Search Results (13)

Canine mammary tumors (CMTs) constitute one of the most prevalent malignancies in female canines, whereas the functional involvement of gonadotropin receptors—luteinizing hormone receptor (LHR) and follicle-stimulating hormone receptor (FSHR)—in these neoplasms remains uncharacterized. This study investigated LHR and FSHR expression in 79 CMTs and 14 normal mammary tissues collected from 59 female dogs (ethical approval AW82903202-2-3), using immunohistochemistry (IHC) and quantitative real-time PCR, specifically examining their association with tumor malignancy and spay status. Relative to normal mammary tissue, CMTs exhibited statistically significant downregulation of both LHR and FSHR transcripts and corresponding proteins (p < 0.01), with expression progressively decreasing as tumor malignancy increased, and with grade 3 tumors showing almost undetectable levels. Notably, spayed dogs displayed higher LHR levels in tumors (p < 0.05), whereas intact dogs showed higher FSHR levels than spayed dogs. These findings suggest that the expression of LHR and FSHR in CMTs may correlate with tumor malignancy and be influenced by the spay status. Our findings provide the first evidence of gonadotropin receptor dysregulation in CMTs, offering novel insights into their molecular mechanisms and potential applications in hormone-related diagnostic or therapeutic strategies. Full article

For mammary carcinomas in pet rabbits, prognostic biomarkers are poorly defined, and treatment is limited to surgical excision. Additional treatment options are needed for rabbit patients for which surgery is not a suitable option. In human breast cancer, the immunosuppressive enzyme indoleamine 2,3-dioxygenase 1 (IDO1) represents a prognostic biomarker and possible therapeutic target. This retrospective immunohistochemical study examined IDO1 in 96 pet rabbit mammary carcinomas with known mitotic count, hormone receptor status, and percentage of stromal tumor infiltrating lymphocytes (TILs). Tumors were obtained from 96 pet rabbits with an average of 5.5 years. All rabbits with reported sex (n = 88) were female or female-spayed. Of the carcinomas, 94% expressed IDO1, and 86% had sparse TILs consistent with cold tumors. Statistically significant correlations existed between a higher percentage of IDO1-positive tumor cells, lower mitotic counts, and increased estrogen receptor expression. The threshold for significance was IDO1 staining in >10% of tumor cells. These results lead to the assumption that IDO1 expression contributes to tumorigenesis and may represent a prognostic biomarker and possible therapeutic target also in pet rabbit mammary carcinomas. They also support the value of rabbits for breast cancer research. Full article

This study aimed to investigate changes in the number of, and reasons for, requests for dogs’ euthanasia over the last thirty years. Data (breed, age, gender, neuter status, manner, and cause of death) from dogs’ euthanasia registered between 1990 and 2020 in a small animals’ veterinary hospital were analyzed. The overall period examined has been split into two terms (T1 = 1990–2004 and T2 = 2005–2020) considering the introduction and enforcement of Law 189/2004. During the whole period examined, a significant increasing trend in euthanasia cases has been recorded (p = 0.027). Comparing the two terms, we observed significant differences regarding variables such as age, breed, reproductive status, and ownership. The number of euthanized dogs was significantly higher in T1 than in T2. Dogs euthanized in T2 were older than dogs in T1. A high percentage of the euthanized dogs were crossbred and stray dogs. Additionally, the number of neutered/spayed dogs was significantly higher. Regarding the cause of death, a significantly higher percentage of neoplastic processes was detected in T2. The data here reported suggest a potential influence of Law 189/2004. This law in Italy has proven to be a legal milestone that has influenced the decision-making process between euthanasia and natural death. Full article

