OSU Sheep Team

Registration Form

What: Statewide Sheep Shearing School

When: October 3-4, 2008

Where: Curt and Wendy Cline Farm
- 2551 Keck Rd., Albany, OH 45710 (Athens Co.)

Who: Any one interested in learning to shear sheep

Instructor: Bob Taylor, Professional Sheep Shearer

Cost: $35.00 per participant

Participants are responsible for there own lodging, meals, etc. It is recommended that participants bring a sack lunch and snacks both days due to the travel time it would take to get a meal. There are available hotels in the Athens, Ohio area.

Contact: Roger A. High, 614) 246-8299 or (614) 292-0589 or high.1@osu.edu, or visit our website at http://www.ohiosheep.org for more information.

Sponsored by: Ohio Sheep Improvement Association and Ohio State University Extension

Send Registration form with payment by September 19, 2008 to:

Roger A. High, Executive Director
Ohio Sheep Improvement Association
280 N. High St., P.O. Box 182383
Columbus, OH 43210

Name: _______________________________________________________

Address: _____________________________________________________

Telephone: __________________ Email: ___________________________

Interest in learning to shear:
_______ Shear my own sheep _______ Other _____________________
_______ Shear professionally

Payment enclosed: ______________________________________________

SUMMER PARASITE MANAGEMENT

Rory Lewandowski, Extension Educator, Athens County

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. One is that the nutrient level needed for good gains is not being provided, in other words, pasture quality is low. Another reason is that the animals have a parasite burden that prevents them from gaining weight. Finally, for those animals born in the February/March period, a natural immune response to internal parasites may be starting to develop. While this is important in the long run, this immune response exerts an additional nutrient demand upon the animal. In addition, the immune response can be overwhelmed by heavy parasite infections. In many cases, poor weight gain is a result of a combination of these factors.

Pasture management and monitoring of animals for parasite infection must be practiced as part of an internal parasite control strategy. The old saying, “know thy enemy” is appropriate since it is hard to make good pasture management decisions or know how to properly use monitoring tools without understanding the biology and lifecycle of Haemonchus contortus.

Haemonchus contortus survive and begin their life cycle each year through larvae that overwinter on pasture and/or through larvae “hibernating” in a process called hypobiosis in the abomasum of the host animal. This hypobiosis is actually an arrested development stage of the L4 larvae. In early spring, generally around lambing/kidding time, these L4 larvae resume the normal lifecycle, become adults and start laying eggs that are passed in the feces of the animal. So in the spring, adults and lambs can begin to accumulate Haemonchus contortus from consuming overwintered larvae, or from larvae emerging from newly deposited eggs.

Once an egg is deposited on pasture, if there is moisture and warmth, the egg hatches and a larva emerges, termed an L1 larva. Larvae need to go through a couple of growth stages to reach an L3 larva, which is the infective stage. L3 larvae migrate up and down grass blades in films of moisture. The time to go from egg to L3 infective larvae can be as short as 4 to 5 days under ideal temperature and moisture conditions. Once L3 larvae are ingested by grazing animals they travel to the abomasum or true stomach of the host animal. Larvae attach to the abomasum wall and begin to feed on blood. Within 2-3 days L3 larvae develop into L4 larvae and then adults. Once adulthood is reached, about 14 days are required before egg laying begins. The entire life cycle from egg to egg can be completed in as little as 21 days. Once egg laying begins, the female Haemonchus contortus can lay up to 5000 eggs per day. As life cycles are completed, pastures can become heavily contaminated.

It is important to realize that the L3 infective larva can survive on pasture for up to 90 days in the summer, and up to 180 days when they develop in the fall. This obviously presents some difficulties in a rotational grazing system. For example, let’s say a pasture was grazed by ewes or does in October. This means that eggs being deposited at that time could result in some overwintered larvae still being around in April. By April ewes and does will have resumed shedding eggs, and in many years, pastures managed under rotational grazing are ready to graze by early April. New eggs are being deposited, infective larvae are being ingested, and here we go. By time that paddock has been rotationally grazed a couple of times, watch out! This is what would be termed a “hot” pasture. It might look like good green, succulent grass, high in quality, but it can be teeming with infective L3 larvae. Even a pasture paddock that started out more than 180 days removed from a previous season grazing pass can become a hot paddock after a couple of grazing passes with ewes, does, lambs and kids shedding eggs.

