Efficiency of working dogs undergoing a new Human Familiarization and Training Program

The study of human-dog interaction has increased over the past several years. It has been demonstrated that dogs can use a number of human social cues to successfully accomplish a task, and that they do so better than apes. Many authors agree that these abilities are a result of 10,000 years of domestication by humans. Domestication may have genetically predisposed dogs to accurately recognize human communication signals. However, only a few authors have studied the performance of working dogs, implying recognition of human communication signals. Haverbeke et al. (2008) found that military working dogs do not always perform as they are expected to. To investigate this finding, we studied the performance of obedience and protection work exercises between 2 groups of dog-handler teams: a control group (CG), trained using the current training method used by the Belgian Defense, and an experimental group (EG) that underwent a new human familiarization and training program. During obedience and protection work exercises, EG teams obtained better results than CG teams and EG dogs exhibited a higher body posture than CG dogs. The results suggest that even if dogs are genetically predisposed toward the recognition of human communication signals, this aptitude alone does not explain the dogs' performance and their interactions with humans in this study. Regular training combined with positive dog-handler interaction is also required to increase the dog-handler (DH) team's performances.     

Intraocular and Cardiopulmonary Effects of Low-dose Mannitol in the Dog

Fatal complications have been reported during anesthesia in dogs that received a standard (1–2 g/kg IV) dose of mannitol during intraocular surgery. A lower dose (0.25 g/kg IV), which had been shown to reduce intracranial pressure in humans, was evaluated during halothane anesthesia in dogs. There were no significant changes in intraocular pressure (IOP) or cardiovascular variables. This lower dose (0.25 g/kg IV) did not reduce IOP and would not be of benefit in dogs undergoing intraocular surgery.     

A型流感病毒致病性及跨种间传播的分子生物学基础

A型流感病毒在温血动物中广泛存在,也是目前导致人类和各种动物流感疾病的主型。在自然情况下流感病毒感染的宿主范围有一定的特异性,分离自人的流感病毒一般不能在鸡、鸭等禽类体内复制,同样禽流感病毒在灵长类动物体内的复制能力也极差。但近年来不断发生禽流感病毒（包括H5N1,H9N2,H7N7亚型病毒）直接传染给人的事件,而2009年爆发的人类的H1N1流感的病原则是猪源流感病毒重组而来。研究证实,流感病毒的致病性及跨种间传播的深层原因是病毒分子结构差异及其与宿主细胞相互作用。病毒多种结构蛋白和非结构蛋白某些功能位点上氨基酸的差异是病毒致病性及其跨中传播的分子生物学基础。     

Interspecies transmission of equine influenza virus (H3N8) to dogs by close contact with experimentally infected horses

In horse populations, influenza A virus subtype H3N8 (equine influenza virus, EIV) is a very important pathogen that leads to acute respiratory disease. Recently, EIV has emerged in dogs, and has become widespread among the canine population in the United States. The interspecies transmission route had thus far remained unclear. Here, we tested whether the interspecies transmission of EIV to dogs could occur as a result of close contact with experimentally EIV-infected horses. Three pairs consisting of an EIV-infected horse and a healthy dog were kept together in individual stalls for 15 consecutive days. A subsequent hemagglutination inhibition test revealed that all three dogs exhibited seroconversion. Moreover, two of the three dogs exhibited virus shedding. However, the dogs exhibited no clinical signs throughout the course of the study. These data suggest that the interspecies transmission of EIV to dogs could occur as a result of close contact with EIV-infected horses without clinical symptoms. Although the interspecies transmission of EIV is unlikely to become an immediate threat to canine hygiene, close contact between EIV-infected horses and dogs should be avoided during an EI epidemic.     

Bovine and canine acute phase proteins

Acute phase proteins are serum proteins which increase in concentration during the acute phase response to inflammation or infection. The response occurs in all animals, but in different species the response of individual proteins can be significantly different. Of the numerous acute phase proteins which have been identified in humans, a number have been examined in cattle and dogs but usually on an individual basis with little reference to their part in the acute phase response. Biochemical, physiological and clinical investigations into haptoglobin, fibrinogen, ₁-proteinase inhibitor, ceruloplasmin, seromucoid and C-reactive protein of cattle and dogs have therefore been reviewed with the emphasis on their role in this response to tissue damage.     

