Improving Hunted Wild Boar Carcass Hygiene: Roles of Different Factors Involved in the Harvest Phase

Abstract

Game meat production strongly differs from that of other meats, as peculiar factors present in the field and in the steps prior to transfer to a game-handling establishment can influence the hygiene of the carcasses and, therefore, of the meat. The effects of such factors were considered in hunted wild boars based on the main hygienic criteria adopted in meat processing. Environmental, animal, and hunting conditions were studied during two selective hunting seasons in Central Italy. A total of 120 hunted wild boar carcasses were sampled after the skinning process and analyzed for aerobic colony count, Enterobacteriaceae count, and Salmonella spp. isolation. The calculated mean values for aerobic colony and Enterobacteriaceae counts were 3.66 and 2.05 CFU/cm2, respectively, in line with the limits set for the meat of other ungulates by EU legislation. Salmonella spp. showed a prevalence of 2.5% (IC 95%: 1.72–3.27%). Statistical analysis of the data performed with the AIC criterion showed that the main parameter to consider for improving the hygienic level of carcasses is to reduce the time in the refrigerator before skinning, followed by hunting on cold days (<10 °C) without rain, hunting animals <60 kg, and reducing the time between shooting and evisceration.

Effect of time and temperature before chilling on the hygiene of carcasses in wild boar hunted in central Italy

“…Performing wild boar evisceration after three hours after shooting is nonetheless considered to be critical (Winkelmayer et al ., 2008 ). In the reported context of central Italy, even when evisceration is conducted on-field, a prompt refrigeration of the animal is recommended and could be achieved through the presence of available collection centers near the hunting areas (Ranucci et al , 2021 ), as the degree of microbial load increasing is correlate to the time between evisceration and refrigeration. When environmental temperature is near or over 20°C, even if a proportion between the temperature drop and time between the two step was registered, the body temperature drop before chilling is inadequate, and the carcasses remain at a temperature that allow bacteria to growth (27°C).…”

“…Other authors report that evisceration and skinning have to be performed within 6 hours from the shot (Decastelli et al , 1995 ). Nonetheless, when the environmental temperature is particularly high, from early spring to late autumn in central Italy, a quick and hygienically accurate evisceration of the hunted wild boars on-field or in a collection center (within two hours from the shot, Ranucci et al , 2021 ) combined with a suitable refrigeration (Borilova et al , 2016 ) to be performed within 6 hours from the evisceration, is strongly encouraged.…”

“…The survey was conducted on thirty wild boars hunted in Bologna and Perugia Provinces, central Italy. The animals were all hunted for selection with a “still hunting” method (Ranucci et al , 2021 ) properly shot to kill and eviscerated on field. After evisceration (average 1 hour and 18 minutes after the shot), the environmental temperature as well as the temperature of the carcass at the level of the Gracilis muscle were measured (FM12 Digital thermometer, Digitron, Frosinone, Italy) (T1), and a double swab samples (wet and dry swab, ISO 17604:2014) were collected from two inner surfaces on the right part of the carcass (superficial to the Psoas major muscle and superficial to the ribs at the level of the 9 th thoracic vertebra).…”

“…The main differences between the two chains involve steps that are under hunters’ control, such as the choice of the animal and the definition of its health status, the choice of the hunting day, the choice of the ammunition and hunting methods, the position of the shot, the bleeding and evisceration on field, the time and temperature before the arrival to a game handling establishment (Avagnina et al , 2012 ; Gomes- Neves et al , 2021; Mirceta et al , 2017 ). The hunter is therefore responsible of the carcass hygiene in the harvest phase (Branciari et al ., 2020 ; Orsoni et al ., 2020 ; Ranucci et al , 2021 ). A collection center for game meat nearby the hunting area, where carcass could be promptly eviscerated and refrigerated before sending to the game handling establishment, is not always available.…”

“…For this reason, the carcasses are usually eviscerated on field and sent before refrigeration to the collection center for chilling or directly to the game handling establishment, for skinning and chilling. The time necessary for non skinned carcasses to be sent to the game handling establishment, and the relative environmental carcass temperature, could affects microbial loads (Paulsen and Winkelmayer, 2004 , Vieira-Pinto et al , 2014 ; Ranucci et al , 2021 ). The EU legislation set that large wild game meat must be placed to the market only if the body is transferred to the game handling establishment “as soon as possible”, and refrigeration must begin “after a reasonable period of time” after killing (EC Regulation 853/2004).…”