Content of Selected Macro- and Microelements in the Liver of Free-Living Wild Boars (Sus Scrofa L.) from Agricultural Areas and Health Risks Associated with Consumption of Liver

Concentration of selected biogenic and risk elements in liver, kidneys and muscle of domestic rabbit and wild brown hare

In the present study the concentration of selected elements in tissues of domestic rabbits and of wild brown-hares (kidneys, liver, and muscle - m. quadriceps femoris) in Slovakian habitats were determined. After mineralization the elements examined were detected using flame atomic absorption spectrophotometry/graphite furnace atomic absorption spectrophotometry. For rabbits, Fe in the liver was correlated with essential (Mn, Cu) (R2 = 0.94, p < 0.05; R2 = 0.96, p < 0.05 respectively) or toxic (Pb) elements (R2 = -0.93, p < 0.05). For hares, significant correlations were found between Cd and Cu or between Cd and Mn in the kidneys (R2 = -0.96, p < 0.05; R2 = 0.92, p < 0.05 respectively), which is the target organ for Cd. Higher concentrations of the elements were found in hare tissue, and this may be linked to pollution of their wild habitats. The xenobiotic elements as well as the essential elements were accumulated in the kidneys of the hares than rabbits. For liver, differences were less pronounced and significance was only for Fe and Cu. Muscle of hares was more contaminated than of rabbits for both biogenic and toxic elements. These results show that detectable concentrations of inorganic elements. These levels may be linked to contamination of the natural habitats of wild biota due to industry, traffic, agriculture, and urban sprawl.

Salmonella in Wild Boar Meat: Prevalence and Risk Assessment in Central Italy (Umbria and Marche Region)

A survey was conducted from 2018 to 2023 to assess the presence of Salmonella in 280 hunted wild boar (carcasses after evisceration and skinning, N = 226; liver, N = 258; and fecal samples, N = 174). The overall prevalence was 2.86% (confidence interval 95%, 1.45-5.45%) with five positive samples detected in carcasses, three in the liver, and one in a fecal sample. This prevalence was in line with those found in nearby areas denoting a low number of positive samples. Positive animals were over 24 months of age and weighed, before skinning, 59.00 ± 9.11 Kg and no difference was detected in microbial loads between samples positive and negative for Salmonella (aerobic colony count of 4.59 and 4.66 log CFU/400 cm2, and Enterobacteriaceae count of 2.89 and 2.73 log CFU/400 cm2 (mean values) in positive and negative subjects, respectively). Salmonella Stanleyville was the most frequently isolated serotype. A semiquantitative risk assessment was conducted for the first time in game meat considering two products, meat cuts intended for cooking and fermented dry sausages. Only proper cooking can reduce the risk of ingestion of Salmonella to the minimum for consumers, whereas ready-to-eat dry sausages constitute risk products in terms of foodborne Salmonellosis (risk score of 64 out of 100).

Monitoring of metal content in the tissues of wild boar (Sus scrofa) and its food safety aspect

The study was performed on 10 female and 10 male wild boars (Sus scrofa) after shooting during the regular hunting season to investigate the concentration of metals in the muscle and fat tissue. The concentrations of essential and non-essential elements were determined (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), lead (Pb), manganese (Mn), mercury (Hg), and zinc (Zn)) using inductively coupled plasma optical emission spectrometry. The concentrations of As, Hg, and Cd were below the limit of detection (As, Hg: < 0.5 mg/kg, Cd: < 0.05 mg/kg) in every tissue sample of both sexes. The lead was detected as 0.36 ± 0.16 mg/kg and 0.22 ± 0.06 mg/kg in the muscle of females and males, respectively, showing a significant difference between the sexes (p = 0.0184). The measured concentration of Cr was 0.14 ± 0.08 mg/kg and 0.13 ± 0.06 mg/kg, and that of copper was 1.22 ± 0.14 mg/kg and 1.06 ± 0.16 mg/kg in the muscle of females and males, respectively. The same tendency was observed in the case of copper content of fat tissues (female: 0.13 ± 0.10 mg/kg; male: 0.13 ± 0.04 mg/kg; p = 0.2707). Manganese concentration of muscle was 0.45 ± 0.30 mg/kg (female) and 1.36 ± 0.96 mg/kg (male), and that of fat tissue was 0.32 ± 0.22 mg/kg (female) and 0.74 ± 0.75 mg/kg (male). The Zn was detected as 56.75 ± 7.86 mg/kg and 1.83 ± 0.76 mg/kg in the muscle and fat of females and 52.12 ± 11.51 mg/kg and 1.94 ± 0.57 mg/kg in males, respectively. Based on data, the consumption of fat and muscle tissues of the wild boars tested can be food toxicologically objectionable, mainly due to the lead content, and thus pose a risk to frequent consumers of this type of game meat.

