PubMed Health⌕ Search

Biomedical subjects

G Gettinby

Publications and source records attributed to G Gettinby.

At least 19 recordsLinked to original sources
PubMed2000

Pathogenesis and diagnosis of infections with Mycobacterium bovis in cattle. Independent Scientific Group on Cattle TB.

In last week's Veterinary Record, members of the Independent Scientific Group on Cattle TB discussed the approach they are adopting in attempting to develop sustainable strategies for controlling bovine tuberculosis in cattle (VR, February 19, pp 207-210). In this second, complementary article, they consider the extent to which efforts to control the disease may be constrained by limitations in current testing procedures.

Animals↗
PubMed2000

Bovine tuberculosis: towards a future control strategy.

The Independent Scientific Group on Cattle TB was appointed by the Government in 1998 to implement and develop the research recommendations of the 1997 Krebs report on bovine tuberculosis in cattle and badgers. In this article, members of the group discuss the approach they are adopting in attempting to ensure that future control strategies are scientifically based. In a second article, to be published in next week's Veterinary Record, the group will consider the extent to which efforts to control the disease in cattle may be constrained by limitations in current testing procedures.

Animals↗
PubMed1999

Demographic characteristics of the equine population of northern Britain.

The size, composition and distribution of the equine population of Scotland and the five northernmost counties in England were estimated through a series of mailed questionnaire surveys of sentinel veterinary practices and horse owners. An estimated 96,622 equine animals were kept by an estimated 26,114 owners. The mean (sd) age of the population was 11.0 (7.5) years (range one month to 37 years). Thoroughbred or thoroughbred-cross animals were the most numerous, constituting 30 per cent (95 per cent confidence interval 27 to 33 per cent) of the total population. The ratio of males:females was 1:1.

Animals↗
PubMed1999

Development of a decision support system for trypanocidal drug control of bovine trypanosomosis in Africa.

During this century livestock production has increased massively through the improved ability to diagnose, treat, control and prevent certain diseases. Despite these advances, disease remains a major constraint to livestock production and welfare throughout the world. In many instances, this is a result of failure to properly apply methods that are already available. TrypsChemo is an expert system that attempts to aid the application of veterinary knowledge to disease management. It has been designed to maximise the effectiveness and cost efficiency of the different trypanocidal drug regimens currently available for prophylaxis and treatment of tsetse-transmitted bovine trypanosomosis in Africa. This paper describes the design of TrypsChemo, the properties of the system, and illustrates how it can be used to support decision making for trypanocidal drug control. The system is currently undergoing a structured evaluation by potential users in Africa.

Africa↗
PubMed1999

Models of temporal variation in questing activity in individuals of Ixodes ricinus (Acari: Ixodidae).

Intensive observations of the questing activity of Ixodes ricinus ticks in the field were made to provide data on the range of durations of periods of continuous questing activity, and of the variation in questing activity between individuals. Continuous periods of questing were observed to extend to a maximum of 28 hours. Substantial variation in questing activity between individuals was observed. Models fitted to the distribution of durations of bouts of questing activity provide insights into the questing ecology of I. ricinus. Results suggest that questing duration may not be solely dependent on the state of hydration of the tick. A function fitted to the frequency distribution of the proportions of active life that individuals spend on questing, provides an empirically-based model that can be used to generate a stochastic expression of variation of questing activity in individuals in a questing population.

Algorithms↗
PubMed1999

The use of dummy data points when fitting bacterial growth curves.

We consider the problem of fitting mathematical models for bacterial growth and decline to experimental data. Using models which represent the phases of the growth and decline cycle in a piecewise manner, we describe how least-squares fitting can lead to potentially misleading parameter estimates. We show how these difficulties can be overcome by extending a data set to include hypothetical observations (dummy data points) which reflect biological beliefs, and the resulting stabilization of parameter estimates is analysed mathematically. The techniques are illustrated using real and simulated data sets.

Anaerobiosis↗
PubMed1998

Studies on host resistance to tick infestations among trypanotolerant Bos indicus cattle breeds in east Africa.

Recent epidemiological studies carried out in East Africa have indicated that some Bos indicus cattle breeds such as the Orma Boran and Maasai Zebu have a degree of trypanotolerance worth exploitation by their introduction into trypanosomosis endemic areas where other cattle breeds cannot survive. However, in most areas of East Africa, trypanosomosis, ticks, and tick-borne diseases occur together. It is therefore important to obtain information on the susceptibility of these breeds to tick infestation and tick-borne diseases. This study was therefore designed to determine the susceptibility of these cattle breeds to tick infestations. They were compared with the Galana Boran (trypanosusceptible) and the Friesian (susceptible to tick infestations, tick-borne diseases, and trypanosomosis). The four breeds of cattle were exposed to natural tick challenge for a period of seven months and whole body weekly tick counts were done on each animal. Significant differences to tick infestations among the four breeds were observed. For both Rhipicephalus appendiculatus and Boophilus decoloratus, susceptibility to infestation increased in the order, Maasai Zebu, Orma Boran, Galana Boran and Friesian. The results generated by this pilot study so far suggest that variation in susceptibility to tick infestations exists among the four breeds. The Orma Boran and Maasai Zebu showed greater resistance to tick-infestations than the Galana Boran and Friesian. This suggests that utilization of these trypanotolerant cattle breeds could be feasible even in the face of tick challenge and should therefore be considered when planning integrated trypanosomosis and tick control strategies.

