Better information makes for healthier horses,
Horseadvice.com is where equine science and horse sense intersect.

Discussion on Crown Vetch, Coronilla varia L.

Use the navigation bar above to access articles and more discussions on this topic.
Author Message
Top of pagePrevious messageNext messageBottom of page Link to this message

Alice MEYERS-PAULIN
Member
Username: 1907

Post Number: 2
Registered: 4-2002
Posted on Tuesday, May 30, 2006 - 12:12 pm:   Edit PostPrint Post

Can anyone tell me please if you have information or experience with crown vetch being poisonous to horses. We are in the process to plant crown vetch on the steep sides of our pastures where there is no possibility to mow. Now I have heard about this plant being poisonous to horses. Any suggestions ???
Top of pagePrevious messageNext messageBottom of page Link to this message

Holly Wood
Member
Username: Hwood

Post Number: 1205
Registered: 3-2001
Posted on Tuesday, May 30, 2006 - 12:30 pm:   Edit PostPrint Post

Hi, Alice,
I never had any trouble with purple vetch or crown vetch in my pastures in Vermont. I never heard that they were poisonous, but if you give your University Extension Service a call and ask them, I'm sure they can give you the information you need. Also, have you tried searching "CROWN VETCH" on google?
Top of pagePrevious messageNext messageBottom of page Link to this message

timothy miller
Member
Username: Tpmiller

Post Number: 26
Registered: 11-2003
Posted on Tuesday, May 30, 2006 - 12:32 pm:   Edit PostPrint Post

Have had horses and mules on pastures infested with crown vetch for 11 years, none touch it. Cattle love it, good source of protein.

Crown vetch is a vine that spreads fairly rapidly once started and is difficult to eradicate. Here in PA planted on roadsides, in 20 years has spread 100's of yards into pastures. For that reason, I'd look for something else to put on the bank or be prepared to mow it down regularly as it spreads.
Top of pagePrevious messageNext messageBottom of page Link to this message

Vicki Zaneis
Member
Username: Vickiann

Post Number: 230
Registered: 3-2005
Posted on Tuesday, May 30, 2006 - 3:52 pm:   Edit PostPrint Post

I've loaned my poisonous plant book for horse owners to a friend but I do recall "Vetch" being in there. Many horses will NOT eat certain poisonous plants but some will -- even seeking out strong tasting plants like lantana.
Top of pagePrevious messageNext messageBottom of page Link to this message

Vicki Zaneis
Member
Username: Vickiann

Post Number: 231
Registered: 3-2005
Posted on Tuesday, May 30, 2006 - 4:01 pm:   Edit PostPrint Post

Wikipedia says some species of Vetch are suitable for ruminant animals (cattle, goats, sheep,etc.) but NOT for animals having a single stomach (horses); including humans, due to toxin.
Top of pagePrevious messageNext messageBottom of page Link to this message

Leilani Clark
Member
Username: Leilani

Post Number: 130
Registered: 4-2000
Posted on Tuesday, May 30, 2006 - 4:22 pm:   Edit PostPrint Post

Crown Vetch, I believe, contains nitroglycosides which affects the nervous system in ruminants. Leilani
Top of pagePrevious messageNext messageBottom of page Link to this message

Julie Harrington
Member
Username: Bodie

Post Number: 12
Registered: 4-2002
Posted on Tuesday, May 30, 2006 - 10:51 pm:   Edit PostPrint Post

Leilani,
Correct on the nitroglycosides, but it affects the nervous system of non-ruminants. Ruminants are able to convert and detoxify it, but simple-stomached species cannot.
Julie
Top of pagePrevious messageNext messageBottom of page Link to this message

Leilani Clark
Member
Username: Leilani

Post Number: 131
Registered: 4-2000
Posted on Wednesday, May 31, 2006 - 12:11 am:   Edit PostPrint Post

Julie,

Mea culpa; forgot the 'non'. Leilani
Top of pagePrevious messageNext messageBottom of page Link to this message

Robert N. Oglesby DVM
Moderator
Username: Dro

Post Number: 15740
Registered: 1-1997
Posted on Wednesday, May 31, 2006 - 7:04 am:   Edit PostPrint Post

