PubMed HealthSearch

Biomedical subjects

J T Huber

Publications and source records attributed to J T Huber.

At least 19 recordsLinked to original sources

Effects of supplemental fat and protein source on ruminal fermentation and nutrient flow to the duodenum in dairy cows.

Four lactating Holstein cows, fitted with ruminal and T-type duodenal cannulas, were used in a 4 x 4 Latin square design for four periods (14 d each). Treatments were 1) medium fat and low quality protein, 2) medium fat and high quality protein, 3) high fat and low quality protein, and 4) high fat and high quality protein. Fat was supplemented by addition of 2.5% prilled fatty acids to high fat diets. The low quality diets contained corn gluten meal and 0.47% Lys, and the high quality diets contained a mixture of fish, blood, and soybean meals and 0.77% Lys. The percentage of Met was similar for all diets (mean, 0.28%). Diets contained 35 to 38% steam-flaked sorghum and 32% chopped alfalfa hay. Dietary CP averaged 18%, and all diets were high in RUP (44% of CP). Yields of milk, milk protein, and SNF were increased by added fat and by high quality protein. Ruminal NH3 and butyrate were increased by supplemental fat. Cows fed high quality protein had increased ruminal VFA, propionate, butyrate, and valerate, but decreased ratios of acetate to propionate. Essential AA concentrations in coccygeal plasma and arteriovenous differences across the mammary gland were higher for Lys and lower for Leu in cows fed high quality protein than in those fed low quality protein.

Animal Feed

Integrating health sciences librarians into biomedicine.

Vanderbilt University Medical Center (VUMC) developed a model training program to prepare current and future health sciences librarians for roles that are integrated into the diverse fabric of the health care professions. As a complement to the traditional and theoretical aspects of a librarian's education, this mixture of supplemental coursework and intensive practical training emphasizes active management of information, problem-solving skills, learning in context, and direct participation in research, while providing the opportunity for advanced academic pursuits. The practical training will take place under the auspices of an established Integrated Advanced Information Management Systems (IAIMS) library that is fully integrated with the Health Center Information Management Unit and Academic Biomedical Informatics Unit. During the planning phase, investigators are analyzing the model's aims and requirements, concentrating on (a) refining the current understanding of the roles health sciences librarians occupy; (b) developing educational strategies that prepare librarians to fulfill expanded roles; and (c) planning for an evaluation process that will support iterative revision and refinement of the model.

Certification

Electronic information retrieval in nursing.

Electronic information networks are explored in terms of the political and economic impact of such concepts as the National Information Infrastructure. The relevancy of electronic information retrieval to nursing is discussed as it applies to current health-care information management. Electronic information sources applicable to nursing are described along with examples of how they may be utilized. Network functions, such as bulletin boards, Freenets and literature searches, are explained and the implications for evolution of health-care delivery are summarized.

Communication

Effect of substituting steam-flaked sorghum for concentrate on lactation and digestion in dairy cows.

Thirty-five lactating cows (110 DIM), allotted to five dietary treatments for 70 d, were fed 0, 15, 30, or 45% of dietary DM as steam-flaked sorghum grain (360 g/L) in place of equal amounts of a mixture (DM basis) of 40% steam-rolled corn, 13% rolled barley, 20% wheat mill run, and 27% ground beet pulp in four diets. Thinly flaked sorghum grain (283 g/L) was also fed at 15% of dietary DM. The DMI tended to increase as flaked sorghum increased. Yields of milk and milk protein and percentages of milk protein and SNF increased linearly as sorghum increased. Milk yield of cows fed 15% of DM as the thinly flaked sorghum was higher than for cows fed the 360 g/L flake at 15% and similar to that of cows fed the 360 g/L flake at 30 or 45%. Feed efficiencies and changes in BW and body condition score were unaffected by treatment. As steam-flaked sorghum increased, digestibilities of DM, OM, ADF, NDF, and CP tended to decrease, except for the thinly flaked sorghum fed at 15% of DM. Apparent starch digestibility in the total tract was unaltered by diet. The 30 to 45% of DM fed as steam-flaked sorghum grain (360 g/L) increased yields of milk and milk protein, and thinly flaked sorghum (283 g/L) fed at 15% of DM increased milk yields over that of the control diet or that with the 360 g/L flake at 15% of DM.

