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PubMed1987

Feeding combinations of dry corn and wheat to finishing lambs and cattle.

Two finishing trials, one with lambs and one with cattle, were conducted to determine the effect of combinations of dry corn (whole or rolled) with dry rolled wheat on animal performance. The cattle (mixed crossbred yearlings) trial also evaluated methods of getting cattle to full feed by stepping-up using either grain combinations or dry rolled corn and then feeding the appropriate grain combination. In the lamb trial, as the level of dry whole corn increased in the diet of 80 Rambouillet X Suffolk lambs (29 kg), feed intake (linear, P less than .01), gain (linear, P less than .01; quadratic, P less than .15) and feed efficiency (linear, P less than .01; quadratic, P less than .15) were improved. The major improvement occurred in the first 30 d of feeding when feed efficiency was improved (linear, P less than .01; quadratic, P less than .01) by the inclusion of dry whole corn. In the cattle trial (272 mixed crossbred yearling cattle, avg = 358 kg), as the level of dry rolled corn increased, feed intake (linear, P less than .01), gain (linear, P less than .01; quadratic, P less than .01) and feed efficiency (linear, P less than .05; quadratic, P less than .05) were improved. Cattle fed 67 or 33% dry rolled corn with 33 or 67% dry rolled wheat gained 4% faster and 4.4% more efficiently than the average performance of cattle fed 100% corn or wheat. Cattle stepped-up on dry rolled corn and then switched to 100% wheat, tended to gain faster (.1 kg/d) than cattle stepped-up on 100% wheat.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1992

Influence of increasing photoperiod and toe clipping on breast buttons of turkeys.

Two 17-wk experiments compared the effects of an increasing photoperiod treatment (INC) versus a constant photoperiod treatment (23H), and intact toes versus clipped toes, on the breast button incidence and performance of heavy tom turkeys. Under INC, the photoperiod was increased gradually from 8 to 23 h between 4 and 16 wk. Under 23H, the photoperiod remained constant at 23 h. Use of INC versus 23H resulted in a significant reduction in breast button incidence at 17 wk in both experiments (P less than .05). Toe clipping had no effect on breast button incidence. The presence of breast buttons was positively correlated with body weight at 12 wk, and area of unfeathered skin over the keel at 17 wk. In Experiment 1, the photoperiod treatments had no significant effect on 17-wk body weight or mortality, but the INC treatment had an adverse effect on feed efficiency (P less than .05). In Experiment 2, turkeys reared under INC were heavier at 17 wk (P less than .05), with similar feed efficiencies. Mortality was significantly lower on INC than 23H up to 12 wk in Experiment 2 (P less than .05). Turkeys with intact toes were .44 kg heavier than turkeys with clipped toes at 17 wk in both experiments (P less than .05) and had similar feed efficiencies. Mortality to 4 wk was lower for turkeys with intact than clipped toes in Experiment 2 (P less than .05). Increasing photoperiod treatments have potential for improving turkey performance, survival, and carcass quality.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗

PubMed1997

Effects of dietary energy intake and protein concentration on performance and visceral organ mass in lambs.

Eighty-eight early-weaned Hampshire x Targhee crossbred lambs (initial BW 23 +/- 3.9 kg) were used in a 2 x 2 factorial design experiment to determine the effects of DM and CP intake on lamb performance and weight and accretion rates of visceral organs during two periods of growth, divided at 36 kg live weight. There were 10 lambs per replicate and two replicate pens per treatment. Dry matter intake was 100 or 85% of ad libitum, and protein intake was 100 (normal) or 125% (high) of the calculated NRC (1985) requirement. Over both periods, lambs allowed ad libitum access to feed had greater (P < .05) ADG, rumen/reticulum, large intestine, and liver weights and faster accretion rates than lambs fed at 85% of ad libitum; however, there were no differences (P = .87) in feed efficiency. For the total trial, lambs fed high protein had greater (P < .01) DMI, ADG, liver and kidney weight and accretion rates, and increased (P < .01) feed efficiency during period 1 compared with lambs fed normal protein concentrations. Diets containing high concentrations of dietary protein resulted in greater DMI and ADG throughout the feeding period compared with diets formulated at NRC (1985) recommended concentrations, indicating that NRC (1985) protein recommendations may limit lamb performance. Restricted feeding resulted in reduced visceral organ mass compared with offering feed for ad libitum consumption. Restricted feeding increased efficiency of feed utilization for gain, in part, through reductions in visceral organ mass.

