B. Dehority - Academia.edu (original) (raw)

Papers by B. Dehority

Journal of Dairy Science, 1985

... Fermentation studies on inoculated herbages. J. Sci. Food Agric. 15:429. 9 Moon, NJ, LO Ely, ... more ... Fermentation studies on inoculated herbages. J. Sci. Food Agric. 15:429. 9 Moon, NJ, LO Ely, and EM Sudweeks. 1981. ... J. Sei. Food Agric. 17:264, 11 Shockey, WL, BA Dehority, and HR Conrad. 1985. Performance of lactating cows fed alfalfa ensiled with grain. J, Dairy Sci. ...

Journal of Dairy Science, 1967

The ability of nine pure strains of ru- men bacteria to digest the eelhflose and hemieellulose po... more The ability of nine pure strains of ru- men bacteria to digest the eelhflose and hemieellulose portions of an intact forage was investigated. Using a limiting' level of substrate, the extent of digestion of these components was measured in va13-ing maturity stages of both grasses and al- falfa. Bacteroides s~ccb~oge,~es strains were able to digest significantly greater amounts of cellulose from forages than were the other species. Two of the four strains of I¢~tmiuocoec~s fl~'e/'c~ci~,~ had a markedly reduced ability to digest eel- lulose from alfalfa. Of the seven eellulo- lytic strains, only three were able to di- gest forage hemicelluloses. These three strains, all rmninocoeci, digested consider- able amounts of hemicellulose from ))rome- grass, but had a very limited ability to digest alfalfa hemicellulose. Opposite re- suits were obtained with B(wtero,:des r~- mi~deola. B~tyrivibrio fibri~olve~s di- gested appreciable amounts of hemicellulose from both types of forage. Aeros~ all organisms and forages, the extent of both cellulose and hemieellulose digestion de- creased with forage maturity. Studies on the possible synergistic effect of com- bining two cultures in a single fermentation were conducted with four cellulolytic strains and one noneellulolytic strain. All possible combinations of two were used, and a significant increase in the extent of cellulose digestion was consistently observed when the noncellulolytic orgaldsm, B. r~- minicola, was combined with any of the four eellulolytic strains. Using a crude forage fractionation system, based on the solubility of forage dry matter in benzene-aleohol, hot water, 2% H~S0,, and 70% H..SO~, Htmgate (12) demonstrated the ability of several strains of ruminococci to digest both

Journal of Dairy Science, 1968

Per cent cellulose digestion values for twelve different forages~ under limiting substrafe condit... more Per cent cellulose digestion values for twelve different forages~ under limiting substrafe conditions, were obtained with seven strains of cellulolytic rlnnen bacteria and correlated with various in vivo parameters of forage digestibility. When the forages were considered by type (eight samples of grasses and four samples of alfalfa)~ correlations with all seven strains were very high. On the other hand, when all twelve forages were combined, cellulose digestion by four of the seven strains was highly correlated with in vivo dry matter digestibility (D~.ID) and cellulose digestibility (CD), and quite low correlation coefficients were obtained with the criteria of relative intake (RI) and nutritive value index (NVI). Considerably better correlation coefficients with NVI and RI were obtained with eellulose digestibility data from the three remaining strains. Combining the cellulose digestibility data with the chemical measurement of dry matter solubility (DMS) markedly improved the correlations with both NVI and RI. On the basis of these results, one organlsm from each of the two groups was selected, and cellulose digestion was measured on a seNes of 64 forages. Correlation eoefficients were calculated for the different types of forages (22 grasses~ 17 alfalfa and 25 mixed forages) and all forages combined. In addition, DMS values were combined with the di~'estibility data and similar correlations determined. For all 64 forages combined, the best correlation coefficients obtained were: RI, 0.76; NVI, 0.88; DMD, 0.89; CD, 0.90~ energy digestion (ED), 0.90. These correlations are similar to or somewhat higher than those obtained on this series of forages by ehemieaI and in vitro mixed culture fermen-

Journal of Dairy Science, 1959

... FROM ALFALFA TO VITAMIN A BY GUERNSEY AND }{OLSTEIN CALVES 1 HD EATON, GS MYERS, JR., -~ MART... more ... FROM ALFALFA TO VITAMIN A BY GUERNSEY AND }{OLSTEIN CALVES 1 HD EATON, GS MYERS, JR., -~ MARTHA W. DICKS, BA DEHORITY, AP GRIFO, JR., _~xl) R. TEICHMAN 3 Animal ... (6) DOLOE, KL, EATON, HD, AVA.~IPATO, JE, ~IOCHRIE, RD, ELLIOTT, FI, AND ...

