PESQUISA VETERINÁRIA BRASILEIRA

Abstract in English:

ABSTRACT.- Martins I.V.F., Verocai G.G., Correia T.R., Melo R.M.P.S., Pereira M.J.S., Scott F.B. & Grisi L. 2009. Survey on control and management practices of equine helminths infection. Pesquisa Veterinária Brasileira 29(3):253-257. Departamento de Medicina Veterinária, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Cx. Postal 16, Alegre, ES 29500-000, Brazil. E-mail: isabella@cca.ufes.br Twenty-nine stud farms were selected in the Medium Paraíba region of the Rio de Janeiro state, Brazil. After an interview with the person responsible for the animals, faecal samples were collected from mares and analyzed via the EPG technique, faecal cultures, Sedimentation-centrifugo-flotation, and modified Ueno and Baermann techniques. The prevalence of helminths in the mares and in the stud farms was calculated. The stocking rates of pasture, change of horse bedding, absence of pasture rotation, absence of technology in the property, and less frequent treatment of the animals were associated with a greater prevalence of helminths, showing that these variables must be considered in equine control programs. The intensity of the parasitism was also associated with the stocking rate of pasture, absence of dunghill, presence of the animals only in paddocks, lack of technology in the property, less frequent treatment of the animals, and absence of the use of rotation regarding the anthelmintic class.

• Control practices management helminths treatment horses

Abstract in Portuguese:

ABSTRACT.- Martins I.V.F., Verocai G.G., Correia T.R., Melo R.M.P.S., Pereira M.J.S., Scott F.B. & Grisi L. 2009. Survey on control and management practices of equine helminths infection. Pesquisa Veterinária Brasileira 29(3):253-257. Departamento de Medicina Veterinária, Centro de Ciências Agrárias, Universidade Federal do Espírito Santo, Cx. Postal 16, Alegre, ES 29500-000, Brazil. E-mail: isabella@cca.ufes.br Twenty-nine stud farms were selected in the Medium Paraíba region of the Rio de Janeiro state, Brazil. After an interview with the person responsible for the animals, faecal samples were collected from mares and analyzed via the EPG technique, faecal cultures, Sedimentation-centrifugo-flotation, and modified Ueno and Baermann techniques. The prevalence of helminths in the mares and in the stud farms was calculated. The stocking rates of pasture, change of horse bedding, absence of pasture rotation, absence of technology in the property, and less frequent treatment of the animals were associated with a greater prevalence of helminths, showing that these variables must be considered in equine control programs. The intensity of the parasitism was also associated with the stocking rate of pasture, absence of dunghill, presence of the animals only in paddocks, lack of technology in the property, less frequent treatment of the animals, and absence of the use of rotation regarding the anthelmintic class.

Abstract in English:

ABSTRACT.- Santos T.R.B., Farias N.A.R., Cunha Filho N.A., Pappen F.G. & Vaz Junior I.S. 2009. [Studies of the management of the tick Rhipicephalus (Boophilus) microplus in southern Rio Grande do Sul, Brazil.] Abordagem sobre o controle do carrapato Rhipicephalus (Boophilus) microplus no sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(1):65-70. Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: tsantos@ufpel.edu.br In the southern region of Rio Grande do Sul, cattle become infested with Rhipicephalus (B.) microplus mainly between October and April due to the climatic conditions. In addition to knowing its life cycle, knowledge of parasite’s epidemiology is essential to establish management strategies. Epidemiological studies on resistance to acaricides in Rio Grande do Sul as well as in the rest of Brazil are scarce. Moreover, the large geographical area and the structural deficiency with respect to the use and access to databases make reliable data difficult to obtain. The present study surveyed the perception by cattle breeders in the southern region of Rio Grande do Sul in regards of identification of R. (B.) microplus populations that are difficult to manage using acaricides, as well as the risk factors for the selection of resistant tick populations. Tick management data on beef cattle in 85 properties of seven municipalities were collected. The results revealed that the difficulty in tick management correlated positively with levels of education of the farm owners (up to elementary school, OR = 3.67 and p = 0.01) and with the yearly number of acaricide applications (over four, with OR = 4.05 and p= 0.006). These results also suggest that properties with more than 100 beef cattle under extensive farming conditions in the southern region of Rio Grande do Sul show characteristics that may contribute to longer acaricide lifetimes as compared to other regions in the Country.

