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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Rasprostranjenost Haemosporidia u populacijama migratornih i sedentarnih vrsta ptica pevačica (Passeriformes) u Srbiji / Distribution of Haemosporidia in population of migratory and sedentary passerine birds (Passeriformes) in Serbia

Stanković Daliborka 27 September 2018 (has links)
<p>Hemosporidije&nbsp; kao&nbsp; krvno&nbsp; prenosivi&nbsp; paraziti, veoma su rasprostranjeni u populacijama ptica &scaron;irom&nbsp; planete.&nbsp; Izazivaju&nbsp; avijarnu&nbsp; malariju&nbsp; ili stanje&nbsp; slično&nbsp; njoj,&nbsp; a&nbsp; prenose&nbsp; se&nbsp; preko insekatskih&nbsp; vektora.&nbsp; Hemosporidije&nbsp; su&nbsp; veoma dobro&nbsp; proučene&nbsp; u&nbsp; severnoj&nbsp; i&nbsp; zapanoj&nbsp; Evropi&nbsp; i Severnoj&nbsp; Americi.&nbsp; S&nbsp; obzirom&nbsp; da&nbsp; su hemosporidije&nbsp; slabije&nbsp; izučavane&nbsp; u Palearktičkom&nbsp; migratornom&nbsp; sistemu&nbsp; zapadnog Balkana, osnovni cilj bio je da se istraži koje su vrste&nbsp; tri&nbsp; ispitivana&nbsp; roda&nbsp; hemosporidija <em>Plasmodium</em>,&nbsp; <em>Haemoproteus&nbsp;</em> i<em>&nbsp; Leucocytozoon</em> zastupljene&nbsp; kod&nbsp; različitih&nbsp; migratornih&nbsp; grupa ptica&nbsp; pevačica&nbsp; u&nbsp; Srbiji.&nbsp; Rasprostranjenje,prevalenca&nbsp; i&nbsp; parazitemija&nbsp; ustanovljene&nbsp; su&nbsp; na dva načina: pregledanjem krvnih razmaza ptica i&nbsp; pomoću&nbsp; molekularne&nbsp; (PCR)&nbsp; metode. Sakupljeno&nbsp; je&nbsp; 202&nbsp; uzorka&nbsp; krvi&nbsp; sa&nbsp; sedam lokaliteta.&nbsp; Zaraza&nbsp; rodovima <em>Plasmodium,Haemoproteus</em>&nbsp; i&nbsp; <em>Leucocytozoon</em>&nbsp; ustanovljena je kod&nbsp; 66&nbsp; jedinki,&nbsp; sa&nbsp; ukupnom&nbsp; prevalencom&nbsp; od 32,7%.&nbsp; Najče&scaron;ći&nbsp; rod&nbsp; hemosporidija&nbsp; bilo&nbsp; je <em>Haemoproteus</em>&nbsp; sa&nbsp; prevalencom&nbsp; od&nbsp; 26,1%.&nbsp; Sve zaražene&nbsp; ptice&nbsp; bile&nbsp; su&nbsp; adultne.&nbsp; Samo&nbsp; je&nbsp; jedna ptica&nbsp; imala&nbsp; ko-infekciju.&nbsp; Ustanovljena&nbsp; je&nbsp; 31 loza,&nbsp; od&nbsp; čega&nbsp; su&nbsp; dve&nbsp; potpuno&nbsp; nove&nbsp; i neotkrivene&nbsp; do&nbsp; sada.&nbsp; Loza&nbsp; CCF25&nbsp; iz&nbsp; roda <em>Plasmodium,</em>&nbsp; izolovana&nbsp; je&nbsp; kod&nbsp; obične&nbsp; zebe (<em>Fringilla&nbsp; coelebs)</em>,&nbsp; a&nbsp; dok&nbsp; ORIORI04&nbsp; pripada rodu&nbsp; <em>Leucocytozoon</em>&nbsp; i&nbsp; izolovana&nbsp; je&nbsp; kod vuge(<em>Oriolus&nbsp; oriolus</em>).&nbsp; Loza&nbsp; GRW06<br />(<em>Plasmodium&nbsp; elongatum)&nbsp;</em> izolovana&nbsp; je&nbsp; po&nbsp; prvi put&nbsp; kod&nbsp; obične&nbsp; zebe,&nbsp; dok&nbsp; su&nbsp; loze&nbsp; PARUS20&nbsp; i PARUS25&nbsp; (<em>Leucocytozoon&nbsp; sp</em>.)&nbsp; po&nbsp; prvi&nbsp; put zabeležene&nbsp; kod&nbsp; planinske&nbsp; sive&nbsp; (<em>Poecile montanus)</em>&nbsp; i&nbsp; ćubaste&nbsp; senice&nbsp; (<em>Lophophanes cristatus)</em>.&nbsp; Većina&nbsp; ptica&nbsp; (29)&nbsp; imala&nbsp; je&nbsp; srednji nivo&nbsp; parazitemije.