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PubMed1997

The effect of grain source and grain processing on performance of feedlot cattle: a review.

Effects of grain species and grain processing method on DMI, rate and efficiency of gain, and feeding value for cattle fed high concentrate diets were appraised by statistically compiling results from 605 comparisons from feeding trials published in North American journals and experiment station bulletins since 1974. Metabolizable energy (ME) values for each grain and processing method were calculated by quadratic procedures from DMI and animal performance. Averaged across processing methods, ME values for corn, milo, and wheat grain (3.40, 3.22, and 3.46 Mcal/kg DM) fell within 9% of ME estimates from NRC (1996) for beef cattle. In contrast, ME values for barley and oats grain (3.55 and 3.46 Mcal/kg DM) were 24% and 17% greater than NRC (1996) estimates. Compared with the dry rolled forms, high moisture corn and milo resulted in lower ADG and DMI. Compared with dry rolling, either steam rolling or flaking of corn, milo, and wheat decreased DMI without decreasing ADG and improved feed efficiency by 10, 15, and 10%, respectively. Compared with dry rolled grain, steam flaking increased (P < .05) body weight-adjusted ME of corn and milo grain by 15 and 21%, respectively; body weight-adjusted ME for whole corn was 9% greater (P < .05) than for rolled corn grain. Steam flaking was surprisingly effective (13%) at increasing (P < .05) the body weight-adjusted ME of wheat, but steam flaking failed to increase the ME of barley and oats. Higher moisture content of high-moisture corn decreased dry matter intake without depressing ADG and improved efficiency and increased ME of the grain. Compared with steam flakes of moderate thinness, processing milo or barley to a very thin flake tended to reduce ADG and failed to improve feed efficiency. The ideal roughage source and roughage moisture content for maximum ME and ADG varied with grain processing method. Feeding corn silage rather than alfalfa and wet rather than dry roughage depressed (P < .01) ADG of cattle and reduced (P < .01) body weight-adjusted ME of cattle fed high-moisture corn grain but tended to increase both with steam-flaked corn or wheat.

Animals↗

PubMed1988

Response of growing turkeys to dietary fat.

Growth, feed efficiency, and carcass fat were evaluated in turkeys fed diets in which added fat varied, holding energy or the calories:protein ratio constant. In the 1 to 3-wk-old turkey, growth and feed efficiency increased with dietary energy, but did not change significantly when fat was added isocalorically. The 12 to 14-wk-old turkey responded with improved growth and feed efficiency when dietary fat was added either isocalorically or with increasing energy density. However, the response to the isocaloric fat addition was smaller in magnitude than the response when fat was added without calorie adjustment. No difference could be detected in 12 to 15-wk-old turkeys in the performance response to tallow and soybean oil. Carcass fat deposition generally increased with dietary fat supplementation, regardless of the caloric change. The results suggest that in the midterm of development of the growing turkey, dietary fat per se affects growth, feed efficiency, and carcass fat. Growth and feed efficiency responses to nutrient density occur in both young and older birds.

Adipose Tissue↗

PubMed1991

Biological utilisation of pearl millet flour fermented with yeasts and lactobacilli.

Mixed culture fermentation of pearl millet flour with Saccharomyces diastaticus, Saccharomyces cerevisiae, Lactobacillus brevis and Lactobacillus fermentum brought about an improvement in its biological utilisation in rats. Protein efficiency ratio, feed efficiency ratio, apparent protein digestibility, true protein digestibility, net protein utilisation, net protein retention, protein retention efficiency and utilisable protein values in case of pure culture fermented pearl millet four were higher than the control. Feeding of the fermented products did not bring about physiological, histopathological and haematological changes in rats. Chapaties and cutlets prepared from the fermented products were organoleptically acceptable.

Animals↗

PubMed1985

Varying fat and protein in diets of growing large white turkeys.

Two series of three consecutive 4-week experiments with a total of 1,370 Large White turkeys between 8 and 20 weeks of age were conducted to determine the effects of varying levels of dietary fat and protein on body weight gain and feed efficiency. Diets containing 0, 5, and 10% added fat and 18, 20, 22, and 24% protein in a 3 X 4 factorial were each fed to a total of three pens of males and three pens of females. At the end of each 4-week period, the turkeys were rerandomized to form 12 new equivalent groups, and similar diets with 2% less protein were fed. As part of this study, two fats, varying in fatty acid composition, were also compared but found not to affect significantly body weight gain or feed efficiency. Interaction effects of fat and protein on body weight gain, feed consumption, or feed efficiency were not significant. Body weight gain increased .5, .6, and 1.1%, feed consumption decreased 1.1, 1.0, and .9%, and feed efficiency increased 1.7, 1.8, and 2.2% for each 1% added fat during the 8 to 12-, 12 to 16-, and 16 to 20-week periods, respectively. The greater-than-expected increase in feed efficiency from added fat to diets of older turkeys is postulated to be due to stimulated feed consumption and body weight gain rather than to an extra caloric content of fat per se.

