EPIDEMIOLOGY OF SALMONELLA CONTAMINATION OF POULTRY MEAT PRODUCTS: KNOWLEDGE GAPS IN THE FARM TO STORE PRODUCTS

The ultimate goal of controlling foodborne hazards is to reduce the risk of disease to consumers, and the economic burden related to foodborne illness. A literature review identified four areas of insufficient data on the epidemiology of Salmonella. A cross-sectional study was used to estimate prevalence of enteric bacterial contamination of plant-based animal feed and milk replacer from Maryland and Northern Virginia. All samples were negative for Campylobacter; 0.6% were positive for Salmonella; 5.7 % for E.coli; and 50.6% for Enterococcus. Samples purchased in summer of 2002 were 38 times more likely to be contaminated with Enterococcus than samples purchased in winter of 2002 (p-value<0.001). Enterococcus positive samples were 8 times more likely to be E.coli positive than Enterococcus negative samples. Another cross-sectional study was used to assess the association between the pattern of airflow and the distribution of fecal coliforms and Salmonella in commercial chicken litter. At moderate relative humidity (about 50%), there was a significant association between regions of reduced airflow and increased coliform and Salmonella contamination within a poultry house. An analysis of a PCR technique to validate sensitivity and specificity relative to culture techniques for detecting Salmonella contamination in retail poultry meat was conducted. When only BPW pre-enrichment was used, the PCR test had a sensitivity of 85%. This increased to 89 - 100% when BPW pre-enrichment was followed by selective enrichment with RV or TT-H broth, respectively when conventional culture is the gold standard. A minimum of 12 hours pre-enrichment and 100 cfu was necessary to achieve 100% sensitivity with PCR. Random poultry meat samples from 10 retail grocery outlets in Maryland were collected in the final cross-sectional study. Overall Salmonella prevalence in poultry meat products was 23% (C.I 15.16 - 30.86). Integrator brand ground chicken meat had an increased Salmonella prevalence compared to non-ground meat products; however this difference was not significant (p=0.0533). Store brand non-ground chicken meat products were 18 times more likely to be contaminated with Salmonella than integrator brands (C.I. 5.41-61.26)

Effect of seminal plasma removal, washing solutions, and centrifugation regimes on boer goat semen cryopreservation

Three experiments were carried out to improve semen quality during cryopreservation process. Total motility, forward motility, acrosome integrity, live spermatozoa, and normal spermatozoa were measured as semen quality. In Experiment 1, the effects of seminal plasma removal were analyzed by using two different extenders (GE and FE). The removal of seminal plasma gave higher and significant (P<0.05) effect in the total motility, forward motility, and live spermatozoa after cryopreservation. For two different extenders, however, the differences were not observed on the semen quality. In Experiment 2, three different washing solutions (namely, phosphate buffered saline, normal saline and Tris-based extender) were tested to evaluate the effects of semen quality after cryopreservation. Tris-based extender (TCG) conferred the highest (P<.05) sperm quality values in the total motility, forward motility, and live spermatozoa after cryopreservation. In Experiment 3, the effects of different centrifugation regimes (3000 × g for 3 min, 1600 × g for 10 min, 800 × g for 15 min) were evaluated on Boer semen quality. Semen quality parameters (namely, total motility, forward motility, acrosome integrity, and live spermatozoa) were significantly (P<.05) higher for cryopreserved spermatozoa centrifuged with 3000 × g for 3 min than the others. In conclusion, the removal of seminal plasma, washing solution TCG, and the use short-term centrifugation with a relative high g-force could contribute to the increased Boer semen quality after cryopreservation

Considerations for studying transmission of antimicrobial resistant enteric bacteria between wild birds and the environment on intensive dairy and beef cattle operations