Journal of animal science, 1970

Applied and environmental microbiology, 1991

Total and cellulolytic bacterial and fungal numbers were determined in ruminal and cecal contents... more Total and cellulolytic bacterial and fungal numbers were determined in ruminal and cecal contents of 20 blue duikers (Cephalophus monticola). The animals were equally divided by sex and fed two diets, either high roughage or high concentrate. The mean concentration for total bacterial numbers in the rumen was 26.0 x 10/g of contents, with values ranging from 2 x 10/g to 93 x 10/g. Cellulolytic numbers averaged 6.0 x 10/g with a range of 1.5 x 10/g to 24.0 x 10/g. No differences related to sex or diet were found. In contrast, total bacterial numbers in the cecum differed between diets (P < 0.02), i.e., 1,046 x 10 bacteria per g for animals fed the high-forage diet compared with 166 x 10/g for those fed the high-concentrate diet. Cellulolytic bacterial counts in the cecal contents averaged 3.1 and 7.0% of the total counts for the high-forage and high-concentrate diets, respectively. Low concentrations of fungi were found in both ruminal and cecal contents of some, but not all, anim...

The Journal of nutrition, 1962

1959 Biochemical and physiological changes in bovine hypovitaminosis A. Federation Proc., 18: 522... more 1959 Biochemical and physiological changes in bovine hypovitaminosis A. Federation Proc., 18: 522 (abstract). s See footnote 4.

American journal of veterinary research, 1964

The Journal of nutrition, 1964

Thirty-six pigs, weaned at 3 weeks of age, were depleted until their blood plasma vitamin A conce... more Thirty-six pigs, weaned at 3 weeks of age, were depleted until their blood plasma vitamin A concentrations had decreased to less than 12%g/100 ml Â£tly^f%the,n suPP^mented fÂ°r75 Â±1 days with vitamin A or vitamin A add or both. Blood plasma vitamin A increased with vitamin A intake but decreased and was unrelated to any level of vitamin A acid fed. Liver vitamin A increased wÃ¼h vitamin A and vitamin A acid intake although values for the pigs fed vUarÃ•Ã•n A le d were low In addition, those pigs fed a combination of vitamin A and v aS n A ac d had considerably higher liver vitamin A concentrations than those pigs fed viÃ¯amrnA alone, indicating that vitamin A acid had a sparing effect on liver vitamin A i^t>T Pig. No vitamin A acid could be detected in the plasma or Sver A sirSTr Decrease in cerebrospinal fluid pressure occurred with an increase in vitamin A or acid intake, suggesting that vitamin A acid was effective in meeting this requirement Cerebrospinal fluid pressure proved to be an adequate cri e uring the vitamin A status of the pig when fed either vitamin A or vitam"n

Journal of animal science, 2003

A protozoa-specific primer (P-SSU-342f) was designed and paired with a eukarya-specific primer to... more A protozoa-specific primer (P-SSU-342f) was designed and paired with a eukarya-specific primer to amplify a 1,360-bp fragment of DNA encoding protozoal small subunit (SSU) ribosomal RNA from ruminal fluid of cows fed a mixed forage:grain diet or alfalfa hay. Sequencing of clones showed that P-SSU-342f is specific to ruminal protozoa and, with slight modifications, the primer will be useful for ecological studies of ruminal protozoa.

Journal of animal science, 2001

In a preliminary study, the addition of antibiotics was shown to reduce bacterial concentrations ... more In a preliminary study, the addition of antibiotics was shown to reduce bacterial concentrations in Entodinium exiguum cultures by more than 99% in 4 h, whereas the protozoal population was apparently unaffected. Using this procedure, the growth and amylolytic capability of Entodinium exiguum, in the presence or absence of live bacteria, was studied in vitro. Treatments for Trial 1 were protozoa plus antibiotics (PA), PA plus autoclaved bacteria (PAB), protozoa plus living bacteria (PLB), and only bacteria (BAC). Autoclaved or non-autoclaved cornstarch was used as an energy source. Treatment main effects were as follows: higher concentration of E. exiguum in PLB than in PA or PAB at 24 and 48 h (P < 0.01); PA and PAB were not different (P > 0.05); concentrations of E. exiguum higher in autoclaved cornstarch at 12 h (P < 0.05) but lower than in non-autoclaved cornstarch at 24 and 48 h (P < 0.01); and starch digestion in PLB was higher than in PA and PAB at all time period...

Reproduction, nutrition, development

Whether live bacteria are required to culture the rumen protozoa Entodinium exiguum and E. caudat... more Whether live bacteria are required to culture the rumen protozoa Entodinium exiguum and E. caudatum in vitro was studied. Treatments were protozoa plus antibiotics (PA), PA plus autoclaved bacteria (PAB) or protozoa plus live bacteria (PLB). Generation times at 24 h were 22.8 and 31.0 h for E. exiguum and E. caudatum. Protozoal concentrations were unaffected by the absence of bacteria up to 48 h. After 72 h, E. exiguum, concentrations were higher in PLB than PA or PAB. With E. caudatum differences between PLB and PA were only observed at 96 h. Thus, a requirement for live bacteria appears to be manifested in culture periods longer than 48 (E. exiguum) and 72 (E. caudatum) h. Although differences between PLB and PAB indicate a metabolic dependence for bacteria or a long-term antibiotic effect, non-significant differences between PAB and PA suggest that the effect is also related to a nutritive bacterial contribution.

