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Le popolazioni di galliformi alpini e di lepre bianca in Val Brembana (Bergamo). Parte seconda: analisi specialistiche.
No full textRelation between parasites, reproductive index and habitat change in Rock Partridge (Alectoris graeca) populations in the central Southern Alps.
Full text linkRelation between parasites, reproductive index and habitat change in
Rock Partridge (Alectoris graeca) populations in the central southern
alps.
FABRO C.1, VISINTIN A.1, FILACORDA S.1, FRANGIPANE DI REGALBONO A.2, ARTUSO I.3
1Department of Agriculture and Environmental Sciences – University of Udine
2Department of Experimental Veterinary Science- University of Padua
3Comprensorio Alpino N°1 Val Brembana Hunting district
Within the hunting district of Val Brembana the presence of parasites along the intestinal tract
in 60 individuals (32 adults and 22 juveniles, 6 indeterminate) has been studied and correlated
to the reproductive indexes (R.I, measured on 3 and 6 years) of Rock Partridges Alectoris graeca
saxatilis in 6 different sectors and the habitat change. Within these sectors the coverage (%) of
several environmental classes in different sample areas has been identified through photo
interpretation over a time interval of 25 years. In the whole area a high spread of the nematode
Ascaridia was observed and high values of prevalence (P = 69.49%) and mean abundance (MA
= 15.21) have been found, while the presence of genus Capillaria was low with MA = 0.17 and P
= 13.56%. Heterakis was isolated in 33.90% of the Rock Partridges, with MA = 1.45. For Ascaridia
and Heterakis the relationship between variance and mean abundance (s2/MA) was
significantly greater than one (Ascarids = 48.94; Heterakis: 7.90) and the aggregation index k (s2
/ (s2-MA) ) was very close to zero, proving that these parasites show a highly aggregated
distribution within host populations. When analyzing separately the 2 age classes there
seemed to be no significant difference in parasitic infection susceptibility between juveniles (P
= 95.45%) and adults (P = 84.95%). Only MA and P of Heterakis in different sectors was
negatively correlated to a change in reproductive success, both in short and medium term,
while the sectors with the greatest MA of Ascaridia, both in short and medium term, showed
the highest mean reproductive rates and the sectors with the highest k of Capillaria had the
highest R.I. The presence of parasites and particularly the value of MA of Capillaria and the
average total number of parasites seemed to increase with the decreasing of open areas
(coverage) in the different sectors of the study area, as well as with the decreasing of this
observed coverage throughout the 25 year period. A negative correlation between open areas
and the s2/AM ratio was discovered to be very clear. The presence of open areas seemed to
affect significantly the abundance of parasites that in turn seemed to only partially drive R.I
changes. The research was supported by Comprensorio Alpino N° 1 Val Brembana Hunting
district
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Investigation of compost-mulch in the vineyards of Trentino: effects on the soil and culture
No full textRelazione tra indici riproduttivi del fagiano di monte, parassiti e caratteristiche ambientali
No full textVariabilità del successo riproduttivo del Fagiano di monte Tetrao tetrix tetrix e Coturnice Alectoris greca asxatilis in Val Brembana
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