Blue-green algae toxicosis in five dairy cows

Area of Science:

• Veterinary Medicine
• Toxicology
• Environmental Health

Background:

• Blue-green algae (Cyanobacteria) blooms, particularly Microcystis aeruginosa, can produce toxins harmful to livestock.
• Blue-green algae toxicosis is often perceived as a rare, rapidly fatal condition in animals.
• Limited diagnostic tools contribute to underdiagnosis of this toxicosis.

Purpose of the Study:

• To report a case of clinical blue-green algae toxicosis in Holstein cows.
• To investigate the potential for non-lethal outcomes and effective treatment of this condition.
• To highlight the possibility of blue-green algae toxicosis being more prevalent than commonly recognized.

Main Methods:

• Observation of clinical signs in five Holstein cows presenting with ataxia, tremors, recumbency, and bloody diarrhea.
• Identification of Microcystis aeruginosa in the water source used by the affected cows.
• Treatment protocol including activated charcoal, procaine penicillin, glucose, and calcium/magnesium gluconate.

Main Results:

• All five affected Holstein cows recovered within ten days of treatment.
• The clinical syndrome resolved following administration of activated charcoal and supportive care.
• The water source was found to contain a near-pure culture of toxic Microcystis aeruginosa.

Conclusions:

• Blue-green algae toxicosis, specifically from Microcystis aeruginosa, may present with treatable, non-lethal clinical signs.
• This toxicosis might be more common in cattle than previously assumed, despite diagnostic challenges.
• Effective supportive care can lead to complete recovery in affected animals.