Animals↗

PubMed1973

The effect of dietary crude protein level on intestinal and cecal coccidiosis in chicken.

The effect of interaction of crude protein level in the diet and coccidiosis of the cecum and small intestine of chicks was investigated. A total of 390 day-old chicks were divided in 36 groups of ten and six groups of five chicks each. Twelve groups of ten and two groups of six chicks each were fed one of the three diets based on dietary crude protein level (16%, 20% and 24%). All diets contained an equal energy concentration. The chicks were on the appropriate diet for 15 days prior to infection. Each group was then subjected to one of the three treatments (a) control, (b) a single dose infection with 100,000 oocysts of Eimeria acervulina and (c) a single dose infection with 10,000 oocysts of Eimeria tenella. On the eighth day post infection all surviving E. tenella infected chicks and two replicates per dietary treatment of control and E. acervulina infected chicks were killed. An increase in dietary crude protein led to a linear (P<0.01) increase in daily gains and feed efficiency but did not affect feed consumption of chicks during one to 15 days pre-infection. Coccidiosis caused a reduction in daily gain, feed consumption and efficiency of feed utilization, the effect being more severe in E. tenella infection. The effect of dietary crude protein was protective against weight reduction. Chicks infected with E. tenella fed 24% crude protein had a higher (P<0.01) mortality rate than those fed on 16% or 20% crude protein level. The oocyst production by E. acervulina infected chicks was also higher (P<0.01) at the 24% crude protein level. The E. acervulina infected chicks exhibited compensatory growth during the eight to 14 days post infection. The compensatory growth was superior at the higher crude protein levels. The mechanism of compensatory growth is discussed.

Animals↗

PubMed2000

Effects of hydrolyzed spray dried red blood cells in milk replacer on calf intake, body weight gain, and efficiency.

An alternative protein ingredient based on spray-dried, hydrolyzed red blood cells was evaluated in calf milk replacers. Two experiments were conducted to determine the value of the ingredient on intake, growth, and feed efficiency in dairy calves. In experiment 1, Holstein bull calves (n = 120) were fed calf milk replacer containing 0, 11, 22, or 43% of crude protein as spray dried hydrolyzed red blood cells. Calves were fed 454 g/d of experimental milk replacer reconstituted to 12% dry matter plus a conventional calf starter for 28 d. Body weight gain, intake of milk replacer and calf starter, feed efficiency, fecal scores, and days scouring were unaffected by source of protein. In experiment 2, Holstein calves (n = 69) at the University of Minnesota, Crookston and Waseca were fed milk replacer containing 0, 22, or 43% of crude protein as spray dried hydrolyzed red blood cells. Calves were fed 454 g/d of experimental milk replacer reconstituted to 12% dry matter plus a conventional calf starter containing 0 or 25% alfalfa meal for 35 d. No calves died during the study. Body weight gain, feed efficiency, intake of calf starter and milk replacer, fecal scores, and days scouring were unaffected by increasing hydrolyzed red blood cells in milk replacer. Similar performance of all calves indicated that spray dried hydrolyzed red blood cells can replace up to 43% of crude protein from whey protein concentrate without detrimental effects on animal performance.

Animal Feed↗

PubMed1975

Physiological effects of 1,3-butanediol fed to cattle.

In four trials with growing cattle we observed effects of 1,3-butanediol on rumen fermentation end products, blood components, growth rates, feed efficiency, and body composition. Diets A and C contained 80% grain: 20% alfalfa pellets and 40% grain: 60% alfalfa pellets; in diets B and D, 1,3-butanediol replaced 4% of diets A and C. Feeding 4% 1,3-butanediol caused no significant differences in rumen pH, volatile fatty acid ratios, blood glucose, or blood ketones. Cattle fed 4% 1,3-butanediol had rates of gain and feed efficiency equivalent to and often better than cattle fed the same diet without butanediol. Body composition was not affected by feeding 4% 1,3-butanediol. Results indicate 4% 1,3-butanediol can be fed to cattle without adverse physiological effects and may improve performance. When 6% or more 1,3-butanediol was fed, blood ketones were elevated considerably, animals were hyperactive, gained less weight, and feed efficiency was lower.

