
R. Zahrádková ◽  
V. Teslík

A total of thirty-four Czech Fleckvieh (CF), Charolais (CH) and Charolais × Czech Fleckvieh (CH × CF) bulls with an average weight of 284 kg were included in the experiment and fed ad libitum two mixed diets: MS (based on maize silage) and LCS (based on legume-cereal and lucerne silages) with different concentrations of dietary energy until slaughter at the target live weight of 600 kg. The CF bulls consumed more dry matter (DM) of feed daily than the CH bulls (<i>P</i> < 0.05) and gained weight less efficiently than the CH × CF and CH animals (<i>P</i> < 0.01) during the entire experiment. The killing-out percentage was lower in the CF than in the CH × CF and CH (<i>P</i> < 0.05). The CH bulls received a higher score for carcass conformation and a lower score for carcass fatness (<i>P</i> < 0.01) than the CF bulls, had lower proportions of kidney and cod fat (<i>P</i> < 0.01) than the CH × CF and CF bulls, and produced the highest percentage of high-priced meat (<i>P</i> < 0.05) and the lowest percentage of separable fat (<i>P</i> < 0.001). The bulls on the MS diet were younger than the others at the end of the experiment (<i>P</i> < 0.01), gained weight more rapidly (<i>P</i> < 0.001), consumed less DM (<i>P</i> < 0.001) daily, utilized nutrients more efficiently over the entire experimental period (<i>P</i> < 0.001), and had a higher proportion of internal fat than the LCS bulls. It can be concluded that purebred CH bulls were superior to the other breed groups in most of the traits observed. The intensive diet based on maize silage increased average daily gains, reduced the time needed to achieve the target slaughter weight, and improved the feed efficiency of bulls.


1982 ◽  
Vol 35 (2) ◽  
pp. 277-280 ◽  
Author(s):  
H. Galbraith ◽  
K. J. Geraghty

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.


1970 ◽  
Vol 12 (4) ◽  
pp. 591-599 ◽  
Author(s):  
N. Jackson ◽  
T. J. Forbes

SUMMARYHerbage from the same timothy/meadow fescue/white clover sward was ensiled at four different dry matter contents. The resulting silages had dry matter contents of 19·0, 27·3, 32·3 and 43·2%, the dry matter content increasing with the length of the wilting period. An experiment was carried out to determine the voluntary intake of the silages. Each silage was given to 7 animals individually, the mean live weight of these being 334 kg.Although the silages made from wilted herbage were lower in digestibility than that made from unwilted herbage, wilting increased dry matter intake and metabolizable energy (ME) intake. The mean daily intakes of digestible organic matter were 53·0, 58·1, 59·6 and 59·6 g/kgW0·73, for silages of increasing dry matter content. The corresponding ME intakes, expressed as a multiple of the ME requirement for maintenance, were 1·17, 1·29, 1·30 and 1·28. The percentage of acetic acid in the silage dry matter was significantly (r= −0·56) and linearly related to voluntary intake. The relationship between lactic acid concentration and voluntary intake was significantly curvilinear (r= 0·48).


1987 ◽  
Vol 108 (1) ◽  
pp. 9-16 ◽  
Author(s):  
Margaret Gill ◽  
D. E. Beever ◽  
P. J. Buttery ◽  
P. England ◽  
M. J. Gibb ◽  
...  

SummaryThe effect of oestradiol-17β on the response to fishmeal supplementation of grass silage was studied in young growing cattle. Voluntary intake and live-weight gain were recorded over 63 days with 36 British Friesian male castrates (initial live weight (LW) 119 kg) offered silage alone (C) or with 50 (FM1), 100 (FM2), or 150 (FM3) g fishmeal/kg silage dry matter. Twelve calves were allocated to each of treatments C and FM3 and six to treatments FM1 and FM2. Half of the calves on each treatment were ear-implanted with oestradiol-17β (Compudose 365) at the start of the experiment. The calves on treatments C and FM3 were slaughtered after 75 days and chemical analysis conducted on half of each carcass. The silage had an organic-matter digestibility in vivo of 0·794 and was well-fermented, with a pH of 3·7. Intake averaged 24·2±0·42 g D.M./kg LW over all the treatments and live-weight gain was 0·77 kg/day on the silage alone. There was a significant (P < 0·05) interaction between fishmeal and oestradiol-17β, such that response to the hormone was observed only in the presence of fishmeal at 100 or 150 g/kg silage D.M. A similar interaction was apparent between fishmeal at 150 g/kg silage D.M. and oestradiol-17β in the final weights of empty body and carcass. This level of fishmeal also increased protein gain from 96 to 147 g/day and this was further increased to 179 g/day in the implanted animals receiving fishmeal. However, the overall effect of oestradiol-17β on protein gain was not significant. Gross efficiency of energy utilization was significantly (P < 0·01) increased by fishmeal supplementation suggesting an improved balance of nutrients compared with the silage alone diet.


