Estimation of body weight using body measurements in female water buffaloes reared in southeastern Mexico.

Buffalo farming is an important livestock activity in Mexico. However, the low technological level of the farms makes it difficult to monitor the growth rates of the animals. The objectives of this study were to analyse the body measurements of 107 adult female Murrah buffaloes, to estimate the interrelationships between those measurements and body weight, and to develop equations to predict body weight (BW) using body measurements including withers at height (WH), rump height (RH), body height (BH), heart girth (HG), abdominal girth (AG), pelvic girth (PG), body length (BL), girth circumference (GC), diagonal body length (DBL), pelvic circumference (PC), and abdomen circumference (AC). The study was conducted on two commercial farms in southern Mexico. Pearson correlation and stepwise regression techniques were used for the data analysis. To find out the best regression models, we used model quality criteria such as coefficient of determination (R2), adjusted R2 (Adj.R2), root mean square error (RMSE), Mallow's Cp, Akaike's information criteria (AIC), Bayesian information criteria (BIC), and coefficient of variation (CV). Correlation results indicated that BW had a positive high correlation (P < 0.01) of all the measured traits. Model 4 (-780.56 + 311.76GC + 383.51DBL + 51.82PC + 47.65AC-106.78BL) was the best regression model with a higher R2 (0.87), Adj. R2 (0.86) smaller Cp (4.24), AIC (749.19), BIC (752.16), and RMSE (36.91). The current study suggests that GC, DBL, PC, AC, and BL might be used in combination to estimate BW of adult female Murrah buffaloes.

EVALUATION OF PELIBUEY LAMBS BORN TO MOTHERS PHENOTYPICALLY SEGREGATED ACCORDING TO RESISTANCE TO GASTROINTESTINAL NEMATODES IN THE HUMID TROPICS OF MEXICO.

The objective was to evaluate the effect of the resistance of ewes to gastrointestinal nematodes (GIN) on the parasitologic and productive performance of their lambs during preweaning and postweaning periods. Offspring from 44 Pelibuey ewes classified as resistant or susceptible to GIN were evaluated. During the preweaning period, birth weight (BW), live weight (LW) at 35 and 70 days of age, and live weight changes (LWC) were determined in 73 lambs. During the postweaning period, 20 lambs to susceptible or resistant ewes were evaluated. The lambs were challenged under natural GIN infections and artificial infection with L3 of Haemonchus contortus. The fecal egg count (FEC), hematocrit (HT), peripheral eosinophil count, plasma protein, LW, and LWC were determined. There were no differences among parameters evaluated during preweaning (P > 0.05). The type of lambing (single or multiple) affected the BW, LW, and LWC (P < 0.01). The sex (male) of the lamb had a positive effect on BW at 35 and 70 days of age (P < 0.05). After weaning, lambs of susceptible ewes showed higher FEC than resistant ewes (P < 0.05). The HT of lambs to resistant ewes was higher than those the susceptible group (P < 0.01). In conclusion, offspring of resistant ewes show low FEC compared with those susceptible during the postweaning stage.

Cluster Analysis of Dengue Morbidity and Mortality in Mexico from 2007 to 2020: Implications for the Probable Case Definition.

Dengue cases and deaths occur frequently in Mexico, although the trend is not uniform across the country. We performed a Spatio-temporal analysis of dengue cases and deaths in Mexico from 2007 to 2020, and clustered states according to whether there was a low, moderate, or high risk of dengue. A total of 501,600 confirmed dengue cases were registered from 2007 to 2020, with 378,122 cases classified as dengue fever (DF) and 123,478 cases classified as dengue hemorrhagic fever (DHF). For each confirmed case, there were 4.68 probable cases. There were 1,230 dengue deaths, with highest numbers reported in 2009, 2012, 2013, and 2019. The number of deaths had a significant correlation (P ≤ 0.01) with DF (r = 0.82), DHF (r = 0.94), and probable dengue cases (r = 0.84). States were clustered using Machine Learning technique according to select indices associated with dengue. Cluster 1 (low risk) primarily contained states in the northwest, northcentral, and east. Cluster 2 (moderate risk) includes states in the northeast. Cluster 3 (high risk) mostly contained coastal states in the southeast, southwest, and west. The generation of the clusters was supported by the Kruskal-Wallis test. A significant difference was found in the incidence, mortality rates, and case-fatality rates of dengue among the clusters (P ≤ 0.01). Notably, cluster 3 contributed 71.4% of the confirmed cases and 89.2% of the deaths. Public health and vector control strategies designed to mitigate the burden of dengue in Mexico should consider the states in cluster 3 as high priority areas.

