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D O Krause

Publications and source records attributed to D O Krause.

18 recordsLinked to original sources
PubMed2006

Efficacy of ionophores in cattle diets for mitigation of enteric methane.

Use of ionophores in cattle diets has been proposed as a strategy for mitigation of enteric CH4 emissions. Short- and long-term effects of feeding a single ionophore (monensin) or rotation of 2 ionophores (monensin and lasalocid) on enteric CH4 emissions were evaluated in 36 Angus yearling steers (328 +/- 24.9 kg of BW) over a 16-wk period. Steers were randomly assigned to 6 dietary treatments of 6 steers each. The 6 diets were low-concentrate without ionophore supplementation, low-concentrate with monensin supplementation, low-concentrate with a 2-wk rotation of monensin and lasalocid supplementation, high-concentrate without ionophore supplementation, high-concentrate with monensin supplementation, and high-concentrate with a 2-wk rotation of monensin and lasalocid supplementation. Daily enteric CH4 emissions, as measured using the SF(6) tracer gas technique, ranged from 54.7 to 369.3 L/steer daily. Supplementing ionophores decreased (P < 0.05) enteric CH4 emissions, expressed as liters per kilogram of DMI or percentage of GE intake, by 30% for the first 2 wk and by 27% for the first 4 wk, for cattle receiving the high-concentrate and low-concentrate diets, respectively. Cattle fed a rotation of ionophores did not (P > 0.05) exhibit a greater decrease and did not (P > 0.05) have a longer period of depressed enteric CH4 emissions compared with cattle receiving monensin only. Ionophore supplementation did not (P > 0.05) alter total ruminal fluid VFA concentration; however, the acetate:propionate ratio and ammonia-N concentration in ruminal fluid were decreased (P < 0.001) from the time that ionophores were introduced to the time they were removed from the diets. Both monensin and the rotation of monensin and lasalocid decreased (P < 0.001) total ciliate protozoal populations by 82.5% in the first 2 wk and by 76.8% in the first 4 wk during which they were supplemented in the high-concentrate and low-concentrate diets, respectively. Original ciliate protozoal populations were restored by the fourth and sixth week of supplementation when cattle were fed the high- or low-concentrate diets, respectively. No significant change was observed thereafter. These data suggest that the effects of ionophores on enteric CH(4) production are related to ciliate protozoal populations and that ciliate protozoal populations can adapt to the ionophores present in either low- or high-concentrate diets. Rotation of monensin and lasalocid did not (P > 0.05) prevent ciliate protozoal adaptation to ionophores.

Animal Feed↗
PubMed2006

Rumen lipopolysaccharide and inflammation during grain adaptation and subacute ruminal acidosis in steers.

Three rumen-fistulated Jersey steers were gradually adapted to a wheat-barley concentrate over a 4-wk period. Adaptation steps consisted of four 1-wk periods during which steers were fed diets with forage-to-concentrate (F:C) ratios of 100:0, 79:21, 59:41, and 39:61. The forage consisted of chopped hay (CH), and the concentrate consisted of pelleted concentrate containing 50% ground wheat and 50% ground barley. Steers were fed the all-forage diet ad libitum during wk 1. Feed offered in wk 2 to 4 was kept constant at the ad libitum intake during wk 1. On 2 d that were set 3 d apart during wk 5, subacute ruminal acidosis (SARA) was induced in the steers by feeding a diet with an F:C ratio of 24:76 by offering them 0.9 kg of CH at 0900 h followed by 2 meals of 3.0 kg each of wheat-barley pellets (WBP) at 1100 h and 1300 h and 0.9 kg of CH at 1700 h, to depress rumen pH for at least 3 h/d below 5.6. The average concentrate inclusion for the SARA induction diet was 76 +/- 10% DM. During stepwise adaptation, time with pH below 5.6 increased to an average of 121 min/d when the steers were consuming a diet containing 61% DM as WBP. Dietary inclusion of WBP at the rate of 76% DM induced SARA because the steers spent an average of 219 min/d with pH below 5.6. The free ruminal lipopolysaccharide (LPS) concentration increased from 6,310 endotoxin units (EU)/mL with the all-forage diet to 18,197 EU/mL with the 61% concentrate diet. The ruminal LPS concentration increased to 26,915 EU/mL when SARA was induced. Serum haptoglobin increased from 0.53 mg/mL when steers were on the all-forage diet to 1.90 mg/mL with the 61% concentrate diet and were not increased further by inducing SARA. The serum amyloid-A concentration was not affected by increasing dietary concentrate during stepwise adaptation to the concentrate, but increased from 71 to 163 microg/mL when SARA was induced. A gradual increase in dietary concentrate so that the F:C ratio decreased to 39:61 resulted in increased ruminal LPS concentrations. Subsequent induction of SARA further increased ruminal LPS and activated an inflammatory response.

