PDF superior Avian Influenza Infection Dynamics in Minor Avian Species

Avian Influenza Infection Dynamics in Minor Avian Species

Avian Influenza Infection Dynamics in Minor Avian Species

Necropsies and tissue sampling were performed according to standard protocols [37]. After fixation in 10% neutral buffered formalin and embedding in paraffin, tissue sections were processed routinely for hematoxylin/eosin (HE) staining. The following tissues were examined: esophagus, crop, proventriculus, gizzard, duodenum, jejunum-ileum, cecum/cecal tonsil, colon, rectum, pancreas, liver, kidney, adrenal gland, gonad, nasal turbinates, trachea, lung, heart, breast muscle, skin, bone marrow, spleen, bursa of Fabricius, thymus, brain, spinal cord, and sciatic nerve. In addition, an immunohistochemical (IHC) technique was performed as previously described [38,39]. The primary antibody was a mouse-derived monoclonal commercial antibody against nucleoprotein (NP) of influenza A virus (IgG2a, Hb65, ATCC). As a secondary antibody, a biotinylated goat anti-mouse IgG antibody (GaMb, Dako E0433, Glostrup, Denmark) was used. Tissues previously demonstrated to be positive against NP of influenza A virus by IHC were used as a positive control. Duplicated samples of all animals incubated without the primary antibody, as well as tissues from sham- inoculated animals processed as usual by IHC, served as negative controls. The following score was used to grade the staining in the tissues: no positive cells (−), single positive cells (+), scattered groups of positive cells (++), widespread positivity (+++).
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225 Lee mas

STRP draft Resolution and guidance on Highly Pathogenic Avian Influenza (HPAI)

STRP draft Resolution and guidance on Highly Pathogenic Avian Influenza (HPAI)

Avian influenza is a widespread disease, which occurs naturally within some waterbird species. The spread of infection with these viruses to a range of other species, including humans, is well- known. The emergence and spread of highly pathogenic avian influenza H5N1 of Asian lineage (HPAI H5N1) since 2003 has been historically unprecedented both in the extent of geographical range of the virus and its high pathogenicity to wild birds (as opposed to only domestic birds). It has had major impacts on rural livelihoods linked to the keeping of domestic birds (mainly chickens, ducks, turkeys, ostrich and quail) and on nature conservation, including mortality of waterbirds at many Ramsar sites. There have also been major concerns as to the potential for viral change that might precipitate a human influenza pandemic given the high mortality rate of people who have become infected with H5N1.
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54 Lee mas

Avian influenza in Latin America: A systematic review of serological and molecular studies from 2000 2015

Avian influenza in Latin America: A systematic review of serological and molecular studies from 2000 2015

Avian influenza or bird flu is a highly contagious acute viral disease that can occur in epi- demics and cross-border forms in poultry and wild birds. The characteristics of avian influ- enza viruses (AIVs) allow the emergence of new viral variants, some with zoonotic and pandemic potential. AIVs have been identified in Latin America; however, there is a lack of understanding of these viruses at the regional level. We performed a systematic literature review on serological or molecular evidence of AIVs circulation in Latin America. Methods were designed based on the PRISMA and STROME guidelines. Only peer-reviewed studies published between 2000 to 2015 and data was analysed based on country, viral subtype, avian species, and phylogenetic origins. From 271 studies initially found only twenty-six met our inclusion criteria. Evidence of AIVs infection was found in most Latin American coun- tries, with Mexico as the country with the largest number of conducted studies and reported cases during the period analysed, followed by Chile and Argentina. Most of the AIVs were early reported through surveillance systems and at least 14 different subtypes of influenza viruses were reported in birds, and the presence of both low (92.9%) and high (7.1%) patho- genic AIVs was shown in Latin America. Of the reported AIVs in Latin America, 43.7% belong to migratory birds, 28.1% to local wild birds, and 28.1% to poultry. The migratory bird population mainly comprises families belonging to the orders Anseriformes and Charadri- formes. We highlight the importance of epidemiological surveillance systems and the possi- ble role of different migratory birds in the transmission of AIVs within the Americas. Our findings demonstrate the limited information on AIVs in Latin America and highlight the need of more studies on AIVs at the regional level, particularly those focused on identifying the endemic subtypes in regional wild birds.
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21 Lee mas