Prevalence and Factors Associated with Ectoparasite Infestations in Dogs from the State of Tabasco, Mexico.

This study was carried out to identify the ectoparasites that infest owned dogs in the state of Tabasco, Mexico. In total, 1,302 dogs were sampled in the 5 ecological regions of Tabasco. The dog owners were surveyed to identify the factors associated with infestations. Ectoparasites were identified using taxonomic keys. Eleven species of ectoparasites were observed. General prevalence was 26.65%. Rhipicephalus sanguineus and Ctenocephalides felis were the most prevalent and abundant ectoparasites. The most important factors associated with ectoparasite infestations in the studied dogs were living outdoors, being a non-purebred, having short hair, being dark-haired, and having a body condition <3. Ectoparasite studies such as the one presented herein generate important information to create control programs focused on decreasing infestations in companion animals and thus the likelihood of zoonotic transmission of pathogens.

Identification of parasitic arthropods collected from domestic and wild animals in Yucatan, Mexico.

The morphological characterization of ectoparasites from domestic and wild animals is crucial to distinguish those that may be involved in the transmission of zoonotic pathogens. The objectives of this work were to identify parasitic arthropods collected from several hosts in Yucatan State, Mexico and to determine the prevalence of the parasite Trypanosoma cruzi in sylvatic specimens of Triatoma dimidiata. Morphological traits and scanning electron microscopy were used to confirm some parasitic identities. In total, 834 parasitic arthropods of various taxa were identified. Amblyomma americanum, Amblyomma maculatum, Amblyomma parvum, Dermacentor variabilis, and Rhipicephalus sanguineus were identified from dogs, horses, sheep, and deer. The flea Ctenocephalides felis was identified from dogs and the human flea, Pulex irritans was found on horses and sheep. The Neotropical deer ked Lipoptena mazamae was identified from brown brocket deer Mazama pandora. The chewing lice Chelopistes meleagridis, Menacanthus stramineus, Menopon gallinae, Myrsidea sp. and Lipeurus caponis were identified from poultry (Meleagris gallopavo and Gallus gallus). Other chewing lice, Tyranniphilopterus sp., Columbicola columbae, and Physconelloides eurysema were identified from wild birds Pachyramphus aglaiae, Patagioenas flavirostris and Zenaida asiatica, respectively. Trypanosoma cruzi was present in 52.5% of sylvatic adult T. dimidiata. Several of these findings represent new records of ectoparasites for Yucatan and new distribution areas in Mexico. The implications for human and animal health are discussed.

Dirofilaria immitis proteins recognized by antibodies from individuals living with microfilaremic dogs.

INTRODUCTION: Dirofilaria immitis is a nematode that affects human health in several countries of the world. This study was conducted to examine whether serum samples from the owners of microfilaremic dogs present immunoreactivity to parasite proteins. METHODOLOGY: Eight serum samples from the owners of microfilaremic dogs were examined. Total proteins were extracted from adult worms and 12% SDS-PAGE was performed. The gel was electroblotted to a nitrocellulose membrane, and a Western blot (WB) was performed. Reactive bands of 22, 33, 39, 49, and 63 kDa in WB were excised from the gel and analyzed by mass spectrometry (MS). RESULTS: The MS results showed the presence of 10 different proteins of D. immitis recognized by the human serum samples. CONCLUSIONS: These results indicate that in endemic areas of D. immitis, owners of infected dogs recognize specific proteins of the parasite, suggesting a possible infection.

Four Species of Under-reported Parasitic Arthropods in Mexico and their Potential Role as Vectors of Pathogens.

Numerous arthropod taxa are important in human and veterinary medicine. The salivary secretions and feces of arthropods can cause allergic reactions in host vertebrates or harbor pathogens. Also, bites can be a risk factor for secondary infections. Documenting the diversity of arthropods of medical and veterinary importance remains an important aspect of disease control and prevention. We provide new records of ectoparasitic arthropods from Mexico that are of potential medical or veterinary relevance. Scanning electron microscopy along with amplification and sequencing of a fragment of the mitochondrial gene (16S rRNA) was used to confirm some species identities. We report the cat louse Felicola subrostratus from cats and the chewing louse Heterodoxus spiniger from dogs, which are common ectoparasites but largely not reported in Mexico. The chigger Eutrombicula alfreddugesi is common on wild lizards (Squamata). For the first time, E. alfreddugesi is reported on Hemidactylus frenatus (common house gecko). This reptile has a close relationship with humans and its chiggers can cause dermatitis (i.e., trombiculiasis) or transmit pathogens. In addition, the common bed bug Cimex lectularius is reported for the first time in the state of Yucatan, an atypical area for its natural distribution. Phylogenetic analysis revealed that Cimex lectularius from Yucatan is closely related to genetic sequences of Cimex lectularius from China. Knowing the regional distribution of arthropods allows the design and implementation of prevention strategies for those that have potential roles as reservoirs or vectors.

