Cow’s Mothering Rating

Cow’s Mothering Rating

Posted July 28th, 2018 — Filed in Stockmanship

I have been following a thread on another e-mail list comparing the mothering rating of the cow that tries to attack anyone who gets close to their new-born calf as opposed to the cow that is OK with this. The consensus seems to be that the mellow cow is not as good mother as the cow that will try to eat you. I disagree with this.

Bud and I found that when you work livestock properly – that is, by using pressure/release methods instead of force and fear, the cows learn to respect but not fear you.  Since they don’t feel you are a threat to them, they also don’t think you are a threat to their calf so they don’t “get on the fight” when you need to handle their new baby.

When we lived in Canada we were involved with a Beef Booster cow herd.  In case you aren’t familiar, this is a composite breed.  Some of the herds were rated “Maternal.” Their main function was to produce heifers to go into the cow herd, another raised “Terminal bulls” to use on the herds that would market all of their calves, etc.  The man we worked for had about 100 head of cows that were designed to raise “Terminal bulls.”  He wanted to change over to a “Maternal” herd so he swapped his herd with a neighbor.  When these cows were delivered the neighbor also delivered a list of ear-tag numbers of cows that would kill you if you tried to handle their baby calf.   The only way they could weigh and tag the calf was with a bucket loader on a tractor.  A man in the bucket would get the calf, then the tractor operator would try to raise the bucket before the cow could climb in, too.  We received these cows in October.  We handled them quite a lot.  If the feedlot shipped a pen of cattle and there was still feed in the bunks, we’d put these cows in the pen for a while to let them clean the bunk.  Through the winter we tried to move their straw bed every few days to make it easier when they farmed the ground in the spring.  This usually meant we had to drive the cows to the new bed a couple of times to discourage them from going back to the old one, etc.  When spring came the owner was able to weigh and tag every calf with no aggression from any of the cows.

The first year we worked on the elk ranch In Texas, we didn’t see an elk calf until it was a couple of weeks old.  The following year, the cow elk would bring their newborn calves with them when we drove through the pasture, scattering hay.  We even had one calf born in the corral.

Meeting Your Goals

Selecting Bulls to Meet Your Goals –

By Kit Pharo

I came across an internet article late last week entitled, “Selecting Bulls to Meet Your Goals,” or something like that.   It wasn’t worth the time it took to open the link – but it did get me to thinking.   I suspect most cow-calf producers have no goals.   They are just doing what everyone else is doing and/or what they have always done.   If you don’t have goals, you have no direction in your life or business.

Do you have business goals?   I’m not talking about ideas or dreams you think about every now and then.   I’m talking about real goals.   If you have real goals, you are probably one in a thousand.   If you have real goals, you have a HUGEcompetitive advantage over everyone else in your business.   If you have real goals, you are creating your own future.   If you have real goals, you are also creating a future for the next generation.

A real goal must be Specific, Measurable, Attainable and Time-Sensitive.

  1. Specific: Goals are no place to waffle.   This is no place to be vague.   Vague goals produce vague results.
  2. Measurable: Always set goals that are measurable.   If they are not measurable, you will never know for sure when they have been achieved.   For example, don’t set a goal to “make more money.”
  3. Attainable: Goals must be realistic and attainable.   Most people don’t set goals – so when they do, they tend to set goals that are too big to be easily attained.   This creates discouraging results.
  4. Time-Sensitive: Every goal should have a timeframe attached to it.   A goal must have a deadline – a time in which you want to accomplish it.

I have achieved the best results when I break my big goals down into several (or many) smaller goals that can be easily attained in a relatively short period of time.   I liken my really big goals to an elephant that must be eaten.   There is no way I can eat an elephant in one sitting.   However, I will eventually eat the entire elephant – one bite at a time.

If you do not have any business goals, I encourage you to set some.   Start out by just setting one simple goal that should be easy to attain.   Do it today!   Someday is not a day of the week.   I cannot think of anything that will even come close to giving you a greater return on the time invested.   You will literally amaze yourself!

Let’s go back to the subject of bull selection…

Since the bulls you purchase are responsible for at least 90% of your herd improvement (or deterioration), it makes sense that bull selection can play an extremely important part in helping you meet your goals.   Are you purchasing bulls that will help you achieve your business goals?   Are you purchasing bulls that will increase your future success and happiness?   Are you purchasing bulls with the next generation in mind?

