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The importance of companion animals in the daily lives of people, and the increasing incidence and severity of natural disasters impacting people and their animals, is very well documented. However, despite the advancement of companion animal response capabilities, decontamination remains an inconsistently implemented component of disaster response. The challenge for local authorities is their need for planning factors and protocols specific to companion animal decontamination which are generally lacking. Data is provided on the average time requirements, water use and containment resources necessary, and the personnel required to decontaminate (decon) a large number of companion dogs.
Methods:
Sixty-three lightly contaminated, medium weight, short to medium coat, highly tractable dogs (Labradors and Hounds) from a State facility colony were used to determine the water requirements, soap effectiveness, and time required to complete decon (washing/bathing). Data were collected over a 6-mo period using 2 personnel that were randomly assigned to wash the dogs. Difference in weight, bathing time, and water use between groups was evaluated using a 2-tailed 2-sample t-test for independent data.
Results:
The time and water requirements were significantly different between medium coated dogs and short coated dogs. On average, for a short coated dog, the amount of time to complete decon was 7 min, and the amount of water was 8-10 gal. For medium coated dogs, the time increased to 10-12 min to complete the process and 12-15 gal water.
Discussion:
The results of this study provide important insights emergency management planners, animal response team members, and community personnel tasked with implementation of mass decontamination of companion dogs following a natural or man-made disaster.
Deployment of law enforcement operational canines (OpK9s) risks injuries to the animals. This study’s aim was to assess the current status of states’ OpK9 (veterinary Emergency Medical Services [VEMS]) laws and care protocols within the United States.
Methods:
Cross-sectional standardized review of state laws/regulations and OpK9 VEMS treatment protocols was undertaken. For each state and for the District of Columbia (DC), the presence of OpK9 legislation and/or care protocols was ascertained. Information was obtained through governmental records and from stakeholders (eg, state EMS medical directors and state veterinary boards).
The main endpoints were proportions of states with OpK9 laws and/or treatment protocols. Proportions are reported with 95% confidence intervals (CIs). Fisher’s exact test (P <.05) assessed whether presence of an OpK9 law in a given jurisdiction was associated with presence of an OpK9 care protocol, and whether there was geographic variation (based on United States Census Bureau regions) in presence of OpK9 laws or protocols.
Results:
Of 51 jurisdictions, 20 (39.2%) had OpK9 legislation and 23 (45.1%) had state-wide protocols for EMS treatment of OpK9s. There was no association (P = .991) between presence of legislation and presence of protocols. There was no association (P = .144) between presence of legislation and region: Northeast 66.7% (95% CI, 29.9-92.5%), Midwest 50.0% (95% CI, 21.1-78.9%), South 29.4% (95% CI, 10.3-56.0%), and West 23.1% (95% CI, 5.0-53.8%). There was significant (P = .001) regional variation in presence of state-wide OpK9 treatment protocols: Northeast 100.0% (95% CI, 66.4-100.0%), Midwest 16.7% (95% CI, 2.1-48.4%), South 47.1% (95% CI, 23.0-72.2%), and West 30.8% (95% CI, 9.1-61.4%).
Conclusion:
There is substantial disparity with regard to presence of OpK9 legal and/or clinical guidance. National collaborative guidelines development is advisable to optimize and standardize care of OpK9s. Additional attention should be paid to educational and training programs to best utilize the limited available training budgets.
The aim of this study was to determine the causes of loss from active duty amongst German shepherd dogs in service with the New Zealand Police Dog Section. Current or previous police dog handlers (n = 149) completed a postal survey for each dog they had worked with during their career including their current dog. Causes of loss were categorised as either retirement, euthanasia whilst still in active duty, death from illness/natural causes, or being killed whilst on duty. Of 182 dogs with completed questionnaires, 48 dogs were still in service, leaving 134 that were retired (94), had been euthanased (24), had died (11) or had been killed (5). The mean and median age at loss for all dogs no longer in service was 6.6 years. The nominal age for planned retirement (8 years) was only reached by 40% of dogs. The single most important cause of retirement was the inability to cope with the physical demands of the job (61/94 dogs or 65%). Degenerative musculoskeletal disease was cited as the primary factor in 42/61 of these dogs (69%). When both retired and euthanased dogs where considered together, 27% were retired or euthanased due to back/spinal problems, and a high proportion of these were believed to have involved the lumbosacral joint. Greater research efforts should be targeted at identification of the factors that lead to degenerative musculoskeletal and lumbo-sacral disease to determine methods of lowering their incidence in police working dogs. Such research could lead to increasing the average working life and ‘in work’ welfare of a police German shepherd dog in New Zealand.