Comparison of Lipid Properties and Cadmium and Lead Content in Red Deer (Cervus elaphus) Meat from Three Feeding Grounds

Simple Summary

As a product originating from the most natural living conditions with free foraging, red deer (Cervus elaphus) meat is becoming increasingly popular among consumers. A greater supply of this type of meat can be ensured by dynamically developing red deer farming on permanent grasslands. The study presents a comparison of the properties of lipids and the content of cadmium and lead in the LL and SM muscles of red deer kept in forest, organic farm, and conventional farm feeding grounds. The greater species and phytoncide diversity in the organic feeding ground enriched the quantitative profile and significantly increased the content of beneficial polyunsaturated fatty acids (FAs) (CLA—conjugated linoleic acid, ALA—alpha-linolenic acid, AA—arachidonic acid, and EPA—eicosapentaenoic acid) and the sum of polyunsaturated fatty acids (PUFAs), n-6 PUFA, and n-3 PUFA, in comparison with conventional farm and forest feeding grounds. It also contributed to a significantly lower n-6/n-3 ratio in both muscles. The study provides valuable data on the nutritional value and ecological safety of venison, which should be regarded as a health-enhancing food product. Furthermore, the present results can help breeders to make decisions about the locations of farms and the choice of red deer nutrition strategies.

Abstract

The aim of the study was to compare the properties of lipids and the content of cadmium and lead in the meat of red deer (Cervus elaphus) kept in a forest feeding ground (FFG) and on organic and conventional farms in Poland. Longissimus lumborum (LL) and Musculus semimembranosus (SM) muscles were collected for the study from 36 red deer carcasses in an equal sex and age ratio (3 and 4 years old). From April to October, the animals consumed only the vegetation growing in the feeding grounds. The floristic and phytoncide composition, as well as the fodder value, of the feeding grounds were assessed. Additionally, the intramuscular fat and cholesterol content, the profile, sum, and ratios of fatty acids (FAs), lipid nutraceutical parameters, and cadmium and lead content were determined in LL and SM. The plant composition comprised 116 species in the organic feeding ground (OFG) and 78 species in the conventional feeding ground (CFG). The LL and SM muscles of the red deer from the organic and forest feeding grounds exhibited significantly lower amounts of fat and cholesterol than those from the conventional system. The differences in the fatty acid composition between the three groups were quite small. Differences in intramuscular fat content contributed to a higher percentage of PUFAs in the FFG and OFG, in comparison to the CFG. In all types of feeding ground, the cadmium (0.002 to 0.008 mg/kg) and lead (0.009 to 0.019 mg/kg) content determined in the meat did not pose a threat to consumers.

Development of an Immunoassay for the Detection of Copper Residues in Pork Tissues

