PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Esposto E.M., Silva W.C.P., Reis C.M.F., Reis E.M.F., Ribeiro R.V., Rodrigues D.P. & Lázaro N.S. 2007. [Bacterial enteropathogens from fishes of a nutrient recycle system and its ecosystem.] Enteropatógenos bacterianos em peixes criados em uma estação de reciclagem de nutrientes e no ecossistema relacionado. Pesquisa Veterinária Brasileira 27(4):144-148. Departamento de Bacteriologia, Instituto Oswaldo Cruz, FIOCruz, Av. Brasil 4365, Pav. Rocha Lima, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil. E- mail: nslazaro@ioc.fiocruz.br The presence of bacterial enteropathogens from fishes of a nutrient recycle system from a Experimental Station in Petropolis, RJ, was evaluated in 72 samples from april 2000 to july 2001 Simultaneously was collected the mud used as organic manure and poultry beds localized next to the tanks. The isolation procedures included preenrichment in Peptone Water followed by enrichment with alcaline Peptone Water (pH 8.4-8.6), and streaked onto GSP Agar for the isolation of Aeromonas spp. and Plesiomonas shigelloides. For enteropathogenic bacteria of the Enterobacteriaceae family, 1ml samples were transferred for enrichment in Rappaport- Vassiladis broth and Kauffmann Tetrathionate Broth followed by streak onto Hektoen Enteric Agar and Salmonella-Shigella Agar. Simultaneously at each visit samples of water from fish and macrophyte tanks were collected for monitoring faecal coliforms (MPN) using A1 medium. Among the 116 isolates, Aeromonas spp. were the most frequent (67.2%) with 9 species (A. veronii, biogroup sobria, A. hidrophila, A. sobria, A. trota, A. eucrenophila, A. veronii biog. veronii, A. media, A. cavia and A. jandaei), followed by Edwardsiella tarda (16.4%), Plesiomonas shigelloides (12.9%) and Salmonella spp. (3.4%). The NMP of fecal coliforms showed higher values in the fish tanks (>1800/100ml).

• Enteropathogens wastewater fish farming

Abstract in Portuguese:

ABSTRACT.- Esposto E.M., Silva W.C.P., Reis C.M.F., Reis E.M.F., Ribeiro R.V., Rodrigues D.P. & Lázaro N.S. 2007. [Bacterial enteropathogens from fishes of a nutrient recycle system and its ecosystem.] Enteropatógenos bacterianos em peixes criados em uma estação de reciclagem de nutrientes e no ecossistema relacionado. Pesquisa Veterinária Brasileira 27(4):144-148. Departamento de Bacteriologia, Instituto Oswaldo Cruz, FIOCruz, Av. Brasil 4365, Pav. Rocha Lima, Manguinhos, Rio de Janeiro, RJ 21040-360, Brazil. E- mail: nslazaro@ioc.fiocruz.br The presence of bacterial enteropathogens from fishes of a nutrient recycle system from a Experimental Station in Petropolis, RJ, was evaluated in 72 samples from april 2000 to july 2001 Simultaneously was collected the mud used as organic manure and poultry beds localized next to the tanks. The isolation procedures included preenrichment in Peptone Water followed by enrichment with alcaline Peptone Water (pH 8.4-8.6), and streaked onto GSP Agar for the isolation of Aeromonas spp. and Plesiomonas shigelloides. For enteropathogenic bacteria of the Enterobacteriaceae family, 1ml samples were transferred for enrichment in Rappaport- Vassiladis broth and Kauffmann Tetrathionate Broth followed by streak onto Hektoen Enteric Agar and Salmonella-Shigella Agar. Simultaneously at each visit samples of water from fish and macrophyte tanks were collected for monitoring faecal coliforms (MPN) using A1 medium. Among the 116 isolates, Aeromonas spp. were the most frequent (67.2%) with 9 species (A. veronii, biogroup sobria, A. hidrophila, A. sobria, A. trota, A. eucrenophila, A. veronii biog. veronii, A. media, A. cavia and A. jandaei), followed by Edwardsiella tarda (16.4%), Plesiomonas shigelloides (12.9%) and Salmonella spp. (3.4%). The NMP of fecal coliforms showed higher values in the fish tanks (>1800/100ml).