Risk of infection with Leishmania spp. in the canine population in the Netherlands

The dog is the main reservoir of Leishmania infantum, the causative agent of visceral leishmaniasis (VL) in humans in Southern Europe. In order to identify the risk of dogs from a Leishmania non-endemic area traveling to a Leishmania-endemic area becoming infected and the risk of transmitting infection to humans in non-endemic areas an investigation was performed, in which the results of a questionnaire were combined with the results of a serologic survey. The questionnaire was sent to 1478 at random chosen families in the Netherlands. Of the 59.0% responders 28.0% had one or more dogs and 4.8% of these dogs had visited Southern Europe during the summer period of that year. On a total population of 1,200,000 dogs in the Netherlands, this means that each year some 58,000 dogs are at risk of being exposed to a Leishmania infection in Southern Europe. During the period 1990-1992 blood was collected for serology in 1911 dogs presented to the Utrecht University Clinic because of clinical problems not related to leishmaniasis, of which 434 had been in Southern Europe in the foregoing years. None was serologically positive. From these data it can be deduced that the highest chance to obtain leishmaniasis during a vacation in Southern Europe is mathematically less than 1/434 or less than 0.23%. Serology was also performed during the period 1989-1993 in 597 dogs that had been in Southern Europe and were suspected of leishmaniasis. Titers were positive in 145 of these samples. Sixty-four of these dogs were born in the Mediterranean and had been imported into the Netherlands. Excluding these imported dogs, it was calculated that at least 0.027% of the 58,000 dogs yearly taken to Southern Europe during holidays become infected with Leishmania. In order to establish the risk of disease transmission for people in close contact with an infected dog, serum samples of owners and house mates of 37 dogs with leishmaniasis were tested. All 112 sera tested negative. It was concluded that the risk to get leishmaniasis was between 0.027% and 0.23% for the dog when taken to Southern Europe during vacation, and that the risk for owners in non-endemic areas to get leishmaniasis from an infected dog is minimal.     

Evolutionary approach to communication between humans and dogs

Dogs and humans have been sharing a common environment for a long time. Some aspects of their social interaction are described as communication in which members of both species influence each other’s behaviour by special behaviour signals. Recent research is aimed at providing an evolutionary account for the emergence of communicative interactions between dogs and people. The present review summarizes how carefully applied experimental methods can be utilised to answer such research questions, in order to separate different processes that may underlie the mental abilities in dogs.     

Spatial and temporal comparison of selected cancers in dogs and humans, Michigan, USA, 1964-1994

Our aim was to investigate the geographic and time distributions of some biologically similar neoplasms in dogs and humans living in Michigan, USA, between 1964 and 1994. Our objective was to describe and compare the patterns of cancer in the two species while assessing the strength and dependence of those patterns. In this retrospective, registry-based study, histologically confirmed incident human and canine cancer cases were mapped, and second-order (K function) spatial analysis and one-dimensional nearest neighbor temporal analysis were performed on residence addresses and dates of hospital discharge/diagnosis. Included in the study were all 528 incident cases of canine lymphosarcoma, mammary adenocarcinoma, melanoma and spindle-cell sarcomas diagnosed at a veterinary teaching hospital between 1964 and 1994 having residence addresses in Ingham, Oakland, and Wayne Counties; and a stratified random sample of 913 incident human cases of comparable cancers diagnosed during the same time period from the same counties. Results suggest that processes determining spatial aggregation of cases in dogs and humans were not independent of each other, did not act uniformly over different geographic areas, operated at spatial scales <2000 m regardless of species, and tend to act upon dogs more strongly at shorter distances than on humans. Little evidence of interspecies concurrence of temporal clustering was found.     

Evaluation of the risks of shedding Salmonellae and other potential pathogens by therapy dogs fed raw diets in Ontario and Alberta

