Lupine induced "crooked calf disease" in Washington and Oregon: identification of the alkaloid profiles in Lupinus sulfureus, Lupinus leucophyllus, and Lupinus sericeus

The use of earwax to determine livestock exposure to teratogenic lupine

Lupines (Lupinus spp.) are a common plant species on western U.S. rangelands with several lupine species containing alkaloids that can be toxic and/or teratogenic to livestock. In North America, more than 150 lupine species are recognized with some ranches or grazing allotments containing multiple species. One or more of these lupine species may contain alkaloids that are teratogenic to cattle. Previous work has shown that lupine alkaloids can be detected in earwax of cattle grazing lupine infested rangelands. Our hypothesis is that earwax can be used to determine if cattle have been exposed to teratogenic alkaloids from multiple lupine species. Two lupine species, L. sericeus and L. polyphyllus, were present on a rangeland in east-central Idaho. The teratogen, anagyrine, was detected in L. sericeus and the teratogen, ammodendrine, was detected in L. polyphyllus plants collected on this rangeland. In this study, earwax was collected from 69 pregnant cows that had previously grazed a rangeland containing two different lupine species containing alkaloids that cause crooked calf syndrome (CCS). Anagyrine was detected in the earwax of all 69 cows sampled. Ammodendrine, was detected in the earwax of 28 of the 69 cows sampled. Earwax is a good non-invasive sample to aid in the diagnosis of cattle that have consumed lupine and does appear, in this case, to be a good diagnostic tool to differentiate between more than one lupine species that may be the cause of CCS. Concentrations of anagyrine or ammodendrine did not correlate with the incidence of CCS.

Lupine-induced crooked calf syndrome: mitigation through intermittent grazing management of cattle

Lupines are responsible for a condition in cattle referred to as "crooked calf syndrome" (CCS) that occurs when pregnant cattle graze teratogenic lupines. A proposed management strategy to limit these types of birth defects includes utilizing an intermittent grazing schedule to allow short durations of grazing lupine-infested areas interrupted by movement to a lupine-free pasture. The objective of this study was to determine if an intermittent schedule of ten continuous days of lupine treatment followed by 5 d off treatment would be sufficient to decrease, or prevent, the incidence of lupine-induced malformations. Continuous dosing of the teratogenic lupine (Lupinus leucophyllus) to pregnant cows for 30 d during the most susceptible stage of pregnancy (gestation days 40 to 70) resulted in severe skeletal birth defects in their calves. However, intermittent dosing of the teratogenic lupine demonstrated that interrupted intake of lupine reduced the severity, or eliminated, permanent skeletal malformations in calves born to cows dosed lupine. Toxicokinetic and ultrasound data demonstrated a clear inverse correlation between serum anagyrine (the primary teratogenic alkaloid in some lupines) concentrations in the dam and fetal movement. In the intermittent group, fetal movement quickly returned to normal after lupine feeding stopped and remained normal until lupine treatment resumed. Therefore, interrupting lupine intake for at least 5 d through an intermittent grazing program could reduce the severity of the CCS. Furthermore, this method would allow ranchers to move cattle back into lupine pastures after a brief interruption, which would allow for more efficient utilization of forage resources.

Acute death as a result of poisoning tropical (Bos taurus indicus) but not temperate (Bos taurus taurus) cattle after oral dosing with Lupinus leucophyllus (velvet lupine)

Due to climate change and increasing summer temperatures, tropical cattle may graze where temperate cattle have grazed, exposing tropical cattle to toxic plants they may be unfamiliar with. This work compared the toxicity of Lupinus leucophyllus (velvet lupine) in temperate and tropical cattle. Orally dosed velvet lupine in tropical cattle caused death. If producers opt to graze tropical cattle, additional care must be taken on rangelands where toxic lupines like velvet lupine grow.