Abstract in English:

ABSTRACT.- Rodrigues A.B., Athayde A.C.R., Rodrigues O.G., Silva W.W. & Faria E.B. 2007. [Evaluation of the efficacy of antihelmintics to control gastrointestinal nematodes in goats raised in the state of Paraíba.] Sensibilidade dos nematóides gastrintestinais de caprinos a anti-helmínticos na mesorregião do sertão paraibano. Pesquisa Veterinária Brasileira 27(4):162-166. Curso de Pós-Graduação de Medicina Veterinária em Pequenos Ruminantes, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-970 Patos, PB, Brazil. E-mail: adrianabonfimr@yahoo.com.br The objective was to evaluate conventional and alternative anthelminthic action on the sensibility of gastrointestinal nematodes in goats. Hundred and twenty goats of both sexes were distributed into 10 groups of 24 animals each (12 males and 12 females) and submitted to treatments of specific anthelminthic composition. The commercial drugs used were moxidectin 0.2%, albendazole, levamisol chlorhydrate, ivermectin and an aqueous extract of the purgative potato (Operculina hamiltonii). The reduction test was applied through egg counts per gram of feces and larval culture to evaluate resistance. The fecal samples were collected in the day when medication was accomplished (day base), at 7, 14 and 21 days after treatment. The following results for the reduction of Trichostrongyloidea eggs were obtained: Treatment of the females with Moxidectina reduced the egg counts to 92.8, 88.7 and 89.8%, of the males to 92.6, 96.2 and 98.1%; with Levamisol of the females to 96, 97.1 and 91%, of the males to 85.7, 94,2 and 100%; with Albendazol of the females 65, 60.3 and 75.4%, of the males 88.8, 88.8 and 55.5%; with Ivermectin of the females to 92.2, 68.6 and 70.6%, of the males to 41.7, 73.6 and 59.7%; and with the purgative potato of the females to 31.8, 34.1 and 49.4%, of the males to 61.5, 80.7 and 50%. In larval culture Haemonchus, followed by Bunostomum, Trichostrongylus, and Oesophagostomum, were identified even after treatments.

• Trichostrongyloidea gastrointestinal helminths anti-helminthics egg count

Abstract in Portuguese:

ABSTRACT.- Rodrigues A.B., Athayde A.C.R., Rodrigues O.G., Silva W.W. & Faria E.B. 2007. [Evaluation of the efficacy of antihelmintics to control gastrointestinal nematodes in goats raised in the state of Paraíba.] Sensibilidade dos nematóides gastrintestinais de caprinos a anti-helmínticos na mesorregião do sertão paraibano. Pesquisa Veterinária Brasileira 27(4):162-166. Curso de Pós-Graduação de Medicina Veterinária em Pequenos Ruminantes, Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-970 Patos, PB, Brazil. E-mail: adrianabonfimr@yahoo.com.br The objective was to evaluate conventional and alternative anthelminthic action on the sensibility of gastrointestinal nematodes in goats. Hundred and twenty goats of both sexes were distributed into 10 groups of 24 animals each (12 males and 12 females) and submitted to treatments of specific anthelminthic composition. The commercial drugs used were moxidectin 0.2%, albendazole, levamisol chlorhydrate, ivermectin and an aqueous extract of the purgative potato (Operculina hamiltonii). The reduction test was applied through egg counts per gram of feces and larval culture to evaluate resistance. The fecal samples were collected in the day when medication was accomplished (day base), at 7, 14 and 21 days after treatment. The following results for the reduction of Trichostrongyloidea eggs were obtained: Treatment of the females with Moxidectina reduced the egg counts to 92.8, 88.7 and 89.8%, of the males to 92.6, 96.2 and 98.1%; with Levamisol of the females to 96, 97.1 and 91%, of the males to 85.7, 94,2 and 100%; with Albendazol of the females 65, 60.3 and 75.4%, of the males 88.8, 88.8 and 55.5%; with Ivermectin of the females to 92.2, 68.6 and 70.6%, of the males to 41.7, 73.6 and 59.7%; and with the purgative potato of the females to 31.8, 34.1 and 49.4%, of the males to 61.5, 80.7 and 50%. In larval culture Haemonchus, followed by Bunostomum, Trichostrongylus, and Oesophagostomum, were identified even after treatments.