Aging↗

PubMed1986

Weight gain, feed conversion efficiency and plasma free lysine as response criteria in evaluating supplements of lysine plus threonine and lysine plus tryptophan to deficient diets for rats.

Two experiments were conducted on growing male SPF-rats to compare weight gain, feed conversion efficiency and plasma free lysine concentration as response criteria in evaluating adequacy of lysine plus threonine and lysine plus tryptophan supplements to the deficient diets. Two basal semisynthetic diets were prepared limiting in lysine and threonine (Expt. 1) and lysine and tryptophan (Expt. 2). The addition of graded supplements to the basal diets of L-lysine X HCl alone (0.2; 0.4; 0.6; 0.8 and 1.0% of diet) induced imbalance of amino acids resulting in low level of daily weight gain and feed conversion efficiency. Plasma free lysine concentration started to grow linearly from the first supplement of L-lysine X HCl. If rats were fed the diets containing identical supplements of L-lysine X HCl in combination with two supplements of L-threonine (0.2 and 0.4% of diet, Expt. 1) or L-tryptophan (0.05 and 0.1% of diet, Expt. 2), plasma free lysine started to increase before supplements of amino acids were adequate to support maximum weight gain and feed conversion efficiency. this difference in response seems to be caused by different feeding regiment during the growth period of the experiments (ad libitum) and training period prior to blood sampling (feeding twice daily).

Animal Feed↗

PubMed1981

Extrahypothalamic mediation of changes in feeding behavior induced by growth of Walker 256 carcinosarcoma in rats.

Feeding efficiency (amount of food ingested per unit of feeding activity) was chronically depressed in male Sprague-Dawley rats recovered from the acute aphagia or hypophagia of lateral hypothalamic damage. The extent of depression varied with the severity of the acute feeding response to hypothalamic damage. Growth of Walker 256 carcinosarcoma in intact rats increased feeding efficiency. Chronic lateral hypothalamic damage did not significantly attenuate tumor-induced increase in feeding efficiency but lowered the initial and maximum efficiency levels. Growth of the tumor-bearing host was depressed by residual lateral hypothalamic damage, but this depression was not related to the severity of the acute feeding response to damage.

Animals↗

PubMed1991

Evaluation of the effect of fumaric acid and sodium bicarbonate addition on performance of starter pigs fed diets of different types.

Three growth experiments were conducted to assess the effect of fumaric acid (FA) supplementation on the performance of pigs fed different types of diets. These 4-wk experiments involved 550 crossbred pigs weaned at 30 +/- 3 d of age. Pigs in Exp. 1 were fed either a simple corn-soybean meal (SBM) diet or a 75% corn-SBM, 25% dried skim milk (DSM) diet. Zero, 2, or 3% FA were added to the diets to create a 2 x 3 factorial arrangement of treatments. Supplementing diets with DSM improved gain (P less than .05) and gain/feed (P less than .001). Fumaric acid addition improved efficiency of feed utilization (P less than .01). Experiment 2 was conducted to evaluate the effect of protein source (casein or soy protein concentrate [SPC]) on the response to 3% FA. Sodium bicarbonate (BCB; 2.75%) was added to one diet containing casein and FA to negate the effect of FA on growth performance. Addition of FA improved gain and feed efficiency (P less than .05) during the first 2 wk.(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗

PubMed1995

Growth and intestinal morphology of male turkeys as influenced by dietary supplementation of amylase and xylanase.

Three diets, a control and two diets supplemented with an enzyme cocktail premix containing either amylase or xylanase, were each fed to 100 male poults (10 replicates of 10 poults per pen) from 0 to 5 wk of age to observe the effects upon body weight gain, feed intake, and feed efficiency. The amylase-supplemented diet significantly increased feed efficiency through the first 2 wk and significantly increased body weight gain and feed intake through the first 3 wk. Xylanase supplementation did not improve growth or feed efficiency over the control. Mean villus length within the jejunum and ileum was significantly increased at 2 and 3 wk of age by dietary supplementation of amylase when compared with the control and xylanase diets. These findings suggest that the increased growth associated with the amylase diet during 0 to 3 wk can, in part, be explained by the increase in absorptive surface area, allowing for increased digestion of available nutrients coupled with increased enzyme activity for carbohydrate degradation from the supplemental enzymes.

