Growth performance, meat quality, and gut microflora of broiler chickens fed with cranberry extract.

Cranberry fruit components have been reported to have antimicrobial activities against a variety of pathogenic bacteria and to be beneficial for human health. Studies on their effects are very limited in animals and especially in chickens. This study investigated the effect of feed supplementation with a commercial cranberry fruit extract (CFE) on the performance, breast meat quality, and intestinal integrity of broiler chickens. Twelve hundred male 1-d-old broiler chicks were allocated randomly to CFE treatments at 0, 40, 80, or 160 mg/kg of feed from d 0 to 35. Cloacal and cecal samples were collected weekly to evaluate the influence of treatments on the intestinal population of generic Escherichia coli, Clostridium perfringens, Enterococcus spp., and Lactobacillus spp. At d 35, BW were 1.62, 1.60, 1.61, and 1.64 kg for the control birds and birds fed 40, 80, and 160 mg of CFE/kg of feed, respectively. Feed intake ranged from 2.7 to 2.8 kg and feed efficiency from 1.8 to 1.9 g of feed/g of BW. However, the treatment effects on bird performance were not statistically significant (P > 0.05). The mortality rate tended to be lower (P = 0.09) in birds fed 40 mg of CFE/kg of feed. Feed supplementation with CFE did not significantly alter any broiler meat properties evaluated when compared with the control diet (P > 0.05). At d 28, the populations of Enterococcus spp. in cecal and cloacal samples were significantly lower (P < 0.05) in birds receiving CFE at 160 mg/kg of feed than the other groups. No significant differences were noted between the control and the treatment groups for general health and intestinal integrity (P > 0.05). These findings suggest that more studies are needed to investigate potential beneficial effects of CFE or its derivatives in broiler production.

Flesh quality of market-size farmed and wild British Columbia salmon.

This study compared the flesh quality of farmed and wild sources of British Columbia (BC) salmon with respect to concentrations of polychlorinated biphenyl compounds, polychlorinated dibenzodioxins/dibenzofurans and their associated toxic equivalents, total mercury (THg), methylmercury (MeHg), and selected fatty acids of known importance for human health viz., omega-3 (n-3) highly unsaturated fatty acids (n-3 HUFAs) and (n-6) fatty acids. Skinned fillets from known sources of farmed Atlantic, coho, and chinook salmon (n = 110) and wild coho, chinook, chum, sockeye, and pink salmon (n = 91) were examined. Atlantic salmon contained higher PCB concentrations (means, 28-38 ng/g) than farmed coho or chinook salmon, and levels in these latter species were similar to those in wild counterparts (means, 2.8-13.7 ng/g). PCB levels in Atlantic salmon flesh were, nevertheless, 53-71-fold less than the level of concern for human consumption of fish, i.e., 2000 ng/g as established by Health Canada and the U.S. Food and Drug Administration (US-FDA). Similarly, THg and MeHg levels in all samples were well below the Health Canada guideline (0.5 microg/g) and the US-FDA action level (1.0 microg/g). On average, THg in farmed salmon (0.021 microg/g) was similar to or lower than wild salmon (0.013-0.077 microg/g). Atlantic salmon were a richer source (mean, 2.34 g/100 g fillet) of n-3 HUFAs than the other farmed and wild sources of salmon examined (means, 0.39-1.17 g/100 g). The present findings support the recommended weekly consumption guidelines for oily fish species (includes all BC salmon sources) for cardio-protective benefits as made by the American Heart Association and the UK Food Standards Agency.

Solid phase microextraction/gas chromatography of Salmonella-infected beef.

Eight strains of Salmonellae were incubated in TSB culture medium at 37 degrees C for 24 h. Volatile compounds derived from the bacteria were collected using solid-phase microextraction fibers and then applied to gas chromatography (GC). Similarity analysis of the GC patterns thus obtained could separate these strains on principal component similarity (PCS) scattergrams. Five major food-related pathogenic bacteria and 10 other bacteria (including one Salmonella strain) were also classified by growing in the same medium. It is then proposed to utilize this approach to improve the GC/PCS method of Nakai et al. [Nakai, S.; Wang, Z. H.; Dou, J.; Nakamura, S.; Ogawa, M.; Nakai, E.; Vangerstoep, J. J. Agric. Food Chem. 1999, 47, 576-583] that has been developed for screening safe foods by detecting bacteria contaminated foods. Inoculating food samples pre-enriched through preliminary incubation into a culture medium and then subjecting to the GC/PCS method after secondary incubation enhances the detectability of pathogenic bacteria.

Nutritional profile and antimicrobial spectrum of the spice Aframomum danielli K. Schum.

The spice, Aframomum danielli, on a wet weight basis with a moisture content of 10.5%, protein content of 8.2% (dry matter basis) and caloric value of 469.7 kcal/100 g, contains in varying amounts, minerals like calcium, magnesium, sodium, manganese, phosphorus, zinc and copper. Amino acids found in varying concentrations in A. danielli include L-Threonine, L-Serine, L-Valine, L-Proline, L-Glutamic acid, glycine, L-Leucine and L-Lysine. Using minimum inhibition zone of 20-22 mm in diameter, A. danielli inhibited the growth of Salmonella enteriditis, Psudomonas fragi, Pseudomonas fluorescens, Proteus vulgaris, Streptococcus pyogenes, Staphylococcus aureus, Aspergillus flavus, A. parasiticus, A. ochraceus and A. niger. The minimum concentration (MIC) determined for Klebsiella pneumoniae and Pseudomonas aeruginosa was 1 in 320 whilst the MIC for S. aureus was 1 in 8,000.

