In vivo prostate cancer research: Key interspecies prostate anatomical features for translation medicine

Prostate cancer (PCa) is a prevalent malignancy affecting men worldwide. Animal models play a crucial role in studying PCa pathology and discovering novel approaches to prevent, detect and treat this disease. However, the challenge of translational medicine is the limited reproducibility and inadequate recapitulation of human conditions in animal models. Therefore, a comprehensive understanding of the macroscopic and microscopic anatomy of the prostate gland among distinct animal species is essential for better translating research findings to clinical practice. This review aims to compare and describe the macroscopic and microscopic anatomy of the prostate gland in humans, rats, and dogs, emphasizing the relevant features. Despite the anatomical differences between these species, rats are a valuable model to study human prostate diseases, once they share some features implicated in carcinogenesis in humans. Dogs, on the other hand, are considered the best model for studying PCa due to the development of spontaneous cancer with a higher incidence when compared with other animals and the development of bone metastases. Moreover, the lymphatic system and the sentinel lymph node role and mapping are similar in dogs and humans. However, it is important to recognize that no animal model can directly mimic all aspects of PCa as the human prostate is anatomically different from that of rats and dogs. Therefore, it is essential to analyze and understand the intra- and interspecies variability when translating research findings into clinical practice. This review highlights the importance of a thorough understanding of the anatomical differences between the prostate gland in humans, rats, and dogs when selecting the appropriate animal model for studying PCa.

The seroprevalence of canine dirofilariosis in dogs in the eastern coastal areas of China

Background and objectives

The present study was carried out to assess the presence of canine Dirofilaria immitis infection in pet dogs in China.

Materials and methods

From October 2018 to November 2019, a total of 216 sera were collected from pet hospitals in Shandong, Jiangsu, Shanghai, Zhejiang, and Fujian regions of Eastern China. The sera were tested by using a commercial canine heartworm antibody ELISA test kit.

Results

70.8% of the pets had significant clinical symptoms resembled to heartworm infection; the overall dirofilariosis positivity found was 12.5% (27/216); Significant positive rates differences were observed between symptomatic and asymptomatic dogs (P < 0.05) (i.e. 15.7% and 4.7% respectively).The prevalence of infection in Shandong Province (15.5%) was the highest among the surveyed areas, but the difference among the geographic regions was not statistically significant (P > 0.05). Furthermore, the prevalence detected in summer (28.2%) was significantly higher than in other seasons (P < 0.05). In addition, no significant difference was observed between male and female sex (P > 0.05).

Conclusions

Altogether, these results suggest that an epidemic of dirofilariosis exists in eastern coastal China, as such preventive measures should be taken to control the spread of dirofilariosis to reduce the risk of human and pet infection with heartworm.

Development of acute pancreatitis after oral administering a praziquantel, pyrantel pamoate, and febantel combination in a dog: A case report

Oral praziquantel, pyrantel pamoate, and febantel combination (PPFC) is a highly safe anthelmintic treatment commonly administered for the purpose of canine gastrointestinal parasites with mild adverse effects such as anorexia, vomiting, lethargy, or diarrhea. A 12-year-old castrated Chihuahua was brought to our hospital for a periodic health examination. Although his general physical examination showed no abnormalities, blood test results showed increase in the liver enzyme, lipase activity, total bile acid, total cholesterol, and triglyceride concentration. Moreover, the dog had underlying tricuspid regurgitation that was not treated. PPFC was prescribed on the suspicion of gastrointestinal tract parasites. Following the oral administration of PPFC at home, anorexia and lethargy were found, and vomiting and diarrhea were noted after 30 h. The dog was diagnosed with acute pancreatitis based on clinical course of the disease and subsequent pathology results. Although intravenous drip was initiated upon hospitalization, the treatment was discontinued owing to financial reasons. The onset of acute pancreatitis can be considered an adverse effect of PPFC. Although the association between PPFC administration and the onset of acute pancreatitis could not be clarified in this case, the onset of acute pancreatitis may have been associated with a decrease in liver function and/or increase in the false activity of lipase. PPFC has been considered highly safe in dogs, although care should be taken when administering medications to dogs suspected of having an underlying disorder.

Factors associated with Giardia infection in dogs in southern Ontario, Canada

Information concerning risk factors associated with Giardia infection in dogs in southern Ontario, Canada, is currently lacking. This study therefore aimed to identify risk factors for Giardia infection in dogs that visit off-leash dog parks in southern Ontario. From May-November 2018, fecal samples were collected from 466 dogs in 12 off-leash dog parks in the Niagara and Hamilton regions of Ontario. A survey that asked questions pertaining to travel history (i.e., area of residence, locations and regions visited in the previous 6 months), basic medical history (i.e., spay/neuter status, veterinary visits, use of deworming medication), consumption of a raw diet, and the physical (i.e., age, sex, breed) and behavioral characteristics (i.e., off-leash activities, hunting activities) of each dog sampled was administered to the respective owner. All fecal samples were examined with the Giardia plate ELISA (IDEXX Laboratories) for parasite antigen. Multivariable logistic regression analyses were conducted on the survey data to investigate putative risk factors for Giardia infection. Overall, 11.8% (95% CI: 9.2-15.1%) of samples tested positive for Giardia antigen. Results from the multivariable logistic regression analyses identified an interaction between dog age and spay/neuter status that was significantly associated with Giardia infection. The odds of infection were greater in intact as compared to neutered adult dogs (OR: 3.6, 95% CI: 1.7-7.9, p = 0.001), and in neutered juvenile dogs as compared to neutered adults (OR: 5.2, 95% CI: 2.2-12.2, p < 0.001). The results provide veterinarians with evidence-based information for identifying dogs at greatest risk of Giardia infection in southern Ontario.

Efficacy and adverse events of anthracycline and propranolol combination in five dogs with stage 3 hemangiosarcoma

Background

Canine hemangiosarcoma (HSA), which originates from endothelial cells, is one of the most common malignant neoplasms that frequently develop metastatic lesions. Although anthracycline-based HSA treatment strategies have been widely investigated, reliable therapy for dogs with clinically advanced-stage HSA (stage 3 HSA) has not been established yet. Recently, several studies have demonstrated that propranolol, a beta-adrenergic receptor antagonist, exhibits anti-tumor effects against tumors originating from vascular endothelial cells, indicating the possibility that propranolol is a candidate adjunctive agent for anthracycline-based therapy in dogs with stage 3 HSA. This study aimed to evaluate the clinical efficacy and adverse events (AEs) of anthracycline and propranolol combination in stage 3 HSA-affected dogs.

Case Description

We retrospectively investigated five dogs diagnosed with stage 3 HSA which were administered with both anthracycline and propranolol during the same period between January 2020 and August 2021. Clinical benefit was observed in four of five HSA dogs (one of complete response, one of partial response, and two of stable disease) with gross metastatic lesions by anthracycline and propranolol combination. Notably, some or all of the metastatic lesions were reduced in two cases. In all five dogs administered with anthracycline and propranolol combination, no serious and irreversible AEs were observed.

Conclusion

Our findings demonstrate the efficacy and safety of anthracycline and propranolol combination in stage 3 HSA-affected dogs. Further studies are needed to establish treatment protocols based on anthracycline and propranolol combination for dogs with advanced HSA.

Thirty years of telemetry-based data acquisition for cardiovascular drug safety evaluation: Applications and optimization

Conducting safety evaluations of new drugs using conscious animals has been a specialty of our working group for thirty years. In this article, we review the various technical challenges and solutions dealt with over the years to improve both the data quality and the well being of our animal subjects. Of particular interest for us has been the use of telemetry-based data acquisition for conducting studies on cardiovascular (CV) function. This includes the evolving technical aspects of the studies, as well as the development of new applications that take advantage of this technical approach.

Heritability and Genetic Trend of Body Weight in Dogs of Different Breeds in Sweden

High body weight (BW) in dogs has been associated with developmental as well as degenerative diseases, but the heritability of BW in dog breeds is largely unknown. The aim of the current study was to estimate heritability and genetic change (genetic trend) for BW in a range of dog breeds in Sweden. Body weight registrations from 19 dog breeds (with n ranging from 412 to 4710) of varying body size, type and usage were collected from 2007 to 2016. The average BW of the breeds was 8-56 kg. The BW registrations were performed when the dogs were 12-24 months of age (18-30 months for one large-sized breed) in connection with an official radiographic screening program for hip dysplasia. Collected weight records were used to estimate heritability and genetic trends for BW. Several statistical models were used. The preliminary model included the fixed effects of breed (p<0.001), sex (p<0.001), year of screening (p<0.001), litter size (p=0.06), parity of the dam (p=0.03) and linear regression on age at screening (p<0.001), the latter five effects all nested within breed, and the random effects of litter and dam. Season of birth and the quadratic effect of age were also tested, but were not significant (p>0.10). For the genetic analysis, various mixed linear models were tested within breed with different combinations of random effects; the most complex model included random effects of litter, direct additive and maternal genetic effects, and maternal permanent environmental effect. The average heritability for BW over all 19 breeds was 51%, with a range of 35-70%, and the additive genetic coefficient of variance was around 9%. Maternal heritability was 5-9% and litter variance was below 10% with one exception (15% in Shetland Sheepdogs). For nine breeds, there was a genetic trend of increasing BW, whereas seven breeds had a genetic trend of decreasing BW. The largest absolute genetic change over a 10-year period was around 0.6 kg or about 2% of the mean. In conclusion, given the small genetic changes in spite of the high heritability, it seems that there is generally a very weak selection, if any, for BW in the included dog breeds.

