Simultaneous detection of airborne aflatoxin, ochratoxin and zearalenone in a poultry house by immunoaffinity clean-up and high-performance liquid chromatography.

An AOZ method, based on high-performance liquid chromatography (HPLC), was optimized on HPLC condition such as mobile phase and wavelength to simultaneously quantify six kinds of mycotoxins [four aflatoxins (AFs), ochratoxin A (OTA) and zearalenone (ZEA)]. Conditions for immunoaffinity clean-up, HPLC and photo-derivatization were optimized in this study and successfully applied in assessment of airborne mycotoxins from a poultry house in Dalian, China. Fifty-two air samples were collected with AGI-30 air samplers using pure water as collection media. Twenty air samples (20/52, 38.46%) were positive for four toxins. Among the positive samples, airborne mycotoxin concentrations (mean+/-S.D.) for AFG(2), AFB(1), and ZEA were 0.189+/-0.024 (n=9), 0.080+/-0.003 (n=11) and 2.363+/-0.030 (n=5)ng/m(3) air, while the concentration for OTA was 8.530 (n=1)ng/m(3). No positive sample was found for either AFG(1) or AFB(2). A chicken may inhale 0.019-0.057 ng AFG(2), 0.013-0.019 ng AFB(1), 0.436-0.513 ng ZEA, and 1.706 ng OTA, respectively, in a day. A poultry worker may inhale 0.504-1.512 ng AFB(1), 0.752-2.28 ng AFG(2), 68.240 ng OTA, and 17.432-20.512 ng ZEA in a working day. This is the first report on airborne mycotoxins in poultry house. These data may have importance in animal and public health implications.

Staphylococcus aureus strains in primiparous and multiparous cows in six herds with a high prevalence of Staph. aureus intramammary infections.

The proportion of different strains of Staphylococcus aureus was tested in four groups of lactating dairy cows in six herds with a high overall prevalence of Staph. aureus using random amplified polymorphic DNA PCR. Group 1 included primiparous cows in early lactation (<50 days in milk, DIM). Group 2 consisted of primiparous cows in late lactation (>250 days in milk). Groups 3 and 4 were multiparous cows in the respective stages of lactation. Eight cows from each group on each farm were tested. Overall quarter prevalence of Staph. aureus ranged from 23.4 to 32.0% in the herds. Of the 130 isolates included in the analysis 86.9% were high prevalence strains (more than three isolates per herd), while 13.1% were strains that were only identified in one or two samples. Low prevalence strains were found in all six herds. The proportion of low prevalence strains was higher in multiparous than in primiparous cows (odds ratio, OR 4.4, 1.2-16.6). It is concluded that low prevalence Staph. aureus strains are common even in herds with a high prevalence of Staph. aureus and that their frequency is lower in primiparous cows than in older cows.

Concentration of airborne endotoxins and airborne bacteria in Chinese rabbit houses.

Concentration of airborne endotoxins, airborne aerobic bacteria and airborne aerobic gram-negative bacteria were measured in 3 rabbit houses. Further, the species composition of the airborne gram-negative bacterial flora was investigated. The total amount of airborne endotoxin ranged from 22 to 774 EU/m3 (Endotoxin Units/m3). The number of total airborne aerobic bacteria varied between 780 and 20100 CFU/m3, the number of airborne aerobic gram-negative bacteria between 39 and 1030 CFU/m3. Most gram-negative bacterial isolates belonged to the family Enterobacteriaceae with E. coli as primary species. In two rabbit houses also airborne Pasteurella multocida spp. multocida, the most common respiratory pathogen of rabbits, was isolated.

[Relationship between the concentration of different bioaerosol components and the general hygienic condition in two pig fattening houses]. / Beziehungen zwischen der Konzentration an verschiedenen Bioaerosolbestandteilen und dem allgemeinen Hygienezustand in zwei Schweinemastställen.

In the study presented here the relationship between the hygienic condition and the concentration of different air contaminants in two pig fattening houses was investigated. Deficiencies in routine cleaning, which were characterized by an increased soiling of animals and stable surfaces with faeces, led to increased concentrations of airborne dust, airborne endotoxins as well as increased numbers of total airborne bacteria and airborne gram-negative bacteria. However these deficiencies were not reflected by the concentration of airborne Clostridium perfringens which were earlier postulated as an indicator of faecal pollution in the air of cattle barns. Furthermore the results of this study were used to discuss advantages and disadvantages of impingement and impaction for the sampling of airborne microorganisms in animal houses.

[Airborne microorganisms in animal stables: stability of endotoxins in the environment]. / Untersuchungen zum Luftkeimhaushalt in Tierställen: Stabilität von Endotoxinen in der Umwelt.

The stability of endotoxins was investigated in potential sources (feed-stuff, litter, water, excrements, surface dust) of that air contaminant and in the airborne state. No changes in the endotoxic activity were found in materials with high dry matter (straw, hay, dried faeces) during 84 days. In manure samples stages of increasing and decreasing endotoxic activity were observed. In water a continuous decline of the endotoxic activity was found. However this process was characterised by half-life periods on a weekly scale. Bacterial degradation seems to be responsible for that loss of endotoxic activity.

Influence of Oligolysis on the development of Musca domestica in manure.

The effect of electrochemical treatment of liquid manure (oligolysis) on the development of Musca domestica was studied under laboratory conditions. In electrochemical treated manure clearly fewer flies, pupae and larvae were found compared to untreated manure which was primarily the result of destruction of the surface layer on the treated manure. Furthermore our results suggest that the development of larvae and pupae is inhibited during the electrochemical treatment of manure.