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 →
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 →
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.
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.
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.
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 →
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 →
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 →
Continually high worm burdens in your grazing animals resulting in the need to drench more frequently.
Managing the frequency and intensity with which livestock graze pasture reduces the number of infective larvae ingested from the pasture each day.
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 →
(Image Source: American Consortium for Small Ruminant Parasite Control)
There now is very strong evidence that using combination treatment is the best method for using de-wormers and should be instituted on all farms immediately.
Resistance to de-wormers is a fact of life, and the situation has worsened greatly in recent years. Surveys indicate that most farms have worms resistant to at least two of the three major groups of de-wormers. Many have resistance to all three groups, and some farms now have resistance to all available de-wormers. But, having worms in your animals that are resistant to de-wormers does not mean that all the worms are resistant. For instance, when all the commonly used de-wormers were first introduced, their efficacy was > 99%. Once efficacy falls below Continue reading →
If you recall the article (Understanding Parasites on Pasture) from last week, we discussed the parasite life cycle and factors that affect overall survivability and of parasites on pasture. As promised, this week we will dive into a list of parasite management practices that producers have available in order to protect their herds and flocks from the losses associated with parasitic infection. With this being said, I’d like to first start with why previous recommendations that relied heavily on the use of de-worming (anthelmintic) products as a means of controlling parasites is no longer a viable option.
In short, because of the continual use of anthelmintic products, the livestock industry is being faced with Continue reading →
Image of an adult Haemonchus parasite recovered from the abomasum of a lamb
Recently, I had a sheep producer ask me, “when do I need to start thinking about parasites on my pastures?” This is a great question and certainly a valid concern as livestock are making their way to pastures this spring.
Now I know what some of you are thinking, “I don’t have issues with parasites. If I did, my sheep would be showing clinical signs of disease such as decreased appetite, decreased activity, or even death.” However, this is a common mistake that we as producers make too often. Typically, clinical signs of parasitic infection are only noticed when the cases become severe. According to Dr. Thomas Craig, DVM, PhD, DACVM, most losses associated with parasitic infection are Continue reading →
We are happy to announce that the first shipment of BioWorma® and Livamol® with BioWorma® has now been received and cleared meaning we are now open for business in the U.S. with our first official distributor being Premier 1 Supplies, located in Iowa. We expect to add a number of distributors/suppliers shortly.
We are actively looking for farm re-sellers (Livamol with BioWorma®) and veterinarians (BioWorma®) to supply and support BioWorma®. For further information, please contact firstname.lastname@example.org. Continue reading →
Nematode-trapping fungi have demonstrated potential as a biological control agent against the immature (larval) stages of gastrointestinal nematodes (worms) in livestock feces under both experimental and natural conditions. These fungi are normal soil inhabitants throughout the world where they feed on a variety of non-parasitic soil worms.
Of the various fungi tested, Duddingtonia flagrans spores have been shown to survive passage through the gastrointestinal tract of ruminants. After defecation, the spores Continue reading →
Susan Schoenian, Sheep & Goat Specialist, University of Maryland Small Ruminant Extension Program
(Previously published on the Maryland Small Ruminant Page)
Coccidiosis: deadly scourge of lambs and kids
(Image Source: Susan Schoenian, Maryland Small Ruminant Page)
Coccidiosis is a parasitic disease affecting a variety of animals, especially mammals and birds. The causative organism is a microscopic, spore-forming, single-cell protozoa called coccidia. Coccidia are from the same class of organisms (sporozoa) that cause malaria. Coccidia are sub-classified into many genera. In sheep and goats, coccidiosis is caused by the genus Eimeria .
BioWorma is the one of the latest products developed in the livestock sector to be used as an additional management tool to control for internal parasites. At this time, BioWorma has been registered by International Animal Health Products Pty Ltd in Australia, New Zealand, and the United States. This product is said to become available to producers in AU and NZ by early July, but as for the US, BioWorma must first receive EPA approval. Upon approval, regulation of use and distribution will be established by each state. Until then, gathering a better understanding of the product itself and how it can be implemented on-farm will be key to its success here in the US.
The sun is out, the grass is growing and livestock in Ohio are out on pasture contentedly grazing. There is something special about the relationship between animals and pasture on a farm but there are challenges as well, including parasites.
“Worldwide, producers are losing billions of dollars to parasites through production losses and actual animal losses. They are more of an issue in the Eastern U.S. because our grazing areas are more concentrated than in the West. Issues with parasites increase this time of year when temperatures are 50 to 104 degrees F. Beyond this range, their survivability decreases significantly,” said Brady Campbell, program coordinator of the Ohio State University sheep team. “When it is hot, humid, and wet they thrive. Now everything is out on pasture and when it is wet and dewy it is a problem. Dew is Continue reading →
Michelle Arnold, DVM (Ruminant Extension Veterinarian, UKVDL), University of Kentucky
Although this piece is written from a Beef cattle perspective, it covers an extremely timely and important topic. As you read this article, think about how this may apply to you in your operation and what management strategies you can implement in order to prevent production losses associated with parasitic infection.
A “non-renewable” resource is a resource with economic value that cannot be readily replaced on a level equal to its consumption. Petroleum and coal are two familiar examples of valuable non-renewable products used daily, but known to exist in limited supply, and formation of new product takes billions of years. De-wormers, on the other hand, are products that can be purchased from almost any farm or veterinary supply store and online. There are many different kinds, fairly inexpensive, and seemingly effective at Continue reading →
Cattle, horses, sheep, and goats are all susceptible to internal parasites, which can be devastating to producers economically.
“Many times, the effects are subclinical and may go unnoticed, but severe infestations can cause disease and death,” says Adam Speir, a county extension agent with the University of Georgia’s forage extension team.
