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Biomedical subjects

E Block

Publications and source records attributed to E Block.

At least 73 records · Page 4Linked to original sources
PubMed1989

Plasmin and plasminogen in bovine milk: a relationship with involution?

A total of 774 individual milk samples were collected from 66 Holstein cows between October 1987 and April 1988. Samples were analyzed for plasmin, plasminogen, and SCC. An increase in SCC from less than 250,000/ml to more than 1,000,000/ml resulted in an increase of plasmin, plasminogen, and serum albumin by 105, 74, and 140%, respectively. Plasminogen, plasmin, and serum albumin followed similar trends that are expected for components from blood that gain access to the alveolar lumen through ruptured epithelium caused by mastitis. Increased plasmin is the direct result of this process rather than an increase in activation of plasminogen to plasmin. The plasminogen to plasmin ratio supports this interpretation, being 4.7 at 250,000 SCC/ml and 4.0 when SCC exceeded 1 million/ml. Plasmin and plasminogen concentrations were also increased during lactation to reach peak values immediately before the dry period. However, in this case, ratio of plasminogen to plasmin was 6.55 during early lactation and decreased by half to 3.29 during the latest stage, indicating that considerable activation of plasminogen to plasmin occurred during the latter part of lactation. Mammary epithelium is not compromised at this stage, as shown by low (.8 mg/ml) serum albumin concentration in milk. Two mechanisms responsible for increased milk plasmin include influx of plasmin from blood during mastitis and increased activation of plasminogen as lactation progresses.

Animals↗
PubMed1987

Efficacy of Levamisol on milk production of dairy cows: a field study.

Twelve hundred ninety-six cows on 88 farms were alternately injected at calving with Levamisol or saline. Each farm was visited every 2nd wk from May to October to administer treatments to cows that would calve prior to our next visit and to collect fecal grab samples from cows for worm egg counts. Production records were collected for each cow for their first 6 mo of lactation. Fecal worm egg counts were reduced in cows treated with Levamisol for the first 2 mo postcalving. Daily milk produced was higher in cows treated with Levamisol by 1.24 kg. Milk fat and protein percentages were not different between treatment groups; however, milk fat production was higher in cows treated with Levamisol for the first 2 mo post-calving. Cows treated with Levamisol produced 235 kg more milk than control cows during their first 6 mo of lactation and were projected to produce 339 kg more milk for a 305-d lactation. Month of calving improved milk production by cows treated with Levamisol. Cows treated with Levamisol and calved in months May to July showed the highest improvement in milk production while cows that were treated with Levamisol and calved in months August to October showed no significant improvement in production. Injection of cows with Levamisol at calving improves milk production and reduces gastrointestinal worm burdens.

Animals↗
PubMed1987

Ergometer modification for combined arm-leg use by lower extremity amputees in cardiovascular testing and training.

A commercial arm-leg ergometer was adapted so that combined bilateral arm-single leg work could be performed by unilateral lower extremity amputees from their own wheelchairs. Three middle-aged to elderly unilateral amputees performed progressive discontinuous bilateral arm crank and combined bilateral arm-single leg cycle exercise tests on the same air-braked ergometer adapted for either form of ergometry. Select amputees may achieve greater peak oxygen uptakes (VO2), power outputs (PO), and heart rates (HR) during combined bilateral arm-single leg cycle testing versus bilateral arm crank testing. Following 14 weeks of combined arm-leg training on the modified ergometer, a 73-year-old above-knee amputee demonstrated peak VO2 and PO increases of 25% (+3.8 mL X kg-1 X min-1) and 33% (+25W) respectively. Combined arm-leg ergometry as described herein may activate the largest available muscle mass and elicit the greatest oxygen uptake during exercise testing. In addition this exercise modality may simultaneously condition the arms and leg, providing functional gains in both wheelchair propulsion and prosthetic ambulation.

Amputees↗
PubMed1986

Efficacy of morantel tartrate on milk production of dairy cows: a field study.

Eighty Holstein herds on Quebec Dairy Herd Analysis Service were paired into 40 blocks of two herds each to test the effects of systematic deworming with morantel tartrate. Cows in treated herds were given morantel tartrate in May, June, and July, and cows in control herds were given a placebo of ground corn, wheat bran, and barley; both products were administered at 1 kg/1000 kg body weight. Records were obtained from May 1983 to April 1984. Each farm was visited monthly from May to October 1983 to obtain herbage samples and fecal grab samples from a random 10% of lactating cows. Production records were obtained for the year prior to commencement of this trial for covariate analysis. Fecal worm egg counts and infective larvae counts in pasture were reduced by 83 and 93%, respectively, in treated herds. The pattern of worm egg excretion differed between groups due to repeated treatments with morantel. Treated herds produced 323 kg more milk per cow per yr and 1.2 kg per cow per d more fat-corrected milk than controls. Milk fat and protein percentages did not differ between groups for the 12 mo. Deworming lactating dairy cows at the beginning of and during the pasture season improved production performance.