MiR-150 regulates the Leishmania infantum parasitic load and granzyme B levels in peripheral blood mononuclear cells of dogs with canine visceral leishmaniosis

Leishmania infantum causes visceral leishmaniosis, a neglected tropical disease that can modulate the host immune response by altering the expression of small non-coding RNAs called microRNAs (miRNAs). Some miRNAs are differentially expressed in peripheral blood mononuclear cells (PBMCs) of dogs with canine visceral leishmaniosis (CanL), like the down-regulated miR-150. Even though miR-150 is negatively correlated with L. infantum parasitic load, it is unclear if miR-150 directly affects L. infantum parasitic load and (if so) how this miRNA would contribute to infection. Here, we isolated PBMCs from 14 naturally infected dogs (CanL group) and six healthy dogs (Control group) and treated them in vitro with miR-150 mimic or inhibitor. We measured L. infantum parasitic load using qPCR and compared treatments. We also measured miR-150 in silico predicted target protein levels (STAT1, TNF-α, HDAC8, and GZMB) using flow cytometry or enzyme-linked immunosorbent assays. Increasing miR-150 activity diminished L. infantum parasitic load in CanL PBMCs. We also found that inhibition of miR-150 reduced GZMB (granzyme B) levels. These findings demonstrate that miR-150 plays an important role in L. infantum infection in canine PBMCs, and they merit further studies aiming at drug development.

Treatment of spontaneous canine mast cell tumors by electrochemotherapy combined with IL-12 gene electrotransfer: Comparison of intratumoral and peritumoral application of IL-12

The combined treatment of electrochemotherapy (ECT) and interleukin-12 (IL-12) gene electrotransfer (GET) has already been used in clinical studies in dogs to treat various histological types of spontaneous tumors. The results of these studies show that the treatment is safe and effective. However, in these clinical studies, the routes of administration of IL-12 GET were either intratumoral (i.t.) or peritumoral (peri.t.). Therefore, the objective of this clinical trial was to compare the two IL-12 GET routes of administration in combination with ECT and their contribution to the enhanced ECT response. Seventy-seven dogs with spontaneous mast cell tumors (MCTs) were divided into three groups: one treated with a combination of ECT + GET peri. t. (29 dogs), the second with the combination of ECT + GET i.t. (30 dogs), and the third with ECT alone (18 dogs). In addition, immunohistochemical studies of tumor samples before treatment and flow cytometry of peripheral blood mononuclear cells (PBMCs) before and after treatment were performed to determine any immunological aspects of the treatment. The results showed that local tumor control was significantly better in the ECT + GET i.t. group (p < 0.050) than in the ECT + GET peri.t. or ECT groups. In addition, disease-free interval (DFI) and progression-free survival (PFS) were significantly longer in the ECT + GET i.t. group than in the other two groups (p < 0.050). The data on local tumor response, DFI, and PFS were consistent with immunological tests, as we detected an increased percentage of antitumor immune cells in the blood after treatment in the ECT + GET i.t. group, which also indicated the induction of a systemic immune response. In addition, we did not observe any unwanted severe or long-lasting side effects. Finally, due to the more pronounced local response after ECT + GET i.t., we suggest that treatment response assessment should be performed at least two months after treatment, which meets the iRECIST criteria.

Demography and disorders of English Cocker Spaniels under primary veterinary care in the UK

BACKGROUND

The English Cocker Spaniel (ECS) is a common family dog in the UK. This study aimed to describe demography, morbidity, and mortality in ECS under primary veterinary care in the UK during 2016 using data from the VetCompass™ Programme. This study hypothesised that the prevalence of aggression is higher in male than female ECS, and higher in solid-coloured than bi-coloured ECS.

RESULTS

English Cocker Spaniels comprised 10,313/336,865 (3.06%) of dogs under primary veterinary care during 2016. The median age was 4.57 years (inter-quartile range (IQR) 2.25-8.01) and the median adult bodyweight was 15.05 kg (IQR 13.12-17.35). The annual proportional birth rate was relatively stable between 2.97-3.51% from 2005-2016. The most common specific diagnoses were periodontal disease (n = 486, prevalence 20.97%, 95% confidence interval (CI): 19.31-22.62), otitis externa (n = 234, 10.09%, 95% CI: 8.87-11.32), obesity (n = 229, 9.88%, 95% CI: 8.66-11.09), anal sac impaction (n = 187, 8.07%, 95% CI: 6.96-9.18), diarrhoea (n = 113, 4.87%, 95% CI: 4.00-5.75), and aggression (n = 93, 4.01%, 95% CI: 3.21-4.81). The prevalence of aggression was higher in males (4.95%) than in females (2.87%) (P = 0.015) and in solid-coloured (7.00%) than in bi-coloured dogs (3.66%) (P = 0.010). The median age at death was 11.44 years (IQR 9.46-13.47) and the most common grouped causes of death were neoplasia (n = 10, 9.26%, 95% CI: 3.79-14.73), mass-associated disorders (n = 9, 8.33%, 95% CI: 4.45-15.08), and collapse (n = 8, 7.41%, 95% CI: 3.80-13.94).

CONCLUSIONS

Periodontal disease, otitis externa, and obesity are identified as the most common health issues for ECS, and neoplasia and mass-associated disorders as the most common reasons for death. The prevalence of aggression was higher in males and solid-coloured dogs. The results can aid veterinarians in giving evidence-based health and breed choice information to dog owners and highlights the importance of thorough oral examination and body condition score evaluation during routine veterinary examination of ECS.

TLRs expression in canine mammary gland neoplasms: a pathological and molecular study

TLRs are a class of PRRs that play a vital role in innate immunity. TLRs are expressed on immune cells and mammary epithelial cells. They can promote tumor growth, angiogenesis, invasion, and viability signaling. The current study aimed to test the correlation between histologic types and grades of neoplasms and TLRs gene expression levels. Twenty-one tissue samples of canine mammary neoplasms were stained with H&E. Then, it evaluated histologic type and grade according to the methods of Goldschmidt et al. and Peña, respectively. We established real-time PCR quantification assays to measure the mRNA abundances of TLRs in normal and neoplastic mammary glands. Profile pattern of TLR 1, 2, 3, 4, 5, 6, and 9 genes expression in canine mammary glands performed in 21 samples of mammary gland neoplasms and three non-neoplastic mammary gland samples from normal dogs. TLR 3, 4, and 9 mRNA overexpression were detected. In addition, tubulopapillary carcinoma grade II, SCC grade III, and carcinoma mixed type grade II demonstrated the highest relative TLR-3, and 9 mRNA expression levels. Complex carcinoma grade I, ductal carcinoma grade II, and anaplastic carcinoma grade II showed the highest relative TLR4 mRNA expression level. Although histopathological characteristics of tumors, including histologic type, grade, and inflammation, influenced TLRs mRNA expression level, such correlation was insignificant (P > 0.05).

Dimethyl sulfoxide favors the emetic efficacy of lycorine in beagle dogs - a novel strategy for the treatment of poisoning

Poisoning in small animals represents an ongoing hazard and therapeutic problem in veterinary medicine. Therapeutic induction of emesis in time enables a fast elimination of a toxic compound resulting in a shortened course of poisoning and a higher safety level thereafter, which decisively improves prognosis and treatment. Lycorine is a reliable emetic drug in beagle dogs without serious side effects thought to be more beneficial in tolerability and efficacy than the rarely used apomorphine. Therefore, this study investigates efficacy and tolerability of differently composed potential drug formulations of lycorine hydrochloride for s.c. administration in dogs as an emetic principle. By emesis response analysis four dimethyl sulfoxide (DMSO)-based active pharmaceutical ingredient (API) formulations were favored. Two of them (F5 and F6) qualified for further drug development. Both formulations ensure a safe pharmacologically induced emesis within about 30 min after injection, suitable for use as an in time decontaminant in acute poisoning of dogs. DMSO-based formulations were well tolerated and offer a novel promising strategy for treatment of poisoning.

Dogs showed lower parasympathetic activity during mutual gazing while owners did not

The affiliative relationship between humans and dogs is compared to a mother-infant attachment relationship. We hypothesized that dog's attachment behavior in negative emotional state aroused the owner's attention toward the dog, that is, reduced parasympathetic activity. We measured heart rate variability in both dogs and humans during the Strange Situation Test to examine whether the owners' parasympathetic activity was decreased by being gazed at by their dogs. Our results in a short-term of 6 s before and after the moment the dog gazed at the human face indicated that dogs' parasympathetic activity was lower when the dogs were gazing at their owners than when it was gazing at unfamiliar persons. Dog's autonomic activity was also lower when the dogs were living with their owners for a longer period. However, we could not determine whether gaze from the dog affected the autonomic activity in humans as attachment behavior.

Meowing dogs: can dogs recognize cats in a cross-modal violation of expectancy task (Canis familiaris)?

Dogs can recognize conspecifics in cross-modal audio-video presentations. In this paper, we aimed at exploring if such capability extends to the recognition of cats, and whether it is influenced by exposure to these animals. To reach our aim, we enrolled 64 pet dogs. Half of the dogs were currently living with cats, while the rest had never been living with cats, nor were at the time of the experiment. All dogs underwent a cross-modal violation of expectancy experiment, where they were presented with either a cat or a dog vocalization, followed by a video of either species on a blank background. The result revealed that dogs did not exhibit a surprise reaction towards the incoherent stimuli of a cat vocalization and a dog video or vice-versa, implying that they had not recognized the stimuli portraying cats. The pattern of results did not differ between dogs living or not with cats, implying that exposure to a limited number of cats, however, prolonged, is not sufficient to grant dogs with the ability to recognize them on audio-video presentations. We propose that the lack of recognition could be due to the small number of individual cats the dogs are regularly exposed to, or to the possible lack of early exposure to cats during the socialization phase.

