Neoplastic and non-neoplastic diseases associated with feline leukaemia virus (FeLV) in cats in southern Brazil.

The objective of this study was to categorise diseases associated with FeLV infection in cats. A total of 154 cats were submitted to necropsy, histopathology exam and anti-FeLV immunohistochemistry (IHC), and 83 (50.9 %) were IHC FeLV-positive. The cats age means of 4.1 years, including 3.6 % kittens, 34.9 % junior, 37.4 % prime, 18.1 % mature, 2.4 % senior, 3.6 % unknown age. Neoplastic diseases were most prevalent with leukaemia and lymphoma being most predominant, followed by viral diseases, bacterial, trauma, degenerative, intoxications, parasitic, malformation and others. FeLV+ cats were 5.73 times more likely to be diagnosed with neoplasms than other diseases. The odds ratio (OR) of FeLV+ cats developing leukaemia (OR = 7.75) and lymphoma (OR = 6.75) was higher than other neoplasms. FeLV infection was more prevalent in the mixed breed, junior to prime, male, with neoplastic diseases, including leukaemia and lymphoma. Therefore, understanding the diseases associated with FeLV is of paramount importance in Brazil due to its high prevalence, and it may encourage the implementation of prophylactic measures to reduce its dissemination.

Identification of Anaplasma marginale, Babesia bovis and Babesia bigemina resistance alleles in Crioulo Lageano cattle using PCR-SBT and BoLA-DRB3 gene sequencing.

Introduction: The BoLA-DRB3 gene in cattle is associated with tolerance to several infectious diseases, such as neosporosis, dermatophilosis, leukosis, and mastitis. Methods: This study used PCR-SBT and BoLA-DRB3 gene sequencing to determine the association between the presence or absence of Anaplasma marginale, Babesia bovis, and Babesia bigemina infections in 208 Crioulo Lageano cattle and alleles present in the population. The chi-square test and odds ratio analysis were employed to establish the association. Results: Of the BoLA-DRB3 gene alleles present in the population, two alleles were significantly associated with resistance to A. marginale infections: BoLA-DRB3001:01 (p < 0.001; OR = 0.224), which had a frequency of 7.93%, and BoLA-DRB3024:06 (p = 0.007; OR < 0.00001), which had a frequency of 0.72%. Regarding B. bovis infection, the BoLA-DRB3*011:01 allele (p = 0.002; OR = 0.271) had a frequency of 6% in the population and was associated with resistance to the infection. None of the alleles was associated with resistance to infection by B. bigemina. Discussion: The Crioulo Lageano breed has alleles that may confer resistance against infection by A. marginale and B. bovis.

Progressive and regressive infection with feline leukemia virus (FeLV) in cats in southern Brazil: Prevalence, risk factors associated, clinical and hematologic alterations.

Enzyme-linked immunosorbent assay (ELISA) for viral antigen is commonly used for the diagnosis of progressive feline leukemia virus (FeLV) infection but is not able to determine the true prevalence of infection when used as the sole test. Additional testing to detect proviral DNA will identify regressive (antigen negative) FeLV infections as well as progressive infections. Therefore, this study aimed to determine the prevalence of progressive and regressive FeLV infection, outcome-associated factors, and hematologic changes. A cross-sectional study was performed on 384 cats selected from routine hospital care. Blood samples were subjected to complete blood count, ELISA for FeLV antigen and FIV antibody, and nested PCR amplifying the U3- LTR region and gag gene, which are conserved in most exogenous FeLV. The prevalence of FeLV infection was 45.6% (CI95% 40.6-50.6%). The prevalence of progressive infection (FeLV+P) was 34.4% (CI95% 29.6-39.1%), that of regressive infection (FeLV+R) was 10.4% (CI95% 7.4-13.4%), for discordant but positive results 0.8% (CI95% 0.75-0.84%), for FeLV+P coinfected with FIV 2.6% (CI95% 1.2-4.0%), and FeLV+R coinfected with FIV 1.5% (CI95% 0.3-2.7%). Male cats were three times more likely to be in the FeLV+P group. Cats coinfected with FIV were 4.8 times more likely to belong to the FeLV+R group. In the FeLV+P group, the main clinical changes were lymphoma (38.5%), anemia (24.4%), leukemia (17.9%), concomitant infections (15.4%), and feline chronic gingivostomatitis - FCGS (3.8%). In the FeLV+R group, the main clinical signs were anemia (45.4%), leukemia (18.2%), concomitant infections (18.2%), lymphoma (9.1%), and FCGS (9.1%). Cats in the FeLV+P and FeLV+R groups showed mainly thrombocytopenia (56.6% and 38.2%), non-regenerative anemia (32.8% and 23.5%), and lymphopenia (33.6% and 20.6%). Hemoglobin concentration, packed cell volume (PCV), platelet count, lymphocytes, and eosinophils in the FeLV+P and FeLV+R groups had lower medians than the control group (FeLV/FIV-uninfected, healthy). Erythrocyte and eosinophil counts were statistically different among the three groups, with the medians of the FeLV+P and FeLV+R groups being lower than those of the control group. In addition, the median PCV and band neutrophil counts were higher in FeLV+P than in FeLV+R. Our results show a high prevalence of FeLV, different factors associated with the course of infection, and more frequent and severe hematologic changes in progressive infections compared with regressive infections.

