True prevalence and spatial distribution of equine infectious anemia virus (EIAV) in horses from northeast region of Brazil

Equine infectious anemia (EIA) is a viral infection, caused by a lentivirus of the Retroviridae family, Orthoretrovirinael subfamily and its occurrence generates significant economic losses due to culling of positive animals as a measure of infection control. The objective of this work was to determine the prevalence of horses positive for equine infectious anemia virus (EIAV) and to identify the occurrence of areas with higher densities of cases in the states of Paraíba (PB), Pernambuco (PE), Rio Grande do Norte (RN) and Ceará (CE), Northeast region of Brazil, during the rainy (May and June) and dry (October and November) periods of 2017 and 2018. Serum samples from 6,566 horses from the states of PB, PE, RN and CE, Brazil, provided by the Laboratório Veterinária Diagnóstico - Ltda., were used. Serological diagnosis of EIA was performed using indirect enzyme-linked immunosorbent assay (ELISA) as a screening test and agar gel immunodiffusion test (AGID) as a confirmatory test. The apparent prevalence was obtained by dividing the number of seroreactive animals by the total number of animals, while the true prevalence was estimated by adjusting the apparent prevalence, considering the sensitivity (100%) and specificity (98.6%) of the diagnostic protocol used. For the construction of Kernel estimates, the Quartic function was used. In the dry season, of the 1,564 animals sampled, 28 were serologically positive, of which 19 belonged to the state of Ceará, 7 to Paraíba and 2 to Rio Grande do Norte. In 2018, it was observed that, during the rainy season, 26 of the 1,635 horses were seroreactive, with 19 cases resulting from Ceará, 4 from Paraíba and 3 from Pernambuco. In the dry season, 32 of the 1,526 animals were seroreactive to EIAV, of which 26 were from Ceará, 3 from Paraíba, 1 from Rio Grande do Norte and 2 from Pernambuco. In the dry period of 2017, the CE had a real prevalence of 1.22% (95% CI = 0.05 - 2.99%). In 2018, during the rainy season, prevalences of 0.03% (95% CI = 0 - 1.18%) were identified in CE and 1.69% (95% CI = 0 - 8.38%) in PE. Regarding the 2018 dry period, a prevalence of 1.32% (95% CI = 0.26 - 2.84%) was found in the state of CE. In both dry and rainy periods of 2017, the presence of spatial clusters of animals positive for EIA was observed, mainly in the border areas among the states of CE, PE, PB and RN. In 2018, there was a variation in the distribution of areas with higher densities of cases between the rainy and dry periods. The state of CE had the highest prevalence of positive animals and the presence of areas with higher densities of EIA cases in both climatic periods, in the years 2017 and 2018. In some municipalities of the CE, important sporting events of agglomeration of animals take place, which can favor the transmission of EIAV by facilitating the contact of infected and susceptible animals. Population density may be a factor associated with the higher prevalence observed in this region, as it has the second largest herd among the states studied. Higher densities indirectly contribute to the occurrence of infectious diseases, as they favor the contact of infected and susceptible animals. The occurrence of higher densities of cases in the border areas of the states of PE, RN, CE, and PB may be related to the greater movement of animals in these regions, favoring the indirect contact of infected horses with susceptible ones. The observed results demonstrate the circulation of the EIAV in four states in the Northeast region of Brazil.(AU)

Plantas tóxicas para ruminantes e equídeos da microrregião do Cariri Cearense / Plant poisonings in ruminants and horses in Southern Ceará, Northeastern Brazil

Em um levantamento, feito no período de agosto de 2009 a novembro de 2010, sobre as plantas tóxicas para ruminantes e equídeos no Cariri Cearense (municípios de Juazeiro do Norte, Crato, Barbalha e Missão Velha), foram realizadas 21 entrevistas a produtores, médicos veterinários, engenheiros agrônomos e técnicos agropecuários. As intoxicações por Ipomoea asarifolia, mencionada por 38% e 19% dos entrevistados como tóxicas para bovinos e ovinos, respectivamente, e Enterolobium contotisiliquum, mencionada como tóxica para bovinos (47,6% dos entrevistados) e ovinos (4,7%) foram as mais frequentemente mencionadas. Ocorrem, também, na região, intoxicações por Mascagnia rigida (mencionada por 38% do entrevistados), Anadenanthera colubrina var. cebil (=A. macrocarpa) (14%), Ricinus communis (14%), Thiloa glaucocarpa (9%) e Sorghum halepense (4%) em bovinos, Brachiaria decumbens em ovinos e bovinos (38%), Mimosa tenuiflora em ovinos, caprinos e bovinos (38%), Manihot spp. em bovinos e caprinos (28%) e Leucaena leucocephala em ovinos e equinos (4%). Seis plantas não conhecidas anteriormente como tóxicas, mas mencionadas como causa de intoxicação pelos entrevistados, foram testadas experimentalmente em diferentes doses. Somente Casearia commersoniana resultou tóxica para caprinos na dose diária de 20g kg-1 de peso vivo por 2-4 dias. Os sinais clínicos, semelhantes aos descritos pelos produtores, foram de relutância em movimentar-se, meteorismo discreto, polaquiúria, vocalização, ingurgitamento da jugular e pulso jugular, andar cambaleante, quedas, espasticidade dos membros, movimentos de pedalagem, opistótono, taquicardia e taquipneia, seguidos de bradicardia e bradipnéia. A morte ocorreu 6 e 19 horas após o início dos sinais. Não foram encontradas lesões macroscópicas nem histológicas de significação. Conclui-se que as intoxicações por plantas são uma causa importante de perdas econômicas para a região, cuja população é de 53.473 bovinos, 4.799 caprinos, 9.149 ovinos e 7.060 equídeos.

A survey on toxic plants for ruminants and equidae was performed on the municipalities of Juazeiro do Norte, Crato, Barbalha, and Missão Velha on the Ceará state, Northeastern Brazil. Twenty one interviews were realized with farmers, veterinary practitioners, agronomists and agriculture technicians. Poisonings by Ipomoea asarifolia mentioned in 38% and 19% interviews as toxic for bovines and sheep, respectively, and Enterolobium contotisiliquum, mentioned as toxic for cattle (47.6% of the interviews) and sheep (4.7%), were more frequent. Also occur in the region poisonings by Mascagnia rigida (38% of the interviews), Anadenanthera colubrina var. cebil (=A. macrocarpa) (14%), Ricinus communis (14%), Thiloa glaucocarpa (9%), and Sorghum halepense (4%) in cattle, Mimosa tenuiflora in cattle, sheep, and goats (38%), Brachiaria decumbens in sheep and cattle (38%), Manihot spp. in cattle and goats (28% ), and Leucaena leucocephala in sheep and horses (4%). Several plants previously unknown as toxic, but mentioned by the respondents as poisonous, were given to experimental animals at different doses. Only Casearia commersoniana was toxic to goats at the daily doses of 20g kg-1 body weight during 2-4 days. Clinical signs, similar to those reported by the farmers, were stiffness, mild bloat, polaquiuria, vocalization, jugular engorgement and pulsation, swaying gait, falling, spasticity, paddling movements, opisthotonos, and tachyicardia and dyspnea followed by bradycardia and bradypnea. Deaths occurred 6 and 19 hours after first clinical signs. No significant gross or histologic lesions were observed. It is concluded that poisonings by plants are important cause of losses in the region, which has a population of 53,473 bovines, 4,799 goats, 9,149 sheep, and 7,060 equidae.