Exam 2 Flashcards
What were the three main goals of the paper according to the author?
- describe how weed invasions degrade biological communities and displace native species
- outline how wildland managers approach weed control
- Present examples of difficult and unusual weed problems wildland managers face
What exactly is a weed? Invasive species?
- Native and non-native species, don’t want it or see value in it, doesn’t need to be invasive; why do we care? Disrupt ecosystem function (change nutrient cycling, water filtration, ecosystem services)
- invasive species are a species that can move into an area and become dominant, native or nonnative, no natural enemies; can be plant, animal, virus, insect, microbes, etc.
How do plant invasions affect wildland?
- alteration of ecosystem processes
- displacement of native species without otherwise changing the ecosystem structure
- support of nonnative animals, fungi, or microbes
- Hybridization of nonnative species with native species; alter gene pool
Consider the examples given. Why do we care about invasive species?
- alter ecosystem processes such as a nutrient cycling, intensity and frequency of fire, hydrological cycles, sediment deposition, and erosion
What does it mean to use an adaptive management strategy>
- make goals of preserve, identify weeds, implement control
What are the downsides to controlling weeds?
- expensive
- collateral damage
- subjective
How can biodiversity help up?
- creates a more sustainable ecosystem
- provides food for pollinators
- natural selection
- nutrient cycling, organic matter added to soils
- oxygenation, filtration of water, top soil
- Promote wildlife biodiversity
- Improve forage and crop yields
- Might decrease invasive species
How can we manage biodiversity?
- reduce poisoning
- decrease plant disease/increase resistance (genetic diversity)
- bank stabilization w/increase plants
- increase primary production of natives
- reduce fire impacts
- improve pest control in crops
Nightshade plant
solanum dulcamara
Nightshade plant toxin
metoclopramol
Describe a nightshade plant
dark green leaves, star-shaped purple flowers w/backward pointing petals, large yellow stamen
What are the symptoms of nightshade poisoning?
tremors, vomiting, ataxia, depression, diarrhea
Protoanemonins include what spp.?
- ranunculus family
- blister buttercup (ranunculus sceleratus)
- burr buttercup (ceratocephala testiculata)
- clematus spp.
- acteorulora
- baneberry (actaea rubra)
How many spp. are in the nighshade poisoning?
2300
What kind of toxin is nightshade poisoning?
Steroidal glycoalkaloid
- Solamine
- Hyoscine (Zombie Drug)
- Hyocyamine (Atropine)
- ALSO
- nicotine (toxic alkaloid)
- vitamin D like toxins
What is nightshade poisonings mechanism of action?
- blocks action of cholinesterase
- accumulation of acetylcholine
- inhibits parasympathetic nervous system
What are the symptoms of nightshade poisoning?
- initial CNS excitation
- increased nerve impulses and tachycardia
- Subsequent CNS depression
- Decreased heart rate
- Muscle weakness
- Dilated pupils
- Stomach rupture and paralysis of GI tract
How can you treat nightshade poisoning?
- physostigmine
- symptomatic treatment
- activated charcoal
- absorbent
When are plants that cause diarrhea usually eaten?
drought
What plants can cause diarrhea?
- leafyspurge (eurphorbia esulas)
- western yarrow (achilea millefolium)
What toxins might cause diarrhea?
- glycoalkaloids
- saponins
- turpenes
- lactones
- more ;)
Diarrhea causing plants effect what?
Cattle and horses are most effected, but sheep can eat about 40% of diet
What are the symptoms of spurge and yarrow?
spurge= excessive salivation
yarrow= colic and photosynsetivity
What toxins are in lectin poisoning?
- highly toxic
- glycoproteins
- concentrated in seeds
- present throughout the plant
- Ricin
- castor bean really pretty
- robinin
- black locust
What is the toxicity of lectin poisoning?
- horses are most susceptible
- all livestock can be affected
- contaminated feed/grain
- 40-60 beans for fatal poisoning
What is lectin poisonings mechanism?
- Endocytosis
- passes through organelles to ER
- depurinates ribosomes at a rate of 1500 ribosomes per minute
- cell death
What are the symptoms of lectin poisoning?
- hours-days after digestion
- ricin- violent vomitting, bloody diarrhea
- robinin- diarrhea, anorexia, posterior paralysis; postmartem= GI tract lesions
How do you diagnose and treat lectin poisoning?
- Diagnose- observe eating or seeds or castor bean cake
- Treat- remove seeds, activated chaarcoal, IV fluids
What are some spp. that cause lectin poisoning?