Embryonic resorption rates at canine pregnancy diagnoses: A retrospective evaluation

Pregnancy diagnosis in canines is generally performed during embryonic phase, between 19 and 35 days of gestation. At this stage embryonic resorptions can be observed, which, according to the literature, affects 11-26% of conceptuses and 5-43% of pregnancies. Resorption has been hypothesized as a physiological event in uterine overcrowding, however other factors may be involved, such as infectious or non-infectious diseases. This study aimed to retrospectively evaluate the incidence of embryo resorption at ultrasonographic pregnancy diagnosis in different dog breeds, and to identify the main factors determining the occurrence of the resorption sites. 95 pregnancy diagnoses were performed 21-30 days post-ovulation by ultrasound examination on 74 different animals. Breed, weight, and age of the bitches were recorded, and the reproductive anamnesis was collected from their medical records. The overall pregnancy rate was 91.6%. In 48.3% of pregnancies (42/87), at least one resorption site was visible, and embryonic resorption rate was 14.2% (61 resorption sites/431 total structures). Binary logistic regression showed a significant effect of age (P < 0.001), but not the size of the litter (P = 0.357), nor the size of the mother (P = 0.281) or any previous reproductive problems (P = 0.077). Age was significantly higher in pregnancies with resorptions than in normal ones (60.88 ± 18.24 and 40.27 ± 15.74 months, respectively, P < 0.001). The embryonic resorption rate was in line with previous findings, while the incidence of affected pregnancies was higher. Although resorptions may occur physiologically in pregnancies with large litters, a relationship between embryo resorption and litter size was not identified in our sample group, while aging increased the resorption rates. This, together with the occurrence of repeated embryonic resorptions in some bitches included in the study, suggests how resorptions could also be the result of pathological events. The underlying mechanisms and other factors that may be involved need further clarification.

A review of 95 pit viper envenomations in Northcentral Florida (2018-2020)

The medical records of 95 pit viper envenomations in client-owned dogs presented to an academic emergency hospital in the Southeastern United States during the period spanning 2018 and 2020 were retrospectively examined. This study's primary objectives were to record the clinical abnormalities and treatment responses associated with envenomation and their relation to outcome. Approximately 80% of the bites involved the head region associated with varying degrees of hemorrhagic lymphedema. Some of the most common additional symptoms observed were; hypotension (10%), cardiac dysrhythmias (17%), and coagulopathy (21%). Treatment in most cases consisted of intravenous fluids, antivenom, and analgesic drugs. Blood products were used as indicated for anemia and persistent bleeding. The average dose of the F('ab')₂ was 1-2 vials. Additional vials (3-22) were administered as needed to counteract persistent or recurrent coagulopathy and hemolysis. Only 3% of the dogs had mild clinical signs of Type 1 hypersensitivity during their treatment period. Antihistamine use at the tertiary hospital was restricted to the three dogs showing signs of a suspected allergic reaction in response to antivenom administration; these patients received diphenhydramine intramuscularly. A glucocorticoid drug was used in only one dog prior to referral but not subsequently. Ninety dogs had a good outcome, while five died. Historically, pit viper envenomation in dogs in the southeastern United States has been a potentially life-threatening problem. Most dogs will survive if treated promptly and appropriately with adequate amounts of intravenous fluids, and antivenom titrated on severity of clinical presentation.

Resolution of congestive heart failure and reverse remodeling in two Chihuahuas with flail mitral valve leaflets

Development of a flail mitral valve (MV) leaflet secondary to ruptured chordae tendineae in the setting of myxomatous mitral valve disease is a known complication of the disease that often results in severe mitral regurgitation. Two cases are presented in which a flail anterior MV leaflet caused severe mitral regurgitation and led to the development of congestive heart failure in male castrated Chihuahuas. Over variable periods of time, repeat cardiac evaluation disclosed reverse left-sided cardiac remodeling and lessened mitral regurgitation that allowed for withdrawal of furosemide in both dogs. While rare, improvement in mitral regurgitation severity may occur without surgical intervention, allowing for reverse left-sided cardiac remodeling and discontinuation of furosemide.

The impact of environmental and biological factors on the resting heart rate of dogs as assessed using 20 years of data from safety pharmacology studies

INTRODUCTION

A safety pharmacology study detects and evaluates potential side effects of a new drug on physiological function at therapeutic levels and above and, in most cases, prior to the initiation of clinical trials. The aim of this study was to investigate the effects of environmental and biological factors on resting heart rate (HR), a representative cardiac parameter in cardiovascular safety pharmacology.

METHODS

Over twenty years, 143 dogs (Beagles, Labradors and mongrels) received implanted telemetry transmitters to measure aortic pressure (AP), left ventricular pressure (LVP), Electrocardiogram (ECG) and body temperature. Throughout the 7-h period of data collection, data were continuously recorded without drug treatment and included the range of HRs resulting from spontaneous physiological changes. Statistics and visualizations were calculated using R and Spotfire.

RESULTS

Beagles had a higher HR than the mongrels, while Labradors had a lower HR than mongrels. Labradors were found to have a sex-based difference in HR, with females having a higher HR. A higher HR was observed in young animals of all breeds when they were in contact with humans. The cage system affected the HR of Labradors and mongrels more than Beagles. Larger dogs (e.g. Labrador) have a lower HR than smaller dogs (Beagles). Animals that are younger were found to have more HR variability and have a higher HR than older animals. In addition, older animals reacted less to the application period and human interaction than younger animals. The HR response of animals inside a cage system may depend on the cage system in which they were bred. A familiar cage system typically has less impact on HR.

DISCUSSION

This retrospective data base evaluation has demonstrated the impact of environmental and biological factors on cardiovascular parameters in the context of performing safety pharmacology studies. Breed, sex, age and the type of cage system used affected, at least in some cases, the HR and its variability. They should therefore be carefully considered when designing safety pharmacology studies to have the highest possible test sensitivity.

Big data from small animals: integrating multi-level environmental data into the Dog Aging Project

Environmental exposures can have large impacts on health outcomes. While many resources have been dedicated to understanding how humans are influenced by the environment, few efforts have been made to study the role of built and natural environmental features on animal health. The Dog Aging Project (DAP) is a longitudinal community science study of aging in companion dogs. Using a combination of owner-reported surveys and secondary sources linked through geocoded coordinates, DAP has captured home, yard and neighbourhood variables for over 40,000 dogs. The DAP environmental data set spans four domains: the physical and built environment; chemical environment and exposures; diet and exercise; and social environment and interactions. By combining biometric data, measures of cognitive function and behaviour, and medical records, DAP is attempting to use a big-data approach to transform the understanding of how the surrounding world affects the health of companion dogs. In this paper, the authors describe the data infrastructure developed to integrate and analyse multi-level environmental data that can be used to improve the understanding of canine co-morbidity and aging.

Ex-vivo biomechanical analysis of an original repair of canine calcaneal tendon rupture using a synthetic implant as mechanical support fixed by sutures in the proximal tendinous part and by an interference screw in the bone distal part

Background

Rupture of the common calcaneal tendon is the second most frequent tendon rupture in dogs and may lead to severe lameness and pain. Surgical repair consists of re-apposition of the damaged tendon ends using sutures, but this type of repair is not always possible especially if the tendon has retracted. Tendon augmentation with an ultra-high molecular weight polyethylene (UHMWPE) implant is a recent solution to support the sutures and allow the repair of the canine calcaneal tendon. However, its biomechanical fixation strength remains untested for this pathology.

Aim

To evaluate the biomechanical fixation strength of a UHMWPE implant for the repair of the canine calcaneal tendon.

Methods

Ex-vivo biomechanical study was carried out on eight cadaveric hindlimbs from four adult dogs. Hindlimbs were tested under two independent modalities: proximal tendinous fixation (PTF) and distal calcaneus fixation (DCF), using a testing machine. PTF was achieved by eight simple interrupted polypropylene sutures performed through the UHMWPE implant. The latter was sandwiched inside the gastrocnemius tendon, which had previously been incised over about 5 cm longitudinally, and through the tendon of the superficial digital flexor. DCF was performed using an interference screw, which locked the UHMWPE implant into a calcaneus tunnel drilled perpendicularly.

Results

Yield, failure load, and linear stiffness (mean ± SD) for the DCF modality were 920 ± 139 N, 1,007 ± 146 N, and 92 ± 15.21, respectively, which were greater than for the PTF modality (663 ± 92 N, 685 ± 84 N and 25.71 ± 5.74, respectively, p < 0.05). Failure modes were different between fixation modalities: for PTF it was suture breakage (n = 7/8), while for DCF it was implant damage and slippage (n = 8/8).

Conclusion

The biomechanical fixation strength of the UHMWPE implant was greater for DCF than that of PTF, and should be suitable for calcaneal tendon repair in dogs. The clinical prediction of rupture of this calcaneal tendon repair will occur at the level of the PTF.

Ultrasonographic appearance and possible clinical relevance of hyperechoic foci of mineralization in the canine intrahepatic biliary tree

Background

The evidence of mineralizations in the canine liver is usually considered an incidental finding of unclear clinical significance, frequently observed in small-size old dogs.