What are management options? They must revolve around trying to keep parasite levels low. Keep a pasture log/record of when paddocks were grazed and the length of time pasture paddocks were grazed. Start the grazing season on pastures that are likely to have very low levels of overwintered larvae. Rotate to a new paddock within a 5-day period to insure animals are not ingesting infective L3 larvae. A critical piece is to have some safe pastures that have very low or no parasite larvae on them to graze in July and August. This could be a pasture that has not been grazed since the previous fall, a paddock that might have had a grazing pass but then been allowed to grow for hay harvest, or a summer annual forage. Weaning time can also play a role in how pastures are used. Once a lamb or kid has been weaned from the ewe or doe, and the stress of lactation removed, the ewe or doe can tolerate some parasite infection. The immune response provides some protection. So keep some safe pasture for weaned lambs/kids and then the ewes and does can go back and graze some of those pasture paddocks that contain infective L3 larvae.

The other management piece is monitoring animals. There are several tools available, including the FAMACHA eyelid color system and fecal egg counts. Both of these tools should be used on a consistent and regular basis to be effective. Used regularly, they provide trends that tell the livestock owner what is happening on the pastures and within the animal regarding parasite levels. Contact a member of the OSU Extension Sheep Team for more information about using these parasite-monitoring tools.

Notice that nothing has been said in this article about regular use of a chemical de-wormer. That is a road we don’t want to travel due to limited chemical options and big problems with parasite resistance to chemical de-wormers. Every sheep and goat farm that is serious about long-term production needs to know which of the chemical de-wormers, if any, work in their flock/herd and then save the use of that chemical for rescue treatments and selective de-worming as determined by regular monitoring.

REFERENCES:

Managing Internal Parasitism in Sheep and Goats

Kate Hepworth, Mike Neary, Terry Hutchens

Parasite Control in Sheep: Biologic Approaches for the New Millennium

William P. Shulaw and Clifton M. Monahan

Ohio Forage And Grassland Council’s Sheep Grazing Farm Tour, will be held Friday, July 11, 2008, from 9:00 a.m. – 4:30 p.m. Meet at the Athens County Fairgrounds, 280 West Union Street, Athens, Ohio, Cost is $25:00 for OFGC Members, and $30.00 for non-members.

Includes bus transportation and roast lamb lunch

Stops:

Ben and Kelly Kasler Farm

A third generation purebred sheep operation with about 50 Suffolk ewes. See an established stand of reed canarygrass as well as a new seeding of orchardgrass, festulolium and clover.

Strode Family Farm

This farm has been completely converted to grass farm within the last twelve years. There are about 50 Angus based brood cows and 50 Polypay ewes grazing the farm. Rotational grazing is practiced with a gravity fed water system that has a mile of water pipe. The family sheep shearing trailer will be available to view.

A roast lamb lunch with all the fixings will be served.

Dick and Nancy Howard Farm

This diverse grazing farm has 14 Suffolk crossbred ewes, 30 crossbred beef cows and 90 Boer crossbred does. Dick and Nancy have an Environmental Quality Incentive Program contract to assist in constructing access lanes, pasture subdivision fences and a watering system. You will also see a handling system for the sheep and goats.

Registration Deadline is July 3, 2008

Make Check Payable to: Ohio Forage and Grassland Council, send it to: Ohio Forage and Grassland Council, P O Box 488, Coshocton OH 43812

For a pdf flyer click Here.

Rory Lewandowski, Extension Educator Athens County

Ohio Sheep Day is scheduled for Saturday, July 12. It will be held on the Cline family farm, located just outside of Albany Ohio in Athens County. Curt Cline was the 2007 Ohio Sheep Improvement Association Environmental Stewardship Award winner and at the recent American Sheep Industry meeting was named the national Environmental Stewardship Award winner. Curt is currently serving as a director on the board of the Ohio Sheep Improvement Association.

Curt and Wendy Cline run a forage based sheep operation and are currently undergoing an expansion of their sheep flock that will take them from 120 ewes to 300 plus ewes by the time Sheep Day arrives. The expansion is the result of some significant management changes that revolve around internal parasite control, more intensive use of traditional and alternative forages and the economic potential of the Ohio sheep industry. Visitors to the Cline farm during Sheep Day can expect to hear about the importance of economic analysis as a base to decision making.

The 2008 Sheep Day at the Cline farm will focus on forage demonstrations, grazing management and stored forage use. A partial list of what visitors will see includes:

• Fall (2007) seeded grass plots
• Fall (2007) seed grass plots frost seeded in late winter 2008 with red and white clover
• A Tekapo orchardgrass field established in 2004, interseeded/frost seeded in late winter of 2008 with red and white clover, using grazing sheep to insure good seed/soil contact
• Forage chicory field
• Several fields of Brown Mid-Rib (BMR) sudangrass and sorghum x sudangrass hybrids being strip grazed by sheep
• Surplus BMR sudangrass and sorghum x sudangrass forage harvested/chopped and stored in silage bags
• Paddock and water system for cool season grass pastures

In addition to talking about the agronomic characteristics of forages used on the farm, other topics that will be addressed include:

• Soil fertility management using grid sampling and GIS fertilizer application on pasture paddocks
• Internal parasite management within a rotational grazing system
• Handling and caring for foot rot
• Economic issues and considerations in a forage based sheep operation
• Utilizing cost-share assistance programs like EQIP to protect the environment and improve grazing management

There will also be vendors/exhibitors dealing with all aspects of sheep production.

