Dogs (Canis familiaris) as sentinels for determining the risk of occurrence of Rickettsia spp. and Anaplasma phagocytophilum in previously undiagnosed areas.

Determining the occurrence of Rickettsia spp. and Anaplasma phagocytophilum in municipalities with no case records is important to define surveillance strategies and is essential to reduce lethality in different regions. Therefore, an approach aimed at enhancing surveillance in municipalities with an unknown epidemiological situation was tested, according to the classification suggested by Resolution SMA/SES 07/01/16. Canine sera collected in the annual anti-rabies campaign were submitted to the indirect fluorescent antibody test for Rickettsia amblyommatis, R. belli, R. parkeri, R. rickettsii and A. phagocytophilum. Titers ≥1:64 and ≥1:320 were considered positive for Rickettsia spp. and A. phagocytophilum, respectively. For Rickettsia spp., 61.8% of dogs were seropositive, with 26% positive for more than one species, and 42.3% were seropositive for R. rickettsii. Dogs from the urban area presented 5.16 (CI 1.18; 7.69) times greater odds of seropositivity for R. parkeri (p = 0.037) and 3.39 (CI 1.04; 3.70) times greater odds for R. belli (p = 0.017). Considering the 1:40 cutoff point, 19.1% of dogs were reactive for A. phagocytophilum. Two (1%) dogs in rural areas were positive (titer 1:640). The results indicate all species ever tested in Lavras/MG, since the present study is the city's first report on the subject. According to classifications of the aforementioned Resolution, the results determine that the municipality of Lavras should be considered a "risk area" for Brazilian spotted fever(BSF). The methodology presented is efficient, straight forward to perform and inexpensive for diagnosing a risk situation for BSF and human granulocytic anaplasmosis. Moreover, its use can be applied throughout Brazil and other countries as a public health alert guideline.

Seroepidemiology of Toxoplasma gondii in Dairy Cows in Southeastern Brazil: Seropositive Cows on All Farms Investigated.

PURPOSE: This study aimed to estimate the prevalence and identify the risk factors associated with the higher in-herd T. gondii seroprevalence in dairy cows in 37 farms in southern Minas Gerais, Southeastern Brazil. METHODS: Serum samples from 1,105 dairy cows were subjected to an indirect fluorescence antibody test (IFAT 1:64) for anti-T. gondii IgG. The association existing between possible risk factors at the herd level and the seroprevalence were verified through Generalized Estimating Equation (GEE) multiple logistic regression models. RESULTS: Anti-T. gondii antibodies were observed in 31.4% of the cows (347; 95% CI= 28.7-34.2) and on 100% of the farms (37; 95% CI= 90.6-100.0%), indicating that all properties possessed at least one seropositive animal. For univariate analysis, herds with seroprevalence were categorized as greater and less than 30% as the outcome. The "breeding of Holstein Friesian cows" (p= 0.016, OR= 6.667, 95% CI= 1.500-29.628) and in an "intensive system" (p= 0.013, OR= 6.120, 95% CI= 1.394-26.876) increased the chance of the herd seroprevalence being greater than 30% by approximately six-fold. However, these variables did not exhibit a significant association (p >0.05) in the Generalized Estimating Equations (GEE) logistic regression model. CONCLUSIONS: The results demonstrate that T. gondii infection is widespread among dairy cows in the south of Minas Gerais, with a wide environmental dispersion of the parasite on farms in this region.

Economic evaluation and efficacy of strategic-selective treatment of gastrointestinal parasites in dairy calves.