Abstract in English:

ABSTRACT.- Parizzi R.C., Miglino M.A., Maia M.O., Souza J.A., Santos J.M., Oliveira M.F. & Santos T.C. 2007. [Morphology of the ovary in rhea (Rhea americana).] Morfologia do ovário da ema (Rhea americana). Pesquisa Veterinária Brasileira 27(3):89-94. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, USP, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270. E-mail: tcsantos@usp.br The ovarian morphology of the sexually mature rhea (Rhea Americana) is described. Ovaries from 24 adult rheas in their reproductive age were collected in the slaughterhouse. Follicular diameters (n = 18) were measured and samples (n = 6) were fixed in 10% formaldehyde with 0.1M phosphate buffer at pH 7.4 for light microscopy. Results showed that the left ovary occupied the dorsal portion of the celomatic cavity in contact with the cranial portion of the left kidney and the suprarenal gland, being supported in the cavity through the mesovary. On the free surface of the ovary 72.4±17.09 follicles in different phases of development and 30.4±3.65 atretic follicles were observed. The follicles were linked to the ovarian surface by the follicular stalk and had a wide band surrounding its surface, the Stigma folliculare. Histologically, the ovary is constituted by a medulla, composed by connective tissue and vessels, and by a cortex with oocytes and follicles. The follicular wall is composed by the Theca externa and Theca interna, Stratum granulosum and the Zona radiata. The ovary surface is covered by a cubic epithelium, the germinal epithelium, on the connective tissue of the Tunica albuginea. The morphologic characteristics of the ovary of the rhea are due to the egg size in this species and generally similar to other birds.

• Ovary follicle morphology avian anatomy rhea Rhea americana

Abstract in Portuguese:

ABSTRACT.- Parizzi R.C., Miglino M.A., Maia M.O., Souza J.A., Santos J.M., Oliveira M.F. & Santos T.C. 2007. [Morphology of the ovary in rhea (Rhea americana).] Morfologia do ovário da ema (Rhea americana). Pesquisa Veterinária Brasileira 27(3):89-94. Departamento de Cirurgia, Faculdade de Medicina Veterinária e Zootecnia, USP, Av. Prof. Dr. Orlando Marques de Paiva 87, São Paulo, SP 05508-270. E-mail: tcsantos@usp.br The ovarian morphology of the sexually mature rhea (Rhea Americana) is described. Ovaries from 24 adult rheas in their reproductive age were collected in the slaughterhouse. Follicular diameters (n = 18) were measured and samples (n = 6) were fixed in 10% formaldehyde with 0.1M phosphate buffer at pH 7.4 for light microscopy. Results showed that the left ovary occupied the dorsal portion of the celomatic cavity in contact with the cranial portion of the left kidney and the suprarenal gland, being supported in the cavity through the mesovary. On the free surface of the ovary 72.4±17.09 follicles in different phases of development and 30.4±3.65 atretic follicles were observed. The follicles were linked to the ovarian surface by the follicular stalk and had a wide band surrounding its surface, the Stigma folliculare. Histologically, the ovary is constituted by a medulla, composed by connective tissue and vessels, and by a cortex with oocytes and follicles. The follicular wall is composed by the Theca externa and Theca interna, Stratum granulosum and the Zona radiata. The ovary surface is covered by a cubic epithelium, the germinal epithelium, on the connective tissue of the Tunica albuginea. The morphologic characteristics of the ovary of the rhea are due to the egg size in this species and generally similar to other birds.

Abstract in English:

ABSTRACT.- Brito L.G., Regitano L.C.A., Huacca M.E.F., Carrilho E. & Moya Borja G.E. 2007. Genotype characterization of the horn fly Haematobia irritans from different Brazilian geographic regions based on randomly amplified polymorphic DNA (RAPD) analysis. Pesquisa Veterinária Brasileira 27(1):1-5. Laboratório de Sanidade Animal, Embrapa Rondônia, BR 364 Km 5,5, Porto Velho, RO 78900-970, Brazil. E-mail: luciana@cpafro.embrapa.br Blood-sucking diptera are important parasites in bovine production systems, especially regarding confinement conditions. Haematobia irritans, the horn fly, is one of the most troublesome species within bovine production systems, due to the intense stress imposed to the animals. An important aspect while studying the variability within a species is the study of the geographic structure of its populations and, attempting to find out the genetic flow of Brazilian populations of horn fly, the RAPD technique, which is suited for this purpose, has been used. The use of molecular markers generated from RAPD made it possible to identify the geographic origin of samples from different Brazilian geographic regions, as well as to estimate the genotypic flow among the different Brazilian populations of the horn fly.