Ramsar COP10 DR 21 Draft Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza H5N1

Ramsar COP10 DR 21 Draft Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza H5N1

26. An agricultural practice that provides ideal conditions for cross-infection and thus genetic change is used on some fish-farms in Asia: battery cages of poultry are placed directly over troughs in pig-pens, which in turn are positioned over fish farms. The poultry waste feeds the pigs, the pig waste is either eaten by the fish or acts as a fertiliser for aquatic fish food, and the pond water is sometimes recycled as drinking water for the pigs and poultry (Greger 2006). These kinds of agricultural practices afford avian influenza viruses, which are spread via the faecal-oral route, a perfect opportunity to cycle through a mammalian species, accumulating the mutations necessary to adapt to mammalian hosts. Thus, as the use of such practices increases, so does the likelihood that new influenza strains infectious to and transmissible between humans will emerge (Culliton 1990; Greger 2006).
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59 Lee mas

Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza

Resolution X.21 Guidance on responding to the continued spread of highly pathogenic avian influenza

26. An agricultural practice that provides ideal conditions for cross-infection and thus genetic change is used on some fish-farms in Asia: battery cages of poultry are placed directly over troughs in pig-pens, which in turn are positioned over fish farms. The poultry waste feeds the pigs, the pig waste is either eaten by the fish or acts as a fertiliser for aquatic fish food, and the pond water is sometimes recycled as drinking water for the pigs and poultry (Greger 2006). These kinds of agricultural practices afford avian influenza viruses, which are spread via the faecal-oral route, a perfect opportunity to cycle through a mammalian species, accumulating the mutations necessary to adapt to mammalian hosts. Thus, as the use of such practices increases, so does the likelihood that new influenza strains infectious to and transmissible between humans will emerge (Culliton 1990; Greger 2006).
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62 Lee mas

Physiological and biochemical aspects of the avian uropygial gland

Physiological and biochemical aspects of the avian uropygial gland

The chemical composition of the gland secretion has been suggested as a valuable taxonomic tool (Jacob and Grimmer, 1975; Jacob and Ziswiler, 1982; Hoerschelmann and Jacob, 1996). Our results suggest that the gland de- velopmental trend was independent of the bird lineage. Thus, the gland is present in phylogenetically distant birds (e.g. Tinamidae-Hirundinidae) or absent in phylogeneti- cally close taxa (some Psittacidae-Columbidae). Sweeney et al. (2004) showed that the feather wax composition is unlikely to be highly informative for reconstructing phy- logenetic relationships. Levy and Strain (1982) have also noted that the use of the secretion’s chemical composition with chemotaxonomic purposes could be inappropriate considering this a parameter with a large amount of cir- cannual variations associated to bird reproduction cycles, and conditioned by environmental, hormonal and physi- ological factors.
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10 Lee mas

Spatial distribution, prevalence and diversity of haemosporidians in the rufous collared sparrow, Zonotrichia capensis

Spatial distribution, prevalence and diversity of haemosporidians in the rufous collared sparrow, Zonotrichia capensis

One Haemoproteus haplotype (H15) was found in the austral region in Chile, and in northern countries (Peru, Ecuador, Colombia and Costa Rica), but was absent in the remaining sampled areas. This odd disjunction might be caused by avian migration, especially as the southern- most portion of Chile that corresponds to an overlap be- tween two main migratory routes between the Northern and Southern Hemispheres [59]. Furthermore, bird mi- gration has contributed to the wide distribution of haemosporidian parasites [1]. A major biogeographical boundary for avian species in South America is the Andes Mountains [60, 61]. Although results from our BAPs analysis (Fig. 5) grouped the samples from Argentina with the northern clade, there is a clear dis- tinction in haplotype distribution between regions with a higher frequency of the haplotype H14. For Plasmodium , a distinct clade, consistent with results from BAPs that show Argentina, Uruguay, Brazil and Bolivia (Fig. 5) grouped together, supports the notion that the Andean massif limits gene flow in these parasites. Such assertions are preliminary and sampling of a greater geographical intensity is required for the eastern part of the Andes. Limited genealogical structure in Plasmodium across the remaining studied locations might be associated with a tendency towards host-parasite generalists with marked gene flow among different hosts, but this might also be a consequence of relatively low sample sizes, again meriting further study with larger arrays of samples.
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12 Lee mas