Quote Worth Re-Quoting –

“Setting goals is the first step in turning the invisible into the visible.”   ~ Tony Robbins

Extension / Publications / Bull Buyer’s Guide

Never underestimate the power of your bull. Selecting and purchasing a bull for your beef herd could be considered one of the most important decisions you make in your operation. Don’t make a quick, unprepared decision on purchasing a bull. Never consider purchasing a bull without a proven record and a sound genetic background. Using a bull with poor performance and a weak genetic base could delay improvements in your herd for several years. The small expense you have in purchasing a bull is the difference between the purchase price of the new bull and the salvage value of the old bull (see Example 1). This investment will add efficiency and profitability to your herd for years to come.

Example 1. Cost of a bull purchase

 

$3000 Purchase Price of New Bull
-2090 Salvage Value of Old Bull (1900 lbs. X 1.10/lb.)
$ 910 Net Cost of New Bull

If the new bull sires 90 calves over the next 3-5 years, $910 ÷ 90 = $10.11 cost/ calf. If the bull sires 90 calves that are 10 pounds heavier at weaning and they sell for $1.09/lb. (3-year average for 500-pound calves ? GA Auction Markets, 2009-2011) at weaning, you will have paid for the bull.

The cost of purchasing a bull may seem high at a glance; however, that expense becomes relatively small when it is spread across your bull?s calf crop for a three- to five-year period. Example 1 shows how you can turn an expense into a savings. Bull procurement decisions can greatly impact your future calf crops and herd genetics for many years. When you consider that the bull contributes one-half of the genetic makeup of your calf crop and may sire 25 to 40 or more calves per year, it is easy to see that he is the most important individual in the herd. Keep in mind that a bull that will improve a herd must have genetic superiority over both the cows in the herd and over pervious bulls.

The best way to remain efficient in today’s beef industry is continue to produce more pounds of product per cow exposed. That task can become hard to achieve without the help of a superior bull. Fortunately, weight at various ages is heritable. Birth weight and weaning weight are estimated to be about 30 percent heritable, while yearling weight is about 45 percent heritable. This means that a certain degree of birth weight, weaning weight and yearling weight is inherited from the parents and that progress can be made by selecting for these traits.

Selection Tools

Birth, weaning and yearling weights are normally used to evaluate breeding animals. Actual or adjusted weights may help in making comparisons between bulls in the same contemporary group (a group of animals from the same herd, year and season that is raised together under the same conditions). Since environmental factors like feed and weather affect weights, actual or adjusted weight can be misleading if bulls come from different contemporary groups. Within a herd, weight ratios help account for some of the environmental differences between contemporary groups. But, ratios can also be misleading if bulls come from different herds. Expected Progeny Differences (EPDs), on the other hand, are calculated across herds. A bull’s EPD for a trait is a more accurate estimate of his genetic worth than his weight, adjusted weight or ratio. EPDs not only account for contemporary group and herd differences, they also include information on a bull?s relatives as well as his individual performance. Breed associations report EPDs on weights and many other traits.

Most major breed associations have National Cattle Evaluation programs. Breeders who are involved in their breed’s performance program should have birth, weaning and yearling weight EPDs available on yearling bulls. In all of these breeds, weight EPDs are expressed in pounds of calf. For example, if bull A has a weaning weight EPD of +45 and bull B has a weaning weight EPD of +35, the calves produced by bull A are expected to weigh, on the average, 10 pounds more at weaning than those of bull B, assuming the bulls are bred to comparable cows.

Advances in National Cattle Evaluation have made estimating a bull’s genetic worth more accurate than ever before. EPDs allow valid comparisons of all bulls of the same breed, but they do not allow comparison of bulls from different breeds. Since breeds have different average performance, base years and evaluation procedures, direct comparison of EPDs from different breeds can be extremely misleading. It should also be noted that a bull with an EPD of zero is rarely average. In most breeds, zero is the average of some base group of animals. Since breeds change over time, in some breeds it is possible to find bulls with positive weaning and yearling weight EPDs that are several pounds below the average of all yearling bulls in that breed. Current breed averages and information on how to use EPDs are included in breed association sire summaries, which are available on most major breed association websites.

Accuracy Values (ACC) are usually published with EPDs. The accuracy values indicate the reliability of the EPD, or how likely the EPD is to change as more information becomes available. Accuracies are usually expressed as correlations ranging from zero to one. The closer the accuracy is to one, the more reliable the EPD is. Yearling bulls normally have low accuracy values. Older AI sires can have very high accuracies.