• Haematobia irritans genetic diversity RAPD-PCR molecular markers

Abstract in Portuguese:

ABSTRACT.- Brito L.G., Regitano L.C.A., Huacca M.E.F., Carrilho E. & Moya Borja G.E. 2007. Genotype characterization of the horn fly Haematobia irritans from different Brazilian geographic regions based on randomly amplified polymorphic DNA (RAPD) analysis. Pesquisa Veterinária Brasileira 27(1):1-5. Laboratório de Sanidade Animal, Embrapa Rondônia, BR 364 Km 5,5, Porto Velho, RO 78900-970, Brazil. E-mail: luciana@cpafro.embrapa.br Blood-sucking diptera are important parasites in bovine production systems, especially regarding confinement conditions. Haematobia irritans, the horn fly, is one of the most troublesome species within bovine production systems, due to the intense stress imposed to the animals. An important aspect while studying the variability within a species is the study of the geographic structure of its populations and, attempting to find out the genetic flow of Brazilian populations of horn fly, the RAPD technique, which is suited for this purpose, has been used. The use of molecular markers generated from RAPD made it possible to identify the geographic origin of samples from different Brazilian geographic regions, as well as to estimate the genotypic flow among the different Brazilian populations of the horn fly.

Abstract in English:

ABSTRACT.- Guedes K.M.R., Riet-Correa F., Dantas A.F.M., Simões S.V.D., Miranda Neto E.G., Nobre V.M.T. & Medeiros R.M.T. 2007. [Diseases of the central nervous system in goats and sheep of the semiarid.] Doenças do sistema nervoso central em caprinos e ovinos no semi-árido. Pesquisa Veterinária Brasileira 27(1):29-38. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br The knowledge of the diseases of domestic animals in the different Brazilian regions is important to determine measures for their control and prevention. The objective of this paper is to report the epidemiology, clinical signs and pathology of the diseases of the central nervous system (CNS) of goats and sheep in the Brazilian semiarid, mainly in the state of Paraíba, diagnosed at the Veterinary Hospital of the Federal University of Campina Grande, from January 2000 to May 2006. During the period, 365 cases or outbreaks were diagnosed in goats and 270 in sheep. From these, 63 (9.92%) were of diseases of the CNS, being 34 (9.31%) in goats and 29 (10.7%) in sheep. The main diseases were abscesses (19.04%), tetanus (15.9%), rabies (9.52%) poisoning by Ipomoea asarifolia (7.93%), listeriosis (6.34%), traumatism (6.34%), polioencephalo-malacia (4.77%), pregnancy toxemia (3.17%), enzootic ataxia (3.17%), and meningitis (3.17%). Other diseases diagnosed in only one opportunity (1.59%) were intoxications by Crotalaria retusa, Ipomoea carnea, Ipomoea sericophylla and Prosopis juliflora, otitis with encephalitis, malformation, lymphoblastic lymphosarcoma, medulloblastoma, and focal symmetric necrosis. In 6.34% of the cases diagnosis was unknown.

• Central nervous system diseases goats sheep semiarid

Abstract in Portuguese:

ABSTRACT.- Guedes K.M.R., Riet-Correa F., Dantas A.F.M., Simões S.V.D., Miranda Neto E.G., Nobre V.M.T. & Medeiros R.M.T. 2007. [Diseases of the central nervous system in goats and sheep of the semiarid.] Doenças do sistema nervoso central em caprinos e ovinos no semi-árido. Pesquisa Veterinária Brasileira 27(1):29-38. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, 58700-000 Patos, PB, Brazil. E-mail: franklin.riet@pesquisador.cnpq.br The knowledge of the diseases of domestic animals in the different Brazilian regions is important to determine measures for their control and prevention. The objective of this paper is to report the epidemiology, clinical signs and pathology of the diseases of the central nervous system (CNS) of goats and sheep in the Brazilian semiarid, mainly in the state of Paraíba, diagnosed at the Veterinary Hospital of the Federal University of Campina Grande, from January 2000 to May 2006. During the period, 365 cases or outbreaks were diagnosed in goats and 270 in sheep. From these, 63 (9.92%) were of diseases of the CNS, being 34 (9.31%) in goats and 29 (10.7%) in sheep. The main diseases were abscesses (19.04%), tetanus (15.9%), rabies (9.52%) poisoning by Ipomoea asarifolia (7.93%), listeriosis (6.34%), traumatism (6.34%), polioencephalo-malacia (4.77%), pregnancy toxemia (3.17%), enzootic ataxia (3.17%), and meningitis (3.17%). Other diseases diagnosed in only one opportunity (1.59%) were intoxications by Crotalaria retusa, Ipomoea carnea, Ipomoea sericophylla and Prosopis juliflora, otitis with encephalitis, malformation, lymphoblastic lymphosarcoma, medulloblastoma, and focal symmetric necrosis. In 6.34% of the cases diagnosis was unknown.