• Rhipicephalus (Boophilus) microplus risk factors resistance acaricides South Brazil

Abstract in Portuguese:

ABSTRACT.- Santos T.R.B., Farias N.A.R., Cunha Filho N.A., Pappen F.G. & Vaz Junior I.S. 2009. [Studies of the management of the tick Rhipicephalus (Boophilus) microplus in southern Rio Grande do Sul, Brazil.] Abordagem sobre o controle do carrapato Rhipicephalus (Boophilus) microplus no sul do Rio Grande do Sul. Pesquisa Veterinária Brasileira 29(1):65-70. Faculdade de Veterinária, Universidade Federal de Pelotas, Campus Universitário s/n, Cx. Postal 354, Pelotas, RS 96010-900, Brazil. E-mail: tsantos@ufpel.edu.br In the southern region of Rio Grande do Sul, cattle become infested with Rhipicephalus (B.) microplus mainly between October and April due to the climatic conditions. In addition to knowing its life cycle, knowledge of parasite’s epidemiology is essential to establish management strategies. Epidemiological studies on resistance to acaricides in Rio Grande do Sul as well as in the rest of Brazil are scarce. Moreover, the large geographical area and the structural deficiency with respect to the use and access to databases make reliable data difficult to obtain. The present study surveyed the perception by cattle breeders in the southern region of Rio Grande do Sul in regards of identification of R. (B.) microplus populations that are difficult to manage using acaricides, as well as the risk factors for the selection of resistant tick populations. Tick management data on beef cattle in 85 properties of seven municipalities were collected. The results revealed that the difficulty in tick management correlated positively with levels of education of the farm owners (up to elementary school, OR = 3.67 and p = 0.01) and with the yearly number of acaricide applications (over four, with OR = 4.05 and p= 0.006). These results also suggest that properties with more than 100 beef cattle under extensive farming conditions in the southern region of Rio Grande do Sul show characteristics that may contribute to longer acaricide lifetimes as compared to other regions in the Country.

Abstract in English:

ABSTRACT.- Deleito C.S.R & Moya Borja G.E. 2008. [Neem (Azadirachta indica): An alternative for controlling flies associated with animal breeding.] Nim (Azadirachta indica): uma alternativa no controle de moscas na pecuária. Pesquisa Veterinária Brasileira 28(6):293-298. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: claudiasayao@terra.com.br Flies Lucilia cuprina, Chrysomya megacephala, Cochliomyia hominivorax and Musca domestica, are among the most important arthropod pests of livestock, which produce myiasis and carry pathogenic microorganisms. The purpose of this study was to test of efficacy of various concentrations of neem oil on pupae of the above mentioned flies under laboratory and in field conditions. Reduction of fly emergence from treated pupae with 0.6 per cent of neem oil was 95.6 per cent under laboratory conditions and 94.5 per cent when applied on the soil, where the cattle rest during the night. The application of neem oil at 0.6 per cent on the soil is a viable alternative for controlling pupae of L. cuprina, C. megacephala, C. hominivorax and M. domestica.

• Botanical insecticide Lucilia cuprina Chrysomya megacephala Cochliomyia hominivorax Musca domestica

Abstract in Portuguese:

ABSTRACT.- Deleito C.S.R & Moya Borja G.E. 2008. [Neem (Azadirachta indica): An alternative for controlling flies associated with animal breeding.] Nim (Azadirachta indica): uma alternativa no controle de moscas na pecuária. Pesquisa Veterinária Brasileira 28(6):293-298. Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000, Brazil. E-mail: claudiasayao@terra.com.br Flies Lucilia cuprina, Chrysomya megacephala, Cochliomyia hominivorax and Musca domestica, are among the most important arthropod pests of livestock, which produce myiasis and carry pathogenic microorganisms. The purpose of this study was to test of efficacy of various concentrations of neem oil on pupae of the above mentioned flies under laboratory and in field conditions. Reduction of fly emergence from treated pupae with 0.6 per cent of neem oil was 95.6 per cent under laboratory conditions and 94.5 per cent when applied on the soil, where the cattle rest during the night. The application of neem oil at 0.6 per cent on the soil is a viable alternative for controlling pupae of L. cuprina, C. megacephala, C. hominivorax and M. domestica.

Abstract in English:

ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.

