Analysis in horse hair as a means of evaluating selenium toxicoses and long-term exposures

Understanding the Effect of Single Atom Cationic Defect Sites in an Al2O3 (012) Surface on Altering Selenate and Sulfate Adsorption: An Ab Initio Study

Adsorption is a promising under-the-sink selenate remediation technique for distributed water systems. Recently it was shown that adsorption induced water network re-arraignment control adsorption energetics on the α - Al 2 O 3 (012) surface. Here, we aim to elucidate the relative importance of the water network effects and surface cation identity on controlling selenate and sulfate adsorption energy using density functional theory calculations. Density functional theory (DFT) calculations predicted the adsorption energies of selenate and sulfate on nine transition metal cations (Sc-Cu) and two alkali metal cations (Ga and In) in the α - Al 2 O 3 (012) surface under simulated acidic and neutral pH conditions. We find that the water network effects had larger impact on the adsorption energy than the cationic identity. However, cation identity secondarily controlled adsorption. Most cations decreased the adsorption energy weakening the overall performance, the larger Sc and In cations enabled inner-sphere adsorption in acidic conditions because they relaxed outward from the surface providing more space for adsorption. Additionally, only Ti induced Se selectivity over S by reducing the adsorbing selenate to selenite but not reducing the sulfate. Overall, this study indicates that tuning water network structure will likely have a larger impact than tuning cation-selenate interactions for increasing adsorbate effectiveness.

Biomarkers and their potential for detecting livestock plant poisonings in Western North America

The United States National Cancer Institute defines a biomarker as: "A biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease." In Veterinary Medicine, biomarkers associated with plant poisonings of livestock have great utility. Since grazing livestock poisoned by toxic plants are often found dead, biomarkers of plant poisoning allow for a more rapid postmortem diagnosis and response to prevent further deaths. The presence and concentration of toxins in poisonous plants are biomarkers of risk for livestock poisoning that can be measured by the chemical analysis of plant material. More difficult is, the detection of plant toxins or biomarkers in biological samples from intoxicated or deceased animals. The purpose of this article is to review potential biomarkers of plant poisoning in grazing livestock in the Western North America including recently investigated non-invasive sampling techniques. Plants discussed include larkspur, lupine, water hemlock, swainsonine-containing plants, selenium-containing plants, and pyrrolizidine alkaloid containing plants. Other factors such as animal age and sex that affect plant biomarker concentrations in vivo are also discussed.

Evaluation of hair analysis for determination of trace mineral status and exposure to toxic heavy metals in horses in the Netherlands

Analysis of hair to gain insight into the trace mineral status and exposure to toxic heavy metals of horses is attractive because hair is an easily accessible sample material. To investigate the potential value of hair analysis in horses for determination of trace mineral and heavy metal concentrations, we analyzed mane hair and liver samples from 62 horses presented for slaughter at a facility in the Netherlands that receives horses from all regions of the country. Hair samples were cleaned in warm water. After acid digestion of hair and liver specimens, we quantified, with inductively coupled plasma-mass spectrometry, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, selenium, vanadium, and zinc in the digests. Based on Pearson product moment correlations, we found no statistically significant correlations between concentrations of trace minerals in liver and hair, with the exception of a slight correlation for copper that was too weak to be of clinical relevance. Our results do not support the use of hair to determine trace mineral status and exposure to toxic heavy metals in the horse under field conditions.

Diet and dog characteristics affect major and trace elements in hair and blood of healthy dogs

Obtaining correct amounts of essential elements, and avoiding toxic metals are key factors in dog health. Through analyzing major and trace elements in hair and blood of 50 healthy companion dogs using ICP-MS, we study their associations with dog characteristics and diet, hypothesizing that eating the same diet long-term results in strong correlations between hair and blood element concentrations, and that dog characteristics and diet affect element status. The correlation between hair and blood was significant for Hg (R = 0.601, p = 0.000) and Pb (R = 0.384, p = 0.010). The following associations were significant (p < 0.05): Dark hair had higher Ca and Mg compared to light hair. Females had higher hair Zn, blood Mn, and blood As compared to males. Blood Mn and Se increased, while blood Pb decreased with age. Raw diet fed dogs had higher hair Zn and Se compared to dry or mixed diet fed dogs, and lower blood Mn compared to dry diet fed dogs. Dry and mixed diet fed dogs had higher blood Cd compared to raw diet fed dogs. Mixed diet fed dogs had higher hair Ca and Mg compared to raw or dry diet fed dogs, and higher hair Pb compared to dry diet fed dogs. Wild game consumption was associated with higher blood Pb, and rice consumption with higher blood As. In conclusion, hair provides an alternative for assessing Hg and Pb exposure, and major and trace elements status is affected by hair color, sex, age, and diet.