Abstract in English:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.

• BVDV-1 BVDV-2 Pestivirus phylogenetic analysis

Abstract in Portuguese:

ABSTRACT.- Cortez A., Heinemann M.B., Castro A.M.M.G., Soares M.S, Pinto A.M.V., Alfieri A.A., Flores E.F., Leite R.C. & Richtzenhain L.J. 2006. Genetic characterization of Brazilian bovine viral diarrhea virus isolates by partial nucleotide sequencing of the 5’-UTR region. Pesquisa Veterinária Brasileira 26(4):211-216. Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, Cidade Universitária, São Paulo, SP 05508-000, Brazil. E-mail: leonardo@usp.br Nineteen isolates of bovine viral diarrhea virus (BVDV) from Brazil were genetically characterized through partial nucleotide sequencing and analysis of the 5’UTR region. The isolates were grouped as BVDV-1 (11/19), BVDV-2 (6/19) or “atypical” pestivirus (2/19). Among the BVDV-1, eight isolates were classified as subgenotype BVDV-1a, whereas most (4 out of 6) BVDV-2 belonged to subgenotype 2b. Two isolates from aborted fetuses were not classified into any genetic group, being considered atypical BVDVs. Genetic diversity among Brazilian BVDV isolates may be responsible for vaccination and diag-nostic failure and therefore may influence the control strategies for BVDV infection in the country.

Abstract in English:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

• Status spongiosus astrocytic edema congenital diseases cattle

Abstract in Portuguese:

ABSTRACT.- Guedes K.M.R., Schild A.L. Riet-Correa F., Barros S.S. & Simões S.V.D. 2006. [Spongious degeneration in the central nervous system in Sindhi calves]. Degeneração esponjosa no sistema nervoso central de bezerros da raça Sindhi. Pesquisa Veterinária Brasileira 26(3):157-160. Centro de Saúde e Tecnologia Rural, Universidade Federal de Campina Grande, Campus de Patos, 58700-000 Patos, Paraíba, Brazil. E-mail franklin.riet@pesquisador.cnpq.br Spongy degeneration (status spongiosus) includes many histological alterations characterized by vacuoles in the neuropile in different regions of the central nervous system (CNS). The vacuolization can be caused by intramyelinic edema, as in maple syrup urine disease and some toxic diseases, or by astrocytic edema, as in citrullinemia. This paper reports a spongy degeneration in two Sindhi calves, a female and a male. Both calves were offspring from the same bull, and the herd had high degree of inbreeding. The female calf was born normal, but progressive nervous signs were observed since 2 months old. The male calf had progressive nervous signs since it was born. Both calves were euthanized with severe nervous signs when 4 months old. At necropsy the liver was pale in the male calf. Histological alterations were mild to accentuated vacuolization, mainly in the deep cerebral cortex, cerebellar white matter, grey matter of the spinal cord, internal capsule, and brain stem. Fatty degeneration was observed in the liver of both animals. On electron microscopy it was found that the status spongiosus was caused by astrocytic edema. It is suggested that the disease is caused by a metabolic hereditary error.