Animal Feed

Effect of sorghum grain processing on site and extent of digestion of starch in lactating dairy cows.

Four lactating Holstein cows, fitted with T-type cannulas in the proximal duodenum were used in a 4 x 4 Latin square design to study the effects of sorghum grain processing on site of digestion of nutrients. Diets were steam-rolled corn, dry-rolled sorghum, steam-flaked sorghum, and an equal mixture of steam-flaked and dry-rolled sorghum as 43% of DM in a TMR (35:65, ratio of forage to concentrate). Intake and duodenal starch for all diets averaged 6.8 and 2.1 kg/d. Apparent total tract and ruminal digestibilities of starch for the respective diets averaged 81, 60, 70, and 60 and 97, 85, 91, and 89%. Starch digestibilities in the intestine were higher for steam-flaked than for dry-rolled or mixed sorghum (83 vs. 63 and 61%). Consistent with less postruminal passage of starch, cows fed steam-flaked sorghum had higher fecal pH than did cows on other treatments. No effects of diet occurred on NDF or ADF digestibilities. Compared with dry rolling of sorghum, steam flaking increased the digestibility of starch in the rumen from 60 to 81% and in the small intestine from 63 to 83%, increasing digestible starch intake 9% (6.4 vs. 5.9 kg/d). Values for steam-rolled corn were intermediate. Microbial protein in the rumen was not significantly altered by diet.

Animal Feed

Influence of steam-flaked sorghum grain and supplemental fat on performance of dairy cows in early lactation.

Effects of sorghum grain processing and fat supplementation on milk yield and composition and nutrient digestibilities were studied. Thirty-six Holstein cows were assigned at 5 d of lactation for 91 d to treatment: 1) dry-rolled sorghum, no added fat; 2) dry-rolled sorghum plus Ca salts of long-chain fatty acids; 3) steam-flaked sorghum, no added fat; and 4) steam-flaked sorghum plus Ca salts of long-chain fatty acids. Fat increased ether extract in diets from 5.7 to 7.5% of DM. Milk yield was 4.0 kg/d (12%) higher for cows fed steam-flaked than dry-rolled sorghum. Fat tended to decrease milk yield because of lower DMI, and feed efficiencies increased 15%. Milk protein decreased .14% on dry-rolled sorghum with added fat, but only .01% on the steam-flaked diet. Milk protein yield was higher for cows fed flaked than rolled sorghum. Flaking decreased milk fat percentage, but not yield. Added fat decreased shorter chain fatty acids in milk (C4 to C14), but oleic acid increased. Flaking increased C10, C12, and C14, but decreased oleic acid. Digestibilities for DM, CP, starch, and ether extract were higher for flaked and fat-supplemented diets. Flanking of sorghum prevented the milk protein decrease reported for early lactation cows fed added fat.

Animal Feed

Effect of enzyme treatment or steam-flaking of sorghum grain on lactation and digestion in dairy cows.

Effects of addition of a fungal enzyme (reported to have amylolytic and proteolytic activities) to dry-rolled or steam-flaked sorghum grain (40% of dietary DM) were tested for 70 d with 36 lactating Holstein cows in a 2 x 2 factorial arrangement of treatments. Compared with dry-rolling, steam-flaking resulted in increased yield of milk, milk protein, and 3.5% FCM; percentage of milk protein; and efficiency of feed utilization (FCM/DMI). Milk casein (as a percentage of milk N) was not altered, but milk urea N was lower, for cows fed steam-flaked sorghum. With steam-flaking, milk fat percentage decreased, short-chain fatty acids (C8 to C14) increased, but long-chain fatty acids (C16 to C18) were not affected. No yield parameters were altered by enzyme addition, except that the percentage of lactose in milk increased (5.02 vs. 4.96%). Steam-flaking of sorghum grain increased digestibilities of DM, OM, and starch (63 vs. 57%; 66 vs. 59%; and 98 vs 83%, respectively) compared with dry rolling. Enzyme addition did not affect starch digestibility, but digestibilities of DM, OM, CP, and NDF were greater than flaked grain was treated with enzyme, resulting in significant interaction effects. This study demonstrated higher milk and milk protein yields for cows fed steam-flaked sorghum than for cows fed dry-rolled sorghum, but addition of a sorghum-specific enzyme had no significant effect.

