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Two feeding trials were conducted with pigs to determine the effects of blueberry supplementation on plasma lipid levels and other indices of cardiovascular benefit. In the first trial, where basal diets contained a high level of plant-based components (70 % soya, oats and barley), supplementation with 1, 2 and 4 % blueberries resulted in a decrease in total, LDL- and HDL-cholesterol. The greatest reduction was observed in the 2 % blueberry-fed pigs, where total, LDL- and HDL-cholesterol were reduced 11.7, 15.1 and 8.3 %, respectively. In the second trial where basal diets contained only 20 % (w/w) of soya, oats and barley, the lipid-modulating effect of blueberries was attenuated, so that supplementation with 1.5 % blueberries reduced total cholesterol by 8 %, which occurred only in pigs whose diets had been supplemented with cholesterol (0.08 %), NaCl (0.11 %) and fructose (9 %). In the first feeding trial, blueberry supplementation had no effect on blood platelet activity. Blueberry supplementation also had no effect on the susceptibility of leucocyte DNA to oxidation in the first trial and no effect on the susceptibility of LDL to oxidation in the second trial. Results of these two feeding trials are discussed in relation to the effects of basal diet composition on lipid-modulating effects of blueberries.

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Highbush blueberries, cv 'Burlington', were treated with 22, 45, 50, or 60 degrees C water for 15 or 30 s along with an untreated control. Fruit were then stored for 0, 1, 2, or 4 wk at 0 degrees C and 2 or 9 d at 20 degrees C prior to evaluation of microbial population and fruit quality. After 4 wk of storage, the hot water treatment at 60 degrees C resulted in 92% marketable berries, followed by 90% at 50 degrees C, 88% at 45 degrees C, and 83% at 22 degrees C compared with 76% in untreated controls. Decay incidence was reduced to 0.6%, 1.2%, 1.4%, or 2.8% with 60, 50, 45, or 22 degrees C water treatments, respectively, compared with 5.1% in controls following 4 wk at 0 degrees C and 2 d at 20 degrees C. After an additional 7 d at 20 degrees C, decay in fruit treated at 60 degrees C for 15 or 30 s remained at 1.8% and 0.4%, respectively, compared to 37.4% in controls. Weight loss of berries treated with hot water was 0.4% against 3.8% in controls, and shriveled and split berries were also reduced compared to controls (P<0.001). Aerobic plate count and yeast and mold count were reduced by 0.45 to 0.7 log at 60 degrees C for 30 s. Botrytis cinerea and Colletotrichum sp. were the dominant fungal pathogens causing decay of Burlington blueberries during storage. Hot water treatments also immediately induced an increase in ethanol and reduced fruit titratable acidity and soluble solids content, but had no significant effect on fruit firmness, pH, or most flavor volatile concentrations.

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AIMS: To investigate the effects of ozone on inactivation of Listeria innocua on solid media. METHODS AND RESULTS: Suspensions of L. innocua ranging from 4.5 x 10(4 )- 6.4 x 10(4) CFU ml(-1) were inoculated onto potato dextrose agar (PDA, pH 5.6 and 6.8) and nutrient agar (NA, pH 6.0 and 6.8), then exposed to gaseous ozone. Variable factors included postinoculation standing time at 20 degrees C before exposure to ozone, ozone concentration, treatment duration and treatment temperature (5 or 20 degrees C). The interaction among ozone concentration, treatment duration, media and temperature in effecting changes in colony-forming units (CFU) was significant. The 100 nl l(-1) ozone treatment for 2 h reduced the microbial populations by 2-3 log CFU ml(-1). Cell viability decreased more rapidly on PDA than on NA. The average time to obtain a 2 log CFU ml(-1) reduction was 1.3 h at 20 degrees C and 2.5 h at 5 degrees C (P < 0.001). CONCLUSIONS: Gaseous ozone effectively inactivates L. innocua at concentrations of 50 and 100 nl l(-1) during short exposure times at both 5 and 20 degrees C. The Gompretz model can be utilized for determining the response of L. innocua to ozone over time. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides useful information on ozone inactivating Listeria spp., which may be imposed on ensuring quality and safety of horticultural produce and food products.

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Economic control of Rhagoletis mendax was achieved by applying insecticidal sprays to commercial lowbush blueberry vegetative fields, in a biennial production system, rather than to the fruiting fields, when the threshold was exceeded. The viability of this integrated pest management of R. mendax for lowbush blueberries was demonstrated over a 9-yr interval in New Brunswick where three sites were monitored for 2 yr, eight sites for 4 yr, and one site for 9 yr. Control of R. mendax in lowbush blueberry fields was achieved in 2 yr when the fields were isolated, and in 3 yr when there were adjacent lowbush blueberry fields.

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Number of Pratylenchus spp. (primarily P. penetrans) were recorded at planting in experimental potato plots over a 9-year period at one location on Prince Edward Island. Tuber yields of 'Superior' and 'Russet Burbank' potatoes in plots treated with aldicarb were compared with yields in adjacent untreated plots. There was a linear relationship between the number of root lesion nematodes at planting and tuber yield increases after treatment for Superior, but not for Russet Burbank (P < 0.05). When counts of root lesion nematodes were greater than 500/kg dry soil, however, the tuber yields of Russet Burbank increased in treated plots. Additional trials at other locations and the inclusion of other cultivars are needed to make numerical relationships of this type available to a nematode advisory service.