• Visceral leishmaniasis Leishmania infantum Lutzomyia longipalpis control dogs epidemiology Brazil

Abstract in Portuguese:

ABSTRACT.- Julião F.S., Souza B.M.P.S., Freitas D.S.,Oliveira L.S., Larangeira D.F., Dias-Lima A.G.,Souza V.M.M., Barrouin-Melo S.M., Moreira Jr E.D., Paule B.J.A. & Franke C.R. 2007. [Investigation of risk areas as complemental methodology for the control of canine visceral leishmaniasis.] Investigação de áreas de risco como metodologia complementar ao controle da leishmaniose visceral canina. Pesquisa Veterinária Brasileira 27(8):319-324. Laboratório de Infectologia Veterinária, Escola de Medicina Veterinária, Universidade Federal da Bahia, Av. Adhemar de Barros 500, Ondina, Salvador, BA 40170-110, Brazil. E-mail: franke@ufba.br Risk areas of canine visceral leishmaniasis in the city of Camaçari, Bahia, Brazil, were investigated. A total of 278 dogs from 141 homes pertaining to 20 investigated risk areas was serologically screened (ELISA). The general seroprevalence was 21.7% (56/258) after exclusion of 20 dogs used at the beginning of the survey to limit the study area. The respective results of the univariated and multivariated analysis of factors related to infection of dogs by Leishmania chagasi, to vector distribu-tion pattern in the area and to the methodology used to localize the canine focuses are discussed.

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:

Groff F.H.S., Merlo M.A., Stoll P.A., Stepan A.L., Weiblen R. & Flores E.F. 2005. [Epidemiology and control of pseudorabies outbreaks in the state of Rio Grande do Sul, Brazil, 2003.] Epidemiologia e controle dos focos da doença de Aujeszky no Rio Grande do Sul, em 2003. Pesquisa Veterinária Brasileira 25(1):25-30. Depto Medicina Veterinária Preventiva, Universi-dade Federal de Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br Aujeszky’s disease (AD) or pseudorabies is an important viral disease of swine and has significant economic impact on the pig industry worldwide. The infection produces direct and indirect economic losses, mainly due to restrictions to international trade of swine products. Since the beginning of the 20th century, AD had been notified in several Brazilian regions, yet the state of Rio Grande do Sul (RS) remained as a “provisionally free” area under the International Organization of Epizooties (OIE) guidelines. In 2003, two outbreaks were notified in swine herds located in northern RS, boundary with Santa Catarina, a state where the infection is endemic. Control/eradication measures consisted in tracing back all swine movements, quarantine and eradication of the affected herds by sanitary slaughter under official inspection. In outbreak # 1 (Pinheirinho do Vale, January/2003) six herds were affected, one of which presented animals with clinical signs. Starting from this outbreak, 146 herds and 42.399 pigs were traced back, six herds (7.822 animals) being depopulated – the herd where the index outbreak plus five other herds with positive serology. The outbreak # 2 (Aratiba, September/2003) resulted in a wider spread of the infection, involving another three counties and 77 herds (9 with clinical signs, 68 with positive serology). From the index case, 109.316 pigs in 630 herds were traced back; 28.443 animals from positive herds were slaughtered. Total numbers reached 151.715 traced back animals in 776 herds; 71 herds were found serologically positive. The adopted measures were efficient to eliminate the outbreaks and to stop the disease spread to neighboring areas, reestablishing the sanitary status previous to the outbreaks.

• Aujeszky’s disease pseudorabies ADV PRV epidemiology.

Abstract in Portuguese:

Groff F.H.S., Merlo M.A., Stoll P.A., Stepan A.L., Weiblen R. & Flores E.F. 2005. [Epidemiology and control of pseudorabies outbreaks in the state of Rio Grande do Sul, Brazil, 2003.] Epidemiologia e controle dos focos da doença de Aujeszky no Rio Grande do Sul, em 2003. Pesquisa Veterinária Brasileira 25(1):25-30. Depto Medicina Veterinária Preventiva, Universi-dade Federal de Santa Maria (UFSM), Santa Maria, RS 97105-900, Brazil. E-mail: flores@ccr.ufsm.br Aujeszky’s disease (AD) or pseudorabies is an important viral disease of swine and has significant economic impact on the pig industry worldwide. The infection produces direct and indirect economic losses, mainly due to restrictions to international trade of swine products. Since the beginning of the 20th century, AD had been notified in several Brazilian regions, yet the state of Rio Grande do Sul (RS) remained as a “provisionally free” area under the International Organization of Epizooties (OIE) guidelines. In 2003, two outbreaks were notified in swine herds located in northern RS, boundary with Santa Catarina, a state where the infection is endemic. Control/eradication measures consisted in tracing back all swine movements, quarantine and eradication of the affected herds by sanitary slaughter under official inspection. In outbreak # 1 (Pinheirinho do Vale, January/2003) six herds were affected, one of which presented animals with clinical signs. Starting from this outbreak, 146 herds and 42.399 pigs were traced back, six herds (7.822 animals) being depopulated – the herd where the index outbreak plus five other herds with positive serology. The outbreak # 2 (Aratiba, September/2003) resulted in a wider spread of the infection, involving another three counties and 77 herds (9 with clinical signs, 68 with positive serology). From the index case, 109.316 pigs in 630 herds were traced back; 28.443 animals from positive herds were slaughtered. Total numbers reached 151.715 traced back animals in 776 herds; 71 herds were found serologically positive. The adopted measures were efficient to eliminate the outbreaks and to stop the disease spread to neighboring areas, reestablishing the sanitary status previous to the outbreaks.