Evaluacin de la capacidad inmunognica y protectora de antgenos de Pasteurella multocida, obtenidos de aislados de casos clnicos

Evaluacin de la capacidad inmunognica y protectora de antgenos de Pasteurella multocida, obtenidos de aislados de casos clnicos

The immunogenic protection response to four P. multocida isolations obtained from clinical cases and a reference strain was studied. Isolations were proven as three different immunogens: complete antigen (Ag), washed Ag and culture supernatant. They were subcutaneously administered in SPF light White Leghorn hens. Immune response was evaluated using ELISA test and challenge test evaluated protection response. The ANOVA and Tukey test did not show statistical differences between groups. All isolations using different vaccines induced high protection levels ranging from 87 to 100%. This study indicates that immuniza- tion using these three immunogens induce an effective response against P. multocida challenge with the best protection when culture supernatant is used.
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10 Lee mas

Evaluation of the solar contribution in a hybrid incubator of avian eggs

Evaluation of the solar contribution in a hybrid incubator of avian eggs

The farm where the system was installed and evaluated was established in 1998, it is a complete-cycle farm with 692 pairs in the breeding flock that is maintained by the yearly substitution of the eldest 1/3 of the flock, thus being composed by 1/3 of one year old, 1/3 of two years old and 1/3 of three years old partridge pairs laying eggs from the end of February to the beginning of June incubating 24000 eggs on average per season with 54% of hatchability. The eggs are stored from one to 21 days prior to incubation at temperatures ranging from 10º C to 15° C. This small-scale farm was established in a period where most of the new established farms have switched to a more industrial production structure either with an increase of their breeding flocks or by eliminating them and focus on the chicks growing. 2.2 Factory design of the incubator and modified solar-electric hybrid design
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14 Lee mas

Los jueces de las querellas

Los jueces de las querellas

ABSTRACT: In this paper I analyze how the so called “judges of complaints” worked on the Granada frontier. This magistracy has been studied from a local point of view since 1948. The diplomatic agreements between Castile and Granada provide the best primary sources in establishing how both polities were interested in maintaining peace after a truce was signed. It is not yet clear when these judges acted for the first time. They were not ap- pointed to suppress violence in the frontier, but to control it. This is the reason why they en- joyed the privilege to retaliate. The judges, both Christian and Muslim, worked in their own way. We must not mix them up with other judges that on certain occasions met to mediate in conflicts. Modern historians are inclined to minimize the role played by these judges of
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29 Lee mas

Anlisis del genoma de un virus atpico de influenza aviar H5N2 de baja patogenicidad de origen mexicano

Anlisis del genoma de un virus atpico de influenza aviar H5N2 de baja patogenicidad de origen mexicano

Since December 1994, when the high- and low-pathogenic H5N2 avian in- fluenza viruses were isolated in Mexico, an avian influenza vaccination campaign was established as part of an eradication programme that used inactivated, emulsi- fied, and recombinant pox-avian influenza vaccines. However, only the high-patho- genic avian influenza (HPAI) was eradicated (Villarreal-Chavez and Rivera-Cruz, 2003). Since then, LPAI has been controlled by the officially authorized virus strain A/Ck/México/CPA-232/1994 (H5N2), which is a unique case of long-term mas- sive vaccination of poultry in Mexico. However, major antigenic differences be- tween isolates have been reported through haemogglutination inhibition and virus neutralization tests from viruses isolated between the years of 1993–2002 and 1994–2008, compared to the virus strain A/Ck/México/CPA-232/1994 (H5N2), which suggest that the vaccine does not protect and allows for the circulation of LPAI viruses in specific regions of Mexico (Lee et al., 2004; Escorcia et al., 2010; Armas et al., 2015). Additionally, LPAI virus (H5N2) isolates from chickens in Mexico were genetically closely related to LPAI virus (H5N2) isolates from outbreaks in Taiwan (Chang-Chun et al., 2014) and Central America (Okamatsu et al., 2007).
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18 Lee mas