Acidosis↗
PubMed2006

Screening of bacteria from the cattle gastrointestinal tract for inhibitory activity against enterohemorrhagic Escherichia coli O157:H7, O111:H-, and O26:H11.

A quick and reproducible microgel plate assay was adapted to screen bacteria from cattle gastrointestinal tracts for production of compounds inhibitory to the growth of three enterohemorrhagic Escherichia coli (EHEC) serotypes: O157:H7, O111:H-, and O26:H11. The inhibitory activity of 309 bacteria, isolated on several agar media, was assessed by a microgel assay performed in 96-well microtiter plates. Fifty-three isolates secreted inhibitory compounds with a molecular weight of less than 1,000. In 12 isolates, the inhibitory activity was attributable to compounds other than lactic or acetic acid. These compounds were highly heat tolerant, with varying sensitivity to digestion by proteolytic enzymes. The inhibitory isolates were identified as lactic acid-producing bacteria on the basis of a combination of analyses, including 16S-rDNA restriction fragment length polymorphisms, 16S-rDNA gene sequences, and fermentation end products. The lactic acid bacteria of ruminants may contain antibacterial compounds not yet described. Naturally occurring populations of lactic acid bacteria may have potential as probiotics, to reduce the carriage of EHEC in the gastrointestinal tract of ruminants.

Animals↗
PubMed2005

The diversity of Escherichia coli serotypes and biotypes in cattle faeces.

AIM: To study the diversity of commensal Escherichia coli populations shed in faeces of cattle fed on different diets. METHODS AND RESULTS: Thirty Brahman-cross steers were initially fed a high grain (80%) diet and then randomly allocated into three dietary treatment groups, fed 80% grain, roughage, or roughage + 50% molasses. Up to eight different E. coli isolates were selected from primary isolation plates of faecal samples from each animal. Fifty-two distinct serotypes, including nine different VTEC strains, were identified from a total of 474 E. coli isolates. Cattle fed a roughage + molasses diet had greater serotype diversity (30 serotypes identified) than cattle fed roughage or grain (21 and 17 serotypes identified respectively). Cluster analysis showed that serotypes isolated from cattle fed roughage and roughage + molasses diets were more closely associated than serotypes isolated from cattle fed grain. Resistance to one or more of 11 antimicrobial agents was detected among isolates from 20 different serotypes. Whilst only 2.3% of E. coli isolates produced enterohaemolysin, 25% were found to produce alpha-haemolysin. CONCLUSIONS: Diverse non-VTEC populations of E. coli serotypes are shed in cattle faeces and diet may affect population diversity. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides new information on the serotype diversity and phenotypic traits of predominant E. coli populations in cattle faeces, which could be sources of environmental contamination.

Animal Feed↗
PubMed2005

Effect of finishing diets on Escherichia coli populations and prevalence of enterohaemorrhagic E. coli virulence genes in cattle faeces.

AIM: To determine the effect of different carbohydrate-based finishing diets on fermentation characteristics and the shedding of Escherichia coli and enterohaemorrhagic E. coli (EHEC) virulence genes in cattle faeces. METHODS AND RESULTS: The size of faecal E. coli populations and fermentation characteristics were ascertained in three experiments where cattle were maintained on a range of finishing diets including high grain, roughage, and roughage + molasses (50%) diets. Increased E. coli numbers, decreased pH and enhanced butyrate and lactate fermentation pathways were associated with grain diets, whereas roughage and roughage + molasses diets resulted in decreased concentrations of ehxA, eaeA and stx(1) genes, this trend remaining at lairage. In one experiment, faecal E. coli numbers were significantly lower in animals fed roughage and roughage + molasses, than animals fed grain (4.5, 5.2 and 6.3 mean log10 g(-1) digesta respectively). In a second experiment, faecal E. coli numbers were 2 log lower in the roughage and roughage + molasses diets compared with grain-fed animals prior to lairage (5.6, 5.5 and 7.9 mean log10 g(-1) digesta respectively) this difference increasing to 2.5 log at lairage. CONCLUSIONS: The type of dietary carbohydrate has a significant effect on E. coli numbers and concentration of EHEC virulence genes in faeces of cattle. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides a better understanding of the impact finishing diet and commercial lairage management practices may have on the shedding of E. coli and EHEC virulence factors, thus reducing the risk of carcass contamination by EHEC.