Aim

To describe the ultrasound features of intrahepatic biliary tree foci of mineralization, to assess their clinical relevance and their possible relationship with other gastrointestinal pathological disorders.

Methods

A retrospective analysis evaluating the database of canine patients admitted to two referral veterinary centers we carried out. All dogs under study underwent an abdominal ultrasound examination in which intrahepatic biliary tree mineralization was found. Clinical and anamnestic data of the included dogs were reviewed.

Results

Approximatively 90% of the patients showed ultrasonographic abnormalities regarding the biliary system, and over 85% presented ultrasonographic abnormalities of the hepatic parenchyma. In 81.2% of dogs, ultrasonographic anomalies in the digestive tract were observed. In approximately half of our patients, we evidenced increased liver enzymes (alkaline phosphatase, alanine aminotransferase, and gamma-glutamyl transferase). At the clinical evaluation, 84.4% (23 out of 32 dogs) of patients showed signs of gastrointestinal disease that persisted for over 3 months.

Conclusion

The presence of intrahepatic biliary tree mineralizations is an unusual and frequently incidental finding that could be related to a bile stasis condition, a chronic inflammatory disease involving the biliary system and the hepatic parenchyma, and it could be associated with a liver-gut axis alteration.

Frequency of non-generalized tonic clonic seizures in a referral population of dogs

Absence seizures are a type of generalized onset seizure associated in humans with brief activity interruptions, unresponsiveness and staring. Absence seizures are infrequently reported in veterinary patients, visually indistinguishable from focal seizures, and so may be grouped as non-generalized tonic clonic seizures (non-GTCS). The objective of this retrospective study was to provide a preliminary understanding of the frequency of non-GTCS in dogs and estimate its prevalence by evaluating the distribution of seizure types presented to a referral hospital over 4 years (May 2017-April 2021), as determined from the medical record history and electroencephalography (EEG) diagnostic testing where available. A total of 528 cases were included via a medical record search for dogs with epilepsy and/or seizures presented to the neurology or emergency services. Cases were categorized into seizure types based on reported clinical signs. Each year, 53-63 % of seizure cases were described as generalized tonic clonic seizures (GTCS), 9-15 % GTCS with additional events and 29-35 % suspected non-GTCS. EEG confirmed absence seizures in 12 of 44 EEGs, 5 cases having a history of GTCS and seven without prior GTCS. This preliminary study suggests that non-GTCS may be relatively common as one third of seizure cases in the referral population presented with non-GTCS clinical signs. Prospective studies using EEG are merited to definitively determine the prevalence of these different seizure types in dogs. Acknowledging the impact of these seizures will improve awareness, aiding veterinarians in their recognition, diagnosis and potential treatment options.

Retrospective analyses of heartworm (Dirofilaria immitis) disease and ectoparasite preventive medication compliance in veterinary practices in the USA

BACKGROUND

Compliance failure with administration of heartworm (HW) disease preventives has been reported as the main contributor to HW disease incidence in medicalized dogs. This study aimed to evaluate purchase compliance with different canine HW preventive products in the USA.

METHODS

Anonymized transaction data from clinics throughout the USA served as the basis for two retrospective analyses. We first examined the monthly equivalent doses of HW preventive purchases from clinics that had implemented extended-release moxidectin injectables ProHeart^® 6 (PH6) and/or ProHeart^® 12 (PH12) compared to clinics that prescribed monthly HW preventatives (MHWP) only. In the second analysis, the purchase compliance in practices that dispensed only flea and tick (FT) and HW products separately but did not dispense combination products (dual-therapy practices) was compared to the purchase compliance with the combination product Simparica Trio^® (sarolaner, moxidectin, and pyrantel chewable tablets), purchased in clinics having implemented combination therapy in their formulary (combination-therapy practices). In both analyses, the numbers of monthly doses dispensed annually per dog were calculated.

RESULTS

Transaction data from 3,539,990 dogs in 4615 practices were included in the first analysis. In dogs administered PH12 or PH6, the numbers of monthly equivalent doses were 12 and 8.1, respectively. In both clinic types, the average annual number of MHWP doses totaled 7.3. In the second analysis, a total of 919 practices were identified as combination-therapy practices and 434 as dual-therapy-only practices. A total of 246,654 dogs (160,854 dogs in dual-therapy practices and 85,800 dogs in combination-therapy practices) were included in the calculation of the average annual number of monthly doses, which totaled 6.8 (HW preventive products) and 4.4 (FT products) in dual-therapy practices compared to 7.2 months for both FT and HW preventives with Simparica Trio^® across both practice types.

CONCLUSIONS

The injectable HW preventive PH12 is the only product that provides 12 months of heartworm disease prevention in a single veterinarian-administered injection. When choosing a monthly preventive, the combination therapy was associated with a greater purchase compliance compared with FT and HW products being dispensed separately.

Treatment of dogs with Bravecto® (fluralaner) reduces mosquito survival and fecundity

BACKGROUND

Mosquitoes serve as the vector of canine heartworm (Dirofilaria immitis), which represents a significant and persistent threat to canine health. A reduction in the longevity and/or reproductive success of mosquitoes that take a blood meal from fluralaner-treated dogs may consequently reduce the local transmission of heartworm and prevent new infections. A novel secondary effect of an oral formulation of the ectoparasiticide fluralaner (Bravecto®) against a laboratory strain of the mosquito Aedes aegypti, a potential major vector of canine heartworm, was investigated in this study.

METHODS

Six dogs were administered a single dose of fluralaner orally in the form of Bravecto® Chews (at the labeled fluralaner dose of 25 mg/kg body weight), while six control dogs received no treatment. Mosquitoes were fed on blood that was collected from each dog prior to treatment and weekly for 15 weeks post-treatment to assess the continued effects of fluralaner as its serum level decreased. Mosquito fitness was assessed by three parameters: rate of successful blood-feeding, survival, and egg laying.

RESULTS

Successful blood-feeding rate was similar between control and treatment groups. In the fluralaner treatment, mosquito survival was significantly reduced within the first 24 h after blood-feeding, for the first 12 weeks post-treatment of the dogs (efficacy range = 33.2-73.3%). Survival of mosquitoes up until a potentially heartworm-infective timepoint (14 days post-blood-feeding) was significantly reduced in the fluralaner-treated group at several timepoints (1, 2, 5, 11, 12, 13, 14, and 15 weeks post-treatment; efficacy range = 49.4-91.4%), but was less consistently reduced at the other timepoints. Egg laying by mosquitoes was almost completely suppressed for the first 13 weeks following treatment of the dogs with fluralaner (treatment efficacy ≥ 99.8%).

CONCLUSIONS

Mosquitoes fed blood from fluralaner-treated dogs experienced a significant reduction in survival and fecundity. These findings support the potential for a reduction in heartworm transmission directly by lethal effects on the vector and indirectly through a reduction of the local vector population when mosquitoes are exposed to animals treated with fluralaner.

Thoracic and abdominal aortic alterations in dogs affected with systemic hypertension

Aortic remodeling is the consequence of untreated systemic hypertension along with aortic dilatation as a marker for target organ damage in human literature. Therefore, the present study was planned to detect the changes in aorta at the level of aortic root via echocardiography, thoracic descending aorta via radiography and abdominal aorta via ultrasonography in healthy (n = 46), diseased normotensive (n = 20) and systemically hypertensive dogs (n = 60). The aortic root dimensions were measured at the level of aortic annulus, sinus of valsalva, sino-tubular junction and proximal ascending aorta via left ventricular outflow tract view of echocardiography. The thoracic descending aorta was subjectively assessed for any disparity in size and shape of aorta via lateral and dorso-ventral view of chest radiography. The abdominal aorta was assessed via left and right paralumbar window for calculating the aortic elasticity along with aortic and caudal venacaval dimensions to calculate the aortic-caval ratio. The aortic root measurements were dilated (p < 0.001) in systemically hypertensive dogs with a positive correlation (p < 0.001) with systolic blood pressure (BP). Thoracic descending aorta was also (p < 0.05) altered in the size and shape (undulation) of systemically hypertensive dogs. Abdominal aorta was markedly stiffened with reduced elasticity (p < 0.05) along with dilatation (p < 0.01) in hypertensive dogs. Also, there was a positive correlation (p < 0.001) of aortic diameters and aortic-caval ratio and negative correlation (p < 0.001) of aortic elasticity with systolic BP. Therefore, it was concluded that aorta could be considered as an important target organ damage of systemic hypertension in dogs.

Assessment of the nasal microbiota in dogs with fungal rhinitis before and after cure and in dogs with chronic idiopathic rhinitis

BACKGROUND

Pathogenesis of canine fungal rhinitis is still not fully understood. Treatment remains challenging, after cure turbinate destruction may be associated with persistent clinical signs and recurrence of fungal rhinitis can occur. Alterations of the nasal microbiota have been demonstrated in dogs with chronic idiopathic rhinitis and nasal neoplasia, although whether they play a role in the pathogenesis or are a consequence of the disease is still unknown. The objectives of the present study were (1) to describe nasal microbiota alterations associated with fungal rhinitis in dogs, compared with chronic idiopathic rhinitis and controls, (2) to characterize the nasal microbiota modifications associated with successful treatment of fungal rhinitis. Forty dogs diagnosed with fungal rhinitis, 14 dogs with chronic idiopathic rhinitis and 29 healthy control dogs were included. Nine of the fungal rhinitis dogs were resampled after successful treatment with enilconazole infusion.