Rickettsia parkeri (Rickettsiales: Rickettsiaceae) detected in Amblyomma maculatum ticks collected on dogs in Tabasco, Mexico.

The present study was carried out to identify Rickettsia species with zoonotic potential in ticks collected from dogs in a rural area in Tabasco, Mexico. In total 197 Amblyomma maculatum ticks were collected from 40 domestic dogs. The collected specimens were pooled and subjected to DNA extraction. A fragment (380 bp) of citrate synthase gene (gltA) was amplified by polymerase chain reaction (PCR) using universal primers for Rickettsia. A second PCR was later performed to amplify a fragment (420 bp) of the outer membrane protein B gene (ompB). The PCR products were purified, sequenced and compared using the basic local alignment search tool (BLAST). Twenty out of 40 (50%) tick pools assayed were positive for rickettsial DNA using both primer pairs. The consensus sequence obtained from the ompB gene fragments showed 99.5-100% of identity with strains of Rickettsia parkeri. This study provides the first molecular evidence of the presence of R. parkeri in A. maculatum ticks infesting domestic dogs from southeastern Mexico. Close contact between dogs and humans should lead to consider the infection caused by this species of Rickettsia among the differential diagnoses for people of Tabasco, Mexico, who show acute febrile syndrome associated to inoculation eschar and have a clinical history of tick exposure.

Relationships among body condition score, FAMACHA© score and haematological parameters in Pelibuey ewes.

The objective of the present study was to determine the associations between the FAMACHA© score, body condition score (BCS) and several haematological parameters of Pelibuey ewes. In total, 52 clinically healthy Pelibuey ewes were evaluated in this study. A blood sample was collected from each animal to determine haematological variables. The BCS was evaluated on a scale of 1 to 5 and subsequently grouped into four categories: (1) < 1.5, (2) 2.0-2.5, (3) 3.0-3.5 and (4) > 4.0. The coloration of conjunctival mucosa was evaluated using the FAMACHA© system. The analysed haematological parameters were red blood cell (RBC) count, haemoglobin (HGB), haematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), red blood cell distribution width standard deviation (RDW-SD) and red blood cell distribution width coefficient of variation (RDW-CV). A descriptive statistical analysis was performed, and the Pearson correlation coefficients between variables were estimated. Haematological parameters were analysed with one-way analyses of variance, and the Tukey test was applied when significant differences were detected. The FAMACHA© score was only associated with MCHC (r = - 0.30, P < 0.05). The haematological parameters of RBC count, HCT, RDW-SD and RDW-CV statistically differed among BCS groups. The BCS was associated with RBC count, HCT, RDW-SD and RDW-CV, with r values ranging from 0.35 to 0.48. The haematological values were similar to those reported in ewes from Iran and Iraq. Hence, the optimization of the BCS calculation of Pelibuey ewes can generate association tables with haematological parameters to aid in the sanitary and feeding management of sheep.

Ovarian dynamics of buffalo (Bubalus bubalis) synchronized with different hormonal protocols.

The study evaluates the effect of three hormonal protocols on ovarian dynamics and progesterone (P4) secretion of buffalo (Bubalus bubalis). Twenty-nine pluriparous Murrah buffaloes were used. The protocols were as follows: OVSYNCH (n = 10): 100 µg of gonadorelin (day 0), 500 µg of cloprostenol (day 7), and 100 µg of gonadorelin (day 9). CIDR+EB (intravaginal device (CIDR®) + estradiol benzoate; n = 10): CIDR plus 2 mg of EB (day 0), withdrew of CIDR, 500 µg of cloprostenol (day 7) and 1 mg of EB (day 8). CIDR+eCG (n = 9): CIDR plus 2 mg of EB (day 0), withdrew of CIDR, 500 µg of cloprostenol and 400 IU of eCG (day 7). Follicles were counted with an ultrasound and measured at 0, 24, and 54 h. The maximum follicle diameter and ovulation were evaluated at 70, 80, and 94 h after CIDR withdrew. Estrous was detected per 1 h three times daily. Blood samples were collected on days 0, 7, 10, 15, and 22 to determine P4 concentration. In CIDR+EB protocol, 50% of buffaloes presented estrous, at 69.6 h. All buffaloes ovulated. CIDR+eCG group had the shortest (69 h) ovulation time. No treatment differences for follicular population, maximum follicle diameter, and P4 concentration on days 7 and 10 (P > 0.05) were found. The P4 concentration in OVSYNCH and CIDR+eCG protocols were > 1 ng/ml, on days 15 and 22 (P < 0.05). There was no difference in ovarian activity; however, the P4 secretion was normal in the OVSYNCH and CIDR+eCG protocols compared to the CIDR+EB protocol.