Abstract in English:

ABSTRACT.- Bianchin I., Koller W.W. & Detmann E. 2006. [The seasonality of Haematobia irritans in central Brazil.] Sazonalidade de Haematobia irritans no Brasil Central. Pesquisa Veterinária Brasileira 26(2):79-86. Área de Sanidade Animal, Embrapa Gado de Corte, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. E-mail: bianchin@cnpgc.embrapa.br Horn fly (Haematobia irritans) is one of the most important Brazilian cattle ectoparasites. Epidemiological studies are needed due the increasing difficulty of their chemical control. In order to obtain a better knowledge of their seasonal population dynamics, 14 days interval fly counts were made on 7-30 month old beef cattle, from winter 1996 to summer 2002. Horn fly population levels increase (P<0.05) was observed during the seasons of each infestation period (spring until autumn), mainly in spring and summer, and sometimes in autumn, followed by a significant reduction (P<0.05) in winter, when the relative humidity decreases to less than 60%. A straight (P<0.05) and immediate correlation between the relative humidity and the fly count was found, whilst the most evident effects of temperature and rain fall (P<0.05) were associated with counts done 42-56 days after attainment of the climatic data. The highest parasitism load (average number of flies per animal) observed for the genetic groups used were: Aberdeen Angus x Nellore = 173.5 (134-254); ½ Brown Swiss x Nellore = 183.5 (32-540); ¾ Aberdeen Angus x Nellore = 133.0 (18-374), and Valdostana x Nellore = 219.0 (58-620). Torrential rain falls during the initial half of the infestation period (spring until midsummer) are common in this region and were considered the main reason for the low to moderate population levels verified at that time, in comparison with those which occurred during the last half of the infestation period.

• Horn fly epidemiology population dynamics ectoparasites cattle.

Abstract in Portuguese:

ABSTRACT.- Bianchin I., Koller W.W. & Detmann E. 2006. [The seasonality of Haematobia irritans in central Brazil.] Sazonalidade de Haematobia irritans no Brasil Central. Pesquisa Veterinária Brasileira 26(2):79-86. Área de Sanidade Animal, Embrapa Gado de Corte, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. E-mail: bianchin@cnpgc.embrapa.br Horn fly (Haematobia irritans) is one of the most important Brazilian cattle ectoparasites. Epidemiological studies are needed due the increasing difficulty of their chemical control. In order to obtain a better knowledge of their seasonal population dynamics, 14 days interval fly counts were made on 7-30 month old beef cattle, from winter 1996 to summer 2002. Horn fly population levels increase (P<0.05) was observed during the seasons of each infestation period (spring until autumn), mainly in spring and summer, and sometimes in autumn, followed by a significant reduction (P<0.05) in winter, when the relative humidity decreases to less than 60%. A straight (P<0.05) and immediate correlation between the relative humidity and the fly count was found, whilst the most evident effects of temperature and rain fall (P<0.05) were associated with counts done 42-56 days after attainment of the climatic data. The highest parasitism load (average number of flies per animal) observed for the genetic groups used were: Aberdeen Angus x Nellore = 173.5 (134-254); ½ Brown Swiss x Nellore = 183.5 (32-540); ¾ Aberdeen Angus x Nellore = 133.0 (18-374), and Valdostana x Nellore = 219.0 (58-620). Torrential rain falls during the initial half of the infestation period (spring until midsummer) are common in this region and were considered the main reason for the low to moderate population levels verified at that time, in comparison with those which occurred during the last half of the infestation period.

Abstract in English:

Gomes M., Uieda W. & Latorre M.R.D.O. 2006. [Influence of sex differences in the same colony for chemical control of vampire Desmodus rotundus (Phyllostomidae) populations in the state of São Paulo, Brazil.] Influência do sexo de indivíduos da mesma colônia no controle químico das populações do morcego hematófago Desmodus rotundus (Phyllstomidae) no Estado de São Paulo. Pesquisa Veterinária Brasileira 26(1):38-43. Coordenadoria de Defesa Agropecuária/SP, Regional Mogi das Cruzes, Av. Cândido X.A.Sousa 35, Mogi das Cruzes, SP 08780-210, Brazil. E-mail: murilong@usp.br The aim of this study was to verify the fidelity to the diurnal roosts by the genders of the vampire bat Desmodus rotundus, and to analyse the Warfarin gel 2% effectiveness for reduction of the size of vampire bat colonies, when individuals of different sexes were treated. In 1999 and 2000, 626 vampire bats were mist netted while leaving at night 12 diurnal roosts in the state of São Paulo. They were marked, and 10% of the roost population received the Warfarin gel 2% treatment. In Test I only males were treated, in Test II only females were treated, and in Test III 5% of males and females were treated. After 5 and 10 days, the dead and the survivors were counted. Females were more loyal to the roosts (p<0,01) and better wide spreader of the Warfarin gel (p<0,01).