In the Experimental Farm of the Universidade Federal de Lavras (EF-UFLA), state of Minas Gerais, Brazil, on their day of birth, female Holstein calves were randomly selected and placed into two groups containing fifteen animals each: Strategic-Selective Treatment (S-ST) or Conventional Treatment (CT). In the S-ST, calves were treated after coproparasitological examinations according to criteria established previously by the researchers. Calves in the CT were treated according to the opinion of the veterinarian of EF-UFLA. For statistical analysis, the frequency (%) of fecal samples with count of eggs per gram of feces (EPG) ≥300, count of oocysts per gram of feces (OoPG) ≥500 and fecal samples with count of cysts of Giardia spp. ≥1 were conducted. The overall average frequency of fecal samples with EPG ≥300, OoPG ≥500 and Giardia spp. cysts ≥1, respectively, was similar (p >0.05) between S-ST (20.3%; 17.3%; and 31.5%) and CT (26.4%; 23.9%; and 37.3%). The effective operational cost, per animal, in 12 months, was of R$ 784.58 (US$ 241.41) and R$ 83.90 (US$ 25.81) in S-ST and CT, respectively. The S-ST requires adjustments to be used as a technically efficient and economically viable alternative for the control of gastrointestinal parasitosis in female Holstein calves.

Economic evaluation and efficacy of strategic-selective treatment of gastrointestinal parasites in dairy calves / Avaliação econômica e eficácia do tratamento estratégico-seletivo de parasitos gastrointestinais em bezerras leiteiras

Abstract In the Experimental Farm of the Universidade Federal de Lavras (EF-UFLA), state of Minas Gerais, Brazil, on their day of birth, female Holstein calves were randomly selected and placed into two groups containing fifteen animals each: Strategic-Selective Treatment (S-ST) or Conventional Treatment (CT). In the S-ST, calves were treated after coproparasitological examinations according to criteria established previously by the researchers. Calves in the CT were treated according to the opinion of the veterinarian of EF-UFLA. For statistical analysis, the frequency (%) of fecal samples with count of eggs per gram of feces (EPG) ≥300, count of oocysts per gram of feces (OoPG) ≥500 and fecal samples with count of cysts of Giardia spp. ≥1 were conducted. The overall average frequency of fecal samples with EPG ≥300, OoPG ≥500 and Giardia spp. cysts ≥1, respectively, was similar (p >0.05) between S-ST (20.3%; 17.3%; and 31.5%) and CT (26.4%; 23.9%; and 37.3%). The effective operational cost, per animal, in 12 months, was of R$ 784.58 (US$ 241.41) and R$ 83.90 (US$ 25.81) in S-ST and CT, respectively. The S-ST requires adjustments to be used as a technically efficient and economically viable alternative for the control of gastrointestinal parasitosis in female Holstein calves.

Resumo Na Fazenda Experimental da Universidade Federal de Lavras (FE-UFLA), Minas Gerais, Brasil, no dia do nascimento, bezerras da raça holandesa foram sorteadas de forma aleatória para compor um dos dois grupos, formados por 15 animais cada: Tratamento Estratégico-Seletivo (TE-S) ou Tratamento Convencional (TC). No TE-S, as bezerras foram tratadas após exames coproparasitológicos de acordo com critérios previamente estabelecidos pelos pesquisadores. No TC, as bezerras foram tratadas conforme orientação do veterinário da FE-UFLA. Em ambos grupos, as bezerras foram monitoradas a cada 14 dias, do nascimento até os 12 meses de idade, por meio de exames coproparasitológicos. Para análise estatística, considerou-se a frequência (%) de amostras fecais com contagem de ovos por grama de fezes (OPG) ≥300, contagem de oocistos por grama de fezes (OoPG) ≥500, e amostras fecais com contagem de cistos de Giardia spp. ≥1. A frequência média global de amostras fecais com contagem de OPG ≥300, OoPG ≥500 e cistos de Giardia spp. ≥1, respectivamente, foi similar (p >0,05) entre TE-S (20,3%; 17,3%; e 31,5%) e TC (26,4%; 23,9%; e 37,3%). O custo operacional efetivo, por animal, em 12 meses, foi R$ 784,58 (US$ 241.40) e R$ 83,90 (US$ 25.81) para TE-S e TC, respectivamente. O TE-S necessita de ajustes para que possa ser indicado como uma alternativa, tecnicamente eficiente e economicamente viável, no controle das parasitoses gastrointestinais em bezerras leiteiras.

Seroepidemiology of Sarcocystis neurona, Toxoplasma gondii and Neospora spp. among horses in the south of the state of Minas Gerais, Brazil.