RESULTS

Only disease status contributed significantly to the variability of the microbiota. The relative abundance of the genus Moraxella was decreased in the fungal rhinitis (5.4 ± 18%) and chronic idiopathic rhinitis (4.6 ± 8.7%) groups compared to controls (51.8 ± 39.7%). Fungal rhinitis and chronic idiopathic rhinitis groups also showed an increased richness and α-diversity at species level compared with controls. Increase in unique families were associated with fungal rhinitis (Staphyloccaceae, Porphyromonadaceae, Enterobacteriaceae and Neisseriaceae) and chronic idiopathic rhinitis (Pasteurellaceae and Lactobacillaceae). In dogs with fungal rhinitis at cure, only 1 dog recovered a high relative abundance of Moraxellaceae.

CONCLUSIONS

Results confirm major alterations of the nasal microbiota in dogs affected with fungal rhinitis and chronic idiopathic rhinitis, consisting mainly in a decrease of Moraxella. Besides, a specific dysbiotic profile further differentiated fungal rhinitis from chronic idiopathic rhinitis. In dogs with fungal rhinitis, whether the NM returns to its pre-infection state or progresses toward chronic idiopathic rhinitis or fungal rhinitis recurrence warrants further investigation.

Effect of progesterone on in vitro meiotic maturation of canine oocytes associated with Cx37 and Cx43 gene expression

Progesterone (P4) concentrations in canines are exceptionally high in the periovulatory period. However, the mechanisms by which P4 modulates final oocyte development in dogs remain to be characterized. The aim of this study was to evaluate the effect of P4 on meiotic development related to the gene expression of connexin 37 (Cx37) and connexin 43 (Cx43) in the canine cumlus oocyte complexes (COCs). COCs were isolated from 120 canine ovaries after a routine ovariohysterectomy. In each experiment, groups of COCs retrieved from the antral follicles were subjected to in vitro maturation (IVM) for 72 h without (control) or with P4 (50 μg/mL and 100 μg/mL) or the P4 receptor antagonist, aglepristone (RU534 at 1 μM and 10 μM). Some of the COCs recovered (from each group) after 72 h of IVM were subjected to meiotic evaluation; the remaining COCs, and those not subjected to IVM, were used to analyze the gene expression of Cx37 and Cx43 by qPCR. The results were evaluated using ANOVA. The addition of P4 increased (P < 0.05) the meiotic development compared to that in the control or aglepristone groups. The highest (P < 0.05) percentage of oocytes in the MII stage was observed upon P4 supplementation. In contrast, the highest percentage (P < 0.05) of oocytes arrested in the GV stage and the lowest (P < 0.05) percentages in the MII stage were observed for COCs cultured with aglepristone. Although a significant decrease in the mRNA levels of both connexins was observed after culturing, no effect on Cx37 and Cx43 gene expression was observed when exogenous P4 was added compared to those of the control group. However, COCs cultured with aglepristone exhibited higher (P < 0.05) expression of Cx37 and Cx43 than COCs in the control IVM-group, regardless of the concentration. In conclusion, our results suggest that a high dosage of P4 during IVM enhances the nuclear maturation of canine oocytes without altering the gene expression levels of Cx37 and Cx43. However, the increase in their expression upon treatment with a P4 antagonist indicates an in vivo role for this hormone in the endogenous modulation of both Cx37 and Cx43.

Progress towards dog-mediated rabies elimination in PR China: a scoping review

BACKGROUND

Rabies continues to be a serious threat to global public health endangering people's health and public health safety. In the People's Republic of China, multi-sectoral and comprehensive prevention and control strategies have aimed to extensively curb human rabies transmission. Here, we examine the current state of rabies infection in China, explore strategic interventions put in place in response to WHO's ambition of "Zero rabies deaths by 2030" and critically assess the constraints and feasibility of dog-mediated rabies elimination in China.

METHODS

This study analyzed and evaluated the process towards dog-mediated rabies elimination in China from five perspectives: namely, human, dog, policy, challenge, and prospects. Evidence-based data on progress of dog-mediated rabies elimination in China was derived from a number of sources; a literature search was undertaken using PubMed, Web of Science and CNKI databases, distribution data for human rabies cases as derived from the Data-center of the China Public Health Science and policy and document data were obtained from official websites of the relevant China ministries and commissions.

RESULTS

The incidence of human rabies cases in China have shown a downward trend year-on-year since 2007. Implementation of a government-led, multi-sectoral "One Health" approach to combating rabies has driven down the total number of rabies deaths nationwide to around 200 in 2020. The number of provincial-level administrative divisions (PLADs) reporting human cases of rabies has also decreased to 21 in 2020, 13 of which reported less than 10 cases. Furthermore, the number of outpatient visits seeking rabies post-exposure prophylaxis has risen dramatically over the past two decades, with demand being 15 times higher than it was initially. There remain however, significant gaps in rabies elimination outcomes across the different regions of China. To date the target of achieving a canine rabies vaccination rate of > 75% has not been met. The challenges of rabies immunization of dogs and dog management in underdeveloped cities and rural areas need to be addressed together with more effective animal surveillance and rabies risk from and too wildlife and livestock.

CONCLUSIONS

The Chinese government-led, multi-sectoral "One Health" approach to combating rabies and has made significant progress over the past decade. Development and adoption of more cost-effective One Health strategies can achieve more nationally beneficial rabies elimination outcomes. The ambitious target of "Zero rabies deaths by 2030" can be met through establishment of long-lasting herd immunity in dogs by means of dog mass vaccination campaigns, dog population management, epidemiological surveillance and the application of large-scale oral rabies vaccine to eliminate rabies in wild animals coupled with deployment of cost-effective human post-exposure prophylaxis, and community education.

Non-deflating balloon during pulmonary valvuloplasty

A 3-year-old, 4.8 kg, male intact, mixed breed dog was referred for balloon pulmonary valvuloplasty (BPV). Echocardiography was consistent with severe type A pulmonic stenosis and BPV was recommended. During BPV, the balloon catheter failed to deflate despite multiple attempts at repositioning and the use of different deflation syringes. After approximately two minutes of cardiopulmonary arrest, forceful retrograde traction resulted in removal of the fully inflated balloon. Cardiopulmonary resuscitation was unsuccessful. Post-mortem evaluation by a board-certified pathologist identified rupture of the cranial vena cava and hemothorax, suspected to be secondary to forceful removal of the fully inflated balloon. Manufacturer's evaluation of the balloon catheter used in the procedure identified multiple kinks and a segment of stretched catheter shaft suspected to be the cause for the inability to deflate. A manufacturing defect present prior to use or predisposing to stretching of the catheter segment could not be ruled out. Kinking and/or stretching of the catheter during BPV were possible causes as well. Although the inability to deflate a balloon catheter seems to be a very rare occurrence, it should be considered as a potential complication of BPV.

and others vector-borne pathogens in private-owned dogs and cats, Egypt

Vector-borne pathogens have been increasingly investigated for their impact on dog and cat health and their zoonotic potential. The aim of this study was to investigate the prevalence estimates of selected vector-borne pathogens in client-owned pets from the Giza and Cairo governorates, Egypt.  Out of 200 dogs and 100 cats, 94 (47%) and 23 (23%) were positive for at least one of the tested pathogens (P<0.0001). In particular, 84 (42%) dogs and 3 (3%) cats tested PCR-positive for Bartonella spp. (P<0.0001). A significantly higher prevalence of Bartonella spp. was detected in dogs from the rural areas of the Giza governorate (60/77, 79.2%, P<0.0001) compared to those from Cairo governorate. Bartonella henselae was the dominant species infecting dogs (81/200, 40.5%) followed by Candidatus Bartonella merieuxii (3/200, 1.5%), while B. henselae (2/100, 2%) and B. clarridgeiae were rare in cats. Haemoplasma DNA was detected in 17% (34/200) of dogs and 20% (20/100) of cats with increased risk in dogs from Giza rural areas (21/77, 27.27%, P=0.002) and from both dogs (16/63, 25.40%, P=0.03) and cats (7/14, 50%, P<0.002) with anemia. Candidatus Mycoplasma haematoparvum (30/200, 15%) and Mycoplasma haemocanis (4/200, 2%) in dogs and Candidatus Mycoplasma haemominutum (18/100, 18%) and M. haemofelis (2/100, 2%) in cats were detected. Additionally, 2 dogs were positive for C. burnetii DNA. Coinfections were detected in dogs, with the majority (23/200, 11.5%) including B. henselae and C.M. haematoparvum, followed by Mycoplasma haemocanis and C.M. haematoparvum (2/200, 1%) and B. henselae, CMhp and C. burnetii (2/200, 1%). Haemoplasma infection was high in Egyptian dogs and cats with a high prevalence for zoonotic Bartonella spp. in dogs with anemia, highlighting the need to investigate these agents in the diagnostic algorithm of anemia and to adopt preventive measures to protect both animal and human health.

