Health

Current Status of New World Screwworm (NWS) Infestations in the U.S.

Dr. Gustavo M. Schuenemann, Department of Veterinary Preventive Medicine, The Ohio State University

The NWS has been largely eradicated in the United States for over 50 years, but a current outbreak in Central America and Mexico is moving closer to the U.S. On August 18, 2025, the Secretary of Health and Human Services issued the emergency declaration after determining that NWS “has a significant potential to affect national security or the health and security of United States citizens living abroad and that involves New World Screwworm.” This emergency declaration allows veterinarians to use certain treatments under extra-label use provisions, to help control potential infestations.

What is NWS?
It is a parasitic fly (Cochliomyia hominivorax) that lays eggs in and on open wounds and mucous membranes of warm-blooded animals. When larvae hatch (maggot), they burrow into the flesh of these animals and eat healthy living tissue causing the myiasis. This infestation is Continue reading Current Status of New World Screwworm (NWS) Infestations in the U.S. →

Sheep, Goats, and Worms – Oh My!

Dr. Emily Nogay, DVM, Faculty, OSU Large Animal Services
(Previously published online with Ohio’s Country Journal and Ohio Ag Net: August, 10, 2025)

Skinny goat? Worms. Diarrhea? Worms. Pale eyelids? Worms. Gastrointestinal parasites often take the blame for any small ruminant that is looking ill. Many times, they are responsible; however, it is important to remember that parasites are a natural part of life, especially for animals that eat off the ground.

Although sheep and goats are susceptible to many types of gastrointestinal parasites, there is one that takes the cake – the barber pole worm or Haemonchus contortus. This worm lives inside the true stomach (abomasum) and attaches to the stomach lining to feed on the blood of the animal. This worm is common in all sheep and goats, and unfortunately, it is nearly impossible to eliminate. Large enough worm burdens can cause weight loss, diarrhea, anemia, localized edema (also known as “bottle jaw”), and subsequent death. Animals become Continue reading Sheep, Goats, and Worms – Oh My! →

Guide for Control of External Parasites of Sheep and Goats

Marcy Ward, Extension Livestock Specialist, New Mexico State University
(Previously published with New Mexico State University: Guide B-112:Guide for Control of External Parasites of Sheep and Goats)

(Image Source: AWI – Australian Wool Innovation Limited)

External parasites can greatly impact wool quality in sheep, milk production in sheep and goats, and overall animal health. Therefore it is very important to include a parasite control program in a herd health management plan. Increased regulations have removed many traditional pest control products from the market. With technological advancements, however, effective systemic parasite control is still possible.

With the use of any drug or chemical, following label instruction is imperative for getting the proper results while reducing the risk of
product resistance.

Fleeceworms (Wool Maggots)
Even in well-managed flocks, Continue reading Guide for Control of External Parasites of Sheep and Goats →

Biosecurity for Bringing Home New Sheep and Goats

Carolyn Ihde, Agriculture Educator for Crawford and Richland Counties, University of Wisconsin-Madison
(Previously published online with: Livestock Division of Extension, University of Madison-Wisconsin)

(Image Source: Ohio Country Journal and Ohio Ag Net)

With much of Ohio deep into fair season, many fair families are transporting livestock all over the state. Of course, getting your stock home safely and in a timely manner in this heat should be your top priority, but ensuring that you are taking the proper measures to keep the rest of your operation healthy and safe at home should be just as important! This week, Carolyn Ihde from the University of Wisconsin-Madison highlights those important steps and considerations as it relates to on-farm biosecurity. Enjoy!

Purchasing new sheep or goats is exciting. Acquiring new animals can mean increased production, increased animal longevity, or improvement in a variety of characteristics the existing flock or herd needs. However, as exciting as it may be, biosecurity steps must be in place before

Continue reading Biosecurity for Bringing Home New Sheep and Goats →

Help! I have Hemp Dogbane

Christine Gelley, OSU Extension Educator ANR, Noble County

Over the past couple of weeks, we’ve had several inquiries about hemp dogbane concerns and requests for help with keeping it under control in agricultural systems.

Both hemp dogbane and milkweed are easy to find this time of year and are often growing in the same habitat, which can be anywhere from roadsides, creek edges, open fields, forest edges, and flower beds. These two plants are related but have some distinct differences that can help landowners identify them and implement control measures when needed.

Similarities between the two plants include that they have creeping roots; leaves that appear on opposite sides of the stem; and they produce a milky sap. Differences include that young milkweed leaves have fine hairs and hemp dogbane are nearly hairless; milkweed stems are Continue reading Help! I have Hemp Dogbane →

Fly Control in Livestock for Summer

Dr. Ted Wiseman, OSU Extension ANR Educator, Perry County

(Image Source: Intermountain Farmers Association (IFA))

As summer temperatures rise, so does the pressure from biting and nuisance flies on livestock operations. According to university research, fly infestations cost U.S. producers an estimated $700 million to $1 billion annually in lost performance. With today’s strong livestock markets, minimizing these losses through effective fly control is more important than ever.

Understanding the Impact of Flies on Livestock
Flies reduce productivity by interfering with feeding, causing stress, and transmitting disease. The primary culprits include: Continue reading Fly Control in Livestock for Summer →

An Update on Ticks and Tick-borne Disease in Ohio: Plus the Buckeye Tick Test Lab

Dr. Tim McDermott, OSU Extension Educator ANR, Franklin County

It seems in Ohio it is never too early to start scouting animals for ticks. While we commonly think of summer as tick season, we actually see tick activity and positive detections of tick-borne disease all 12 months of the year in Ohio. One of the ticks of the biggest concern impacting livestock, especially cattle, in Ohio is the invasive Longhorned Tick(LHT). This tick was first discovered in Ohio on a dog in Gallia County in 2020 and has rapidly increased its range in Ohio since then. As of the beginning of 2024 we had positively identified LHT in 11 counties in Ohio including Franklin, Delaware, Ross, Gallia, Vinton, Jackson, Athens, Morgan, Monroe, Belmont, and Guernsey county. Since that point we have added Pike, Lawrence, Noble, Coshocton, Wayne, Muskingum, Washington, and Licking bringing our total up to 19 affected counties. We anticipate adding to that list in 2025.

The Longhorned tick can be a Continue reading An Update on Ticks and Tick-borne Disease in Ohio: Plus the Buckeye Tick Test Lab →