Prevalence of natural infection by Trypanosoma evansi in Crioula LAGEANA cattle.

Cattle trypanosomiasis negatively impacts animal husbandry due to high morbidity, productivity losses, and mortality rates. Knowledge regarding Trypanosoma evansi infections in locally adapted breeds remains limited. Some cattle breeds exhibit trypanotolerance, requiring the determination of prevalence, as well as related tolerance and resistance characteristics, for disease control programs. This study aimed to determine T. evansi prevalence in Crioula Lageana cattle and associate clinical, hematological, and biochemical aspects with the infection to further research on tolerance in this population. Blood samples from 310 Crioula Lageana cattle were tested using Polymerase Chain Reaction (PCR) and Indirect Immunofluorescence Reaction (IIFR). T. evansi prevalence was 8% (24/310) using PCR and 4% (11/310) using IIFR. Positive animals showed increased ruminal movements, elevated eosinophil counts, and reduced monocyte numbers, but both latter within the reference range for the species. Albumin concentrations were low in positive cases and remained below the reference range limit for both groups. However, triglycerides exceeded the physiological range for the species in both positive and negative groups. Increased gamma-glutamyltransferase (GGT) activity was observed in positive animals. In conclusion, Crioula Lageana cattle exhibited enzootic instability with a low T. evansi infection prevalence when assessed using PCR and IIFR techniques. Furthermore, the animals did not display clinical, hematological, or biochemical alterations attributable to the presence of hemoparasites.

Prevalence and Risk Factors Associated With Natural Infection by Trypanosoma evansi in Campeiro Horses.

Campeiro horse is a breed locally adapted to the Santa Catarina plateau region and its main characteristic is the gait, it is known as "Marchador das Araucárias." It is a breed considered in danger of extinction, being fundamental the search for the preservation of this important genetic resource. Surra, caused by the protozoan Trypanosoma evansi, is among the diseases that affect horses. However, there are no data on the prevalence of infection in Campeiro horses. This study aimed to determine the prevalence of T. evansi in Campeiro horses, correlate hematology and serum biochemistry, and identify possible risk factors. Blood samples were collected by venipuncture of 214 Campeiro horses, 50 males and 164 females, aged between 3 months and 27 years, from 16 properties located in the States of Santa Catarina, Rio Grande do Sul, and Paraná. An epidemiological questionnaire was carried out with the owners to analyze the associated risk factors. The blood samples were submitted to polymerase chain reaction, immunofluorescence antibody test, complete blood count, and serum biochemistry. The prevalence was 14% of positive animals by polymerase chain reaction and 59% by immunofluorescence antibody test . There was an increase in hematocrit, and in the number of basophils, a decrease in plasmatic fibrinogen, and in the enzymatic activity of alanine aminotransferase, aspartate aminotransferase, and urea, and an increase in creatine phosphokinase and creatinine in positive animals, which is possibly unrelated to the infection. The data obtained through the epidemiological questionnaires showed no difference. Therefore, T. evansi is present in the South of Brazil, with a high prevalence in Campeiro horses.

Phylogenetic identification of feline leukemia virus A and B in cats with progressive infection developing into lymphoma and leukemia.