Speir notes that the effects of infestations can come in many forms, with the most common being reduced milk production, reduced weaning weights, delayed puberty, lower Continue reading →
At what age do you wean your lambs? This is a question that I have asked producers many times. I have heard ages ranging from 35-130 days of age with the most common answer being 60 days of age. This is the most common weaning age for producers in the eastern United States. When I ask producers why they wean their lambs at 60 days of age or younger, most respond with “that’s the way we have always done it here on the farm, so why change now?”
From a researcher’s perspective, this is not a valid answer. Weaning before the natural weaning age (between 100-180 days of age depending upon sheep breed) is stressful. Weaning stress can lead to decreases in animal performance as demonstrated by decreased weight gain. Weaning stress can also result in decreased animal health as shown by decreases in immune system function that can lead to an increased susceptibility to disease and infection. However, if we were Continue reading →
Since the mid-2000’s, the National Sheep Improvement Program (NSIP) has been providing estimated breed values (EBVs) for parasite resistance. These EBVs have been for fecal egg count (FEC), an indicator trait of resistance. FEC EBVs have allowed producers to select for superior individuals in reducing parasite burden. But do they work?
Dr. Ken Andries, Kentucky State University
(previously published on wormx.info provided by the American Consortium for Small Ruminant Parasite Control)
Most producers of sheep and goats are experiencing resistant parasites to the common products utilized to control them. This continues to be a growing issue resulting in recommendations for change in management and selection practices. Selection for resistance can improve overall parasite status of a herd and reduce the need for treatment. Finding the individual within the breed that is more resistant is the issue when using selection.
Animal production losses associated with internal parasitic infection continues to be of great concern in the small ruminant industry. This is due to the development of parasitic resistance to chemical de-worming products.
For example, when a de-wormer is given at a lower dose than what is recommended on the manufactures label, the parasite in the treated animal may not receive an effective or lethal dose. A concern with treating lactating ewes is that Continue reading →
Sorting through the information on sheep and goat parasite control: A decision making support tool is now available.
Farmers confronted with parasite infections in their sheep and goats soon realize there is no “magic bullet” or “one size fits all” solution. They can be quickly bombarded with a lot of information available on internal parasite control but with no help in sorting out which options they should consider in their farming operation.
OSU Extension personnel have developed a decision making support tool for farmers to develop Continue reading →
An important component of summer management is internal parasite control. By this point in the calendar year sheep, and/or goats on many farms have rotated through pasture paddocks at least a couple of times. Lactating ewes and does can shed large numbers of parasite eggs, effectively seeding pasture paddocks with parasite larvae that are waiting to be ingested with the next grazing pass. As young lambs and kids learn to graze at the side of their mothers, they are very susceptible to acquiring large parasite infections. However, parasite loads are not equally distributed within the herd or flock.
Over the past several years targeted selective de-worming treatment of sheep and goats has been promoted as one way to avoid treating the entire flock or herd. Selective treatment can slow down the process of the parasite acquiring chemical resistance and thereby prolong the effectiveness of those chemical de-wormers available to sheep and goat owners. One tool that is being used to determine selective treatment is the FAMACHA system. Continue reading →
A number of sheep and goat owners have been trained across Ohio in the use of the FAMACHA system, yet problems with internal parasites, in particular, with Haemonchus contortus continue. This is to be expected. The FAMACHA system utilizes an eyelid scorecard that can help a farmer make a decision to treat or not to treat the animal with a chemical de-wormer. The FAMACHA system is not a cure-all, or a silver bullet for dealing with internal parasites. It is one tool that can be a part of an overall parasite control strategy. In order for this tool to be effective Continue reading →
May through early June is generally a time of good pasture growth and corresponding livestock production. However, if you are grazing sheep and goats this is the time of year that needs careful consideration in regards to internal parasites, in particular Haemonchus contortus, the barber pole worm. One way to approach this grazing season is to think in terms of risk management.
What can be done to reduce or minimize the risk of a heavy parasite infection while sheep and goats graze pastures? Continue reading →
Reproductive performance is an important factor in determining profitability in the sheep flock. Most breeds of sheep have seasonal breeding patterns and the majority of flocks in Ohio are spring lambing. In this scenario, the peak fertility of the ewe is from late September through November. The breeding season will extend Continue reading →
The biggest enemy of pasture based sheep and goat production has got to be internal parasites and especially, Haemonchus contortus, or the barber pole worm. Its incredible reproductive capacity, an adult female can lay up to 5,000-10,000 eggs/day, combined with the fact that the infective third stage (L3) larvae can survive 60 to 90 days or more on pasture during Continue reading →
July through September are critical times to closely monitor the internal parasite burden of lambs and kids. Preferably monitoring would start in June. The internal parasite of principal concern during the summer months is Haemonchus contortus, the barber pole worm. Lambs and kids grazing on pastures that are contaminated with large numbers of infective Haemonchus contortus larvae can go downhill very rapidly in July and August. It would not be uncommon that within a 7-10 day period Continue reading →
July and August are critical months to control the internal parasite, Haemonchus contortus in pasture based sheep and goat production. Often producers may find that lambs and kids seem to “stand still” during the summer, with little or no weight gain. There can be several reasons for this situation. Continue reading →
Raising sheep within a pasture based production system presents the manager with two challenges; internal parasite control and summer slump production of cool season pastures. The use of a warm season annual like sudangrass may offer the pasture based sheep producer a parasite control option while at the same time filling in the forage production slump demonstrated by cool season pastures during the hot summer months. In this article, I’ll draw on some of the results and lessons learned using sudangrass during the summer of 2007 on the Curt Cline farm in Athens County. Continue reading →