Animal Feed↗
PubMed2005

Subacute ruminal acidosis induces ruminal lipopolysaccharide endotoxin release and triggers an inflammatory response.

Subacute ruminal acidosis (SARA) was induced in 3 rumen fistulated Jersey steers by offering them different combinations of wheat-barley pellets and chopped alfalfa hay. Steers were offered 4, 5, and 6 kg/d of pelleted concentrate and 6, 5, and 4 kg/d of chopped alfalfa hay for diets 1, 2, and 3, respectively, during 5-d treatment periods and were fed chopped alfalfa hay between treatment periods. Inducing SARA increased blood concentrations of haptoglobin and serum amyloid-A. Dry matter intake of concentrate and hay decreased from d 1 to 5 in each period. Subacute ruminal acidosis was induced in all steers during d 4 and 5 when concentrate was fed, with ruminal pH remaining below 5.6 for an average of 187 and 174 min/d on these days. Lipopolysaccharide concentration increased significantly during periods of grain feeding compared with times when only hay was fed. Inducing SARA by feeding wheat-barley pellets activated a systemic inflammatory response in the steers.

Acidosis↗
PubMed2003

Molecular characterization of the microbial species that colonize human ileal and colonic mucosa by using 16S rDNA sequence analysis.

AIM: The aim of this study was to characterize the bacterial community adhering to the mucosa of the terminal ileum, and proximal and distal colon of the human digestive tract. METHODS AND RESULTS: Pinch samples of the terminal ileum, proximal and distal colon were taken from a healthy 35-year-old, and a 68-year-old subject with mild diverticulosis. The 16S rDNA genes were amplified using a low number of PCR cycles, cloned, and sequenced. In total, 361 sequences were obtained comprising 70 operational taxonomic units (OTU), with a calculated coverage of 82.6%. Twenty-three per cent of OTU were common to the terminal ileum, proximal colon and distal colon, but 14% OTU were only found in the terminal ileum, and 43% were only associated with the proximal or distal colon. The most frequently represented clones were from the Clostridium group XIVa (24.7%), and the Bacteroidetes (Cytophaga-Flavobacteria-Bacteroides) cluster (27.7%). CONCLUSION: Comparison of 16S rDNA clone libraries of the hindgut across mammalian species confirms that the distribution of phylogenetic groups is similar irrespective of the host species. Lesser site-related differences within groups or clusters of organisms, are probable. SIGNIFICANCE AND IMPACT: This study provides further evidence of the distribution of the bacteria on the mucosal surfaces of the human hindgut. Data contribute to the benchmarking of the microbial composition of the human digestive tract.

Adult↗
PubMed2002

Transformation and expression of an anaerobic fungal xylanase in several strains of the rumen bacterium Butyrivibrio fibrisolvens.

AIMS: To obtain reliable transformation of a range of Butyrivibrio fibrisolvens strains and to express a Neocallimastix patriciarum xylanase gene in the recipients. METHODS AND RESULTS: Eight strains (H17c, E14, LP1309, LP1028, AR11a, OB156, LP210B and LP461A) of Bu. fibrisolvens were transformed by the Gram-positive vector pUB110. A xylanase expression/secretion cassette containing Bu. fibrisolvens promoter and signal peptide elements fused to catalytic domain II of the N. patriciarum xylanase A cDNA (xynANp) was inserted into pUB110 to create the plasmid pUBxynA. pUBxynA was used to transform seven of the Bu. fibrisolvens strains transformed by pUB110. In strain H17c pUBxynA, which produced native xylanase, 2.46 U mg-1 total xylanase activity was produced with 45% extracellular xylanase. In strain H17c pUMSX, 0.74 U mg-1 total xylanase activity was produced with 98% extracellular xylanase. H17c pUBxynA exhibited increased (28.7%) degradation of neutral detergent fibre compared with unmodified H17c; however, progressive loss of pUBxynA was observed in long-term cultivation. CONCLUSIONS: A stable transformation system was developed that was applicable for a range of Bu. fibrisolvens strains and high levels of expression of a recombinant xylanase were obtained in H17c which lead to increased fibre digestion. SIGNIFICANCE AND IMPACT OF THE STUDY: This stable transformation system with the accompanying recombinant plasmids will be a useful tool for further investigation aimed at improving ruminal fibre digestion.