Abstract in English:

Lima E.S.C., Pinto P.S.A., Santos J.L., Vanetti M.C.D., Bevilacqua P.D., Almeida L.P., Pinto M.S. & Dias F.S. 2004. [Isolation of Salmonella sp and Staphylococcus aureus at swine slaughtering as subsidy for HACCP, the Hazard Analysis and Critical Control Point system.] Isolamento de Salmonella sp e Staphylococcus aureus no processo do abate suíno como subsídio ao sistema de Análise de Perigos e Pontos Críticos de Controle - APPCC. Pesquisa Veterinária Brasileira 24(4):185-190. Depto Veterinária, Universidade Federal de Viçosa, 36571-000 Viçosa, Minas Gerais, Brazil. E-mail: pintopsa@ufv.br This study was done to evaluate the superficial contamination of swine carcasses by Salmonella sp and Staphylococcus aureus, the identification of microbiological hazards in different segments of the processing line, and critical control points (CCPs), through the quantification of risks. A total of 120 surface swabbing carcasses were collected in a slaughterhouse: after the scalding/dehairing (point A), before evisceration (B), after evisceration and splitting (C), and after 24 hours of refrigeration (D). Salmonella sp and S. aureus were isolated from 14 (11.7%) carcasses. No statistical difference between the points studied was observed. The number of S. aureus isolated was between 1.2 and 1.5 log UFC/cm2. It was concluded that the risks observed were the same for both microorganisms.

• Salmonella sp Staphylococcus aureus swine carcass slaughterhouse HACCP.

Abstract in Portuguese:

Lima E.S.C., Pinto P.S.A., Santos J.L., Vanetti M.C.D., Bevilacqua P.D., Almeida L.P., Pinto M.S. & Dias F.S. 2004. [Isolation of Salmonella sp and Staphylococcus aureus at swine slaughtering as subsidy for HACCP, the Hazard Analysis and Critical Control Point system.] Isolamento de Salmonella sp e Staphylococcus aureus no processo do abate suíno como subsídio ao sistema de Análise de Perigos e Pontos Críticos de Controle - APPCC. Pesquisa Veterinária Brasileira 24(4):185-190. Depto Veterinária, Universidade Federal de Viçosa, 36571-000 Viçosa, Minas Gerais, Brazil. E-mail: pintopsa@ufv.br This study was done to evaluate the superficial contamination of swine carcasses by Salmonella sp and Staphylococcus aureus, the identification of microbiological hazards in different segments of the processing line, and critical control points (CCPs), through the quantification of risks. A total of 120 surface swabbing carcasses were collected in a slaughterhouse: after the scalding/dehairing (point A), before evisceration (B), after evisceration and splitting (C), and after 24 hours of refrigeration (D). Salmonella sp and S. aureus were isolated from 14 (11.7%) carcasses. No statistical difference between the points studied was observed. The number of S. aureus isolated was between 1.2 and 1.5 log UFC/cm2. It was concluded that the risks observed were the same for both microorganisms.

Abstract in English:

ABSTRACT.- Mota, M.A., Campos, A.K. &Araújo, J.V. [Biological control of helminth parasites of animais: Current stage and future outlook. A review.] Controle biológico de helmintos parasitos de animais: estágio atual e perspectivas futuras. Pesquisa Veterinária Brasileira 23(3):93-100. Depto Parasitologia, Universidade Federal de Minas Gerais, Cx. Postal 486, Belo Horizonte, MG 31270-901, Brazil.E-mail:mmot@icb.ufmg.br Biological control is a non-chemical alternative method with its main goal to reduce the amount of parasite population using natural antagonists. The administration of nematophagous fungi to animais has been considered an alternative in gastrointestinal helminthiasis prophylaxis. The nematophagous fungi produce trap-shaped structures, which are responsible for capturing and destroying the free-living stages of nematodes. The genera Arthrobotrys, Duddingtonia and Monacrosporium has been shown efficacy in laboratory and field experiments against cattle, equine, ovine and swine parasites. Severa) fungi formulations have been evaluated, but there is so far no commercial product available. The association of research groups with industry could improve the successful implementation of this control method.