- Castor bean (ricinus communis)
- black locust (roinia pseudoacia)
- new mexican black locust (robinia neomexicana)
- european privet (ligustrum vulgare)
How are protoanemonin created?
ranuculin interacts with plant enzymes creating protanemonins
Photosensitivity defined is what?
severe dermatitis
created by UV reactions with plant pigments
What are photosensitive toxins?
- hypericin
- fagopyrin
- furanocoumarins
What is the mechanism of photosensitivity?
- absorbed into blood
- exposed to UV in skin
- breaks down into toxin compounds or free radicals
What are some plants ass. with photosensitivity?
- st. johns wort (hypericum perforatum)
- buckwheat (fagopyrum esculentum)
- spring parsley (cymopterus watsonii)
What is secondary photosensitivity a symptom of?
Liver disease
Phylloerythrin (byproduct of chlorophyll)
Secondary photosensitzation is associated with what plants?
horsebrush (tetradymia spp.)
tansy mustard (duscurania pinnata)
Secondary photosensitivity causes liver issues. Describe them and why it happens.
- pyroliziding alkaloid poisoning
- pigs > cattle, horses > sheep
- toxicity
- sheep can eat 20 x more
- pregnant, malnourished with increase toxicity
- cumulative
What is the mechanism of secondary photosensitivity?
- pyrrolizidine alkaloids go to the liver
- the liver transforms it via bioactivation to toxic pyrrole
- toxic pyrrole inhibits mitosis, preventing the formation of new hepaatocytes
PA hgih dose?
PA lose dose?
- PA High Does: Hepatocellular necrosis
- PA Low Dose: less sever necrosis, fibroids
- Fibroids in the kidney
- Pulamonary hypertension
- Right heart failure
- *passed through milk too
What are the plants associated with secondary photosensitization that we need to memorize?
- Fiddle neck (amsinckia intermedia)
- Groundsel/Tansy ragwort (senecio spp.)
- Houndstongue (cynoglossum officinate)
Bilary occlusive photosynsetization mechanism of action is?
- Inflammation obstructs bile duct
- Bile can’t be excreted
- Phylloerythrin build up
What are some associated plants with secondary photosensitization?
- Puncture vine (tribulus terrestris)
- Lantana (lantana camara)
- Alsike clover
- irreversible liver damage, neurological distrubance
- Trifoliosis: photosensitivity w/o apparent liver disease in horses
- Mycotoxins (aflatoxins)
- aspergillus and penicillium spp.
- moldy hay, straw, grains, silage
- hepatoxic- liver damage
- specific to cattle
- rumen or liver metabolism possibly
- aspergillus and penicillium spp.
- Blue green algae poisoning
- eutrophication
- algae blooms with high temperatures
- toxins released as cells die
- Severe poisoning in livestock
- primary neurotoxic effects
- sudden death
- Liver failure and secondary photosensitizaiton
What are the clinical signs of photosensitization? Hb secondary photosensitization?
- primary
- photophobia
- swelling and redness of non-pigmented skin
- secondary bacterial infection
- Secondary/PA poisoning
- weight loss
- abnormal neurological signs
- jaudice
How do you treat primary photosensitization? PA poisoning? Biliary occlusive?
- primary
- shelter from sun
- remove from plant
- clean affected skin
- treat secondary bacterial infection
- PA poisoning
- many proposed, few effective
- liver damage is irreversible
- Biliary occlusive
- recovery possible if toxicity hasn’t persisted very long
How do you control plants that cause photosensitization?
- eradication
- selective removal with herbicide
- biocontrol (St. John’s wort)
- sheep
How can you tell the difference between primary and secondary photosensitization? Between causes of secondary??
- remove from the plant- Does it help?
- No? - Liver biopsy
- difference between secondary types
- biliary occlusive if caught early can be treated and recovery is possible
- History of possible exposure to plant- can be difficult because could have been months ago
- difference between secondary types
Teratogens
Birth defects
What are the requirements of teratogens?
- cross placenta easily
- right species
- high enough concentration
- right gestational time
What ar ethe effects of teratogens?
- embryonic death
- abortion
- fetal abnormalities
- male infertility (spermatogenesis)
- female infertility (indirect)
What are some plants that are teratogens?
Milk vetches and locoweeds
What are milk vetch and locoweeds toxin?
