Increase Lamb Crop by Testing for Pregnancy


Reviewed by: Jay Parsons, University of Nebraska-Lincoln and Bill DeMoss, Mountain Vet supply
(Previously published online with Agriview: September 5, 2019)

(Image Source: U.S. Lamb Resource Center)

Pregnancy detection in the ewe provides the opportunity to adjust nutritional and lambing management to save on feed and labor costs. The old adage that “one open ewe takes the profits of five producing ewes” may be true when all costs are calculated. Early determination of fetal numbers and gestational stage gives the option of sorting for nutritional demands in late pregnancy and early lactation. Without that information, the single-bearing ewe is being fed too much or the twin-bearing ewe too little. Open ewes are robbing the pregnant ewes of necessary nutrition. Grouping according to gestational stage will also save on labor and allow for better utilization of facilities and biosecurity.

The key in any type of business is producing an end product, or more simply put, production. The economic benefit of pregnancy testing in Continue reading

Reproductive Management of the Ewe Flock and the Ram

Mike Neary, Extension Sheep Specialist, Purdue University
(Previously published on the Purdue University Extension web page)

(Image Source: Michigan State University)

The most important factor in determining profitability of a sheep enterprise is production rate. Productivity of the ewe flock is a direct reflection of reproductive efficiency. Regardless of genetic merit, eye appeal, price, or showring placing, if a sheep will not reproduce it is worth no more than current slaughter value.

To a large extent, the goals and objectives we have for our next lamb crop are determined before and during the breeding season. Increasing ewe productivity while decreasing labor, time and facilities requirements during the lambing season can be realistic objectives.

Reproduction in sheep is influenced by numerous factors. These include: Continue reading

Reproductive Physiology of Sheep

Paula I. Menzies, DVM, MPVM, DECS-RHM, Ruminant Health Management Group, Department of Population Medicine, Ontario Veterinary College, University of Guelph
(Previously published in Merck Manual: Veterinary Manual: June, 2015)

(Image Source: Cornell Small Farms – Cornell University)

Ewes are seasonally polyestrous,cycling every 16–17 days during the breeding season. The major environmental factor controlling the estrous cycle is the photoperiod. Decreasing photoperiod after the summer solstice causes secretion of melatonin, which triggers the hypothalamus to produce gonadotropin-releasing hormone. Geographic location and environmental temperatures also modify the length of anestrus, as does the breed of sheep. Fine-wool breeds (eg. Rambouillet and Merino), tropical breeds, and Dorsets have a shorter anestrous period than other breeds such as the Suffolk, Hampshire, Border Leicester, and Columbia. Regardless of this breed-related variation in the length of the breeding season, all breeds are most fertile in the autumn, and anestrus is an unlikely problem associated with regular annual mating.

The duration of estrus (~30 hr.) is influenced by Continue reading

Flushing Small Ruminants for a Higher Ovulation Rate

Michael Metzger, Michigan State University Extension Educator
(Previously published on MSU Extension, Sheep & Goat: August 6, 2018)

(Image Source: Sheep 101.info)

Increasing the level of nutrition for does and ewes 2-3 weeks prior to and 3 weeks into the breeding season can improve kid/lamb crop in some instances.

When managing a goat/sheep herd farmers are always looking for ways to improve their herd, increase production and raise profitability. One way that a farmer can accomplish this is to implement flushing into their breeding practices. Flushing is a temporary but purposeful increase in the level of nutrition around breeding time. This is done to boost ovulation, conception and embryo implantation rates. Flushing may also increase the proportion of females that exhibit estrus. Flushing can increase lambing and kidding rates by 10-20 percent. This is important because a flock’s lambing/kidding rate is one of the primary factors influencing profitability. Flushing works best in

Continue reading

Breeding Soundness Examination of the Ram and Buck

David C. Van Metre, DVM, DACVIM Extension Veterinarian, Colorado State University
(Previously published online with Veterinary Extension through Colorado State University)