&nbsp; Ustanovljena&nbsp; je&nbsp; značajna razlika&nbsp; u&nbsp; prevalenci&nbsp; između&nbsp; stanarica&nbsp; i delimičnih&nbsp; selica.&nbsp; Razlika&nbsp; u&nbsp; srednjoj parazitemiji bila&nbsp; je&nbsp; značajna&nbsp; takođe&nbsp; između stanarica i delimičnih selica.</p> / <p>Avian&nbsp; haemosporidians&nbsp; are&nbsp; vector-transmitted blood&nbsp; parasites&nbsp; distributed&nbsp; worldwide,&nbsp; abundant in&nbsp; many&nbsp; bird&nbsp; families&nbsp; and&nbsp; well-studied&nbsp; across Europe and&nbsp; North&nbsp; America.&nbsp; Since&nbsp; avian&nbsp; hemosporidians&nbsp; were&nbsp; poorly&nbsp; examined&nbsp; in&nbsp; the Palearctic&nbsp; migratory&nbsp; flyways&nbsp; of&nbsp; the&nbsp; Western Balkans, the goal of this study was to&nbsp; investigate what&nbsp; species&nbsp; of&nbsp; three&nbsp; haemosporidian&nbsp; genera<em> Plasmodium,</em>&nbsp; <em>Haemoproteus</em>&nbsp; and&nbsp;<em> Leucocytozoon</em> infect&nbsp; both&nbsp; resident&nbsp; and&nbsp; migratory&nbsp; passerine birds in Serbia. The&nbsp; prevalence, distribution and parasitemia&nbsp; of&nbsp; avian&nbsp;&nbsp; haemosporidian&nbsp; infections were&nbsp; screened&nbsp; using&nbsp; both&nbsp; nested&nbsp; PCR&nbsp; method and microscopy observation. Out of 202 sampled birds&nbsp; at&nbsp; seven&nbsp; localities,&nbsp; 66&nbsp; were&nbsp; positive&nbsp; for haemosporidians.&nbsp; Total&nbsp; prevalence&nbsp; was&nbsp; 32.7%. Great majority of infected birds (29 individuals) had&nbsp; moderate&nbsp; level&nbsp; of&nbsp; parasitemia.&nbsp; The&nbsp; most abundant&nbsp; haemosporidian&nbsp; genus&nbsp; was Haemoproteus&nbsp; with&nbsp; prevalence&nbsp; of&nbsp; 26.1%.&nbsp;&nbsp;&nbsp; All infected&nbsp; birds&nbsp; were&nbsp; adults,&nbsp; whereas&nbsp; none&nbsp; of tested&nbsp; juveniles&nbsp; were&nbsp; infected.&nbsp; Mixed&nbsp; infection was recorded only in one bird. We identified 31 genetic&nbsp; lineages&nbsp; of&nbsp; haemosporidian&nbsp; parasites. Two new cytochrome&nbsp; b&nbsp; lineages of&nbsp; <em>Plasmodium</em> and&nbsp;<em> Leucocytozoon</em>&nbsp; were identified and found in hosts Common Chaffinch (<em>Fringilla coelebs</em>) and Golden&nbsp; Oriole&nbsp; (<em>Oriolus&nbsp; oriolus)</em>.&nbsp; We&nbsp; identified three&nbsp; new&nbsp; host&nbsp; records&nbsp; for&nbsp; previously&nbsp; known lineages.&nbsp; The&nbsp; lineage&nbsp; GRW06&nbsp; (<em>Plasmodium elongatum</em>)&nbsp; occurred&nbsp; in&nbsp; Common&nbsp; Chaffinch, while&nbsp; the&nbsp; lineages&nbsp; PARUS20&nbsp; and&nbsp; PARUS25 (<em>Leucocytozoon sp</em>.) were recorded in Willow Tit (<em>Poecile&nbsp;</em> <em>montanus</em>)&nbsp; and&nbsp; Crested&nbsp; Tit (<em>Lophophanes cristatus)</em>,&nbsp; respectively. We found statistically&nbsp; significant&nbsp; differences&nbsp; in&nbsp; the prevalence&nbsp; of&nbsp; three&nbsp; haemosporidian&nbsp; genera among resident and partial migratory birds.&nbsp; The difference&nbsp; in&nbsp; mean&nbsp; parasitemia&nbsp; was&nbsp; significant only between resident and partial migrants.</p>
2