Amylases↗

PubMed1995

Nutritional value for growing turkeys of corn of light test weight.

An experiment was conducted to determine the relationship between test weight of corn and growth, efficiency of feed utilization, nutrient retention, and carcass composition of young turkeys. The MEn values of corn were also measured. Two samples of corn differing substantially in test weight were fed to male turkey poults (Nicholas Large White) from 1 to 20 d of age. The test weights of the light-weight corn and the normal-weight corn were 55 kg/hL (43 lb/bu) and 70 kg/hL (54 lb/bu), respectively. The light-weight corn was lower in crude protein concentration (6.63%) than the normal-weight corn (8.53%). The determined MEn of the corn samples did not differ (3.22 vs 3.25 kcal/g). The light-weight corn diet had modest adverse effects on growth and feed efficiency of poults during the 1 to 7 d after hatching. Poult carcass composition and retention of nitrogen and energy were not affected by the test weight of corn.

Animal Feed↗

PubMed1989

Effect of protein and(or) carbohydrate fractions of dried whey on performance and nutrient digestibility of early weaned pigs.

One hundred eighty 3-wk-old pigs (initial weight 4.8 kg) were utilized in a 35-d growth trial to determine the effects of the carbohydrate and(or) protein fraction of dried whey on pig performance. In addition, 30, 3-wk-old pigs (initial weight 4.9 kg) were used in two digestion trials to study the effects of the whey fraction on nutrient digestibility. Dietary treatments included a corn-soybean meal diet (control), control + 20% dried whey, control + 14.4% lactose, control + 2.1% lactalbumin, control + 14.4% lactose + 2.1% lactalbumin, and control + 8.4% whey protein concentrate. Pelleted diets containing equal lysine concentrations were fed. Lactose and lactalbumin were added at the same levels as provided by a 20% dried whey diet. Pigs fed diets containing milk products exhibited superior (P less than .05) ADG and efficiency of feed utilization and greater (P less than .05) apparent digestibilities for DM, energy and N compared with pigs fed the control diet. Including either lactose or lactalbumin in the diet for the early weaned pig resulted in similar gain, feed efficiency and nutrient digestibility. These results indicate that both the carbohydrate (lactose) and protein (lactalbumin) fractions of dried whey are important in explaining the beneficial response to dried whey elicited in the weanling pig.

Animal Feed↗

PubMed1975

Relative utilization of serine and glycine by chicks.

Studies were conducted on the relative utilizaiton of glycine and serine by chicks fed basal crystalline amino acid diets devoid of these amino acids. The crystalline amino acid mixture was fed at one and three times the requirement levels, thereby stimulating uric acid synthesis at differing rates. In addition, 5 per cent L-glutamine replaced L-glutamic acid on an isonitrogenous basis in three diets containing normal levels of amino acids in the second study. Chicks fed diets devoid of glycine and serine grew less rapidly and less efficiently than chicks fed diets containing either serine or glycine plus serine. These decreases were roughly the same whether the diet contained normal or high levels of amino acids. Serine was as efficient as glycine in supporting chick growth and feed efficiency regardless of whether diets containing normal or high levels of amino acids were fed. Chicks fed diets containing high levels of amino acids grew approximately 81 per cent as rapidly, but 24 per cent more efficiently, than chicks fed normal levels of amino acids, and excreted approximately twice the amount of uric acid per gram of nitrogen consumed. In spite of increased uric acid excretion by chicks fed the high amino acid diets, the dietary void in glycine and serine was no more detrimental to chick growth or feed efficiency than that noted when normal levels of amino acids were fed. Feeding 5 per cent L-glutamine rather than L-glutamic acid in the diet containing normal levels of amino acids had little effect on weight gain, feed efficiency or uric acid excretion. The absence of cystine from the amino acid mixture used in the third study did not have a marked influence on the relative utilization of glycine and serine by the chick.

Animal Feed↗

PubMed1979

A comparison of the Nigerian indigenous fowl with White Rock under conditions of disease and nutritional stress.