The erythrocyte sedimentation rate (ESR) in canine inflammation

The clinical application of the erythrocyte sedimentation rate (ESR) assay is challenging due to its long processing time. However, in 2020 a new automated instrument for veterinary ESR was released and validated. This study sought: (1) to refine the proposed reference range (reference interval, RI) for canine ESR; (2) to compare the ESR values of healthy and sick dogs; and (3) to correlate ESR with other inflammatory markers such as C-reactive protein (CRP), fibrinogen, albumin:globulin ratio (A/G), and neutrophil-to-lymphocyte ratio (NLR); and also (4) to study ESR behavior across illnesses of varying durations. A prospective cohort study of 396 client-owned dogs (n = 120 healthy and n = 276 sick dogs) was conducted. Animals with a full clinical evaluation, complete hematobiochemical profile and a final diagnosis were included. ESR was performed according to manufacturer's instructions using the same 1 mL K3-EDTA tube used for the complete blood count. The RI was established at 1-8 mm/h in 14 min. Sick dogs had a significantly faster ESR (median 10 mm/h) than healthy dogs (median 1 mm/h; P < 0.0001). ESR was positively correlated with NLR (r = 0.36), CRP (r = 0.18) and fibrinogen (r = 0.56) and negatively correlated with A/G (r = -0.37). Dogs with an acute-on-chronic disease had the highest ESR values (median 17 mm/h) compared with either acute (median 11 mm/h; P < 0.001) or chronic diseases (median 7 mm/h; P = 0.001). ESR was confirmed as a reliable canine inflammatory marker, positively correlating with the main inflammatory markers in dogs and significantly different between sick and healthy dogs. The ESR assay appears useful especially in dogs with an acute clinical presentation, with or without an underlying chronic condition.

Cross-reactivity of human monoclonal antibodies with canine peripheral blood mononuclear cells

In drug development, the dog is often used as a model for non-rodent preclinical safety studies. In particular, immunophenotyping in dogs can be important to characterize the toxicological profile of a test item. A wide range of antibodies specific to surface antigens is needed, however, commercially available antibodies to dog are scarce. To date, numerous studies have reported the cross-reactivity of human monoclonal antibodies with canine peripheral blood mononuclear cells (PBMC). In this study, we aimed to increase the number of canine-specific antibodies and took a rather novel approach to further determine cross-reactivity of 378 human recombinant antibodies lacking Fc regions to surface antigens on canine PBMC. The screening resulted in 30 human monoclonal antibodies well reactive to canine PBMC. Sequence homology of the targeted human and canine antigens was analyzed with Basic Local Alignment Search Tool. Thirteen human cross-reactive antibodies of interest were analyzed with cells from canine whole blood in combination with lineage markers. Finally, ten antibodies were identified as useful markers for the application in dog. Except for CD27, the remaining nine antibodies are already commercially available human cross-reactive antibodies. This study provides a new source for all ten antibodies described here.

Effects of heat stress on sperm quality of French Bulldogs

This study aimed to evaluate the effects of heat stress (HS) and its duration on semen quality, serum testosterone, pulsatility and resistibility index of the testicular artery of French Bulldogs. Eight male French Bulldogs, 3-7 years old, 12.63 ± 1.8 Kg were adapted and trained for two months. Room temperature was 21 °C. Semen was collected by digital stimulation. The median of four andrological evaluations was T0. Heat was applied to the scrotum using an electrical heat pad at 40 °C for 11 min. Rectal temperature (RT) and scrotum temperature were evaluated using a mercury thermometer and an infrared thermography camera before and after HS. Semen was evaluated immediately (T1) and after seven (T7), 14 (T14), 21 (T21), 28 (T28) and 60 (T60) days after HS. Semen parameters included macroscopic (volume, color and viscosity) and microscopic (sperm motility and vigor, percentage of morphologically normal or defected spermatozoa, sperm concentration and total number of sperm cells) aspects. A pulsed colored doppler ultrasound was performed on the testicular artery at the spermatic cord and epididymis region before and immediately after HS. Serum testosterone was analyzed before, 48 and 96 h after HS. Data was analyzed by ANOVA using SAS. There was a 1.23 °C increase on RT and a 4.98 °C increase on thermograph after HS. Sperm motility decreased at T1 (P < 0.05) and tended to stay lower at T7 (P = 0.056). It improved at T14, but reduced again at T21 (P < 0.05). At T28 and T60 motility was normal. Vigor was lower at T1 (P < 0.05), normal at T7 and T14, but decreased at T21 (P = 0.054), at T28 and T60 it was not different than T0. Sperm concentration was lower at T1 (P < 0.05) and not different from T0 at other timepoints. Volume color and viscosity were not different. Total sperm per ejaculate was reduced at T1 and T7 (P < 0.05) and tended to be lower at T14 (P = 0.057). T21, T28 and T60 were not different than T0. There was a decrease in normal sperm cells and an increase in defected sperm at T7. There was no difference within T14, T21, T28 and T60. The raise in pathologies at T7 was from an increase in minor defects (P < 0.05). There was no difference in serum concentration of testosterone nor pulsatility and resistivity index before and after HS. In conclusion, induction of HS directly to the testis reduces sperm quality in French Bulldog. This impairment is immediately and transitory.

Genomic analysis of firework fear and noise reactivity in standard poodles

BACKGROUND

Fear of firework noises and other loud, sudden noises (noise reactivity) is a significant problem for many dogs and may have a negative effect on both welfare and, in severe cases, the life expectancy of dogs. A wide range of behavior traits, including fear-related behaviors, have high heritability estimates in dogs. The aim of this study was to estimate genomic heritability for fear of fireworks and loud noises in dogs.

RESULTS

A genomic heritability estimate was performed based on genome-wide SNPs from standard poodles with records of fear of fireworks and noise reactivity. The study was based on questionnaires answered by owners, who also volunteered to return a cheek swab from their dog for DNA analyses. SNP-based heritability was estimated to be 0.28 for firework fear and 0.16 for noise reactivity. We also identified an interesting region on chromosome 17 that was weakly associated with both traits.

CONCLUSIONS

We have estimated low to medium genomic heritabilities for fear of fireworks and noise reactivity in standard poodles. We have also identified an interesting region on chromosome 17, which harbors genes that have been shown to be involved in different psychiatric traits with anxiety components in humans. The region was associated with both traits; however, the association was weak and need further verification from other studies.

Cushing Syndrome and Other Causes of Insulin Resistance in Dogs

The most common causes of insulin resistance in diabetic dogs are Cushing syndrome, diestrus, and obesity. Cushing-associated effects include insulin resistance, excessive postprandial hyperglycemia, perceived short duration of insulin action, and/or substantial within-day and/or day-to-day glycemic variability. Successful strategies to manage excessive glycemic variability include basal insulin monotherapy and combined basal-bolus insulin treatment. Ovariohysterectomy and insulin treatment can achieve diabetic remission in about 10% of cases of diestrus diabetes. Different causes of insulin resistance have an additive effect on insulin requirements and the risk of progression to clinical diabetes in dogs.

Diabetes Ketoacidosis and Hyperosmolar Hyperglycemic Syndrome in Companion Animals

Diabetes mellitus is a common endocrinopathy in dogs and cats. Diabetes ketoacidosis (DKA) and hyperosmolar hyperglycemic state (HHS) are life-threatening complications of diabetes resulting from an imbalance between insulin and the glucose counter-regulatory hormones. The first part of this review focuses on the pathophysiology of DKA and HHS, and rarer complications such as euglycemic DKA and hyperosmolar DKA. The second part of this review focuses on the diagnosis and treatment of these complications.

MCP-1/IL-12 ratio expressions correlated with adventitial collagen depositions in renal vessels and IL-4/IFN-γ expression correlated with interstitial collagen depositions in the kidneys of dogs with canine leishmaniasis

Collagen deposition is a common event in chronic inflammation, and canine Leishmaniosis (CanL) is generally associated with a long and chronic evolution. Considering that the kidney shows fibrinogenic changes during CanL, and the balance of cytokines/chemokines regulates the profibrinogenic and antifibrinogenic immune responses differently, it can be hypothesized that the balance of cytokines/chemokines can be differentially expressed in the renal tissue in order to determine the expression of collagen depositions in the kidneys. This study aimed to measure collagen deposition and to evaluate cytokine/chemokine expressions in the kidney by means of qRT-PCR in sixteen Leishmania-infected dogs and six uninfected controls. Kidney fragments were stained with hematoxylin & eosin (H&E), Masson's Trichrome, Picrosirius Red, and Gomori's reticulin. Intertubular and adventitial collagen depositions were evaluated by the morphometric approach. Cytokine RNA expressions were measured by means of qRT-PCR to identify molecules involved in chronic collagen depositions in kidneys with CanL. Collagen depositions were related to the presence of clinical signs, and more intense intertubular collagen depositions occurred in infected dogs. Adventitial collagen deposition, as morphometrically measured by the average area of the collagen, was more intense in clinically affected dogs than in subclinically infected dogs. TNF-α/TGF-β, MCP1/IL-12, CCL5/IL-12, IL-4/IFN-γ, and IL-12/TGF-β expressions were associated with clinical manifestations in dogs with CanL. The IL-4/IFN-α ratio was more commonly expressed and upregulated in clinically affected dogs, and downregulated in subclinically infected dogs. Furthermore, MCP-1/IL-12 and CCL5/IL-12 were more commonly expressed in subclinically infected dogs. Strong positive correlations were detected between morphometric values of interstitial collagen depositions and MCP-1/IL-12, IL-12, and IL-4 mRNA expression levels in the renal tissues. Adventitial collagen deposition was correlated with TGF-β, IL-4/IFN-γ, and TNF-α/TGF-β. In conclusion, our results showed the association of MCP-1/IL-12 and CCL5/IL-12 ratios with an absence of clinical signs, as well as an IL-4/IFN-α ratio with adventitial and intertubular collagen depositions in dogs with visceral leishmaniosis.