Animal Feed

Cross-platform hypermedia examinations on the Web.

The authors developed a multiple-choice medical testing system delivered using the World Wide Web. It evolved from an older, single-platform, locally-developed computer-based examination. The old system offered a number of advantages over traditional paper-based examinations, such as digital graphics and quicker, easier scoring. The new system builds on these advantages with its true cross-platform design and the addition of hypertext learning responses. The benefits of this system will increase as more medical educational resources migrate to the Web. Faculty and student feedback has been positive. The authors encourage other institutions to experiment with Web-based teaching materials, including examinations.

Clinical Clerkship

Quality of published reports of the prognosis of community-acquired pneumonia.

OBJECTIVE: To systematically assess the quality of published reports of the prognosis of community-acquired pneumonia using a formal quality assessment instrument. DESIGN: Retrospective review of studies published during 1966-1991. ARTICLES: 108 articles related to the prognosis of community-acquired pneumonia retrieved by a computerized search. INTERVENTION: All articles, blinded to author(s), journal title, year of publication, and study institution(s), were independently reviewed by two investigators using a ten-item quality assessment instrument designed to evaluate: 1) identification of the inception cohort (4 items), 2) description of referral patterns (1 item), 3) subject follow-up (2 items), and 4) statistical methods (3 items). Adherence to each of the ten individual quality items and an overall quality score were calculated for all articles and across three time periods. MAIN RESULTS: Among all 108 articles that underwent quality assessment, 30 were published from 1966 to 1979, 61 from 1980 through 1989, and 17 from 1990 through 1991. The mean total quality score of all articles was 0.55 (range 0.22-0.90). There was a significant trend toward improvement in total quality scores over the three time periods (0.50 to 0.56 to 0.65; p < 0.001). However, several systematic errors in the study design or reporting of these studies were discovered throughout time: only 3.7% provided comparative information about nonenrolled patients, 28.7% determined whether the study institution was a referral center, 36.1% specified inclusion or exclusion criteria, and 45.5% used appropriate statistical analyses to adjust for more than one prognostic factor. CONCLUSIONS: Despite improvement in overall quality of published articles, systematic errors exist in the design and reporting of studies related to the prognosis of community-acquired pneumonia. The quality assessment tool employed in this study could be used to guide the development of high-quality outcomes research in the future.

Adult

Influence of yucca extract on ruminal metabolism in cows.

Two trials were conducted to determine the influence of yucca extract on ruminal digestion, fermentation, and ammonia patterns using ruminally and duodenally cannulated dairy cows. In Trial 1, urea at 0 or 1% of the diet and yucca extract at 0 or 4 g/d formed four dietary treatments in a 2 x 2 factorial arrangement. The experimental design was a 4 x 4 Latin square with 15-d periods. Duodenal digesta were sampled every 6 h during the last 4 d of each period to determine OM and ADF digestibilities and bacterial protein synthesis in the rumen using Cr2O3 and 15N markers. Ruminal digestibilities were (percentage): OM 46.3 vs 43.0%, and ADF 35.9 vs 41.4%, with or without Deodorase. Microbial protein entering the duodenum averaged 2.7 vs 3.1 kg/d for the respective treatments. Ruminal measurements were not affected by treatment (P > .10). In Trial 2, five cows were used in a 5 x 5 Latin square with 7-d periods. Treatments were 0, 2, 4, 6, and 8 g/d of yucca extract administered via ruminal cannulas. Ruminal fluid was sampled 0, 1, 2, 4, 7, 11, 16, and 22 h after feeding during the last 2 d of each period. Average ruminal NH3 N ranged from 31.4 to 35.4 mg/dL, pH 5.99 to 6.18, and total VFA from 120 to 129 mM, and all did not differ among treatments (P > .10). Yucca extract administered at 4 g/d did not significantly affect ruminal digestibilities of OM and ADF, and up to 8 g/d did not affect ruminal NH3, pH, or VFA.

