Concentrations of strontium, barium, cadmium, copper, zinc, manganese, chromium, antimony, selenium and lead in the equine liver and kidneys

Ionomic Variation Among Tissues in Fallow Deer (Dama dama) by Sex and Age

(1) In mammals, the mineral nutrient and trace elemental composition of the body - the ionome - differs among individuals. It has been hypothesized that these differences may be related to age and sex, both for ecotoxic and essential elements. (2) We investigated whether and how intraspecific ionomic variation is related to age and sex in Fallow deer (Dama dama). We tested the predictions that concentrations of ecotoxic elements increase with age, that ionomic variation is lower among young individuals than among older individuals, and that reproductive females (does) have the lowest concentrations of essential elements. (3) Culled animals of different sex and age were obtained from a single protected area. The animals were dissected to collect 13 tissues, and concentrations of 22 different elements were measured in a sample of each tissue. (4) We described substantial ionomic variation between individuals. Some of this variation was related to age and sex, as predicted. Based on the limited existing knowledge on chemical element allocation and metabolism in the body, sex-related differences were more difficult to interpret than age-related differences. Since reference values are absent, we could not judge about the consequences of the elemental values that we found. (5) More extensive ionomic surveys, based on a wide range of elements and tissues, are needed to enlarge the understanding of within-species ionomic variation and potential biological, ecological, and metabolic consequences.

Reference intervals for trace mineral and heavy metal concentrations in horse livers in the Netherlands

We determined reference intervals (RIs) for concentrations of trace minerals and toxic elements based on liver samples from 122 apparently healthy horses at 2 slaughter facilities in the Netherlands. Samples were collected during the spring and fall of 2021, and the sex and age of the horses were registered upon sampling. Concentrations of arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc were measured in liver samples using inductively coupled plasma-mass spectrometry (ICP-MS) after nitric acid digestion. RIs were calculated using Reference Value Advisor software. The concentrations of most elements were not significantly different between sexes or in different seasons. Cadmium concentrations were higher than the European maximum residue limit of 2 mg/kg DW in 89% of livers. Positive significant correlations were observed between some elements (iron, molybdenum, lead, vanadium), and significant negative correlations between others (manganese, iron).

Heavy Metal(loid) Accumulation in the Ovarian Tissue of Free-Ranging Queens and Bitches Inhabiting Highly Polluted Urban Environments

There is strong scientific evidence that exposure to environmental contaminants, such as heavy metal(loid)s (HMs), can impair female reproductive function. Pets, such as cats and dogs, who share the same habitat as humans, may be particularly useful sentinel models for detecting HMs in the ovary. In the present study, we compared the concentration of essential (Ems; Cu, Fe, Mn, Se, and Zn) and non-essential metal(loid)s (NEMs; Al, As, Cd, and Pb) in the ovarian tissues of free-ranging queens and bitches of different ages living in industrialized/highly polluted (south group) and non-polluted (north group) urban areas of the island of Sardinia, Italy. The results showed that both EMs and NEMs were present at detectable concentrations in feline and canine ovaries and their levels varied according to geographical areas and animal age. Among the EMs, Cu was found elevated in older queens and bitches inhabiting the southern area. Cadmium and lead were higher in feline and canine ovaries of older animals from the south compared to those living in the north. In addition, Cd and Pb concentrations increased in individuals of both species living in the south. These findings showed new perspectives for the use of pets as early warning sentinels of environmental pollution by HMs and for the risk of human exposure within a "One Health" approach. Pets may help to study the link between exposure to metals and female reproductive disturbances in mammals.

[Effects of oral manganese supplementation with different compounds on the manganese whole blood and serum concentrations of broodmares and their suckling foals]

OBJECTIVE

This study aimed to examine the effects of an oral supplementation on manganese (Mn) concentrations in the blood of lactating warm-blood broodmares. Furthermore, the potential relationship between Mn supply of the lactating mare and its suckling foal was investigated.