(Purdue Extension, Purdue University)

Veterinarians are well positioned to become valued participants in sheep flock and goat health programs through introduction of certain practices that have high potential to provide direct economic benefit to the producer. Opportune times for veterinary intervention include evaluation of the breeding flock in the fall prior to breeding, late fall / early winter pregnancy diagnosis, and lambing / kidding during the spring. To optimize the size of the following spring’s lamb or kid crop, the primary goal of the pre-breeding health program should be optimization of fertility through nutritional management and disease control measures, as well as documentation of Continue reading

Preparing the Flock for the Breeding Season

Dr. Scott Greiner, Extension Animal Scientist – Sheep, Virginia Tech
(Previously published on the Virginia Cooperative Extension web page)

If you can believe it, we are already in the first week of June! The reality of breeding season is real for some of our breeders here in the state of Ohio. Others may be several months out, however, regardless of when you will begin the breeding season on your operation it is important to be prepared. Breeding season is more than just joining ewes and rams together, it takes months of preparation prior to this to ensure a successful season. Although this article has some age, it still remains to be a nice checklist on how to manage your rams and ewes prior to the breeding season.

Rams:
High temperatures can be detrimental to ram fertility, reducing pregnancy rates and lambing percentages. Heat stress occurs when the scrotum is not able to reduce the temperature of the testicles below normal body temperature. Although heat stressed rams may Continue reading

Good Choices on Rams Now Translates to Good Flock Production Later

James Thompson, Sheep Specialist (retired), Oregon State University
(Previously published on with the Oregon State University Extension Service)

There is no room for snap judgments when selecting breeding sheep. Next year’s lamb crop depends on our choices now. Take the time and the gas to drive around and look at prospects. Always keep your improvement plan in mind; choose only rams and ewes that will move you toward your goal. The ram contributes 80% – 90% of the genetic improvement to the flock. A good ram does not cost—it pays. An outstanding sire can’t be purchased for market price, and you can’t expect outstanding lambs from a scrub ram. Keep the following in mind as you look at prospects: Continue reading

Minimizing Genetic Defects in Sheep

New Mexico State University Extension
(Previously published on the NMSU Extension web page)

As we dive head first into the 2020 lambing season, be sure to keep a close eye on your lamb crop. I know what you may be thinking, everyone already does this and I hope that is true. Keeping lambs healthy, warm, fed, and alert are key to a successful lambing season. However, you also need to take into account and record any type of defects. As noted below, these defects may not be life threatening, but a defect in the genetics of your flock is not worth the hassle. Once a genetic defect is found, be sure to record this information in your lambing records so you can properly deal with this issue when it comes to culling the appropriate animals from your flock.

Fortunately, sheep have few inherited defects that reduce their survival or producing ability. A discussion of the major genetic defects follows.

Jaw defects
Jaw defects are present in almost all breeds of sheep and are associated with failure of the incisor teeth to properly meet the dental pad. A jaw is

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Factors Affecting Reproductive Performance of Sheep

Paula I. Menzies, DVM, MPVM, DECS-RHM, Ruminant Health Management Group, Department of Population Medicine, Ontario Veterinary College, University of Guelph
(Previously published online with the Merck Manual – Veterinary Manual)

Reasons for reproductive failure in the ewe and ram are numerous. Performance must be considered in light of the management system and genetics of the breed. If targets are not being met, the following can be used as a guideline to investigate contributing factors.

Breed:
Breed selection can greatly influence reproductive performance, particularly prolificacy and age at first lambing. Sheep breeds around the world are very diverse in performance, and it is advisable to be familiar with the traits of some of the more popular ones. Continue reading

Sharpen your Shepherding Skills with Bred Ewe Lambs!