Anaerobiosis↗
PubMed2001

Effect of the tropical forage calliandra on microbial protein synthesis and ecology in the rumen.

AIMS: To determine the effect of condensed tannins in Calliandra calothyrsus (calliandra) on rumen microbial function. METHODS AND RESULTS: Microbial populations, ruminal protein synthesis and fermentation end-products were measured in sheep fed roughage hay supplemented with calliandra (30%), with and without inclusions of polyethylene glycol (PEG) to counteract the effect of tannin. Molecular and conventional enumeration techniques were used to quantify rumen bacteria, fungi and protozoa, and protein synthesis was predicted from estimates of urinary purine excretion. The total number of cellulolytic bacteria, including populations of Fibrobacter succinogenes and Ruminococcus spp., was significantly lower in sheep supplemented with calliandra and these populations increased when animals were treated with PEG. By contrast, protozoa and fungi and the microbial group containing Bacteroides-Porphyromonas-Prevotella bacteria appeared to be less affected. The efficiency of microbial protein synthesis in the rumen was not altered significantly. CONCLUSION: Calliandra caused significant shifts in rumen microbial populations without changing the efficiency of protein synthesis. SIGNIFICANCE AND IMPACT OF THE STUDY: The effect of calliandra tannins on rumen digestion may result more from complexing with nutrients than direct inhibition of micro-organisms.

Ammonia↗
PubMed2001

Expression of a modified Neocallimastix patriciarum xylanase in Butyrivibrio fibrisolvens digests more fibre but cannot effectively compete with highly fibrolytic bacteria in the rumen.

AIMS: This study investigated the competitive abilities of two Neocallimastix patriciarum-derived xylanases constructs in Butyrivibrio fibrisolvens H17c (xynA and pUMSX) and their ability to compete in vivo. METHODS AND RESULTS: The digestibility of neutral detergent fibre (NDF) increased during co-culture of xynA or pUMSX and weakly cellulolytic, but not with highly cellulolytic, ruminococci. Competition studies among xynA, pUMSX and cellulolytic consortia demonstrated that xynA was the fittest. XynA did not persist at high levels in the rumen and was undetectable after 22 days. CONCLUSION: The construction of recombinant xylanolytic B. fibrisolvens does improve the digestibility of fibre above that of the native, but digestibility is still less than that of the most potent fibre digesters such as ruminococci. SIGNIFICANCE AND IMPACT OF THE STUDY: Fibre digestion may be improved by genetic manipulation of ruminal bacteria but ecological parameters, such as persistence in vivo and the niche of the organism, must be taken into account.

Animals↗
PubMed1999

Isolation and characterization of proteolytic ruminal bacteria from sheep and goats fed the tannin-containing shrub legume Calliandra calothyrsus.

Tannins in forages complex with protein and reduce the availability of nitrogen to ruminants. Ruminal bacteria that ferment protein or peptides in the presence of tannins may benefit digestion of these diets. Bacteria from the rumina of sheep and goats fed Calliandra calothyrsus (3.6% N and 6% condensed tannin) were isolated on proteinaceous agar medium overlaid with either condensed (calliandra tannin) or hydrolyzable (tannic acid) tannin. Fifteen genotypes were identified, based on 16S ribosomal DNA-restriction fragment length polymorphism analysis, and all were proteolytic and fermented peptides to ammonia. Ten of the isolates grew to high optical density (OD) on carbohydrates (glucose, cellobiose, xylose, xylan, starch, and maltose), while the other isolates did not utilize or had low growth on these substrates. In pure culture, representative isolates were unable to ferment protein that was present in calliandra or had been complexed with tannin. One isolate, Lp1284, had high protease activity (80 U), a high specific growth rate (0.28), and a high rate of ammonia production (734 nmol/min/ml/OD unit) on Casamino Acids and Trypticase Peptone. Phylogenetic analysis of the 16S ribosomal DNA sequence showed that Lp1284 was related (97. 6%) to Clostridium botulinum NCTC 7273. Purified plant protein and casein also supported growth of Lp1284 and were fermented to ammonia. This is the first report of a proteolytic, ammonia-hyperproducing bacterium from the rumen. In conclusion, a diverse group of proteolytic and peptidolytic bacteria were present in the rumen, but the isolates could not digest protein that was complexed with condensed tannin.