Undesirable behaviours (UBs) are common in dogs and can jeopardise animal and human health, leading to dog abandonment and euthanasia. Dogs exhibiting UBs may have compromised welfare from underlying emotional motivations for the behaviour (eg anxiety) or from the methods used by owners to resolve the problem (eg aversive techniques). The objective of this study was to estimate proportional mortality due to UBs and risk factors for death due to UBs, including death from road traffic accidents, in dogs under three years of age attending primary-care veterinary practices in England from 2009-2014. Cases were identified by searching de-identified electronic patient records from primary-care veterinary practices participating in the VetCompass Programme. The findings highlight that dogs under three years of age are at a proportionately high risk of death due to UBs (33.7%) compared with other specific causes of death (eg gastrointestinal issues: 14.5%). Male dogs had 1.40x the odds of death from UB compared with females. The proportional mortality from UB for male dogs where information on the cause of death was available was 0.41. Neutered dogs had 1.94x the odds of death due to a UB compared with entire dogs. Aggression was the most prevalent UB overall. Veterinarians had recommended referral in 10.3% of cases where dogs died due to exhibiting a UB and had dispensed nutraceutical, pheromone or pharmacological treatment to 3.0% of the UB cases that died. This study shows that undesirable behaviours require better preventive measures and treatment, through further research and education of veterinarians, other professionals within the dog industry and owners.
Understanding the factors associated with post-adoptive return in dogs (Canis familiaris) is important for reducing shelter return rates. The objective of this retrospective study was to identify factors detectable in shelters associated with post-adoptive return in an objective dog-centric analysis. The records of 959 dogs were evaluated via factor analysis of seven behaviour and seven physical variables which resulted in the extraction of six principal factors. Fear aggression, ongoing health concerns, separation anxiety, sex-specific aggression, and age effect on source were not found to significantly impact outcome. In particular, dog aggression risk (a factor composed of breed, size, and dog aggression) was found to be significantly higher in returned dogs. Since dog aggression risk is associated with post-adoptive return, this could help shelters to modify policies to either screen aggressive dogs from the adoption population or improve adoption counselling in an attempt to help lower return rates.
This chapter considers Virginia Woolf’s experiments in animal biography. It opens by presenting Woolf’s unpublished draft ‘Authorities’ note to Flush: A Biography (1933) as evidence of her knowing engagement with anthropomorphism and anthropocentrism, before going on to read that text alongside her first experiment in the genre, Orlando: A Biography (1928). In doing so, the chapter draws on correspondence between Woolf and Vita Sackville-West, as well as the latter’s rarely discussed book Faces: Profiles of Dogs (1961), to illustrate how canine companions take centre stage in their amorous discourse. It then turns to another overlooked intertext, Thomas Browne’s 1646 Pseudodoxia Epidemica, also known as Vulgar Errors, to show Woolf’s queering of his early modern belief that hares can change sex from female to male. Finally, the chapter places Flush in dialogue with a lesser-known dog biography the Woolfs considered for publication at the Hogarth Press (and which Woolf cleverly alludes to in her canine biography): Inordinate (?) Affection: A Story for Dog Lovers (1936) by composer, memoirist and suffragette Ethel Smyth.