Africa, Eastern↗
PubMed1998

Application of probability techniques to the objective interpretation of veterinary clinical biochemistry data.

Methods for the interpretation of veterinary clinical biochemistry have not developed as rapidly as biochemical technology. However, the results of clinical biochemistry tests are only of value when they are interpreted appropriately. A retrospective study was undertaken to investigate the equine biochemistry data which had been stored in a veterinary hospital database. By applying percentile analysis and Bayesian probability methods to the clinical biochemistry and corresponding diagnosis data, a novel method for the interpretation of clinical biochemistry data has been developed. The method allows clinicians to determine whether a biochemistry value is abnormal, its degree of abnormality, and the most likely associated diagnoses. The method could be used to investigate a practice-based population and may have significant implications for the interpretation of clinical biochemistry data in veterinary medicine in the future.

Animals↗
PubMed1998

Objective interpretation of bovine clinical biochemistry data: application of Bayes law to a database model.

With the advent of animal-side biochemistry analysers in veterinary practice, the requirement for ready access to reliable means for interpretation of the results is of increasing importance. At the University of Glasgow Veterinary School (GUVS), a large computerised hospital database containing extensive clinical, laboratory, and pathological information has been maintained. A retrospective study was undertaken to investigate plasma biochemistry results and corresponding post mortem diagnosis data from 754 unwell cattle which had presented to GUVS over the study period. Initial analysis of the clinical biochemistry data from this unwell population revealed that the parameters did not follow a normal distribution. This finding suggested that the accepted reference range method for the interpretation of clinical biochemistry data may provide limited information about the unwell animal. By applying a combination of percentile analysis and conditional probability techniques to the hospital data, the development of a means of clinical biochemistry interpretation was developed whereby a clinician could determine whether a value was abnormal, the degree of abnormality, and the most likely associated diseases. For example, a urea value of 30 mmol/l lay within the top 5% of results, and one of the most common diseases associated with this urea value was pyelonephritis. Furthermore, a Bayesian approach allowed the quantification of the relationship between any plasma biochemistry value and disease through the generation of a ratio termed the 'biochemical factor'. Using the same example, given a urea value of 30 mmol/l, pyelonephritis was eight times more likely than before any biochemistry information was known. The results from the study were used to form the basis of a software system which may ultimately be used by the clinical to aid in the recognition, treatment and prevention of disease in the veterinary domain.

Animals↗
PubMed1998

Susceptibility to trypanosomosis of three Bos indicus cattle breeds in areas of differing tsetse fly challenge.

Studies to assess the differences in susceptibility to trypanosomosis among Bos indicus cattle breeds (Maasai Zebu, Orma Boran and Galana Boran) were conducted under conditions of varying tsetse fly challenge at the Nguruman escarpment in south-western Kenya, for a period of 1 year. It was found that under tsetse challenge quantified as high, Maasai Zebu and Orma Boran were less susceptible than Galana Boran to trypanosome infections, as judged by the significantly lower incidence of infection, development of less severe anaemia, fewer requirements for trypanocidal drug treatments, higher growth rates and fewer mortalities. In the area where tsetse challenge was considered low as a result of a tsetse fly control operation using odour-baited traps, only the Maasai Zebu and Orma Boran were compared. No significant differences in the incidence of infection, degree of anaemia or growth rates were observed between the two breeds, but all were significantly different from their counterparts in the high tsetse challenge area. These results suggest that there is variation in resistance to trypanosomosis among Bos indicus cattle breeds that could be exploited as part of the integrated trypanosomosis control programmes in East Africa.

Anemia↗
PubMed1998

Ixodes ricinus strains in Europe.

An analysis of cuticular hydrocarbons (CH) of unfed adult Ixodes ricinus ticks collected throughout Europe showed that there are 10 distinct I. ricinus groups. Studies on the seasonal and annual consistency of CH composition and possible effects of host and environmental factors suggested that CHs may be used as a genuine genetic marker for I. ricinus. Preliminary studies compared the vector competence of ticks from three of the most separated I. ricinus groups and the results suggested that there may be significant differences in tick susceptibility to Borrelia afzelii.

Animals↗
PubMed1998

Lyme borreliosis habitat assessment.