Ohio Sheep Day will offer visitors the opportunity to visit a farm that has been in the Cline family since the late 1800’s where today 3 generations come together to live and work. Curt and Wendy are excited about the future of agriculture and the opportunities for profit that a sheep operation can generate. Sheep owners and anyone interested in forage management is cordially invited to Ohio Sheep Day at the Cline farm in scenic Athens County.

Don’t forget to mark your calendars for July 11 as well as once again the Ohio Forage and Grassland Council will be sponsoring a pre-Sheep Day tour of some area farms. More details will follow.

DIRECTIONS TO THE CLINE FARM; SITE FOR OHIO SHEEP DAY –

From Columbus take U.S. 33 East to Athens and then SR 32/50 West to Albany. At the traffic light in Albany turn right, go past the Marathon gas station down to Lee Street. Turn right on to Lee Street (Hocking Valley Bank on the corner), go 1 block and then turn right on to SR 681. Go approximately a quarter of a mile and turn left on to Factory Road. Go 1.25 miles on Factory Rd to 3933 Factory Rd and you have arrived at the Cline Family farm.

For a pdf flyer visit here

Becky Talley, Sheep Industry News Associate Editor

In February of last year, the U.S. Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APHIS) officially announced the discovery of a Nor98-like scrapie case in a ewe from a flock in Wyoming. This was the first case of scrapie consistent with Nor98 discovered in the United States.

Since then, four more cases have been discovered that originated from flocks in Colorado, Indiana, Minnesota and California. These cases are not related to either the first one in Wyoming or to each other.

This scrapie type was first found in Norway in 1998 and has since been found in sheep and goats in many countries in Europe.

“It does affect goats,” says Diane Sutton, DVM, national scrapie coordinator for USDA. “So far not here in the United States, but chances are, we might eventually see it in goats here too.”

This type of scrapie affects sheep of all commonly occurring genotypes including those that are resistant to classical scrapie.

According to Sutton, those flocks in the United States that are found to be infected with Nor98-like scrapie will not be able to use the current genetic-base approach to flock clean up. Producers whose flocks have risk factors for classical scrapie are still encouraged to test at codon 171 for classical scrapie resistance, as has been done in the past.

The World Organization for Animal Health (OIE) has formed an ad hoc committee to consider how to address Nor98-like scrapie with respect to trade. It will likely be at least two years before a code change could be made should a consensus be reached.

“Until research provides us with other options for eliminating Nor98-like scrapie and the international community reaches a consensus on guidelines for trade we will continue to use flock depopulation and exposure-based clean up plans for Nor98-like scrapie affected flocks,” says Sutton. “As other viable options are identified, we will evaluate them using pilot projects.”

According to Linda Detwiler, DVM, assistant director, Center for Public and Corporate Veterinary Medicine, it is important to note that it isn’t known if the appearance of non-classical scrapie cases in Europe and the United States are more likely due to the increased ability to test for and detect non-classical scrapie than to increasing rates of infection. Scientists in European countries are beginning to look at archived samples in an attempt to identify non-classical cases that may have occurred earlier than 1998.

“I would caution everyone that it’s premature to be able to say much of anything about these non- classical cases. At this point in time, there are many unknowns such as: 1) is there more than one strain, 2) what is the origin, 3) are there natural modes of transmission, 4) does the genotype affect incubation time and clinical presentation, 5) do codons other than 136, 141, 154 and 171 influence these cases and 6) how long have these cases been occurring?” she questions.

Because of Europe’s increased awareness of non-classical scrapie, there has been quite a bit of research into understanding how and if the disease is transmitted and how it affects sheep.  Research is currently underway in the United States.

“The first U.S. material became available in February, so ARS (Agricultural Research Service) is gearing up to study it. But, because of the nature and long-term aspects of the disease, it will take a while to study, so we will probably be seeing research from Europe published first,” Sutton adds.

In the meantime, it is stressed that officials will continue to handle the disease as it has in the past, and that producers should be aware of Nor98-like scrapie but not alarmed.

“We are going to treat it as scrapie until the international community removes it as a trade barrier or science finds that there is a better way to handle it than the current system,” Sutton says.