Ammonia

Effect of steam flaking of corn and sorghum grains on performance of lactating cows.

The objective of this study was to compare the relative feeding value of sorghum versus corn grain in rolled or steam-flaked forms in diets for lactating dairy cows. Twenty-four Holstein cows (averaging 110 DIM) were divided into four groups and fed diets of 40% grain as dry-rolled sorghum, steam-rolled corn, steam-flaked sorghum, or steam-flaked corn for 70 d. Compared with rolling, flaking of both grains increased yields of milk, milk protein and fat, and protein percentage of milk, but differences tended to be greater for sorghum than for corn. Efficiency of feed utilization was higher for steam-flaked than for dry-rolled sorghum but was unaffected by corn processing. Flaking of both grains increased total tract digestibilities of DM, OM, CP, starch, ADF, and NDF. Estimates for NEL were 21% higher for flaked than for rolled sorghum and 6% higher for flaked than for rolled corn. No differences in performance of cows existed between corn and sorghum grains. Cows fed 40% of their diet as steam-flaked sorghum or corn yielded more milk and milk protein than those fed the rolled form of the grains, and no differences existed between types of grain fed.

Animal Feed

Effect of isocaloric infusion of glucose in the rumen or propionate in the duodenum.

This study was undertaken to understand better the mechanisms causing increased milk protein. Cows fed steam-flaked sorghum have increased milk protein compared with that of cows fed dry-rolled sorghum because of a large shift of starch digestion from the intestine to the rumen. Five cannulated lactating cows were infused with glucose in the rumen or with propionate in the duodenum in two trials. The experimental design was a 2 x 2 Latin square with 7 d of adjustment and 7 d of infusion. During the experiment, cows received a TMR containing 19.3% CP and 1.56 Mcal/kg of NEL (on a DM basis); alfalfa hay and dry-rolled sorghum grain were the principal ingredients. Similar concentrations in feces of cows among propionate treatments suggested complete absorption of infused propionate. Milk yield did not differ, but protein percentage of milk was higher (2.88 versus 2.72%) for cows infused ruminally with glucose than for those infused in the duodenum with propionate. For the respective treatments, duodenal flows were 2.11 and 1.76 kg/d for microbial protein and 3.44 and 2.73 kg/d for total CP (or 85 and 74% of CP intake). These data demonstrate that increased propionate availability for gluconeogenesis and a possible sparing of essential AA did not result in increased milk protein content, but ruminal infusion of glucose, which tended to increase microbial protein synthesis, did increase the protein percentage of milk.

Adenosine Triphosphate

Effect of source and amount of supplemental fat on lactation and digestion in cows.

Thirty Holstein cows averaging 50 DIM were assigned to five dietary treatments for 75 d to determine the effects of source and amount of supplemental fat on milk yield, milk composition, and nutrient digestibilities. Diets were 1) control, 2) diet 1 plus 12% whole cotton-seed, 3) diet 2 plus 2.2% safflower oil, 4) diet 2 plus 2.2% prilled tallow fatty acids, and 5) diet 2 plus 4.4% prilled tallow fatty acids. Milk yield was increased an average of 2.1 kg/d by addition of 2.2% prilled tallow fatty acids or safflower oil to the diet (7% fatty acids) containing 12% whole cottonseed. However, when fatty acids were increased to 9.1% with additional prilled tallow fatty acids, milk yield, DMI, and fatty acid digestibility decreased. Whole cottonseed alone and in combination with all fat additions decreased milk protein concentrations. Safflower oil increased C18:0, C18:1, and C18:2 fatty acids in milk. Digestibilities of OM, NDF, and ADF were not affected by diet. Supplementation of a saturated or unsaturated fat source to increase fatty acid content to 7.0% of dietary DM increased milk yield, but a further increase in fat to 9.1% with the saturated source appeared excessive for cows yielding 30 to 35 kg/d of milk.

Animals

Heat stress interactions with protein, supplemental fat, and fungal cultures.