To date, only a few studies have examined the impacts of feline leukemia virus (FeLV) subgroups on disease development in spontaneously infected cats. The present study identified FeLV-A and FeLV-B subgroups in cats with lymphoma and leukemia and explored the phylogenetic relationships of env sequences. Twenty-six cats with lymphoma (n=16) or leukemia (n=10) were selected. FeLV p27 antigen positivity was determined using ELISA, and proviral DNA in blood samples was detected using nested PCR. Positive animals in both tests were classified as cases of FeLV progressive infection and subjected to a second nested PCR for env amplification and subgroup determination. Six samples of FeLV-A and five samples of FeLV-B were sequenced using the Sanger method, and the results were used to build a phylogenetic tree and estimate evolutionary divergence. Among cats with lymphoma, 68.8% carried FeLV-AB and 31.2% FeLV-A. Among cats with leukemia, 70% carried FeLV-AB and 30% FeLV-A. Regarding cat characteristics, 50% were young, 30.8% young adults, and 19.2% adults; 88.5% were mixed-breed and 11.5% pure breed; and 42.3% were males and 57.7% were females. Among lymphomas, 62.5% were mediastinal, 31.3% multicentric, and 6.3% extranodal. Regarding histological classification, lymphoblastic and small non-cleaved-cell lymphomas were the most frequently detected. Among leukemia cases, 30% were acute lymphoid, 30% chronic myeloid, and 40% acute myeloid. Phylogenetic analysis showed that FeLV-A SC sequences were closely related to the Arena, Glasgow-1, and FeLV-FAIDS variants. Meanwhile, FeLV-B SC sequences were divergent from one another but similar to the endogenous FELV env gene (enFeLV). In conclusion, FeLV-AB is prevalent in cats with lymphoma and leukemia, highlighting the genetic diversity involved in the pathogenesis of these neoplasms in Brazil.

Prevalence and risk factors associated with Babesia bovis infection in Crioula Lageana cattle.

INTRODUCTION: Bovine babesiosis caused by the protozoan Babesia bovis is a worldwide disease and causes great economic damage to livestock. There are no studies on the epidemiology of this disease in native breeds such as Crioula Lageana cattle raised in the South of Brazil. METHODOLOGY: DNA samples from 311 animals were amplified by polymerase chain reaction (PCR) for the identification of the gene rap-1 (Rhoptry Associated Protein 1) from B. bovis. An epidemiological questionnaire was used to determine the risk factors associated with infection. RESULTS: The prevalence of B. bovis infection was 72% (224/311). Age and tick infestation affected infection. The factors associated with infection were the breeding objective (p = 0.042; CI = 0.746-0.995; OR = 0.861), contact of cattle with other animal species (p = 0.002; CI = 0.517-0.860; OR = 0.484), absence of tick control (p = < 0.001; CI = 0.074-0.480; OR = 0.188) and timing of tick treatment (p = 0.026; CI = 0.673-0.975; OR = 0.810), and these were considered to be factors that can protect against the disease. CONCLUSIONS: The Crioula Lageana cattle breed has near enzootic stability with regards to B. bovis infection.

Prevalence of Eimeria sp. in Broiler Poultry Houses with Positive and Negative Pressure Ventilation Systems in Southern Brazil.

Coccidiosis is an enteric disease caused by protozoa of the Eimeria genus and is of great economic relevance in industrial aviculture. The objective of this work was to determine the prevalence of Eimeria sp. in broiler poultry houses with positive (System 1) and negative (System 2) pressure ventilation and assess the associated factors. A transversal study was conducted using 8 random broiler chickens from 64 houses (n = 512) and macroscopic and histologic evaluation of the intestines, as well as PCR for Eimeria sp. The prevalence of Eimeria sp. was 90.6% (95% confidence interval [CI]: 97.8-83.5), with 93.8% (95% CI: 100-85.4) in System 1 and 87.5% (95% CI: 99.0-76.0) in System 2. The most prevalent species was Eimeria acervulina, and the most common combination was Eimeria acervulina, Eimeria maxima, and Eimeria tenella. System 2 and the negative Eimeria subgroup showed the best results for feed conversion and daily weight gain. By evaluating litter treatment, we found that quicklime reduced the risk of presence of Eimeria maxima and Eimeria tenella. In conclusion, Eimeria sp. had a high prevalence in both systems, with a predominance of mixed infections. System 2 and negative flocks showed the best zootechnical results.