Dogs that participate in animal-assisted interventions (AAIs), often called 'therapy dogs', commonly interact with humans whose immune systems are not functioning optimally. The advisability of feeding raw meat (including poultry) to these animals remains a highly contentious issue, in spite of increasing evidence that raw meat is frequently contaminated with Salmonella. We set out to determine if consuming raw meat influences the risk of therapy dogs shedding Salmonella and other pathogens. Two hundred healthy therapy dogs from Ontario and Alberta were enrolled. Between May 2005 and November 2006, fecal specimens were collected from each dog every 2 months for 1 year, along with a log of places visited, antimicrobial use within the home, dog health status and diet. Specimens were cultured for Salmonella, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), extended-spectrum cephalosporinase (ESC) Escherichia coli and Clostridium difficile. Forty (20%) of the dogs were reported to have been fed raw meat at some point during the year. The incidence rate of Salmonella shedding in the raw meat-fed dogs was 0.61 cases/dog-year, compared with 0.08 cases/dog-year in dogs that were not fed raw meat (P < 0.001). Controlling for therapy dog group, the repeated measures, and pig ear consumption and diarrhoea in the 2 months prior to specimen submission, dogs that consumed raw meat were significantly more likely to test positive for Salmonellaat least once during the year than dogs that did not eat raw meat [odds ratio (OR) 22.7; 95% confidence interval (CI) 3.1-58.8; P < 0.001]. Specific Salmonella serovars were more common among dogs that consumed raw meat versus those that did not include S. Typhimurium, S. Heidelberg and S. Kentucky. Raw meat consumption was also significantly associated with shedding ESC E. coli (OR 17.2; 95% CI 9.4-32.3). No associations between C. difficile, MRSA or VRE and consumption of raw meat were detected. We recommend that dogs fed raw meat should be excluded from AAI programmes, particularly when the programmes involve interaction with humans at high risk of infection or adverse sequelae attributable to infection. Furthermore, although AAI dogs may not be representative of the general population of dogs, we also recommend that feeding of raw meat to dogs is to be avoided in homes where immunocompromised people live.     

Behavioral problems of geriatric dogs and cats

Dogs and cats that have been perfectly acceptable pets for many years may develop behavioral problems with old age. Most often these problems develop in animals that have never been very well behaved but have been tolerated by the owners until the problem has somehow exacerbated secondary to some other geriatric problem. The behavioral problems of old dogs most likely to be encountered by the practitioner are those of deaf dogs, dogs that house-soil because of renal, cardiovascular or gastrointestinal problems, and dogs that are aggressive because of a change in the number of animals or humans in the household or that are aggressive secondary to a chronic painful condition such as arthritis. Common feline problems may concern changes in the cat's environment. The treatment of behavioral problems of old animals is similar to the treatment of the problems of young animals, except that the physical limitations and disabilities of the old, usually ill, animal must be considered. Owners should be advised of the behavioral problems that may occur secondary to degenerative diseases and also be persuaded to keep social and environmental changes to a minimum in an old animal's life.     

Evolutionary approach to communication between humans and dogs

Dogs and humans have been sharing a common environment for a long time. Some aspects of their social interaction are described as communication in which members of both species influence each other’s behaviour by special behaviour signals. Recent research is aimed at providing an evolutionary account for the emergence of communicative interactions between dogs and people. The present review summarizes how carefully applied experimental methods can be utilised to answer such research questions, in order to separate different processes that may underlie the mental abilities in dogs.     

Dogs as vectors of Streptobacillus moniliformis infection?

Rat bite fever is a bacterial zoonosis transmitted through the bite of rats. One of the two etiological agents that cause rat bite fever is Streptobacillus moniliformis. Rat bite fever is rare and very likely under diagnosed but occurs worldwide. Other animals, like dogs and cats that have mouthed a rat are often mentioned in the literature as potential risks for the attraction of rat bite fever. However, rat bite fever caused by the bite of a dog or cat has very seldom been documented. Therefore, to identify the possible risk for humans to become infected with S. moniliformis after having been bitten by a dog that has been in contact with rats, the presence of S. moniliformis in the mouth of these dogs was tested with molecular methods. Swabs taken from the mouth of 18 dogs with proven contacts with rats were tested for the presence of S. moniliformis DNA by PCR. An amplicon of the right size was obtained in 10 of the 18 dogs. Nucleotide sequencing of five amplicons of PCR positive samples demonstrated the presence of S. moniliformis DNA in the mouth of three dogs. A bite by these dogs therefore might infect humans with S. moniliformis and cause rat bite disease.     

Symptomatic granular cell tumor involving the pituitary gland in a dog: a case report and review of the literature

A granular cell tumor involving the pituitary gland, optic chiasm and ventral pyriform lobes was discovered in a 12-year-old Labrador Retriever. Clinical signs included acute blindness, seizures, ataxia, weakness, and behavioral changes. The diagnosis was established by histopathologic and ultrastructural examination of neoplastic tissues collected at necropsy. Granular cell tumors involving the central nervous system are well documented in humans but rarely have been described in dogs. The location of the neoplasm and the clinical symptoms seen in this dog closely parallel those of a rare syndrome in humans commonly described as symptomatic parasellar or pituitary granular cell tumors. The cell of origin for these tumors is still highly debated, and attempts to characterize human granular cell tumors through immunohistochemistry have produced conflicting results. An immunohistochemical profile of this neoplasm revealed focal positive staining for vimentin with a lack of staining for neuron-specific enolase, glial fibrillary acidic protein, S-100, and synaptophysin. All neoplastic cells were strongly positive with the periodic acid-Schiff reaction.     