Acetoacetates↗

PubMed1982

Effects of dietary protein quantity and quality on the growth of dogs and rats.

The growth of immature beagle dogs and weanling rats fed dietary protein concentrations between 0 and 20% were investigated. With lactalbumin as the protein source, 8- to 10-week-old dogs exhibited optimal growth when the diet supplied between 15 and 20% protein, whereas in older growing dogs (13-17 weeks) maximum growth and feed efficiency occurred with 11.7% dietary protein. Growth and feed efficiency of weanling rats were calculated to be optimal at 11.5% dietary protein. The protein efficiency ratio (PER) calculated during 14 days of feeding a 10% lactalbumin diet was 3.14 for 8- and 10-week-old dogs, 3.42 for 13- to 17-week-old dogs and 3.92 for weanling rats. Subsequent experiments examined the utilization of casein, soy isolate and wheat gluten by immature dogs and weanling rats. When diets contained 10% protein the adjusted PERs of casein, soy and wheat gluten were 2.50, 1.26 and -0.43 for the dog and 2.50, 1.60 and 0.34 for the rat, respectively. At 7.5% protein the adjusted PERs of casein, soy and wheat gluten were 2.50, 1.19 and -3.21 for the dog and 2.50, 1.44 and 0.29 for the rat. Thus, the rat can be a useful model for examining the quality of proteins fed to dogs. However, by using the rat one may overestimate the value of some low quality proteins.

Animals↗

PubMed1982

Effect of dietary alfalfa on zearalenone toxicity and metabolism in rats and swine.

Experiments were conducted with rats and swine to determine the potential of dietary alfalfa as a treatment for zearalenone (Z) toxicosis. Ninety-six female weanling Wistar rats were fed a casein-based semipurified diet containing 0, 15 or 25% alfalfa and 0 or 250 micrograms Z/g feed. Exposure to Z for 14 d resulted in reduced growth, feed consumption and feed efficiency as well as kidney and liver enlargement and reduced activity of 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD). Z had no effect on uterine weight. Including alfalfa in these diets reduced the inhibitory effects of Z on growth and feed consumption, minimized Z-induced liver enlargement and increased hepatic 3 alpha-HSD activity. Dietary alfalfa also reduced concentrations of residual Z and zearalenols (Zl) in liver. In a second experiment, 108 Yorkshire gilts weighing 8 to 11 kg were fed diets containing 0, 15 or 25% alfalfa and 0, 10, 20 or 40 micrograms Z/g feed for 4 wk. Z caused uterine enlargement when fed as low as 10 micrograms/g feed, although no effects were seen in growth rate, feed consumption or feed efficiency. Alfalfa decreased uterine enlargement (P less than .05), but caused a depression in feed efficiency (P less than .05). Hepatic 3 alpha-HSD activity was five times lower in swine than in rats, although activity still tended to decrease with Z and increase with alfalfa feeding. Residues of Z and Zl in pig liver indicated species differences in the metabolism of Z. These studies show that dietary alfalfa promotes Z metabolism in rats and that this feedstuff may also be useful for treating Z toxicosis in livestock.

3-Hydroxysteroid Dehydrogenases↗

PubMed1990

Effect of aluminum on performance and mineral metabolism in young chicks and laying hens.

This study was performed to determine the long-term effects of dietary aluminum on egg production and reproductive parameters in the mature laying hen and on growth rate and feed efficiency in young chicks. The diets used in these studies were adequate in phosphorus and other essential nutrients. Aluminum added to constitute 0.30% of the diet severely depressed growth and reduced feed efficiency, bone ash and plasma phosphorus in male Ross x Leghorn chicks. At the same time, 0.15% added aluminum mildly depressed growth, feed efficiency and bone ash but had no effect on plasma phosphorus levels. The reduction in bone ash was relatively mild, and no clinical signs of rickets were observed. In laying hens, diets containing 0.15% added aluminum did not affect egg production, but 0.30% added aluminum reduced production significantly. Long-term exposure to aluminum increased percent shell in both groups receiving aluminum, whereas egg weight remained similar to that in controls. There were no changes in hatchability or bone ash associated with dietary aluminum. Although dietary aluminum influenced bone aluminum content, egg aluminum content was not affected. These studies indicate that dietary aluminum interferes with systems in addition to phosphorus metabolism.

