Occurrence and distribution of antibiotic resistant E. coli strains in faeces from young pigs and calves in Denmark]

A comparative study of investigations from 1970 (before the prohibition against therapeutically used antibiotics as food additives for growth promotion) and from 1978 respectively proves that the prevalence of young pigs and calves with resistant E. coli has increased significantly from 61% to 92% and from 69% to 86% (tables I and II). Figures 1 and 2 show the prevalence of young pigs and calves with antibiotic resistant E. coli with resistance determinants towards sulfonamides, tetracycline, streptomycin, ampicillin, chloramphenicol, neomycin and furazolidone. This shows that the prevalence of young pigs with resistance determinants towards sulfonamides, tetracycline, streptomycin, ampicillin, and chloramphenicol has increased significantly from 1970 to 1978. The same facts apply to the calves. However, the increase in tetracycline resistance is not significant. Neomycin resistant E. coli for both young pigs and calves were only found in 1978. Figure 3 shows the distribution of the number of resistance determinants per young pig and calf with resistant E. coli. The figure shows the significant tendency that the pigs and calves investigated contain resistant E. coli with more resistance determinants in 1978 than in 1970. The distribution of R-factors among resistant E. coli seems to be reduced at first sight but a closer examination establishes that this only goes for R-factor mediated sulfonamide resistance (the experimental conditions may account for this). R-factor mediated streptomycin resistance has increased while R-factor mediated tetracycline resistance was at the same level. On the basis of literature the causes and risks of an increased distribution of antibiotic resistant E. coli are discussed.     

Bacteria profiles in four coastal areas of East Zealand--coliform bacteria, E. coli and vibriolike organisms (VLO) (author's transl)]

The prevalence of E. coli, coliforms and Vibrio-like-organisms has been studied at four different sites along the east coast of Zealand. High values were registered in sediment taken from the water-line and at a depth of one meter. Generally there exist significant differences between the bacterial counts of water and sediment, and it is obvious that the greatest concentration is in the waterline sediment. The epidemiological and hygienic consequences of these facts are discussed.     

Theileria mutans in Nigeria.

Two strains of bovine Theileria from northern Nigeria were shown to be identical to Theileria mutans in the indirect immunofluorescent antibody test. One of the strains was transmitted by the tick Amblyomma variegatum; large macroschizonts, typical for T mutans, could be demonstrated in infected cattle. It is concluded from these experiments and from the literature that there is reliable evidence so far for the occurrence in Nigeria of only two bovine Tehileria species, T mutans and T velifera.     

Phosphatase activity in avian mycoplasmas.

Fifty-four strains of avian mycoplasma representing 11 species or serotypes were examined for their phosphatase activity using two different methods. Both methods gave similar results. All of four strains of Mycoplasma anatis and six of M meleagridis and the type strain of serotype L were phosphatase positive. The other species gave variable reactions between strains and on different occasions of testing.     

Structure of the sheep epidermis.

The stratum corneum measured on fresh frozen sections was found to be considerably thicker than previously reported. It was uniformly permeated with sebum, which also formed an intact film over the skin surface and it could readily be divided into two zones. The living epidermis was approximately half as thick as the stratum corneum.