Recommended Performance Standards

Weaning Weight ? Yearling Weight

Commercial producers are paid for pounds of calf. Two very important traits to consider are weaning and yearling weights. However, single trait selection may result in problems with other traits. A good example is selecting for yearling weight alone, which results in increased birth weight because the two traits are genetically correlated. Select bulls that have an excellent combination of performance EPDs that are at or near the bulls’ breed average. Desired genetic improvement involves a combination of several traits, including weaning and yearling weights.

Milk Production

Maternal ability within a breed can best be evaluated with milk EPDs; however, milk is not measured directly in beef cattle performance programs. It is measured in terms of how it affects weaning weight. Milk EPD on a bull is an estimate of pounds of calf at weaning produced by the bull’s daughter due to her milking ability. For example, if bull A has a milk EPD of +5 and bull B has a milk EPD of +2, all other things being equal, bull A’s daughters should produce calves that wean 3 pounds heavier than those from daughters of bull B due to extra milk production. There is some variation in the terminology used by different breed associations in reporting maternal EPDs. An explanation of maternal EPDs is included in a breed’s sire summary.

Producing extra milk requires that a cow consumes extra protein and energy. High milk production can affect a cow’s ability to breed back after calving. For this reason, selecting for maximum milk production is not a good idea in most commercial herds.

Conformation

The cattle industry produces cattle of all breeds, sizes, ages and quality. There is a market for all of them. However, if you sell feeder calves or feed out your own cattle, consider the following points:

  • Good quality cattle eat no more feed than low quality cattle and are just as efficient at converting feed to beef.
  • Bulls should generally have a muscling score of one and be medium plus to large minus framed, according to the USDA feeder calf standards (Table 1). Such calves will bring a higher price than lower grade calves.
  • Low quality cattle with poor conformation usually are more subject to price declines in years of over production than are high quality cattle. Small framed cattle mature early and are slow, inefficient gainers if fed past maturity.

Frame Score

Hip height in inches is used to give an indication of frame size. Most bull test stations and a large percentage of purebred breeders will have a yearling hip height for each animal. Table 1 gives the ranges of hip height as they relate to mature frame size. Remember, taller cattle do not necessarily grow faster or more efficiently, but they do have a later maturity pattern. Small-framed cattle are discounted in Georgia markets. A bull needs to have enough frame to produce calves that are at least USDA Medium.

Table 1. Hip height relative to mature frame size

 

USDA Frame
Small Medium Large
Frame score 1 2 3 4 5 6 7
7-month hip height (in) 36 38 40 42 44 46 48
12-month hip height (in) 41 43 45 47 49 51 53
Potential slaughter weight 800 900 1000 1100 1200 1300 1350+

Birth Weight

First calf heifers have the most calving problems, so buying a bull with a low birth weight EPD is extremely important when the bull is to be used on heifers. Birth weight is the single most important trait that influences calving difficulty. While many cattlemen look at actual birth weights on bulls, birth weight EPDs are the most accurate measure of a bull?s potential calving ease.

Many breeds report Calving Ease EPDs that are calculated using birth weight and calving scores. These can also be helpful in selecting bulls. Refer to the breed association?s sire summary for a description of how these are reported for a particular breed.

Scrotal Circumference

Research indicates that yearling bulls with large testicles sire daughters that show estrus at an earlier age than bulls with smaller testicles. Be sure the bull you select has a scrotal circumference that is at least 30 cm at 1 year of age.

Physical and Semen Evaluation

If the bull you are considering buying is 12 months or older ask for a physical and semen examination. This can be done by the local veterinarian and will increase your confidence that the bull will be able to settle cows.

Other Traits

Breed associations report EPDs for many other traits and this large volume of information can be overwhelming to the bull buyer, so focus on the basics listed above. You do not have to understand every aspect to be able to select a good commercial bull. When you become comfortable with the basics, consult the breed association website for updates on the most recent developments.

How Much “Bull-Power” Do I Need?

Several factors can help determine the number of cows that can be bred to one bull.

Age

The number of cows per bull will vary with the bull’s age, condition and libido. Use an adequate number of bulls with good libidos. Bulls should be in good body condition, but not fat, at the beginning of the breeding season. Young, growing bulls may require extra feed during the breeding season to meet their protein and energy needs. A yearling bull should not be expected to breed more than 20 to 25 cows, while a mature bull with large testicles, good semen and good libido can breed 25 to 40 or more cows.