Aluminum↗

PubMed1990

Comparative effects of dietary tannins in ducks, chicks, and rats.

Studies were conducted to compare the effects of feeding high-tannin sorghum (HTS)- and low-tannin sorghum (LTS)-based diets suboptimal in protein to ducks, chicks, and rats. In the first series of experiments, Savanna (HTS) depressed both growth and feed efficiency of chicks and rats when compared with animals fed RS-610 (LTS). In contrast, ducks fed Savanna-based diets exhibited greater weight gains, but poorer feed efficiency values than birds fed RS-610. In a second series of experiments, Pioneer 8333 (LTS) and DeKalb BR-64 (HTS) sorghum-soybean meal diets were fed to chicks, ducks, and rats. As compared with animals fed 8333, BR-64 depressed both growth and feed efficiency of chicks and rats, but did not significantly affect either parameter in ducks. The lack of effect of HTS on duck growth may have been due to the formation of tannin-protein complexes upon exposure of the ground grain to water. This theory was based on the following observations: 1) ducks consumed water immediately after eating to facilitate swallowing the dry-mash diet; 2) a large amount of feed was deposited on the bottom of each water trough and subsequently consumed; and 3) ground HTS, which had been soaked for 4 h, had virtually no assayable tannin after drying. However, despite the marked reduction in assayable tannin content of treated HTS versus HTS that was dried only, the former material still depressed growth and feed conversion of rats. Thus, the lack of a growth-depressing effect of sorghum tannins in ducks fed dry-mash diets is both unique and unexplained.

Analysis of Variance↗

PubMed1989

Effects of dietary protein and added fat on turkeys varying in strain, sex, and age. 1. Live characteristics.

An experiment was conducted to determine the effects of dietary protein and added fat on body weight, feed consumption, and feed efficiency of male and female Nicholas Large White (N), Jaindl Large White (JL), and Jaindl Medium White (JM) turkeys at various ages. At 8 wk of age, 162 males and 288 females from each strain were divided equally into six pens of males and six pens of females per strain. Each of 6 pelleted diets containing standard or high protein and 0, 5, or 10% added fat was fed to one pen of each sex and strain of turkeys. At 20 wk of age, N, JL, and JM males weighed 14.77, 11.56, and 9.00 kg, respectively, and females weighed 8.97, 7.49, and 5.75 kg, respectively. At 28 wk of age, N, JL, and JM males weighed 18.32, 15.10, and 11.65 kg, respectively, and females weighed 10.35, 9.12, and 7.04 kg, respectively. The feeding of diets containing 10% rather than 0% added fat from 8 to 20 wk of age decreased feed consumption 11.1 and 13.1% and increased feed efficiency 16.3 and 16.4% in males and females, respectively. Feeding high protein diets significantly increased body weight gains. The apparent smaller increase than previously experienced in feed efficiency from dietary added fat may be associated with the use of pelleted feed in this experiment.

Age Factors↗

PubMed1985

Amelioration of the adverse effect of a gastrointestinal challenge with Salmonella enteritidis on weanling rats by a yogurt diet.

The response of yogurt-fed rats and the corresponding unfermented milk-fed rats to an infectious gastrointestinal challenge has been compared. After 1 (2 trials), 7 (4 trials), 14 and 21 (1 trial each) days on freeze-dried milk or yogurt diets, the rats were inoculated intra-gastrically by intubation per os with 4.5 X 10(10) +/- 0.7 colony forming units (mean +/- SEM) of Salmonella enteritidis. Challenged and control rats were monitored during the 3 weeks post-inoculation for viability, weight gain, feed consumption, and feed efficiency. In general, challenged yogurt-fed rats exhibited significantly superior weight gain and feed efficiency (but not feed consumption) values in week 1 post-infection, but the differences were not significant in week 2 post-infection. Sick milk- and yogurt-fed rats convalesced in week 3. Pooled mortality data indicated that yogurt-fed rats survived better than milk-fed rats. Yogurt did not prevent salmonellosis per se but significantly reduced the mortality and weight gain deceleration.

Animals↗

PubMed1988

Estimates of genetic parameters and predicted selection responses for growth, fat and lean traits in mice.