The present study used the indirect fluorescent antibody test (IFAT) to determine the seroprevalence of Sarcocystis neurona, Toxoplasma gondii and Neospora spp., and evaluated the variables associated with these infections among 506 apparently healthy horses, reared in the south of the state of Minas Gerais, Brazil. This study was conducted between April 2012 and October 2013. Among the horses, the true prevalence of S. neurona was 26% (95% CI: 22.0-30.4%), T. gondii 19.9% (95% CI: 15.5-24.8%) and Neospora spp. 23.9% (95% CI: 19.9-28.1%); and among the farms, 88.3% (95% CI: 74.4-91.6%), 71.6% (95% CI: 41-92.8%) and 85% (95% CI: 70.7-96.1%), respectively. Regarding mixed infection, 17 horses (3.4%) were seropositive for both S. neurona and T. gondii, 16 (3.2%) for T. gondii and Neospora spp. and 14 (2.8%) for S. neurona and Neospora spp. The associations between seropositivity and variables relating to the structure of the farm, management and health were analyzed using the logistic regression analysis, through the generalized estimating equations (GEE). The results suggest that the south of Minas Gerais is an enzootic area for S. neurona, T. gondii and Neospora spp. among horses, with prevalence of asymptomatic subclinical or chronic infections.

Seroepidemiology of Sarcocystis neurona, Toxoplasma gondii and Neospora spp. among horses in the south of the state of Minas Gerais, Brazil / Soroepidemiologia de Sarcocystis neurona, Toxoplasma gondii e Neospora spp. em Equinos no Sul do Estado de Minas Gerais, Brasil

Abstract The present study used the indirect fluorescent antibody test (IFAT) to determine the seroprevalence of Sarcocystis neurona, Toxoplasma gondii and Neospora spp., and evaluated the variables associated with these infections among 506 apparently healthy horses, reared in the south of the state of Minas Gerais, Brazil. This study was conducted between April 2012 and October 2013. Among the horses, the true prevalence of S. neurona was 26% (95% CI: 22.0-30.4%), T. gondii 19.9% (95% CI: 15.5-24.8%) and Neospora spp. 23.9% (95% CI: 19.9-28.1%); and among the farms, 88.3% (95% CI: 74.4-91.6%), 71.6% (95% CI: 41-92.8%) and 85% (95% CI: 70.7-96.1%), respectively. Regarding mixed infection, 17 horses (3.4%) were seropositive for both S. neurona and T. gondii, 16 (3.2%) for T. gondii and Neospora spp. and 14 (2.8%) for S. neurona and Neospora spp. The associations between seropositivity and variables relating to the structure of the farm, management and health were analyzed using the logistic regression analysis, through the generalized estimating equations (GEE). The results suggest that the south of Minas Gerais is an enzootic area for S. neurona, T. gondii and Neospora spp. among horses, with prevalence of asymptomatic subclinical or chronic infections.

Resumo Este estudo determinou, pela reação de imunofluorescência indireta (RIFI), a soroprevalência de Sarcocystis neurona, Toxoplasma gondii e Neospora spp., e avaliou as variáveis associadas com a infecção, em 506 equinos, aparentemente sadios, criados no Sul de Minas, Brasil. O estudo foi realizado no período de abril de 2012 a outubro de 2013. Entre equinos, a prevalência verdadeira para S. neurona foi de 26% (IC 95%= 22,0-30,4%); para T. gondii de 19,9% (IC 95%= 15,5-24,8%); e para Neospora spp. de 23,9% (IC 95%= 19,9-28,1%); e entre propriedades, 88,3% (IC 95%= 74,4-91,6%), 71,6% (IC 95% = 41-92,8%), e 85% (IC 95%= 70,7-96,1%), respectivamente. Em relação à infecção mista, 17 (3,4%) equinos foram soropositivos para S. neurona e T. gondii, 16 (3,2%) para T. gondii e Neospora spp., e 14 (2,8%) para S. neurona e Neospora spp. A associação entre soropositividade e variáveis relacionadas à estrutura da propriedade, manejo e sanidade, foi analisada, utilizando-se a análise de regressão logística estimada por Generalized Estimating Equations (GEE). Os resultados sugerem que o Sul de Minas é área enzoótica para S. neurona, T. gondii e Neospora spp. em equinos, com predomínio de infecções subclínicas ou crônicas, assintomáticas.

