Prevalence and shedding patterns of Campylobacter spp. in longitudinal studies of kennelled dogs

Dog ownership is considered a risk factor for campylobacteriosis in humans. This study investigated the prevalence and shedding of Campylobacter spp. in kennelled dogs. Faecal samples (n=399) were collected in longitudinal studies from 52 dogs in two kennels. Campylobacter spp. were isolated using charcoal-based selective agars and direct PCR. The prevalence of Campylobacter spp. in dogs in boarding kennels ranged from 46% (95% CI 22, 72) on entry, to 50% (95% CI 30, 70) overall, and in dogs in 'rescue' kennels from 68% (95% CI 49, 84) on entry to 73% (95%, CI 56, 87) overall. C. upsaliensis was isolated from 62% (95% CI 48, 73) of the dogs, whilst C. jejuni was isolated from 15% (95% CI 7, 26) of animals. The majority of infected dogs entered the kennels already carrying Campylobacter spp., and remained infected throughout their stay. However, in some cases, shedding appeared to commence after kennelling. Given that the prevalence of C. upsaliensis and C. jejuni was relatively high in dogs from both boarding and rescue kennels, such animals may pose a zoonotic risk.     

Nutritional value of a highly digestible sorghum cultivar for meat-type chickens

The nutritional value of a newly discovered sorghum mutant cultivar (P851171), with high in vitro protein digestibility, was compared to those of corn and two normal sorghums (P721N and 611Y) in two chick feeding trials. Although 8-20 day protein efficiency ratios and net protein ratios of all three sorghums were inferior to those of corn, P851171 and 611Y had markedly greater mean true amino acid digestibilities (TAAD) than either corn or P721N. In a subsequent 42-day experiment, all three sorghums supported weight gains equal to those of the corn-fed chicks. Feeding suboptimal levels of dietary protein resulted in reduced weight gains and no observed benefits of P851171 or 611Y. Furthermore, chicks fed P851171 exhibited poorer feed/gain values as compared to those fed the other cereals. It is possible that the starch content/carbohydrate profile of P851171 was inferior to that of the other sorghums, which offset its superior TAAD and resulted in poorer broiler performance.     

A Preliminary Investigation of Ozone Concentrations on the Lizard Peninsula Cornwall,U.K. using Continuous Monitoring and Diffusion Tubes

The Lizard Peninsula is an isolated area of unique and sensitive ecology and the occurrence of damaging ozone concentrations over the peninsula in spring challenges the successful sustainable management of the area. Ozone concentrations over Goonhilly Downs on the Lizard Peninsula in Cornwall were measured in spring 2002 using continuous monitoring and spatial mapping (diffusion tubes). Data obtained using a continuous ozone monitor (1/03/02 to 31/03/02) showed that the AOT40 5-day values were in a range from 2 to 800 μg m^-3 hr (AOT40 is the sum of the differences between the measured hourly ozone concentration (μg m^-3) and 80 μg m^-3 (when the concentration exceeds 80 μg m^-3) for the hours when global radiation exceeds 50 Wm^-2). Contour mapping of ozone concentrations measured with diffusion tubes suggested that over a 2 km² sampling area significant microscale variations were occurring with ozone concentrations ranging between 48–129 μg m^-3 for one two-week period and 62–210 μg m^-3 for the other.Unusually high diurnal variations in ozone concentrations were also observed at Goonhilly. It is thought that temperature inversions caused the entrapment of ozone at the surface level.     

Swarming of bats at underground sites in Britain—implications for conservation

We investigated the extent of visitation of underground sites during late summer and autumn (‘swarming’) by bats. Bats were captured at eight cave, mine and tunnel sites in southern England over 6 years (1995-2000). A total of 3077 bats representing 11 of Britain's 16 species was caught. Myotis bats predominated in autumn. At some sites these are rarely seen during winter hibernation counts. Myotis nattereri and M. daubentonii were most common. However, species composition changed seasonally. At one site, M. brandtii dominated early in the season and at all sites peak activity of M. daubentonii was earlier than in M. nattereri. Relatively high numbers of internationally vulnerable species such as M. bechsteinii and Barbastella barbastellus were recorded. There was a strong male bias in captures of swarming species. Swarming probably has an important reproductive function, most males are reproductively active at this time and such sites may be important for outbreeding. Due to this and the large number of individuals and species concerned, the conservation of ‘swarming sites’ is vitally important. Clearly swarming sites merit special consideration in conservation management strategies for cave-dwelling bats.     

Akabane disease in sheep

Perinatal lamb mortality, associated with malformations of the CNS due to Akabane viral infection, occurred in 4 of 9 flocks of ewes lambing on 3 farms between 26 May and 14 November, 1976. Cases were restricted to ewes conceiving prior to the second week of March and lambing between 26 May and 19 July. As judged by seroconversion in sentinel flocks on 2 of the farms, field infection with Akabane virus occurred mainly between mid-February and mid-April. Malformations of the CNS occurred in 42.5%, 51.2%, 100% and 31.0% of the dead lambs examined in the affected flocks respectively. Prevalence in the 4 affected flocks, expressed as the proportion of ewes lambing which delivered at least one malformed foetus, was 6.1%, 8.4%, 88.9% and 5.7% respectively. Lamb mortality due to malformations of the CNS was 7.1%, 5.5%, 92.3% and 5.7% of lambs born. Age-specific prevalence was calculated for 3 of the 4 flocks and 2-year-old ewes accounted for 71.4% and 76.9% of total cases respectively in 2 flocks, whereas in one flock malformations occurred at equivalent frequencies throughout several older age groups. Birthweights of affected lambs were usually significantly lighter than those of unaffected lambs of similar sex and birth-type, and their mean duration of gestation was slightly, and significantly, prolonged. Micrencephaly (88.1% of cases) and hydrocephalus (68.7% of cases) were the outstanding pathological features of the malformations with hydranencephaly, microgyria, porencephaly and attenuation of the spinal cord occurring at much lower frequencies.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ascarid infections of cats and dogs

The ascarids Toxocara canis, Toxocara cati, and Toxascaris leonina are probably the most common gastrointestinal helminths encountered in small animal practice. Both T. canis and T. cati can cause serious disease in kittens and puppies; T. leonina is generally less pathogenic. Prenatal transmission assures that virtually all puppies are born infected with T. canis. Transmammary transmission is probably the major route of infection for kittens with T. cati. In addition, all three species of worm produce resistant eggs and use paratenic hosts to facilitate transmission. Much is now known about the complex biology and life history of T. canis. However, many questions, such as those concerning the mechanisms of larval survival within host tissues and of larval reactivation and migration during pregnancy, await further study. The mechanism of resistance to ascarid infections in cats and dogs has not been clearly defined. Ascariasis is traditionally thought to be a disease of young animals, with older animals being considered immune. However, at least in the case of T. canis, adult dogs can be repeatedly infected. A wide range of anthelmintics is available with extremely high efficacy against patent ascarid infections. The problem of prenatal infection with T. canis may be overcome by strategic use of the newer benzimidazole-carbamates, and the production of ascarid-free puppies now seems possible. However, complete larvicidal activity against somatic stages has not been convincingly demonstrated. Visceral larva migrans-like syndromes are now being recognized in dogs and cats. In addition, visceral larva migrans in children due to T. canis continues to be a significant zoonotic disease in North America and underscores the need for the veterinary profession to control ascarid infections in cats and dogs at every opportunity.