Experimental canine leptospirosis caused by Leptospira interrogans serovars pomona and bratislava

OBJECTIVE: To evaluate gross, histopathologic, and serum biochemical findings caused by Leptospira interrogans serovars pomona and bratislava inoculated in dogs. ANIMALS: Twenty-seven 8-week-old female Beagles. PROCEDURE: Dogs were randomly assigned to challenge or control groups. Challenge groups were conjunctivally inoculated on 3 successive days with 5 x 10(7) L interrogans serovar pomona (n = 12) or serovar bratislava (11). Clinical signs were recorded throughout the experiment, and clinical pathology assays, bacteriologic culture, and necropsies (6 or 7 dogs necropsied at each time point) were done on postinoculation day (PID) 7, 10, 14, and 20. RESULTS: Infection could not be confirmed in any serovar bratislava-inoculated dog, and control dogs remained healthy throughout the experiment. Positive culture and fluorescent antibody test results were confirmed in 11 of 12 serovar pomona-inoculated dogs. Fever and lethargy starting at PID 7 were the most common clinical signs in serovar pomona-infected dogs. On day 10, gross lesions included multifocal renal and pulmonary hemorrhage and perirenal edema. Serovar pomona-inoculated dogs had histopathologic lesions including hepatitis, interstitial nephritis, and pneumonia at PID 7, 10, 14, and 20. Increases in BUN, anion gap, and bilirubin concentration occurred on PID 10, 14, and 20. Platelet counts in dogs with positive results of bacteriologic culture were decreased from baseline values on PID 10, 12, and 14. CONCLUSIONS AND CLINICAL RELEVANCE: Conjunctival inoculation with L interrogans serovar pomona resulted in a high rate of infection with concomitant hemorrhagic and inflammatory lesions of the kidneys, liver, and lungs.     

Seroepidemiology of leptospirosis in livestock in Trinidad

A study was conducted to determine the seroprevalence of leptospirosis and infecting serovars across livestock (cattle, sheep, goats, and pigs) in Trinidad using the microscopic agglutination test with an international panel of 23 serovars. Of a total of 590 cattle tested, 21.5% were seropositive with agglutinations to 13 of the 23 antigens used in the panel. Icterohaemorrhagiae (9.3%), Sejroe (4.1%), Ballum (4.1%), and Autumnalis (1.9%) were the predominant serogroups detected in the cattle sampled (n = 590). Of 222 sheep tested, 5.0% were seropositive with agglutinations to five serovars belonging to two serogroups. These serogroups were Autumnalis at 2.7%, and Icterohaemorrhagiae at 2.3% of all sheep tested (n = 222). Of a total of 180 goats tested, 3.3% were seropositive, all agglutinating to the Icterohaemorrhagiae serogroup, 1.7% to serovar Copenhageni, 1.1% to serovar Mankarso, and 0.6% to serovar Icterohaemorrhagiae. Among pigs (n = 200), 5.0% were seropositive for five serovars belonging to three serogroups. These serogroups were Icterohaemorrhagiae at 2.5%, Australis at 2%, and Ballum at 0.5%. Overall, age and sex of animals were not significantly associated with leptospirosis with the exception of cattle where age was a significant factor for seropositivity. It was concluded that for livestock, leptospirosis may be an important zoonotic and economic disease, particularly in the case of cattle. It is imperative that the impact of leptospirosis on abortion, stillbirths, and decreased milk production in livestock in the country be assessed.     

一例犬钩端螺旋体感染的诊疗

云南某犬场饲养的犬发生一例犬钩端螺旋体感染病例,临床表现高热、血尿、赫氏反应等典型临床症状,尿液细菌学检查结果确诊为钩端螺旋体感染,血清学追溯检查表明感染病原为大型犬群钩端螺旋体。现将诊断及治疗结果报道如下。     

Three cases of canine leptospirosis in Quebec

Three dogs from different locations with acute renal failure were hospitalized in autumn 1996 and 1997. Leptospira interrogans serovar pomona was detected by the microscopic agglutination test. All dogs recovered after antibiotic treatment. The importance of the development of vaccines adapted to emerging serovars in dogs should be addressed.     