Prevalence and risk factors of Theileria equi infection in horses in Minas Gerais, Brazil.

Theileria equi, a protozoon in the phylum Apicomplexa, is the causative agent of equine theileriosis. The aim of this cross-sectional study was to determine the prevalence of IgG antibodies against T. equi, by using the indirect fluorescent antibody test (IFAT) reaction and correlating the serostatus with some epidemiological variables relating to the way in which Mangalarga Marchador horses are raised in southern Minas Gerais, Brazil. In this study, 506 horses were used, all clinically healthy, on 53 horse farms distributed across 27 municipalities in southern Minas Gerais. The statistical tests, comprising the chi-square test and generalized estimating equations (GEE), were performed in the SPSS Statistics 20.0 software. The true seroprevalence of T. equi among the horses was 57.0% (288 out of 506; ranging from 52.1 to 62.0%) and among horse farms, 98.1% (52 out of 53; ranging from 90.3 to 99.9%). The horse farms on which the majority of the horses presented good body condition and which did not use chemical products to kill ticks when new horses were introduced, had horses over the age of 5years, comprised <100ha in area and did not use embryo transfer showed greater seroprevalence of T. equi (p<0.05). The results from this study make it possible to state that infection with T. equi is endemic in the south of Minas Gerais and is widely distributed among horse farms raising Mangalarga Marchador horses. However, these infections are subclinical or chronic.

Factors associated with seroprevalence of Neospora caninum in dairy cattle in southeastern Brazil.

Neosporosis is an infectious disease caused by Neospora caninum, an obligate intracellular cyst-forming protozoan considered a major cause of miscarriage in dairy cattle in many parts of the world. This cross-sectional study evaluated the relationship between reproductive abnormalities and seropositivity to N. caninum in 1,204 dairy cows from 40 farms located in the state of Minas Gerais, southeastern Brazil. Producers were interviewed, and blood samples were collected to perform indirect immunofluorescence tests (IFAT 1:200). Association between reproductive abnormalities and seropositivity in cattle was evaluated with generalized estimating equations. The true herd-level seroprevalence of N. caninum was 95 % (83.3-99.1), while the individual-level true seroprevalence was 21.6 % (19.2-24.2). Several reproductive abnormalities were significantly associated with seropositivity to N. caninum: occurrence of repeated estrus (p=0.02; OR=3.84; 95 % CI=1.239-11.893), repeated miscarriages (p=0.001; OR=2.54; 95 % CI=1.423-5.402), and temporary anestrus (p=0.001; OR=3.44; 95 % CI=1.976-5.994). Furthermore, loose dogs (p=0.041; OR=2.20; 95 % CI=1.033-4.672) when fed raw meat (p=0.001; OR=1.91; 95 % CI=1.443-2.519) are risk factors for N. caninum infection. We observed that seropositivity to N. caninum in cattle increases risk of miscarriage by almost twice throughout the reproductive life of cows (p=0.004; OR=1.978; 95 % CI=1.249-3.131). Serologic evidence in this study indicates that N. caninum infection is widely distributed among dairy herds and significantly associated with reproductive disorders, especially miscarriage, repeated estrus, and temporary anestrus.

Seroprevalence for Neospora caninum in goats of Minas Gerais state, Brazil.

This study was aimed at determining the prevalence of anti-Neospora caninum antibodies in serum samples from 667 goats, collected from 90 herds in 90 municipalities in eight of the twelve mesoregions of Minas Gerais State. The presence of anti-N. caninum antibodies was determined by IFAT with a cut-off value of 1:50. The true herd-level seroprevalence in the entire study area was 75.2% (CI 95%: 59.5-90.9%). The true individual-level seroprevalence in the entire study area was 10.7% (CI 95%: 8.3-13.4%) with titers ranging from 50 (50.5%) to 3200 (1.7%). The serological evidence from this study indicated that N. caninum infection is widely distributed among goat-rearing herds in Minas Gerais and further studies are needed in order to evaluate the impact of this parasite as a cause of reproductive disorders.