Background Wild birds using livestock facilities for food and shelter may contribute to dissemination of enteric pathogens or antimicrobial resistant bacteria. However, drivers of microbial exchange among wildlife and livestock are not well characterized. Predisposition for acquiring and retaining environmental bacteria may vary among species because of physiologic or behavioral differences, complicating selection of a bacterial model that can accurately characterize microbial connections among hosts of interest. This study compares the prevalence and antibiotic resistance phenotypes of two potential model bacterial organisms isolated from wild birds and their environments. Methods We compared prevalence and resistance profiles of Escherichia coli and Enterococcus species isolated from environmental swabs and bird feces on a residential control site, a confinement dairy, a pasture-based beef farm, and a confinement beef farm. Results Bird feces at all sites had low-to-moderate prevalence of Escherichia coli (range: 17–47%), despite potential for exposure on farms (range: 63–97%). Few Escherichia coli were isolated from the control environment. Enterococcus faecalis was dominant in birds at both beef farms (62% and 81% of Enterococcus isolates) and low-to-moderately prevalent at the dairy and control sites (29% and 23% of isolates, respectively). Antimicrobial resistance prevalence was higher in farm samples compared to those from the residential control, but distribution of resistant isolates varied between the bacterial genera. Birds on all farms carried resistant Enterococcus at similar rates to that of the environment, but resistance was less common in bird-associated Escherichia coli despite presence of resistant isolates in the farm environment. Discussion Bacterial species studied may affect how readily bacterial exchange among populations is detected. Selection of microbial models must carefully consider both the questions being posed and how findings might influence resulting management decisions

Effect of sugars on characteristics of Boer goat semen after cryopreservation

In order to improve Boer goat semen quality during cryopreservation process, the influence of sugar supplementation on semen characteristics of sperm were investigated. Three experiments were carried out to investigate the effect of (a) addition of two monosaccharides (fructose and glucose) and two disaccharides sugars (trehalose and sucrose) (b) sugar combination (fructose and trehalose, sucrose and trehalose, glucose and trehalose), and control (glucose without trehalose) (c) different concentrations of trehalose on cryopreservation using Tris based extender. The total motility, forward motility, viability, normal spermatozoa, acrosome integrity and membrane integrity were assessed subjectively. Differences were not detected among monosaccharides, but glucose increased (P 0.05) among disaccharide sugar supplementation. Combination of glucose and trehalose significantly improved the characteristics of Boer spermatozoa after cryopreservation (P < 0.05). Supplementation of trehalose (198.24 mM) into the glucose extender significantly increased total motility, forward motility, live spermatozoa, acrosome integrity and membrane integrity following cryopreservation (P < 0.05). In conclusion, glucose had the better ability to support Boer sperm motility and movement patterns. Combination of monosaccharide (glucose) and disaccharide (trehalose) improved semen quality following cryopreservation. Trehalose supplementation at the concentration of 198.24 mM to the glucose extender conferred the greater improvement of semen quality for Boer semen cryopreservation

New Record on the Occurrence of Cyst Nematode, Heterodera cajani Koshy, 1967 on Sesame, Sesamum indicum in Myanmar

Sesame, Sesamum indicum L. occupies for nearly half of the area sown to oilseed crops in Myanmar. It is cultivated for domestic consumption and export. During 2003, sesame cultivars, Sinyadnar3, Sinyadanar5, Magway7/9 and Khwaylayni grown in Oilseed Crop Research Farm, Department of Agricultural .Research, Magway were found to be heavily infected with Heterodera cyst nematodes. In 2004, cysts were also found from the soil samples collected from the previously infested plots. Infested field showed patches in which the plants were stunted, chlorotic, and caused wilting. When the infected plants were uprooted, curving of tap root, and red-girdling and dark browning of lateral and tap roots were observed. Lemon-shaped cysts were found attaching to the root surface. Young females were white or creamy colour whereas old cysts with eggs were tan colour. A few bullae were found on the posterior portion of the female. Larvae were vermiform with elongate conoid tail. Males were cylindrical or elongated with short tail without bursa. According to the morphological characters of the nematode and disease symptoms of sesame, the nematode was supposed to be identified as Heterodera cajani. There was no report o cyst nematode, Heterodera spp. in Myanmar. The present finding, the occurrence of Heterodera cajani on sesamum, is the first record of Heterodera spp. in Myanmar