SARS-CoV-2 in animals: potential for unknown reservoir hosts and public health implications

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, previously 2019-nCoV) is suspected of having originated in 2019 in China from a coronavirus infected bat of the genus Rhinolophus. Following the initial emergence, possibly facilitated by a mammalian bridge host, SARS-CoV-2 is currently transmitted across the globe via efficient human-to-human transmission. Results obtained from experimental studies indicate that animal species such as cats, ferrets, raccoon dogs, cynomolgus macaques, rhesus macaques, white-tailed deer, rabbits, Egyptian fruit bats, and Syrian hamsters are susceptible to SARS-CoV-2 infection, and that cat-to-cat and ferret-to-ferret transmission can take place via contact and air. However, natural infections of SARS-CoV-2 have been reported only in pet dogs and cats, tigers, lions, snow leopards, pumas, and gorillas at zoos, and farmed mink and ferrets. Even though human-to-animal spillover has been reported at several instances, SARS-CoV-2 transmission from animals-to-humans has only been reported from mink-to-humans in mink farms. Following the rapid transmission of SARS-CoV-2 within the mink population, a new mink-associated SARS-CoV-2 variant emerged that was identified in both humans and mink. The increasing reports of SARS-CoV-2 in carnivores indicate the higher susceptibility of animal species belonging to this order. The sporadic reports of SARS-CoV-2 infection in domestic and wild animal species require further investigation to determine if SARS-CoV-2 or related Betacoronaviruses can get established in kept, feral or wild animal populations, which may eventually act as viral reservoirs. This review analyzes the current evidence of SARS-CoV-2 natural infection in domestic and wild animal species and their possible implications on public health.     

Modulation of immune response through nutraceutical interventions: implications for canine and feline health.

Mounting research demonstrates that certain nutraceutical compounds interact with the immune system. These interactions may be positive or negative depending on the compound or dose administered to the individual. Understanding the mechanisms by which these compounds work should provide opportunities to design nutritional interventions to bolster the health of dogs and cats.     

南京地区30例犬钩端螺旋体病的调查研究

对南京地区30例钩端螺旋体病犬的基本信息进行收集,并对易感动物、传播途径、发病日期、发病症状进行了统计分析,旨在描述目前南京地区犬钩端螺旋体病的流行情况。数据来源主要是南京地区的宠物医院,确诊手段选择PCR诊断方法,并对诊断方法进行了详细描述。研究发现,未去势青壮年和未进行钩端螺旋体免疫的公犬是高发群体;病初主要表现出呕吐、脱水精神差、结膜潮红等症状;在南京地区雨水较多的月份发病率高于雨水少的月份;由于南京地区泰迪犬的保有量相对其他品种要高,故钩端螺旋体病患犬中,泰迪犬占了50%。     

Clinical and epidemiological features of canine leptospirosis in North Queensland

OBJECTIVE: To evaluate the clinical signs, results of clinical pathology and serology tests, and treatment outcome of clinical leptospirosis in 40 dogs from North Queensland. DESIGN: Retrospective study from January 1995 to August 1999. PROCEDURE: Case records were reviewed for age, breed, sex, month of submission, geographical location and presenting clinical signs in 40 dogs with titres of > or = 200 for leptospirosis by the microscopic agglutination test. A biochemistry panel and complete blood count were performed on 18 dogs. RESULTS: Canine leptospirosis occurred most frequently during the summer and autumn particularly in the 'wet' tropical coastal areas of Mackay and Cairns. Fewer cases were seen in the Atherton Tablelands and 'dry' tropics around Townsville. Young and male dogs were more commonly affected. Most cases were caused by L australis (80%) and L zanoni (15%) with individual cases of L hardjo and L copenhageni. All dogs showed a distinctive multiorgan disease pattern including renal failure and cholestatic hepatopathy. Presenting clinical signs were related to these disease syndromes and included jaundice, vomiting, lethargy, inappetence, dehydration, pyrexia, abdominal pain and diarrhoea. Just over 50% of the dogs in the present study failed to recover. Clinical biochemical changes indicative of renal failure and cholestasis were significantly less severe in dogs that recovered compared with dogs that did not survive. CONCLUSIONS: Clinical pathology testing should be performed on all dogs presented for illness in the endemic areas so as to help make a presumptive diagnosis and assist in determining the prognosis as soon as possible. The presumptive diagnosis should be confirmed serologically.     