Principal component analysis on the perceptions of milk producers about Rhipicephalus (Boophilus) microplus control in Minas Gerais.

Milk producers in Lavras, Passos and Divinópolis, Minas Gerais, were interviewed with the aim of evaluating their perceptions and attitudes regarding control over Rhipicephalus (Boophilus) microplus. Multivariate correlation between the variables was done by means of principal component analysis. The producers' perceptions and attitudes regarding R. (B.) microplus were similar: most of them did not have any basic knowledge of tick biology or control, and they applied acaricide products through backpack spraying, without any defined technical criteria. Some of the results obtained were: I. a negative correlation between schooling level and the frequency of spraying cattle with acaricides; II. a positive correlation between milk production, quality of equipment for acaricide application and technological level of the farm; III. farm properties with greater production and technification tended to keep the intervals between acaricide applications constant over the course of the year. After applying principal component analysis, a positive correlation was observed between schooling level, technological level of the farm and perceptions regarding R. (B.) microplus, but without any correlation with attitudes towards controlling this tick. It was concluded that higher technological level and schooling level improved the producers' perceptions relating to the biology of the tick R. (B.) microplus, but did not achieve effectiveness with regard to using controls more rationally.

Quantification of vertical transmission of Neospora caninum in dairy cows in Minas Gerais, Brazil.

The objective of this cross-sectional study was to estimate the rate of vertical transmission and to investigate horizontal transmission of Neospora caninum and occurrences of reproductive abnormalities in seropositive dairy cows on two farms in the state of Minas Gerais, Brazil. The frequency of cows seropositive for N.caninum according to the indirect fluorescent antibody test (IFAT) was 39.4% (93/236) for Farm A and 31.4% (32/102) for the Farm B (p > 0.05). The mean vertical transmission rates for N. caninum were 29% and 9% for the herds of Farms A and B, respectively. No negative effects (p > 0.05) from infection by N.caninum were observed regarding milk production and occurrences of reproductive abnormalities in herds A and B.

Principal component analysis on the perceptions of milk producers about Rhipicephalus (Boophilus) microplus control in Minas Gerais / Análise de componente Principal da percepção dos produtores de leite sobre o controle do Rhipicephalus (Boophilus) microplus em Minas Gerais

Milk producers in Lavras, Passos and Divinópolis, Minas Gerais, were interviewed with the aim of evaluating their perceptions and attitudes regarding control over Rhipicephalus (Boophilus) microplus. Multivariate correlation between the variables was done by means of principal component analysis. The producers' perceptions and attitudes regarding R. (B.) microplus were similar: most of them did not have any basic knowledge of tick biology or control, and they applied acaricide products through backpack spraying, without any defined technical criteria. Some of the results obtained were: I. a negative correlation between schooling level and the frequency of spraying cattle with acaricides; II. a positive correlation between milk production, quality of equipment for acaricide application and technological level of the farm; III. farm properties with greater production and technification tended to keep the intervals between acaricide applications constant over the course of the year. After applying principal component analysis, a positive correlation was observed between schooling level, technological level of the farm and perceptions regarding R. (B.) microplus, but without any correlation with attitudes towards controlling this tick. It was concluded that higher technological level and schooling level improved the producers' perceptions relating to the biology of the tick R. (B.) microplus, but did not achieve effectiveness with regard to using controls more rationally.

