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The red–legged partridge Alectoris rufa lives in a situation of potential conservation risk for its long–term preservation in Italy as its habitat is increasingly threatened by the disappearance of traditional agriculture–related environments. In such a situation, it is important to use effective and appropriate monitoring methods to assess population changes over time and to identify potential conservation threats. The objective of this study was to evaluate the effectiveness of the playback method to estimate the density of calling males. We compared playback method with spontaneous calling of males at dawn and direct observations along transects. The results on raw count data of playback counts revealed a strong underestimation rate compared to the method that gave the best results: count of spontaneous calls at dawn. Our study provides a critical evaluation of a method that is widely used even though data about its effectiveness are scarce. Our data do not evaluate detection probability of the three methods. Our aim was only to evaluate which methods give the best results in term of population size estimation under the same field condition (same population density, same period, same monitoring area). The results raise some doubts about the ability of the playback method to monitor red–legged partridge populations. The implications of our results for red–legged population management are discussed.

Distance sampling is being extensively used to estimate the abundance of animal populations. Nevertheless, the great variety of ways in which data can be analyzed may limit comparisons due to the lack of standardization of such protocols. In this study, the influence of analytical procedures for distance sampling data on density estimates and their precision was assessed. We have used data from 21 surveys of mountain ungulates in the Iberian Peninsula, France and the Italian Alps. Data from such surveys were analyzed with the program Distance 6.0. Our analyses show that estimated density can be higher for higher levels of data truncation. We also confirm that the estimates tend to be more precise when data are analyzed without binning and without truncating. We found no evidence of size biased sampling as group size and distances were uncorrelated in most of our surveys. Despite distance sampling being a fairly robust methodology, it can be sensitive to some data analysis strategies. [ABSTRACT FROM AUTHOR]

Faecal pellet count is an indirect census method used to estimate the density of an animal population. Factors that affect the accuracy and precision of this method are the defecation rate, the decay time and the detectability of the droppings. In this study, we analysed the influence of some variables on the detectability of droppings: (i) environmental variables, EV (vegetation type, grass height, meteorological conditions); (ii) subjective variables, SV (operator, subjective visibility); (iii) faeces–species related variables, SRV (Capreolus capreolusLinnaeus, 1758;Cervus elaphusLinnaeus, 1758 andLepus europaeusPallas, 1778). The average values of dropping detectability, expressed as percentage of observations from the minimum detectability (0) to the maximum (1), were: 0.99 (SD = 0.07) for red deer faeces; 0.93 (SD = 0.16) for roe deer faeces; 0.89 (SD = 0.21) for European brown hare faeces. The red deer detectability value was statistically higher than the roe deer and European brown hare values (X2 = 26.61, df = 2,p < 0.01). A generalised linear model (GLM) analysis shows that the variables which negatively affect the dropping detectability are different for the three species: (i) vegetation type, especially deciduous forest, for the red deer; (ii) grass height for the European brown hare; (iii) subjective visibility, especially the category “none”, for the roe deer. These results suggest that the characteristics of both the study area and the species considered could affect the detectability of droppings, and therefore also the entire estimation density. So, faecal pellet count monitoring programmes should carefully take into account the environmental characteristics and should be performed when detectability is maximised (e.g. short grass, fewer leaves, less undergrowth). [ABSTRACT FROM AUTHOR]

This study provides insights about the diversity, prevalence and distribution of alpine wild galliformes gastrointestinal parasite community, trying to fill a gap in the scientific information currently available in scientific literature. The analysis included three host species: 77 rock partridge (Alectoris graeca saxatilis), 83 black grouse (Tetrao tetrix tetrix) and 26 rock ptarmigan (Lagopus muta helveticus) shot during the hunting seasons 2008-2015. Parasites isolated were Ascaridia compar, Capillaria caudinflata and cestodes. The rock ptarmigan was free from gastrointestinal parasites, whereas the most prevalent helminth (37%) was A. compar in both black grouse and rock partridge. C. caudinflata occurrence was significantly higher in black grouse (prevalence = 10%, mean abundance = 0.6 parasites/sampled animal) than in rock partridge (prevalence = 1.20%, mean abundance = 0.01 parasites/sampled animal). Significant differences were detected among hunting districts. A. compar was found with a significant higher degree of infestation in the hunting districts in the northern part of the study area whereas cestodes abundance was higher in Lanzo Valley. Quantitative analysis of risk factors was carried out using a generalized linear model (GLM) only on the most common parasite (A. compar). Latitude was the only factors associated with infestation risk (OR = 52.4). This study provides information on the composition and variability of the parasite community in the alpine Galliformes species.