Jim Logan’s, DVM, chair of ASI’s Animal Health Committee, best advice to producers to protect their flock from Nor98-like scrapie is to maintain a closed ewe flock. He says that to prevent the introduction of all scrapie types, producers need to be aware of where new purchases are coming from, know the genetics of new purchases and avoid purchasing ewes unless familiar with the scrapie status of the farm of origin or maintain a closed ewe flock.  “Essentially, people need to use common sense and maintain good sanitation and husbandry practices,”he explains.

The Science Behind Nor98 in Sheep

Nor98 is a relatively common prion disease or transmissible spongiform encephalopathy of sheep. The first descriptions of the disorder were in sheep diagnosed in 1998 in Norway, although a retrospective study has revealed a case in England in 1989. Improved methods for diagnostic testing were published in 2002 and surveillance was initiated in many European countries. Most cases are identified in clinically normal sheep tested in routine slaughter surveillance. The disease is experimentally transmissible to sheep and genetically altered mice by inoculation into their brains but no data are yet available on whether the disease is transmitted between sheep in an affected flock.

CLINICAL SIGNS
Most cases have been discovered in clinically normal sheep tested at slaughter. Of the few clinical cases, a common sign is progressive incoordination (ataxia), occurring most likely because the abnormal prions accumulate in the cerebellum, the region of the brain (the cerebellum) that integrates information coming in from the senses with nerve impulses going to the muscles.

DIAGNOSIS
Both classical scrapie and Nor98-like scrapie are characterized by accumulation of abnormal prion proteins. However, the distribution of the prion proteins differ. In classical scrapie, prions are usually found earliest in the lymph nodes and later in the region of the brain associated with innervation of the gut. As discussed above, abnormal prions are found in different areas of the brain in cases of Nor98. Further, prion proteins are not found in the lymph nodes of sheep with Nor98 and the current live animal tests of lymphoid tissues are not suitable. Nor98 is a challenging diagnosis but skilled pathologists, working with a panel of three different diagnostic tests, can accurately diagnose the disease in the brain of affected sheep.

GENETICS
Susceptibility to classical scrapie is associated with naturally occurring differences in the gene for the prion protein, particularly differences at position 136 and 171. Each sheep has two copies of this gene and commercially available genotype tests show the differences at those positions. Sheep with the genotypes 136VV 171QQ and 136AV 171QQ are very susceptible to classical scrapie strains. Sheep with the 136AA 171QQ genotype are susceptible to the most common classical scrapie strain in the United States and represent the most common genotype found in U.S. scrapie cases. Sheep with at least one copy of the gene 136A 171R are generally resistant to the more common type of classical scrapie.

Although no genotype is considered to be resistant to Nor98-like scrapie, the disorder is found most frequently in sheep with changes in positions 141 and/or 154. The genetic signature AFRQ indicates a sheep with 136A and 171Q with the additional change to “F” at 141. The signature AHQ indicates a sheep with 136A and 171Q with a change to “H” at position 154. A large survey of 4,000 sheep in Europe and numerous reports on smaller study populations has demonstrated that sheep with either the AFRQ or the AHQ gene were eight to 15 times more likely to be diagnosed with Nor98-like scrapie than were sheep with the most common genotype ARQ. Sheep with both changes were more than 20 times more likely to be diagnosed with Nor98-like scrapie. Sheep with the 171R form of the gene are generally resistant to classical scrapie but are susceptible to Nor98-like scrapie, particularly in 171QR sheep that have an AFRQ gene.

EPIDEMIOLOGY
Classical scrapie is usually found in more than one sheep in a flock, with prevalence as high as 30 percent with some scrapie strains. In contrast, more than one sheep with Nor98-like scrapie is usually found only in flocks of more than 500 sheep. In addition to genotype, age appears to represent a significant risk factor for Nor98-like scrapie. In the large European study, 80 percent of the cases of classical scrapie were found in sheep ages 3-5, a finding similar to that reported in the US. In contrast, more than 60 percent of the sheep with Nor98-like scrapie were older than five years and more than 25 percent were more than 10 years old. Nor98 is found in most countries performing large-scale surveillance; the disorder occurs at a rate of approximately one in 1,400 mature sheep at slaughter even if the rate of classical scrapie is very low.

The low prevalence of Nor98 within flocks, the wide geographic distribution of the disorder, the range in age of onset or diagnosis, and the genetic factors increasing the risk of Nor98 are strikingly different than those found in classical scrapie. There may be additional genetic factors influencing development of this disorder, in addition to factors such as route of infection or age at which sheep are infected. Alternatively, Nor98 may be a sporadic disease of sheep, appearing primarily but not exclusively in older sheep. Additional findings from experimental studies and large scale surveillance using improved diagnostic methods will be useful in understanding this wide-spread prion disease of sheep.

