PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

• Rabies cattle sheep goats horses pathology clinical signs economical impact.

Abstract in Portuguese:

Lima E.F., Riet-Correa F., Castro R.S., Gomes A.A.B. & Lima F.S. 2005. [Clinical signs, distribution of the lesions in the central nervous system and epidemiology of rabies in northeastern Brazil.] Sinais clínicos, distribuição das lesões no sistema nervoso e epidemiologia da raiva em herbívoros na região Nordeste do Brasil. Pesquisa Veterinária Brasileira 25(4):250-264. Centro de Saúde e Tecnologia Rural, Campus de Patos, Universidade Federal de Campina Grande, Patos, PB 58700-000, Brazil. E-mail: riet@cstr.ufcg.br Twenty four outbreaks of rabies in cattle, 4 in horses, 2 in sheep, and 2 in goats are reported in northeastern Brazil. All outbreaks occurred in the state of Paraíba, except one in horses that occurred in the state of Rio Grande do Norte. All outbreaks, except one in sheep, were probably transmitted by vampire-bats, but the transmission by foxes (Dusicyon vetulus) is also possible. Clinical signs were characteristic for distribution of the lesions in the central nervous system (CNS). In cattle, signs were mainly of the paralytic form of rabies, caused by lesions on the spinal cord, brain stem and cerebellum; but some animals showed also depression, excitation and other signs due to cerebral lesions. In 3 out of 5 horses, the main clinical signs were due to lesions in the cerebrum, and 2 had the paralytic form. From 4 sheep and 2 goats affected, 4 showed clinical signs of the paralytic form; but in 1 goat and 1 sheep the main clinical signs were caused by cerebral lesions. All affected animals, except 1 goat, had a clinical manifestation period of 2-8 days. The only gross lesions were distention of the urinary bladder in 4 cattle and distention of the rectum in 2 others. Two horses had skin lesions due to traumatic injury. Histologic lesions were diffuse non-suppurative encephalomyelitis and meningitis. In the horses, and in one goat with a clinical manifestation period of 35 days, the lesions were more severe, with neuronal necrosis, neuronophagia, and presence of axonal spheroids. Negri bodies were found in 87% (20/23) of the cattle cases examined histologically. In small ruminants Negri bodies were found in 83% (5/6) of the cases. In sheep, goats and cattle, Negri bodies were more frequent in the cerebellum, but they were found also in brain stem, spinal cord and cerebrum. In horses, Negri bodies were found in small amounts only in the cortex of one animal, and in the cortex and hippocampus of another. Histologic lesions and Negri bodies in the trigeminal ganglia were less frequent than in the CNS. These results show that in rabies of herbivores, clinical signs and distribution of lesions in the CNS are variable, so that for the diagnosis and adequate clinical evaluation and the histologic study of different areas of the CNS are necessary. This also suggests that when the fluorescent antibody test and mouse inoculation test are negative, they should be repeated with samples from different areas of the brain and spinal cord. Frequency data of diseases from 4 diagnostic laboratories were used to estimate cattle deaths due to rabies in 3 Brazilian states. In Paraíba, with a population of 918,262 cattle, the annual death rate is estimated in 8,609 heads. In Mato Grosso do Sul, with a population of 23 millions cattle, deaths caused by rabies are estimated in 149,500 heads, and in Rio Grande do Sul, with a cattle population of 13 millions, cattle deaths due to rabies are estimated in 13,000 to 16,250 heads. If these data are used to estimate cattle losses in Brazil, with a cattle population of 195 millions, it can be estimated that 842,688 deaths are caused annually by rabies.