Entomological and virological surveillance for dengue virus in churches in Merida, Mexico.

This study was designed to assess whether churches in endemic dengue districts in Merida, Mexico provide suitable breeding habitats for mosquitoes and are potential sites for dengue virus (DENV) transmission. Churches were inspected for immature and adult mosquitoes once every week from November 2015 to October 2016. A total of 10,997 immatures of five species were collected. The most abundant species were Aedes aegypti (6,051) and Culex quinquefasciatus (3,018). The most common source of immature Ae. aegypti were buckets followed by disposable containers. Adult collections yielded 21,226 mosquitoes of nine species. The most common species were Cx. quinquefasciatus (15,215) and Ae. aegypti (3,902). Aedes aegypti were found all year long. Female Ae. aegypti (1,380) were sorted into pools (166) and assayed for flavivirus RNA by RT-PCR and Sanger sequencing. Two pools were positive for DENV (DENV-1 and 2). In conclusion, we demonstrated that some churches in Merida are infested with mosquitoes all year long and they potentially serve as sites for DENV transmission and should therefore be considered for inclusion in mosquito and arboviruses control and surveillance efforts.

Complete Genome Sequence of Houston Virus, a Newly Discovered Mosquito-Specific Virus Isolated from Culex quinquefasciatus in Mexico.

We fully sequenced the genome of Houston virus, a recently discovered mosquito-associated virus belonging to the newly established family Mesoniviridae. The isolate was recovered from Culex quinquefasciatus in southern Mexico, which shows that the geographic range of Houston virus is not restricted to the United States in North America.

Molecular detection of Dirofilaria immitis in dogs and mosquitoes in Tabasco, Mexico.

BACKGROUND & OBJECTIVES: Dirofilaria immitis is a filarial nematode that causes heartworm disease in domestic as well as wild canines and felines; and cutaneous or pulmonary infections in humans. The purpose of the study was to estimate the prevalence of D. immitis in domestic dogs in Tabasco, Mexico and to assay mosquitoes temporally and spatially associated with dogs for evidence of infection. METHODS: Blood was collected from 1050 dogs in 1039 houses during a random household survey performed in 2016 and 2017. Genomic DNA was extracted and assayed by polymerase chain reaction (PCR) using pan-filarial primers and various species-specific primers. Dog owners were interviewed using a structured questionnaire designed to collect information on factors that may impact the occurrence of filarial infection. The association between canine dirofilariasis prevalence and factors likely to impact infection was determined by univariate logistic regression analysis, followed by multivariate binomial logistic regression analysis. Indoor and outdoor resting mosquitoes were collected from houses by manual aspiration. Mosquitoes were identified according to species, homogenized and tested by PCR for filarial nematodes. RESULTS: A total of 84 (8%) dogs were positive for D. immitis DNA, while 3 (0.3%) dogs contained Acanthocheilonema reconditum DNA. Several factors were significantly associated with D. immitis infection. For example, dogs that lived <100 m from a large source of open standing water were significantly more likely (p = 0.002) to become infected with D. immitis than other dogs. Additionally, dogs with infrequent or no anthelmintic treatment were significantly more likely (p = 0.0) to become infected than dogs that were regularly treated. The entomologic investigation yielded 2618 female mosquitoes from 14 species. Four pools of Culex quinquefasciatus were positive for D. immitis DNA and the minimum infection rate, calculated as the number of positive pools per 1000 mosquitoes tested, was 2.9. INTERPRETATION & CONCLUSION: The study identified several factors positively associated with an increased risk of D. immitis infection in domestic dogs in Tabasco and provides evidence that Cx. quinquefasciatus is potentially an important vector in this region. This information can be used by local veterinarians and dog owners to reduce the burden of D. immitis on canine health.