When you research Crown Vetch you get back recommendations for and against its use. Searching PubMed you don't find a case of poisoning. Considered its wide spread use (and the posts from above) it appears to be only of low toxicity but some references are adamant about it's toxicity. Oddly the actual cause of poisoning in horses seems confused as in this reference:

Crown Vetch
Coronilla varia - Fabaceae (Legume family)
Habitat
Crown vetch is frequently used as a drought-tolerant ornamental ground cover to help control erosion in the United States especially in the Midwest and Northeast.
Description
Crown vetch is a perennial herb with trailing or ascending, branching stems arising from a taproot. Leaves are alternate and pinnate with a terminal leaflet. The pealike flowers are produced from the leaf axils on a stalk 3 to 5 inches (7.5 to 12.5 cm) in length. Flower color varies from white to dark pink. Many brown, cylindrical seeds are produced in pods 1 to 2 inches (2.5 to 5 cm) in length.

Crown Vetch

Principal Toxin
Crown vetch contains nitroglycosides, the most toxic of which, coronarian is poisonous to horses and other nonruminants. Ruminants are not affected because they are able to convert the coronarian to 3-NPA that is readily detoxified in the rumen. Toxicity may be due to the development of methemoglobinemia and the inhibition of succinate dehydrogenase, an important enzyme necessary for energy metabolism. Crown vetch does not cause bloat in ruminants because it contains tannins that precipitate soluble proteins, which contribute to the rapid formation of a frothy foam in the rumen. Creeping indigo (Indigofera spicata), a legume introduced into southern Florida and Hawaii, also contains nitroglycosides that have caused poisoning in horses.
Clinical Signs
Nonruminants may show weight loss, poor growth rates, depression, ataxia, and posterior paralysis leading eventually to death of the animal.


Considering everything, I would not choose to use it in a pasture for horses.
DrO
Top of pagePrevious messageNext messageBottom of page Link to this message

Alice MEYERS-PAULIN
Member
Username: 1907

Post Number: 3
Registered: 4-2002
Posted on Wednesday, May 31, 2006 - 2:14 pm:   Edit PostPrint Post

To all responded: Thank you so much for your input, it was very informative. I guess we will look for an alternative since the pasture is occupied by youngsters year round; just don't want to take the risk. Thank you all very much again.
Top of pagePrevious messageNext messageBottom of page Link to this message

Cecelia L Bulkley
Member
Username: ceceb

Post Number: 14
Registered: 2-2004
Posted on Wednesday, Aug 1, 2007 - 5:10 am:   Edit PostPrint Post

Dr. O, My horse is in a pasture that is loaded with creeping indigo. I've fenced off the majority of the area infested and I'm trying to kill off the weed. There is still some patches so how much do they have to eat before it would make them sick. I'm using Roundup to kill it.

Thanks,Cece
Top of pagePrevious messageNext messageBottom of page Link to this message

Robert N. Oglesby DVM
Moderator
Username: dro

Post Number: 18952
Registered: 1-1997
Posted on Wednesday, Aug 1, 2007 - 6:45 am:   Edit PostPrint Post

Hello Cecelia,
There have been no studies on how toxic this plant is so I would do everything practical to avoid contact and if removing all contact difficult be sure there is always a palatable alternative forage available.
DrO
Post a Message to this Discussion
Posting
Instructions:
Full Service Members may post to this discussion and should address the orignial poster's concerns or other information posted here. New questions about your horse should be started in a new discussion. Use the navigation bar at the top of this page to return to the parent article and review the article and existing discussions. If your question remains unanswered "Start a New Discussion", the link is under the list of discussions at the bottom of the article.
Post:
Bold text Italics Underline Create a hyperlink Insert a clipart image

Username:
Password:
Options: Enable HTML code in message
Automatically activate URLs in message
Action:
Home Page | Todays Discussions | Search | Top of Page Administration
  http://www.horseadvice.com
is The Horseman's Advisor
Helping Thousands of Equestrians, Farriers, and Veterinarians Every Day
All rights reserved, © 2009
BBB Reliability Seal