MATERIAL AND METHODS

During the 90-day trial, lactating mares were divided into 3 groups and daily received a daily dose of either a placebo (n = 11) or a Mn supplement of 560 mg Mn as Mn sulfate (n = 11) or Mn chelate (n = 11) in addition to the Mn intake from the basal ration (hay ad libitum, total mixed ration: Mn intake ~ 100 mg/kg dry matter). Blood samples were taken from the mares and their foals in 14-day intervals. The Mn determination in serum and whole blood as well as in the mare's milk was carried out by means of mass spectrometry with inductively coupled plasma. The Mn analysis in representative feed samples was performed by means of atomic absorption spectrometry. Data were assessed using the software IBM SPSS Statistics 27 (IBM Deutschland GmbH, Ehningen).

RESULTS

During the trial period, the mares showed Mn concentrations 10-fold higher in whole blood (median: 15.6 µg/l; 25-75 percentile: 12.8-18.5 µg/l) than in serum (median: 1.54 µg/l; 25-75 percentile: 1.20-1.90 µg/l). The foals had Mn whole-blood concentrations 16.4-fold higher (median: 21.3 µg/l; 25-75 percentile: 16.7-28.1 µg/l) compared to their serum (median: 1.50 µg/l; 25-75 percentile: 1.30-1.70 µg/l). The Mn whole-blood levels of the foals corresponded to 1.6-fold the Mn concentration of their dams. The milk contained a median Mn concentration of 0.012 mg/kg fresh matter. Mn supplementation had no effect on the Mn blood levels of mares and their foals.

CONCLUSION AND CLINICAL RELEVANCE

Blood Mn concentrations were not affected by the Mn supplementation. However, the Mn levels differed significantly between serum and whole blood. In addition, the Mn concentrations in whole blood of suckling foals were higher compared to their dams, although the Mn concentrations in the mare's milk were low regardless of Mn supplementation. Due to the low Mn content in milk, early Mn supply, preferably by forages, is necessary to ensure that the foals are supplied with Mn according to their requirement.

Impact of Dietary Zinc Chloride Hydroxide and Zinc Methionine on the Faecal Microbiota of Healthy Adult Horses and Ponies

Zinc supplements are often used in equine nutrition to support skin and hoof quality or the immune function. However, no data on the effects of dietary zinc on the intestinal microbiota of horses and ponies are available so far. In the present study, varying dietary zinc concentrations (maintenance (4 mg/kg BW^0.75/day), 120 mg/kg dry matter (DM)/day and 240 mg/kg DM/day) were achieved by the supplementation of either zinc chloride hydroxide or zinc methionine (six treatment periods of 4 weeks each). Eight healthy adult ponies and two healthy adult horses were included, and faecal samples were collected at the end of each treatment period to analyse the microbiota (16S rDNA sequencing) and microbial metabolites. With increasing dietary zinc concentrations, the richness of the faecal microbiota decreased, independently of the zinc compound used. In addition, a decrease of the relative abundance of Bacteroidetes and Fibrobacteres as well as of acetate and total short-chain fatty acids in the faeces of the animals was observed at high zinc intakes. Effects on the bacterial order, family and genus level were also detected, which were partly more pronounced for zinc chloride hydroxide. It can be concluded that high dietary zinc levels decrease the richness and fermentative activity of the faecal microbiota of horses and ponies. Although all animals were healthy throughout the study, the effects could be critical for gut health, and deserve more research. The detected differences between the zinc compounds used indicate differences in the bioavailability of organic and inorganic zinc sources in equines.

[Manganese concentrations in whole blood, plasma and serum of adult warmblood horses from 3 locations in Germany]

OBJECTIVE

This study aimed to establish reference intervals for Mn in whole blood, plasma and serum of healthy, adult warmblood horses with known dietary Mn intake and to compare 2 methods of analysis.