BACKGROUND INFORMATION
Luhken and others, 2007, Veterinary Research 38: 65-80.
Bruce and others, 2007, Veterinary Record 160: 665-666.
Benestad and others, 2003, Veterinary Record 153: 202-208.

Jeff Pelc, Wildlife Biologist USDA/APHIS, Wildlife Services, Tim Fine, Extension Program Assistant, Miami County

Black Vultures have become a serious sheep pest in certain areas of Ohio.  This article will focus on the procedures necessary to report a predation loss by black vultures to the Ohio Department of Agriculture (ODA) for reimbursement under the indemnity program.  In the next sheep team newsletter, we will take a look at options for black vulture control.

There are certain procedural steps that must be followed when dealing with losses due to Black Vulture predation.  In most cases, if these procedures are not followed, compensation by ODA for your losses may not be granted.

1.       Notify your local dog warden by telephone within 72 hours after the loss or injury has been discovered. The dog warden shall promptly visit your farm to determine whether the kill was by a predator or not.  If the dog warden determines that the kill was not by a predator then no further steps need to be taken as there is no claim under the ODA indemnity program.

2.       Document, by photograph, the injuries sustained by the animal.  This should be done immediately after contacting the dog warden.  Do not wait for the determination as to whether the kill was by a predator or not.  It is advised to leave the animal where it lay for investigative purposes.

3.       Obtain an indemnification form from the dog warden.  This form will need to be filled out and sent to ODA within 30 days of discovery of the animal by the owner.  Photos taken of the injuries and any other pertinent facts shall accompany this document.  You may request assistance from the dog warden in filling out the indemnification form.  If the animal injured or killed is a registered animal, then registration papers should also accompany the indemnification form.

4.       If the dog warden determines that the kill was by a predator then he/she must promptly contact by telephone the county’s wildlife officer.

5.       Following the notification from the dog warden, the wildlife officer must confirm, disaffirm, or state that he/she is uncertain about the determination of the dog warden on the claim. If the wildlife officer disaffirms the claim of the dog warden, the owner has no claim under the ODA indemnity program

6.       If the wildlife officer affirms or states that he/she is uncertain about the determination of the dog warden, the wildlife officer must notify the ODA, in writing, of his/her determination.

7.       The ODA will hear claims that are approved by the dog warden and supported by the wildlife officer. The ODA may decide to grant full compensation, partial compensation, or no compensation.

8.       If the owner feels that the ODA’s determination of the fair market value, he/she may appeal the determination.

For more information on the indemnity process, contact the Ohio Department of Agriculture at 614-728-6220 or at http://www.ohioagriculture.gov/animal, or contact USDA/APHIS at 614-861-8607 or on the web at http://www.aphis.usda.gov/ws/

Rory Lewandowski, Extension Educator, Athens County

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.

The internal parasite of major concern to pasture based sheep producers is the barber pole worm, Haemonchus contortus.    Resistance to all classes of chemical de-wormer currently on the market has been documented in Haemonchus contortus populations in various farms around Ohio.  The prudent sheep producer will therefore limit the use of chemical de-wormers and place emphasis on controlling parasite infections through a better understanding of parasite biology and corresponding pasture management.  A key concept is the use of safe pastures.  A safe pasture contains no, or very low levels of, infective Haemonchus contortus larvae.  This can be achieved by keeping sheep off a pasture for a period of time so that there is minimal survival of parasite larvae, or by planting an annual forage where larvae do not survive.

Under typical cool season pasture conditions the population of infective Haemonchus contortus larvae continues to build from the start of spring grazing.  By mid to late summer, after several rotations through pasture paddocks, levels of infective larvae can be extremely high and grazing lambs and milking ewes can quickly pick up levels that at best suppress production and gain, and at worst, can be fatal.  At the same time that lambs and ewes are under stress from parasite infection, pasture quality and quantity is decreasing.  In this situation a warm season annual forage like sudangrass can make a real difference.  In addition to acting as a safe pasture where parasite burdens are not increased, under hot summer conditions these forages will continue to grow and produce a high quality feedstuff.

In 2007, as part of an on-farm study investigating the use of alternative forages as a control option for internal parasites, a brown mid-rib (BMR) sudangrass from Ampac Seed Company was planted on the Curt Cline farm in Athens County.  BMR sudangrass is more palatable and produces a higher quality forage compared to a non-BMR sudangrass.  Trials in other states had shown very good animal gains on this forage.