Heritabilities (ĥ2) and genetic correlations (rG) were estimated by regression of offspring on sire in two replicate, unselected lines of mice. Traits were associated with growth, feed efficiency, fat deposition and lean tissue. The ĥ2 for growth traits ranged from .34 to .42, except for 3-wk body weight, which was only .05. The ĥ2 for feed efficiency was .28. Ranges in ĥ2 were .45 to .50 for fat deposition traits and .36 to .42 for lean tissue traits. The rG involving 3-wk to 6-wk feed efficiency with hind carcass and fat measurements at 12 wk were small. Antagonisms were found between the sign of rG and the direction of usual breeding goals for pairs of traits (e.g., rG greater than 0 between fat deposition and hind carcass weight and rG less than 0 between hind carcass as a percentage of body weight and body weight). Selection indexes were developed to counteract these antagonisms. Modified selection indexes were compared where responses in individual traits rather than the aggregate breeding value were of major importance. The aggregate breeding values and selection indexes included: 1) epididymal fat pad weight and body weight, 2) hind carcass weight and body weight, or 3) all three traits. Economic weights in retrospect were calculated for the modified selection indexes. In some cases, expected correlated responses in component traits were not influenced greatly over a wide range of ratios of economic weights, but in other cases the component traits changed sharply over a narrow range of ratios.

Adipose Tissue↗

PubMed1997

Zinc repletion with organic or inorganic forms of zinc and protein turnover in marginally zinc-deficient calves.

We conducted two experiments using marginally Zn-deficient (-Zn) calves to determine which supplemental chemical form of Zn would most rapidly reverse certain Zn deficiency signs and to determine whether a change in protein turnover had occurred in Zn deficiency. In Exp. 1, 40 crossbred beef heifers were allocated by BW to four groups. The control group received 23 mg Zn/kg diet DM from ZnSO4 supplemented to the -Zn diet (17 mg Zn/kg diet DM). The three other groups received the -Zn diet. After 21 d, based on a decreased (P < .05) feed efficiency, they were deemed -Zn. Cell-mediated immune (CMI) response to phytohemagglutinin (PHA) was reduced (P < .05) but plasma and liver Zn were unaffected in the -Zn calves. Zinc was repleted by feeding iso-Zn amounts (23 mg Zn/kg diet DM) from Zn lysine, Zn methionine, or ZnSO4. At 8 h after injection of PHA, control CMI response values were similar to Zn Methionine, and Zn lysine was lower (P < .05). In Exp. 2, 10 Holstein steers were allocated by BW to two groups. One group received the -Zn diet, and the other received the +Zn diet. Urine collections were obtained from both groups of calves when the -Zn calves showed a decrease (P < .05) in feed efficiency relative to the controls and when they were repleted with 23 mg Zn/kg diet DM from ZnSO4 and their feed efficiency had returned to that of the controls. Urinary 3-methylhistidine indicated that -Zn calves had less (P < .05) daily protein degradation than the controls. Refeeding Zn to the -Zn group did not change BW or daily protein degradation. Results indicated that a marginal Zn deficiency decreased fractional accretion rate, increased (P < .05) urine excretion, and tended to increase (P < .19) Na and decrease (P < .12) K concentrations in the urine.

Animals↗

PubMed1984

Effects of age at slaughter and feeding regime on slaughter weight and carcass composition in mice.

Mice from three outbred stocks (PGH, J, and SWO) were fed either pelleted feed from overhead hoppers or ground feed from jars, from weaning at 21 days old to slaughter at 42, 49 or 56 days old. Live weights, weights of carcasses before and after extraction of carcass moisture and fat, and feed consumption were recorded. The PGH stock gained more in dry lean tissue and deposited less fat, and had a greater feed efficiency, compared to either of the other stocks. Males gained more than females, in both dry lean tissue and fat; females had a higher proportion of lean tissue and a greater feed efficiency. Increases in live weight between 49 and 56 days of age were mainly increases in fat content, especially in the offal portion of the body. Jar feeding restricted feed intake and reduced live weight gains. The reduction, however, was principally in fat deposition; feed efficiency was also greater for jar fed mice. It was found that the amount of lean tissue could be accurately predicted from carcass weight and carcass moisture measurements. It may be possible to estimate lean tissue accurately without employing the expensive and time consuming process of either extraction.

Adipose Tissue↗

PubMed1997

Effects of programmed gain strategies on performance and carcass characteristics of steers.