Structure of the glycocalyx polysaccharide of Pseudomonas fragi ATCC 4973.

The structure of the exocellular glycocalyx polysaccharide of Pseudomonas fragi ATCC 4973, a bacterium implicated in the spoilage of meat, has been determined using hydrolysis, methylation analysis and 1D- and 2D-n.m.r. spectroscopy. The polysaccharide, which aids in the adhesion of the cells to each other and to the meat tissue, has the regular repeating unit ----4)-3-O-[(R)-1-carboxyethyl]-alpha-D-Glcp-(1----3)-beta-D-ManpNAc+ ++- (1----4)-beta-D-Glcp-(1----. Random partial O-acetylation occurred in some preparations of the polysaccharide.

Centroid search optimization of cultural conditions affecting the production of extracellular proteinase by Pseudomonas fragi ATCC 4973.

The production of extracellular proteinase by Pseudomonas fragi ATCC 4973 grown in a defined citrate medium, containing glutamine as the sole nitrogen source, was determined under varying cultural conditions. Simultaneous evaluation of cultural conditions using a 'centroid search' optimization technique showed that the optimum cultural conditions for proteinase production by Ps. fragi were: incubation temperature, 12.5 degrees C; incubation time, 38 h; initial pH, 6.8; organic nitrogen concentration, 314 mmol nitrogen/l (glutamine); a gas mixture containing 16.4% oxygen flowing over the medium (7.42 ppm dissolved oxygen). Oxygen was the major factor influencing proteinase production by Ps. fragi. The results may have applications in the storage of fluid milk. Centroid search optimization was shown to be suitable for microbiological experiments.

Identification of proteolytic pseudomonads isolated from raw milk.

Proteolytic pseudomonads isolated from raw milk were classified by numerical taxonomy. Unweighted pair-group average-linkage cluster analysis was used to cluster 49 bacterial strains, of which 26 were Pseudomonas species, as described in the Bergey's Manual of Determinative Bacteriology, based on 52 characters. The milk isolates resided in two clusters; one containing Pseudomonas fluorescens and the other Pseudomonas fragi. The isolates identified with Pseudomonas fluorescens hydrolyzed milk proteins and milk fat and produced phospholipase. The Pseudomonas fragi-like isolates hydrolyzed milk proteins and milk fat but did not produce phospholipase and fluorescent pigment. The hydrolytic characteristics of milk isolates showed that the nature of the substrate and conditions under which the test was conducted were critical.

Scanning electron microscope study of Pseudomonas fragi on intact and sarcoplasm-depleted bovine longissimus dorsi muscle.

Intact bovine longissimus dorsi muscle strips used 24 h postmortem were washed to remove sarcoplasmic fluid or left intact and were either left uninoculated or inoculated with Pseudomonas fragi ATCC 4973. The effects of decreased sarcoplasm concentration on growth of P. fragi and consequent microstructural changes of beef muscle during aerobic storage at 4 degrees C for 12 days were evaluated. P. fragi grew slower on washed muscle than on intact muscle. Scanning electron micrographs revealed surface degradation of both intact inoculated and washed inoculated muscle only in areas of localized colonization. Extracellular fibrils appeared to mediate adhesion of P fragi to the muscle surface as well as cell-to-cell attachment within microcolonies. P. fragi was also observed growing between muscle fibers.

Rapid Method for Detection and Quantitation of Lipid Soils on Food Contact Surfaces: Evaluation of a Model System.

A rapid method for detection and quantitation of lipid-containing food soils on food-contact surfaces has been developed to ascertain whether these surfaces have been properly cleaned. The method is based on transfer of lipid-based soils from a food-contact surface to a polyethylene film and subsequent quantitation of the lipid, at 1750 cm-1, by infrared spectrophotometry. Peak height at 1750 cm-1 is linearly related to the quantity of lipid on the polyethylene surface. Standard curves for peak-height against lipid distribution on the polyethylene film were constructed for stainless steel, glass and three types of plastic cutting board material (high density polyethylene, smooth nylotrol and rough nylotro).

Relationship Between Incidence of Salmonella Contamination Among Pre-scalded, Eviscerated and Post-Chilled Chickens in a Poultry Processing Plant.

The incidence of Salmonella contamination in 11 flocks of chickens was determined at three sites within a poultry processing plant: A, before scalding; B, after evisceration; C, after chilling. The average incidence of Salmonella contamination of flocks ranged from 1.2 to 74.4%, and flock to flock variability among sites was significant. Incidences of Salmonella ranged from 3 to 96% at site A; 0 to 69% at site B; and 0 to 96% at site C. Flocks with a high incidence of Salmonella contamination at site A were also frequently contaminated at sites B and C. By generating regression equations, it was possible to predict the incidence of Salmonella at one of these sites from the incidence at the other sites. The ability to define the interdependence between internal and external Salmonella contamination of chickens provides a basis for developing effective control measures for decreasing the incidence of Salmonella -contaminated retail chickens.