Equal numbers of day old White Rock and Nigerian indigenous male chicks were reared to 10 weeks of age under 4 variables consisting of 2 dietary regimes and 2 regimes of immunity (natural versus vaccinal) to Newcastle disease challenge. Although White Rock grew significantly faster, ate more food and tended to be more efficient in feed utilisation than the indigenous chicks, the mortality of the latter was significantly lower. Growth rate and feed intake were significantly greater, feed efficiency better and prechallenge mortality lower in birds fed on the higher crude protein diet. Prechallenge mortality was significantly lower in birds that had been vaccinated against Newcastle disease.

Animals↗

PubMed2006

Behavioral responses of a generalist mammalian folivore to the physiological constraints of a chemically defended diet.

Mammalian herbivores, particularly browsers and folivores, encounter and consume a range of plant chemical defenses [plant secondary metabolites (PSMs)] on a regular basis. The physiological regulation of PSM ingestion and the resulting behavioral responses of mammalian herbivores directly affect their feeding decisions and the subsequent foraging strategies that they adopt. Generalist mammalian herbivores are hypothesized to consume a generalized diet because of physiological limitations of their detoxification systems. The consumption of a generalized diet is proposed to enable toxin (PSM) dilution through the use of multiple detoxification pathways. We tested the predictions of the detoxification-limitation hypothesis by offering two chemically different plant species, Eucalyptus regnans and E. globulus, to a generalist mammalian folivore, the common brushtail possum (Trichosurus vulpecula), as single- and mixed-species diets. By feeding more efficiently, brushtail possums benefited more, through increased intake, on the mixed-species diet than on either of the single-species diets. We argue that frequently switching between chemically diverse foliage reduces the physiological constraints imposed by a PSM-rich diet and enables more efficient feeding. The behavioral responses of brushtail possums were consistent with the proposed physiological constraints of a chemically defended diet, offering support for predictions of the detoxification-limitation hypothesis. We suggest that feeding behavior of herbivores may be a useful indicator of the physiological constraints imposed by a chemically defended diet.

Animals↗

PubMed1996

Metabolic and endocrine changes induced by chronic heat exposure in broiler chickens: growth performance, body composition and energy retention.

The present study was performed in order to investigate the effect of chronic heat exposure (32 degrees, constant) on growth, body composition and energy retention of broiler chickens in relation to age. At 2 and 4 weeks of age, fifty-four male Shaver broiler chickens were allocated to three treatments according to the following design: 22 degrees, ad lib. feeding (22AL); 32 degrees, ad lib. feeding (32AL); and 22 degrees, pair-feeding with the 32 degrees group (22PF). Ambient temperature was kept constant at either 22 or 32 degrees for 2 weeks. Heat exposure decreased feed intake by 14% between 2 and 4 weeks and by 24% between 4 and 6 weeks of age. Even with the same feed intake, chicks gained less weight at 32 degrees than at 22 degrees, 5.5% less in young chickens and 22% less in older ones. Hot environmental conditions thus resulted in decreased feed efficiency; the feed:gain ratio was 2.85 at 32 degrees compared with 2.06 at 22 degrees in 22AL birds for the period 4-6 weeks. Body composition appeared significantly affected by high ambient temperature. Feathering was reduced at 32 degrees in absolute weight but not as a proportion of body weight. Heat-exposed birds showed a decrease in body protein content, protein gain and protein retention. Group 32AL birds were fatter than the pair-fed (22PF) or ad lib.-fed (22AL) groups at 22 degrees. The percentage of energy retained as fat was 79 in heat-exposed chickens compared with 64 in the control groups. The energy retained as protein:energy retained as fat for groups maintained at 22 degrees (0.56) was twice that for those maintained at 32 degrees (0.28). These modifications should be investigated further in relation to metabolic and endocrinological changes.

Animals↗

PubMed2000

Oral feeding in premature infants: advantage of a self-paced milk flow.

An earlier study demonstrated that oral feeding of premature infants (<30 wk gestation) was enhanced when milk was delivered through a self-paced flow system. The aims of this study were to identify the principle(s) by which this occurred and to develop a practical method to implement the self-paced system in neonatal nurseries. Feeding performance, measured by overall transfer, duration of oral feedings, efficiency, and percentage of successful feedings, was assessed at three time periods, when infants were taking 1-2, 3-5, and 6-8 oral feedings/day. At each time period, infants were fed, sequentially and in a random order, with a self-paced system, a standard bottle, and a test bottle, the shape of which allowed the elimination of the internal hydrostatic pressure. In a second study, infants were similarly fed with the self-paced system and a vacuum-free bottle which eliminated both hydrostatic pressure and vacuum within the bottle. The duration of oral feedings, efficiency, and percentage of successful feedings were improved with the self-paced system as compared to the standard and test bottles. The results were similar in the comparison between the self-paced system and the vacuum-free bottle. Elimination of the vacuum build-up naturally occurring in bottles enhances the feeding performance of infants born <30 wk gestation as they are transitioned from tube to oral feeding. The vacuum-free bottle is a tool which caretakers can readily use in neonatal nurseries.