Animals↗
PubMed1985

Efficacy of morantel tartrate in a sustained release bolus on the control of subclinical gastrointestinal parasitism in first-year grazing dairy replacements.

Thirty-four heifers (24 Holstein, 8 Ayrshire, 2 Jersey) and 12 Holstein steer calves were grouped into 23 blocks of 2 animals each according to breed, sex, and body weight. Animals in each block were randomly assigned to control or treated groups. The treated group received an anthelmintic bolus containing morantel tartrate before they were permitted access to pasture. A 2.6 ha pasture was divided in half with a double fence; the resulting two pastures had separate feed and water troughs. Steer calves were slaughtered upon termination of the trial to ascertain gastrointestinal parasite burdens. Two worm-free tracer calves were placed on each pasture every 2 mo and slaughtered after 4 wk of grazing to determine parasite infectivity of pastures. Herbage samples were obtained monthly and analyzed for infective larvae. The trial was conducted for 141 d during the grazing season. Treatment resulted in 90% reduction in infective larvae on pasture, 74% reduction in fecal worm-eggs, 91% reduction in adult worm burdens, and a trend toward reduced worm burdens in tracer calves by 52%. An overall average daily gain of .68 and .88 kg was obtained for control and treated animals. Reproductive data for the heifers remaining in the herd from the trial showed that treatment resulted in 44 less days to first breeding.

Animals↗
PubMed1984

Manipulating dietary anions and cations for prepartum dairy cows to reduce incidence of milk fever.

Twenty preparturient dairy cows were in a 2-yr switchover design to test effects of dietary ions on incidence of milk fever. In yr 1, cows were blocked and assigned randomly 45 days prepartum to one of two diets; one diet contained an excess of anions, and the second diet contained an excess of cations. In yr 2, cows were changed to the opposite diet. Both diets were equivalent for crude protein (11%), calcium (.65%), phosphorus (.25%), and energy on a dry basis but differed for quantities of chlorine, sulfur, and sodium. Both diets were chopped alfalfa hay, corn silage, high moisture corn, and vitamin-mineral mix. Diets were available ad libitum as complete rations. There were no differences in dry matter intake of the diets. Cows consuming the anionic diet had no milk fever, but cows consuming the canionic diet had 47.4% incidence. Samples of blood plasma showed that cows consuming the anionic diet maintained calcium and phosphorus through parturition, whereas cows consuming the cationic diet decreased in these minerals around calving. Hydroxyproline was higher for cows consuming the anionic diet during the peripartal period compared to cows consuming the cationic diet. Milk produced in the lactation subsequent to prepartum treatment was 6.8% less for cows offered the cationic diet. When milk production of paretic and nonparetic cows offered the cationic diet was compared, milk was reduced 14% with milk fever.

Animal Feed↗
PubMed1984

Is there a "gold standard" for human serum vitamin B12 assay?

In a study from four laboratories using two commercial vitamin B12 radioassays (impure hog intrinsic factor concentrate containing both intrinsic factor and R binders (IF + R) to measure total corrinoids and the same concentrate presaturated with cobinamide (Cbi) to block B12 binding sites on R binder (IF + R + Cbi) to measure only cobalamins), the rank order of results was generally the same. The concordance between the two tests for classifying sera as normal or deficient was 91% in 311 serum samples. Three percent of sera below the "true B12" (B12 binding to IF + R + Cbi) normal cut-off point were not below the cut-off point for normal "total B12" (B12 binding to IF + R); 6% of sera below the total B12 normal cut-off point were not below true B12 cut-off point. The correlations between Euglena gracilis and the radioassays were 0.80 and 0.83 in the 50 serum samples that also had E. gracilis serum vitamin B12 levels. Lactobacillus leichmannii serum vitamin B12 levels were determined in 49 of the 311 serum samples and results were comparable with results obtained by four radioassay binder systems: IF + R, IF + R + Cbi, highly purified hog IF, and saliva R binder. The closest correlate with L. leichmannii was radioassay using IF + R as binder (r = 0.93), then IF + R + Cbi (r = 0.92), pure IF (r = 0.80), and pure R (r = 0.73). The key to reliable results appears not to reside in a particular assay but rather in determining for each assay its own range of results in participants determined clinically and morphologically normal vs. participants with deficient vitamin B12 (with B12 deficiency defined independently of a serum B12 assay). When laboratory assay results differ from clinical judgment, further evaluation is the appropriate course. There is no "gold standard" for human serum vitamin B12 assay.