Produtores de leite de Lavras, Passos e Divinópolis, MG, foram entrevistados com objetivo de avaliar sua percepção e atitude no controle do Rhipicephalus (Boophilus) microplus. A análise da correlação multivariada entre as variáveis foi feita através de componentes principais (ACP). A percepção e atitude sobre o R. (B.) microplus foram semelhantes entre os produtores, sendo que a maioria deles não tem o conhecimento básico sobre a biologia e o controle desse carrapato, aplicando os produtos carrapaticidas por meio de bomba costal, e sem critérios técnicos definidos. Alguns resultados obtidos foram: I. correlação negativa entre escolaridade e frequência de aplicação de carrapaticidas bovinos; II. correlação positiva entre produção de leite, qualidade do equipamento para aplicação carrapaticida e nível tecnológico da fazenda; III. propriedades com maior produção e tecnificação tenderam a manter o intervalo de aplicação carrapaticida constante ao longo do ano. Após aplicação da ACP foi observada correlação positiva entre escolaridade, nível tecnológico da fazenda e percepção sobre o R. (B.) microplus, porém, sem correlação com a atitude no controle deste carrapato. Concluiu-se que o nível tecnológico e a escolaridade melhoram a percepção dos produtores sobre a biologia do carrapato R. (B.) microplus, mas não alcança efetivos na utilização do controle de forma mais racional.

Occurrence of anti-Neospora caninum antibodies in dogs in rural areas in Minas Gerais, Brazil.

The aim of this study was to determine the frequency of anti-Neospora caninum antibodies and risk factors associated with seropositivity in 240 dogs from rural areas of the Lavras, Belo Horizonte and Nanuque regions, state of Minas Gerais, Brazil. The indirect fluorescence antibody test (IFAT) with a cutoff of 50 was used to assess the frequency of seropositive dogs. The risk factor analysis was performed using the Chi-square test (χ2) and multiple logistic regression. The frequency of seropositivity for N. caninum was 15% of the dogs (36/240). Presence of dogs without defined breed (p = 0.018; OR = 5.9) and presence of cattle on the farm (p = 0.053, OR = 4.3) were associated with N. caninum seropositivity. Dogs in the Nanuque region had higher seropositivity for N. caninum (29.9%) than did those in the Lavras (6.2%) and Belo Horizonte (2.2%) regions (p < 0.05). The presence of seropositive dogs in rural areas of Minas Gerais demonstrates the potential risk of horizontal transmission of N. caninum to cattle, especially from dogs without defined breed, which were four times more likely to be seropositive than purebred dogs were.

Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil.

The aim of this cross-sectional observational study was to determine the frequency and factors associated with infection by Eimeria spp. and gastrointestinal nematodes in 356 calves on 20 dairy farms located in southern Minas Gerais, Brazil. Ten species of Eimeria spp. were identified, of which E. bovis (37.6%) and E. zuernii (17.9%) were the most frequent. From fecal cultures, four genera of gastrointestinal nematodes were recovered, of which Cooperia spp. (74.6%) and Haemonchus (19.4%) were the most frequent. Variables relating to higher levels of technology used on dairy farms showed a significant association (p < 0.05) with higher OPG and EPG counts, and are discussed in this study.

Seroprevalence and risk factors for Neospora caninum in sheep in the state Minas Gerais, southeastern Brazil.

The aim of this study was to determine the prevalence and risk factors associated with infection due to Neospora caninum in serum samples from 488 sheep originating from 63 farms in 63 municipalities distributed across eight of the twelve mesoregions of the state Minas Gerais, southeastern Brazil. For detection of N. caninum the sheep serum samples were subjected to the indirect fluorescence antibody test (IFAT ≥ 50). To identify the risk factors associated with infection due to N. caninum a questionnaire was filled out for each herd by interviewing, the individual responsible for the herd, demanding information on the general characteristics of the property. Sixty-four sheep sera (13.1%; 95% CI=10.3-16.4) presented IgG-specific anti-N. caninum antibodies with the following titers: 50 (49; 76.6%), 100 (7; 10.9%), 200 (4; 6.2%), 400 (3; 4.7%) and 800 (1; 1.6%). The prevalence of infected sheep per mesoregion ranged from 0 to 28.1%. Out of the 63 farms sampled, 31 (49.2%; 95% CI=36.4-62.1) presented at least one seropositive sheep. No significant association was found between the presence of anti-N. caninum antibodies and the risk factors evaluated on the farms, except for the mesoregion variable (p=0.004; OR=0.429; CI95%=0.182-1.008). These results indicate that there is a need for additional research to define the epidemiological importance of this parasite as a cause of reproductive problems in sheep herds in Minas Gerais.