Strongyloides stercoralis is an intestinal parasitic helminth that mainly affects humans and dogs throughout the world. Canine strongyloidosis is generally characterized by asymptomatic infection, with fatal disease in cases of immunodeficiency. This study was conducted in order to evaluate the global prevalence of S. stercoralis in dogs. Six electronic databases were searched for this purpose. The random effects model and 95% confidence intervals (CI) were applied to determine the overall and subgroup pooled prevalence. Heterogeneity was assessed by Cochran's Q test and I2 statistic. In total, 56 datasets from 50 studies from 1,202 peer-reviewed papers were included in the current meta-analysis. 20,627 dogs were assessed in 27 countries across six World Health Organization (WHO) regions. The global prevalence of S. stercoralis infection among dogs was 6% (95% CI 4–8%; 868/20,627). According to WHO regions, the estimated prevalence ranges 2% to 11% as follows: Western Pacific (11%, 0–31%); Africa (9%, 2–19%); America (6%, 3–11%); South-East Asia (5%, 1–13%)’ Europe (3%, 2–5%); and Eastern Mediterranean (2%, 0–6%). The pooled prevalence of S. stercoralis infection in dog owners was 7% (1–18%). The prevalence of S. stercoralis infection in studies based on serological assays was significantly higher than other techniques (29%, 20–39%). Younger female dogs, less than one year old, from rural areas had higher prevalence rates than their male counterparts, with no statistically significant differences. From this review, it is concluded that the low global prevalence of S. stercoralis in dogs may be strongly associated with low sensitivity diagnostic methods applied in most studies leading to the underestimation of infection rates. Therefore, the improvement of diagnostic techniques is recommended for precise evaluation of the disease.
Vitamin D insufficiency is associated with various disease processes. We determined whether consumption of a diet supplemented with HyD®, a 25-hydroxycholecalciferol (25(OH)D3) source, would safely increase plasma 25(OH)D3 concentrations in Golden Retrievers with low vitamin D status. We hypothesised that dietary supplementation with HyD® would rapidly increase and sustain plasma 25(OH)D3 levels in healthy Golden Retrievers with low vitamin D status compared with supplementation with vitamin D3. Of fifty-seven privately owned dogs recruited with written owner consent, eighteen dogs with low vitamin D status were identified and sorted between two groups to have similar initial plasma 25(OH)D3 concentrations, sex distributions, ages and body weights. Dogs of each group were fed a dry dog food supplemented with either 16 μg/kg of 25(OH)D3 as HyD® (n 10) or 81 μg/kg of cholecalciferol (D3) (n 8) for 4 months. Plasma 25(OH)D3 concentrations were determined monthly. A significant time effect (P < 0⋅001) and time by group interaction (P = 0⋅0045) were found for monthly determined plasma 25(OH)D3 concentrations. Dogs fed the HyD®-supplemented diet experienced a 40⋅5 % rise in plasma 25(OH)D3 values after 1 month (P < 0⋅001) and no change thereafter. Plasma 25(OH)D3 values of dogs supplemented with vitamin D3 did not increase (P > 0⋅05) and were less than values of dogs supplemented with HyD® (P = 0⋅044). With few exceptions, average haematologic, biochemical and urinalyses results remained within the reference range for both groups. Dietary supplementation with HyD® is sufficient to safely increase and sustain plasma 25(OH)D3 levels in healthy dogs.
The aim of this study was to compare different concentrations of soy lecithin (LEC0.01%, LEC0.05% and LEC0.1%) with egg yolk (Control) in cooling extenders during the storage of semen at 5ºC for 5 days. Twelve dogs (n = 12) were selected, and semen was cooled and assessed after 2, 24, 48, 72, 96 or 120 h. At each time point, sperm were analyzed for kinetic patterns (using computer-assisted sperm analysis), mitochondrial activity (3′3- diaminobenzidine assay), lipid peroxidation (TBARS assay), DNA fragmentation (SCSA®) and plasma and acrosome membrane integrity (eosin/nigrosin and fast green/rose Bengal stains, respectively). The Control group (1814.4 ± 197.2) presented the highest rates of lipid peroxidation at 120 h. Conversely, progressive motility (42.8 ± 4%), linearity (45.4 ± 1%), and VAP (88 ± 3%) were higher in the Control group. In addition, there was lower mitochondrial activity in the Control group at 72 h. Therefore, our data show that lecithin used at these concentrations was not able to maintain sperm viability at as high qualities as would egg yolk. Moreover, the decrease in high mitochondrial activity and the persistence of sperm motility may indicate a compensatory mechanism in canine spermatozoa (i.e., glycolytic pathway). Furthermore, these higher lipid peroxidation indexes could indicate the necessity for future therapy using extenders and antioxidants over a long cooling time for dog sperm.