Characterization of methicillin-resistant Staphylococcus aureus CC398 obtained from humans and animals on dairy farms

In this study MRSA isolates from dairy farms were investigated for their genetic relationships and antimicrobial susceptibility. In total, 125 MRSA isolates from 26 dairy farms were studied, including isolates from milk samples (n=46), dairy cattle (n=24), calves (n=6), dust samples from pig (n=16) and veal calf sheds (n=1), dogs (n=2), a horse, a sheep and humans (n=28). CC398-specific PCRs, spa typing, SCCmec typing and ApaI macrorestriction analysis were conducted. Susceptibility testing was performed by broth microdilution. All 125 isolates belonged to CC398. Eight spa types (t011, t108, t034, t567, t1184, t1451, t2287 and t3934) were detected. SCCmec elements of types IV (n=48) and V (n=67) were identified with 10 isolates being non-typeable. Six main macrorestriction patterns - with up to 23 sub-patterns - and twelve resistance patterns were identified. Sixty-eight isolates showed a multiresistance phenotype. Farm-by-farm analysis revealed different scenarios: in some farms, the MRSA CC398 isolates from dairy cattle, humans, pig sheds and/or sheep were indistinguishable suggesting an interspecies exchange of the same MRSA CC398 subtype. In other farms, several MRSA CC398 subtypes were detected in different host species/sources with occasionally even more than one MRSA CC398 subtype from the same host species/source. These latter results may suggest that either different MRSA subtypes associated with humans or animals have been imported into the respective farm or that one MRSA CC398 strain has undergone diversification, reflected by more or less expanded changes in PFGE patterns, spa type or resistance pattern, during colonization of different hosts on the same farm.     

Distinct antigen recognition pattern during zoonotic visceral leishmaniasis in humans and dogs

Leishmania infantum is a causative agent of endemic zoonotic visceral leishmaniasis (VL) in regions of South America and the Mediterranean. Dogs are the major reservoirs for L. infantum in these regions, and control of disease in dogs could have a significant impact on human disease. Although dogs share many symptoms of VL with humans as a result of L. infantum infection, they also show some unique clinical manifestations, which are often a combination of visceral and cutaneous leishmaniasis, suggesting different mechanisms of disease development in dogs and humans. Here, we compare antibody responses of dogs and humans with VL to various defined leishmanial antigens. Parasite lysate and K39, the two most commonly used antigens for serodiagnosis of VL, detected the highest levels of antibodies in both humans and dogs with VL, whereas the recognition patterns of these antigens were distinct between the hosts. Among other defined antigens tested, LmSTI1 and CPB detected higher levels of antibodies in dogs and humans, respectively. These results indicate there is a difference between humans and dogs in antigen recognition patterns during VL. We infer that different strategies may need to be used in development of vaccines and diagnostics for humans and for dogs. In addition, we show a correlation between antibody titers to several antigens and severity of clinical symptoms during canine VL.     

The canine RAD51 mutation leads to the attenuation of interaction with PALB2

RAD51 forms a complex with BRCA2 and plays a central role in the DNA damage response pathway that is associated with homologous recombination. The structures of RAD51 and its homologues are highly conserved from prokaryotes to higher eukaryotes. Although a large number of BRCA2 mutations have been reported, there are only a few reports on the mutations of RAD51, which have been shown in humans and dogs. However, several mutations of canine RAD51 were identified from mammary gland tumour tissues in a recent study. Some of these mutations seem to have an influence on the homo‐oligomerization or interaction with “Partner and localizer of BRCA2” (PALB2). In this study, we cloned the canine PALB2 homologue and investigated the effect on its interaction with the RAD51 mutants to evaluate the alteration in the function of RAD51 mutants. The A209S and T225S mutants of RAD51 show an attenuation of the interaction between RAD51 and PALB2. These results indicate that the canine RAD51 mutations can potentially alter the homologous recombination pathways in response to DNA damage in dogs.     