• Biological control gastrointestinal helminths prophylaxis Controle biológico helmintos gastrintestinais profilaxia.

Abstract in Portuguese:

RESUMO.- Mota, M.A., Campos, A.K. & Araújo, J.V. [Biological control of helminth parasites of animais: Current stage and future outlook. A review.] Controle biológico de helmintos parasitos de animais: estágio atual e perspectivas futuras. Pesquisa Veterinária Brasileira 23(3):93-100. Depto Parasitologia, Universidade Federal de Minas Gerais, Cx. Postal 486, Belo Horizonte, MG 31270-901, Brazil.E-mail:mmot@icb.ufmg.br O controle biológico é um método desenvolvido para diminuir uma população de parasitas pela utilização de antagonista natural. A administração de fungos nematófagos aos animais domésticos é considerada uma promissora alternativa na profilaxia das helmintíases gastrintestinais parasitárias. Os fungos nematófagos desenvolvem estruturas em forma de armadilhas, responsáveis pela captura e destruição dos estágios infectantes dos nematóides. Os fungos dos gêneros Arthrobotrys, Duddingtonia e Monacrosporium têm demonstrado eficácia em experimentos laboratoriais e no campo no controle de parasitos de bovinos, eqüinos, ovinos e suínos. Diversas formulações fúngicas têm sido avaliadas, no entanto, ainda não há nenhum produto comercial disponível. A associação dos grupos de pesquisa e o envolvimento das indústrias poderão colaborar para o sucesso na implementação desta forma de controle.

Abstract in English:

ABSTRACT.- Bianchin I. & Alves R.G.O. 2002. [The hornfly, Haematobia irritans: behavior and damage caused in Nellore cows and pre-weaning calves.] Mosca-dos-chifres, Haematobia irritans: comportamento e danos em vacas e bezerros Nelore antes da desmama. Pesquisa Veterinária Brasileira 22(3):109-113. Embrapa Gado de Corte, Rodovia BR 262 Km 4, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. The hornfly and tosses caused by it in Nellore cows and pre-weaning calves where studied, using two groups of 60 animals each, one group with a natural infestation and the other without hornfly, during four consecutive years. It was seen that the number of flies on the cows did not exceed an average of 80 flies/animal in all years of observation. The majority of the cows (83%) had few flies, whereas 17% had larger numbers. The calves were infested with few flies. Rainfall in excess of 100 mm during short periods diminished fly infestation. Weight gain in the cows without flies (treated with insecticides) as well as their calves was greater than in the control cows, but not statistically significant (P>0.05). Mean percentage pregnancy during the four years was 15% more in treated cows than the non-treated animals, and this difference was probably due to the infestation of the bulls.

• Hornfly Haematobia irritans cattle epidemiology contral weight gains Mosca-dos-chifres bovinos epidemiologia controle ganho de peso.

Abstract in Portuguese:

RESUMO.- Bianchin I. & Alves R.G.O. 2002. [The hornfly, Haematobia irritans: behavior and damage caused in Nellore cows and pre-weaning calves.] Mosca-dos-chifres, Haematobia irritans: comportamento e danos em vacas e bezerros Nelore antes da desmama. Pesquisa Veterinária Brasileira 22(3):109-113. Embrapa Gado de Corte, Rodovia BR 262 Km 4, Cx. Postal 154, Campo Grande, MS 79002-970, Brazil. Estudaram-se o comportamentos e os danos causados pela mosca-dos-chifres em vacas e bezerros Nelore antes da desmama. Foram utilizados dois grupos de 60 animais cada um, sendo um grupo com infestação natural de moscas e o outro sem moscas, por quatro anos consecutivos. Observou-se que o número de moscas das vacas não ultrapassou a média de 80 moscas/animal, em todos os anos experimentais. A maioria das vacas (83%) apresentou poucas moscas, enquanto a minoria (17%) teve maior quantidade. Os bezerros foram pouco infestados pelas moscas. Chuvas acima de 100 mm em curto espaço de tempo diminuíram a infestação de moscas. O ganho de peso das vacas tratadas com inseticida (sem infestação por moscas) bem como os seus bezerros foi maior do que as vacas controle, porém não foi estatisticamente significativo (P>0,05). A percentagem média de prenhez, nos quatro anos, das vacas tratadas foi 15% superior a das não tratadas e esta diferença foi causada provavelmente pela infestação de moscas nos touros.

Abstract in English:

NO ABSTRACT

• INDEX TERMS: No Index Terms sem termos de indexação.

Abstract in Portuguese:

SEM RESUMO