Effect of yeast with bacteriocin from rumen bacteria on laying performance, blood biochemistry, faecal microbiota and egg quality of laying hens.

The purpose of this study was to evaluate the effect of yeast with bacteriocin from Ruminococcus albus 7 (albusin B) on physiological state and production performance of laying hens. One hundred and twenty 26-week-old Single Comb White Leghorn (Hyline) laying hens were assigned into five groups including: (i) control group, (ii) yeast control (YC), (iii) 0.125% yeast with bacteriocin (0.125B), (iv) 0.25% yeast with bacteriocin (0.25B) and (v) 0.5% yeast with bacteriocin (0.5B). All supplements were added to the experimental diets of the hens from 26 to 46 weeks of age. Samples were collected every 4 weeks. Blood samples were collected from the wing vein for blood biochemical parameters assay, and faecal samples were collected by swab for the microbiota test. The egg production performance was recorded daily, and fresh eggs were collected for quality test. The blood biochemical assay results indicated that the addition of yeast with bacteriocin decreased the AST (aspartate aminotransferase) activity and it also affects the lactate concentration in laying hen blood. The result of egg quality indicated that yeast with bacteriocin supplementation had no effect on the mass of yolk and the strength of eggshell, but it had positive effect on the laying performance under hot environment. Low concentration bacteriocin (0.125B) supplementation could decrease total yolk cholesterol. The faecal microbiota result indicated that the supplementation of bacteriocin increased the lactobacilli counts. The yeast with bacteriocin supplementation significantly decreased the clostridia counts under hot environment condition, especially in hens receiving 0.25B. Combining the data from clinic chemistry, faecal microbiota, egg production and egg quality, the 0.25B supplementation may result in the best physiological parameter and egg production performance of laying hen.

Identification of risk factors of Coxiella burnetii (Q fever) infection in veterinary-associated populations in southern Taiwan.

The first case of Q fever in Taiwan was reported in 1993. The disease is considered to be emerging in Taiwan, but the route of transmission has remained unclear. The annual number of confirmed Q fever cases has been increasing up to more than 100 cases since 2005, comparing with less than 30 before 2003. The purpose of this study was to determine the seroprevalence and risk factors of Coxiella burnetii infection in veterinary-associated populations in southern Taiwan. A total of 228 serum samples of high risk individuals engaging in veterinary-related work or animal-farm work, were collected between March and June in 2007. The study individuals were interviewed by a structured questionnaire designed for Q fever investigation. Serum samples from different animal species were also obtained for Q fever analysis in the same study areas. Serological test was conducted by indirect immunofluorescence antibody assay (IFA). The result demonstrated the overall seroprevalence of Q fever was 26.3% in individuals engaging in veterinary and animal-related work in southern Taiwan. After multiple logistic regression analysis, goat exposure was significantly associated with seropositivity of Q fever in the study population in southern Taiwan (adjusted odds ratio: 2.62; 95% CI: 1.06-6.46). In addition, the highest seroprevalence (43.8%) of Q fever was identified in goats (P < 0.05). Finally, this study documented that people with prior knowledge of Q fever were less likely to be seropositive for C. burnetii. It was concluded that goat exposure was the most important risk factor associated with C. burnetii infection and appropriate health education could be useful to prevent high risk individuals from the infection in southern Taiwan.

Hepatitis A virus infection in Taipei in 1999.

BACKGROUND AND PURPOSE: Hepatitis A is a disease that is heavily affected by sanitation status. Hepatitis A is much less prevalent compared with decades ago in Taiwan, as in many rapidly developing regions. Hepatitis A vaccine is still self-paid under the National Health Insurance program and is still not widely utilized by the general public in Taiwan. This seroepidemiologic study evaluated the prevalence of antihepatitis A virus (anti-HAV) seropositivity in Taipei in 1999. METHODS: A total of 1017 serum samples from healthy inhabitants in Taipei were examined for anti-HAV antibody by qualitative enzyme immunoassay. RESULTS: The overall seroprevalence rate was 25.2% (255/1013) in the nonvaccinated population. The seropositivity rate for anti-HAV antibody among children younger than 12 months old was 23.3%. The rates dropped to between 1% and 4.8% among subjects between 1 and 20 years of age. A markedly higher rate of 40% was observed in subjects aged between 20 and 30 years. The seropositivity rate in subjects aged 31 to 50 was 80%. More than 90% of subjects older than 50 years were seropositive. The vaccination rate was low (0.5%). CONCLUSION: Our findings indicate that Taipei is an area of intermediate endemicity for hepatitis A virus. To achieve better herd immunity, a more active approach to the adoption of hepatitis A vaccine is warranted.