Condition

You cannot expect fat or thin bulls to perform up to the standards of properly conditioned bulls. Poor nutrition can influence semen quality. Fat bulls lack the stamina to breed enough cows.

Length of Breeding Season

Length of the calving season and number of calves born during each 21 day period of the calving season does have some influence on the number of cows that can be bred to one bull. Mature bulls can breed up to 40 cows during a 60- to 90-day breeding period and sire a high percentage of these calves in the first 40 days of the calving season. If cows are run in large groups, two bulls that are the same age and breed could run with 80 cows.

Breeding Systems

An artificial insemination (AI) program will not require as many bulls, but the quality of the bulls turned out after the AI period needs to be very high to ensure against poorer quality calves than the AI sired calves. Have a short AI program, no longer than 40 days, and then turn out the cleanup bulls.

Other Factors to Consider when Buying a Bull

  • The bull you buy should be functionally sound — a good breeder with a long life ahead — and he should be structurally correct, with sound feet and legs and strong pasterns.
  • The bull should not have swollen joints and should be able to move freely and easily.
  • The bull should not be extremely nervous. A bull with a mean disposition is difficult to handle and he may pass on his nervousness to his offspring.

Be sure you do not buy disease when you buy a bull. Request a copy of the bull’s health record. Place new bulls in an isolation paddock where you can observe them for 30 days before putting them with the herd.

Where to Buy a Bull

Many top cattlemen think where to buy a bull is the most important choice involved in their purchase. You need to know that records of birth dates, rate of gain, weaning weights and health conditions of a bull are just as the seller says. You need to know that the breeder will live up to his responsibilities. It has been said that records and pedigrees are as good or as poor as the integrity of the breeder. Here are some recommendations:

  • Buy from a breeder whose integrity is above reproach.
  • Buy from someone who has complete performance records on his cattle, and knows what those records mean.
  • Buy from a place where you know the type of management under which the bulls were produced.
  • Buy bulls from central test stations where all records are available.
  • Buy bulls from performance oriented producer sales.
  • Buy bulls from breed association sponsored sales.

Using Artificial Insemination

Artificial insemination increases your chances of promoting the important traits. Since many of the bulls in the AI studs have a great number of progeny with performance records, you can predict more accurately what their calves’ performances will be in your herd. AI services also screen their bulls closely for any undesirable traits.

Whether you breed your cows by AI or not is a decision you must make based on your own labor and management situation. However, you can consider AI as one method of “buying a bull.”

Selecting a Bull for Crossbreeding

It is just as important to select bulls for a crossbreeding program based on traits that are heritable as it is for other breeding systems. You can improve your herd by careful selection and produce hybrid vigor at the same time.

Determining a Bull’s Worth

It is very difficult to predict the dollar value of a particular bull; however, the following factors can affect a bull’s value:

  • The number of calves the bull may sire.
  • The performance level of the herd on which the bull is to be used. Almost any good bull will improve the performance of a poor herd, while only very superior bulls can help a high performing herd.
  • The type of breeding system you select. Purebred breeders can usually justify a higher bull investment than can commercial producers.

Summary

Selecting and buying a herd bull is the quickest way to make genetic improvement in your herd. The selection process must include looking for those traits that are economically important and highly heritable. Your own herd records are necessary if you are to select a bull that will improve your genetic base. Demand and buy bulls with total performance that will improve your herd.


Status and Revision History
Published on Jul 01, 1994
In Review on Feb 03, 2009
In Review for Major Revisions on Feb 03, 2009
Unpublished/Removed on Jul 03, 2012
Published with Minor Revisions on Jul 25, 2012
Published with Full Review on Mar 31, 2017

Bull Buyer’s Guide: Beef2Live.com

Are you sifting through stacks of bull sale catalogs looking for your next bull? While bull selection can be a daunting task, your choice will impact your herd for years to come. Thus, taking some time to think about what you need from your next herd sire is important.

Here are some points to emphasize when it comes to bull selection.

Know your market. Understand what traits are value added-traits for your market. One of the best parts about the cattle industry is the different ways producers achieve their goals. While selling calves at weaning into the commodity market is the majority, some cattlemen are marketing in very creative ways. Local freezer beef, retained ownership, alliances, branded beef programs, video sales, or fitting the production environment to a consumer demanded practice are all ways farmers are adding value to their calves. Your bull selection should be based on traits that are profitable in your market.