Biological Assay↗
PubMed1981

Acid insoluble ash as a marker of digestibility for sheep fed corn plants or hay and for lactating dairy cattle fed hay.

Research has shown acid insoluble ash (AIA) in feeds to be an acceptable natural marker for the determination of dry matter digestibility in sheep and steers fed diets of hay plus grain. However, in previous studies, animals were fed diets designed to ensure little or no orts. The purpose of this study was to determine the adequacy of AIA as an indicator of dry matter digestibility when sheep or dairy cows were fed ad libitum. Fecal, feed and ort samples from wethers and lactating Holstein cows from previous digestibility studies were used to determine the usefulness of AIA as an indicator of digestibility. Thirty-two wethers were fed whole corn plants or corn stover frozen and stored fresh or ensiled. Diets were fed ad libitum to ensure between 5 and 10% orts. In a second study, seven wethers and 10 lactating cows fed fed ad libitum alfalfa or orchard grass hay diets with 23% grain to ensure at least 10% orts. Correlation coefficients for digestibility determined by total collection versus AIA for wethers fed corn plants, cows fed hay diets and wethers fed hay diets were .96, .95 and .40, respectively. The low correlation for wethers fed hay was apparently due to a high quantity of orts with a variable AIA content. The range of total recovery of AIA from all animals was of total recovery of AIA from all animals was 98 to 102% when ort AIA was taken into account, and 91 to 121% when ort AIA was not taken into account. The use of AIA as a natural marker for the estimation of digestibility when diets are fed ad libitum has potential, provided that a sufficient number of animals is used and diets are adequately mixed to limit feed selection and sorting, or intake is determined and feed and orts are sampled.

Animal Feed↗
PubMed1980

Woodpulp fines or corn silage as roughages in complete rations or a pelleted complete ration for young dairy replacements from birth through 18 weeks of age.

Holstein calves, 18 females and 12 males, were assigned randomly to 10 blocks of 3 calves each by sex, and within each block were assigned randomly to one of three experimental rations. All calves received sour colostrum from day 1 through day 35. The respective dry rations were offered beginning at day 8. The three rations consisted of (dry basis): 1) 11% woodpulp fines and 89% concentrate; 2) 33.7% corn silage and 66.3% concentrate; and 3) a commercially available pelleted complete ration. From birth through 8 wk, calves fed woodpulp gained more weight than those fed silage and approximately equal weight to calves fed commercial ration. From 8 through 18 wk. calves fed the latter gained more weight than other calves. Dry matter intake followed the same order as weight gain. Blood samples were obtained biweekly beginning with the 2nd wk from the jugular vein of each calf. There were no differences in glucose 2 through 18 wk. Urea nitrogen of plasma was greater in calves fed commercial ration than in other calves in six of the sampling periods. Calves fed silage had more urea nitrogen in plasma than calves fed woodpulp for three of the sampling periods. Rumen tissue from male calves at 18 wk fed woodpulp showed the most normal appearance in papillae color, density, and length. Calves fed silage had rumen tissue showing short, black, nodular papillae. Calves fed commercial ration showed long, branched, necrotic papillae that were keratotic and loosely attached.

Animal Feed↗
PubMed1980

Woodpulp fines or corn silage as roughages in complete rations or a pelleted complete ration for young dairy replacements 18 through 36 weeks of age.

Twenty-eight Holstein calves were fed one of three experimental diets from 18 through 36 wk: 1) 50% woodpulp fines, 25% corn silage, and 25% concentrate; 2) 75% corn silage and 25% concentrate; and 3) a commercially available, pelleted, total calf ration. The first two rations were equivalent in roughage, vitamin, and mineral content, and all three rations were equivalent in crude protein. Average daily gain (kg), dry matter intake (% of body weight), and feed/gain for calves fed the three rations were .92, 2.42. 6.28; 1.10, 2.29, 4.07; and 1.12, 3.16, 6.73. Glucose (mg/100 ml), urea nitrogen (mg/100 ml), and B-hydroxybutyrate (mg/100 ml) in plasma from calves at 23 wk were 72.0, 5.2, .7; 72.5, 5.1, 1.9; and 82.4, 12.3, .8. The amount of butyrate (% of total), acetate/propionate, and pH of the rumen fluid from calves at 23 wk were 6.31, 2.79, 6.99; 11.74, 2.76, 7.05; and 9.89, 2.04, 6.73. Papillae length (cm) and density/cm2 ofa the rumen tissue from male calves by biopsy were: 1.83, 48.5; 2.12, 67.1; and 2.12, 27.6. Corn silage and woodpulp fines or corn silage alone can be fed to dairy calves in complete rations with satisfactory results from 18 to 36 wk of age. Additional experimentation is required to optimize quantities and proportions of these roughages in complete rations for young heifers.

3-Hydroxybutyric Acid↗