Tick ecologists throughout Europe provided descriptions of Lyme borreliosis habitats according to a standardised format and data for 105 habitats in 16 countries were received. The data showed that high risk situations, as defined by the presence of large numbers of B. burgdorferi sensu lato-infected nymphal I. ricinus, occur in heterogeneous deciduous woodland, usually with a recreational function and with a diverse fauna, usually including deer. Large numbers of ticks occurred in some other habitats, but infection prevalence was usually low. The situation for adult I. ricinus was similar but less clearly defined. Tick infection rates were found to be lower in western Europe than in the east, and the infection rate in I. persulcatus, the most easterly vector species, was markedly higher than in I. ricinus. In the vast majority of habitats the infection rate in adult I. ricinus was greater than in nymphs. Larvae were rarely found to be infected.

Animals↗
PubMed1998

Lyme borreliosis awareness.

A Lyme borreliosis information leaflet has been produced to promote awareness amongst the general public. It was designed to provide a framework for similar material throughout Europe and complements a questionnaire produced to measure awareness of Lyme borreliosis. This questionnaire can be used to determine the impact of educational campaigns using material such as the leaflet. Feasibility studies showed that the questionnaire successfully highlighted predictable differences between sample groups and also that the leaflet performed well in increasing knowledge in low-awareness groups.

Blood Donors↗
PubMed1998

The European Union Concerted Action World Wide Web site for Lyme borreliosis.

This web site (URL http://www.dis.strath.ac.uk/vie/LymeEU/) provides information on Lyme borreliosis for physicians, scientists, health care workers, veterinarians and students. It consists of a review of the spirochaetes, vectors, reservoir hosts, diagnosis, treatment, epidemiology and prevention of the disease, as well as an account of the activities of EUCALB.

Computer Communication Networks↗
PubMed1998

Pharmacodynamics and pharmacokinetics of tolfenamic acid in ruminating calves: evaluation in models of acute inflammation.

Injections of mild irritants intradermally (carrageenan, zymosan and dextran) and intracaveally (carrageenan) in a tissue cage model of inflammation were used in studies of the pharmacodynamics and pharmacokinetics of tolfenamic acid administered intramuscularly in calves. Inhibition of serum thromboxane (TX)B2 and inflammatory exudate prostaglandin (PG)E2 were used as indicators of the magnitude and time course of blockade of cyclo-oxygenase isoforms COX-1 and COX-2, respectively. Single doses of 2, 4 and 8 mgkg-1 tolfenamic acid partially inhibited irritant-induced rises in skin temperature (non-dose dependently) and skin oedema (dose-dependently). These doses also markedly inhibited serum TXB2 synthesis and the duration of inhibition was dose-related. A dose of 2 mgkg-1 tolfenamic acid also attenuated skin temperature rise over carrageenan-injected tissue cages, and markedly inhibited exudate PGE2 synthesis, even though drug penetration into both exudate and tissue cage transudate was limited. Tolfenamic acid pharmacokinetics were characterized by a relatively short tmax (0.94-2.04 h), a high estimated Vdarea (1.79-3.20 Lkg-1), an estimated t1/2 beta of 8.01-13.50 h and Cl beta of 0.142-0.175 Lkg-1h-1. The actions of tolfenamic acid in inhibiting PGE2 synthesis and in attenuating two of the cardinal signs of inflammation (heat and swelling) suggest that a dosage of 2 mgkg-1 administered intramuscularly should be effective clinically as an anti-inflammatory agent.

Animals↗
PubMed1998

The processes influencing the distribution of parasitic nematodes among naturally infected lambs.

The impact of mixed, nematode infection upon a group of animals will depend upon the number of nematodes present, how they are distributed among hosts and whether individuals that are heavily parasitized with one species are more likely to be heavily parasitized with other species. A survey of over 500 six-month-old, Scottish Blackface lambs from a single farm in Southwest Strathclyde identified 7 different categories of nematodes in the abomasum and small intestine. There were considerable differences among years and among nematodes in the prevalence and mean intensity of infection. Ostertagia circumcincta was present in nearly all lambs and judged by prevalence and intensity is one of the most successful of all parasitic nematodes. Each category of nematodes had a skewed distribution; most animals had relatively few worms but a small proportion had many worms. The variance of the number of nematodes in each category were approximately equal to the square of the mean. The counts of adult O. circumcincta followed a negative binomial distribution, but the negative binomial distribution did not provide a good description of the observed values for the other species. These other species had a lower prevalence and possibly some sheep were not exposed to infection. There was no significant genetic variation among lambs in the number of nematodes present and therefore the differences among these lambs were unlikely to be a consequence of genetic differences in host susceptibility. Lambs with increased numbers of one species were more likely to be have increased numbers of the other species, but the correlations were weak and may reflect covariation in exposure to different parasites.

Abomasum↗