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The ascaridoid nematode of cats from Kuala Lumpur, Malaysia, previously identified morphologically as Toxocara canis, was characterized using a molecular approach. The nuclear ribosomal DNA (rDNA) region spanning the first internal transcribed spacer (ITS-1), the 5.8S gene and the second internal transcribed spacer (ITS-2) was amplified and sequenced. The sequences for the parasite from Malaysian cats were compared with those for T. canis and T. cati. The sequence data showed that this taxon was genetically more similar to T. cati than to T. canis in the ITS-1, 5.8S and ITS-2. Differences in the ITS-1 and ITS-2 sequences between the taxa (9.4-26.1%) were markedly higher than variation between samples within T. canis and T. cati (0-2.9%). The sequence data demonstrate that the parasite from Malaysian cats is neither T. canis nor T. cati and indicate that it is a distinct species. Based on these data, PCR-linked restriction fragment length polymorphism (RFLP) and single-strand conformation polymorphism (SSCP) methods were employed for the unequivocal differentiation of the Toxocara variant from T. canis and T. cati. These methods should provide valuable tools for studying the life-cycle, transmission pattern(s) and zoonotic potential of this parasite.

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The nuclear ribosomal DNA (rDNA) region spanning the first (ITS-1) and second (ITS-2) internal transcribed spacers was sequenced for 15 taxa of ascaridoid nematodes. The length of the ITS-1 and ITS-2 sequences in the 15 taxa ranged from 392-500 bp and 240 348 bp, respectively. While nucleotide variation of 0-2.9% in the ITS-1 and/or ITS-2 sequences was detected within taxa where multiple samples were sequenced, significantly higher level of nucleotide difference (9.4-66.6%) was detected between the taxa, except for Ascaris suum and A. lumbricoides whose taxonomic status remains uncertain. These interspecific differences were linked with the considerable size differences (0-108 bp) in the rDNA spacers. Phenograms based on the genetic differences among the 15 taxa showed some concordance with previous classification schemes derived from morphological data.

Non-isotopic polymerase chain reaction (PCR)-based single-strand conformation polymorphism and sequence analyses of the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) were utilized to genetically characterise ascaridoids from dogs and cats from China by comparison with those from other countries. The study showed that Toxocara canis, Toxocara cati, and Toxascaris leonina from China were genetically the same as those from other geographical origins. Specimens from cats from Guangzhou, China, which were morphologically consistent with Toxocara malaysiensis, were the same genetically as those from Malaysia, with the exception of a polymorphism in the ITS-2 but no unequivocal sequence difference. This is the first report of T. malaysiensis in cats outside of Malaysia (from where it was originally described), supporting the proposal that this species has a broader geographical distribution. The molecular approach employed provides a powerful tool for elucidating the biology, epidemiology, and zoonotic significance of T. malaysiensis.

This article reviews contemporary concepts underlying the design of control strategies for the management of¯ea allergy dermatitis in dogs and cats. The limitations of palliative symptomatic approaches are noted, as is the fundamental requirement to dierentiate simple pulicosis from true hypersensitivity. In the latter case, eradication of¯eas from the aected animal and its surroundings has to be an essential aim. The dierent biological properties oered by modern chemotherapy are de®ned and the range of techniques for applying active compounds to the animal and its environment described. Factors for consideration when formulating control strategies and selecting chemotherapeutic agents are discussed in the context of the complexities of the¯ea life-cycle, the host-parasite relationship and client concerns.

In a longitudinal, population based study, overnight temperature recordings were made in the bedrooms of 152 babies aged 3-18 weeks and the insulation provided by their bedclothing was assessed. Outdoor temperatures for the study nights were also available.Parents applied more insulation on colder nights with lower bedroom temperatures than on warmer nights (mean 8.5 tog at 15°C minimum bedroom temperature falling to 4-0 tog at 25°C). For a particular temperature they also applied 2 tog more insulation in winter than in summer.The amounts ofbedclothing used in the home were compared with insulation levels predicted to achieve thermoneutrality over a similar range of environmental temperature from heat balance studies in young infants. They corresponded closely.The The first was a descriptive study of what was actually happening in our community. It was undertaken by measuring bedroom temperatures in babies' homes and by discovering the type and amount of clothing and bedding that babies were sleeping under, throughout the year and longitudinally over the first few months of life. In contrast the second study was carried out in a laboratory environment using a series of heat balance measurements on a smaller number of babies to determine how much insulation was required to achieve thermoneutrality over a range of environmental temperatures comparable to those in the home. Methods COMMUNITY METHODS