Consequences of pollen defense compounds for pollinators and antagonists in a pollen-rewarding plant

Plants produce an array of defensive compounds with toxic or deterrent effects on insect herbivores. Pollen can contain relatively high concentrations of such defense compounds, but the causes and consequences of this enigmatic phenomenon remain mostly unknown. These compounds could potentially protect pollen against antagonists but could also reduce flower attractiveness to pollinators. We combined field observations of the pollen-rewarding Lupinus argenteus with chemical analysis and laboratory assays to test three hypotheses for the presence of pollen defense compounds: (1) these compounds are the result of spillover from adjacent tissues, (2) they protect against pollen thieves, and (3) they act as antimicrobial compounds. We also tested whether pollen defense compounds affect pollinator behavior. We found a positive relationship between alkaloid concentrations in pollen and petals, supporting the idea that pollen defense compounds partly originate from spillover. However, pollen and petals exhibited quantitatively (but not qualitatively) distinct alkaloid profiles, suggesting that plants can adjust pollen alkaloid composition independently from that of adjacent tissues. We found no relationship between pollen alkaloid concentration and the abundance of pollen thieves in Lupinus flowers. However, pollen alkaloids were negatively associated with bacterial abundance. Finally, plants with more alkaloids in their pollen received more pollinator visits, but these visits were shorter, resulting in no change in the overall number of flowers visited. We propose that pollen defense compounds are partly the result of spillover from other tissues, while they also play an antimicrobial role. The absence of negative effects of these compounds on pollinator visitation likely allows their maintenance in pollen at relatively high concentrations. Taken together, our results suggest that pollen alkaloids affect and are mediated by the interplay of multiple interactions.

Upcycling post-harvest biomass residues from native European Lupinus species: from straws and pod shells production to nutritive value and alkaloids content for ruminant animals

The production of Lupinus seeds for food and feed is increasing worldwide, which results in large amounts of post-harvest biomass residues, considered of low value and left in the field to be burned or incorporated in the soil. To valorize these agricultural wastes, this work aimed to assess their potential as an alternative feed for ruminants. Thus, the production yield, nutritive value, and alkaloid content of straws and pod shells from three native European Lupinus species, L. albus 'Estoril' (white), L. angustifolius 'Tango' (narrow-leafed), and L. luteus 'Cardiga' (yellow), cultivated in two locations, were evaluated. The dry matter (DM) yield of straws and pod shells were the highest for L. albus 'Estoril' (4.10 t ha^-1) and the lowest for L. angustifolius 'Tango' (1.78 t ha^-1), suggesting a poor adaptation of narrow-leafed lupin to the particularly dry and warm agronomic year. Despite species-specific differences, lupin biomass residues presented higher crude protein (53.0-68.9 g kg^-1 DM) and lignin (103-111 g kg^-1 DM) content than cereal straws usually used in ruminant feeding, thus resulting in higher metabolizable energy (6.43-6.58 MJ kg^-1 DM) content. In vitro digestibility was similar among lupin species (47.7-50.6%) and higher in pod shells (53.7%) than in straws (44.6%). Lupinus albus 'Estoril' and L. luteus 'Cardiga' presented considerable amounts of alkaloids in straws (23.9 and 119 mg kg^-1 DM) and pod shells (20.5 and 298 mg kg^-1 DM), while no alkaloids were detected in L. angustifolius 'Tango' biomass residues. Considering the combined production of straw and pod shells per lupin species, it is anticipated that lupin biomass residues produced per ha can fulfill 85% of the energy and nearly 50% of protein requirements of a flock of 4 to 9 dry and mid-pregnancy sheep with 50 kg body weight for one year. No negative effects on small (ovine) and large (bovine) ruminant species due to alkaloids are expected, even if biomass residues are consumed at up to 85% DM intake. The large production yield along with its nutritive value unveils the potential of lupin biomass residues valorization as alternative fodder for ruminants, promoting sustainability under a circular economy approach.

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.

Use of Herbarium Voucher Specimens To Investigate Phytochemical Composition in Poisonous Plant Research

Poisonous plants cause large losses to the livestock industry through death, reduced production efficiency, reproductive dysfunction, and compromised harvesting of rangeland and pasture forages. Research investigating poisonous plants is complex because there are hundreds of genera of toxic plants representing thousands of species. To investigate the effects of poisonous plants on livestock, a clear understanding of the taxonomic identity of the plant and the ability to collect the plant in sufficient quantities for scientific studies is required. Subsequently, the active principles must be defined and investigated in the taxa of interest to better predict risk and make recommendations to reduce losses. Herbaria are collections of preserved plant specimens and are an important resource in poisonous plant research. Voucher specimens have often been used in the identification of the plant for the experimental reproduction of suspected livestock poisoning associated with a spontaneous case. More recently, herbarium specimens have been used to investigate the chemical composition of toxic plants as well as the distribution of different chemotypes over the landscape. The primary purpose of this review is to highlight the chemical analysis of herbarium specimens in poisonous plant research.

