Biomedical subjects

F L Fluharty

Publications and source records attributed to F L Fluharty.

27 records · Page 2Linked to original sources

PubMed1996

Effects of feed and water deprivation on ruminal characteristics and microbial population of newly weaned and feedlot-adapted calves.

Two experiments were conducted to determine the effects of length of feed and water deprivation on ruminal microbes and ruminal characteristics. In Exp. 1, treatments were as follows: 1) weaned, but not trucked (0 h), 2) weaned, trucked, and fasted for 48 h (48 h), and 3) weaned, trucked, and fasted for 72 h (72 h). On d 0 (arrival back at the feedlot after treatment), DMI, ruminal contents (P < .05) decreased as length of feed and water deprivation increased. However, on d 4, there were no longer any differences (P > .10) in DMI or weight of ruminal contents. On d 0, percentage of ruminal DM in the 48- and 72-h treatment groups was lower (P < .01) than in the 0-h treatment group, but there were no differences (P > .10) by d 4. After the steers used in Exp. 1 had been in the feedlot for 28 h, they were reallotted, and the three treatments (except for weaning) were repeated; the 0-h group remained at the feedlot. On d 0, DMI of the 48-h group was lower (P < .05) than that of the 0-h group; DMI of the 72-h group was intermediate. On d 0, the 0-h treatment group had a greater ruminal DM percentage than the 48- and 72-h treatment groups (P < .05); however, due to large within-treatment variation the total weight of ruminal contents did not differ (P > .10) among treatments. There were no decreases (P > .10) in cellulolytic or total bacterial concentration or in the ruminal numbers of cellulolytic or total bacteria due to length of feed and water deprivation on d 0 in either Exp. 1 or 2. In both trials, 48 and 72 h of feed and water deprivation decreased (P < .05) protozoal numbers on d 0 and 4 compared with the 0-h treatment group.

Aging↗

PubMed1996

Effects of dietary energy source and level on performance of newly arrived feedlot calves.

Three experiments were conducted with Simmental x Angus crossbred steers to determine the effects of energy source and level on performance of newly arrived feedlot calves. In trial 1, 68 steers (initial BW 215 +/- 9.4 kg) were used in a 2 x 3 factorial experiment to determine the effects of receiving diet and previous creep feed on performance. Diets were composed primarily of either corn silage, corn silage + alfalfa pellets + dry corn, or dry corn + alfalfa pellets. For the 41-d trial, calves fed the corn silage-based diet had greater (P < .05) ADG and feed efficiencies than calves fed the other two diets. In Trial 2, 60 steers (initial BW 212 +/- 4.6 kg) were used in a 28-d completely randomized design experiment to determine the effects of 16% CP receiving diets containing 70, 75, 80 or 85% concentrate on performance. There were no differences (P > .10) in ADG or feed efficiency due to dietary concentrate level. In Trial 3, 77 steers (initial BW 226.3 +/- 3.0 kg) were used in a 2 x 3 factorial experiment to determine the effects of dietary concentrate and protein levels on performance during a 28-d receiving period. The factors were concentrate level (70 vs 85% concentrate) and protein level (12.5%, 16%, or phase-fed at 23%, 17%, 14%, and 12.5% during wk 1, 2, 3, and 4, respectively). During wk 1, calves fed the 85% concentrate diet had greater (P < .01) DMI, ADG, and feed efficiency compared with 70% concentrate. Calves fed the 16% CP and phase-fed protein diets had greater (P < .01) DMI, ADG, and greater (P < .02) feed efficiency than calves fed the 12.5% CP diets. Receiving diets containing at least 16% CP and > 70% concentrates are beneficial to calves during the first week after feedlot arrival.

Aging↗

PubMed1995

Effects of protein concentration and protein source on performance of newly arrived feedlot steers.

In Trial 1, 240 crossbred steers (initial BW 243 +/- 8 kg) were used in a 2 x 4 factorial experiment to determine the effects of receiving diet CP concentration (12, 14, 16, or 18%) and source (spray-dried blood meal [SDBM] vs soybean meal [SBM]) on steer performance. There were linear (P < .01) increases in ADG and feed efficiency during wk 1. For the entire trial, there was an increase (P < .01) in feed efficiency with increasing CP concentration and diets containing SDBM compared with those containing SBM. In Trial 2, 240 crossbred steers (initial BW 246 +/- 14 kg) were used in a completely randomized design experiment to determine the effects of receiving diet CP concentration (11, 14, 17, 20, 23, or 26%) on steer performance. Average daily gain and feed efficiency increased (P < .01) with increasing CP concentration during wk 1. There were quadratic (P < .01) responses to CP concentration for final weight, ADG, and feed efficiency. In Trial 3, 216 steers (initial BW 238 +/- 1 kg) were used to determine the effects of receiving diet protein sources on steer performance. The control diet used SBM as the supplemental CP source and was formulated to contain 12.5% CP. The other five protein sources were corn gluten meal (CGM), ring-dried blood meal (RDBM), SDBM, fish meal (FM), and SBM. For these five CP sources, diets were formulated to contain 23% CP during wk 1, 17% CP during wk 2, and 12.5% CP during wk 3 and wk 4. During wk 1, control steers had the lowest ADG (P < .07) and feed efficiency (P < .01) whereas steers fed RDBM and SDBM had the highest (P < .01) feed efficiency. Increased CP concentrations are needed early in the receiving period, when DMI is low.

