The in vitro activity of pefloxacin, norfloxacin, ofloxacin and ciprofloxacin against 86 strains of mycobacteria was evaluated by broth dilution. While Mycobacterium avium, Mycobacterium scrofulaceum and Mycobacterium chelonae were resistant to all four antibacterials, the susceptibility of the other species, Mycobacterium tuberculosis, Mycobacterium kansasii, Mycobacterium xenopi and Mycobacterium fortuitum, depended on the antibiotic. Ofloxacin and ciprofloxacin (MIC90: 0.5 - 2 mg/l) were more active than pefloxacin and norfloxacin (MIC90: 2 - 16 mg/l).

No abstract

No abstract

Groups E and F had free access to food from 2 i to 25 weeks of age. Group E was then restricted by allowing access to food for 2 X 2 hour periods (8-10 h and y -y h). From z! to 3! weeks of age, group h received food for 4 consecutive hours (8 to r2 a.m.) followed by 6 hours of feeding (8 a.m. to 2 p.m.) from 37 to 66 weeks of age.While groups B and D receiving measured amounts of feed showed a 9 .i p. ioo restriction in practice, group C ate 11 . 1 p. ioo less than the controls. Limiting access time resulted in a similar level of restriction, group E consuming I 1 . 4 p. 100 less, while group F was subjected to the severest restriction at r 3 .8 p. 100 .In all restricted treatments, the food efficiency was improved and the cost of production of i kg of egg decreased. The best result in economic terms, was achieved by treatment E.The study suggests that it is better to distribute the food at 3 p.m. instead of 8 a.m. and it is not advisable to increase the level of restriction towards the end of the laying period.Access to food for 4 consecutive hours leads to an insufficient food intake and poor production. It is necessary to increase the time of access to 6 hours or split it to two hours in the morning and two in the afternoon.