Mammary cancer is the most frequently diagnosed neoplasia in women and non-spayed female dogs and is one of the leading causes of death in both species. Canines develop spontaneous mammary tumors that share a significant number of biological, clinical, pathological and molecular characteristics with human breast cancers. This review provides a detailed description of the histological, molecular and clinical aspects of mammary cancer in canines; it discusses risk factors and currently available diagnostic and treatment options, as well as remaining challenges and unanswered questions. The incidence of mammary tumors is highly variable and is impacted by biological, pathological, cultural and socioeconomic factors, including hormonal status, breed, advanced age, obesity and diet. Diagnosis is mainly based on histopathology, although several efforts have been made to establish a molecular classification of canine mammary tumors to widen the spectrum of treatment options, which today rely heavily on surgical removal of tumors. Lastly, standardization of clinical study protocols, development of canine-specific biological tools, establishment of adequate dog-specific disease biomarkers and identification of targets for the development of new therapies that could improve survival and have less adverse effects than chemotherapy are among the remaining challenges. Full article

Bacterial, protozoal, and viral vector-borne pathogens (VBPs) can cause infections in cats. There is little information on feline VBP prevalence in Germany. Stray cats are frequently exposed to vectors but receive no veterinary care. The aim of this study was to determine the prevalence of selected VBPs in stray cats. EDTA blood and serum samples were taken from apparently healthy stray cats during a spay/neuter campaign in the federal state of Thuringia. Overall, 11/50 (22%) and 32/50 (64%) cats tested positive for at least one VBP by direct and indirect detection methods, respectively. PCR testing of EDTA blood detected hemotropic Mycoplasma spp. in 12% of cats, Hepatozoon spp. in 10%, and Anaplasma phagocytophilum in 4%. PCR testing for Rickettsia spp. and piroplasms was negative. IFAT on serum samples showed 46% of cats had detectable antibodies for Bartonella spp., 30% for Rickettsia spp., and 16% for A. phagocytophilum. The cats were additionally tested for feline coronavirus, FIV, and FeLV to identify potential risk factors for pathogen contact and/or infections. No correlation between FIV and FeLV status and VBP positivity was detected. Anaplasma phagocytophilum, Rickettsia spp., and Bartonella spp. have zoonotic potential, and surveillance is recommended in the context of the One Health approach. Full article

The objective of this study was to characterize the domestic cat population of Uruguay in relation to breed, coat color, hair length, lifestyle (indoor vs. outdoor), age, sex, and spay/neuter status according to a survey completed by their owners or guardians. An online survey, distributed to residents of Uruguay, was completed in full by 2561 cat guardians. Descriptive statistics and Chi-squared tests were performed. The population of cats with guardians in Uruguay is characterized by the following data: higher frequency of female cats (53%), most of the cats were between two and six years old (49%), most of them were neutered (84%, mainly those older than one year of age), most of them have outdoor access (87%), a very low percentage (6%) are purebred (Siamese being the most frequent: 86%), and within the non-pure breeds, short hair cats were the most frequent (79%). This study, in addition to expanding the information on the characteristics of cats with guardians from other countries and continents, is the first study in Latin America to describe some key demographic aspects such as cat breeds, coat color, hair length, lifestyles, and frequency by age, sex, and spay/neuter status (spayed/neutered or not) at the country level. Full article

This study was initiated in 2004 because the prevalence of feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) infections in feral cats in San Mateo County (SMC) was not known. The cities attributed to the feral cat population presented to the Peninsula Humane Society & SPCA’s Spay/Neuter Clinic and to the Shelter itself were analyzed to examine potential geographic concentrations of feral cats with positive retroviral status. Trends in FIV and FeLV status were examined in three 3-year periods (2001–2003, 2005–2007, and 2014–2016). Population trends over the 15 years of this study for feral cats admitted to the Shelter were also examined. In each study period, more female feral cats were presented to the S/N Clinic (54.06%, 57.37%, 54.89%). FIV prevalence increased from 5.52% to 6.41% (p = 0.29) from the first to third period; FeLV prevalence decreased significantly from 1.73% to 0.29% (p = 0.01). Significantly more FIV-positive males than females were identified each year and for each period (p < 0.01). The four largest SMC cities were the major source of feral cats to the Shelter, S/N Clinic, and of FIV- and FeLV-positive cats in the first two periods; in the third period, 50% of feral cats to the Shelter and of FeLV-positive cats were from these cities. Despite a 61.63% reduction in feral cat admissions to the S/N Clinic, the FIV prevalence for males remained similar and increased for females. The retrovirus prevalence suggests the need for continued testing and surveillance of FIV among SMC free-living cats. Full article