- milk vetch (astragalus) and locoweed (oxytropis) have swainsonine
- indolizidine alkaloid
Which species are most effected by milk vetch or locoweed?
cattle < sheep < horses
with chronic locoweed poisoning
Causes enlarged heart/thyroid gland (sheep 60-90th day of gestation)
What are the symptoms of teratogen poisoning?
- abortion- anytime, secondary infection
- infertility- male, decreases sperm production, temporary 60-90 days
- fetal deformities- twisted limbs, abnormal bone development
How do you test for teratogen poisoning post mortem?
difficult to catch unless you test blood serum w/in two days of poisoning
Protoanemonin/Saponin species include
- Blister buttercup (ranunculus sceleratus)
- Bur buttercup (ceratocephala testiculata)
- Baneberry (actaea rubra)
Nightshade poisoning species include
- sacred moonflower (datura wrightii)
- black henbane (hyoscyamus niger)
- black nightshade (solanum nigrum)
- bitter nightshade (solanum dulcamara)
Vomiting can be caused by which species
- leafy spurge (euphorbia esula)
- western yarrow (achillea millefolium)
Lectin poisoning includes which species
- castor bean (ricinus communis)
- black locust (robinia pseudoacacia)
Primary photosensitization species include
- St. John’s Wort (hypericum perforatum)
- buckwheat (fagopyrum esculentum)
- spring parsley (cymopterus watsonii)
Secondary photosensitization species includes
- horsebrush (tetradymia spp.)
- tansy mustard (descurainia pinnata)
Pyrrolizidine alkaloids include which species
- Fiddleneck (amsinckia intermedia)
- Groundsel, tansy ragwort (senecio spp.)
- Hound’s tongue (cynoglossum officinale)
Biliary occlusive species include
- puncture vine (tribulus terrestris)
- lantana (lantana camara)
Alsike clover poisoning species include
- alsike clover (trifolium hybridum)
Congenital defects and reproductive failure can be caused by which species
- milk vetches (astragalus spp)
- locoweeds (oxytropis spp.)
- lupine (lupinus spp.)
- western false helleborne (veratrum californicum)
- broom snakeweed (gutierrezia sarothae)
- ponderosa pine (pinus ponderosa)
Lupine toxin is?
anagyrine
Quinolizidine alkaloid
Lupine toxicity affects cattle how?
- crooked calf disease
- 0.5-1.0 kg/day 40-70 of gestation
- limb deformity
- vertebral column malformation
- cleft palate
Lupine toxicity affects sheep how?
- acute fatal neurological disease
- head pressing
- lupinosis
- mycotoxin syndrome –> caused by mole that can grow on lupine
- severe liver/kidney/muscle disease
- mostly in sheep, grazing pods, stalks, stubble
Poison hemlocks toxin is??
coniine
alkaloid
Poison hemlock toxicity affects which species at what dose?
most toxic to cattle and pigs
sublethal dose, 50-70th day of gestation= crooked calf disease
How do you diagnose poison hemlock toxicity?
presumptive- plant presence in feeding area
Western false hellebore’s toxin is??
cyclopamine
classical teratogen
Western false hellebore toxicity causes what?
- Mostly sheep
- Cyclopia and facial deformities 14th day of gestation
- 30-35th day- shortened legs, completely or partially absent trachea
- Acute toxicity= vomiting, rapid heartrate, muscle tremors
What is the mechanism of western false hellebore?
disrupts the sonic hedgehog signaling pathway
What is the treatment of western false hellebore?
No antidote
symptomatic
Broom snakeweed’s toxin is?
saponins potentially
What are the clinical signs of broom snakeweed poisoning?
- Weight loss
- Jaundice
- Abortion
- Retention of placenta
Ponderosa pines toxin is?
isocupressic acid
also found in junipers
in needles, branch tips, and bark
Ponderosa pine toxicity causes?
- Abortion in cattle/bison
- Last trimester: ~2.5 kg/day for 3 days
- Premature birth/abortion occurs with in 2-21 days
What are the clinical signs of pine needle abortion?
- Edema of the vulva and udder
- Mucoid vaginal discharge
- Difficult labor
- Retention of placenta
- Secondary uterine infection
- Little to no colostrum
- Post mortem
- septic necrosis of uterus and placenta
Phytoestrogens can cause what? An example of a phytoestrogen is?
- Lowered fertility
- Cystic ovaries
- Atypical estrous cycles
- Ex. Red Clover
What is the cause of photosensitivity?
Absorption of photdynamic pigments
What can sheep eat as 40% of their diet, but cattle and horses are most effected by?
Diarrhea causing plants such as leafy spurge and western yarrow