Pollen and vegetative secondary chemistry of three pollen-rewarding lupines

PREMISE

Optimal defense theory predicts that selection should drive plants to disproportionally allocate resources for herbivore defense to tissues with high fitness values. Because pollen's primary role is the transport of gametes, plants may be expected to defend it from herbivory. However, for many animal-pollinated plants, pollen serves a secondary role as a pollinator reward. These dual roles may present a conflict between selection to defend pollen from herbivores and selection to reward pollinators. Here, we investigate whether pollen secondary chemistry in three pollen-rewarding Lupinus species better reflects the need to defend pollen or reward pollinators.

METHODS

Lupinus (Fabaceae) species are nectarless, pollen-rewarding, and produce defensive quinolizidine and/or piperidine alkaloids throughout their tissues. We used gas chromatography to identify and quantitate the alkaloids in four aboveground tissues (pollen, flower, leaf, stem) of three western North American lupines, L. argenteus, L. bakeri, and L. sulphureus, and compared alkaloid concentrations and composition among tissues within individuals.

RESULTS

In L. argenteus and L. sulphureus, pollen alkaloid concentrations were 11-35% of those found in other tissues. We detected no alkaloids in L. bakeri pollen, though they were present in other tissues. Alkaloid concentrations were not strongly correlated among tissues within individuals. We detected fewer alkaloids in pollen compared to other tissues, and pollen contained no unique alkaloids.

CONCLUSIONS

Our results are consistent with the hypothesis that, in these pollen-rewarding species, pollen secondary chemistry may reflect the need to attract and reward pollinators more than the need to defend pollen from herbivory.

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.

Genetic Relationships among Different Chemotypes of Lupinus sulphureus

Lupines (Lupinus spp.) are a common plant legume species found on western U.S. rangelands. Lupinus spp. may contain quinolizidine and/or piperidine alkaloids that can be toxic and/or teratogenic to grazing livestock. Alkaloid profiles may vary between and within a species. The objectives of this study were to (1) further explore the characteristic alkaloid profiles of Lupinus sulphureus using field collections and (2) explore the phylogenetic relationship of the different populations and chemotypes of L. sulphureus using the amplified fragment length polymorphism method of DNA fingerprinting, thus providing possible explanations to the phenomena of multiple chemotypes within a species. A total of 49 accessions of L. sulphureus were classified into seven chemotypes. The DNA profiles showed that one L. sulphureus chemotype, chemotype A, is genetically divergent from the other chemotypes of L. sulphureus, suggesting that it represents an unresolved lupine taxon, possibly a new lupine species. Additionally, the different chemotypes of L. sulphureus represented different genetic groups, as shown by Bayesian cluster analysis and principle component analysis.

Anagyrine desensitization of peripheral nicotinic acetylcholine receptors. A potential biomarker of quinolizidine alkaloid teratogenesis in cattle

Anagyrine, a teratogenic quinolizidine alkaloid found in Lupinus spp., is proposed to undergo metabolism by pregnant cattle to a piperidine alkaloid which inhibits fetal movement, the putative mechanism behind crooked calf syndrome. The objective of this study was to test the hypothesis that anagyrine but not lupanine or sparteine can directly, without metabolism, desensitize nicotinic acetylcholine receptors (nAChR) in a cell culture model. SH-SY5Y cells expressing autonomic nAChR, and TE-671 cells expressing fetal muscle-type nAChR were exposed to lupine alkaloids or Dimethylphenylpiperazinium (DMPP) in log₁₀ molar increments from 10nM to 100μM and then to a fixed concentration of acetylcholine (ACh) (10μM for SH-SY5Y cells and 1μM for TE-671 cells) and the responses measured with a membrane potential sensing dye to assess nAChR activation and desensitization. The selective ganglionic nAChR agonist DMPP used as a positive control, was a potent activator and desensitizer of nAChR expressed by SH-SY5Y cells. Lupanine was a weak agonist and desensitizer in SH-SY5Y cells and sparteine was without effect. Anagyrine acted as a partial agonist in both cell lines with EC₅₀ values of 4.2 and 231μM in SH-SY5Y and TE-671 cells, respectively. Anagyrine was a desensitizer of nAChR with DC₅₀ values of 6.9 and 139μM in SH-SY5Y and TE-671 cells, respectively. These results confirm the hypothesis that anagyrine is a potent and effective desensitizer of nAChR, and that anagyrine can directly, without metabolism, desensitize nAChR. Moreover, serum anagyrine concentrations may be a potential biomarker for lupine teratogenicity in cattle.