Serotonin is considered to be the neurotransmitter that controls several types of behavior: aggressiveness, impulsivity, food selection, stimulation, sexual behavior, reaction to pain, and emotional manifestations. The aim of this study was to determine the serotonin values in 43 dogs, divided into three different experimental variants: (1) between two groups of medium (n = 6) and small (n = 4) breed shelter dogs; (2) in dogs with (n = 15) and without (n = 10) owners after administration of pre-spaying/neutering anesthesia; (3) in different behavioral states (n = 8) classified as follows: M1—happy, M2—aggressive, M3—calmed status, post-exposure to a stressful situation, compared to the reference time referred to as M0. There were no significant differences (p ≥ 0.05) regarding the serotonin values between the two groups of medium and small breed shelter dogs. Following anesthesia, the average mean serotonin values were significantly lower (p ≤ 0.003), by 63.85 ng/mL, in stray dogs compared to dogs with owners. No significant differences (p ≥ 0.05) were found when comparing the reference time M0 to M1, M2, and M3. The differences decreased significantly (p ≤ 0.05), by 89.61 ng/mL, between M1 and M2 and increased significantly (p ≤ 0.008), by 112.78 ng/mL, between M2 and M3. Full article

Female dogs, especially intact or neutered lately, are at increased risk for reproductive disorders including mammary tumors (MTs). This retrospective study evaluated the prevalence of reproductive pathology and associated mortality in a cohort of female dogs presented at a single veterinary clinic. The medical records of female dogs born in 2000–2003 were reviewed. The study included 599 cases, of which 293 were followed up until death. Causes of death were analyzed according to the spaying status. Among the 599 female dogs, 306 were intact (51%), 50 (8%) had been spayed before 2 years of age (ES, early spaying), and 243 (41%) after 2 years (LS, late spaying). During their lifetime, 79 dogs (13.2%) developed pyometra, and 160 (26.7%) a mammary tumor. Among the 293 dogs with complete follow-up, 103 (35.1%) had at least one MT during their lifetime, of which 53 (51.5%) died of their mammary cancer. Spayed (ES + LS) female dogs had a 4-fold decreased risk of dying from mammary cancer (OR = 0.23, 95% CI 0.11–0.47, p < 0.0001) compared to intact females. In this low-sterilization rate population, MTs developed in 35.1% of female dogs over their lifetime and was the cause of death in half of them. Full article

Some domestic dogs aggressively guard resources. Canine resource guarding impacts public health through dog bites and affects dog welfare through adoption and euthanasia policies at animal shelters. However, little is known about the demographic characteristics and adoption success of dogs assessed as resource guarders during shelter behavioral evaluations. I reviewed nearly five years of records from a New York (NY) SPCA and categorized 1016 dogs by sex; age; size; reproductive status; and resource guarding. I then examined how these characteristics influenced the returns of dogs by adopters. The prevalence of resource guarding in this shelter dog population was 15%. Resource guarding was more common in adult and senior dogs than in juvenile dogs; and it was more common in small and large dogs than medium-sized dogs. Spayed females were more likely than intact females to guard food; neutered males and intact males did not differ in their likelihood of food guarding. Most dogs identified as resource guarders showed mild to moderate guarding. Severe guarders were more likely to be returned by adopters; although almost all were eventually re-adopted and not returned to the shelter. Data presented here provide the most comprehensive description of resource guarders in a shelter dog population and show the successful re-homing of most. Full article

