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Biomedical subjects

F D Kirby

Publications and source records attributed to F D Kirby.

13 recordsLinked to original sources
PubMed2003

Prevalence of faecal excretion of verocytotoxigenic Escherichia coli O157 in cattle in England and Wales.

During the decade to 1999, the incidence of human infections with the zoonotic pathogen verocytotoxin-producing Escherichia coli O157 (VTEC O157) increased in England and Wales. This paper describes the results of a survey of 75 farms to determine the prevalence of faecal excretion of VTEC O157 by cattle, its primary reservoir host, in England and Wales. Faecal samples were collected from 4663 cattle between June and December 1999. The prevalence of excretion by individual cattle was 4.2 per cent (95 per cent confidence interval [CI] 2.0 to 6.4) and 10.3 per cent (95 per cent CI 5.8 to 14.8) among animals in infected herds. The within-herd prevalence on positive farms ranged from 1.1 to 51.4 per cent. At least one positive animal was identified on 29 (38.7 per cent; 95 per cent CI 28.1 to 50.4) of the farms, including dairy, suckler and fattening herds. The prevalence of excretion was least in the calves under two months of age, peaked in the calves aged between two and six months and declined thereafter. The phage types identified most widely were 4, 34 and 2, which were each found on six of the 29 positive farms.

Animals↗
PubMed1992

A prolonged outbreak of ornithosis in duck processors.

In 1985 an outbreak of ornithosis affected 13 of 80 (16%) workers in a duck-processing plant. New employees were three times more likely to become cases than established employees. The highest attack rate was in those on the production line. Following the outbreak, an occupational health scheme was set up to monitor the health of new recruits to the company. Serological evidence of recent infection was demonstrated in 18 of 37 (49%) new employees tested in the first 3 months of employment. Five (14%) also had clinical evidence of ornithosis. Veterinary investigation of the ducks demonstrated a high proportion with asymptomatic chlamydial infection. It is suggested that ornithosis may be more common in duck processors than is currently supposed. Strategies to reduce occupational risks are discussed.

Abattoirs↗
PubMed1979

Anomalous development of the spinal cord in a calf.

A full term Friesian bull calf was born unable to stand. The dam had no signs of illness during pregnancy. In the thoracic spinal cord there was anomalous development of the central canal and a dorsally placed fusiform and longitudinal dilatation. Mild inflammatory lesions were seen in some body organs and central nervous system where they were suggestive of viral infection. Several skeletal muscles had an extended range of muscle cell cross sectional areas and some cells had numerous internal nuclei.

Animals↗
PubMed1978

A serological survey on the prevalence of infectious bovine rhinotracheitis in Buckinghamshire, Berkshire and Oxfordshire.

Of the 2368 cattle sera from herds in Buckinghamshire, Berkshire and Oxfordshire examined for infectious bovine rhinotracheitis antibody by an indirect haemagglutination test, 162 (6.8 per cent) proved positive. Positive titres were more prevalent in older cows and they tended to show higher titres. There was little evidence of infection in the bulls tested. The percentage of positive animals in Berkshire and Oxfordshire was 4.7 compared with 10.5 in Buckinghamshire. The infection was not known to be associated with any clinical disease.

Animals↗
PubMed1972

Modification of arithmetic response rate and attending behavior in a seventh-grade student.

An adjusting fixed-ratio schedule of praise and immediate correctness feedback produced increases in a seventh-grade student's arithemic response rate. Percentage of time spent in attending behavior also increased collaterally. Removal of the treatment led to decreases in both arithmetic response rate and collateral attending behavior. Reinstatements of the procedure again produced increases in both types of behavior. It was suggested that the present procedure of directly modifying arithmetic response rate requires less time and effort than working indirectly through modifying attending behavior.

Journal Article↗
PubMed1970

Modification of preschool isolate behavior: a case study.

A 5-yr-old preschool boy with a low rate of interaction with his nursery school classmates was induced to pass out candy as a tactic to increase his rate of interaction with them. Interaction with classmates increased markedly during the periods he passed out choices of candy. These changes may have been due to increases in both his rate of initiating activities with his classmates and to increases in his classmates' rate of initiating activities with him. A total time of less than 1 hr was required of the teacher during the experiment.

Journal Article↗