Abstract in English:

ABSTRACT.- Gomes P.R., Koller W.W., Gomes A., Carvalho C.J.B. & Zorzatto J.R. 2002. [Fanniid diptera vectors of Dermatobia hominis eggs in Campo Grande, MS, Brazil.] Dípteros fanídeos de ovos de Dermatobia hominis em Campo Grande, Mato Grosso do Sul. Pesquisa Veterinária Brasileira 22 (3):114-118. Laboratório de Ectoparasitologia, Embrapa Gado de Corte, BR 262 Km 4, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. This study was undertaken to determine the epidemiological importance of fanniid flies on warble fly infestations. The local species of Fanniidae as well as those utilized by Dermatobia hominis to carry its eggs were identitied, and the population dynamics of the most abundant species were studied. In order to accomplish this task, five traps with rotten bovine liver as bait were used. These traps were settled into a ciliate forest bordered by pastures and grazed continuously by cattle. The experiment was carried out at Embrapa Gado de Corte, in Campo Grande, Mato Grosso do Sul, Brazil, situated at 20º27‘S and 54°37’W. The capture of the insects was done weekly, from August 9, 1999 to August 3, 2000. A total of 40,629 fanniid flies which belonged to five different species of the genera Fannia were captured: E pusio, F. heydenii, E bahiensis and E longipila, and one species which needs further identification. The most frequent species was E pusio, with 63.20% of the total captured flies, followed by E heydenii with 28.82%. Eggs of D. hominis were observed only on 0.44% (45 specimens) of the E heydenii females captured, mainly on the ones captured in August and September. The average number for D. hominis eggs, per specimen, was 15.98±7.13. The only vector body region, where the eggs of D. hominis were found, was the abdomen. E heydenii predominated during the dry season (May to September) and at the beginning of the rainy season (October and November). The number of specimens bearing eggs of D. hominis was greater at the end of the annual dry season, what explains the high incidence of this parasite in cattle during September and October.

• Vectors warble fly epidemiology Brazilian savannas Vetores mosca-do-berne epidemiologia Cerrado.

Abstract in Portuguese:

RESUMO.- Gomes P.R., Koller W.W., Gomes A., Carvalho C.J.B. & Zorzatto J.R. 2002. [Fanniid diptera vectors of Dermatobia hominis eggs in Campo Grande, MS, Brazil.] Dípteros fanídeos de ovos de Dermatobia hominis em Campo Grande, Mato Grosso do Sul. Pesquisa Veterinária Brasileira 22 (3):114-118. Laboratório de Ectoparasitologia, Embrapa Gado de Corte, BR 262 Km 4, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. Determinou-se a importância epidemiológica de dípteros Fanniidae na infestação de mosca-do-berne, por meio da identificação das espécies presentes, da determinação daquelas utilizadas por Dermatobia hominis na veiculação de seus ovos, bem como, pelo conhecimento da dinâmica populacional das espécies mais abundantes. Foram utilizadas cinco armadilhas iscadas com fígado bovino cru deteriorado e colocadas em uma mata ciliar margeada por uma área de pastagem com presença constante de bovinos. O estudo foi desenvolvido em uma área da Embrapa Gado de Corte, em Campo Grande, Estado de Mato Grosso do Sul, Brasil, localizada a 20°27‘S e 54°37’W. A captura dos insetos foi realizada semanalmente durante o período de 09/08/1999 a 03/08/2000. Foi capturado um total de 40.629 moscas da família Fanniidae, pertencendo a cinco espécies do gênero Fannia: E pusio, E heydenii, E bahiensis e F. longipila, e uma a ser identificada. A espécie mais freqüente foi E pusio, com 63,20% do total capturado, seguida de E heydenii, com 28,82%. Somente 0,44% do total de femeas de E heydenii (45 exemplares) capturadas, principalmente nos meses de agosto e setembro, portavam ovos de D. hominis e o número médio, por indivíduo, foi de 15,98±7,13. Observaram-se ovos de D. hominis apenas na região abdominal dos vetores. F. heydenii predominou no período seco (maio a setembro) e início do período chuvoso do ano (outubro e novembro). O número de exemplares portando ovos de D. hominis foi maior no final do período seco do ano, o que explica a alta incidência deste parasito em bovinos nos meses de setembro e outubro.