Tim Barnes, OSU Extension Educator ANR, Marion County

As we approach the end of the typical breeding season here in Ohio, there is still a group of sheep that shepherds may consider breeding prior to the coming of the new year. Depending upon who you ask, it seems like everyone has their own opinion on breeding ewe lambs. If you recall the article from Susan Schoenian that we shared last year, To Breed or Not to Breed, Susan explains that breeding young stock allow you and your operation to exploit reproductive and genetic potential. In the same breath, do note that breeding young females may also result in some production inefficiencies such as reduced milk production and potentially dystocia issues where it may require more labor from a management standpoint. Of course its nice to breed during the latter portion of the breeding season as this allows for your ewe lambs to be more mature at the time of breeding in addition to lambing these ewes down during the spring when hopefully the weather is more desirable to work in. Regardless of your situation, it may be worth taking a look into breeding your ewe lambs yet this year. Below, Tim Barnes has provided us with a quick list of points to consider when breeding ewe lambs. Continue reading

Out-of-Season Lambing

James Thompson, Oregon State University, Retired Sheep Specialist
(Previously published on the Oregon State University Extension page: August, 2018)

Fall or out-of-season lambing involves breeding ewes in April and May to produce lambs in September and October. The inability of most breeds of sheep to cycle and breed in the spring to early summer is a major constraint for success in this endeavor. Despite this fact there are producers that are successful in getting a high proportion of their ewes to lamb in the fall. Some of the benefits for attempting to have ewes lamb in the fall include:

  1. Forage availability for ewes in early lactation;
  2. Weather conditions are ideal for pasture lambing; and
  3. Lambs born at this time of the year hit market weights when supplies are low and generally sell for a higher price.

Continue reading

Ram Behavior

Jackie Lee, 2019 DVM Candidate, The Ohio State University College of Veterinary Medicine

(Image Source: Stonehaven Farm)

We have all heard the stories of shepherds who have been injured or even killed by rams unexpectedly. The best way to avoid these situations is to prevent them. Knowing normal ram behavior, what promotes ram aggression and methods to mitigate aggression will facilitate producer safety. As a brief aside, there were very few scientific and text resources that impart advice on ram safety and incident prevention, therefore much of this article is attributed to the personal experiences and opinions of myself as well as my colleagues and mentors.

Rams have many typical behaviors that most producers are Continue reading

Summer Management of Replacement Ewe Lambs

Dr. Scott P. Greiner, Professor and Extension Animal Scientist, Beef/Sheep, Department of Animal & Poultry Sciences, Virginia Tech
(Previously published with Premier1Supplies)

Successful development,breeding, and lambing of ewe lambs is one of most important tasks of the shepherd. Summer is a critical time for the development of replacement ewe lambs as they make the transition from weaning to members of the breeding flock. Proper management of replacement ewe lambs during this time is critical to their future productivity and profitability.

In most breeding systems, replacement ewe lambs will be generated from within the flock. Therefore, attention to maternal traits in the rams siring potential replacements is critical. Additionally, preference should be given to crossbred ewe lambs. Crossbred animals have two major advantages over straightbred animals: 1) Crossbred animals exhibit heterosis (hybrid vigor), and 2) Crossbred animals combine the strengths of the breeds used to form the cross (breed complementarity). Crossbred females are superior to straightbreds for reproductive performance due to advantages received from heterosis. Crossbred ewes exhibit significant advantages Continue reading

Nutritional Flushing of Small Ruminants – Preparing for Fall Breeding

Washington State University Extension, Animal Agriculture
(Previously published on the WSU Extension Animal Agriculture page)

Introduction
Flushing isn’t just an aspect of indoor plumbing—it’s also part of a well-managed flock’s nutrition and reproduction program. This article will address the why’s and how’s of flushing sheep and goats.

Flushing Defined
What is flushing, anyway? The term describes a temporary but purposeful elevation in the plane of nutrition around breeding time. Its objective is to boost ovulation, conception, and embryo implantation rates. Flushing may also increase the proportion of females that exhibit estrus. Boosting these rates increases lambing and kidding rates by Continue reading

Buying Rams, What are You Really Getting?