Journal of animal science, 1996

The synergistic and inhibitory interactions observed between Fibrobacter succinogenes A3c, Prevot... more The synergistic and inhibitory interactions observed between Fibrobacter succinogenes A3c, Prevotella ruminicola H2b, and Ruminococcus flavefaciens B34b in the digestion of forage cellulose were studied in detail. Orchardgrass and alfalfa hays, both at two maturity stages, were used as substrates. Sequential inoculation procedures were developed whereby a second inoculation was made after the initial fermentation was killed. Total cellulose digestion from sequential addition of the organisms was then compared to values obtained in simultaneous co-culture. When the noncellulolytic P. ruminicola was co-cultured with either of the two cellulolytic species (F. succinogenes or R. flavefaciens) forage cellulose digestion numerically increased over that of the cellulolytic species alone. In contrast, decreases from co-culture values were noted with sequential addition of the organisms. When F. succinogenes and R. flavefaciens were co-cultured, cellulose digestion was reduced compared to F....

The Journal of applied bacteriology, 1994

Procedures for sequential addition experiments were developed to study the mechanisms involved in... more Procedures for sequential addition experiments were developed to study the mechanisms involved in the synergistic and inhibitory interactions observed in forage hemicellulose digestion by rumen bacterial cocultures. One organism was allowed to ferment a forage substrate, the culture tube was sterilized and then inoculated with a second organism. No differences were found in the extent of degradation or utilization between fermentations sterilized by oxidation or heat, and based on ease of handling, heat was used in all subsequent experiments. Studies were conducted with Fibrobacter succinogenes A3c, Ruminococcus flavefaciens B34b and Prevotella ruminicola H2b, singly and in all possible combinations. Results from the sequential addition studies substantiated earlier suggestions that the increase observed in hemicellulose utilization results from initial solubilization of the hemicellulose from the forage by the non-utilizer and subsequent utilization of subsequent utilization of thi...

Journal of Dairy Science, 1961

... d Animal Husbandry Research Division, USDA, Beltsville, Md. ... Heart and skeletal muscles we... more ... d Animal Husbandry Research Division, USDA, Beltsville, Md. ... Heart and skeletal muscles were homogenized in an Omni-Mixer and the liver ground in a Hobart food chopper, sampled, and the samples held at --18 C. for subsequent mineral, creatine, cholesterol (liver), nitrogen ...

Journal of General Microbiology, 1990

A container with nylon and stainless steel mesh screens (10 pm and 20 pm pores, respectively), wh... more A container with nylon and stainless steel mesh screens (10 pm and 20 pm pores, respectively), which allowed the passage of bacteria and soluble substrate but restricted the passage of protozoa, was used to investigate the phenomena of sequestration, migration and lysis of protozoa in the rumen of steers. After feeding, the concentration of Isotrichidae in the rumen increased 8-7-fold within 40 min and then decreased 88% by 4 h; however, the concentration of Isotrichidae inside the containers remained almost constant. Fluctuations in concentrations of Isotrichidae were shown to be due to migration and sequestration within the rumen. Ophryoscolecidae did not exhibit the phenomena of sequestration and migration. When steers were fed once a day, about 50% of the decrease in the concentration of Ophryoscolecidae immediately after feeding could be attributed to the dilution effects of feed and water and/or passage out of the rumen. The remaining 50% of the decrease appeared to be from cell lysis, resulting in a wasteful recycling of protozoal protein.

Journal of Dairy Science - J DAIRY SCI, 1961

ABSTRACT

The Journal of Eukaryotic Microbiology, 1997

Three complete 18s ribosomal RNA gene sequences from the rumen ciliates, Entodinium caudatum (1,6... more Three complete 18s ribosomal RNA gene sequences from the rumen ciliates, Entodinium caudatum (1,639 bp), Epidinium caudatum (1,638 bp), and Polyplastron multivesiculatum (1,640 bp) were determined and confirmed in the opposite direction. Trees produced using maximum parsimony and distance-matrix methods (least squares and neighbour-joining), with strong bootstrap support, depict the rumen ciliates as a monophyletic group. Entodinium caudatum is the earliest branching rumen ciliate. However, Entodiniuin simplex does not pair with En. caudatum, but rather with Polyplastron multivesiculatum. Signature sequences for these rumen ciliates reveal that the published SSrRNA gene sequence from En. simplex is in fact a Polyplastron species. The free-living haptorian ciliates, Loxophyllum, Homalozoon and Spathidium (Subclass Haptoria), are monophyletic and are the sister group to the rumen ciliates. The litostomes (Class Litostomatea), consisting of the haptorians and the rumen ciliates, are also a monophyletic group.