The field was seeded on June 1 at a rate of 25 lbs/acre.  Since our 2007 trial, I have spoken with Ampac seed representatives and they are currently recommending a seeding rate for grazing conditions of 35 lbs/acre. The field had been in winter rye and was tilled using a chisel plow and disk.  Seed was applied with a broadcast seeder mounted on a 4-wheeler and then cultipacked.  The seedbed was very dry.  Soil fertility on this field was at low to moderate levels with a soil pH slightly below 6.0.  According to the Ohio Agronomy Guide, soil fertility levels should be similar to what is needed to produce a 100-to 150-bushels/acre-corn crop.  This translates into a critical soil phosphorus level of 15 ppm and a soil potassium level of 100 ppm at a cation exchange capacity of 10.  Following a grass sod, nitrogen requirements range from 60 lbs/acre for a 3-4 ton yield goal to 100 lbs/acre for a 5-6 ton yield goal.  Seed should be planted one-half to one inch deep on a firm seedbed.  Recommended planting time is from late May until the end of June.  Soil temperature should be in the 60 to 65 degree F range.

Rain was in short supply in 2007 and the prepared seedbed was too dry initially for the BMR sudangrass seed to germinate.  On June 4 a quarter inch of rainfall provided enough moisture for seed germination.  Fortunately, an isolated thunderstorm brought 1.3 inches of rain to the farm on June 9-10.  From this point on the BMR sudangrass made rapid growth.  On July 12, several days before the first grazing pass with lambs was begun, random samples were collected from the field, and a dry matter yield was calculated at 3000 lbs/acre.  By the time the lambs were turned into the field several days later, some additional growth had occurred and the field averaged about 40 inches in height.  We recognized that grazing should have begun earlier, but due to other conditions of the study, this was when lambs had to start the grazing pass.  According to both the Ohio Agronomy Guide and the Ampac Seed literature, grazing should start at between 24 to 30 inches in height, and be grazed down to a 6 to 8 inch stubble.

Even though lambs began grazing the BMR sudangrass later than recommended, quality samples collected on July 16, the day the lambs entered the field, came back from the lab with an analysis of 20% crude protein and 68% TDN.  This quantity and quality of forage was produced during a period with limited rainfall and daytime temperatures in the 90’s.  During this same period cool season grass pastures were shutting down, recording low levels of dry matter accumulation.

Something that producers need to consider regarding a warm season annual like sudangrass is how to best utilize the production capacity of the forage.  Since the forage grows rapidly, it is similar to managing the spring flush of cool season pasture growth.  It is very easy for the forage to get ahead of animal consumption, leaving a field of mature, declining quality forage.  This happened to us at the Cline farm, and half the BMR sudangrass field was fenced off and cut for hay when it became apparent that there was more forage than could be consumed in a timely manner by the number of livestock available to graze.

The Ohio Agronomy Guide says that when a 6-8 inch stubble is left, plants should re-grow to the 24 to 30 inch grazing height in 2 to 3 weeks.  This is consistent with what was observed on the Cline farm.  So, getting back to a management strategy to best utilize the forage quantity being produced, while also taking advantage of the high quality that is possible, the producer may want to consider staggered plantings of the sudangrass at 2 week intervals, or plan to do a cutting for hay or silage on part of the acreage.  A sample planning calculation might look something like this: Sudangrass at 24-30 inches of height producing 2500 lbs of dry matter (DM)/acre.  Ewes at 170 lbs consuming 3% of body weight per day need 5.1 lbs of DM.  If the field is strip grazed, forage utilization should be at least 70%, so 2500 lbs of DM x .70 = 1750 lbs of DM available.  If we want a 2 week grazing period, this will allot 125 lbs of DM / day, so we could graze 25 ewes/acre for 14 days.  If 70-pound lambs were the grazing animals, and we figure dry matter consumption at 4% of body weight, then 45 lambs could be grazed on this acre for 2 weeks.  If we had staggered planted a second acre of sudangrass 2 weeks after the first, or harvested the second acre as stored forage when grazing started, it would now be ready for a grazing pass.  In reality, because the sudangrass will continue to grow and add dry matter from the time the grazing pass is begun, more animals will be needed to keep ahead of forage growth.  However, this example illustrates the potential available during a time when forage is generally in short supply.

In addition to the forage production supplied by the BMR sudangrass, it also provides a safe pasture free from infective parasite larvae.  The process involved in establishing the sudangrass destroys any larvae that might have been present if a previously grazed sod is used.  Based on the experience at the Cline farm, even if infected sheep/lambs are moved on to the sudangrass, the shed eggs and resulting infective larvae are unlikely to add to the worm burden of grazing animals in subsequent grazing passes because: 1) leaving a 6 to 8 inch stubble insures no, or very few larvae will be ingested as typically infective larvae are found on the first 3 inches of grass plants, and 2) the structure and spacing of sudangrass stems will make it difficult for larvae that hatch from eggs in the feces to cover the distance needed to crawl up stems.