Differences between Angus and Holstein cattle in the Lupinus leucophyllus induced inhibition of fetal activity

Calves with congenital defects born to cows that have grazed teratogenic Lupinus spp. during pregnancy can suffer from what is termed crooked calf syndrome. Crooked calf syndrome defects include cleft palate, spinal column defects and limb malformations formed by alkaloid-induced inhibition of fetal movement. In this study, we tested the hypothesis that there are differences in fetal activity of fetuses carried by Holstein verses Angus heifers orally dosed with 1.1 g/kg dried ground Lupinus leucophyllus. Fetal activity was monitored via transrectal ultrasonography and maternal serum was analyzed for specific lupine alkaloids. There were more (P < 0.05) movements in fetuses of Holstein heifers than those in Angus heifers at eight and 12 h after oral dosing. In addition to serum alkaloid toxicokinetic differences, the Holstein heifers had significantly lower serum concentrations of anagyrine at 2, 4, and 8 h after oral dosing than Angus heifers. Holstein heifers also had significantly greater serum concentrations of lupanine at 12, 18 and 24 h after dosing than the Angus heifers. These results suggest that there are breed differences in susceptibility to lupine-induced crooked calf syndrome. These differences may also be used to discover genetic markers that identify resistant animals, thus facilitating selective breeding of resistant herds.

Approach to Investigating Congenital Skeletal Abnormalities in Livestock

Congenital skeletal abnormalities may be genetic, teratogenic, or nutritional in origin; distinguishing among these different causes is essential in the management of the disease but may be challenging. In some cases, teratogenic or nutritional causes of skeletal abnormalities may appear very similar to genetic causes. For example, chondrodysplasia associated with intrauterine zinc or manganese deficiency and mild forms of hereditary chondrodysplasia have very similar clinical features and histologic lesions. Therefore, historical data are essential in any attempt to distinguish genetic and acquired causes of skeletal lesions; as many animals as possible should be examined; and samples should be collected for future analysis, such as genetic testing. Acquired causes of defects often show substantial variation in presentation and may improve with time, while genetic causes frequently have a consistent presentation. If a disease is determined to be of genetic origin, a number of approaches may be used to detect mutations, each with advantages and disadvantages. These approaches include sequencing candidate genes, single-nucleotide polymorphism array with genomewide association studies, and exome or whole genome sequencing. Despite advances in technology and increased cost-effectiveness of these techniques, a good clinical history and description of the pathology and a reliable diagnosis are still key components of any investigation.

Global perspectives on poisonous plants: the 9th international symposium on poisonous plants

The 9th International Symposium on Poisonous Plants (ISOPP9) was held July 15-21, 2013, at the Inner Mongolia Agricultural University in Hohhot, Inner Mongolia Autonomous Region of China. The symposium consisted of three days of oral and poster presentations, followed by a tour of the Xilinhot Region of the Mongolian Grasslands, encompassing grazing conditions consisting of desert, grassland, and steppes. This was the first time that an ISOPP meeting has been held in Asia and provided an opportunity for visitors from outside China to become aware of livestock poisonings caused by plant species with which they were previously not familiar while at the same time demonstrating that many of the problems experienced around the world have a common etiology. Presentations focused on botany, veterinary science, toxicology, mechanism of action, and chemistry. As is appropriate for the Journal of Agricultural and Food Chemistry, this cluster of papers consists of selected oral and poster presentations in which the chemistry of the toxins played a significant role. The symposium revealed that there is considerable scope for isolation, structural elucidation, and analysis of the toxins from the numerous poisonous plant species that have been identified in China. It became apparent that there are abundant opportunities for chemists both within China and abroad to collaborate with Chinese scientists working on biological aspects of livestock poisonings.

How a phosphorus-acquisition strategy based on carboxylate exudation powers the success and agronomic potential of lupines (Lupinus, Fabaceae)

Lupines (Lupinus species; Fabaceae) are an ancient crop with great potential to be developed further for high-protein feed and food, cover crops, and phytoremediation. Being legumes, they are capable of symbiotically fixing atmospheric nitrogen. However, Lupinus species appear to be nonmycorrhizal or weakly mycorrhizal at most; instead some produce cluster roots, which release vast amounts of phosphate-mobilizing carboxylates (inorganic anions). Other lupines produce cluster-like roots, which function in a similar manner, and some release large amounts of carboxylates without specialized roots. These traits associated with nutrient acquisition make lupines ideally suited for either impoverished soils or soils with large amounts of phosphorus that is poorly available for most plants, e.g., acidic or alkaline soils. Here we explore how common the nonmycorrhizal phosphorus-acquisition strategy based on exudation of carboxylates is in the genus Lupinus, concluding it is very likely more widespread than generally acknowledged. This trait may partly account for the role of lupines as pioneers or invasive species, but also makes them suitable crop plants while we reach "peak phosphorus".