Equipment Design↗

PubMed1984

[Nitrogen metabolism in growing swine receiving a bacterial protein supplement (Alcaligenes eutrophus) instead of soybean meal].

In a balance trial with 10 pigs (mean body mass 50 kg) the influence of a bacterial protein supplement (Alcaligenes eutrophus) on N-metabolism was investigated. The bacteria were included into the diet at levels of 7 and 14% at the expense of extracted soyabean meal. Thus bacterial "pure protein" (bacterial non-nucleic acid N X X 6.25) amounted to 30 and 60% of the protein of the ration. Consuming 2 kg of feed dry matter per day the animals of the control group (I) and the experimental groups (II and III) ingested 48 g, 52 g and 55 g of total N respectively. The difference in N-intake is explained by the additional nucleic acid-N, amounting to 19,8% of total bacterial N. Daily weight gain (on average 1054 g) and feed conversion efficiency (feed ingested/weight gain; on average 1,9) were relatively improved at the highest dietary level of bacterial cell mass. Faecal N-excretion was increased significantly, whereas renal N-excretion remained unchanged. Mean apparent N-digestibility was 87,4% showing no significant difference between the experimental groups. N-balance values were noticibly increased following the intake of the bacterial protein supplement. The excretion of urinary urea-N was slightly reduced whereas 4-6 times as much allantoin-N was excreted when bacteria were fed. It is calculated that about 80% of the bacterial purines are renally excreted as allantoin and uric acid.

Alcaligenes↗

PubMed1987

Responses to excess dietary magnesium as affected by experimental Eimeria acervulina infection or by dietary ammonium chloride ingestion in the chick.

Three experiments were conducted to investigate the effect of experimental Eimeria acervulina infection on excess Mg ingestion in the chick and to investigate the effect of NH4Cl addition to the diet on the coccidiosis X Mg interaction. Two Mg sources were evaluated, MgO and MgSO4 X 7H2O. Gain, efficiency of feed utilization, bone ash percent (BAP), bone Ca and duodenal pH were lower in coccidiosis-infected chicks than in uninfected chicks. However, bone P and bone Mg levels were higher as a result of the coccidial infection. Bone Mg levels were higher and bone Ca levels and BAP were lower in chicks fed excess dietary Mg, either as the oxide or sulfate forms. Gain and feed efficiency of chicks fed excess Mg, as MgO but not as MgSO4 X 7H2O, were lower than in chicks fed the basal level of Mg. Coccidiosis X Mg interactions were observed in bone Mg and bone Ca concentration data; bone Mg uptake was greater when high dietary Mg and the coccidial infection were in combination. In some instances, a similar interactive effect was observed in bone Ca concentration data; bone Ca loss tended to be greater as a result of the combination of high dietary Mg and the coccidial infection.

Ammonium Chloride↗

PubMed2004

Evaluation of distillers dried grains with solubles as a feed ingredient for broilers.

Two experiments were conducted to evaluate the use of distillers dried grains with solubles (DDGS) from modern ethanol plants in broiler diets. Experiment 1 was a 2 x 2 factorial experiment with diets containing 2 levels of DDGS (0 and 15%) and 2 diet densities (high and low). The high- and low-density diets were formulated to contain 22% CP and 3,050 kcal MEn/kg and 20% CP and 3,000 kcal MEn/kg, respectively. Eight pens of 6 chicks were fed an experimental diet from 0 to 18 d of age. Weight gain and feed efficiency (gain:feed ratio) of the chicks receiving the high-density diets were (P < 0.05) better than those of chicks fed the low-density diets. However, within the 2 density levels there was no difference in performance of chicks fed diets with 0 or 15% DDGS. In experiment 2, 6 replications of 50 chicks were fed 1 of 4 dietary treatments for 42 d. The diets were formulated to be isocaloric and isonitrogenous and contained 0, 6, 12, or 18% DDGS. There was no significant difference in performance or carcass yield throughout the 42 d experiment except for a depression in BW gain and feed conversion when chicks were fed diets with 18% DDGS in the starter period. These studies indicate that DDGS from modern ethanol plants is an acceptable feed ingredient for broiler diets and can be safely used at 6% in the starter period and 12 to 15% in the grower and finisher periods.

Animal Feed↗