Study of Aedes aegypti population with emphasis on the gonotrophic cycle length and identification of arboviruses: implications for vector management in cemeteries.

Aedes aegypti is the vector of the arboviruses causing dengue, chikungunya and zika infections in Mexico. However, its presence in public places has not been fully evaluated. In a cemetery from Merida, Yucatan, Mexico, the productivity of Ae. aegypti, the gonotrophic cycle, and the presence of Ae. aegypti females infected with arboviruses were evaluated. Immature and adult mosquitoes were inspected every two months between April 2016 to June 2017. For the gonotrophic cycle length, the daily pattern of total and parous female ratio was registered and was analyzed using time series analysis. Ae. aegypti females were sorted into pools and assayed for flavivirus RNA by RT-PCR and Sanger sequencing. Aedes aegypti immatures represented 82.86% (8,627/10,411) of the collection. In total, 1,648 Ae. aegypti females were sorted into 166 pools. Two pools were positive; one for dengue virus (DENV-1) and the other for zika virus (ZIKV). The phylogenetic analysis revealed that the DENV-1 is more closely related to isolates from Brazil. While ZIKV is more closely related to the Asian lineage, which were isolates from Guatemala and Mexico. We report some evidence of vertical transmission of DENV-1 in nulliparous females of Ae. aegypti. The gonotrophic cycle was four and three days in the rainy and dry season, respectively. The cemetery of Merida is an important focus of Ae. aegypti proliferation, and these environments may play a role in arboviruses transmission; probably limiting the efficacy of attempts to suppress the presence of mosquitoes in domestic environments.

Hematologic RIs for healthy water buffaloes (Bubalus bubalis) in southern Mexico.

BACKGROUND: Baseline hematologic data are used by veterinarians and wildlife biologists to perform health assessments on target animal species. Hematologic measurements are influenced by various factors including geography. Baseline hematologic RIs have been established for domestic water buffaloes (Bubalus bubalis) from various countries in the Eastern Hemisphere, but these data are not readily available for the Western Hemisphere. OBJECTIVE: The aim of this study was to determine hematologic values for domestic water buffaloes from several commercial farms in southern Mexico. METHODS: Blood was collected from 126 healthy, postlactating females (3 to 10 years old) from the Murrah breed, and 10 hematologic variables were measured. RESULTS: Means, SDs, RIs, medians (MED), median absolute deviations (MAD), and other statistics were calculated for each hematologic variable. The MED (and MAD) for each variable are as follows: RBC count, 7.6 (1.1) × 1012 /L; hemoglobin, 116.0 (13.3) g/L; PCV, 41.5 (7.6) %; MCV, 56.8 (7.0) fL; MCH, 14.6 (1.6) pg; MCHC, 250.0 (35.6) g/L; RDW (SD), 29.7 (5.5) fL; RDW (CV), 18.2 (1.4) %; reticulocytes, 0.0 (0.0) %, and WBC count, 12.4 (1.3) × 109 /L. These values were compared to those previously reported for water buffaloes from several countries in the Eastern Hemisphere and, on most occasions, they differed significantly. CONCLUSIONS: Our data can be used by veterinarians and other personnel involved in buffalo production in Mexico during medical evaluations.

Study of gastrointestinal parasites in water buffalo (Bubalus bubalis) reared under Mexican humid tropical conditions.

The objective was to determine the frequency of gastrointestinal parasites (GP) genera affecting water buffalo (Bubalus bubalis) reared under humid tropical conditions of Mexico. Three hundred eighty-three Munrah breed water buffalo were included, 251 adult females and 132 calves. Feces were directly collected form the rectum of the animals and processed by the McMaster technique. Coprocultures were made to identify the genera of the nematodes. The frequency of GP in B. bubalis was 42%, independently of their age, 60% of calves resulted parasitized. Age had a strong association with the presence of GP (Xi2 = 77.4014, d.f. = 1, p = 0.001). The family Trichostrongylidae was found in both age groups. The genera identified were Strongyloides sp. (47.2%), Cooperia sp. (33.9%), and Haemonchus sp. (10.4%), as well as Eimeria sp., Moniezia sp., Trichuris sp., and Strongyloides sp. The highest parasite burden corresponded to the genus Strongyloides sp. with 1108.9 EPG. There is a need to carry out further studies in order to know the prevalence and incidence of nematode affecting to B. bubalis as an introduced animal species to Mexican tropics.

Chikungunya Virus in Febrile Humans and Aedes aegypti Mosquitoes, Yucatan, Mexico.