Survey of veterinarians' recommendations for treatment and control of intestinal parasites in dogs: public health implications

A systematic, random sample of 450 small and mixed-animal practitioners was selected from the client list of a prominent veterinary pharmaceutical and animal health company. A telephone survey was conducted, using a standard questionnaire, to assess whether current veterinary practices concerning prophylaxis and treatment of canine roundworm (Toxocara canis) and hookworm (Ancylostoma spp) infections are adequate to prevent transmission to human beings. Analysis of results focused on 3 questions related to prevention: practitioner's frequency of client education regarding zoonotic potential of roundworms and hookworms, pup age at which veterinarian recommends first anthelmintic treatments, and proportion of veterinarians recommending prophylactic drug administration for pups and nursing bitches. Despite the proven association of household pet dogs and human toxocariasis, only a third (148/450) of veterinarian respondents routinely discussed the potential zoonotic hazards of canine roundworms with their clients. A total of 29% (130/450) of veterinarians surveyed either never discussed these potential hazards or discussed them only when asked by their clients. With regard to anthelmintic treatment practices, 31% (140/450) of veterinarians surveyed recommended that pups first be examined and treated for intestinal parasites within 4 weeks of age. Thirty-three percent (163/450) recommended first examination and deworming at 5 to 6 weeks of age, and 36% (163/450) suggested that it be done at or after 7 weeks of age. Less than half (208/450) of veterinarians administered anthelmintics prophylactically to at least some pups and dogs. Sixty-four percent (287/450) of respondents recommended routine testing and treatment of nursing bitches.(ABSTRACT TRUNCATED AT 250 WORDS)     

Epidemiology of dog bites: a Belgian experience of canine behaviour and public health concerns

This paper reviews three studies that have been conducted in Belgium on dog bites on children. (1) A telephone study revealed that 22/1000 children <15 years of age were victims of dog bites annually. (2) Data on the characteristics of dog bites were collected prospectively over a period of 8.5 months in six hospital emergency departments. "Dangerous dogs" were not responsible for the majority of the accidents. In 67/100, incidents documented, the bites appeared to be triggered by an interaction of the child. Education appeared to be the preventive measure with the highest priority. (3) Among 22 child victims of dog bites, 12 had symptoms of post-traumatic stress disorders some seven months following the accident. Based on these local studies, several initiatives have been undertaken to favour both primary and secondary prevention measures. An appropriate psychological preventive intervention should be offered to all victims of dog bites.     

Prevention of renal carriage of leptospirosis in dogs by vaccination

Dogs vaccinated with a Leptospira interrogans vaccine containing serogroups Canicola and Icterohaemorrhagiae and prepared from cultures grown in a protein-free medium resisted challenge with heterologous representatives of these serogroups. In contrast, control dogs were pyrexic and leptospires were isolated from the blood for nine days following Canicola challenge and six days after Icterohaemorrhagiae challenge. Leptospires were isolated from the urine of controls throughout the post challenge period and from kidneys at post mortem examination of six out of six and four out of six Canicola and Icterohaemorrhagiae challenged controls, respectively. There have been no reports of hypersensitivity reactions to this vaccine since its introduction in 1980.     

Three-year duration of immunity in dogs following vaccination against canine adenovirus type-1, canine parvovirus, and canine distemper virus

A challenge-of-immunity study was conducted to demonstrate immunity in dogs 3 years after their second vaccination with a new multivalent, modified-live vaccine containing canine adenovirus type 2 (CAV-2), canine parvovirus (CPV), and canine distemper virus (CDV). Twenty-three seronegative pups were vaccinated at 7 and 11 weeks of age. Eighteen seronegative pups, randomized into groups of six dogs, served as challenge controls. Dogs were kept in strict isolation for 3 years following the vaccination and then challenged sequentially with virulent canine adenovirus type 1 (CAV-1), CPV, and CDV. For each viral challenge, a separate group of six control dogs was also challenged. Clinical signs of CAV-1, CPV, and CDV infections were prevented in 100% of vaccinated dogs, demonstrating that the multivalent, modified-live test vaccine provided protection against virulent CAV-1, CPV, and CDV challenge in dogs 7 weeks of age or older for a minimum of 3 years following second vaccination.