Don’t sacrifice functional traits or adaptability to your production environment. It is really easy to get caught up in the data, but remember these critters need to be sound and function in the pasture. Good feet and legs, a strong libido, and docility are all imperative. Masculinity, big testicles, and a tight sheath are good phenotypic indicators of the right kind. Buying bulls that are raised in similar conditions to your farm is preferred. You can buy someone else’s genetics, but you can’t buy their management.

Require a passed BSE (Breeding Soundness Exam) and farm herd health protocols. I also suggest a quarantine period for new purchases. A minimum of two weeks will allow time for potential pathagens to break without exposing your herd. Lots of times cattle coming from a sale have experienced elevated stress. It is important to keep them on good feed, in a clean pen, and allow the quarantine period to run its course.

Identify and understand Expected Progeny Differences (EPDs) and phenotypes that signify value added traits you are seeking. Calving ease (CE) is an important and valuable trait. Sometimes when talking to producers I hear them stressing CE and birth weight (BW). BW is an indicator trait for CE, but you don’t get paid for light birth weight calves. You get paid by not having to invest time and labor in pulling calves. So, avoid putting too much downward pressure on BW, especially if the bull will breed cows. Another mistake I see is purchasing low BW bulls for cows. This is not necessary. Many times you can purchase a bull with average or better calving ease for cows at a discount to “heifer bulls” with comparable growth. Smooth, flat shouldered bulls with decent CE EPDs are good value bulls for breeding mature cows.

If you sell your calves at weaning through the salebarn and keep your own replacements, traits of priority should be CE, heifer pregnancy, stayability, and weaning weight. Selecting for more yearling weight, too much milk or too little milk, or cacarss traits are much less important in this scenerio. If you retain-ownership in you cattle through the feedlot and market to the packer, then yearling weight and carcass traits become more relevant to your bottom line. Your ultimate goal should be to produce the most profitable product, thus seek traits that add value without increasing cost of production over the value of the trait.

Utilize appropriate multiple trait selection indexes. Find the sweet spot/ profitable window in milk, YW, and carcass EPDs. Avoid putting too much emphasis on one trait. Nearly all breeds now have dollar index values that help put economics to trait selection. These can be extremely effective tools if the index scenario matches your operation. Weaned Calf Value ($W) is a dollar value used by the Angus breed. It is an index that is designed for cattlemen that primarily sell calves at weaning. This index also assumes that replacement heifers are retained. EPDs for birth weight, weaning weight, milk, and mature cow size are focused on. Lower birth weights, heavier weaning weights, and lower mature cow size are desirable. Milk production is weighted both positively and negatively as it directly impacts calf weaning weights, but also increases cow maintenance requirements. A more detailed description of economic selection indexes is available on my blog

Don’t be fooled by index names. Beef Value ($B) is a terminal index. It is a great tool for cattlemen that are not keeping replacements. This index will increase profitability of cattle in the feedlot and on the grid. Unfortunately, I have heard $B referred to as a comprehensive EPD several times which it is not. It is vital to understand that $B is a terminal index. Don’t be afraid to ask questions. The breeder or an Extension specialist will be able to help explain the numbers.

Demand higher accuracy for traits. Technologies are available for seedstock producers to increase the accuracy of EPDs on yearling bulls. Genomic-enhanced EPDs result in less risk, less change, and more predictability in how a yearling bull will sire. A bull buyer can feel more confident now than ever in EPDs when they are backed by genomic testing.

Heterosis. Crossbreeding systems are hard to deploy and maintain in small herds. However, leaving hybrid vigor on the table in a commercial herd is a big loss. Otherwise lowly heritable traits like reproduction, health, and cow longevity are best improved by crossbreeding. Crossbred cows and maternal heterosis is a key to profitability on commercial cow/calf operations. Studies have shown net profit per cow is increased by $75/cow/year as a result of maternal heterosis.

Buy the right size, type, and demand quality. I would compare this to buying a car or truck. If you have little money for gas (feed), then don’t buy a gas (feed) guzzler. Buy a bull that fits your cow herd. Your cows will tell you the right size and milk production for your management. If they come up open… they are not the right size. Now, you also want a bull that is the right type. You don’t buy a fancy sports car for a work vehicle do you? So why buy a fancy, sexy bull to produce working kind cattle? To me there is a difference in fancy and quality. I suggest you demand quality. Select a product that will last and hold value. Look for signs that the breeder stands behind their product. That is a good sign of quality.