Animal Feed↗
PubMed1997

Ribotyping of adherent Lactobacillus from weaning pigs: a basis for probiotic selection based on diet and gut compartment.

Dietary inoculates for weaned pigs often include lacobacilli, but the effects of age and diet on the ecology of adherent lactobacilli are not well known. Four experimental treatments included 16 newborn piglets: a pre-weaning treatment (PW) included four pigs that were sacrificed at 28 days of age; a sow treatment (Sow) had four pigs that remained with the sow (Sow) from 28 to 38 days of age and were sacrificed at 38 days of age; and two treatments in which four pigs each, were placed on a corn-soy diet with (CSL), or without (CS) 40% lactose. Adherent lactobacilli were isolated from the pars esophagus, ileum, and cecum, and characterised phenotypically. A 23S rDNA probe hydrized toEcoRI orPstI digested DNA, and a 74.8% cut-off individualize isolates into 36 clusters. The most predominant strains found in the Sow, CSL, and CS treatments were the same, but different strains predominated in the PW animals. The most predominant strains found in the pars esophagus and ileum were the same, but different strains predominated in the cecum.

Journal Article↗
PubMed1997

Molecular beacons: trial of a fluorescence-based solution hybridization technique for ecological studies with ruminal bacteria.

Molecular beacons are fluorescent probes developed for solution rather than membrane hybridization. We have investigated the utility of these probes to study rumen microbial ecology. Two cellulolytic species, Ruminococcus albus and Fibrobacter succinogenes, were tested. Membrane and solution hybridizations gave similar results in competition experiments with cocultures of R. albus 8 and F. succinogenes S85.

Animals↗
PubMed1996

An rRNA approach for assessing the role of obligate amino acid-fermenting bacteria in ruminal amino acid deamination.

Ruminal amino acid degradation is a nutritionally wasteful process that produces excess ruminal ammonia. Monensin inhibited the growth of monensin-sensitive, obligate amino acid-fermenting bacteria and decreased the ruminal ammonia concentrations of cattle. 16S rRNA probes indicated that monensin inhibited the growth of Peptostreptococcus anaerobius and Clostridium sticklandii in the rumen. Clostridium aminophilum was monensin sensitive in vitro, but C. aminophilum persisted in the rumen after monensin was added to the diet. An in vitro culture system was developed to assess the competition of C. aminophilum, P. anaerobius, and C. sticklandii with predominant ruminal bacteria (PRB). PRB were isolated from a 10(8) dilution of ruminal fluid and maintained as a mixed population with a mixture of carbohydrates. PRB did not hybridize with the probes to C. aminophilum, P. anaerobius, or C. sticklandii. PRB deaminated Trypticase in continuous culture, but the addition of C. aminophilum, P. anaerobius, and C. sticklandii caused a more-than-twofold increase in the steady-state concentration of ammonia. C. aminophilum, P. anaerobius, and C. sticklandii accounted for less than 5% of the total 16S rRNA and microbial protein. Monensin eliminated P. anaerobius and C. sticklandii from continuous cultures, but it could not inhibit C. aminophilum. The monensin resistance of C. aminophilum was a growth rate-dependent, inoculum size-independent phenomenon that could not be maintained in batch culture. On the basis of these results, we concluded that the feed additive monensin cannot entirely counteract the wasteful amino acid deamination of obligate amino acid-fermenting ruminal bacteria.

Amino Acids↗
PubMed1996

How many ruminal bacteria are there?

