Monitoring and management of wildlife health are of increasing importance in the last decades, first of all considering that more of 70% of emergent zoonoses are host in wild animals. Moreover the public health issue must be seen also in accordance with the European food hygiene regulations (Reg. EC 852, 853, 854/2004), that make hunters primary producers intended to auto-consumption and/or commercialization. We have to consider wildlife health value also in relation to possible interactions with livestock and to population dynamics and biodiversity preservation. We focused our attention on protozoa, parasites with the highest success spreading, in particular on Giardia, Cryptosporidium and Eimeria in chamois (Rupicapra rupicapra rupicapra and Rupicapra pyrenaica ornata), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Faecal samples were collected, in the biennium 2013-2014, from Lepontine Alps and from central Apennine. Through immunofluorescence emerged Giardia prevalence of 5,82% in R. r. rupicapra, and of 1,85% in R. p. ornata. Positive samples were confirmed by q PCR and end-point PCR, with identification of zoonotic assemblage A and livestock assemblage E. A parallel survey was conducted through immunoenzimatic methodology. Giardia showed prevalences of 4,5%, 2,5% and 8,4% while Cryptosporidium of 1,2%, 0,5% and 3,4% respectively in chamois, red deer and roe deer. Positive samples were subjected to molecular investigations. Assemblage A of Giardia was detected in chamois and red deer, suggesting a potential zoonotic risk, although rather low. Assemblage E was detected in chamois, highlighting a trasmission of this parasite between livestock and wildlife. Concerning Cryptosporidium, immunoenzimatic positivities haven’t been confirmed by PCR. Roe deer shows higher prevalences for both protozoa, statistical analyses about Giardia infection highlight a higher probability of calves being infected than adult, and higher significant probability to contract the infection in animals culled at lower altitudes, probably due to impact originated by human activities. Finally faeces were analysed by FLOTAC methodology in order to quantify emissions of coccidian oocysts and nematode eggs. Eimeria shows prevalence of 81,1% in chamois, 46,1% in red deer and of 43,4% in roe deer. Overall prevalences for gastro-intestinal nematodes are 76,4% in chamois, 57,4% in red deer and 67,1% in roe deer. Statistical analyses were carried out to define the epidemiological role of coccidian infections in wild ungulates in alpine context. Data collected about coccidia and gastro-intestinal nematodes don’t allow a correct definition of simultaneous parasitosis, considering nematodes possibility to infect several hosts. About that Eimeria represents a useful model to better understand interaction among pathogen, host and environment at intraspecific level, because of its strict host-specifity At the moment comparison between data about all protozoa investigated and alpine data census don’t suggest any impact on population dynamics. However it can not be completely excluded because of limits related to period of sampling that not always correspond to critical period for these infections in wild ungulates. We need to increase sampling season, compatibly with weather conditions, and to produce a data series about emissions of oocysts to better understand the eco-epidemiological role of protozoa in wildlife.

GIARDIA, CRYPTOSPORIDIUM AND EIMERIA INFECTIONS IN ALPINE WILD UNGULATES: EPIDEMIOLOGICAL INVESTIGATION AND MANAGEMENT IMPLICATIONS

TROGU, TIZIANA
2016

Abstract

Monitoring and management of wildlife health are of increasing importance in the last decades, first of all considering that more of 70% of emergent zoonoses are host in wild animals. Moreover the public health issue must be seen also in accordance with the European food hygiene regulations (Reg. EC 852, 853, 854/2004), that make hunters primary producers intended to auto-consumption and/or commercialization. We have to consider wildlife health value also in relation to possible interactions with livestock and to population dynamics and biodiversity preservation. We focused our attention on protozoa, parasites with the highest success spreading, in particular on Giardia, Cryptosporidium and Eimeria in chamois (Rupicapra rupicapra rupicapra and Rupicapra pyrenaica ornata), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Faecal samples were collected, in the biennium 2013-2014, from Lepontine Alps and from central Apennine. Through immunofluorescence emerged Giardia prevalence of 5,82% in R. r. rupicapra, and of 1,85% in R. p. ornata. Positive samples were confirmed by q PCR and end-point PCR, with identification of zoonotic assemblage A and livestock assemblage E. A parallel survey was conducted through immunoenzimatic methodology. Giardia showed prevalences of 4,5%, 2,5% and 8,4% while Cryptosporidium of 1,2%, 0,5% and 3,4% respectively in chamois, red deer and roe deer. Positive samples were subjected to molecular investigations. Assemblage A of Giardia was detected in chamois and red deer, suggesting a potential zoonotic risk, although rather low. Assemblage E was detected in chamois, highlighting a trasmission of this parasite between livestock and wildlife. Concerning Cryptosporidium, immunoenzimatic positivities haven’t been confirmed by PCR. Roe deer shows higher prevalences for both protozoa, statistical analyses about Giardia infection highlight a higher probability of calves being infected than adult, and higher significant probability to contract the infection in animals culled at lower altitudes, probably due to impact originated by human activities. Finally faeces were analysed by FLOTAC methodology in order to quantify emissions of coccidian oocysts and nematode eggs. Eimeria shows prevalence of 81,1% in chamois, 46,1% in red deer and of 43,4% in roe deer. Overall prevalences for gastro-intestinal nematodes are 76,4% in chamois, 57,4% in red deer and 67,1% in roe deer. Statistical analyses were carried out to define the epidemiological role of coccidian infections in wild ungulates in alpine context. Data collected about coccidia and gastro-intestinal nematodes don’t allow a correct definition of simultaneous parasitosis, considering nematodes possibility to infect several hosts. About that Eimeria represents a useful model to better understand interaction among pathogen, host and environment at intraspecific level, because of its strict host-specifity At the moment comparison between data about all protozoa investigated and alpine data census don’t suggest any impact on population dynamics. However it can not be completely excluded because of limits related to period of sampling that not always correspond to critical period for these infections in wild ungulates. We need to increase sampling season, compatibly with weather conditions, and to produce a data series about emissions of oocysts to better understand the eco-epidemiological role of protozoa in wildlife.
19-gen-2016
Inglese
LANFRANCHI, PAOLO
SIRONI, GIUSEPPE
LANFRANCHI, PAOLO
Università degli Studi di Milano
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/20.500.14242/170062
Il codice NBN di questa tesi è URN:NBN:IT:UNIMI-170062