Dr. Murai Éva szerk.: Parasitologia Hungarica 22. (Budapest, 1989)

Each sample Included all the material from a 20x20 cm floor surface. Samples were weighed on letter-scales. Their mean weight was 160 g.in the calf house, 219 g in cow barn A, 210 g in cow barn B and 258 g in cow barn C. Each sample was put into a glass rearing pot, numbered and its site was marked in a sketch map. Air temperature at a height of 2 m was recorded synchronously. (The cows were not present in the barns during sampling.) Floor temperature was also measured at the sampling sites (one measurement per barn and breeding site type, see Tables 1 and 2). Sampling was repeated on the 14th of July and 15th of August. Altogether 47 samples were taken in the calf house and 13 each in the cow barns. •bbbba a a a a a 0 • <-• 0 dddd a: stalls; b: dung conduit; c: crib; d: feeding way Fig. 2. Groundplan of the cow barns Measurements of cow barns (in m): Inside breadth 12.00 Length of stalls 1.55 Inside length 63.00 Breadth of dung conduit 0.80 Breadth of stalls 1.20 Breadth of crib 0.80 Rearing of flies Five- eight- and one-litre jars were used as rearing pots. Samples were placed into them without changing their moisture content, and covered with a 1-2 cm thick sawdust layer and a blotting paper disk. This method made it easier to take out the Imagos later. The rearing pots were closed with linen covers and kept at a temperature of 20°C 1 1°C in darkness. The developed imagos were collected three times during an 11-week incubation. The imagos (6281 specimens) were identified according to MIHÁLYI's works (1972, 1975), etc

. Diversity index ofthe fly communities found on each sampling day was calculated by Shannon-Wiener's formula (SOUTHWOOD 1978): s H = - p, • l

°e p, s i=i 1 1