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S C Hathaway

Publications and source records attributed to S C Hathaway.

At least 55 records · Page 3Linked to original sources
PubMed1983

Isolation of Leptospira interrogans serovar hardjo from a viable premature calf.

A severe outbreak of agalactia in a dairy herd of 80 cows was followed by six premature calvings and an abortion. Serological and bacteriological studies identified Leptospira hardjo as the probable cause. A leptospire isolated from the kidney of a premature calf killed seven weeks post partum was identified as hardjo and it is probable that this infection was acquired in utero. The maintenance of such an infection for a considerable period after birth has not been previously described and may play a role in the transmission of hardjo to susceptible in-contact animals.

Abortion, Veterinary↗
PubMed1983

Identification of a reservoir of leptospira interrogans serovar muenchen in voles (Microtus agrestis and Clethrionomys glareolus) in England.

Infection with leptospires of the Australis serogroup is widespread in voles in Southern England and the serovar identification of five randomly-selected isolates was determined by cross agglutination absorption. Two isolates from short-tailed voles (Microtus agrestis) and three isolates from bank voles (Clethrionomys glareolus) were all identified as serovar muenchen. The only previous isolation of this serovar is that from a human in Germany.

Agglutination Tests↗
PubMed1983

Serovar identification of leptospires of the Australis serogroup isolated from free-living and domestic species in the United Kingdom.

Eighteen isolates from the Australis serogroup from free-living and domestic animals were identified using the cross agglutination absorption test. Serovar muenchen was found only in England and Wales in wood mice, short tailed and bank voles, a grey squirrel and a pig. Serovar bratislava was found in hedgehogs in England, Wales and Northern Ireland and also in a brown rat from Northern Ireland. Serovar bratislava was isolated from sheep in both England and Northern Ireland and from horses in Northern Ireland. The distribution of these serovars in relation to possible maintenance hosts is discussed.

Agglutination Tests↗
PubMed1983

Leptospirosis and the maintenance host: a laboratory mouse model.

A laboratory mouse model was used to investigate the criteria that have been suggested as differentiating between a maintenance host and an accidental host for a particular leptospiral serovar. The comparative studies were conducted with serovars ballum, pomona, balcanica and hardjo. The relative pathological response, ratio of serological to bacteriological prevalence, level of serological response, age-susceptibility to infection and demonstration of artificial intraspecies transmission were found to be inadequate criteria with which to differentiate maintenance and accidental hosts for a particular serovar. The demonstration of natural intraspecies transmission was considered to be the definitive criterion for differentiating such hosts. In the light of the results obtained from the laboratory mouse model and the results obtained from field studies, a maintenance host may be defined as an animal which is capable of acting as a natural source of leptospiral infection for its own species. A maintenance population may be defined as a population of a species of animal which acts as a continuous reservoir of a serovar in a specific ecosystem.

Age Factors↗
PubMed1982

Isolation of Leptospira interrogans serovar muenchen from a sow with a history of abortion.

The isolation of Leptospira interrogans serovar muenchen from a sow which aborted in the first third of pregnancy is described. Isolation was achieved only in media containing a rabbit serum additive and identification was determined by cross-agglutination absorption. A high degree of cross-reactivity was found with reference antisera of the Australis serogroup. Serovar muenchen has not previously been reported in animals and may be responsible for a proportion of the titres to antigens of the Australis serogroup that have recently been reported in pigs in England.

Abortion, Veterinary↗
PubMed1982

Serological survey of leptospiral antibodies in sheep from England and Wales.

A total of 3722 sera was obtained from 188 flocks widely distributed throughout England and Wales; three sera were randomly selected from each flock and tested in the microscopic agglutination test for leptospiral antibodies. Infection with leptospires of the Hebdomadis serogroup was found to the widespread and it is probable that the infecting serovar is hardjo. The prevalence of hardjo titres in the random survey was 6.4 per cent and within-herd prevalences ranged up to 94.4 per cent. Titres to autumnalis antigen were found in 7.3 per cent of sera and evidence is presented that suggests a proportion of these titres are cross-reactions with agglutinins stimulated by infection with leptospires from other serogroups. Titres to bratislava antigen (Australis serogroup) were found in 3.4 per cent of sera. Within-herd prevalences of autumnalis and bratislava titres did not range above 16.7 per cent and 26.3 per cent respectively.