Animals↗

PubMed1994

Ruminal characteristics, microbial populations, and digestive capabilities of newly weaned, stressed calves.

Eight ruminally fistulated steers, 7 to 8 mo old, were used in a completely randomized, 2 x 2 factorial experiment to determine the effects of energy density and protein source in receiving diets on in situ DM, NDF, and N disappearance, concentrations of ruminal bacteria, protozoa, ammonia, and pH. Two energy densities (1.80 and 1.48 Mcal/kg of NEm) and two protein sources (spray-dried blood meal [SDBM] and soybean meal [SBM]) were compared. Fistulated steers were weaned, transported by truck, and held in a sale barn before their arrival at the feedlot. On d 0 (day of arrival at the feedlot), DMI was 62% of DMI on d 7 after arrival. Overall, feeding a high-energy diet resulted in lower (P < .01) in situ DM disappearance (DMD) of orchardgrass than feeding a low-energy diet at both 24 and 48 h. In situ 24-h DMD averaged 46.6% on d-3 and 41.6% on d 0, whereas 48-h in situ DMD on d -3 and 0 averaged 58.2 and 58.6%, respectively, indicating the ruminal microbial population was not inhibited in its ability to digest available substrate. Additionally, there were no differences (P > .10) in 48-h in situ NDF disappearance between d -3 and 0 (58.8 vs 57.8%), respectively. No differences (P > .10) occurred in the concentration of total bacteria, or cellulolytic bacteria, due to feed and water deprivation. Concentration of total protozoa was lower (P < .05) on d 0 than at any other time. Entodinium averaged 72.5% of genera before weaning, and more than 90% of genera found on all treatments by d 21. Diplodinium and Epidinium percentages tended to decline after weaning. Isotricha concentrations were low and Dasytricha were eliminated after d 7. In conclusion, the concentration of ruminal bacteria and the ability to digest available substrate were not decreased immediately after weaning, trucking, and 24 h of feed and water deprivation.

Ammonia↗

PubMed1994

The influence of intake level and corn processing on digestibility and ruminal metabolism in steers fed all-concentrate diets.

The effects of intake (ad libitum and 70% of ad libitum) and corn processing (whole or rolled) on digestion, ruminal metabolism, and blood metabolites were determined in a 2 x 2 factorial experiment using eight ruminally fistulated steers. All-concentrate diets were fed with adjustments to dietary concentrations of N, vitamins, and minerals to ensure equal daily intake of these nutrients. Digestion of DM, OM, and starch were affected by an intake x processing interaction (P < .03). Starch digestion for the low-intake, whole-corn diet was much lower than that for the other three diets. This decrease in starch digestion was the major reason for the interaction. Nitrogen digestion was improved (P < .03) with limited intake but was not affected by processing. Ruminal volume and ruminal turnover (percentage/hour) were both reduced (P < .03) on the low-intake diet. Molar proportion of acetate was reduced and propionate was increased (P < .01) for steers receiving high intake of rolled corn compared with the other three diets. Butyrate concentrations were increased (P < .01) when corn was rolled before feeding. Ruminal pH was higher immediately before feeding for steers receiving whole corn than for those receiving rolled corn. Decreases in pH were observed for rolled corn 2 to 9 h after feeding, suggesting a faster rate of fermentation of rolled corn than of whole corn. Concentrations of blood glucose and insulin were not affected by intake or processing. It was concluded that processing corn can improve DM and OM digestibility if intake is restricted and that N digestion is improved with restricted feeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Ammonia↗

PubMed1994

Effects of energy density and protein source on diet digestibility and performance of calves after arrival at the feedlot.