Cows that were subjected to hot environmental temperatures yielded less milk (3.1 kg/d) on a diet high in CP (18.4%) and of medium degradability (65%) than on diets high in CP of low degradability (59%) or medium in CP (16.1%). The high CP diets were associated with decreased DMI and higher water intake, ruminal NH4, and blood urea. Negative effects on yield from the high CP, medium degradability diet were not observed at moderate temperatures. Evaporative cooling of cows in hot weather resulted in a greater milk yield response to low versus medium rumen-undegradabale protein diets than for uncooled cows. Evaporative cooling of cows also affected response to protein quality. For cooled cows, high Lys diet (soybean, fish, and blood meals) increased milk yield 14% over that with low Lys diet (corn gluten meal), but, for uncooled cows, a high Lys diet only increased yield by 9%. Percentage of CP, degradability, and protein quality had no effect on body temperatures or respiration rates of lactating cows. Some, but not other, reports showed that supplementation of 2 to 2.5% fat to diets fed under hot summer conditions resulted in less yield response than when fat was added at moderate temperatures. In several studies, fungal cultures (3 to 5 g/d) in the diet decreased body temperatures and respiration rates in hot, but not cool, weather. Increased milk yields and cellulose digestibility also resulted from dietary fungal cultures in some, but not all, trials. The mechanism of action exerted by fungal cultures on body temperature and respiration rate is unclear.

Animal Feed

Evaluation of chemical and physical properties of feeds that affect protein metabolism in the rumen.

The goal of the NC-185 Cooperative Regional Research Project is to provide the information needed to improve the nutrition and feeding of dairy cattle, a major factor determining composition of milk and cost of milk yield. Emphasis is placed on understanding how energy and protein nutrition of lactating cows can be manipulated to increase the quantity and improve the profile of AA passing to the small intestine and to improve yield of milk and milk protein. To achieve this goal, one of the major objectives of this project has been to evaluate quantitatively the chemical and physical properties of protein and energy sources that determine AA availability to lactating cows. Reliable measurements of microbial protein synthesis and protein degradation in the rumen are critical in the evaluation process. Therefore, one of the ongoing areas of investigation of this research project has been to determine the most appropriate methods for estimating microbial protein synthesis and dietary protein degradation in the rumen. Other areas have been investigated, using continuous culture fermenters and ruminally and duodenally cannulated cows, including factors that alter microbial metabolism of N in the rumen and subsequently protein supply to the small intestine, such as sources of carbohydrate, protein, and fat and interrelationships of protein and carbohydrate. Findings of the NC-185 Cooperative Regional Research Project Committee and other investigators are summarized in this review.

Animal Feed

Comparison of digestibility, nutritive value, and storage characteristics of different forms of cottonseed in diets fed to lactating dairy cows.

Thirty-two Holstein cows averaging 70 d postpartum were used to compare digestibility of whole short staple cottonseed (SS) to whole Pima (WP), coarsely cracked Pima (CrP), and ground Pima (GP) cottonseeds and their effects on lactational performance. Cottonseed was fed at 15% of diet DM. Milk and solids-corrected milk (SCM) yields were higher for cows fed GP than for cows fed CrP or WP but were not different from yields of cows fed SS. Feed efficiency (SCM/DMI) was higher for cows fed GP and SS than for those fed WP. Milk of cows fed GP was lower in stearic acid but higher in linoleic and linolenic acids than milk of cows fed SS. Whole seeds passing into the feces (percentage of consumed) were higher for WP (12.3%) than for SS (6.2%). Total tract digestibility of ether extract was lower for WP than for other diets. Digestibilities of other nutrients were not different. To test storage characteristics, samples of cottonseed were incubated at 32 degrees C and 30% relative humidity for 0, 10, 20, and 30 d, or stored at ambient temperatures in covered buckets for 9 mo. No differences in amount of free fatty acids between incubated samples were noted, and only CrP stored in buckets for 9 mo was significantly higher in free fatty acids than initial or frozen seed. No differences in aflatoxin were detected, and levels were very low. Milk yield of cows fed GP diets was similar to that of cows fed SS diets and slightly higher than those of cows fed CrP or WP diets. Processing the Pima seed increased feed efficiency.

Animal Feed