Rodney Kott, Extension Sheep Specialist, Montana State University
(Previously published on the Montana State University Animal and Range Sciences Extension Service page)

For those of you with lambs in the barn, are you happy with your lamb crop so far? Did you happen to use a new breeding ram this year? If so, what type of selection criteria did you use to select this ram? As we begin to think about the next breeding season, Rodney Kott provides us with some food for thought to use in selecting our next breeding ram.

Buying rams… Are we really getting what we see, or are we just getting a new coat of paint?

Commercial sheep producers sell their grass and labor in the form of lamb and wool. The value of saleable product produced on a given land area is a function of the quantity and quality of lamb and wool. Production efficiency and ewe profitability can be maximized by Continue reading

Breeding for Out-of-season Lambs to Fill in the Industry Gaps

Brady Campbell, Program Coordinator, OSU Sheep Team

A few months ago as a part of the ‘Let’s Grow’ initiative sponsored by the American Sheep Industry Association, Dr. Reid Redden, Sheep and Goat Specialist with Texas A&M AgriLife Extension, presented a webinar focusing on the seasonality of the US lamb industry. This webinar was an overview of the recently published industry white paper that can be viewed fully by viewing this link. During his presentation, Dr. Redden covered both Traditional and Non-traditional markets that US producers have access to. He also presented several figures that outlined the time of year that lamb is most commonly consumed as well as when each specific cut of lamb is consumed. Rather than focusing on these highlights from Dr. Redden’s presentation, toady we will be focusing in on the production aspects of aseasonal or out-of-season breeding.

According to a 2011 USDA report, approximately 85% of all US lamb is produced Continue reading

To Breed or Not to Breed

Susan Schoenian, Sheep & Goat Specialist, University of Maryland Small Ruminant Extension Program
(Previously published on the Maryland Small Ruminant Page)

Breeding ewe lambs and doelings.

Should ewe lambs and doelings be bred to produce their first offspring when they are approximately one year of age? Or should you wait until they are yearlings to breed them for the first time? The answer depends. There are many factors to consider and there are pros and cons to each breeding decision.

Breeding ewe lambs and doe kids allows you to exploit their reproductive and genetic potential. It is well-documented that ewes that are mated as lambs will have a higher lifetime production than ewes that are mated for the first time as yearlings.

One of the most compelling reasons to consider breeding ewe lambs and doe kids is Continue reading

Understanding Fall Lambing

Dr. Christopher Schauer, Director and Animal Scientist, NDSU Hettinger Research Extension Center
Dr. Reid Redden, Extension Sheep and Goat Specialist, Texas A&M
(Previously published online with Extension)

(Image Source: North Dakota State University)

Fall lambing is a technique that can be utilized to capture additional productivity from many of today’s sheep breeds. Fall lambing has many positive attributes, including but not limited to, increased utilization of facilities and other resources, accelerated returns on animal investments, provide year-round supply of lamb, and provide options to lambing outside winter and spring months. The two negatives of fall lambing are lower conception rates and fewer lambs born per ewe lambing.

Most sheep will stop cycling when days start getting longer (Jan/Feb) and return to cyclicity when days start getting shorter (Aug/Sept). However, some breeds with naturally long breeding seasons (6-8 months), such as Dorset, Polypay, Rambouillet, Targhee, Katahdin, and Finnsheep, start cycling sooner and adapt to fall lambing with more success than short length breeding seasons (4 months) breeds. Selecting replacements from dams that have proven records of fall lambing will Continue reading

Ram Health: Pizzle Rot

Dr. John Martin, Veterinary Scientist, Sheep, Goat and Swine/OMAFRA
(Previously published on Ontario, Ministry of Agriculture, Food and Rural Affairs)

(Image Source: Renn-vue Farms)