Animals↗
PubMed1982

Failure to demonstrate the maintenance of leptospires by house mice (Mus musculus) in the south east of England.

A total of 272 house mice (Mus musculus) were trapped in farm buildings at four widely separated locations of south east England and examined for serological and bacteriological evidence of leptospiral infection. Only two low titres to autumnalis antigen (1:20 and 1:40) were recorded and all mice were bacteriologically negative. The absence of leptospiral infection in the house mouse in south east England is an interesting ecological finding, as this species is a maintenance host for ballum in many countries and also a common carrier of several other serovars. The source of ballum infections in domestic stock in England remains unknown.

Animals↗
PubMed1981

Prevalence and clinical significance of leptospiral antibodies in pigs in England.

The results of leptospiral serology conducted on porcine sera at the Central Veterinary Laboratory, Weybridge from 1971 to 1978 were collated and analysed. Sera were available from diagnostic submissions (1622) and from pigs intended fro export (5031). A random sample of 792 sera from 34 herds was also examined. The overall prevalence of infection was low. Copenhageni titres were present in 7.9 per cent of diagnostic submissions and a statistical association with jaundice was shown in piglets and adults. The introduction of Australis serogroup antigens in 1978 revealed the serological prevalences to lora and bratislava to be in excess of 20 per cent. However the causative serotype has yet to be identified. Leptospiral infection was not a significant cause of abortion in pigs. The pattern of leptospiral infection in pigs in England is considerably different from that occurring in other countries and it is considered that free-living maintenance host populations constitute the primary sources of infection.

Abortion, Veterinary↗
PubMed1981

Ecological aspects of the epidemiology of infection with leptospires of the Ballum serogroup in the black rat (Rattus rattus) and the brown rat (Rattus norvegicus) in New Zealand.

Epidemiological aspects of infection with leptospires of the Ballum serogroup in black rats (Rattus rattus) and brown rats (Rattus norvegicus) are described. Rats inhabiting a variety of habitats were investigated and isolates identifed as belonging to the Ballum serogroup were obtained from 21 of 61 black rats (34%) and 63 of 243 brown rats (26%). The high level of endemic ballum serogroup infection in these species reported here has not been described in other countries. A statistical relationship was shown between the prevalence of infection in brown rat populations and population density but this was not evident for black rats. Epidemiological data indicates that the black rat is a maintenance host for leptospires of the Ballum serogroup in New Zealand. The brown rat does not appear to be an efficient maintenance host for these leptospires, however endemic infection can be maintained in high-density populations inhabiting synanthropic foci. An hypothesis of 'competitive exclusion' (preferential maintenance of a particular serovar by a host species) is introduced with regard to leptospiral infection in brown rats. It is concluded that the establishment and maintenance of an endemic focus of leptospirosis is dependant on: introduction of a particular serovar; a suitable host; and a suitable host habitat. Within a maintenance population direct transmission appears to be more important than indirect transmission via the environment.

Animals↗
PubMed1981

Leptospirosis in free-living species in New Zealand.

A total of 1296 free-living mammals and birds of 12 species was examined for serologic and bacteriologic evidence of leptospiral infection. Endemic infection with serovar ballum was found in several introduced species of mammals. Endemic ballum infection is not recognized in the same species in Great Britain, their country of origin. Possums (Trichosurus vulpecula) were found to have a high prevalence of infection with balcanica, a serovar that has been isolated from possums in Australia and from cattle, pigs and humans in Eastern Europe. Free-living lagomorphs and deer were both serologically and bacteriologically negative. Waterfowl were bacteriologically negative, and only one serological titre was found.

Animal Population Groups↗