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A factorial experiment involving 1,404 day-old Shaver broiler chicks (702 of each sex) assessed the effects of total calcium (Ca) and available phosphorus (AP) and their ratio (Ca: AP) during the starter (0 to 21 days) and finisher (22 to 42 days) periods on general performance, tibia strength, tibia ash, Ca and P content of tibia ash, tibia dyschondroplasia, twisted legs, and total leg abnormalities. Nine starter and nine finisher diets were used with the percentage Ca and AP ranging from .98 to 1.47 and .39 to .67, respectively, for the starters and from 1.00 to 1.40 and .32 to .51, respectively, for finishers. In general, optimum weight gain, live body weight, feed conversion, tibia strength, tibia dry weight, and tibia ash were obtained when the highest Ca + P was fed, but lower Ca:AP ratios were also effective for some traits. Tibial dyschondroplasia (TD) and total leg abnormalities, however, were highest when these diets were fed. The results indicate that the ratio of Ca:AP in the diet is a determining factor in causing TD in broiler chickens. As the ratio of Ca:AP in the diets widened in response to increased Ca or decreased P, the incidence of TD and total leg abnormalities decreased (P less than .05).

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A total of 2000 commercial chickens (1000 males and 1000 females) were used in an exploratory experiment designed to estimate the effect of two daily feed denial treatments (8 and 12 hr) extended from either 8 to 21 days or 15 to 28 days of age. Mortality was unaffected by these treatments. Body weight at 28 days was reduced, and feed conversion was improved by the feed denial treatments. The length of the daily feed denial period showed a greater impact than age of imposition, and the 12-hr daily denial time diminished the growth performance. At 49 days body weight and monetary returns were higher for the chickens exposed to the 8-hr daily feed denial treatment extending from 8 to 21 days compared with the control group (P less than .10).

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An experiment involving 7200 male broiler chickens was conducted to estimate the effect of feeding crumble-pellet diets on the incidence of Sudden Death Syndrome (SDS). Mortality due to SDS was significantly higher for birds fed a crumble-pellet regimen in its usual form or in a ground form compared with birds fed all-mash diets. Birds fed the crumble-pellet dietary regimen grew more rapidly than those on either the ground crumble-pellet regimen or on all-mash. There was no significant (P = .05) difference in the growth rate of the birds fed the ground crumble-pellet regimen compared with those fed all-mash. It was concluded that the higher incidence of SDS was due to some factor(s) in the pelleting process itself rather the rapid growth resulting from the higher density of pelleted feeds.

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Two experiments were conducted to study the influence of genotype and diet on general performance and incidence of leg abnormalities of commercial broiler chickens reared to roaster weight. In Experiment 1 a total of 1960 male day-old chicks of seven different commercial genotypes were housed separately in 14 pens (25.64 m2) with 140 birds per pen and fed one dietary regimen. In experiment 2, 3000 male day-old chicks of two commercial genotypes were randomly assigned to 20 pens (13.54 m2) with 150 birds per pen, and two replicate pens were fed one of the five different dietary regimens designed to promote rapid, intermediate, or slow growth. Differences (P less than .05) were observed among the genotypes tested (Experiment 1) in the incidence of mortality, leg abnormalities, live weight, and feed conversion but not for mean monetary returns per bird housed. In Experiment 2, significant differences (P less than .01) were observed among the dietary regimens tested for live weight, feed conversion, and monetary returns per bird housed. As the protein content of starters, growers, and finishers decreased, body weight decreased but monetary returned improved. Feeding the birds beyond 63 days resulted in substantial reduction in monetary returns. A dietary regimen which included starter, grower, developer, and finisher with 18, 24, 22, and 14% protein, respectively, resulted in significantly better feed conversion and a significantly lower incidence of leg abnormalities. Genotype X diet interactions were considered of no practical importance.

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Eight different vitamin mixtures were each fed to 6 replicate pens (150 birds/pen) of day-old Cobb chicks in a completely randomized design to evaluate the effect of biotin, pyridoxine, and thiamine singly or in combination and the effect of feeding these vitamins in addition to the standard vitamins at two and four times their required level on mortality and incidence of acute death syndrome (ADS) or "flip-over" of broiler chickens. Further additions of the standard vitamins and the addition of thiamine to the standard vitamin mixture significantly (P less than .05) increased 28-day live weights. The addition of biotin or thiamine significantly (P less than .05) improved feed conversion. Monetary returns were reduced for those diets involving multiple additions of vitamins due to increased feed costs. Total mortality and mortality attributed to ADS appeared to be reduced by the inclusion of additional vitamins. The inclusion of biotin alone significantly reduced total mortality (P less than .005) and mortality due to ADS (P less than .05).

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The efficiency of the Ziehl-Neelsen method for staining acid-fast bacteria was compared with that of the strip-staining procedure in which one kind of impregnated strip is used to stain the bacteria and another kind for simultaneous decolorization and counter-staining of the smear. The methods were evaluated in 1 136 duplicate smears prepared from digested sputum and 307 pairs of direct smears. The efficiency of the strip method was comparable to that of the Ziehl-Neelsen method with digested sputum; with direct smears, however, it generally depended on the quality of the smear. With thick, uneven smears, lower bacterial counts were obtained by strip staining. On the basis of this trial, the authors suggest improvement of the strip method.

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In this investigation a simple urine test for phenotyping isoniazid inactivators is evaluated. In the new method, isoniazid is artificially acetylated in urine and determined by the same colour reaction as that used for acetylisoniazid. Comparative studies showed that the test is reliable and can be performed with accuracy and ease even in poorly equipped laboratories. In contrast to other urine tests, it does not require an expensive spectrophotometer, tedious hydrolysis processing of the samples, or standard curves. The results can be read on a plain colorimeter, or even without any instrument.

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