1,061 research outputs found
WILD GAME MEAT: HEALTH MONITORING TO PROTECT CONSUMERS
Wildlife has gained an increasingly importance worldwide during last decades for its central role in transmission of different-value infections (zoonotic, zoo-economic, threatening biodiversity). Moreover considering the use of wild animals as food resource, the attention should be posed to the rise in consumption and commercialization of game meat. In this regard the new European food hygiene regulations (Reg. EC. 852, 853, 854/2004) authorized the auto consumption and the commercialization of these products, according to specific requirements, promoting their spread on a large scale. Nonetheless a scheduled health monitoring of free-ranging animals is still not defined.
Considering the significant increase of wild ungulate populations recorded in Italy during last decades and the consequent substantial amount of game meat available every year from hunting plans, health guaranteed for consumers\u2019 protection should be provided in relation to food-borne zoonoses and microbiological contaminations of carcasses. The starting point of this program should be the definition of a reliable diagnostic testing methods although is not always easy because usually diagnostic tests applied to wildlife were sharpened from domestics compromising their performances in most of the times.
Considering the highest human incidence of Toxoplasma gondii among parasitic zoonoses, the documented role of wild animals as its intermediate hosts and the few information about T. gondii impact on free-ranging ungulate population dynamics, we performed: (1) a sero-epidemiological and molecular investigations of Toxoplasma gondii in red deer (Cervus elaphus), roe deer (Capreolus capreolus), alpine chamois (Rupicapra r. rupicapra) to investigate (i) the spreading of the protozoan within host populations (ii) the reliability of cardiac tissue fluids as an alternative to sera in ELISA test (iii) the applicability of three PCR protocols; (2) the microbiological conditions of wild boar carcasses through superficial and deep tissue analysis.
T. gondii-type II DNA was detected in an alpine chamois (p = 2%, 1 subjects over 50 analyzed) for the first time, to our knowledge, by all the three performed PCRs pointing out a good sensitivity of protocols, genotyping test included. This result should be taken into consideration in case of consumption of raw or undercooked meat rather than in case of manipulation of carcasses.
A few diagnostic problems emerged in both serological and molecular investigation, mainly for cervids (n = 208): doubtful PCR products were recorded (n = 30) and in two red deer Sarcocystis spp. DNA was then detected. In addition, cardiac tissue fluids cannot be considered as an alternative of serum using this ELISA test in red deer (n = 78).
Considering T. gondii effect on red deer population dynamics, statistical analysis points out that the infection seems not to prevent red deer hinds (n = 34) to become pregnant although a negative effect of the pathogen on foetus development of 2-3 year-old hinds was recorded highlighting that under determinate conditions T. gondii could give an impact on the population dynamics with a delay in mating or in pregnancy.
Microbiological analysis (n = 27 for superficial and n = 17 for deep tissue analysis) showed still a few considerable hunters\u2019 deficiencies in the application of hygienic practices for the management of culled animals. Even if it is difficult that hunted carcasses maintained a similar bacterial levels of those of slaughtered ones, because of several logistic field problems, some increase of Total Aerobic Counts and Enterobacteriaceae recorded in this research could have been easily avoided through a better manipulation from culling to cooling.
Considering the few difficulties in diagnostic testing of T. gondii and the inadequate healthy practices of hunters, the need is to define preventive programmes to sensitize consumers and risk category (hunters, slaughters, etc.) to inform about toxoplasmosis and other health risks related to wildlife. In addition, a strict involvement of hunting associations in regular continuing education courses should be planned to create well-formed hunters who could be able to make the best use of the intrinsic valuable potentialities of wild game meat and at the same time commercializing healthy
and qualitative products
Toxoplasma gondii infection in alpine red deer (Cervus elaphus): Its spread and effects on fertility
In contrast to the depth of knowledge on the pathological effects of parasitism in domestic animals, the impact of the vast majority of parasites on wildlife hosts is poorly understood and, besides, information from domestics is rarely usable to disclose the parasites' impact on free-ranging populations' dynamics. Here we use Toxoplasmosis as a study model since, until now, the infection process and the protozoan's effects in natural conditions has received little attention. We analysed 81 sera from red deer (Cervus elaphus) sampled in Italian Alps and through generalized linear models we evaluated (1) the epidemiological factors influencing T. gondii infection dynamics; (2) its impact on female fertility [corrected]. High seroprevalence of T. gondii infection was recorded in yearling (1 year-old; prevalence = 52.4%) and adult (>2 year-old; prevalence = 51.3%) red deer, while calves (<1 year-old) did not contract the infection suggesting horizontal transmission as the main route of infection. The stable prevalence between yearlings and adults and the higher serological titres of younger individuals lead to two alternative infection processes suggesting a difference between age classes or in acquiring the infection or in responding to the pathogen. No associations between T. gondii serological titres and pregnancy status was observed indicating no direct effect on the probability of being pregnant; nevertheless a relation between females' higher serological titres and lower foetal development emerged, suggesting potential effects of the parasite infection on deer reproduction. The results demonstrate high seroprevalence of T. gondii infection in free-ranging red deer and, furthermore, the effect on foetal development suggests the potential impact of the parasite on red deer fertility and thus on its population dynamics
Conservation Laws in Cellular Automata
If X is a discrete abelian group and B a finite set, then a cellular
automaton (CA) is a continuous map F:B^X-->B^X that commutes with all X-shifts.