With the development of strictly anaerobic techniques and habitat-simulating media, a variety of bacteria were isolated from the rumen in the 1940s and 1950s. Based on standard morphological and physiological characteristics, the microbial ecosystem of the rumen contains a very complex population of bacteria. In recent years, ruminal bacteria have been re-evaluated with newer, more objective, and genetically valid methods of classification. Ribosomes are complicated structures, and their DNA-encoding sequences are relatively free from selective pressure. Because ribosomes have evolved slowly, they provide a long-term natural history of evolution. The invariable and hypervariable regions of rRNA genes can be used to group bacteria into kingdoms, genera, and species. The 16S rRNA sequences have provided a basis for renaming some ruminal species (Bacteroides amylophilus is now Ruminobacter amylophilus and Bacteroides succinogenes is now Fibrobacter succinogenes) and for classifying at least one recently isolated ruminal bacterium (e.g., Clostridium aminophilum). The DNA:DNA hybridization is a more sensitive method of assessing bacterial relatedness than is 16S rRNA. Bacterial strains within a species should have a high degree of DNA:DNA homology, but some species of ruminal bacteria (e.g., Prevotella ruminicola and Butyrivibrio fibrisolvens) had highly unrelated strains. Studies of 16S rRNA and DNA:DNA hybridization indicate that the diversity of ruminal bacteria has been greatly underestimated. Traditional studies of phylogeny of ruminal bacteria were stymied by the fastidious growth requirements of many ruminal bacteria, and enumeration was tedious and inaccurate. Modern methods of bacterial classification do not require in vitro culture and have the potential of detecting even a single cell.

Animal Nutritional Physiological Phenomena↗
PubMed1995

Effect of weaning diet on the ecology of adherent lactobacilli in the gastrointestinal tract of the pig.

Sixteen pigs were included in an investigation of the effects of weaning and weaning diet on the ecology of adherent Lactobacillus species in the gastrointestinal tract. At 28 d of age four pigs were killed and were designated as the preweaning control (PW). Four pigs remained on the sow (Sow), four pigs were fed a corn-soy-lactose (CSL) diet, and the remaining four pigs were fed a corn-soy (CS) diet. Pigs from the latter three treatments were killed at 38 d of age. Tissue samples were taken from the pars esophagus, ileum, and cecum and the adherent lactobacilli were enumerated using Rogosa SL agar. Bacterial colonies were randomly selected from Rogosa SL agar plates and speciated using cell type, morphology, and substrate fermentation tests. The species data were used to calculate the Shannon, Simpson, and evenness diversity indices. Shannon and Simpson diversity index values when averaged across tissues were lower (P < .05) for PW than for postweaning treatments (Sow, CSL, and CS) and lower (P < .05) when pigs receiving sow's milk (PW and Sow) were compared with pigs receiving the dry diets (CSL and CS). The diversity of adherent Lactobacillus is altered by the form of the diet fed to weanling pigs, and statistical ecological methods provide a powerful way of analyzing the ecology of the gastrointestinal tract.

Animals↗
PubMed1994

Characterization of the nutritional interactions between organic acids and inorganic bases in the pig and chick.

Four experiments were conducted to characterize the interactions between fumaric (FA), malic (MA), or citric acid (CA) and NaHCO3. In two experiments, seven diets were formulated containing 2.5% FA, MA, and CA, with or without 2.3, 1.9, or 1.4% NaHCO3, respectively, as well as a control diet (no addition of organic acids or NaHCO3) for 28-d-old pigs (Exp. 1, corn-soy protein concentrate-based diet) and 1-wk-old chicks (Exp. 4, corn-soy-based diet). In Exp. 1, at 2 and 4 wk, the FA+NaHCO3 treatment resulted in greater average daily gain (ADG) and feed intake (ADFI) compared with the control (P < .05). In Exp. 2, 28-d-old pigs were fed corn-soy diets with .9, 1.6, and 2.3% NaHCO3 in addition to 2.5% FA. After wk 2, there was a quadratic response in ADG (P < .08) and ADFI (P < .05) when increasing levels of NaHCO3 were added to the diet. This was true at wk 4 for both ADG and ADFI (P < .05). In Exp. 3, finishing pigs were fed corn-soy diets containing 2.5% FA or 2.5% FA + 2.3% NaHCO3 added to a control diet. No effect (P < .05) of FA or NaHCO3 was observed. In Exp. 4, the combination of CA+NaHCO3 or MA+NaHCO3 was superior to FA+NaHCO3 for ADG (P < .08) and ADFI (P < .05) when fed to young chicks.

Animal Feed↗