The aim of this review is to raise awareness for mammary tumors in rabbits and to report progress in related research. Currently, a standardized tumor classification for rabbits is not available, prognostic factors are unknown and the only treatment option is surgical excision. Studies showed that affected rabbits have a wide age range and are nearly exclusively female or female spayed. Most mammary tumors are carcinomas. These may occur together with non-neoplastic or benign mammary lesions. Frequent microscopic findings are lipid droplets in tumor cells, secretory activity and microscopic heterogeneity. Since carcinomas are often negative for estrogen and progesterone receptors (ER-α/PR), modulation of receptor function will unlikely be beneficial for most rabbits. ER-α and PR status may have prognostic significance, since ER-α- or PR-negative tumors have significantly higher mitotic rates than ER-α- or PR-positive tumors. The frequent secretory activity of rabbit mammary tumors may suggest an influence of prolactin on tumorigenesis. Available data contribute to comparative pathology and are the basis for future molecular studies into the identification of additional prognostic factors and novel therapeutic options. They will also reveal the suitability of the rabbit as a model for certain types of breast cancer in women. Full article

Canine mast cell tumours (MCTs) present a wide variety of challenging clinical behaviours in terms of predicting the prognosis and choosing appropriate treatment. This study investigated the frequency, risk, and prognostic factors of MCTs in dogs admitted to a single veterinary teaching hospital (VTH). Breed, age, sex, and sexual status in ninety-eight dogs with MCTs (MCT-group) were compared with a control group of 13,077 dogs (VTH-group) obtained from the VTH clinical database from January 2010 to January 2016. Within the MCT-group, signalment, location, size, mass number, ulceration, histopathological grading, presence of lymph node, or distant metastases were compared with each other and with the outcome. Boxers (OR 7.2), American Pit Bull Terriers (OR 5.4), French Bulldogs (OR 4.4) and Labrador Retrievers (OR 2.6) were overrepresented. The MCT-group was significantly older than the VTH-group (p < 0.0001). In comparison with the VTH group, in the MCT-group neutered dogs (OR 2.1) and spayed females (OR 2.3) were predominant compared to intact dogs and intact females, respectively. Ulceration (OR 5.2) and lymph node metastasis (OR 7.1) occurred more frequently in larger MCTs. Both ulceration and MCTs > 3 cm were highly associated with lymph node metastasis (OR 24.8). Recurrence was associated with MCT-related death (OR 10.50, p = 0.0040), and the latter was associated with shorter survival times (p = 0.0115). Dogs with MCTs > 3 cm (p = 0.0040), lymph node metastasis (p = 0.0234), or elevated WHO stage (p = 0.0158) had shorter survival times. A significantly higher frequency of MCTs was found in specific breeds, and in older and neutered dogs. MCTs > 3 cm and lymph node or distant metastases were associated with shorter survival times. Full article

The incidence of canine mammary carcinoma varies with age, breed, and spay status, being among the main tumors appearing in intact female dogs. Thirty-six canine mammary carcinoma patients received injections of canine interferon-β (cIFN-β) and HSV-thymidine kinase/ganciclovir (HSV-tk/GCV) carrying lipoplexes, into the tumor bed, immediately after surgery. Next, they started periodic subcutaneous injections of lipoplexes carrying a human granulocyte-macrophage colony stimulating factor and interleukin-2 mixed with allogeneic mammary carcinoma extracts. This combined strategy was safe and well tolerated. In addition, only two out of 26 patients treated with complete surgery developed a local relapse, and 0 out of 29 stage II and III patients displayed distant metastases, suggesting both local and systemic antitumor activities. The most encouraging result was the long survival times: 22 > 1 year (where 13 > 2 and 4 > 3 years), while maintaining a good quality of life. The preliminary results in five patients presenting with local disease, an additional HSV-tk/GCV plus cIFN-β gene treatment induced local antitumor activity, evidenced by four objective responses (one complete, three partial) and one stable disease. This successful outcome supports further studies to validate this approach not only for canine veterinary patients, but also for translation to human patients. Full article