Dogs suffer from skin associated issues with a disproportionate frequency, with consequent interest in providing nutrition to optimize their skin's natural defences. Linoleic acid (LA) is known as an essential nutrient in dogs and plays a critical part in the lipid component of skin barrier formation. Minimum requirements have been defined, primarily based on eliminating signs of deficiencies such as dry, flaky skin and inflammation. Zn has been shown as an important nutrient for maintaining epidermal health. This pilot study investigated whether there are skin barrier benefits from feeding both linoleic acid and Zn at levels significantly in excess of published minimum requirements. Eight Labrador retrievers were fed a diet containing 3.8 g/Mcal LA, 21 mg/Mcal Zn for 12 weeks to establish baseline conditions for all dogs (basal diet). After this period, for a further 12 weeks, the dogs were switched onto a diet containing 7.9 g/Mcal LA and 50 mg/Mcal Zn (test diet). Transepidermal water loss (TEWL measurements) were used as a measure of skin quality and integrity and were taken at the end of the initial feeding period, and at 6 and 12 weeks of the test feeding period. TEWL was reduced by 8.11 g/m2/h (P < 0.001) six weeks after instigation of the test diet, and by 7.52 g/m2/h (P < 0.005) at 12 weeks, compared to the levels (14.73 g/m2/h) at the end of the basal feeding trial period. The results showed evidence of improved barrier properties as TEWL when feeding higher levels of LA and Zn for six and 12 weeks.
In many regions of the world domestic dogs are free roaming and live in close relationship with humans. These free-roaming domestic dogs (FRDD) can cause public health problems such as dog bites and transmission of infectious diseases. To effectively control diseases transmitted by FRDD, knowledge on the dogs’ behaviour is required. To identify predictors of home range (HR) size, we collected global positioning system data from 135 FRDD living in eight Aboriginal and Torres Strait Islander communities in Northern Australia. The core HR size ranged from 0·17 to 2·33 ha and the extended HR size from 0·86 to 40·46 ha. Using a linear mixed effect model with a Restricted Maximum Likelihood approach, the dog's sex and reproductive status were identified as predictors of roaming. Non-castrated males had the largest HRs, followed by neutered females. Also, FRDDs were found to roam further during the pre- than the post-wet season. These findings have implications for infectious disease spread. Identification of risk groups for disease spread within a population allows for more targeted disease response and surveillance. Further investigation of predictors of roaming in other FRDD populations worldwide would increase the external validity of such studies.
Hair colouration in animals is controlled primarily by inherited factors, with a complex set of genes and genetic variants determining phenotypic expression. The colours in the hair shaft are created initially by the melanocyte cells within the hair bulb which produce and secrete two types of melanin into the hair cortex, black eumelanin and brown pheomelanin. Together these two pigments are responsible for creating the considerable diversity of colour seen in hair across the animal kingdom. In the absence of melanins the hair remains translucent, appearing white to the eye. Colour, or absence thereof, can only be imparted on a hair during its ‘anagen’ or growing phase. During the telogen (resting) phase the colour of the hair is relatively constant, notwithstanding effects of environmental influences such as UV in sunlight, or staining agents. A further environmental factor is nutrition. The intensity of black in the hair of both cats and dogs is known to be influenced by the dietary intake of certain amino acids such as phenylalanine (Phe) and tyrosine (Tyr). However the role of nutrition in hair pigmentation is generally poorly understood. This trial investigated the impact of diet on the commonly observed red discolouration of white coat in dogs. Two panels of 13 Swiss White Shepherd dogs were fed diets containing different concentrations of Phe + Tyr (test diet containing 3.02 g/Mcal versus control 4.82 g/Mcal) and copper (test diet containing 8.93 ppm versus control 13.28 ppm) for four months. Coat colouration was assessed via spectrophotometry using the CIE Lab colour space system (International Commission on Illumination). Dogs fed the reduced Phe + Tyr and copper showed significantly less red coat pigmentation (a* parameter) by the end of the feeding study (P < 0.02). It was concluded that the level of Phe + Tyr not only affects black but also white coat in dogs. Diet can therefore exert an influence on multiple aspects of coat pigmentation.
Obesity is arguably the biggest health and welfare issue affecting pet dogs. Although successful weight loss has health benefits, current strategies are far from ideal. Many obese dogs that start a weight programme fail to lose weight, or subsequently regain the weight they have lost. Given that current weight loss strategies are not perfect, clinicians need to focus carefully on tailoring the programme, perhaps setting a pragmatic target for weight loss, so as to ensure the benefits are maximised. This review will summarise key findings from recent clinical research into pet obesity, and present a framework for improving success, by better tailoring weight management regimens and end points to the individual.
