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101.
Meat tins denoted as pork in natural juice, beef with bacon, luncheon meat and liver paté, all produced in a food-processing plant, were stored under definite conditions (temperature 21 degrees C, relative humidity 73%) for three years. Before the long-term storage and then in half-year intervals, the contents of the residues of chlorinated pesticides, including HCB (hexachlorobenzene), gamma-HCH (gamma isomer of hexachlorocyclohexane) and pp'DDE (1,1-dichloro-2,2-bis/p-chlorofenyl/-ethylene), were determined in the above-mentioned final products by the method of gas chromatography. As suggested by the records of the changes in the pesticide residue contents in the meat tins during their long-term storage, the average contents of all chlorinated carbohydrates gradually decrease with the length of storage and the "reduction" of residues varies with the kind of final product and with the pesticides. In HCB the reduction ranged from 18.4 to 34.4%, in gamma-HCH from 36.2 to 80.4% and in pp'DDE from 23.9 to 48.9%. 相似文献
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A total of 295 birds belonging to 19 species of 7 families of wild Passeriformes were examined by haemagglutination-inhibition test. The birds were caught for an international research program "Balt" at the time of autumn migration (August-September 1984). Their blood sera were examined for antibodies against 6 arbovirus antigens of the genera Alphavirus (Sindbis-SIN) and Flavivirus (tick-borne encephalitis-TBE, West Nile-WN) and family Bunyaviridae (Tahyna-TAH, Calovo-CVO and Bhanja-BHA). Antibodies against all studied viruses were detected at different frequencies: SIN 6.4%, TBE 7.1%, WN 9.7%, TAH 16.3%, CVO 12.1%, and BHA 1.0%. 相似文献
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S. Nagarajan D. Narahari I. Alfred Jayaprasad D. Thyagarajan 《British poultry science》1991,32(2):243-248
1. Japanese quail hens were housed from 6 to 26 weeks of age in cages providing areas of 150, 180, 210 and 240 cm2/bird.
2. Body weight gain, age at 50% egg production, mortality, hen‐day egg production and food conversion values showed significant improvement with proportionate increase in cage space per layer.
3. Egg weight gradually increased with age but shell thickness was influenced neither by age of the hen nor by stocking density.
4. Yolk index and colour were superior in the lowest stocking density (more cage space) group; other egg quality traits and egg weight were not influenced by stocking density.
5. The albumen index, internal quality unit, yolk index and yolk colour values increased with age. 相似文献