Occurrence of anti-Neospora caninum antibodiesin dogs in rural areas in Minas Gerais, Brazil / Ocorrência de anticorpos anti-Neospora caninum em cães de áreas rurais em Minas Gerais, Brasil

The aim of this study was to determine the frequency of anti-Neospora caninum antibodies and risk factors associated with seropositivity in 240 dogs from rural areas of the Lavras, Belo Horizonte and Nanuque regions, state of Minas Gerais, Brazil. The indirect fluorescence antibody test (IFAT) with a cutoff of 50 was used to assess the frequency of seropositive dogs. The risk factor analysis was performed using the Chi-square test (χ2) and multiple logistic regression. The frequency of seropositivity for N. caninum was 15% of the dogs (36/240). Presence of dogs without defined breed (p = 0.018; OR = 5.9) and presence of cattle on the farm (p = 0.053, OR = 4.3) were associated with N. caninum seropositivity. Dogs in the Nanuque region had higher seropositivity for N. caninum (29.9%) than did those in the Lavras (6.2%) and Belo Horizonte (2.2%) regions (p < 0.05). The presence of seropositive dogs in rural areas of Minas Gerais demonstrates the potential risk of horizontal transmission of N. caninum to cattle, especially from dogs without defined breed, which were four times more likely to be seropositive than purebred dogs were.

O objetivo deste estudo foi determinar a frequência de anticorpos anti-Neospora caninum e fatores de risco associados à soropositividade, em 240 cães de áreas rurais, nas regiões de Lavras, Belo Horizonte e Nanuque, Minas Gerais, Brasil. Foi utilizada a reação de imunofluorescência indireta (RIFI), com um ponto de corte igual a 50, para avaliar a frequência de cães soropositivos. A análise dos fatores de risco foi realizada pelo teste de Qui-quadrado (χ2) e regressão logística múltipla. A frequência de cães soropositivos para N. caninum foi de 15% (36/240). A presença de cães sem raça definida (SRD) (p = 0,018; OR = 5,9) e bovinos na propriedade (p = 0,053; OR = 4,3) foi associada à soropositividade pelo N. caninum. A frequência de cães soropositivos foi mais elevada na região de Nanuque (29,9%), quando comparados aos das regiões de Lavras (6,2%) e Belo Horizonte (2,2%) (p < 0,05). A presença de cães soropositivos, em áreas rurais de Minas Gerais, demonstra o risco potencial da transmissão horizontal de N. caninum para os bovinos, especialmente os cães SRD, que apresentaram quatro vezes mais a chance de serem soropositivos em relação aos cães com raça definida.

Occurrences of Eimeria spp. and gastrointestinal nematodes in dairy calves in southern Minas Gerais, Brazil / Ocorrência de Eimeria spp. e nematódeos gastrintestinais em bezerros no sul de Minas Gerais, Brasil

The aim of this cross-sectional observational study was to determine the frequency and factors associated with infection by Eimeria spp. and gastrointestinal nematodes in 356 calves on 20 dairy farms located in southern Minas Gerais, Brazil. Ten species of Eimeria spp. were identified, of which E. bovis (37.6%) and E. zuernii (17.9%) were the most frequent. From fecal cultures, four genera of gastrointestinal nematodes were recovered, of which Cooperia spp. (74.6%) and Haemonchus (19.4%) were the most frequent. Variables relating to higher levels of technology used on dairy farms showed a significant association (p < 0.05) with higher OPG and EPG counts, and are discussed in this study.

O objetivo deste estudo foi determinar a frequência e os fatores associados à infecção por Eimeria spp. e nematódeos gastrintestinais, em 356 bezerras provenientes de 20 rebanhos leiteiros, localizados no sul de Minas Gerais, Brasil. Foram identificadas dez espécies de Eimeria spp., sendo E. bovis (37,6%) e E. zuernii (17,9%) as mais frequentes. Nas coproculturas, foram recuperados quatro gêneros de nematódeos gastrintestinais, sendo os mais frequentes Cooperia spp. (74,6%) e Haemonchus spp. (19,4%).Variáveis relacionadas a um maior nível de tecnificação das propriedades leiteiras apresentaram associação significativa (p < 0,05), com maiores contagens de OoPG e OPG, e são discutidas neste estudo.