Seek value when buying a bull. The lowest priced bull is seldom the best valued. If you find a bull that has the traits you are looking for… buy him. Set a budget, but understand it is often hard to find everything you are looking for. Bulls with the traits you are seeking can add value to your cattle in a hurry. They can add far more value than a cow. The bull you buy this year will impact your herd for the next 5 years with his calves, but his daughters will impact your herd for the next 20 years. Make a good investment. Buy a bull that adds value to your calves and your cowherd.

Written by Travis Meteer, Extension Educator, Commercial Ag, University of Illinois, and used with permission.

Bull Selection: Using Economically Relevant Traits

Beef Cattle Research Council www.BeefResearch.ca.

Sire selection often encompass a variety of factors such as how well a bull fits into the breeding objectives of your operation, breed, conformation, pedigree, birthweight, and price. Recent surveys from western Canada in 2014 and 2017, Ontario in 2015/16, northern Ontario and Quebec in 2015/16, and Atlantic Canada in 2016/17 production years asked respondents to rank their top bull selection criteria.  There wasn’t a lot of variation between regions with breed, conformation, pedigree, birth weight, individual performance, expected progeny differences (EPDs), and temperament all being highly ranked by survey participants.   

Some of the criteria, like breed, may influence sire selection due to the desire to capture heterosis or breed complementarity effects.  Conformation is important for longevity and ensuring the bull gets the job done during the breeding season.  Having a bull with a desirable temperament makes everyone’s lives easier, especially if there are children or older individuals involved in the operation.  Individual performance and birth weight may give some indication of how the bull’s progeny may perform, but a better indicator in this area is actually the bull’s EPDs. Response to selection using EPDs is 7-9 times more effective than selecting based on individual animal performance7.

The question is, how well do these various selection criteria translate into profit?

Answering this question means taking a look at your operation.

  • What are your breeding/marketing goals?
  • Which traits affect the profitability of your operation?
  • What constraints does your operation have (forage resources, labour, etc.)?
  • Do you raise your own replacements or purchase them4?

Once those questions are answered, there are likely a number of traits you have identified as important to your operation.

While a number of data sources exist to help you evaluate the contribution of a potential herd sire to improving the traits of interest, it is important to recognize whether the traits you have identified are indicator or economically relevant traits.  Good record keeping is crucial to determine whether or not progress is being made in the traits you have identified as important to your operation’s productivity and profitability.

Economically relevant traits (ERTs) are those that are directly associated with a source of revenue, or a cost.  Not all EPDs represent ERTs – instead they use a related (or indicator) trait to estimate the ERT.

One of the best examples is birth weight.  Decreasing a bull’s birth weight by 5 lbs does not have any associated income or costs, but is often used as a bull buying criteria in an effort to reduce calving problems.

The actual ERT in this case is calving ease, as an increase in calving problems will reduce calf survival (less calves to sell), incurs higher labour costs (pulling calves, or more time spent monitoring), and delays cow rebreeding (younger and lighter calves to sell next year).

Similarly, ultrasound for carcass traits is another suite of common indicator traits, while the ERTs are the actual carcass measurements (weight, yield, and marbling).

We all recognize fertility (in both sires and dams) as a trait that has the biggest impacts on profitability.  But fertility has relatively low heritability, meaning that cumulative environmental influences (e.g. nutrition, weather, etc.) generally have a larger impact than genetics.  In Canada, some genetic evaluations do not report any EPDs at all for ERTs related to female fertility. While most evaluations include scrotal circumference (indicator), it actually has a near zero relationship with heifer pregnancy rate (ERT)

In the Canadian context, a stayablity or length of productive life type of EPD (probability of an animal remaining in the herd for X period of time or awarding more credit to cows remaining longer in the herd), while an ERT itself, is also the best proxy for fertility given the lack of EPDs in this area, as the most common reason for a cow to be culled is because she’s open.

When EPDs for both indicator and ERTs for the same trait are included in genetic evaluations (e.g. calving ease and birth weight), make sure you focus on the EPD for the ERT and not the indicator trait. The indicator trait cannot add more information to the selection process, as it is already used in the calculation of the EPD for the ERT in the first place.  When an EPD for an indicator trait is available, but no EPD exists for the ERT (e.g. scrotal circumference and heifer pregnancy rate), it can result in an over or under-estimation of the ability of the indicator trait to predict the ERT3.

