Stray dogs are one of the main reservoirs of intestinal parasitic infections and some have zoonotic potential. An epidemiological survey was carried out between September 2017 and May 2018 in Mexicali Valley, this area sacrifices around 92,470 head of cattle monthly, which represents 27% of the national slaughter and has 71,307 hectares for crops. In this period the Municipal Animal Control Center during their routine visits to the Mexicali Valley captured 103 dogs. All the dogs were evaluated using copromicroscopic techniques to detect intestinal parasites. The general frequency of parasitic infections was 28.15% (29/103), the most frequent parasite being Dipylidium caninum 16.50% (17/103), followed by Taenia spp. 6.79% (7/103), Taenia hydatigena 2.91% (3/103), Taenia serialis 0.97% (1/103), Taenia pisiformis (0.97%), Toxocara canis 3.88% (4/103), Toxascaris leonina 1.94% (2/103), and Cystoisospora spp. 1.94% (2/103). No significant statistical associations were found between parasitic infections and the studied variables (sex, age, and size) however; there was a significant statistical association with the capture area. Most of the parasites found in this survey have potential to affect the human population and animal production.

In many rural regions of Mexico, beekeeping is an important socioeconomic activity which is currently facing various health issues, being the main one the presence of infectious diseases. The aim of our study was to optimize a duplex Eva Green RT-PCR assay along with melting-curve analysis to detect and differentiate Nosema apis from Nosema ceranae infection in Apis mellifera. At four locations in Northwest Mexico 765 samples from 76 apiaries were tested using a RT-PCR and melting-curve analysis. Infection was detected in all the four geographical regions under study. Overall, 87.32% samples resulted positive for N. apis, 12.68% for N. ceranae and 10.20% resulted co-infected with both microsporidians. The Mexicali valley had the highest prevalence of N. apis with 56.68% positive apiaries, while in Ensenada the lowest prevalence was found with 7.89% positive apiaries. The highest prevalence of N. ceranae was detected in Mexicali (15.79%), while Tijuana and San Luis Rio Colorado showed the lowest prevalence with 1.32%, respectively. Our work indicates a wide spread of nosemosis in all the four geographical regions with a marked dominion of N. apis. The RT-PCR assay resulted highly specific and accurate for the detection of N. apis and N. ceranae and could provide a rapid and accurate diagnostic tool for the simultaneous detection and discrimination of both microsporidians. It can also be used for clinical diagnostics and disease surveillance and to evaluate the effectiveness of the measures for control and prevention of nosemosis in the Northwest corner of Mexico.

Ehrlichia and Anaplasma are obligate intracellular, gram-negative bacteria with tropism for hematopoietic cells, especially leukocytes and platelets. There are several Ehrlichia species that infect dogs. Ehrlichia canis is transmitted by Rhipicephalus sanguineus and replicates within monocytes and macrophages, leading to canine monocytic ehrlichiosis, a disease of worldwide distribution. The clinical signs are varied and non-specific. Anaplasma has two species that infect dogs, Anaplasma phagocytophilum and Anaplasma platys, the second also transmitted by Rhipicephalus sanguineus. This study aimed to evaluate the epidemiology and hematologic changes associated with the presence of Ehrlichia spp. and Anaplasma spp. coinfection in dogs from Baja California. Complete hematological analysis, examination of buffy coat smears, and ELISA tests were performed on blood samples from three veterinary diagnostic laboratories from Mexicali and Tijuana cities in Baja California, Mexico. A total of 5,469 dog samples were analyzed. The overall prevalence of Ehrlichia spp., was 4.79%, with a distribution of 6.3% in Mexicali (OR: 2.39 CI: 1.69-3.17) and 2.5% in Tijuana. The peak of infection was found in September. Contact with other dogs and tick infestation were the risk factors associated with infection (P < 0.05). There was 96% co-infection only in Tijuana and 0% in Mexicali. Anemia, thrombocytopenia, and hyperproteinemia are associated with Ehrlichia spp., and Ehrlichia/Anaplasma infection. In view of the foregoing, we have to maintain epidemiologic vigilance, as well as look further into the ticks present in the state and the possibility of transmission of unusual pathogens.

Cutaneous neoplasia is among the most common illnesses in dogs and can pose significant risks. Accurate morphological diagnosis of these conditions is vital for effective treatment and management. In this retrospective study, a total of 3746 canine skin biopsies were submitted to a veterinary reference diagnostic laboratory and evaluated using histopathology. The variables assessed included age, sex, breed, lesion, location, and histopathological diagnosis. Non-neoplastic lesions accounted for 61% of all analyzed samples, while neoplastic tumors accounted for 39%. When looking at age, dogs ranging 3–6 years and 7–9 years had at least six times higher risk of developing malignant neoplasia compared to those aged 0–2 years. Among the malignant neoplasms, mast cell tumors, hemangiosarcoma, and squamous cell carcinoma were the most observed, representing 30%, 18%, and 12% of cases, respectively. The breeds most frequently affected by malignant neoplasms included Pit Bull Terriers, Boxers, and mixed breeds, all of which comprised the majority of mast cell tumor cases at 50.54%. These findings are novel in this field and may assist small animal veterinarians in making preliminary diagnoses, while also helping pet owners understand the importance of skin cancer and its early detection.

Studies worldwide report cutaneous neoplasms in dogs; however, data in the arid regions of Mexico remain scarce. Here we report the main malignant cutaneous neoplasms diagnosed by fine needle aspiration cytology (FNAC), and describe the associations with age, sex and breed in Mexicali. Neoplastic lesions accounted for 25.52% (698/2735) of the cases, of which 56.59% (395/698) were malignant. The highest prevalence was observed in dogs aged 9–12 years (n = 193), intact males (n = 162), and mixed-breed dogs (n = 247). Round cell neoplasms (n = 309), including lymphoma, transmissible venereal tumors (TVT), and mast cell tumors (MCT), were the most common cell lineage. Using dogs aged 0–4 years as the reference group, dogs aged 9–12 years had 0.241 times the odds of developing malignant neoplasms (95% CI: 0.141–0.415, p = 0.0025). Using neutered males as the reference group, intact females showed 2.499 times the odds of developing malignant neoplasms (95% CI: 1.462–4.271, p = 0.0042). Compared to mixed-breed dogs, Schnauzers (OR = 0.161) showed significantly lower odds of malignancy (95% CI: 0.082–0.317, p = 0.0004), while Pitbull Terriers had 1.748 times more chance of present malignant neoplasia (95% CI: 1.014–3.013, p < 0.0001). This study provides significant epidemiological evidence on canine cutaneous neoplasms in an arid region of Mexico, identifying key risk factors and distribution patterns that can guide preventive, diagnostic, and therapeutic strategies tailored to regional characteristics.