A Survey for Leucocytozoon Simondi Mathis and Leger (1910) in Canada Geese of the Malheur Wildlife Refuge

Snively, John Val 01 January 1973 (has links)
Blood smears of blood collected in 1971 and 1972 from 291 Canada geese at Malheur National Wildlife Refuge were examined to determine the incidence of the avian malarial parasite, Leucocytozoon simondi. No parasites were found. Absence of blood parasites suggests that birds using migration routes to the north and northeast of Malheur are free of the disease. The Leucocytozoon infections known in California waterfowl may be attributable to sources within the flyway east or northeast of California, to infected birds crossing over from other flyways, or abnormal conditions in the molting grounds of sub-adult and non-nesting birds where major flyways converge in northcentral Canada.
3

Presencia de Leucocytozoon smithi en pavos de engorde de crianza comercial del departamento de Lima

Lazo Palomino, Anlly Dessire January 2007 (has links)
Manifesta que la leucocitozoonosis de los pavos es una enfermedad producida por el protozoo Leucocytozoon smithi y se caracteriza por producir grandes pérdidas económicas en la industria avícola. El ciclo de vida del hemoparásito comprende el desarrollo de la esquizogonia en los tejidos del ave, la gametogonia en las células sanguíneas y la fecundación y esporogonia en el artrópodo vector. El objetivo del presente trabajo fue demostrar la presencia de las formas gametogónicas del Leucocytozoon smithi en pavos procedentes de granjas comerciales del departamento de Lima. Para tal efecto se tomaron muestras de sangre de 346 pavos aparentemente sanos procedentes de once granjas comerciales. Se muestrearon animales entre de 1 a 17 semanas durante los meses de Octubre a Noviembre del 2005. Se prepararon dos frotis de sangre por pavo los que fueron coloreados con tinción Giemsa y observados al microscopio simple (100X). No se observaron gametocitos de L. smithi en ninguno de los frotis examinados concluyéndose que el parásito no se encuentra presente en poblaciones aparentemente sanas y de estarlo lo esta en una prevalencia menor al 1%. / Tesis
4

Adaptive molecular evolution and biodiversity in malaria parasites

Bodden, Haley Nicole 10 August 2018 (has links)
Haemosporidian parasites are the agents of malaria. Countless vertebrates are affected by haemosporidians each year. Haemosporidians have been shown to be evolving at rapid rates; leading to new species of haemosporidians being discovered and new host associations being made. Adaptive molecular evolution was detected in an important hemoglobin degradation gene, falcilysin. At multiple sites across multiple genes involved in important functions signatures of negative selection were detected. The signatures of selection across non-hemoglobin degradation genes were indicative of evolutionary conservation when compared to the more variable hemoglobin degradation genes. This is probably due to the important role the hemoglobin degradation genes play in haemosporidian metabolism. A survey of local passerines detected a parasite prevalence rate of 57%. This included three genera of haemosporidians detected across six lineages and two more distantly related sequences. Leucocytozoon was detected for the first time in Mississippi songbirds, indicating the importance of surveying for understanding haemosporidian evolution and range.
5

Indirect effects of river regulation : consequences for landbirds of reduced numbers of aquatic insects