MATERIAL AND METHODS

Between May 2018 and November 2019 a single blood sample was taken from a total of 270 clinically healthy horses (age: 3-25 years) in 3 stud farms. In lithium-heparin (LH) whole blood, LH plasma and serum Mn concentrations were analyzed by means of atomic absorption spectrometry (AAS) and inductively coupled plasma mass spectrometry (ICP-MS). The reference intervals were calculated according to the recommendations of the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) and the Clinical and Laboratory Standards Institute (CLSI) comprising the range between 2.5 and 97.5 percentile of the analyzed Mn concentrations. Concurrent to blood sampling feed samples were taken and analyzed in order to determine the Mn content of the corresponding feeding ration.

RESULTS

The horses' whole-blood Mn levels were significantly (p < 0.0001) higher with a median Mn concentration of 12.4 μg/l (reference interval: 4.99-25.1 μg/l [AAS]; 5.99-25.3 μg/l [ICP-MS]) than in the corresponding serum (median: 1.65 μg/l, reference interval: 0.60-3.50 μg/l [AAS]; 1.11-2.96 μg/l [ICP-MS]) or LH plasma (median: 1.35 μg/l, reference interval: 0.22-2.68 μg/l [AAS]; 0.59-2.45 μg/l [ICP-MS]). In the comparison of methods, there were statistically significant differences in the Mn determinations for LH plasma and serum between AAS and ICP-MS, whereas they yielded comparable results for whole blood.

CONCLUSION AND CLINICAL RELEVANCE

Whole blood shows an average of 10-fold higher Mn concentrations than serum or LH plasma. When evaluating blood Mn concentrations, consideration must be granted to the sample material under analysis as well as to which method is employed since relevant differences were found between AAS and ICP-MS in serum and LH plasma.

Lowland tapir exposure to pesticides and metals in the Brazilian Cerrado

Abstract ContextThe Cerrado is a Global Biodiversity Hotspot as well as Brazil’s main frontier for large-scale agriculture and livestock production, making it one of the most threatened biomes in the country. Brazil is one of the biggest consumers of pesticides in the world and allows the use of chemicals that are banned in many other countries due to their adverse health effects in a wide range of species, including humans. AimsThis study aimed to assess pesticide and metal exposure of the lowland tapir – a threatened, large herbivorous mammal – to support future studies of the role of these chemicals in tapir health, survivorship, and population viability. MethodsFoot pad, proboscis, stomach contents, liver, bone, and nail samples were obtained from tapir carcasses found along highways (n=87). (i) Atomic absorption spectrophotometry (AAS) was used to detect metals in bone, nail and liver tissue; (ii) gas chromatography – nitrogen phosphorous detector (GC-NPD) to detect organophosphates in liver and skin; and (iii) high performance liquid chromatography – ultraviolet (HPLC-UV) to detect pyrethroids and carbamates in stomach contents. Key resultsTwo carbamates (aldicarb and carbaryl), three organophosphates (diazinon, malathion, and mevinphos), two pyrethroids (deltamethrin and permethrin), and two toxic metals (cadmium and lead) were detected in different tapir tissue samples, some at concentrations high enough to cause adverse health effects. In 90% of roadkill tapirs that were subjected to a full post-mortem examination (n=25), macroscopic alterations of liver and/or kidney tissue were observed. ConclusionsThis study provides the first report to date of the detection of pesticides and metals in lowland tapirs. ImplicationsSome of the reported pesticide concentrations exceed environmental safety thresholds. Consequently, results from this study raise concerns over potential adverse health effects in tapirs that could lead to population level impacts, thus requiring further investigation.

