Are Parasites a Limiting Factor in your Operation?

Bill Fosher, Granite State Graziers coordinator and New Hampshire sheep producer
(Previously published in On Pasture: March 1, 2021)

The parasites that infest sheep can be an enormous drag on sheep production. Year in and year out, they probably cause more death and disease in some producers’ lamb crops than any other single factor, including predators.

The days when the answer to parasite management was to drench all the sheep every month are behind us. Parasites have started to evolve resistance to various classes of de-wormers. The problem with chemical resistance is so pronounced in some parts of the Southeast US that there are farms where no de-wormers work anymore, and there’s at least some degree of chemical resistance nearly every place where worms are a problem.

The first step in knowing how to manage parasites in your own farm is to know what’s going on in your flock’s guts and in the environment they inhabit. The second step is to know what environmental factors play into parasite reproduction and infectivity. In the final analysis, the answer for how to Continue reading

The Role of Fecal Egg Counting in Sheep/Goat Health

Susan Schoenian, Sheep & Goat Specialist, University of Maryland Small Ruminant Extension Program
(Previously published on the American Consortium for Small Ruminant Parasite Control: August 2020)

Although parasite burdens are low in many Ohio systems in the current moment, it is never too early to consider your 2021 parasite management plan. Many producers tend to treat for parasitic infection blindly and routinely, regardless of the true needs of their flocks or herds. For those interested in understanding the importance and implementation of fecal egg counting in your operation when it comes to parasite management be sure to take a peek at this quick read from Susan Schoenian.

A fecal egg count (FEC) is a quantitative measure of how many worm eggs a sheep/goat is passing in each gram of its manure. You get a number like 1000 EPG (eggs per gram of feces).

Fecal egg counts are performed by veterinarians, state diagnostic labs, and independent laboratories. You should only be willing to Continue reading

Prevent Parasites Through Grazing Management

Melanie Barkley, Livestock Extension Educator, Penn State Extension
(previously published with Penn State Extension: May 31, 2017)

Grazing management and genetic selection can help your flock minimize the impact of parasites.

Parasites continue to plague many sheep and goat producers throughout the grazing season. Internal parasites decrease growth rates and in high levels can even cause death. However, sheep and goat producers can follow several practices to minimize the impacts to their flock or herd. These practices center on grazing management, but can also include genetic selection principles.

Livestock pass internal parasite eggs in their manure. These eggs then hatch and go through several larval stages until they reach an infective stage. This can take as little as six days to go from egg to infective stage. Therefore, producers can use grazing rotations to Continue reading

An In-Depth Look at Ivermectin

Susan Schoenian, Sheep & Goat Specialist, University of Maryland Small Ruminant Extension Program
(Previously published in Wild and Wooly – Spring 2020)

(Image Source: Valley Vet Supply)

Recently, several media outlets reported the success of an in vitro study conducted in Australia regarding the antiviral effects of ivermectin on the virus that causes COVID-19. An in vitro study is performed outside the living organism, such as in a petri dish; where- as, an in vivo study is conducted in a living organism. A treatment may work in vitro but not in vivo or it may work in both or neither.

Ivermectin has shown in vitro activity against the zika virus, but its effect Continue reading

Best Management Practices for De-worming Sheep and Goats

With warmer weather projected in the near forecast and pastures beginning to become full and lush, many producers have or will soon be turning their stock out onto pasture. It is critically important that we monitor the health and well-being of our animals on a daily basis. For those that may need treatment due to parasitic infection, it is important to understand which de-worming products to use at the appropriate time and how to correctly incorporate them into your management system.

Parasite Management Starts with Genetics

Gail Keck
(Previously published in Ohio Farmer: February 24, 2020)

Ohio producer uses data to increase his sheep flock’s resistance to internal parasites.

For sheep producers with flocks on pasture, controlling internal parasites can be expensive and time-consuming, but the cost of not controlling the parasites can be even greater, in reduced performance and death losses. While it won’t eliminate the need to monitor and deworm entirely, building a flock with greater genetic resistance can help reduce losses and treatment expenses.

John Anderson, who raises Polypay sheep seedstock near Shreve,in Wayne County, Ohio, has been selectively breeding for parasite resistance for 10 years, and he’s seeing the benefits in his own flock and in the breeding stock he sells.