Given the plethora of EPDs available, trying to sort through ten or fifteen or twenty individual EPDs that may not have relevance to your particular operation can easily lead to information overload.  By focusing on the ERTs, you can eliminate those bits of information that will not directly impact your operation’s profitability.

For example, if you’re using a terminal system (not keeping replacements) and selling at weaning, the weaning weight EPD is going to be one of your most important ERTs.  If you tend to retain ownership through to slaughter, the more relevant ERTs are carcass weight, quality, and yield grades.

In some cases, whether a published EPD is an indicator or ERT will depend on how that EPD is reported.  For example, carcass trait EPDs calculated using combination of ultrasound and actual carcass data would be ERTs (e.g. marbling score), but those reported on an ultrasound data basis (e.g. percent intramuscular fat) would be indicators.  Table 1 contains some common traits that may or may not have a published EPD in your breed of choice and whether they are an indicator or ERT.

Table 1.  List of selected EPDs characterized as indicator or ERT

Adapted from (4) and (6) (see references below).  This is not an exhaustive list.

Many genetic evaluations offer selection indices in addition to individual EPDs.  These are calculated by placing an economic weighting on individual EPDs to create a multi-trait selection model for different types of broad production systems (generally maternal or terminal).  These provide a way to objectively categorize a set of animals using the same criteria throughout.  Examples include the Canadian Simmental Association’s All Purpose Index (API) and Terminal Index (TI), AgSight’s BIO$ Economic Index, or the Canadian Hereford Association’s Maternal Productivity Index (MPI) and Feedlot Merit Index (FPI).  The indices offered by most breed associations are fairly robust across production environments, keeping in mind their overall objective – don’t expect high ranking terminal index bulls to give you stellar replacement heifers.

Ideally, selection indices would be tailored to each individual operation’s identified ERTs, with different economic weightings depending on the production system, but the creation of customized selection indices with real-world economic weightings requires detailed cost and return information and a complete understanding of the complex genetic relationships between traits.  This type of model may also present some difficulty for seedstock producers, as marketing based on a fluid index (where a bull could be in the top 1% for X trait in one type of production system, but only in the top 50% for the same trait in another production system) would be challenging.4

Regardless, the amount of detailed information required to populate these types of models may not be readily available for the average producer.

By identifying ERTs, you can narrow your selection focus to the EPDs that matter most for your breeding goals, increasing the likelihood that the decisions you make will actually have an impact on your bottom line.

Editor’s note: Stay tuned for part four in this four-part series. (See part one and part two).

1Ahlberg, C.M., L.A. Kuehn, R.M. Thallman, S.D. Kachman, and M.L. Spangler. 2014. Genetic parameter estimates for calving difficulty and birth weight in a multi-breed population. In Proc. 10th World Congress on Genetics Applied to Livestock Production.

2Bennett, G. L., and K. E. Gregory. 2001. Genetic (co)variances for calving difficulty score in composite and parental populations of beef cattle: I. Calving difficulty score, birth weight, weaning weight, and postweaning gain. J. Anim. Sci. 79:45-51.

3Golden, B.L., D.J. Garrick, S. Newman, and R.M. Enns. 2000. Economically Relevant Traits: A framework for the next generation of EPDs. Proceedings of the 32nd
Research Symposium and Annual Meeting of the Beef Improvement Federation. Pp. 2-13

4Spangler, M.L. 2015.  Economically relevant traits and selection indices.  Range Beef Cow Symposium XXIV.

5Spangler, M.L. 2017.  Economically relevant traits.  Accessed Online at: https://beef.unl.edu/economically-relevant-traits

6Enns, R.M. 2010.  National Beef Cattle Evaluation Consortium Beef Sire Selection Manual 2nd Ed.  The Role of Economically Relevant and Indicator Traits.

7Spangler, M.L. and R.L. Weaber. 2017. Genetic Selection vs. Visual Appraisal: Is it a Conundrum?  Range Beef Cow Symposium XXV

Bull Selection: What are you looking for?

Editor’s note: The following is part two of a four-part series that will help you to evaluate different breeding programs, which bulls are optimal for your herd, and how much they’re worth. (Seepart one).

Bull selection is one of the most important decisions for cow-calf producers, with implications for short- and long-term profitability of the operation. The choice of bull can be immediately seen in the subsequent calf crop.

If the operation retains heifers and/or bulls, the genetics in the selected bull will be passed down to subsequent generations. Introducing new genetics is a permanent change to the herd, compared to the temporary nature of supplements or management practices. As such, bull selection can be seen as a long-term investment into the operation.

