Resultado da pesquisa (3)
Termo utilizado na pesquisa population dynamics
#1 - Seasonality of horn flies (Haematobia irritans) in the Brazilian semi-arid
Abstract in English:
The horn fly (Haematobia irritans) is a major livestock pest in Brazil. Despite of the regional needs, no studies assessing its importance and subsidizing its control are available for the Brazilian northeast. The present study aimed to know the population dynamics and determine the infestation levels of H. irritans on cattle in the semiarid region of the Paraíba state, in order to support control programs. The study was conducted at the Nucleus of Research for the Semiarid Tropics, Federal University of Campina Grande, municipality of Patos, Paraíba. During 42 months, from April 2011 to September 2014, horn fly counts were performed every 14 days in a Sindi herd (26 cows and a bull). The main climatic parameters were recorded daily. Horn fly infestations occurred throughout the study, with individual infestations above 100 flies at all counts, monthly mean infestations of up to 183 flies/cow and maximum individual infestations of 500 flies on cows and 1,800 flies on the bull. Influenced by microclimatic influence of large reservoirs, the horn fly population showed a bimodal behavior, with population peaks in October/November and March. No significant correlation between climatic factors and fly counts was found. In order to avoid infestation peaks and to reduce subsequent economic losses, control measures are recommended.
Abstract in Portuguese:
A mosca-dos-chifres (Haematobia irritans) é uma dos principais pragas que afetam a pecuária no Brasil. A despeito das carências regionais, inexistem estudos que avaliem sua importância e subsidiem seu controle no nordeste brasileiro. O presente estudo objetivou conhecer a dinâmica populacional e determinar os níveis de infestação da H. irritans no semiárido paraibano, visando subsidiar programas de controle. O estudo foi conduzido no Núcleo de Pesquisa para o Trópico Semiárido, Universidade Federal de Campina Grande, município de Patos, Paraíba. Durante 42 meses, de abril 2011 a setembro 2014, contagens de moscas-dos-chifres foram realizadas a cada 14 dias em um rebanho Sindi (26 vacas e um touro). Paralelamente, foram registrados diariamente os principais parâmetros climáticos. Infestações da mosca‑dos‑chifres ocorreram durante todo o período de estudo, com infestações individuais superiores a 100 moscas em todas as contagens, infestações médias mensais de até 183 moscas/vaca e infestações individuais máximas de 500 moscas nas vacas e 1.800 moscas no touro. Influenciados pela influência microclimática de grandes açudes, a mosca-dos-chifres apresentou comportamento bimodal, com picos populacionais anuais em outubro/novembro e março. Não foi encontrada correlação significativa entre fatores climáticos e resultados das contagens. De modo a evitar os picos de infestação e reduzir perdas econômicas subsequentes, medidas de controle são recomendadas.
#2 - Dog and cat population dynamics in an urban area: evaluation of a birth control strategy
Abstract in English:
For canine and feline population management in an urban area, a set of well-developed strategies is required to prevent overpopulation, the abandonment of animals, and zoonosis. An understanding of the dynamics of these populations and a characterization of these populations are necessary for action planning. The proposed strategies should be monitored and evaluated so that canine and feline population management programs are properly implemented. Population management programs can be improved through evidence based adaptive management. The objective of this study was to characterize the canine and feline populations and their dynamics in an urban area and to evaluate the impact of a birth control program. Three cross-sectional census surveys and a birth control program were conducted in a neighborhood of São Paulo area with 4,275 households. The two first surveys were performed in 2005 and 2006, prior to implementation of the birth control program, and were used to characterize the canine and feline populations. The third survey was performed in 2008, eighteen months after the birth control strategy had been established. The canine population decreased from 2006 to 2008, after birth control. The mean age for the canine population was 3.36 years; 65% of the dogs were younger than 3 years of age. The mean life expectancy at birth was 3.9 years for male dogs and 5.9 years for female dogs. The mean age for the feline population was 1.66 years; 74% of the cats were 1 year of age or less. The canine and feline populations had a high mortality rate for juveniles younger than 1 year of age. There was an 8% and an 18% decrease in canine and feline birth rates, respectively, after spay or neuter intervention. There was a high animal population turnover, which was more pronounced in the feline population.
Abstract in Portuguese:
Para o manejo populacional canino e felino em área urbana, um conjunto de estratégias é necessário para evitar a superpopulação, o abandono animal e a transmissão de zoonoses. O entendimento da dinâmica e a caracterização dessas populações são fundamentais para o planejamento das ações, monitoramento e avaliação do programa de manejo populacional e de suas estratégias. Programas de manejo populacional podem ser melhorados por meio de uma gestão adaptativa baseada em evidências. Para avaliar o impacto do controle reprodutivo de cães e gatos foram feitos três estudos transversais por meio de censos em uma área de São Paulo com 4.275 famílias. Os dois primeiros censos foram realizados em 2005 e 2006, antes do controle reprodutivo, e usado para caracterizar as populações canina e felina. O terceiro censo foi realizada em 2008, 18 meses após a estratégia de controle reprodutivo ter iniciado. A população canina diminuiu de 2006 a 2008, após o controle reprodutivo. A idade média para a população canina foi 3,36 anos. A expectativa de vida média ao nascer foi de 3,9 anos para os cães machos e 5,9 anos para as fêmeas. A idade média da população felina foi de 1,66 anos. 65% dos cães eram menores de 3 anos de idade e 74% dos gatos tinham 1 ano de idade ou menos. As populações canina e felina tiveram alta taxa de mortalidade de animais jovens. Houve uma diminuição de 8% e 18% nas taxas de natalidade canina e felina, respectivamente, após a intervenção do controle reprodutivo. Houve uma elevada renovação da população animal, mais pronunciada para a população felina.
#3 - Sazonalidade de Haematobia irritans no Brasil Central
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.
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.