Alkaloid Profiling as an Approach to Differentiate Lupinus garfieldensis, Lupinus sabinianus and Lupinus sericeus

INTRODUCTION

Many species in the Lupinus genus are poorly defined morphologically, potentially resulting in improper taxonomic identification. Lupine species may contain quinolizidine and/or piperidine alkaloids that can be acutely toxic and/or teratogenic, the latter resulting in crooked calf disease.

OBJECTIVE

To identify characteristic alkaloid profiles of Lupinus sabinianus, L. garfieldensis and L. sericeus which would aid in discriminating these species from each other and from L. sulphureus.

METHODS AND MATERIALS

Quinolizidine and piperidine alkaloids were extracted from herbarium specimens and recent field collections of L. sabinianus, L. garfieldensis and L. sericeus. The alkaloid composition of each species was defined using GC-FID and GC-MS and compared using multivariate statistics.

RESULTS

Each of the three species investigated contained a diagnostic chemical fingerprint composed of quinolizidine and/or piperidine alkaloids.

CONCLUSION

The alkaloid profiles of Lupinus sabinianus, L. garfieldensis and L. sericeus can be used as a tool to discriminate these species from each other and L. sulphureus as long as one considers locality of the collection in the case of L. sabinianus.

A Chemical Marker Proposal for the Lantana genus: Composition of the Essential Oils from the Leaves of Lantana radula and L. canescens

Essential oil extracts from the leaves of two Lantana species ( L. radula Sw. and L. canescens Kunth), for which no prior analysis has been reported, were analyzed by GC-MS. This information was utilized to propose chemical markers for Lantana species so that identification between physically similar plant species can be achieved through chemical analysis. Results showed 33 constituents for L. canescens, among which β-caryophyllene (43.9%), β-cubebene (10.1%), elixene (8.6%), β-phellandrene (6.1%), α-caryophyllene (2.6%) and dehydro-aromadendrene (2.6%) were the principle components. L. radula revealed the presence of 21 compounds, the most abundant of which were β-cubebene (31.0%), β-caryophyllene (20.8%), elixene (10.0%), α-salinene (6.4%), β-phellandrene (6.1%), copaene (4.9%) cadinene (1.4%) and psi-limonene (1.4%). The high concentration of β-caryophyllene in the samples tested here and those in the literature make it a good candidate for a chemical marker for Lantana species, with β-cubebene, elixene and β-phellandrene following as minor compounds identified more sporadically in this genus. On the other hand, Lippia species, which are morphologically similar to those from the Lantana genus, would contain limonene, citral, carvacrol, β-myrcene, camphor and thymol as the main chemical markers. These chemical markers would be a powerful tool for maintaining quality control in the extraction of essential oils for use in medicinal applications, as well as in identification of plant specimens to a taxonomist.

Changes in Lupinus albus and Lupinus angustifolius alkaloid profiles in response to mechanical damage

The aim of this work was to evaluate chemical responses to biomass removal mimicking large herbivore action in Lupinus albus and Lupinus angustifolius aerial parts. GC and GC-MS were used to determine total alkaloid content (TAC) and alkaloid relative abundances in bitter and sweet varieties of each species. Bitter genotypes Vila vehla (Vv; 3.95 +/- 0.26 mg/g of DM) and El Harrach (EH; 3.99 +/- 0.19 mg/g of DM) showed after damage 22 and 32.8% TAC increases, respectively. Even sweet varieties, with very low alkaloid contents, Gungurru (Gu; 0.51 +/- 0.09 mg/g of DM) and Rumbo (Ru; 0.53 +/- 0.09 mg/g of DM) exhibited higher induced responses of 58.8 and 67.9%, respectively, and their final TAC values remained low, distinctly apart from those corresponding to bitter species. Moreover, minor components such as ammodendrine, reported to exhibit teratogenic potential, showed no significant changes in their relative abundances in response to biomass removal in these genotypes.