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THE EFFECT PELLETED FEED ON THE NUMBER OF MICRO-ORGANISMS IN THE AIR OF PIG FATTENING HOUSES
Vlatko Rupić
; Fakultet poljoprivrednih znanosti, Institut za stočarstvo i mljekarstvo, Zagreb, Republika Hrvatska
Ivo Jurić
; Fakultet poljoprivrednih znanosti, Institut za stočarstvo i mljekarstvo, Zagreb, Republika Hrvatska
Marija Đikić
; Fakultet poljoprivrednih znanosti, Institut za stočarstvo i mljekarstvo, Zagreb, Republika Hrvatska
Romano Božac
; Fakultet poljoprivrednih znanosti, Institut za stočarstvo i mljekarstvo, Zagreb, Republika Hrvatska
Sažetak
The aim of the investigation was to establish the number of microorganisms in the air of pig fattening houses of the traditional type where the animals are fed with peleted feed or meal. Also investigated were the temperature, humidity and speed of air flow both within the fattening houses and outside them at a distance of 20 - 30 metres. The micro-organisms in the air were measured by means of the sedimentation method on Torlak peptonic meat agar.
After the eposure of the Petri dishes with the agar in the biozone of the fattening houses and 30 cm below the ceiling, the agar was left to incubate at 37 "C for 48 hours. The resulting colonies of microorganisms were then counted and calculated per minute and square metre of floor. In the air below the ceiling of the fattening houses in which the animals were fed with pelleted feed the average number of micro-organisms was found to be 102,815, and in the biozone 99,121. The number of micro-organisms in the air below, the ceiling of the fattening houses with pelleted feed was the highest at midday (16,283) and the lowest in the morning (98,294). In the biozone of the pigs fed with pelleted feed the highest number of micro-organisms was established at midday (100,167), and the lowest in the evening (96,584). No significant differences in the numbers of micro-organisms were found between the measurements
below, in the biozone of the fattening houses with pelleted feed (P>0,05).
The average number of micro-organisms in the air below the ceiling of the fattening houses where the animals were fed with meal was found to be 134,257, and in the biozone of the fattening animals 142,376 per minute and square metre of floor. In the air below the
ceiling in the fattening houses with meal the number of micro organisms was found to be increasing in the course of the day to become significantly higher in the evening in comparison with the morning and midday. In the biozone of the pigs fed with meal the lowest number of microorganisms was established in the morning and it was significantly lower than that found at midday or in the evening. In the fattening houses with meal the number of micro-organisms in the biozone was at midday significantly higher than that of the microorganisms found in the air below the ceiling. The number of microorganisms in the air of the fattening houses with meal (morning, midday, evening) was significantly higher in the air below the ceiling and in the biozone than the number of micro-organisms found in the fattening houses with pelleted feed.
The temeperature, humidity and speed of air flow in all fattening houses were not within the norms for fattening pigs being greatly influenced by external climatic conditions.
Ključne riječi
Hrčak ID:
162049
URI
Datum izdavanja:
22.9.1990.
Posjeta: 975 *