Isolation of Mycobacterium Paratuberculosis from Sheep and Cattle in Iceland

Isolation of Mycobacterium paratuberculosis from sheep and cattle in Iceland. Acta vet. scand. 1979, 20, 191–199. — Culture experiments concerning the Icelandic variant of Mycobacterium paratuberculosis are described. Various decontaminating agents and culture media were employed and the colonial morphology of freshly isolated strains on different media described. The growth rate and culture requirements are compared with those of the Norwegian goat-pathogenic variant of M. paratuberculosis. For primary isolation modified Herrold’s medium gave the best results. However, on all the various culture media used, the growth of the Icelandic variant was much more sporadic than that of the Norwegian goatpathogenic variant. It is concluded that bacteriological culture is not useful for the diagnosis of Johne’s disease caused by the Icelandic variant of M. paratuberculosis.     

Salmonella Contamination of Sheep and Mutton Carcasses Related to Pre-slaughter Holding Conditions

S ummary . When sheep were held in abattoir pens, the fleece became contaminated with salmonellae within 1 day even when there was less than 1 salmonella/g of soil. Salmonellae were first shed in the faeces after 2–3 days. Both the percentage of infected sheep and the number of salmonellae/g of faeces subsequently increased rapidly. Contamination of fleece and carcasses increased with time and with the degree to which the pens were contaminated. The fleece appeared to be a significant source of salmonella contamination of the carcass.     

Gendered genetics in Iceland

The integration of Iceland's phenotype and genotype, by bringing together the medical records, genealogies and genetic data by the commercial firm deCODE has been one of the most studied and controversial cases of the new pharmacogenomics. This paper explores the differences between the concerns and conceptualizations of women and men in debating this biomedical innovation.     

Defining the supernatural in Iceland

This article does not have an abstract     

Age at menarche in Iceland

The purpose of this study was to elucidate the mean age at menarche in Icelandic girls and compare it with results from other Scandinavian populations as well as in other ethnic groups. The study was performed during the school year 1972-1973 on a cross-sectional sample of 682 girls (aged 8.5 to over 17 years), constituting 9.5% of the girls from the third to eleventh forms in all the primary and secondary schools of Reykjavik. The mean age at menarche in Iceland, elicited by the status quo method, proved to be 13.06 +/- 0.10 years (S.D. 1.17 years). According to the information given by the girls (recall method), the earliest time of menstruation was 9.83 years and the latest 15.17 years, at which age all but one of the girls were menstruating.     

Bacillus stearothermophilus in Soils of Iceland

Bacillus stearothermophilus was found in Icelandic soils. Of the 33 strains studied, only four grew at 25 C. Temperatures as high as 27 C in bare soil at a depth of 1 to 1.5 cm were measured at the collection site. However, to demonstrate growth the cultures had to be incubated for 3 weeks, and soil temperatures remained at 27 C only for shorter periods of time.     

Toxoplasmosis in Sheep

The presence of Toxoplasma gondii in the diaphragm was correlated with the dye test titres in 174 sheep. In 94 of these the presence of the parasite was also correlated with the haemoglobin (Hb) type. T. gondii was recovered from 3 % of the sheep with titres < 1/16, compared with 30 % of those with titres 1/16 and 70 % of those with titres ≥ 1/32. The results indicate that the distinction between serologically positive and negative individuals at a final serum dilution of 1/16 is justified. Some evidence was found that the parasite is easier to recover from dye test positive mature sheep than from dye test positive lambs. Of the 174 sheep, 143 were examined at random among 186 sheep culled or cast for age during a 4-year period from 1 flock in which the prevalence of Toxoplasma antibodies was representative for flocks in the southern Norway, and T. gondii was recovered from 53 (37 %) of these. It was concluded that 10—15 % of the lamb carcases and 25—37 % of the carcases from mature sheep in this country have T. gondii in their muscles detectable by the peptic digestion technique. A possible genetical influence on the infection was indicated by the higher frequency of recoveries of T. gondii from sheep with Hb type B than from sheep with the Hb types A or AB, but the number of individuals with Hb type B was too small to demonstrate statistically significant differences. The epidemiological importance of infected sheep carcases is discussed.     

Listeriosis in Sheep

Listeriosis in sheep. Listeria monocytogenes excretion and immunological state in healthy sheep. Acta vet. scand. 1979, 20, 168–179. — The excretion of Listeria monocytogenes (Lm) in the faeces and milk, and humoral and cell mediated immunity against Lm, were examined in a sheep flock where no cases of listeriosis had occurred during the last 3 years. The investigation was carried out during the indoor season. During the first part of the season 2 of the 10 pregnant, 8 months old lambs excreted Lm in the faeces, but none of the 106 ewes, 2–10 years old. At lambing the organism was isolated from the faeces of 6 of the 10 1 year old lambs and from 64% of the ewes, and from the milk of 1 of the lambs and 41% of the ewes. Nearly all the isolates (98.5%) belonged to serotype 1. Antibody titres against Lm were found in sera and whey by an indirect haemagglutination method. The titres were higher for the ewes than for the hoggs and seemed to be influenced by the number of foetuses the animals carried. Cell mediated immunity was determined by a skin test where delayed hypersensitivity against an antigen prepared from Lm, was measured. Animals fed grass silage had a stronger reaction than animals fed hay, and a stronger reaction was found in animals with ≥ 3 foetuses than in the remainder. The investigation indicates that even in a healthy sheep flock all the animals may be exposed to Lm, and the majority may be latent carriers and excrete this organism in the faeces and milk during periods of stress.     

Toxoplasmosis in Sheep

The epidemiology of toxoplasmosis in sheep was studied during a period of 31/2 to 6 years in 4 flocks in which abortions from the infection previously had occurred. The epidemiological pattern indicated that a heavy contamination of the environment may persist for about 2 years. Even in flocks with an apparently normal reproductive performance, toxoplasmosis may cause barrenness, abortion or delivery of dead lambs in 1–2 % of the breeding ewes. The prevalence of infected sheep increased with the age. The incidence of infection was significantly lower in 6–12 months old lambs than in mature ewes. The incidence of infection was higher on lowland pastures than on mountain pastures in not populated areas. On lowland pastures the incidence of infection was lower during the summer than during the winter. kw|Keywords|k]toxoplasma infection; k]epidemiology; k]sheep {fn1|This work was supported by grants from the Norwegian Research Council for Science and for the Humanities.}     

Listeriosis in Sheep

Two hundred and ninety-one grass silage samples from 113 farms with recent outbreaks of listeriosis were examined for the presence of Listeria monocytogenes (Lm). The frequency of Lm isolations increased with increasing pH. Lm was isolated from 22 % of the samples with pH < 4, from 37 % with pH 4–5 and from 56 % with pH > 5. Formic acid had been used as additive. A similar investigation was carried out on 32 samples from a farm with no outbreak of listeriosis during the investigation period. Lm was isolated from 9 samples.