Quantification of vertical transmission of Neospora caninum in dairy cows in Minas Gerais, Brazil / Quantificação da transmissão vertical de Neospora caninum em vacas leiteiras de Minas Gerais, Brasil

The objective of this cross-sectional study was to estimate the rate of vertical transmission and to investigate horizontal transmission of Neospora caninum and occurrences of reproductive abnormalities in seropositive dairy cows on two farms in the state of Minas Gerais, Brazil. The frequency of cows seropositive for N.caninum according to the indirect fluorescent antibody test (IFAT) was 39.4% (93/236) for Farm A and 31.4% (32/102) for the Farm B (p > 0.05). The mean vertical transmission rates for N. caninum were 29% and 9% for the herds of Farms A and B, respectively. No negative effects (p > 0.05) from infection by N.caninum were observed regarding milk production and occurrences of reproductive abnormalities in herds A and B.

O objetivo deste estudo transversal foi estimar a taxa de transmissão vertical e investigar a transmissão horizontal de Neospora caninum, e a ocorrência de alterações reprodutivas em vacas leiteiras soropositivas em duas fazendas no Estado de Minas Gerais, Brasil. A frequência de vacas soropositivas a N. caninum pelo teste de imunofluorescência indireta (RIFI) foi de 39,4% (93/236) e 31,4% (32/102) para as fazendas A e B, respectivamente. A taxa média de transmissão vertical de N. caninum, respectivamente, foi de 29% e 9% para os rebanhos A e B. Não foi observado nenhum efeito negativo (p > 0,05) da infecção por N. caninum sobre a produção de leite e a ocorrência de alterações reprodutivas nos rebanhos A e B.

Perceptions about the biology of Rhipicephalus (Boophilus) microplus among milk producers in Divinópolis, Minas Gerais.

One hundred semi-systematized interviews were applied with the aim of surveying the perceptions of milk producers in the municipality of Divinópolis, Minas Gerais regarding the biology of the tick Rhipicephalus (Boophilus) microplus. Content analysis was conducted on each of the variables surveyed and their descriptions, highlighting the higher frequencies in order to construct profiles of perceptions about each of the matters surveyed. In addition, each of the producers was categorized regarding their readiness to proceed with efficient control, from the assessment of their responses. Among the variables surveyed were the tick lifespan, duration of parasitic life, time of greatest incidence, survival in pastures and egg-laying volume. These questions are considered important for defining the knowledge needed for rational combat. It was concluded that the information needed for adopting effective practices to combat ticks was insufficient among the milk farm properties in Divinópolis. Moreover, the producers interviewed had a good perception of what they observed in their daily routine, but did not have complementary information about the tick life cycle.

Frequency of species of Eimeria in females of the Holstein-Friesian breed at the post-weaning stage during autumn and winter.

The frequency of species of the genus Eimeria in a dairy herd in the municipality of Boa Esperança, Southern region of the State of Minas Gerais was assessed. From 37 females of the Friesian breed aged three to seven months, 259 feces samples were analyzed between May and September 2008. The examinations to quantify oocysts per gram of feces (OPG) and identify Eimeria species were conducted at the Veterinary Parasitology Laboratory of the Federal University of Lavras. Eleven species of Eimeria were identified, namely: E. bovis (23.2%), E. zuernii (22.6%), E. ellipsoidalis (20.3%), E. cylindrica (14.1%), E. subspherica (5.4%), E. canadensis (3.5%), E. alabamensis (2.4%), E. auburnensis (2.4%), E. pellita (2.1%), E. brasiliensis (2%) and E. bukidnonensis (1.9%). E. bovis, E. zuernii and E. ellipsoidalis were the most frequent and the ones with the highest oocyst shedding over time (p < 0.05). Differences in OPG counts were found between most months studied (p < 0.05). The large number of Eimeria species found, in particular E. bovis and E. zuernii, indicates that Eimeria sp. has significant pathogenic potential in dairy cattle in the South of Minas Gerais.