Evaluation of a small-bore needle arthroscope for diagnosis and treatment of medial coronoid disease in dogs: a pilot study with short-term assessment

CASE HISTORY

Dogs (n = 15) that were presented to a single veterinary teaching hospital with elbow dysplasia-associated lameness between September 2021 and May 2022, and were determined to require arthroscopy based on imaging results, were prospectively recruited into the study. The median duration of lameness was 4 (min 1, max 24) months.

CLINICAL FINDINGS

Various breeds were represented with a median body weight of 31.6 (min 15, max 46.4) kg and median age at presentation of 14 (min 8, max 83) months. Results of imaging modalities (CT) were consistent with medial coronoid disease with fissured or fragmented medial coronoid process in all dogs.

ARTHROSCOPIC FINDINGS

Feasibility of the needle arthroscopy (NA) procedure was firstly assessed in a preliminary cadaveric study in forelimbs (n = 10) collected from 10 adult dogs euthanised for reasons unrelated to the study. Elbow exploration was performed through a medial approach beginning with NA (1.9 mm 0° angle scope) followed by standard arthroscopy (SA; 2.4 mm 30° angle scope). The quality and extent of visualisation (scored through the number of anatomical structures visualised) were recorded and statistically compared. As the cadaver study indicated that NA allowed safe inspection of all structures in medial/caudal compartments, this procedure was then used in the dogs requiring treatment. In the clinical setting, elbow exploration was successful in all dogs and the treatment (removal of osteochondral fragments) was performed without requiring conversion into SA. One month after surgery, all dogs had an improvement in their lameness score (0-5) and 12/15 dogs were no longer lame. There was a reduction in Canine Orthopaedic Index scores measured a median of 99 (min 47, max 180) days after surgery (24 (IQR 19.5-31.5)) compared to the pre-operative period (49 (IQR 46.5-57); p < 0.001).

CLINICAL RELEVANCE

Needle arthroscopy-assisted removal of osteochondral fragments was performed in all dogs with satisfactory short-term clinical outcome. NA is a feasible technique for diagnosis and lesion assessment in dogs with a fissured or fragmented coronoid process. Larger clinical studies with longer follow-up are necessary to validate the NanoScope operative arthroscopy system as an alternative strategy to SA for video-assisted treatment of medial coronoid disease.

Changes in Lactate-related Fecal Microbiome in Hyperlactatemia Diabetic Dogs

BACKGROUND/AIM

The correlation between the intestinal microbiome and endocrine disorders has recently been drawing attention as an important key for determining their pathology and clinical assessment. In this study, we evaluated the microbiome of dogs with insulin-dependent diabetes mellitus (IDDM) with respect to blood lactate.

MATERIALS AND METHODS

Fecal samples were obtained from 17 subjects and real-time quantitative polymerase chain reaction determinations were performed to quantify the gene expression levels of lactate-producing and dysbiosis index-related bacteria.

RESULTS

Expression levels of the lactate-producing bacteria Lactobacillus spp., Enterococcus spp., and Bifidobacterium spp., were confirmed in patients with high concentrations of lactate in the blood. The abundance of Enterococcus and Bifidobacterium was higher in diabetic dogs compared to that of non-diabetic dogs. When blood lactate concentrations were high, the abundance of Bifidobacterium also increased.

CONCLUSION

Blood lactate levels influence the gut microbiome in dogs with IDDM. This study will help understand the gut microbiota in the context of diabetes in human and veterinary medicine.

Translational veterinary epilepsy: A win-win situation for human and veterinary neurology

Epilepsy is a challenging multifactorial disorder with a complex genetic background. Our current understanding of the pathophysiology and treatment of epilepsy has substantially increased due to animal model studies, including canine studies, but additional basic and clinical research is required. Drug-resistant epilepsy is an important problem in both dogs and humans, since seizure freedom is not achieved with the available antiseizure medications. The evaluation and exploration of pharmacological and particularly non-pharmacological therapeutic options need to remain a priority in epilepsy research. Combined efforts and sharing knowledge and expertise between human medical and veterinary neurologists are important for improving the treatment outcomes or even curing epilepsy in dogs. Such interactions could offer an exciting approach to translate the knowledge gained from people and rodents to dogs and vice versa. In this article, a panel of experts discusses the similarities and knowledge gaps in human and animal epileptology, with the aim of establishing a common framework and the basis for future translational epilepsy research.

Effects of proactive interference on olfactory memory in dogs

Proactive interference (PI) occurs when memories of past events or stimuli intrude in the present moment, causing working memory (WM) errors. These errors are often measured through WM tests such as matching-to-sample (MTS). When the repetition of individual stimuli increases, there is a greater chance of these intrusions, and thus there can be a decrease in accuracy in such tasks. In two experiments, we explored the nature of PI on dog working memory. First, we manipulated the size of the set of odors (2, 6, trial-unique) used to construct each session to maximize (2-odor set) and minimize (trial-unique) within-session proactive interference during an olfactory MTS task. Matching-to-sample accuracy decreased with greater PI. Second, we adapted procedures originally designed for pigeons and rhesus macaques to determine the locus of PI in dogs. To test for proactive interference, probe trials were inserted into MTS sessions where sample odors from earlier trials reappeared as incorrect comparisons. Incorrect responses on these probe trials indicated proactive interference. These probe tests were conducted with a 0-s or 20-s retention interval in separate sessions. We found that dogs performed worse on the matching task when the source of interference (odor stimulus) was from the immediately preceding trial compared with when they were from trials further back in the session but only for the 0-s retention interval. These results are compared with previous work examining the effects of proactive interference on working memory in other species.

Single-cell hemoprotein (heme-SCP) exerts the prebiotic potential to establish a healthy gut microbiota in small pet dogs

To investigate the effect of the single-cell hemoprotein (heme-SCP) source on animals, a dog-treat (100 g for each dog) harboring 0.2% heme-SCP was manufactured and fed to seven pet dogs (< 10 kg) in a randomized manner (irrespective of owner's feeding style, dogs' health conditions, and staple diets), and the feces before and after the dog-treat diet were analyzed to define the structure of the microbiota. The total bacterial species of the seven dogs showed no difference (564-584), although the bacterial compositions varied significantly. The Firmicutes phylum increased (54.7-73.7%), showing differential species composition before and after heme-SCP intake. Proteobacteria, Bacteroidetes, and Fusobacteria decreased (5.4-3.8%, 32.9-16.8%, and 6.3-3.6%, respectively), which agreed with the previous observation of deliberate feeding. Therefore, it is conceivable that heme-SCP as a prebiotic can shape the gut microbiota regardless of the administration method.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01195-9.

Investigation of canine chaphamaparvovirus, canine bufavirus, and canine adenovirus in dogs with diarrhea: First report of novel canine bufavirus in Turkey

Viral enteritis is a significant cause of death among dogs younger than 6 months. In this study, the presence of canine chaphamaparvovirus (CaChPV), canine bufavirus (CBuV), and canine adenovirus (CAdV) was investigated in 62 diarrheal dogs previously tested for other viral pathogens (canine parvovirus type 2, canine coronavirus, and canine circovirus). CBuV was detected in two dogs (3.22%) and CaChPV in one dog (1.61%). One dog tested positive for three parvoviruses (CPV-2b, CBuV, and CaChPV). All dogs tested negative to CAdV-1/CAdV-2. A long genome fragment of one of the two identified CBuVs and of the CaChPV was obtained and analyzed. New Turkish CBuVs had high identity rates (96%-98% nt; 97%-98% aa) with some Italian CBuV strains (CaBuV/9AS/2005/ITA and CaBuV/35/2016/ITA). The phylogenetic analysis powerfully demonstrated that these viruses belonged to a novel genotype (genotype 2). A part of the genome ChPV-TR-2021-19 revealed high identity rates (> 98% nt and > 99% aa) with some Canadian CaChPV strains (NWT-W88 and NWT-W171) and the Italian CaChPV strain Te/37OVUD/2019/IT. This study is the first report on the detection of CBuV-2 and the concomitant presence of three canine parvoviruses in Turkey. The obtained data will contribute to the molecular epidemiology and the role in the etiology of enteric disease of new parvoviruses.

Spontaneous autoimmune subepidermal blistering diseases in animals: a comprehensive review

Autoimmune subepidermal blistering diseases (AISBDs) are rare skin disorders of animals that were first identified in dogs but several AISBDs are now recognised in other companion animal species. Most AISBDs in animals are homologues of the human diseases and are thought to share similar pathomechanisms of epidermal and/or mucosal blister formation caused by autoantibodies targeting structural proteins of the basement membrane zone (BMZ). Disruption of their structural function by the autoantibodies and/or recruited inflammation leads to BMZ fragility, which presents clinically as vesicles, bullae and, later, deep erosions and ulcers. Canine AISBDs are the best characterised, particularly the more common variants such as mucous membrane pemphigoid (48%), epidermolysis bullosa acquisita (EBA) (26%), and bullous pemphigoid (10%). Exceedingly rare AISBDs in the dog are junctional EBA, mixed AISBD, type-1 bullous systemic lupus erythematosus, linear IgA dermatosis, and pemphigus gestationis. The diagnosis of a specific AISBD is made by combining the clinical features (breed, age, lesion distribution) with histological evidence of subepithelial clefting, but not all AISBDs can be differentiated in this manner and specialised immunological testing is required. This latter, unfortunately, is not readily available and, therefore, the specific AISBD diagnosis often remains unconfirmed. While this limits further understanding of these diseases, it does not prevent clinicians from treating their patients, as the treatment approaches are similar for the different AISBDs in dogs. This review primarily focuses on canine AISBDs, the species for which these diseases have been best characterised, and shorter descriptions of variants in other species are also provided.

