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Occupational exposure to airborne microorganisms, endotoxins and beta-glucans in poultry houses at different stages of the production cycle

100%

Lawniczek-Walczyk A., Gorny R. L., Golofit-Szymczak M., Niesler A., Wlazlo A.

Annals of Agricultural and Environmental Medicine

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2013

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tom 20

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nr 2

The aim of the presented study was to assess the exposure of poultry workers to airborne microorganisms, endotoxins and β-glucans during different stages of the chicken production cycle in 3 commercially-operated poultry houses. Personal and stationary sampling was carried out to assess exposure to both viable and total microbial aerosols. The stationary measurements of PM10 were performed to establish the level of endotoxins and β-glucans. The concentrations of bacterial and fungal aerosols ranged from 2.5×102 CFU/m3 – 2.9×106 CFU/m3, and from 1.8×102 CFU/m3 – 1.8×105 CFU/m3, respectively. The number of culturable microorganisms was significantly lower than their total counts, constituting from 0.0004% – 6.4% of the total microbial flora. The level of PM10 in poultry facilities did not exceed 4.5 mg/m3. After the flock entered the clean house, the level of endotoxins and β-glucans increased from below detection limit to 8,364 ng/m3 and from 0.8 ng/m3 to 6,886 ng/m3, respectively. The presented study shows that professional activities in poultry farms are associated with constant exposure to bioaerosol, which may pose a health hazard to workers. It was found that workers’ exposure to airborne microorganisms increased with consecutive stages of the chicken production cycle.

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The life-history traits and seedling recruitment of Dianthus superbus L. in different stages of meadow overgrowing

100%

Kostrakiewicz-Gieralt K.

Acta Agrobotanica

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2014

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tom 67

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nr 2

A study of the life-history traits and seedling recruitment in small and isolated populations of a rare clonal species, Dianthus superbus L., was carried out in the years 2011–2012 in Kraków-Kostrze (Southern Poland). Observations were conducted in unmanaged Molinietum caeruleae meadows situated along the successional gradient. The patch representing the initial stage of succession (P1) was dominated by small species creating delicate erect or procumbent stems, the patch representing the temporary stage of succession (P2) was prevailed by large-tussock grasses and tall-growing macroforbs, while the patch representing the terminal stage of succession (P3) was partly overgrown by bushes and trees. The number of generative shoots, flowers, fruits and seeds of Dianthus superbus L. diminished gradually from P3 via P2 to P1. The increase in abundance of generative shoots and flower number in the vicinity of tall plants contributes to increased visibility of inflorescences and may enhance the chances for nocturnal pollinator visits. A significant production of fruits and seeds in competitive neighborhood may augment the chances for successful dispersal and colonization of new, perhaps more favorable habitats. The recruitment of seedlings occurred only in artificially created gaps in plant canopy and litter. The appearance of seedlings and their survivorship were better in P1 than in P2 and P3. Such a phenomenon might be due to the locally rising water level and the diminishing amount of light reaching to the soil area along the successional gradient. Concluding, it should be asserted that a low production of generative shoots, flowers, fruits and seeds by the population of Dianthus superbus L. established in the patch dominated by small meadow species is compensated by the highest seedling recruitment and their survival. On the other hand, a substantial production of generative structures is not sufficient to ensure the persistence of populations in meadows in advanced stages of secondary succession.

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Micromorphology of nectaries of Rhododendron catawbiense Michx. at different flower development stages

80%

Weryszko-Chmielewska E., Chwil M., Michonska M.

Acta Agrobotanica

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2007

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tom 60

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nr 2

The analysis of the structure of floral nectaries of Rhododendron catawbiense Michx. was performed using stereoscopic, light and scanning electron microscopy. Nectaries were sampled at different development stages: closed bud, budburst and full bloom. The nectary gland exhibits clear ribbings corresponding to five small ribs of the ovary. In the top part of the gland, unicellular and multicellular non-glandular trichomes occur in great density. The upper surface of the nectary differs from its lateral surface by a stronger degree of cuticle development. Stomata are evenly distributed on the upper surface and in the higher regions of the lateral wall. The cuticle forms clear striae on the surface of stomatal cells. Stomata at different development stages were observed, as well as the beginning of nectar secretion which takes places already in the closed bud.

Ograniczanie wyników

2 Acta Agrobotanica

1 Annals of Agricultural and Environmental Medicine

1 Chwil M.

1 Golofit-Szymczak M.

1 Gorny R. L.

1 Kostrakiewicz-Gieralt K.

1 Lawniczek-Walczyk A.

1 Michonska M.

1 Niesler A.

1 Weryszko-Chmielewska E.

1 Wlazlo A.

1 2014

1 2013

1 2007

Occupational exposure to airborne microorganisms, endotoxins and beta-glucans in poultry houses at different stages of the production cycle

The life-history traits and seedling recruitment of Dianthus superbus L. in different stages of meadow overgrowing

Micromorphology of nectaries of Rhododendron catawbiense Michx. at different flower development stages