"Feeding the Foot": Nutritional Influences on Equine Hoof Health

Nutrition plays an important role in equine health, including that of the foot. Deficiencies and excesses of dietary components can affect the growth and function of the foot and have been associated with important podiatric diseases. The recognition, prevention, and treatment of specific notable nutritional diseases of the foot are discussed, as well as information regarding specific ingredients included in supplements meant to improve equine hoof quality. Ensuring provision of a balanced diet, maintaining horses in appropriate body condition, and seeking guidance from an equine nutritionist when creating dietary recommendations will prevent most equine foot disease related to nutrition.

Plant-Induced Myotoxicity in Livestock

Many toxic plants, ingested by livestock while grazing or eating contaminated processed feed, produce myoskeletal or myocardial lesions that sometimes have irreversible consequences. Some myotoxic plants are lethal after ingestion of very small amounts whereas others require consumption for many days to several weeks to produce disease. Incorporation of field studies, clinical signs, gross and microscopic pathology, and chemical identification of plants, toxins, and metabolites in animal samples is essential for an accurate diagnosis. This review introduces toxic plants that cause myotoxicity, reviews toxins and lesions, discusses analyses for making an accurate diagnosis, and summarizes treatments and recommendations to avoid future poisonings.

Selenosis in Ruminants

Selenium (Se) is a metalloid that exists as a red amorphous powder, reddish crystal, silver-gray crystal, or brown-black solid. Its potency as a nutrient and a toxicant is such that few people have seen the pure element. It is easy to lose sight of the narrow margin between too little and too much. The most common cause of selenosis is accidental or intentional overuse of supplements. Many target organs and effects of Se toxicity are similar to those of Se deficiency, so laboratory confirmation is necessary. Prevention consists of minimizing exposure to seleniferous feedstuffs and optimizing dietary factors that might aggravate selenosis.

The acute toxicity of water hemlock (Cicuta douglasii) in a goat model

Water hemlock (Cicuta douglasii) is one of the most toxic plants to livestock and humans. Little is known regarding the amount of plant required to cause death. The objective of this study was to determine a lethal dose of water hemlock in a goat model. Plants were dosed to goats via oral gavage of freeze-dried ground plant material. The results from this study suggest that 1-2 fresh tubers would be lethal to goats.

Assessment of Gender Effects and Reference Values of Mane Hair Trace Element Content in English Thoroughbred Horses (North Caucasus, Russia) Using ICP-DRC-MS

The objective of the present study was assessment of gender differences in hair trace element content in English Thoroughbred horses (North Caucasus, Russia) using ICP-DRC-MS and calculation of the reference values. Trace element content in mane hair of 190 stallions and 94 mares (3-7 years old) bred in North Caucasus (Russia) was assessed using inductively coupled plasma mass spectrometry. Mane hair Co, Cr, Mn, Li, Si, and Sr levels in mares exceeded those in stallions by 77%, 63%, 64%, 42%, 39%, and 64%, respectively. Hair Fe and Si content was nearly twofold higher in female horses as compared to the males. Only hair Zn content was 5% higher in stallions as compared to mares. In addition, mares were characterized by 63%, 65%, 29%, and 40% higher levels of As, Pb, Sn, and Ni levels in hair as compared to the respective values in stallions. In turn, hair Al and Hg were more than twofold higher in mares than in stallions. The reference intervals of mane hair content (μg/g) for Co (0.006-0.143), Cr (0.028-0.551), Cu (4.17-6.84), Fe (10.11-442.2), I (0.026-3.69), Mn (0.551-12.55), Se (0.108-0.714), Zn (97.43-167), Li (0.011-0.709), Ni (0.060-0.589), Si (0.665-29.12), V (0.006-0.584), Al (1.98-168.5), As (0.006-0.127), Cd (0.002-0.033), B (0.494-16.13), Pb (0.018-0.436), Sn (0.002-0.144), Sr (1.0-9.46), and Hg (0.0018-0.017) in the total cohort of horses were estimated using the American Society for Veterinary Clinical Pathology Quality Assurance and Laboratory Standard Guidelines. The reference intervals were also estimated for stallions and mares bred in North Caucasus (Russia) and may be used for interpretation of the results of hair trace element analysis in horses.