In Trial 1, 161 Angus x Simmental crossbred steers (initial BW 305 +/- 1.0 kg) were used in a completely randomized design experiment to determine the effects of intake restriction and programmed gain on cattle performance and carcass composition and characteristics. Five feeding systems were tested using step-wise increases in programmed intake level. Initially steers were fed to gain 1.13 kg/d. Intake was then increased to achieve a gain of 1.36 kg/d. At the end of the feeding period, steers had ad libitum access to feed. Duration of intake restriction and the period of unrestricted intake was varied. Feeding steers at restricted intakes and then increasing daily gain by increasing feed intake using four different schedules all reduced (P < .05) daily feed intake and total feed intake compared with providing ad libitum access to feed throughout the trial. Furthermore, daily feed efficiency was increased (P < .05) by two of the feeding systems compared with offering ad libitum access to feed throughout the trial. The feeding system used did not affect (P > .10) quality grade of the carcasses. In Trial 2, 77 individually penned Angus x Simmental crossbred steers (initial BW 273 +/- 1.2 kg) were used to determine the effects of various feed intake restriction systems. For systems 1 through 4, multiple periods of restriction and realimentation were investigated; the duration and magnitude of restriction were varied. Feed intake was not restricted for steers in system 5. The feed restriction systems used in this experiment did not result in decreased total feed intake or changes in carcass composition as compared with offering ad libitum access to feed. Reducing total energy intake seems to be a prerequisite to altering feed efficiency of steers in limit-feeding systems.

Animals↗

PubMed1993

Effects of excess methionine or lysine for broilers fed a corn-soybean meal diet.

Three experiments were conducted to examine the consequences of over-supplementing DL-Met or L-Lys (as L-Lys.HCl) in diets for chicks fed a corn-soybean meal diet (23% CP, 3,200 kcal MEn/kg, .2% supplemental Met) during 1 to 3 wk posthatching. New Hampshire x Columbian male chicks were used in Experiments 1 and 2 and Hubbard x Hubbard males were employed in Experiment 3. The basal diet was supplemented with .5, 1.0, 2.0, or 4.0% DL-Met, or .4, .8, 1.6, or 3.2% L-Lys in Experiment 1. Weight gain, feed intake, and feed efficiency decreased linearly at supplemental levels of DL-Met between 1.0 and 4.0%. Weight gain of chicks fed diets with supplemental L-Lys levels greater than 1.6% was less than that of chicks fed the basal diet, but feed efficiency was not significantly affected. Adding K2CO3 to the diets containing 1.6 or 3.2% added L-Lys did not improve performance. Experiment 2 evaluated the effect of 1) adding 1.0% Gly or 1.0% L-Thr to the diet supplemented with 2.0% DL-Met; and 2) adding NaHCO3 to the high-Lys diets in order to buffer the excess chloride provided by L-Lys.HCl. Addition of these amino acids or buffer ameliorated but did not totally correct the negative effects of excess Met or Lys. Experiment 3 examined the tolerance of commercial broilers to supplemental DL-Met or L-Lys levels of .5 or 1.0%. Weight gain and feed efficiency were not affected by these excesses, but feed intake was reduced at the 1.0% level of inclusion of either amino acid.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1992

Research note: effect of 2,4-dinitrophenol on growth and body composition of broilers.

The effects of 2,4-dinitrophenol (DNP) on growth, feed efficiency, fattening, and mitochondrial functions of liver and skeletal muscle were studied in broilers. The DNP was added at levels of 100, 200, and 400 mg/kg of diet. Feed intake was not changed with administration of DNP except at 100 mg/kg of diet. Body weight was significantly decreased by administration of DNP at 400 mg/kg of diet compared with those at 0 and 100 mg/kg of diet. Feed efficiency was significantly reduced by administration of DNP at 400 mg/kg of diet. Abdominal fat and carcass fat contents, expressed either as absolute values or relative percentages of body weight, were significantly decreased with increasing dietary DNP concentration above 200 mg/kg of diet. These results showed that administration of DNP reduced body fat, which may be associated with the change in feed efficiency. No reduction in adenosine triphosphate:oxygen ratio with increasing DNP concentration was observed in hepatic and skeletal muscle mitochondria isolated from broilers fed experimental diets containing DNP.

2,4-Dinitrophenol↗