Wild mosquitoes were allowed to feed, during two nights, on a heartworm-infected dog with a very high microfilaraemia (72,000 and 78,000 microfilariae/ml just prior to be allocated in the live trap). A heartworm-free dog was used as control bait in the second night. Engorged mosquitoes (Aedes caspius, Anopheles maculipennis s.l., Culex modestus, and Cx pipiens) were kept under laboratory conditions, artificially fed until day 10 post-infection (PI) and then dissected for the presence of Dirofilaria immitis larvae. Mortality of Ae. caspius and Cx modestus was significantly higher than controls on day 3 PI (89.4 and 80.3%, respectively), but survival rates were similar in the following period. Third-stage larvae were observed from day 12 to 17 PI in the four mosquito species studied. However, vector efficiency was significantly higher in Ae. caspius which produced 102 (73.9%) of the 138 infective larvae found. Although less efficient vectors, the other 3 species may contribute to D. immitis transmission in the study area due to their abundance (Cx modestus) or higher resistance to the negative effects of infection (An. maculipennis s.l., Cx pipiens). As far as Cx pipiens is concerned, this mosquito, which luckily fed the least frequently on the dog, confirmed to act as powerful vector in iperendemic areas. The risks for veterinary and medical health, related to the zoo-antropophylic host-feeding pattern of the studied species, are discussed.

Two cases of haemonchosis occurred in the Spanish ibex (Capra pyrenaica) population of the National Hunting Reserve of Tortosa and Beseit, northeastern Spain, in July 1992 and May 1993. The animals were cachectic and recumbent and had an acute hemorrhagic, macrocytic and hypochromic anemia; which was related to a high infection of 2,016 and 1,863 Haemonchus contortus, respectively, in the abomasum of the animals.

Sarcoptic mange is the most severe infection in chamois in the Eastern Alps. This study analyses and discusses data from two mange foci in the Foresta Demaniale di Tarvisio (NE Italy). The first impact of mange on naive host populations was dramatic, with mortality rates of over 80%. The chamois herds were decimated, but they recovered quite fast and two later epizootics were observed to have a far less severe impact on the chamois population. Intervals between successive waves lasted 10 to 15 years. No sign of low reproductive performance nor evidence of a poor physical condition of the animals was observed in the years preceding the new epizootic waves. Mortality rates were only slightly influenced by the density of the host population. In a long lasting focus of disease, adult males appeared more vulnerable to mange than other sex and age classes. Cases of mange were also more frequent in winter and spring. This seasonal trend may be explained by the interaction between the dynamics of mites, ethological patterns-rut activity-and the poorer physical condition of the host during this period.

The following study records ten years' experience in the control of Fascioloides magna infection in a fenced area grazed by an overdense red deer population together with free-ranging cattle. During the winter 1977/78 mortality due to a "fascioloidosis-malnutrition syndrome" reduced the deer stock almost by half. Control measures were aimed at combatting the fluke in the wild definitive host by the administration of medicated pellets. Four flukicides were used over the years: rafoxanide, diamphenetide, oxyclozanide and triclabendazole. Efforts were also made to control the number of deer and to improve their condition by artificial feeding during the winter months. Intervention on the habitat of the intermediate hosts of F. magna were purposely avoided. The efficacy of this programme was evaluated by both copromicroscopic examinations and fluke counts from the livers of the wild and domestic macromammals living in the study area. Some yield parameters of the deer population were also taken into account. Results demonstrate that F. magna infection, though a hazard for cattle productivity, remained a deer problem when pharmacological prophylaxis was regularly applied.

Sporocysts of Sarcocystis sp. from dogs fed with ibex meat were orally inoculated into kids and lambs. Three kids, given 4 x 10(6) and 4 x 10(4) sporocysts, respectively, died from acute sarcocystosis. Schizonts, though found in all the tissues of these kids, were particularly numerous in the kidneys, brain and spinal cord. Another three kids inoculated with 5 x 10(3) sporocysts and two lambs, inoculated with 1 x 10(6) and 5 x 10(3) sporocysts, respectively, showed no clinical signs and were sacrificed between 111 and 130 days after infection. Mature sarcocysts were found both in the heart and striated muscles of these animals. No parasitic stage was found in two kids and two lambs used as uninoculated controls. Biological differences between Sarcocystis sp. from ibex and the other sarcosporidians with a canine-caprine or canine-ovine cycle are stressed.