The content of toxic elements in hair of dairy cows as an indicator of productivity and elemental status of animals

The study was conducted on a model of dairy cows of the Holstein breed. At the first stage of research, the elemental composition of cow hair was studied (n = 198). Based on this study, the percentile intervals of chemical elements concentrations in hair were established; values of 25 and 75 percentiles were determined, and they were considered as "physiological standard." At the second stage, the elemental composition of hair from the upper part of withers of highly productive Holstein cows during the period of increasing milk yield was analyzed (n = 47). The elemental composition of biological substrates was studied according to 25 indicators, using the methods of atomic emission and mass spectrometry (AES-ICP and MS-ICP). An assessment of productivity parameters of cows depending on the level of toxic elements in hair revealed a negative statistically significant relationship with the level of lead. Lead content in hair was negatively correlated with the yield of fat (r = - 0.50), protein (r = - 0.37), and dry matter (r = - 0.48) in milk. Based on these data, cows were divided into three groups: group I, with Pb concentration in hair 0.0245-0.0449 mg/g, group II-between 0.0495 and 0.141 mg/kg, and in group III-between 0.145 and 0.247 mg/g. It was established that increasing Pb content decreases daily production of milk fat by 18.8 (P ≤ 0.05) and 25.3% (P ≤ 0.05), protein by 9.7 (P ≤ 0.05) and 10.7% (P ≤ 0.05), and dry matter by 8.0 and 13.0% (P ≤ 0.05) in cows. Average daily milk yield, adjusted for 1% of fat, decreased by 19.2 (P ≤ 0.05) and 25.3% (P ≤ 0.05), respectively. As the concentration of lead in hair increased, the content of toxic elements (Al, As, Cd, Hg, Pb, Sn, Sr) increased from 0.07 to 0.235 mmol/kg in group I, in group II from 0.082 to 0.266 mmol/kg, and in group III-from 0.126 to 0.337 mmol/kg. It was concluded that it is necessary to further study the use of physiological standard indicators of the content of toxic chemical elements in hair of dairy cows to increase productivity and maintain animal health and to create an effective system of individual health monitoring of highly productive cattle.

An Evaluation of Hair, Oral Fluid, Earwax, and Nasal Mucus as Noninvasive Specimens to Determine Livestock Exposure to Teratogenic Lupine Species

The livestock industry in the western United States loses an estimated $500 million annually from livestock production losses due to poisonous plants. Poisoning of livestock by plants often goes undiagnosed because there is a lack of appropriate or available specimens for analysis. The Lupinus species represent an important toxic plant in western North America that can be toxic and/or teratogenic to livestock species due to the quinolizidine alkaloids. The objective of this study was to evaluate the potential of using earwax, hair, oral fluid, and nasal mucus as noninvasive specimens to determine livestock exposure to the teratogenic Lupinus species. Quinolizidine alkaloids were detected in these four matrices in cattle that were administered a single dose of Lupinus leucophyllus. In addition, quinolizidine alkaloids from lupine were detected in the earwax of cattle that grazed on lupine-infested rangelands. This study demonstrates the potential of earwax, hair, oral fluid, and nasal mucus as noninvasive specimens for chemical analyses to aid in the diagnosis of livestock that may have been exposed to and poisoned by plants.

Long-term monitoring of opioid, sedative and anti-inflammatory drugs in horse hair using a selective and sensitive LC-MS/MS procedure

Background

Compared to blood or urine, drugs can be detected for much longer periods in the long hair of horses. The aim of this study was to establish and validate a highly sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the detection and quantification of frequently prescribed opioids, sedatives and non-steroidal anti-inflammatory agents in the mane and tail hair of horses. Based on an average growth rate of about 2 cm per month, times of administration reported by horse owners or veterinary physicians were related to drug localizations in hair. Hair samples were collected from ten horses that received drug treatments and analyzed in segments of 2, 4 or 6 cm in length. Hair segments were decontaminated, cut into fragments and methanol-extracted under sonication. The extracts were analyzed by LC-MS/MS for 13 commonly used drugs using the validated procedure. Deuterated analogs were included as internal standards.

Results

Analytes were detected in hair samples with a length of up to 70 cm. Fourteen out of 16 hair samples were positive for at least one of the tested drugs. Segmentation allowed for time-resolved monitoring of periods of 1 to 3 months of drug administration. Concentrations in dark hair reached a maximum of 4.0 pg/mg for butorphanol, 6.0 pg/mg for tramadol, 1.4 pg/mg for morphine, 1.8 pg/mg for detomidine, 1.2 pg/mg for acepromazine, 39 pg/mg for flunixin, 5.0 pg/mg for firocoxib, and 3’600 pg/mg for phenylbutazone. Only trace amounts of meloxicam were detected. Drug detection correlated well with the reported period of medical treatment. No analytes were detected in the light-colored mane and tail hair samples from one horse despite preceding administrations of acepromazine and phenylbutazone.

Conclusion

This study describes a sensitive and selective technique suitable for the validated detection and quantification of frequently prescribed veterinary drugs in horse hair. The segmental method can be applied for time-resolved long-term retrospective drug monitoring, for example in prepurchase examinations of horses as drug detection in hair can prove preceding medical treatments.