Strasevicius, Darius January 2007 (has links)
<p>Abstrakt: Jag har undersökt hur älvreglering påverkar mängden knott (Tvåvingar: <i>Simuliidae</i>) längs flera norrlandsälvar och vilka konsekvenser denna påverkan får för den landlevande fågelfaunan. Studien visar att utbyggnad av älvar har en negativ effekt på mängden knott. Det fanns sju gånger högre tätheter av knott längs "orörda älvar" jämfört med utbyggda älvar.</p><p>Skillnaden i antal knott mellan älvtyperna var mycket större för knotthanar än för knotthonor, vilket förklaras av att honorna är rörligare eftersom de flyger och letar efter blod. Knott lever av blod från ett flertal däggdjur och fåglar och visar en stor variation i värd-specificitet mellan olika arter. Jag fann en högre frekvens av haemosporida blod parasiter (<i>Leucocytozoon</i>) i fåglar längs "orörda" Vindelälven jämfört med den reglerade Umeälven. Detta mönster stämmer väl överens med tätheten fågelparasiterande knott som är lägre längs Umeälven. Knott attackerade främst värdar som var stora och vanliga. Fågelsamhällets sammansättning skiljde sig mellan orörda och utbyggda älvdalar. Tätheten av icke insektsätande fåglar tenderade att minska, efter häcksäsongen, längs orörda älvar medan den ökade längs utbyggda älvar. Den insektsätande fågeln svartvit flugsnappare (<i>Ficedula hypoleuca Pallas</i>) uppvisade större häckningsframgång längs orörda älvar jämfört med utbyggda älvar. Detta är förmodligen en effekt av den större mängden insekter som finns längs orörda älvar.</p> / <p>The effects of river regulation on blackfly (Diptera: <i>Simuliidae</i>) abundances and consequences for the avifauna in terrestrial environments were studied along multiple rivers in northern Sweden. I found that impoundment of rivers has detrimental effect to blackfly abundances. The densities of large-river breeding blackfly species were several-fold higher along free-flowing than along regulated rivers. The difference in abundances was much larger in males than blood-seeking females. Blackflies attacked a variety of mammalian and avian hosts and showed different levels of host-specificity between species. I found higher prevalence of haemosporidian blood parasites (<i>Leucocytozoon</i>) in birds along the free-flowing Vindel River in comparison to the regulated Ume River, where the lower densities of ornithophilic blackflies were reduced. Blood-seeking blackflies predominantly attacked large and/abundant hosts.</p><p>Assemblages of birds differed between valleys of regulated and free-flowing rivers. Densities of noninsectivorous birds tended to decrease along free-flowing rivers in the post-breeding season, but increased along regulated rivers at the same time. Insectivorous European pied flycatcher (<i>Ficedula hypoleuca Pallas</i>) showed greater fledging success along free-flowing than regulated rivers, which probably reflects the higher insect abundances found along freeflowing rivers.</p>
6

Indirect effects of river regulation : consequences for landbirds of reduced numbers of aquatic insects

Strasevicius, Darius January 2007 (has links)
Abstrakt: Jag har undersökt hur älvreglering påverkar mängden knott (Tvåvingar: Simuliidae) längs flera norrlandsälvar och vilka konsekvenser denna påverkan får för den landlevande fågelfaunan. Studien visar att utbyggnad av älvar har en negativ effekt på mängden knott. Det fanns sju gånger högre tätheter av knott längs "orörda älvar" jämfört med utbyggda älvar. Skillnaden i antal knott mellan älvtyperna var mycket större för knotthanar än för knotthonor, vilket förklaras av att honorna är rörligare eftersom de flyger och letar efter blod. Knott lever av blod från ett flertal däggdjur och fåglar och visar en stor variation i värd-specificitet mellan olika arter. Jag fann en högre frekvens av haemosporida blod parasiter (Leucocytozoon) i fåglar längs "orörda" Vindelälven jämfört med den reglerade Umeälven. Detta mönster stämmer väl överens med tätheten fågelparasiterande knott som är lägre längs Umeälven. Knott attackerade främst värdar som var stora och vanliga. Fågelsamhällets sammansättning skiljde sig mellan orörda och utbyggda älvdalar. Tätheten av icke insektsätande fåglar tenderade att minska, efter häcksäsongen, längs orörda älvar medan den ökade längs utbyggda älvar. Den insektsätande fågeln svartvit flugsnappare (Ficedula hypoleuca Pallas) uppvisade större häckningsframgång längs orörda älvar jämfört med utbyggda älvar. Detta är förmodligen en effekt av den större mängden insekter som finns längs orörda älvar. / The effects of river regulation on blackfly (Diptera: Simuliidae) abundances and consequences for the avifauna in terrestrial environments were studied along multiple rivers in northern Sweden. I found that impoundment of rivers has detrimental effect to blackfly abundances. The densities of large-river breeding blackfly species were several-fold higher along free-flowing than along regulated rivers. The difference in abundances was much larger in males than blood-seeking females. Blackflies attacked a variety of mammalian and avian hosts and showed different levels of host-specificity between species. I found higher prevalence of haemosporidian blood parasites (Leucocytozoon) in birds along the free-flowing Vindel River in comparison to the regulated Ume River, where the lower densities of ornithophilic blackflies were reduced. Blood-seeking blackflies predominantly attacked large and/abundant hosts. Assemblages of birds differed between valleys of regulated and free-flowing rivers. Densities of noninsectivorous birds tended to decrease along free-flowing rivers in the post-breeding season, but increased along regulated rivers at the same time. Insectivorous European pied flycatcher (Ficedula hypoleuca Pallas) showed greater fledging success along free-flowing than regulated rivers, which probably reflects the higher insect abundances found along freeflowing rivers.

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