Anesthetic Considerations in Dogs and Cats with Diabetes Mellitus

Understanding the effects of diabetes and hyperglycemia on hydration, acid-base status, and immune function is paramount to safely anesthetizing diabetic cats and dogs. Preoperative stabilization of glucose concentrations, hydration, and electrolyte imbalances is key to minimizing morbidity and mortality. Blood glucose monitoring perioperatively will help guide insulin and dextrose administration. Specific anesthetic considerations, and peri-anesthetic management of animals with diabetes mellitus, including anesthetic drugs and recommended insulin protocols are discussed.

Genetic and phenotypic analyses of mcr-harboring extended-spectrum β-lactamase-producing Escherichia coli isolates from companion dogs and cats in Japan

The emergence of mcr plasmid-mediated colistin-resistant extended-spectrum β-lactamase (ESBL)-producing Enterobacterales among companion dogs and cats poses a risk of the animals acting as reservoirs for cross-species transmission. However, current knowledge of mcr-harboring ESBL-producing Enterobacterales in companion dogs and cats is still limited; thus, the genetic and phenotypic characteristics of the bacterial isolates and plasmids, in companion dogs and cats, remain to be elucidated. Here, we identified mcr gene-harboring ESBL-producing Escherichia coli isolates during whole-genome sequencing of ESBL-producing E. coli isolates from a dog and a cat in Osaka, Japan. Colistin-resistant MY732 isolate from a dog carried two plasmids: mcr-1.1-harboring IncI2 plasmid and bla_CTX-M-14-harboring IncFIB plasmid. Conjugation assays revealed that both plasmids can be co-transferred even though the IncFIB plasmid lacked a conjugal transfer gene cassette. The other isolate MY504 from a cat harbored two bla genes and mcr-9 on the identical IncHI2 plasmid. This isolate was not resistant to colistin, which is likely to be due to deletion of the regulatory two-component QseBC system associated with the mcr-9 expression. To the best of our knowledge, this is the first report of a colistin-resistant ESBL-producing E. coli isolate harboring mcr-1 from a companion dog in Japan. Given that the mcr gene-harboring IncI2 and IncHI2 plasmids in this study shared high homology with plasmids from human or animal-derived Enterobacterales, companion dogs and cats may act as important reservoirs for cross-species transmission of the mcr gene in the community, in Japan.

Year-round tick exposure of dogs and cats in Germany and Austria: results from a tick collection study

BACKGROUND

Ticks and tick-borne diseases play a major role in companion animal health. Additionally, the European tick fauna is changing, for instance due to the spread of Dermacentor reticulatus, displaying a higher likelihood of winter activity than Ixodes ricinus. Therefore, we investigated current tick infestations in dogs and cats in Germany and in parts of Austria and the seasonal infestation risk.

METHODS

Overall, 219 veterinary practices were invited to collect ticks from cats and dogs on a monthly basis. Ticks were morphologically identified and female I. ricinus specimens were measured to estimate attachment duration.

RESULTS

In total, 19,514 ticks, 17,789 (91.2%) from Germany and 1506 (7.7%) from Austria, were received between March 2020 and October 2021, with 10,287 specimens (52.7%) detached from dogs, 8005 from cats (41.0%) and 1222 from other species (6.3%). In Germany, the most common tick species collected from dogs were I. ricinus (78.0%) and D. reticulatus (18.8%), while cats mainly harboured I. ricinus (91.3%) and I. hexagonus (5.5%) and only few D. reticulatus (0.6%). In Austria, collected I. ricinus reached similar proportions in dogs (90.4%) and cats (95.3%), followed by D. reticulatus in both dogs (5.2%) and cats (1.5%), with I. hexagonus (0.9%) collected only marginally from cats. The average infestation intensity amounted to 1.62 ticks/dog and 1.88 ticks/cat. The single to multiple infestation ratio was 79.1% to 20.9% in dogs and 69.0% to 31.0% in cats, with cats being significantly more often multiple infested than dogs, while the proportion of mixed-species infestations was 2.0% for both dogs and cats. The average attachment duration of female I. ricinus specimens amounted to 78.76 h for dogs and 82.73 h for cats. Furthermore, year-round tick exposure was confirmed, with 108 D. reticulatus and 70 I. ricinus received on average per month during December 2020 to February 2021.

CONCLUSIONS

The study shows a year-round tick infestation risk, with activity of both D. reticulatus and I. ricinus during winter, and confirms the widespread occurrence of D. reticulatus in Germany. Additionally, long average attachment durations and frequent multiple infestations underline the need for adequate year-round tick control, even during the winter months.

Echocardiographic parameters in French Bulldogs, Pugs and Boston Terriers with brachycephalic obstructive airways syndrome

BACKGROUND

In this prospective study, we hypothesized that dogs with signs of brachycephalic obstructive airway syndrome (BOAS) would show differences in left and right heart echocardiographic parameters compared with brachycephalic dogs without signs of BOAS and non-brachycephalic dogs.

RESULTS

We included 57 brachycephalic (30 French Bulldogs 15 Pugs, and 12 Boston Terriers) and 10 non-brachycephalic control dogs. Brachycephalic dogs had significantly higher ratios of the left atrium to aorta and mitral early wave velocity to early diastolic septal annular velocity; smaller left ventricular (LV) diastolic internal diameter index; and lower tricuspid annular plane systolic excursion index, late diastolic annular velocity of the LV free wall, peak systolic septal annular velocity, late diastolic septal annular velocitiy, and right ventricular global strain than non-brachycephalic dogs. French Bulldogs with signs of BOAS had a smaller diameter of the left atrium index and right ventricular systolic area index; higher caudal vena cava at inspiration index; and lower caudal vena cava collapsibility index, late diastolic annular velocity of the LV free wall, and peak systolic annular velocity of the interventricular septum than non-brachycephalic dogs.

CONCLUSIONS

The differences in echocardiographic parameters between brachycephalic and non-brachycephalic dogs, brachycephalic dogs with signs of BOAS and non-brachycephalic dogs, and brachycephalic dogs with and without signs of BOAS indicate higher right heart diastolic pressures affecting right heart function in brachycephalic dogs and those with signs of BOAS. Most changes in cardiac morphology and function can be attributed to anatomic changes in brachycephalic dogs alone and not to the symptomatic stage.

Comparison of 2 anesthetic protocols and surgical timing during cesarean section on neonatal vitality and umbilical cord blood parameters

BACKGROUND

The objective of this study was to evaluate the relationship between the mode of anesthesia, the time form the induction to the extraction of a puppy and the immediate postnatal vitality and umbilical cord blood gases parameters in cesarean section derived-puppies. Two different anesthetic protocols were used: inhalation using isoflurane (ISO) and combined-inhalation and epidural (EPI) with propofol being the induction agent.

RESULTS

Significant differences were found in ISO group in pH values, pCO2 levels and Apgar scores between puppies at different extraction times (< 30 vs. ≥ 30 min). In ISO group puppies extracted later were more acidic (7.16 vs. 7.22), had higher levels of pCO2 (69 vs. 57 mmHg) and lower Apgar scores at birth (1.2 vs. 2.5). On the contrary, in EPI group no differences were observed between the delivery time, umbilical blood gas parameters and puppies' vitality. Furthermore, the dams from the EPI group required lower concentrations of isoflurane (MAC 1.11 ± 0.19 vs.1.37 ± 0.16, p < 0.001).

CONCLUSIONS

Multiple pregnancies frequent in dogs lead to significant differences in extraction times between the first and the last puppy during cesarean section. Obtained results showed that the mode of anesthesia and the surgical time would influence the neonatal outcome during cesarean section in dogs. The higher concentration of isoflurane with the longer time of exposure had a negative effect on the initial newborn vitality as well as the umbilical cord blood gas parameters. Therefore, when performing CS in giant dog breeds or expecting many puppies in the litter, it is worth considering epidural component that allow for lower concentrations of inhalant agents, which may contribute to a better clinical condition of newborns.

Hematogenous septic arthritis of a non-prosthetic shoulder caused by Capnocytophaga canimorsus: A case report and review of the literature

Capnocytophaga canimorsus, oral inhabitants of dogs and cats is a cause of zoonotic infections. It is transmitted to humans by bites, scratches, licks, or close exposure to these animals. Infections due to Capnocytophaga canimorsus have a wide range of severity and can sometimes be fatal. We report the case of an 89-years-old man who suffered from a sudden swollen native right shoulder. The blood test revealed an inflammatory syndrome and cytologic evaluation of joint aspiration showed an elevated nucleated cells count suspicious of infection. A Gram-negative bacillus grew after 48 h in the arthrocentesis and was identified as Capnocytophaga canimorsus. After 4 days, blood culture also grew Capnocytophaga canimorsus leading to the diagnosis of hematogenous septic arthritis of a non-prosthetic right shoulder. Antimicrobial therapy was empirically started with cefuroxime then switched to doxycycline for seven weeks with good clinical outcomes. It is important to inquire about patients' environment including their proximity to animals as it can lead to zoonotic infections that can be of high severity. Moreover, hygiene rules must be applied when dog scratches or lick wounds occurred to avoid the spread of zoonotic germs. Prophylactic antibiotic therapy should be given for animal bites.