Very little research into genetic diversity of Italian native dog breeds has been carried out so far. In this study we aimed to estimate and compare the genetic diversity of four native Italian shepherd dog breeds: the Maremma, Bergamasco, Lupino del Gigante and Oropa shepherds. Therefore, some cosmopolitan dog breeds, which have been widely raised in Italy for a long time past, have also been considered to check possible influence of these dog populations on the Italian autochthonous breeds considered here. A total of 212 individuals, belonging to 10 different dog breeds, were sampled and genotyped using 18 autosomal microsatellite loci. We analyzed the genetic diversity of these breeds, within breed diversity, breed relationship and population structure. The 10 breeds considered in this study were clearly genetically differentiated from each other, regardless of current population sizes and the onset of separate breeding history. The level of genetic diversity explained 20% of the total genetic variation. The level of HE found here is in agreement with that found by other studies. The native Italian breeds showed generally higher genetic diversity compared with the long established, well-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can be utilized in the organization of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability.
The nematode Angiostrongylus vasorum is becoming more widely recorded globally, and is of increasing concern as a cause of disease in dogs. Apparent geographic spread is difficult to confirm due to a lack of standardized disease recording systems, increasing awareness among veterinary clinicians, and recent improvements in diagnostic technologies. This study examines the hypothesis that A. vasorum has spread in recent years by repeating the methods of a previous survey of the fox population. The hearts and lungs of 442 foxes from across Great Britain were collected and examined by dissection and flushing of the pulmonary circulation and microscopic inspection of tracheal scrapes. Sampling and parasite extraction methods were identical to an earlier survey in 2005 to ensure comparability. Prevalence of A. vasorum was 18·3% (exact binomial confidence bounds 14·9–22·3), compared with 7·3% previously (5·3–9·9, n = 546), and had increased significantly in most regions, e.g. 7·4% in the Northern UK (previously zero) and 50·8% in the south-east (previously 23·2%). Other nematodes identified were Crenosoma vulpis (prevalence 10·8%, CI 8·1–14·2) and Eucoleus aerophilus (31·6%, CI 27·3–36·2). These data support the proposal that A. vasorum has increased in prevalence and has spread geographically in Great Britain.
High-throughput DNA sequencing techniques allow for the identification and characterisation of microbes and their genes (microbiome). Using these new techniques, microbial populations in several niches of the human body, including the oral and nasal cavities, skin, urogenital tract and gastrointestinal tract, have been described recently. Very little data on the microbiome of companion animals exist, and most of the data have been derived from the analysis of the faeces of healthy laboratory animals. High-throughput assays provide opportunities to study the complex and dense populations of the gut microbiota, including bacteria, archaea, fungi, protozoa and viruses. Our laboratory and others have recently described the predominant microbial taxa and genes of healthy dogs and cats and how these respond to dietary interventions. In general, faecal microbial phylogeny (e.g. predominance of Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria) and functional capacity (e.g. major functional groups related to carbohydrate, protein, DNA and vitamin metabolism; virulence factors; and cell wall and capsule) of the canine and feline gut are similar to those of the human gut. Initial sequencing projects have provided a glimpse of the microbial super-organism that exists within the canine and feline gut, but leaves much to be explored and discovered. As DNA provides information only about potential functions, studies that focus on the microbial transcriptome, metabolite profiles, and how microbiome changes affect host physiology and health are clearly required. Future studies must determine how diet composition, antibiotics and other drug therapies, breed and disease affect or are affected by the gut microbiome and how this information may be used to improve diets, identify disease biomarkers and develop targeted disease therapies.
