The total content of toxic elements in horsehair given the level of essential elements

Mineral patterns in hair: A decisive factor between reproducible and repeat breeder dairy cows

Reproduction, especially impregnation, is a critical aspect of dairy cow management that directly influences herd milk productivity. We conducted a noninvasive hair mineral assay to compare the mineral profiles of two dairy cow groups: reproducible and repeat breeder, by investigating the levels of 11 essential minerals (Ca, Mg, Na, K, Fe, Cu, Mn, Zn, Cr, Se, and P) and 6 toxic elements (Hg, Pb, Cd, Al, As, and Ni) in both groups. We also conducted principal component and correlation matrix analyses to compare hair mineral patterns between the groups. Compared to their reproducible counterparts, repeat breeder cows had lower levels of Na, K, and Se. However, Fe, Cd, Al, and As levels were higher in repeat breeders than in their reproducible counterparts. The correlation matrix showed notable correlation patterns for each group. Ca, K, and Na levels were positively correlated in reproducible cows, whereas repeat breeder cows showed positive correlations only between Ca and K levels. Se showed positive correlations with Zn only in the reproducible cow group. Negative correlations were not found in the reproducible group, whereas the repeat breeder group exhibited 7 negative correlations. Despite the limitations of hair mineral analysis, this study provided useful insights into the reproductive potential of dairy cows. These findings aid in easing the prediction of repeat breeder occurrences in herds and are expected to facilitate timely mineral supplementation and other interventions to improve overall herd reproduction in dairy farms.

Equine odontoclastic tooth resorption and hypercementosis (EOTRH): microspatial distribution of trace elements in hypercementosis-affected and unaffected hard dental tissues

Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) is a common, painful and poorly understood disease. Enamel, dentin and cementum accumulate both essential and toxic trace elements during mineralization. Characterization of the spatial accumulation pattern of trace elements may provide insight into the role that toxic elements play and inform biological processes affecting these hard dental tissues for future research. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to map the distribution of multiple trace elements and heavy metals across equine healthy and diseased (hypercementosis-affected) hard dental tissues among four teeth extracted from horses with EOTRH. Results showed banding patterns of some trace elements (lead, strontium, barium), reflecting the temporal component of accumulation of trace elements during dentin mineralization. Essential elements zinc and magnesium did not show banding patterns. Comparison to the unaffected cementum and dentin adjacent to the hypercementosis region showed that there is an underlying incremental pattern in the uptake of some metals with spatial irregularities. This supports a possible metabolic change involved in hypercementosis lesion development. This represents the first use of LA-ICP-MS to study the microspatial distribution of trace elements in equine teeth, establishing a baseline for elemental distribution in normal and EOTRH impacted dental hard tissue.

Elemental composition of the hair and milk of black-spotted cows and its relationship with intestinal microbiome reorganization

Background and Aim

The cattle breeding system is facing severe problems associated with the increased negative impact of various human activity areas on the environment and the bodies of farm animals. The use of heavy metals in different production areas leads to their accumulation in the environment due to the ingestion of animals and humans through animal products. This study aimed to assess the elemental composition of the hair and milk of black-spotted cows and to identify the relationship between the content of toxic and essential elements and the state of the intestinal microbiome.

Materials and Methods

The element status was estimated by studying the chemical composition of the biosubstrates using inductively coupled plasma-mass spectroscopy. Based on the analysis of hair, the elemental composition, and the use of the coefficient of toxic load, two groups of animals were formed: Group I, which included cows with a lower load factor, and Group II, which included cows with a higher load factor.

Results

An increase in the heavy metal concentrations in the hair and milk of animals in Group II was observed. The As, Fe, Pb, Al, Co, Ni, and V concentrations in the hair of cows from Group II increased relative to Group I by 19%, 29%, 24.5%, 32.3%, 35.6%, 21.5%, and 18.2%, respectively. There was a significant increase in the level of Fe by 11.5%, Cr by 8.25%, Mn by 17.6%, Pb by 46.1%, and Cd by 25% in Group II compared with Group I in the assessment of elemental milk composition. There were no apparent changes in the intestinal microbiome of Group II.

Conclusion

Some heavy metals were accumulated in the bodies and milk of animals. This shows a high probability of heavy metals causing harm to the health of animals and humans.

Concentration of Selected Essential and Toxic Trace Elements in Horse Hair as an Important Tool for the Monitoring of Animal Exposure and Health

The main purpose of the study was to analyse the concentrations of selected essential and toxic trace elements in the hair of sports and recreational riding horses from studs located in central Poland and thus test the usefulness of this matrix for monitoring the exposure of these animals. We also measured the concentration of heavy metals in oats used as a basic component of the equine diet to investigate the interactions between these elements in the feed and hair. The basic chemical composition of oats was analysed. Elemental analysis was performed using an EcaFlow 150 GLP electrochemical analyser with an E-104L electrode and reference to a calibration curve. The chemical composition of oats was investigated by near infrared transmission (NIR) spectroscopy calibrated for an artificial neural network (ANN) using a Foss InfraXact spectrometer. Among all elements, the coefficient of variation was highest for Pb and lowest for Cd, regardless of the study group. The content of elements in horse hair was in the range of 153.56 to 185.79 mg·kg^-1 for Zn, 6.10 to 11.99 mg·kg^-1 for Cu, 0.578 to 0.813 mg·kg^-1 for Pb and 0.011 to 0.015 mg·kg^-1 for Cd (in kg of d.w.). For hair, we found a significant negative correlation for Zn-Cu (r_xy = -0.539) and Cd-Cu (r_xy = -0.676) at p ≤ 0.05. For feed, there was a highly significant positive correlation for Cu-Pb (r_xy = 0.723) and Zn-Cd (r_xy = 0.714) at p ≤ 0.01. We found significant negative oats-hair interactions for Cu-Zn, Pb-Cu, Cd-Cu and Zn-Pb, and a positive oats-hair interaction for Cu-Cu.

The total accumulation of heavy metals in body in connection with the dairy productivity of cows

Monitoring of health status and metabolism of dairy cows is essential for modern milk production. At the current level of productivity of dairy cows, in addition to essential elements, increasing attention must be paid to controlling the exchange of toxic elements, a significant number of which belong to the category of heavy metals. In this regard, the objective of our research was to study the relationship of pools of heavy metals in the body of dairy cows, evaluated according to hair composition and elemental composition of blood serum and milk productivity of animals. Assessment of trace element content in the samples was performed using inductively coupled plasma mass spectrometry (ICP-MS). Fat and protein content in milk was assessed by the FIL-IDF procedure. In order to assess the metabolic load of chemical elements in body of cows, the coefficient of total load C_load was calculated. It allowed us to divide all animals into three groups. Assessment of the content of 25 chemical elements in hair of cows revealed a general regularity of increase in average statistical values of concentrations of some elements with increasing load from 6.9 in group I to 10.7 in group II and 15.8 in group III. As C_load grew from 10.7 in group II to 15.8 in group III, the content of 20 chemical elements in the coat of animals from group III exceeded that in group II. Exceptions were only Ca, K, P, Se, and As. Thus, the productivity of dairy cows turned out to be interconnected not so much with the level of heavy metals (9 elements), but with a wider list of 20-23 chemical elements. Thus, the optimal course of metabolic processes in animal organism, coupled with the highest productivity, is possible when the internal environment of body is saturated with a certain amount of chemical elements. Accordingly, a lack or excess of these substances will be associated with a decrease in the efficiency of metabolism and animal productivity.