During the course of the study on the Cline farm it was found that while lambs were grazing with their mothers they had developed high levels of parasites.  It was later discovered that the parasite population on the farm had resistance to all chemical de-wormers except for Cydectin.  This was not documented until late in the season, shortly before beginning the second grazing pass on the BMR sudangrass on August 21.  As a result, lambs maintained high parasite numbers for most of the project.  While many of the lambs demonstrated resilience to these high parasite numbers as indicated by FAMACHA eyelid scores of 1 and 2, performance still suffered.  As an example, just before the lambs entered the BMR sudangrass on August 21, lambs scoring a 3 or higher on the FAMACHA eyelid scorecard were de-wormed using Cydectin as a rescue treatment.  This amounted to 7 lambs out of the 20-lamb study group.  The remaining 13 lambs were not treated.  At the end of a 3-week grazing pass on the BMR sudangrass, the untreated lambs had gained 0.19 lbs/day, while the treated lambs had gained 0.42 lbs/day.

There are several lessons here.  One is that early season pasture management is critical to avoid loading up ewes and lambs with high parasite burdens.  Two, make sure you know what chemical de-wormers really work in your flock.  Finally, a warm season annual like sudangrass can provide a high quality forage when cool season pastures are declining, but that quality is put to best use in terms of animal performance when heavy parasite loads do not stress animals.

In summary, a warm season annual like BMR sudangrass can be used to provide a safe pasture while producing good tonnage and good quality during a time cool season pastures have little growth.  To most effectively utilize this forage, a producer must have a plan to manage the rapid growth, including adequate animal numbers, strip grazing, staggered plantings and/or the capacity to harvest surplus growth.

Gary Wilson, Extension Educator, Hancock County; Jonah Johnson, Extension Educator, Clark County; Woody Joslin, Extension Program Assistant, Shelby County; and Tim Fine Extension Program Assistant, Miami County

In September 2007, the OSU Extension Sheep Team traveled to Virginia Polytechnic Institute in Blacksburg, Virginia to observe current, cutting edge research in sheep production.  The ten team members making the trip included producer and industry leaders in addition to Extension staff.  Virginia Tech is one of the leading Land Grant Universities the nation that is very fortunate to have a strong faculty of research professors that lead the way with expected progeny difference (EPD’s) work, determining inherit traits, as well as determining parasite resistance among sheep and goat breeds.  The Sheep Team was also fortunate to tour the USDA‘s Appalachian Farming Systems Research Center in West Virginia.

A majority of this educational experience occurred at the Animal Sciences facilities at Virginia Tech.  After a brief tour of the facilities, the group was introduced to Dr. David Notter, his research associates, as well as an introduction to the research being conducted at the research center.  Research projects included using ultrasound to determine genetic inheritability traits, determining parasite resistance across various breeds of sheep and goats, and using various genetics to procure “out-of-season” breeding.

Following the Virginia Tech research tour, the OSU Extension Sheep team spent the day at the USDA-ARS research center in Beaver, West Virginia.  A majority of the research conducted here is focused on forage production, specifically annual and perennial forages, and how different production practices maximized the species ability to succeed into “extended” grazing periods.  Other research being conducted on the Station is parasite resistance work within goat herds to examine different parasite loads among different forage grazing situations.  One other area of interest was managing forest areas, where producers manage a forest for timber but also use the grass available in these areas to graze livestock.

Jeff McCutcheon, Extension Educator, Knox County

After the dry growing season last year many sheep producers are asking what they could do to improve pasture yields.   Other than improving soil fertility there is one thing you can do during the month of May that will improve yields.  In fact most experienced graziers I know get pretty fanatical about this task.  The task is simple; remove the reproductive tillers before they produce seed.  In other words do not let your pasture plants have sex.

The reason you do not want to see reproductive tillers is because letting the grass plants produce seed will decrease yield.  Reproductive tillers reduce yields in two ways.  First, reproductive tillers elongate above the other tillers on the plant and shade out the vegetative tillers.  This competition for sunlight means that the vegetative tillers are growing less.  Less sunlight reaching the crowns of the grass plants also means that fewer vegetative buds on the crown will develop into tillers.  Yield in pastures is heavily influenced by the density of the pasture.  More tillers are better than more height.