The presence of high concentrations of copper (Cu) residues in pork is highly concerning and therefore, this study was designed to develop a high-throughput immunoassay for the detection of such residues in edible pork tissues. The Cu content in the pork samples after digestion with HNO₃ and H₂O₂ was measured using a monoclonal antibody (mAb) against a Cu (II)–ethylenediaminetetraacetic acid (EDTA) complex. The resulting solution was neutralized using NaOH at pH 7 and the free metal ions in the solution were chelated with EDTA for the immunoassay detection. An indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) method was developed for Cu ion analysis. The half maximal inhibitory concentration of the mAb against Cu (II)–EDTA was 5.36 ng/mL, the linear detection range varied between 1.30 and 27.0 ng/mL, the limit of detection (LOD) was 0.43 μg/kg, and the limit of quantification (LOQ) was 1.42 μg/kg. The performances of the immunoassay were evaluated using fortified pig serum, liver, and pork samples and had a recovery rate of 94.53–102.24%. Importantly, the proposed immunoassay was compared with inductively coupled plasma mass spectroscopy (ICP-MS) to measure its performance. The detection correlation coefficients of the three types of samples (serum, pork, and liver) were 0.967, 0.976, and 0.983, respectively. Thirty pork samples and six pig liver samples were collected from local markets and Cu was detected with the proposed ic-ELISA. The Cu content was found to be 37.31~85.36 μg/kg in pork samples and 1.04–1.9 mg/kg in liver samples. Furthermore, we detected the Cu content in pigs with feed supplemented with tribasic copper chloride (TBCC) and copper sulfate (CS) (60, 110, and 210 mg/kg in feed). There was no significant difference in Cu accumulation in pork tissues between the TBCC and CS groups, while a remarkable Cu accumulation was found for the CS group in liver at 210 mg/kg, representing more than a two-fold higher level than seen in the TBCC group. Therefore, the proposed immunoassay was found to be robust and sensitive for the detection of Cu, providing a cost effective and practical tool for its detection in food and other complicated samples.

The Levels of Mineral Elements and Toxic Metals in the Longissimus lumborum Muscle, Hair and Selected Organs of Red Deer (Cervus elaphus L.) in Poland

Simple Summary

The relationships between nutritive elements (Fe, Mn, Zn, Cu, Na, K, Ca and Mg) and toxic metals (Pb and Cd) can inform the assessment of health status of red deer, which are exposed to pollution in their natural environment. These elements in the longissimus lumborum muscle, hair and selected organs of red deer (Cervus elaphus L.) were analysed. The study revealed many significant correlations between the levels of elements and their high variability in individual tissues and organs. The accumulation of a specific metal in a tissue or organ can reduce its concentration in another matrix or promote increased content in another tissue or organ.

Abstract

The aim of the study was to analyse correlations and variability between the levels of mineral elements (Fe, Mn, Zn, Cu, Na, K, Ca and Mg) and toxic metals (Pb and Cd) in the longissimus lumborum muscle, hair and selected organs of red deer (Cervus elaphus L.). The levels of mineral elements were measured using atomic absorption spectroscopy (F-AAS). The levels of Pb and Cd were analysed by means of electrothermal atomic absorption spectroscopy (ET-AAS). Of all analysed microelements, the highest concentration (in g·kg⁻¹ of dry weight) was found for Fe in the liver. Considering all macroelements, the highest level was found for K in the longissimus lumborum muscle. Particularly remarkable was the high level of Pb in the muscle and hair of red deer. The level of Cd in the hair was four to five times lower than in other samples. The study revealed many significant correlations between the levels of certain elements in individual tissues and organs. There were significant correlations between Cu-Fe (r_xy = 0.650; p ≤ 0.01), Pb-Cu (r_xy = −0.863; p ≤ 0.01) and Cd-Ca (r_xy = −0.743; p ≤ 0.01) in testicles. For kidneys, a significant negative correlation was found for K and Na (r_xy = −0.779; p ≤ 0.01) and for Ca and Cd (r_xy = −0.695; p ≤ 0.01), and a positive correlation between Cu and Mn (r_xy = 0.693; p ≤ 0.01). In the liver, significant negative correlations were found between Ca-K (r_xy = −0.654; p ≤ 0.05), Cd-Fe (r_xy = −0.651; p ≤ 0.05) and Pb-Cu (r_xy = −0.627; p ≤ 0.05). In the muscle, only single significant correlations were found between Cd and Mn (r_xy = 0.648; p ≤ 0.05). The highest number of significant correlations were recorded for the hair, among others between Na-K (r_xy = 0.760) and Ca-Zn (r_xy = 0.709) at p ≤ 0.01. The study revealed high variability in the levels of mineral elements and selected toxic metals in tissues, organs and hair of red deer. Additionally, this research confirmed that the accumulation of a specific metal in a tissue or organ can reduce its concentration in another matrix or promote its increased content in another tissue or organ.