Dogs participating in endurance exercise, including herding, hunting and racing have a greater energy requirement and may be more susceptible to nutrient depletion, electrolyte imbalance and metabolic stress. The objective of the present study was to investigate the acute response to unstructured mixed exercise in American Foxhounds fed a nutrient-fortified endurance diet. Thirty-nine adult Foxhound dogs (median age: 5·0, range: 2–10 years and median body weight (BW): 36·4, range: 24·9–49·5 kg) were allotted to a standard performance diet (Control) or nutrient-fortified endurance diet for adult dogs (Test). Dogs were balanced by sex, age, BW and athletic performance between diets. All male dogs were intact, whereas all the female dogs were spayed. After 80 d on diet, blood samples were collected via jugular puncture at baseline (0 h), and at 3 and 25 h post-exercise (mean: 17·7 (sem 0·92) km run over 2–3 h). Plasma taurine concentration and complete amino acid (AA) profile, serum chemistry and creatine kinase were measured. Serum chemistry profile remained within normal ranges throughout the study. A significant (P < 0·05) diet by time interaction was observed for calcium, alkaline phosphatase and most AA. Plasma taurine and most essential AA were increased (P < 0·05) after exercise and remained greater (P < 0·05) in dogs fed the Test diet, including the branched-chain AA (isoleucine, leucine and valine). Creatine kinase increased (P = 0·01) after 3 h and returned to baseline after 25 h post-exercise, but was not altered by diet. These data indicate that dogs undergoing a moderate bout of exercise did not suffer from electrolyte imbalance, and that a nutrient-fortified diet resulted in greater plasma taurine and essential AA concentrations.
Eosinophils play a crucial role in the inflammatory response in conjunction with both innate and adaptive immunity. Eosinophils have long been recognized as inflammatory leukocytes that are particularly important in patients with parasitic infestations. However, recent studies in veterinary medicine demonstrate a number of canine eosinophilic gastrointestinal (GI) disorders unrelated to a parasitic infestation. Although the underlying pathophysiology behind eosinophilic infiltration of the canine GI tract remains uncertain, medical intervention aiming to decrease the activation of eosinophils seems effective in reducing symptoms and preventing organ damage. This review focuses on the biology of eosinophils and their products. It describes, the composition of eosinophil granules, mechanisms of eosinophil activation, and eosinophil-related disease processes leading to organ damage. Even though the main clinical signs of canine eosinophilic gastroenteritis, vomiting and diarrhea, are similar to those of other types of gastroenteritis, the clinical response and prognosis are worse for this condition. The clinical signs and diagnostic approach for eosinophilic GI disorders are described and compared between canine and human patients for each region of GI tract, from the esophagus to the colon. Moreover, the current treatments for this syndrome in canine and human patients are summarized and paralleled. The comparative study of canine and human patients with eosinophilic gastroenteritis will advance the understanding of this syndrome in both species and may lead to the development of novel treatment strategies.
This study was conducted to determine the seroprevalence of anti-Neospora caninum antibodies and to investigate the risk factors related to seroprevalence in dogs from urban and rural areas with distinct economic activities (milk and coffee production) in Minas Gerais state, Brazil. For this purpose, blood samples from 703 dogs were collected and questionnaires addressing epidemiological aspects were completed by dog-owners. The sera were analysed for anti-N. caninum antibodies by indirect fluorescent antibody tests (IFAT ⩾ 1:50). Association between epidemiological aspects and seropositivity in dogs was evaluated with multivariate logistic regression models. A total of 80 (11·4%) dogs tested positive for N. caninum. In the multivariate logistic regression models, dogs aged >4 years, dogs used as guard dogs, dogs that spontaneously hunt, and history of bovine abortion were found to be greater risk factors for canine N. caninum infection. When we considered only dogs from rural areas, an association with seroprevalence was seen for milk farms, dogs not fed with commercial food, dogs that hunt, and dogs used as guard dogs.
This study compared the fatty-acid profiles of Brucella canis blood culture isolates obtained from infected dogs in the UK, Germany, Japan, South Africa, Peru, Mexico, Colombia, and Argentina, and from a human clinical case in Argentina, to a bank of isolates obtained from canine outbreaks in the USA. Analysis of a total of 42 B. canis isolates and one reference strain found a marked variation within the species. Fatty-acid analysis showed that only the isolates from Argentina, Colombia, and Mexico, which included the human B. canis isolate, contained a specific fatty acid, 19:0 cyclopropane (lactobacillic acid), w8c (cis-11,12-methylene octadecanoic acid), and that this fatty acid, when present, made up a large percentage of overall fatty-acid content. Prior to this study, the cellular fatty-acid 19:0 cyclopropane had been identified in all of the species of Brucella considered to be pathogenic to humans (B. abortus, B. melitensis, B. suis) except for B. canis. Discovering that this fatty acid not only occurs in B. canis, but also that it is only present in some strains of the species provides a new focus for investigations aimed at identifying the cause of reported geographical variability in human B. canis infection, and at finding predictors of biological behaviour and human pathogenicity within this Brucella species.