The second way reproductive tillers reduce yield, is by producing hormones as the seeds mature that retard or inhibit the development of other vegetative tillers. The grass plant will not produce more vegetative growth until the seeds completely mature or the reproductive tiller is removed.  Remember, the plant’s priority is to put its resources into the development of a mature seed, not to grow high quality vegetative material.

When should you remove the reproductive tillers?  To keep our pastures vegetative, reproductive tillers should be removed between boot and flowering.  During spring we have warming temperatures with increasingly longer days and shorter nights.  Each grass plant has multiple tillers.  Initially in the spring all the tillers produce vegetative growth.   For each grass there is a range of light to dark time where those tillers induced to flowering when they were developed last fall, switch from vegetative growth to reproductive growth. The tiller elongates and stem formation begins. The tiller now shifts its resources to seed development and further leaf production on the tiller stops. The seed head develops and is pushed up and out of the tiller. Boot stage is when the seed head is just about ready to emerge from the last elongated node area and is still wrapped in a leaf sheath. After the seed head emerges from the leaf sheath the reproduction continues with flowering, seed development, seed growth and seed maturation.

Unlike vegetative tillers that have the growing point near the soil surface, the growing point in a reproductive tiller is generally found just below the last completed node. This growing point is vulnerable to grazing or clipping.  If the growing point is removed then re-growth will come from the development of new tillers.

One caution, there can be more than one reproductive tiller on a plant.  Even though our cool season grasses produce seed heads in the spring, those tillers were actually developed during the preceding fall.  Cool season grasses require a period of cold temperature with long nights to develop flower buds on the crown of the plant.  Once reproductive growth is initiated in the spring, one reproductive tiller will dominate.    If reproductive tillers are removed and light conditions are still right to initiate reproductive growth another tiller initiated last fall will start reproductive growth.  I have seen orchardgrass three inches tall with a flowering seed head.

Because of this some sheep producers may want to wait until most of the reproductive tillers have developed seed heads before clipping later in the grazing season. You could wait but you will lose yield.  Two of my colleagues have said that clipping after flowering is either cosmetic or for revenge, not to stimulate vegetative growth.

Every tiller on a grass plant is not a reproductive tiller. Only those tillers induced the preceding fall have the capacity to produce a stem and seed head; the new tillers developed in the early spring will not produce a seed head.  Eventually the light conditions will change, no longer initiating reproductive growth, and all the growth for the rest of the year will be vegetative.

Removing reproductive tillers can be accomplished with grazing livestock or mowing.  Livestock can best do this with high stocking densities and moving livestock quickly from one paddock to the next. The goal is to use the livestock to just graze the top couple of inches of the grass. To effectively do this a heavy stocking density and small paddock size is needed.  If the grass is not grazed uniformly enough to avoid seed head formation, then some mechanical clipping will be needed.

Roger A. High, State Sheep Extension Associate

(Originally Published in Sheep Team Newsletter April 2003)

As many producers near the end of lactation, it is time to remind ourselves about an appropriate pre-weaning and weaning plan to prevent loss of udders due to poor weaning management.  The current SID book has these weaning recommendations:

1) Dry ewes off by deprivation of feed for 48 hours and water for 24 hours.  Provide low energy and protein for the next 10-14 days. This is the time of the year to feed your poorest quality hay to the ewe flock.   Monitor ewes closely for evidence of acute mastitis.

2) Sort and cull unsound ewes.  Unsoundness in a ewe would include mastitis, lameness, excessive thinness, non-lactating, poor teeth (molars and incisors), etc.

3) An internal and external parasite program and an appropriate immunization program must be tailored to each operation.  This should be planned with the help of a veterinarian.

4) Since water is the main portion of the milk produced by the ewe, it is important to reduce water intake prior to weaning.  This will reduce milk production in the ewe.

For most of the purebred and club lamb operations and those commercial flocks that are raising lambs in the barn, the normal weaning time is around 60 days after those lambs are born.  This is the time period when milk production in the ewe is becoming lower and the lambs are in need of higher quality nutrition than the milk can provide.  It is more efficient to feed the lambs than it is to feed the ewes to maintain low levels of milk production.

For commercial grazing operations, there is no real set date for weaning.  Generally these flocks will let the ewes wean the lambs themselves.  At around 90-100 days of age, the ewes will no longer allow the lambs to nurse, and milk production is very low.  The lambs will be grazing and providing nutrition to himself or herself either in a creep or on the pasture that there dams are grazing.  The wether lambs can then be removed from the ewe flock and either marketed as feeder lambs or fed out by the producers and sold later as finished lambs at a later date.  Ewe lambs are generally maintained with the ewe flock or separated from the ewe flock and maintained on a higher plane of nutrition.