The impact of polar fraction of the fine particulate matter on redox responses in different rat tissues

Particulate matter (PM) contains different chemical substances that have been associated with health effects and an increased risk of mortality due to their toxicity. In this study, fine particulate matter (PM_2.5) samples were collected in a region with rural characteristics (Seropédica (Se)) and another with some industries (Duque de Caxias (DC)) (Brazil, RJ). Rats were exposed to PM_2.5 extracts daily for 25 days at different dilutions: 10×, 5×, and a concentrated solution (CS). Biochemical analyses were investigated for total antioxidant capacity (ACAP), lipid peroxidation (LPO) levels, reduced glutathione (GSH) concentration, activity of glutamate cysteine ligase (GCL), and activity of glutathione S-transferase (GST). The liver showed a significant increase in GCL (DC-5×, DC-CS and Se-CS) and GST activities (DC-CS and Se-CS) in both regions when compared to the control group. In the renal cortex, GCL activity decreased in most of the tested groups while GST activity increased only in the 5× groups of both regions (DC and Se). In the renal medulla, GCL activity decreased for Se-10× and DC-CS but increased for Se-5×, and GST activity increased in the Se-10×, DC-5×, and DC-CS groups. Lung GCL increased in all groups for both regions. Moreover, this organ also showed an increase in GST activity when higher metal concentrations were present (5× and CS). TBARS levels were increased for all tissues in most tested concentrations. These data indicate that soluble compounds (e.g., metals) from PM_2.5 sampled in areas with different pollution indexes can change the redox status and cause damage to different tissues.

Presence of cadmium residues in muscle, liver and kidney of Bubalus bubalis and histological evidence

Cadmium (Cd) concentrations were evaluated in the samples of kidney, liver and muscle of sixty-six buffaloes regularly slaughtered. Forty were raised in Campania, in the territory between the province of Naples and Caserta and twenty-six were bred in Apulia, in the province of Bari. Two aliquots were prepared for the renal and hepatic samples: one intended for the chemical analysis and the other one intended for histological investigations. Muscle samples were the subject of purely chemical investigation. In the group of forty animals raised in the Campania region, the limits imposed by EC Reg. 1881/2006 and EC Reg. 488/2014 were exceeded in three renal samples, which showed values of 1.53, 1.22 and 1.1 mg/kg respectively; in three hepatic samples, which presented values of 0.72, 0.64 and 0.61 mg/kg, and in five muscle samples, with values of 0.16, 0.16, 0.09, 0.08 and 0.07, respectively. On the other hand, in the group of animals raised and slaughtered in the province of Bari, none of the twenty-six samples examined exceeded the limits imposed by the European regulations. The histological analysis showed typical, but not pathognomonic lesions in the renal samples from the animals raised in the provinces of Naples and Caserta. The levels of Cd contamination found in the samples examined suggest that it would be correct to exclude from the human consumption, as it happens for the equines, the kidney and the liver, especially from the animals raised in some geographical areas with a high rate of pollution.

Investigating aquifer contamination and groundwater quality in eastern Terai region of Nepal

OBJECTIVE

This study aims at assessing the groundwater quality of the three districts of Eastern Terai region of Nepal viz. Morang, Jhapa, Sunsari using physicochemical characteristics and statistical approach so that possible contamination of water reservoir can be understood. pH, temperature, conductivity, turbidity, color, total dissolved solids, fluorides, ammonia, nitrates, chloride, total hardness, calcium hardness, calcium, magnesium, total alkalinity, iron, manganese, arsenic have to be analyzed to know the present status of groundwater quality.

RESULTS

Results revealed that the value of analyzed parameters were within the acceptable limits for drinking water recommended by World Health Organization except for pH, turbidity, ammonia and iron. As per Nepal Drinking Water Quality Standards, fluoride and manganese too were not complying with the permissible limit. Electrical conductivity, total dissolved solids, chloride, total hardness, calcium hardness, manganese, and total alkalinity show good positive correlation with major water quality parameters. Calcium, magnesium, total hardness, calcium hardness and total alkalinity greatly influences total dissolved solids and electrical conductivity. ANOVA, Tukey, and clustering highlight the significance of three districts. Groundwater can be considered safe, but there is always a chance of contamination through chemical wastes in the heavily industrialized area of Morang and Sunsari Industrial corridor.