North Dakota State University offers information for the care of livestock before, during and after floods.
Issues of Disease Control and Sanitation
If your fields or farm buildings have been flooded, take special precautions against flood-related accidents or diseases in poultry and livestock. Give animals extra care, particularly if they have been stranded by floodwater, and have been off regular feeding schedules. Keep fields clear of harmful debris, and clean buildings as soon as possible. In addition, watch for signs of flood-related diseases, such as lameness, fever, difficulty breathing, muscle contractions or swelling of shoulder, chest, back, neck or throat. Be prepared to contact a veterinarian if you spot trouble.
Following a flood there may be danger of infectious diseases in livestock, but unless serious outbreaks of infection have occurred recently, the situation should not be alarming. Observe these precautions:
Where large numbers of animals are assembled, watch for any indication of infectious diseases such as pneumonia, foot rot or leptospirosis. These diseases are more likely to occur where cattle are crowded on wet ground and where horn flies and houseflies are abundant.
Promptly report any sign of disease to a local, state or federal veterinarian.
Contact a veterinarian about vaccinating animals for immunity from flood-related diseases such as anthrax, blackleg and swine erysipelas.
Feed and Water
Provide clean, uncontaminated water.
Inspect feeds such as corn, wheat and hay. Do not feed flood-damaged or moldy hay unless it has been tested for mycotoxins, toxic substances produced by fungi.
Do not use any feed or forage that may have been contaminated by chemicals or pesticides.
Standing water may have ruined some pastures. Lack of adequate forage could force animals to eat poisonous plants. Remove fallen wild cherry limbs from pastures to prevent livestock poisoning.
Before restocking flooded pastures, remove debris, especially along fence lines and in corners. Livestock could be injured from pieces of barbed wire, sharp metal and trash.
Protecting Dairy Cows
Try to milk at regular times. It is better to lose the milk from one milking than to stress high producing cows.
If you must use a neighbor's milking parlor, try to keep the two herds separate.
If feed supplies are limited, give the largest portion of available feed to the highest producing cows and those recently fresh. This may be a good time to cull the herd.
Clean and sanitize milking parlor, dairy barn and equipment before returning to normal use.
Watch for signs of mastitis, which is likely to flare up if milking methods, time and equipment have been changed.
Clean out hog houses, barns and chicken houses. Spray buildings with a good disinfectant before animals occupy them again. Air buildings thoroughly to dry them out.
Remove debris from dairy barns. Scrub and disinfect walls, ceilings, floors, stanchions and other equipment.
Scrub the milk house and equipment with detergent and hot water. Sanitize equipment, walls, ceilings and floors with dairy sanitizer equipment.
Dispose of animal carcasses promptly. If there is no rendering company operating nearby, burn or bury carcasses deeply in a place approved by your local soil conservation office.
Mosquitoes and other pests may be abundant after a flood. They not only annoy animals, but some species carry disease. Spray animals with an insect repellent as recommended by your county agricultural agent.