• Rabies vampire bats Desmodus rotundus Warfarin gel.

Abstract in Portuguese:

Gomes M., Uieda W. & Latorre M.R.D.O. 2006. [Influence of sex differences in the same colony for chemical control of vampire Desmodus rotundus (Phyllostomidae) populations in the state of São Paulo, Brazil.] Influência do sexo de indivíduos da mesma colônia no controle químico das populações do morcego hematófago Desmodus rotundus (Phyllstomidae) no Estado de São Paulo. Pesquisa Veterinária Brasileira 26(1):38-43. Coordenadoria de Defesa Agropecuária/SP, Regional Mogi das Cruzes, Av. Cândido X.A.Sousa 35, Mogi das Cruzes, SP 08780-210, Brazil. E-mail: murilong@usp.br The aim of this study was to verify the fidelity to the diurnal roosts by the genders of the vampire bat Desmodus rotundus, and to analyse the Warfarin gel 2% effectiveness for reduction of the size of vampire bat colonies, when individuals of different sexes were treated. In 1999 and 2000, 626 vampire bats were mist netted while leaving at night 12 diurnal roosts in the state of São Paulo. They were marked, and 10% of the roost population received the Warfarin gel 2% treatment. In Test I only males were treated, in Test II only females were treated, and in Test III 5% of males and females were treated. After 5 and 10 days, the dead and the survivors were counted. Females were more loyal to the roosts (p<0,01) and better wide spreader of the Warfarin gel (p<0,01).

Abstract in English:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.

• Trypanosomiasis Trypanosoma evansi infectious diseases encephalitis hematology pathology diseases of horses.

Abstract in Portuguese:

Rodrigues A., Fighera R.A., Souza T.M., Schild A.L., Soares M.P., Milano J. & Barros C.S.L. 2005. [Outbreaks of trypanosomiasis in horses by Trypanosoma evansi in the state of Rio Grande do Sul, Brazil: epidemiological, clinical, hematological, and pathological aspects.] Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos. Pesquisa Veterinária Brasileira 25(4):239-249. Depto Patologia, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil. E-mail: claudioslbarros@uol.com.br Cases of trypanosomiasis by Trypanosoma evansi were diagnosed in horses in the state of Rio Grande do Sul, Brazil, between 2003 and 2004. In one stud farm (Farm A) with 125 horses, 52 died. Additionally, around 80 mares were sent to Farm A to be bred. Of those, 66 became ill and 56 died after being returned to their farms of origin. Twenty one horses clinically affected by the disease were observed. Clinical signs included loss of weight (despite voracious appetite), lethargy, incoordination and instability of hindlimbs, atrophy of the large muscles of the hindlimbs, muscle weakness and paleness of mucosae. Specimens of T. evansi were detected in the blood drawn from four affected horses. Normocytic normochromic anemia with PCVs ranging from 15 to 31%, leucocytosis due to lymphocytosis associated to large atypical lymphocytes was observed in several affected horses. High levels of antibodies against T. evansi were detected in the serum of six horses from Farm A. Eight horses presented encephalic neurological signs such as circling, ataxia, blindness, excitation, falls, listlessness, proprioception deficits and head tilt. One horse assumed a “dog-seating position”. Necropsy findings included muscle atrophy, enlargement and lymphoid hyperplasia of the spleen and lymphnodes, edema and softening of the white and grey matter of the brain. Histologically, an overwhelming necrotizing panencephalitis was observed in the seven horses with encephalic signs. This panencephalitis was characterized by marked edema, demyelination and necrosis and perivascular infiltrates of 6-10 layers of lymphocytes and plasm cells affecting both the white and gray matter. Several plasm cells in the inflammatory infiltrate contained numerous eosinophilic globules in their cytoplasm (Mott cells). Similar histological lesions were observed in the spinal cord of the horse with the “dog-seating position”. The brains of five horses with the encephalic signs were submitted to immunohistochemistry stain by the streptavidin-biotin technique. In all of those five brains moderate to abundant specimens of T. evansi in the perivascular spaces and neuropile were marked by the specific antibody. Epidemiological, clinical, hematological, and pathological aspects of equine trypanosomiasis caused by T. evansi are discussed.