Locoweed (Astragalus lentiginosus) poisoning in cattle and horses.

This research article explores the negative effects of locoweed (Astragalus lentiginosus) ingestion on Aberdeen-Angus cows and horses in Utah, leading to disruptive health issues such as abortions in cows and long-lasting damage to horses’ central nervous system.

Study Context and Methodology

• This study was conducted amidst Aberdeen-Angus cows and horses that consumed locoweed during a rotational grazing regime in Utah.
• The locoweed became the only green feed available for these animals at the time, leading to their inevitable consumption of the toxic plant.
• Observational data on the symptoms and severity of locoweed poisoning in both Aberdeen-Angus cows and horses were collected. In addition, Hereford cattle, which had other green forage available and thus did not consume significant amounts of locoweed, were observed for comparative purposes.

Findings in Aberdeen-Angus Cows

• Of the 70 Aberdeen-Angus cows that consumed locoweed, a vast majority reportedly aborted.
• While all the cattle demonstrated signs of locoweed poisoning, they all recovered once they were removed from the field containing locoweed.

Findings in Horses

• Besides the cows, 12 horses that consumed locoweed showed symptoms of poisoning.
• Even though these horses appeared to recover, signs of lasting damage to the central nervous system remained.

Comparative Observations with Hereford Cattle

• Hereford cattle, which were exposed to a similar quantity of locoweed, did not display any signs of poisoning.
• This is attributed to the fact that the Hereford cattle had other green vegetation available to feed upon, suppressing their need to consume the toxic locoweed.

Implications of the Research

• The study provides clear evidence of the detrimental impact of locoweed on cattle and horses, particularly if it is the only source of green feed available.
• The results underline the importance of providing a varied and non-toxic food source for grazing animals to prevent such health issues.
• The contrast in the health outcomes between the Aberdeen-Angus cows, horses, and the Hereford cattle underscores the role of dietary diversity in preventing toxic plant ingestion and its aftermath.

To sum up, the research highlights the severe health consequences of locoweed consumption in grazing livestock and underscores the importance of maintaining dietary variety to prevent such outcomes.