Avian invasions: from basic to applied research

Avian invasions: from basic to applied research

Despite the central importance of niche opportunities, the competitive ability could also play a role in the success of Leiothrix in Collserola. The arrival of Leiothrix in the community coincided with a decline of the native species with which overlaps in the niche to a greatest extent, the Blackcap. The decline of Blackcaps did not seem to be caused by environmental changes, as no similar declines were observed in habitats where the invader was absent. The alternative is that the Blackcap suffered from competition with the invader, a possibility that receives credence from the great niche overlap between both species. Indeed, Leiothrix has suggested to have caused similar declines of native species in other regions where the species is invading natural habitats (Sato 2006). Although we found no evidence of agonistic encounters between Leiothrixs and Blackcaps, this does not exclude a role for contest competition. This is because contest competition may lead to avoidance behaviors, which may reduce the frequency of encounters. Leiothrix was larger in size and flocked in larger groups than blackcaps, which would have given some competitive advantages. Other mechanisms are also possible, however. One is exploitation competition. Although in general one would expect that native species are better adapted to exploit the local resources than an exotic species, as the former have had more opportunity to adapt locally, this is not necessarily true for generalists. Moreover, as already mentioned, social foraging may help overcome the lack of proficiency in foraging under novel contexts through social learning and skill-pool effects (Liker and Bokony 2009, Rodriguez et al. 2010).
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205 Lee mas

Perfil epidemiológico de la infección por el virus de la influenza A (H1N1) en pacientes de la región Ayacucho, 2009.

Perfil epidemiológico de la infección por el virus de la influenza A (H1N1) en pacientes de la región Ayacucho, 2009.

a) Cuantificar la tasa de letalidad por infection por el virus de la influenza A (H1N1) en pacientes de la Region Ayacucho. b) Identificar el perfil epidemiologico de la infection por e[r]

44 Lee mas

Distribution of the hematozoa of Neotropical birds

Distribution of the hematozoa of Neotropical birds

The data presented in Table 1 was eompiled mainly from primary sourees in the literature and from unpublished reeords in the files of the Intemational Refe­ rence Centre foc Avian Haematozoa. [n sOrne cases, where primary soueces were not available, or were diffieult to interpret, summaries of sueh data have been used (e.g. Calindo and Sousa, [1966] summarized the intemal reports of the Gorgas Memorial Laboratory). Reeords from eheeklists, or publications from which prevalenee (defined herein as the proportion of infected birds to the total sample) eould not be deterrnined, were included to demonstrate the occurrence of a parasite in a parti­ cular avian host when that parasite had not already been reported as a prevalenee record. Such records are indicated by ( + ) in Tables 1 , 2 and 4. The "Other" category in Tables 1 , 2, 3 and 4 ineludes haemogregarines, A toxoplasmaj Lankesterella and Akiba. A few published reeords of avian hematozoans have been omitted as they cite blood parasites of birds of Neotropical origin examined in other eountries. It was not possible to determine whether these birds were infeeted prior to or after importation into the country in which they were examined.
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60 Lee mas

Neotropical dry forest recovery and its impact on the avian community

Neotropical dry forest recovery and its impact on the avian community

Tropical dry forests (TDFs) are considered important sources of biodiversity and species richness given the wide variety of plant and animal species that have adapted to the unique habitats that are found exclusively in TDFs (Gillespie et al., 2000). Lianas are a structural group of plants that have received growing attention for their role in community structure and ecosystem function and are considered a key component of TDF ecosystems (Sánchez-Azofeifa & Castro-Esau, 2006). Lianas are defined as climbing plants that produce woody tissue and germinate on the ground. Eventually, these vines lose their ability to support their own weight and subsequently rely on external supports, such as trees, to aid their ascent into the forest canopy (Gerwing, 2006). As such, they are considered non-structural elements of a given forest. Unlike other plants that slow their growth during the dry season to preserve water, lianas have the competitive advantage of growing during times of drought due to an efficient vascular structure that allows for photosynthesis. As a result, liana abundance is often higher in TDFs than in other tropical forests (Schnitzer, 2005). In disturbed forests, an increase in liana abundance and biomass can help to restore the light environment, microclimatic conditions, and vegetation structure, creating habitat characteristics similar to those of the forest interior and thereby reducing the effects of forest fragmentation on birds (Michel et al., 2014).
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127 Lee mas