1982 ◽  
Vol 98 (2) ◽  
pp. 395-404 ◽  
Author(s):  
G. D. Tudor ◽  
D. J. Minson

SUMMARYThe net energy values for growth and fattening of two artificially dried tropical grasses-, pangola (Digitaria decumbens) and setaria (S. sphacelata var. sericea cv. Nandi), of similar estimated metabolizable energy content (8·07 and 7·96 MJ/kg D.M.) were determined with cattle using a slaughter technique. Growing cattle with a mean initial weight of 175 kg were given equal quantities of dry matter of the two grasses at each of three planes of nutrition above maintenance for a period of 152 days.The initial energy, fat and protein content of the total body of the 24 test animals was estimated from regressions relating fasted live weight to theśe components, derived from 12 similar cattle slaughtered at the beginning of the feeding period. The final energy, fat and protein content of the test animals was determined directly by chemical analysis. The metabolizable energy (ME) content of the grasses was estimated from the level of digestible energy (DE) determined with eight cattle, assuming that ME = 0·815 DE.The cattle fed pangola gained more live weight, empty-body weight, fat, protein and energy than animals fed similar quantities of setaria. The net energy value for growth and fattening (NEf) was determined using regressions relating energy retention to the quantity of dry matter eaten. NEf in MJ/kg dry matter was 2·27 for pangola and 1·31 for setaria.Efficiency of utilization of ME for growth and fattening (kf) was.27·7% for pangola and 16·9% for setaria. These values for tropical grasses are lower than any values reported for temperate pasture species. Thus the lower efficiency of utilization of ME may cause the lower production of cattle which graze tropical grasses.It was concluded that as the kf values of different tropical grasses are not constant, kf values should be measured on a wider range of tropical grasses so that this factor can be taken into account when evaluating grasses in animal production systems.


1974 ◽  
Vol 18 (1) ◽  
pp. 67-73 ◽  
Author(s):  
D. Levy ◽  
Z. Holzer ◽  
H. Neumark ◽  
S. Amir

SUMMARYIn an experiment with group-fed cattle from 6 months of age to slaughter at 480 kg live weight two levels of feed intake: 1, ad libitum, 2, 85% of ad libitum amount, were combined with two ratios of concentrate to hay: a, 70: 30; b, 30: 70. In two further treatments, 3a and 3b, the cattle were fed diets a or b at 70% of ad libitum from 6 to 10 months and ad libitum thereafter.Daily gain during the first 124 days of the experiment was (in grams) 1293, 983, 1097, 846, 992 and 756, and from the 125th day to slaughter 735, 600, 796, 579, 830 and 714, for treatments la, lb, 2a, 2b, 3a and 3b, respectively. The decline in rate of gain from the first period to the second was inversely related to the level of feed intake and to the percentage of concentrates in the ration in the first period.Daily carcass gain was 582, 393, 532, 350, 531 and 368 g for treatments la, lb, 2a, 2b, 3a and 3b, respectively.The treatments that were switched over from 70% of ad libitum feed intake in the first period to 100% in the second (3a and 3b), exhibited considerable compensatory growth in the second period, but this was not sufficient to be of economic advantage.The overall ME requirement per kg of live-weight gain was inversely related to rate of gain. Of the six treatments, 2a (85% of ad libitum, 70% concentrate) was the most efficient (19·8 Mcal/kg live-weight gain).Animals on the 100% level of feed intake throughout the experiment (treatments la, lb) were significantly fatter than those on the other treatments.


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