Sixty Angus crossbred steers (initial BW, 237 kg) were used in a 2 x 2 factorial experiment to determine the effects of energy density and protein source in receiving diets on steers performance and total tract nutrient digestion. The factors compared were energy density (1.80 vs 1.48 Mcal/kg of NEm, referred to as high-energy and low-energy, respectively) and protein source (ring-dried blood meal [BM] vs soybean meal [SBM]). Diets containing BM resulted in a 10.6% greater (P < .09) ADG and a 7.6% improvement (P < .05) in efficiency of feed utilization compared with those containing SBM. High-energy diets resulted in an 8.7% improvement (P < .05) in feed efficiency vs low-energy diets. Dry matter digestibility (DMD), NDF digestibility (NDFD), and CP digestibility (CPD) were exceptionally high during wk 1, when DMI was approximately 1.5 kg/d. Nutrient digestibility declined during wk 2 and 3, as intake increased, before stabilizing between wk 4 and 6. Additionally, NDFD was not consistently lower (P > .10) during this study for high-energy diets than for low-energy diets. The results of the overall performance data indicate that, compared to SBM, feeding BM may improve ADG and feed efficiency during the receiving period when dietary CP is approximately 13%. Additionally, DMD, NDFD, and CPD were higher on d 7 than at any other time, indicating that by d 7 ruminal function was not adversely affected. Therefore, it seems that the reduced feed intake and growth rate normally seen during the first 2 wk in the feedlot is not caused by a reduction in diet digestibility.

Animal Feed↗

PubMed1992

Effects of supplemental protein source and alkaline hydrogen peroxide treatment of wheat straw on site of nutrient digestion and flow of nitrogenous compounds to the duodenum of steers.

The objective of this study was to determine the effects of soybean meal (SBM) or spray-dried blood meal (BM) supplementation of diets based on untreated (UNT-WS) or alkaline hydrogen peroxide-treated wheat straw (AHP-WS). A 4 x 4 Latin square design with a 2 x 2 factorial arrangement of treatments was used. Variables included nutrient digestion and flow to the duodenum. Four Simmental steers (average weight 477 kg) fitted with ruminal and duodenal cannulas were fed 65% UNT-WS or AHP-WS based diets in 12 equal portions daily. Diets were formulated to contain 10% CP. Chromic oxide was used as the digesta flow marker and purines were used as the microbial marker. There were no straw type x protein source interactions. Total tract and ruminal OM digestibility were approximately 25% greater (P < .04) when AHP-WS was fed than when UNT-WS was fed. Source of protein did not affect (P > .10) OM or fiber digestion in the rumen or total tract. Ruminal digestion of NDF and ADF was increased (P < .01) by 51 and 40%, respectively, when AHP-WS was fed than when UNT-WS was fed. Main effect means (P > .10) for N flow to the duodenum as a percentage of N intake were 128.2, 142.5, 133.4, and 137.6 for UNT-WS, AHP-WS, SBM, and BM treatments, respectively. Despite increased (P < .01) ruminal OM digestion for AHP-WS, microbial N flow to the duodenum was greater (P < .01) when UNT-WS was fed than when APH-WS was fed.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acids↗

PubMed1992

Relationship between rumen bacterial concentrations and total numbers.

Based on data from 33 sheep, bacterial concentrations per gram of rumen contents were correlated highly with total bacterial numbers (r = .99). Diets ranged from all forage to 90% concentrate. Similar data were obtained from cattle fed a corn silage diet (r = .95); however, the slope of the regression lines differed between species. Weight of rumen contents was correlated poorly with total bacterial numbers.

Animals↗

PubMed1990

Effects of calcium soaps of long-chain fatty acids on feedlot performance, carcass characteristics and ruminal metabolism of steers.

Two trials were conducted to determine the effects of calcium soaps of long-chain fatty acids (calcium soap) on feedlot performance, diet digestibility, carcass characteristics and ruminal metabolism of steers fed diets (85% concentrate:15% corn silage) containing 0, 2, 4 or 6% calcium soap. In Trial 1, increasing calcium soap decreased (P less than .05) DM, CP and gross energy intake but increased total fatty acid intake. Feed to gain ratio tended to improve with increased calcium soap; gross energy conversion was not affected (P greater than .05) by diet. Average daily gain and hot carcass weight decreased (P less than .05) with addition of calcium soap; other carcass characteristics were not affected (P greater than .05). Apparent digestibilities of DM, N, energy and ash were not affected (P greater than .05) by calcium soap. Neutral detergent fiber digestibility increased linearly (P less than .08) with increasing calcium soap, whereas digestibility of total fatty acids was affected quadratically (P less than .05); fatty acid digestibility was similar among 0, 2 and 4% calcium soap diets but decreased for the 6% calcium soap diet. In Trial 2, increased calcium soap did not affect (P greater than .05) ruminal VFA concentrations, pH or in sacco NDF disappearance of orchardgrass following 12, 24 and 48 h of incubation. Calcium soap increased (P less than .07) ruminal concentrations of calcium soap fatty acids at 1, 2, 4 and 8 h postfeeding. Calcium soap did not improve performance of feedlot cattle fed high-concentrate diets. Further, calcium soap did not affect ruminal fermentation and did not dissociate significantly even when ruminal pH was below 6 for extended periods of time.

Animal Feed↗