Continue reading

Larval Survival of Barber’s Pole Worm

Wormboss
(Previously published on Wormboss, Tests and Tools, Management Tools, Grazing Management)

(Image Source: Deb Maxwell)

Problem:
Many producers are unaware how long is required to prepare low worm-risk paddocks, although surveys show most are in favor of using them.

Solution:
Understanding the few conditions under which worm larvae will die is vital in creating low worm-risk paddocks.

Benefit:
Knowing the ‘required time’ for your property to create low worm-risk paddocks.

Under what conditions do worm larvae die?
A common misconception, based on having fewer worm issues in winter, is that frosts kill worm larvae on the paddock. This is a myth.

Continue reading

Using Refugia to Manage Parasites

Veterinary Practice New
(Previously published on the American Consortium for Small Ruminant Parasite Control web page, January 3, 2020)

With 2020 underway, the U.S. Food and Drug Administration (FDA) says it is continuing its ongoing effort to address issues related to antiparasitic resistance in livestock and horses across the country. Among these efforts are two videos on the subject, directed at large animal producers and owners.

Continue reading

Ag-note: Parasite Focus – Haemonchus Contortus

Kirsten McCollough, Kourtney Sprague, Jamie Summers, Kristi Lampton, and Hannah Whitaker, OSU Animal Science Undergraduate Students
Brady Campbell, Program Coordinator, OSU Sheep Team

Parasite Focus – Haemonchus Contortus
** Follow the link above to view the Ag-note.

To kick off the next series of Ag-notes compiled by The Ohio State University’s AS 4004 class of 2019, I found it appropriate to hit a timely topic, parasites, especially with the previously wet and now hot and humid environmental conditions that many livestock and their producers are experiencing. Therefore, Animal Sciences students Kirsten McCollough, Kourtney Sprague, Jamie Summers, Kristi Lampton, and Hannah Whitaker chose to focus on a specific parasite that is continually becoming more difficult to manage for small ruminant producers raising sheep and goats on pasture – Haemonchus contortus. Continue reading

Preparing Low Worm-risk Paddocks

Wormboss
(Previously published on Wormboss, Tests and Tools, Management Tools, Sheep)

Problem: Continuous re-contamination of the paddocks with worm eggs that develop to larvae is a major cause of ongoing worm problems for sheep or goats.

Solution: Preparing low worm-risk paddocks to prevent animals from becoming heavily infected with worms is a key strategy in effective and profitable worm control.

Benefit: Low worm-risk paddocks for key classes of stock at particular times of the year reduce both production loss and the need for chemical (de-worming) intervention. In turn, fewer [treatments] result in Continue reading

Supplementation of Pasture-Raised Lambs Increases Animal Performance and Health

Brady Campbell, Program Coordinator, OSU Sheep Team

To capitalize on the niche market of grass-fed lamb products, have you ever considered placing a group of feeder lambs on pasture? The utilization of pastureland and the financial return from grass-fed products makes this type of production system profitable. However, grass-fed lamb production does not come without challenges. According to the USDA, in order for a product to be labeled as grass-fed, the animal must be fed solely forages, with the exclusion of its mother’s milk prior to weaning. From a production standpoint, this can be a difficult as research has shown that lambs finished on pasture take a longer period of time when compared to their counterparts fed grain. Lambs on pasture also face the challenge of parasitic infection. In an effort to decrease the effects of parasites and increase lamb body weight gain on pasture, producers may choose to supplement lambs while on pasture. However, supplementation of grain or grain by-products is not permitted by Continue reading

Grazing Management – Reducing the Use of Anthelmintics

Wormboss
(Previously published on Wormboss, Tests and Tools, Sheep)

Problem:
Continually high worm burdens in your grazing animals resulting in the need to drench more frequently.

Solution:
Managing the frequency and intensity with which livestock graze pasture reduces the number of infective larvae ingested from the pasture each day.

Benefit:
Effective grazing management will reduce the exposure of vulnerable sheep to larvae on pasture and the need for chemical (drench) intervention and at the same time provide nutrition to allow sheep to better deal with parasites. Continue reading