Efecto comparativo de la interacción de inmunomoduladores en la productividad de pollos de carne línea cobb avian 48

Efecto comparativo de la interacción de inmunomoduladores en la productividad de pollos de carne línea cobb avian 48

El presente trabajo se llevó a cabo en la granja El Tizal S.A.C., ubicado en Chao provincia de Virú, departamento de La Libertad; en los meses de agosto a octubre del 2014. Para determinar el efecto comparativo de la interacción de inmunomodulador en la productividad de pollos de carne línea Cobb Avian 48. Se evaluaron 400 pollos separados en tratamiento testigo y tratamiento con inmunomodulador. El tratamiento con inmunomodulador tuvo una media total de 2,50 kg de peso final, mientras que el tratamiento testigo tuvo una media de 2,43 kg. No se calcularon diferencias estadísticas significativas (p>0,05) entre las medias de los dos tratamientos. Para el parámetro incremento de peso, el tratamiento con inmunomodulador logró una media total de 2,7 kg, en tanto que el tratamiento testigo obtuvo 2,2 kg. Se determinaron diferencias estadísticas altamente significativas (p<0,01) entre tratamientos Para la característica conversión alimenticia, el tratamiento con inmunomodulador tuvo una media total con un valor de 1,7 y el tratamiento testigo fue de 1,8; determinándose diferencias estadísticas significativas (p<0,05). En cuanto al consumo de alimento, el tratamiento con inmunomodulador tuvo un promedio total de 4,3 kg y el tratamiento testigo fue de 4,2 kg. No se calcularon diferencias estadísticas significativas (p>0,05). En el tratamiento con inmunomodulador se calculó un porcentaje de mortalidad de 6% en tanto que el tratamiento testigo tuvo 5%. No se calcularon diferencias estadísticas significativas (p>0,05).
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65 Lee mas

Notes on avian ectoparasites from Costa Rica  I  Acarina and Diptera

Notes on avian ectoparasites from Costa Rica I Acarina and Diptera

1 have been unable to locate any published records oI. chiggers for Costa Rica. Indeed, the only Central American republic for which information has been surnmarized is Guatemala. BRENNAN and DALMAT ( 1 ) recorded 19 species for this country. More recentIy, BRENNAN and YUNKER (2) listed 76 species of chiggers for Panamá.

7 Lee mas

Los Corregidores de los Duques de Alba (1430 1531)

Los Corregidores de los Duques de Alba (1430 1531)

Otrosy por quanto en la dicha residengia se provo y averiguo quel dicho bachiller y regidores avian pagado de 10s propios de la dicha mi villa tres mill maravedis de alcavala de la carni[r]

28 Lee mas

The importance of riparian habitats for avian communities in a highly human- modified Neotropical landscape

The importance of riparian habitats for avian communities in a highly human- modified Neotropical landscape

Abstract. Intensification of agriculture and urban development are the main forces degrading natural ecosystems, particularly within species-rich countries. In this study, we determined the variation in bird communities between anthropogenic (i. e., cattle grazing lands, crop fields, urban areas) and riparian habitats within a highly human- modified landscape in northwestern Colombia. For this purpose, we assessed differences in bird community diversity, structure, and composition among studied habitats. We also investigated similarities of surveyed habitats according to the habitat preferences of species. Results showed that riparian habitats play a fundamental role in human-dominated landscapes, as they maintain diverse and complex bird communities, support interior forest bird species, and might promote heterogeneous bird communities in nearby habitats. Cattle grazing lands also exhibited heterogeneous bird communities, which might be a result of the presence of tall trees, abundant shrub cover, and proximity of riparian habitats. Few species were over dominant within crop fields and urban areas due to a simple vegetation structure, leading to homogeneous avian communities where disturbed-site species thrive. Given that increasing human population depends on agricultural and urban ecosystems worldwide, there is an urgent need to foster management and conservation activities within such ecosystems to support wildlife and enhance human welfare.
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11 Lee mas

La primera tentativa de Independencia Argentina

La primera tentativa de Independencia Argentina

» «...y despacharon con sus cartas para los susodichos a la dha ciudad de Santa Fé al dho Diego Ruiz e a Pedro de Villalta que avian venido de la ciudad de Santa Fé a tomar la dicha bord[r]

8 Lee mas

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