Monte Carlo simulations of the nucleation and growth process of colloidal particles.

We have examined the effect of the total initial monomer concentration and that of the monomer-monomer attraction energy on the nucleation and growth process of colloidal particles using a reversible aggregation model (Shih-Aksay-Kikuchi model) with the Monte Carlo method. We showed that the equilibrium monomer concentration c(e) exhibited a peak with respect to the total initial monomer concentration c(t). Furthermore, the solution may be divided into three regimes with respect to c(t). In the first regime where the initial monomer concentration was low, all monomers remained as individual monomers in the solution and c(e) increased linearly with c(t). In the second regime where small clusters of monomers began to form, c(e) underwent a peak with respect to c(t). In the third regime where large particles form, c(e) slowly decreased with c(t). Moreover, with increasing monomer-monomer attraction energy, the peak in c(e) moved to a lower c(t) and became sharper. The equilibrium monomer concentration surrounding a particle with respect to particle size was shown to agree with the Kelvin equation, indicating that the model can indeed capture the equilibrium solution physics involving colloidal particles. The peak exhibited in c(e) versus c(t) was manifested as a peak in the monomer concentration versus time under conditions where monomers were gradually fed to the solution. The present simulation is a simulation model for illustrating a peaked solute concentration with respect to time first proposed by LaMer and Dinegar. We further showed that the supersaturation peak in the monomer concentration versus time depended on the feeding rate. The peak height increased with an increasing feeding rate.

Pneumoconiosis and pulmonary function defects in silica-exposed fire brick workers.

This study was conducted to investigate the health effects of exposure to silica dust in firebrick manufacturing plants. A cross-sectional study was designed, and the health effects in 526 exposed workers were compared with 164 nonexposed control workers. The medical examination included chest x-rays, pulmonary function tests, and a respiratory symptom questionnaire. Radiological evidence of pneumoconiosis was evident in 6.9% of the exposed firebrick workers, and the prevalence of pneumoconiosis increased with duration of employment. No differences in forced vital capacity were noted between the exposed and control groups; however, in both smokers and nonsmokers of the exposed group, forced expiratory flow in 1 s/forced vital capacity, mean maximal expiratory flow, forced expiratory flow at 50% vital capacity, and forced expiratory flow at 75% vital capacity were significantly lower than in the control group. Pulmonary function decreased as the duration of employment increased. The exposed group experienced significantly more wheezing, compared with the control group. There was evidence of a dose-response relationship between prevalence of pneumoconiosis/pulmonary function defects and estimated dust exposure levels. Pneumoconiosis and pulmonary function defects occurred frequently in workers who participated in the crushing and burning operations, both of which cause exposure to high levels of silica dust. We concluded that exposure to silica dust in workers at firebrick factories leads to radiological changes, pneumoconiosis, and pulmonary function damage.

Elution of kidney-bound antibody by pH-shift does not discriminate between antibodies differing in functional affinity for their ligand.

Antibodies eluted from kidneys by traditional methods of pH shift have been used as reagents in a wide variety of experimental analyses without knowledge of whether their ligand affinity influenced their removal from parenchymal tissue. In the current study we employed two monoclonal antibodies, differing only in their functional affinity (high; K = 2.1 x 10(8)/M and low; K = 6.2 x 10(6)/M) to a common ligand found on the renal basement membrane, to evaluate whether a standard elution technique might selectively facilitate the removal of one antibody over the other. Our findings indicate, however, that the routine methods of elution by pH shift remove both antibodies equally well (41-48%), and without loss of paratypic function. These results provide new evidence that elution by pH shift can produce eluate antibodies which are not biased by preferred affinities.