Chikungunya virus (CHIKV) was isolated from 12 febrile humans in Yucatan, Mexico, in 2015. One patient was co-infected with dengue virus type 1. Two additional CHIKV isolates were obtained from Aedes aegypti mosquitoes collected in the homes of patients. Phylogenetic analysis showed that the CHIKV isolates belong to the Asian lineage.

Prevalence of gastrointestinal parasites in domestic dogs in Tabasco, southeastern Mexico.

The overall goal of this study was to estimate the prevalence of gastrointestinal (GI) parasites in dogs in the city of Villahermosa in Tabasco, Mexico. The study population consisted of 302 owned dogs that had limited access to public areas. A fecal sample was collected from each animal and examined for GI parasites by conventional macroscopic analysis and centrifugal flotation. Fecal samples from 80 (26.5%) dogs contained GI parasites. Of these, 58 (19.2%) were positive for helminths and 22 (7.3%) were positive for protozoan parasites. At least seven parasitic species were identified. The most common parasite was Ancylostoma caninum which was detected in 48 (15.9%) dogs. Other parasites detected on multiple occasions were Cystoisospora spp. (n = 19), Toxocara canis (n = 7) and Giardia spp. (n = 3). Three additional parasites, Dipylidium caninum, Trichuris vulpis and Uncinaria spp., were each detected in a single dog. No mixed parasitic infections were identified. In summary, we report a moderately high prevalence of GI parasites in owned dogs in Villahermosa, Tabasco. Several parasitic species identified in this study are recognized zoonotic pathogens which illustrates the important need to routinely monitor and treat dogs that live in close proximity to humans for parasitic infections.

Prevalence of gastrointestinal parasites in domestic dogs in Tabasco, southeastern Mexico / Prevalência de parasitas gastrointestinais em cães domésticos em Tabasco, sudeste do México

Abstract The overall goal of this study was to estimate the prevalence of gastrointestinal (GI) parasites in dogs in the city of Villahermosa in Tabasco, Mexico. The study population consisted of 302 owned dogs that had limited access to public areas. A fecal sample was collected from each animal and examined for GI parasites by conventional macroscopic analysis and centrifugal flotation. Fecal samples from 80 (26.5%) dogs contained GI parasites. Of these, 58 (19.2%) were positive for helminths and 22 (7.3%) were positive for protozoan parasites. At least seven parasitic species were identified. The most common parasite was Ancylostoma caninum which was detected in 48 (15.9%) dogs. Other parasites detected on multiple occasions were Cystoisospora spp. (n = 19), Toxocara canis (n = 7) and Giardia spp. (n = 3). Three additional parasites, Dipylidium caninum, Trichuris vulpis and Uncinaria spp., were each detected in a single dog. No mixed parasitic infections were identified. In summary, we report a moderately high prevalence of GI parasites in owned dogs in Villahermosa, Tabasco. Several parasitic species identified in this study are recognized zoonotic pathogens which illustrates the important need to routinely monitor and treat dogs that live in close proximity to humans for parasitic infections.

Resumo O objetivo geral deste estudo foi estimar a prevalência de parasitas gastrointestinais (GI) em cães na cidade de Vilhahermosa, em Tabasco, México. A população estudada consistiu de 302 cães com donos, com acesso limitado a áreas públicas. Uma amostra fecal de cada animal foi coletada e examinada para parasitas GI por análise macroscópica convencional e centrífugo-flutuação. Amostras fecais de 80 (26,5%) cães apresentaram parasitas GI. Destes, 58 (19,2%) foram positivos para helmintos e 22 (7,3%) foram positivos para protozoários. Pelo menos 7 espécies parasitas foram identificadas. O parasita mais comum foi Ancylostoma caninum, detectado em 48 (15,9%) cães. Outros parasitas detectados em diversas ocasiões foram Cystoisospora spp. (n = 19), Toxocara canis (n = 7) e Giardia spp. (n=3). Adicionalmente, três parasitas foram detectados em apenas um cão – Dipylidium caninum, Trichuris vulpis e Uncinaria spp. Nenhuma infecção mista foi observada. Em resumo, nós identificamos neste trabalho uma prevalência moderadamente alta de parasitas GI em cães com donos, em Villahermosa, Tabasco. Várias espécies de parasitas identificados são reconhecidamente patógenos zoonóticos, o que indica a necessidade de monitorar rotineiramente e tratar infecções parasitárias em cães que vivem em proximidade a populações humanas.