Pizzle Rot in Sheep

To deal with the cause first. Like many conditions we see in sheep, pizzle rot is the result of an interaction between a bacteria and some other factor. The bacteria is Corynebacterium renale or one of that group. These bacteria have the ability to break urea down using an enzyme, urease. The other factor is an increase in the protein level of the diet, quite common in the month before breeding to improve the condition of the rams. Once the protein in the diet from all sources rises above 16%, urine can contain more than 4% urea. This excess urea makes the urine alkaline. The bacterial urease breaks down the urea to release excess ammonia. It is this ammonia that causes a severe irritation and ulceration of the skin around the preputial opening. Once the skin is ulcerated, C. renale or other bacteria will infect it. The debris Continue reading

There’s No Joke about Using a Teaser Ram

Brady Campbell, Program Coordinator, OSU Sheep Team

As many producers are in the midst of preparing for the upcoming breeding season, there are many tasks that need to be completed before turning the rams in. Of course, decisions need to be made regarding mating pairs and when to start flushing the ewes, but in this process have you ever considered “jump starting” the cycling of your flock in preparation for breeding. With this, I have a few questions that I have to ask many of you. Have you ever introduced a teaser ram to allow your ewes start cycling and to shorten the breeding season? If you answered no to both of these questions, I’ll ask, why not? Continue reading

How are You Preparing for Breeding Season?

Melanie Barkley, Livestock Extension Educator, Penn State Extension
(previously published on the Penn State Extension, Animals and Livestock page)

(Image Source: Premier 1 Supplies)

Throughout the year you make decisions to support or improve performance, but are there areas in your operation where you are overlooking some lost opportunities? Lost opportunities are those areas that could be tweaked to further improve production or performance. Let’s take a look at the breeding season to determine if there are opportunities to improve performance in that area.

A large factor that affects profitability in a sheep operation is the lamb crop. This involves anything from birth weights to growth to efficiency. Breeding season is a critical time so that we insure not only that ewes get pregnant, but that they also produce twins. We not only want high conception rates, but those conception rates need to be high during the first heat cycle.

Prior to breeding season, rams should be Continue reading

Webinar: Replacement Ewe Selection and Culling of Underperforming Ewes

Brady Campbell, Program Coordinator, OSU Sheep Team

Last Tuesday evening, Susan Schoenian, Sheep and Goat Specialist from the University of Maryland Extension, presented a webinar entitled: Replacement Ewe Selection and Culling of Underperforming Ewes. The webinar was sponsored by the Let’s Grow Committee of the American Sheep Industry Association.

Susan has been with Maryland extension since 1988 and is a sheep producer herself. Susan emphasizes that it is the ewe that makes the money on an operation and therefore it is critical to assess the selection and culling criteria of your flock. Selection of the highest quality females is important in securing a progressive flock. She also expresses that any ewe that fails to raise a lamb (i.e. failure to conceive or does not raise the lamb) should be culled from the flock regardless of her status. To listen to Susan’s seminar, please follow the link provided below.

Replacement Ewe Selection and Culling Underperforming Ewes

Ram Management

Tim Barnes, OSU Extension Educator, Marion County

(Image source: Shearwell Data – marking harness)

To achieve maximal fertility, rams should be physically examined for reproductive fitness to detect abnormalities that may affect breeding performance.  A breeding soundness examination can be completed before breeding season.  The scrotum and its contents as well as the penis and prepuce must be carefully examined.  The size and symmetry of both testes and epididymides should be assessed, and both testes should be firmly palpated for consistency and resilience. Semen can be collected and evaluated to check potential sires, particularly in ram lambs.  All screening procedures should be done Continue reading

CIDRs Now Officially Approved for Sheep

FDA Announces the Approval of a New Product for the Management of Reproduction in Sheep
November 16, 2009

The Food and Drug Administration (FDA) today is announcing the approval of EAZI-Breed CIDR Sheep Insert (progesterone solid matrix) for induction of estrus in ewes (sheep) during seasonal anestrus. This progesterone Continue reading

Breeding Season Preparation

Rory Lewandowski, OSU Extension Educator, Athens County

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