Prevalencia de Eimeria sp. en casetas de pollo de engorde con presión positiva y presión negativa. La coccidiosis es una enfermedad entérica causada por protozoos del género Eimeria. Es una enfermedad de gran relevancia económica en la avicultura industrial. El objetivo de este trabajo fue determinar la prevalencia de Eimeria sp. en gallineros de engorde con ventilación de presión positiva (sistema 1) y negativa (sistema 2) y evaluar los factores asociados. Se realizó un estudio transversal con ocho pollos de engorde de 64 galpones (n = 512) con los cuales se realizó una evaluación macroscópica e histológica de los intestinos, así como PCR para Eimeria sp. La prevalencia de Eimeria sp. fue 90,6% (95% CI: 97,8-83,5), con 93,8% (95% CI: 100-85,4) en el sistema 1 y 87,5% (95% CI: 99,0-76,0) en el sistema 2. La especie más prevalente fue Eimeria acervulina, y la combinación más común fue Eimeria acervulina, Eimeria maxima y Eimeria tenella. El sistema 2 y el subgrupo Eimeria negativo mostraron los mejores resultados para la conversión alimenticia y el aumento de peso diario. Al evaluar el tratamiento de la cama, la cal viva redujo el riesgo de presencia de Eimeria maxima y Eimeria tenella. En conclusión, Eimeria sp. tuvo una alta prevalencia en ambos sistemas, con predominio de infecciones mixtas. El sistema 2 y los lotes negativos mostraron los mejores resultados zootécnicos.

High prevalence of Anaplasma marginale in the Crioula Lageana cattle.

INTRODUCTION: Bovine anaplasmosis is caused by the bacterium Anaplasma marginale; its transmission occurs through vectors such as ticks. Crioula Lageana is a native cattle breed from the South of Brazil used for beef production, with excellent meat quality. There are no studies of the epidemiology of this disease in Crioula Lageana even though tick damage is known to be frequent. METHODOLOGY: Blood samples were collected from 311 Crioula Lageana cattle and subjected to DNA extraction and polymerase chain reaction (PCR) using specific primers for the Major Surface Protein 5 (msp5) gene for the detection of the bovine anaplasmosis agent. The animals were classified according to the gender, the category and the presence or absence of ticks at the time of collection. The animal owners completed an epidemiological questionnaire to determine factors that might be associated with anaplasma infection. RESULTS: The prevalence of A. marginale was 79.9%. The following factors were found to be protective against infection: I) the breeding objectives (whether animals were destined for beef production and trade or solely for beef production), II) tick control rate; and III) pregnant and lactating cows and calves as the categories least affected by the hemoparasite. The main risk factor for hemoparasite acquisition was the use of organophosphates and avermectins as acaricides. CONCLUSIONS: Crioula Lageana cattle are in a situation of enzootic stability, with a high prevalence of A. marginale infection. The factors associated with the infection were: I) breeding objectives, II) tick control rate, III) the acaricides used, and IV) the most tick-parasitized categories of cattle.

Placas aurais em equinos mestiços de tração / Aural plaques in crossbred working horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was located in the median region of the quadrants, it was described in the region of the greatest location. To evaluate the histopathologic features, three equines that bearer typical lesions of aural plate were submitted to a biopsy.[...](AU)

Placas aurais em equinos mestiços de tração / Aural plaques in crossbred working horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was located in the median region of the quadrants, it was described in the region of the greatest location. To evaluate the histopathologic features, three equines that bearer typical lesions of aural plate were submitted to a biopsy.[...]

Aural Plaques in Crossbred Working Horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was locat

Aural Plaques in Crossbred Working Horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was locat

Aural Plaques in Crossbred Working Horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was locat

Aural Plaques in Crossbred Working Horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was locat

Aural Plaques in Crossbred Working Horses

Background: The aural plaque is a papillomatosis variant that occurs in the inner surface of the auricular pavilion of equine. The disease is associated with economic losses in the equine sector, since it reduces the commercial value of the severely affected animals. However, there are few studies evaluating the occurrence of aural plaques in different breeds and equine populations in Brazil and in other countries. The aim of the present study was to evaluate the frequency, clinical and histological characteristics of the aural plaques in working horses from Lages, SC, Brazil.Materials, Methods & Results: Seventy-three crossbreed equines were used, including 48 males and 25 females between 1 and 25 years old, and that were used as working horses (traction) in the urban perimeter in the city of Lages, SC. The findings related to breed, age, sex, presence or absence of compatible lesions with aural plaques, anatomical location and lesion characteristics were evaluated and annotated. The lesions were photographed and drawn on paper to determine the size and distribution in the ear and were reevaluated for a period of two months with an interval of 30 days between each evaluation. The number of aural plaques was determined by manual counting in each auricular pavilion, which were divided into four quadrants (left and right upper, right and left lower). When the plaque was locat