If g is a real-valued function on B, then, for any b in B^X, we define G(b) to
be the sum over all x in X of g(b_x) (if finite). We say g is `conserved' by F
if G is constant under the action of F. We characterize such `conservation
laws' in several ways, deriving both theoretical consequences and practical
tests, and provide a method for constructing all one-dimensional CA exhibiting
a given conservation law.Comment: 19 pages, LaTeX 2E with one (1) Encapsulated PostScript figure. To
appear in Nonlinearity. (v2) minor changes/corrections; new references added
to bibliograph
Atmospheric aerosols at the Pierre Auger Observatory and environmental implications
The Pierre Auger Observatory detects the highest energy cosmic rays.
Calorimetric measurements of extensive air showers induced by cosmic rays are
performed with a fluorescence detector. Thus, one of the main challenges is the
atmospheric monitoring, especially for aerosols in suspension in the
atmosphere. Several methods are described which have been developed to measure
the aerosol optical depth profile and aerosol phase function, using lasers and
other light sources as recorded by the fluorescence detector. The origin of
atmospheric aerosols traveling through the Auger site is also presented,
highlighting the effect of surrounding areas to atmospheric properties. In the
aim to extend the Pierre Auger Observatory to an atmospheric research platform,
a discussion about a collaborative project is presented.Comment: Regular Article, 16 pages, 12 figure
Increased hormonal stress response of Apennine chamois induced by interspecific interactions and anthropogenic disturbance
Responses of animals to environmental changes and their interactions with other species play an important role in conservation. Sharing a common habitat may lead to interspecific competition for resources, but field assessment of these biological events is not always easily accomplished. By using a non-invasive method, we evaluated the physiological stress responses of Apennine chamois (Rupicapra pyrenaica ornata) to the presence of cattle, sheep and goat, red deer (Cervus elaphus), people (hikers), and predators to identify which factors may affect this endangered species. During September 2012, November 2012, and July 2013, a total of 318 faecal samples were collected in representative sites and analysed for faecal cortisol metabolites (FCM). FCM concentration was analysed through linear mixed-effect models. A significant increase in FCM values in Apennine chamois sharing their habitat with domestic animals was recorded during all study periods. On the contrary, stress responses to red deer and people were limited in time and emerged only during summer months, when hikers are more frequent and red deer extend their altitudinal range reaching chamois\u2019 habitat. The observed effects of domestic animals, red deer, and hikers should be considered in future Apennine chamois management plans, which should include the regulation of pastured domestic livestock, anthropogenic disturbances, and possible interferences with other wild species within parks
Molecular identification of cryptic cysticercosis : Taenia ovis krabbei in wild intermediate and domestic definitive hosts
The complex life cycle of taeniids represents an ideal model of a multi-host system. The complexity of these parasites can therefore cover the epidemiological issues of the interface between wild and domestic animals, especially once spatial overlap between wild and domestic definitive and intermediate hosts occurs. Here we use the occurrence of Taenia ovis krabbei in two model areas as an example of this epidemiological complexity. In two contiguous areas in the Italian northern Apennines, two hunted roe deer (Capreolus capreolus) showed numerous cysticerci in the muscles of their whole body and an adult tapeworm was recorded in a semi-stray dog (Canis lupus familiaris). Through molecular typing of the mitochondrial cytochrome c oxidase I (cox1) gene, cysticerci and the adult tapeworm of T. krabbei were identified. Taenia krabbei cysticercosis was recorded for the first time in Italy. Although the role of dogs in the parasite's life cycle emerges, the overlap between wild and domestic definitive hosts and the increase of wild population densities raise concerns about the temporal (old or new) introduction and the spread of this parasite by one of these canid species (wolf (Canis lupus) or dog). Although T. krabbei is not a public health issue, economic concerns emerged for hunters and meat producers, related to the damage of carcasses by cysticerci. Therefore, there is a need to evaluate the spread of T. krabbei in the intermediate and definitive host populations, and to ensure the relevant sanitary education for hunters in order to avoid practices that could favour the spread and maintenance of its life cycle
Bilateral asymmetry of skin temperature is not related to bilateral asymmetry of crank torque during an incremental cycling exercise to exhaustion