Clinical significance of plasma mannose concentrations in healthy and diabetic dogs

Circulating levels of monosaccharides can act as a reflection of systemic glucose/ energy metabolism. Characteristic changes observed in these levels can be seen in patients with diabetes and other metabolic disorders. There have been a few reports describing the significance of mannose metabolism as an energy source under physiological and pathological conditions. However, the relationship between circulating levels of mannose and the pathophysiology of diabetes mellitus are unknown in dogs. This study examined circulating levels of mannose between healthy control and diabetic dogs and evaluated the clinical significance of mannose levels in dogs. Diabetic dogs demonstrated a higher circulating level of mannose in comparison to normal healthy control dogs. Plasma mannose was positively correlated with plasma glucose and fructosamine, respectively. Interestingly, plasma mannose levels were affected by plasma insulin levels. In the context of feeding and glucose tolerance tests, plasma mannose levels responded to changes in circulating insulin levels. Circulating plasma mannose levels decreased after feeding in both control and diabetic animals in spite of observed insulin level differences. However, when glucose tolerance tests were given, a positive correlation between mannose levels and insulin levels was observed. Therefore, plasma mannose levels obtained via glucose tolerance testing may be used as a new diagnostic method for evaluating insulin resistance or deficiency in diabetic dogs.     

Prostate cancer in dogs: comparative and clinical aspects

The canine prostate gland shares many morphological and functional similarities with the human prostate and dogs are the only other large mammals that commonly develop spontaneous prostate cancer. However, the incidence of prostate cancer is much lower in dogs and the precise cell of origin is not known. Dogs with prostate cancer usually present with advanced disease that does not respond to androgen deprivation therapy. Similar to humans, affected dogs often develop osteoblastic bone metastases in the pelvis and/or lumbar spine with associated pain and neurological deficits. Other clinical signs include weight loss, lethargy, and abnormal urination and/or defecation. Surgery, chemotherapy, and radiation have been used to treat dogs with prostate cancer, but success has been limited by the location and aggressive nature of the disease. It is evident that better methods of early detection and more effective therapies are needed for prostate cancer in dogs and advanced prostate carcinoma in men. Dogs with naturally-occurring prostate cancer are relevant models for the disease in humans and pre-clinical studies of new diagnostics and therapies in dogs may benefit both humans and dogs with prostate cancer.     

Genetic variants of the unsaturated fatty acid receptor GPR120 relating to obesity in dogs

G protein-coupled receptor (GPR) 120 is an unsaturated fatty acid receptor, which is associated with various physiological functions. It is reported that the genetic variant of GPR120, p.Arg270His, is detected more in obese people, and this genetic variation functionally relates to obesity in humans. Obesity is a common nutritional disorder also in dogs, but the genetic factors have not ever been identified in dogs. In this study, we investigated the molecular structure of canine GPR120 and searched for candidate genetic variants which may relate to obesity in dogs. Canine GPR120 was highly homologous to those of other species, and seven transmembrane domains and two N-glycosylation sites were conserved. GPR120 mRNA was expressed in lung, jejunum, ileum, colon, hypothalamus, hippocampus, spinal cord, bone marrow, dermis and white adipose tissues in dogs, as those in mice and humans. Genetic variants of GPR120 were explored in client-owned 141 dogs, resulting in that 5 synonymous and 4 non-synonymous variants were found. The variant c.595C>A (p.Pro199Thr) was found in 40 dogs, and the gene frequency was significantly higher in dogs with higher body condition scores, i.e. 0.320 in BCS4–5 dogs, 0.175 in BCS3 dogs and 0.000 in BCS2 dogs. We conclude that c.595C>A (p.Pro199Thr) is a candidate variant relating to obesity, which may be helpful for nutritional management of dogs.     

PCR-based coprodiagnostic tools reveal dogs as reservoirs of zoonotic ancylostomiasis caused by Ancylostoma ceylanicum in temple communities in Bangkok

A survey of gastrointestinal parasites of dogs and humans from temple communities in Bangkok revealed that 58% of dogs and 3.4% of humans, among those sampled, were infected with hookworms utilising faecal flotation techniques and microscopy. A previously established polymerase chain reaction (PCR)-RFLP approach was utilised to determine the species of hookworms infecting dogs found positive for hookworm eggs. Single infections with Ancylostoma ceylanicum and Ancylostoma caninum were recorded in 77% and 9% of hookworm positive dogs, respectively and mixed infections with both species of Ancylostoma were recorded in 14% of dogs. A single-step PCR for the multiplex detection of Ancylostoma species and Necator americanus DNA in human faeces was developed and applied to characterise the species of hookworms in microscopy positive individuals. Single infection with N. americanus was recorded in five and A.ceylanicum infection in two, out of seven individuals positive for hookworm. This study demonstrates that humans are at risk of acquiring infection with A. ceylanicum in communities where this species of hookworm is endemic in dogs.