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’ 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’ 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.
WILD GAME MEAT: HEALTH MONITORING TO PROTECT CONSUMERS / N. Formenti ; tutor: P. Lanfranchi ; coordinatore: G. Sironi. DIPARTIMENTO DI SCIENZE VETERINARIE E SANITA' PUBBLICA, 2014 Feb 11. 26. ciclo, Anno Accademico 2013. [10.13130/formenti-nicoletta_phd2014-02-11].
WILD GAME MEAT: HEALTH MONITORING TO PROTECT CONSUMERS
N. Formenti
2014
Abstract
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’ 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’ 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.File | Dimensione | Formato | |
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