© 2018 Trecroci et al. Although moderate relationships (|r|~0:5) were reported between skin temperature and performance-related variables (e.g., kinetic), it remains unclear whether skin temperature asymmetry reflects muscle force imbalance in cycling. Therefore, the aim of this study was to assess whether a relationship exists between kinetic and thermal asymmetry during a fatiguing exercise. Ten elite cyclists were enrolled and tested on a maximal incremental cycling test. Peak crank torques of both legs were obtained at the initial and final workload. Likewise, bilateral skin temperatures were recorded before and after exercise. Asymmetric indexes were also calculated for kinetic (AIK) and skin temperature (AIT) outcomes. The bilateral peak crank torques showed a larger difference at the final compared to the initial workload (p0:05). Additionally, trivial relationships were reported between AIK and AIT (-0:3<r<0:2) at the initial and final workload. The obtained results showed that changes in bilateral kinetic values did not reflect concurrent changes in bilateral skin temperatures. This finding emphasizes the difficulty of associating the asymmetry of skin temperature with those of muscle effort in elite cyclists. Lastly, our study also provided further insights on thermal skin responses during exhaustive cycling exercise in very highly-trained athletes
Helminth community of an alpine rock partridge (Alectoris græca) population in demographic crash
Alpine rock partridge (Alectoris gr\ue6ca) populations are drastically decreasing mainly due to habitat degradation and climate change. From 2003 to 2011, we investigate the helminth community of a rock partridge population from Lepontine Alps (Western Alps), showing a demographic crash in the last few years (2009-2010-2011), to analyse the helminth distribution within population in relation to different factors (sampling year, age, gender) and to disclose the parasites\u2019 role in this population trend.
From 213 intestinal contents of hunted rock partridges we recorded Ascaridia compar, Heterakis gallinarum and Aoncotheca caudinflata: the most abundant species is H. gallinarum with a significant greater abundance in adults. A significant increase of abundance of all the three helminths was recorded in 2010. Juveniles and females were infected by the three helminths while in males we recorded H. gallinarum and A. caudinflata with lower abundances and prevalence.
Data show a temporal association between the demographical population crash and the abundance peak of all the three helminths suggesting a possible health impact of parasites. Even if data did not show any effect of parasites on body weights, the known effects of these parasites on fecundity indicate the likely effect of parasites as a predisposing factor for the observed demographic crash and points out the importance of the health monitoring in wildlife
The cooler the better? Indirect effect of spring-summer temperature on fecundity in a capital breeder
Female reproductive performance is a central component of ungulate population dynamics, and it can be influenced by individual, social, and environmental factors. Researchers have often assumed direct effects of different predictors on reproduction, yet more complex relationships should be considered when investigating temporal variations in life\u2010history traits within a broader eco\u2010evolutionary context. In this study, we explored direct effects of individual, social, and environmental predictors on female reproductive performance and investigated potential causal chains among variables. We analyzed the variation in fecundity, measured as the probability of being pregnant, in 215 adult female deer Cervus elaphus culled on the Italian Alps, with respect to age, body mass, kidney fat, jaw length, lactation status, population size, temperature and precipitation in spring\u2013summer, temperature and snow depth in winter, and the delayed effect of spring\u2013summer temperature. We used random forest and logistic regression models to select variables whose direct effects best explained variation in fecundity. Path analysis was used to test for alternative hypotheses of direct/indirect effects between pre\u2010selected weather (spring\u2013summer temperature) and individual (age, kidney fat index [KFI]) predictors. The most important direct predictors of fecundity were age, kidney fat, and the interaction between kidney fat and spring\u2013summer temperature. Path analysis supported the hypothesis that higher spring\u2013summer temperature had negative, indirect effects on the probability of being pregnant, mediated by decreasing values of KFI. Our study revealed some complex, cause\u2013effect relationships between weather stochasticity, body condition, and reproduction, possibly suggesting a conditional trade\u2010off between opportunity for reproduction and survival, and emphasizing how environmental variations and individual characteristics may interact to shape life\u2010history traits in ungulate population
- …