Research in the area of beef cattle genetics has been growing significantly. There are opportunities to improve profitability through sire selection. However, with a multitude of traits, breed differences, operational goals, and management practices, bull selection is a complex decision.

There are a range of different beef operations in Canada, and there is no one type of bull that is optimal for all operations. Bull selection depends on many factors such as management style, calving season, labour availability, age when calves are marketed, heifer retention practices, and nutritional management.

Before selecting a bull, operational goals should be established and the management and breeding practices (see Part 1) that fit those goals determined.

For example, a full-time producer who observes the cattle multiple times a day may not prioritize calving ease in a bull as much as an operation with limited labour. A farm with limited forage resources may prefer smaller cattle that are more efficient at converting low quality forage.

To assist with making bull selection decisions, consistent record keeping on the herd will help identify areas of strength and weakness in the herd and guide you towards the type of genetic change you want to see. Once operational goals and breeding programs have been determined a producer can focus in on specific Expected Progeny Differences (EPDs) to guide their bull selection.

When selecting a bull, Expected Progeny Differences (EPDs) are a helpful tool to predict bull performance. EPDs are the estimation of an animal genetic merit. They are compared to a breed average (not zero) and cannot be compared across breed. An explanation of EPDs can be found here and in NBCEC (2010).

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Table 2. Expected Progeny Difference (EPD) indicators by category

Calving ease is a key trait that influences profitability. It is estimated the majority of calf loss is a result of dystocia (difficulty calving). Dystocia results in higher labor costs, decreased calf survival, and delayed rebreeding for the cow resulting in younger calves at weaning the following year.

The EPD for calving ease takes into account numerous factors including birth weight. Studies suggest birth weight is the most important factor for calving ease – a one pound increase in birth weight increases the probability of dystocia by two percent (Herring, 1996). Birthweight, while important for calving ease, isn’t always a direct correlation, for example a larger frame score cow should have no problem giving birth to a 95 lb calf; whereas, a smaller frame score cow might, especially if that calf has a bigger head and shoulders. However, shoulder width and pelvic areas alone have not been shown to be useful predictors in calving ease (NBCEC, 2010). Purely focusing on low birth weights when selecting bulls can be ill-advised. As low birth weight is genetically correlated with weaning and yearling weights, such a breeding program may lead to lower growth performance (Herring, 1996).

“Labour availability, a high proportion of heifers, calving on pasture, or a new producer with limited time and experience, calving ease should be prioritized”

To determine the significance of calving ease in bull selection, the goals and type of the operation should be taken into consideration. For example, if there is low labour availability, a high proportion of heifers, calving on pasture, or a new producer with limited time and experience, calving ease should be prioritized. On the flip side, an intensive operation focused on selling large calves may not find calving ease to be as important. Calving ease may also be an important trait if calving in late winter (i.e., February), as cold weather has been linked to larger calves and lower calf survivability (Hamilton, 2010).

Other traits of interest are milk production and bull fertility.

High milk production results in increased weaning weights. However, it raises energy requirements for cows even when they are not lactating. If the cow-calf operation has low forage availability, selecting for high milk production may lead to feed shortages and undernourished cattle. If running a terminal system and not retaining any heifers, the milk production trait becomes less relevant.

Bull fertility is linked to higher semen quality and quantity, as well as a lower age of puberty for his daughters.

As already mentioned, there are potential trade-offs between birth weight and performance. A low birth weight may increase calving ease, but it is correlated with lower weaning weight. However, there are many cases where a low birth weight is warranted; for example, when labour availability is limited or when breeding heifers. A low birth weight can be compensated for by selecting for higher milk production; however, as milk production increases, the nutrient requirement of cows will also increase, although it’s not a direct 1:1 relationship. Selection for superior growth can lead to calving difficulty and cows too large for the existing forage resources.

When calves are marketed also affects bull selection. If calves are sold at weaning, producers can focus on traits associated with a higher weaning weight, such as milk production and weaning weight EPD. When ownership is retained, weaning weight is less of a priority, and the focus may shift to traits such as yearling weight and carcass indicators (e.g., carcass weight, ribeye area, fat thickness, marbling). EPDs can help remove some of the guessing game when it comes to carcass quality as visual appraisal of muscling does not have a strong link to carcass quality.

Bull conformation directly affects longevity, and his structural soundness is passed along to the cow herd. Conformation can be evaluated through visual appraisal. Key factors to look for are the bull’s ability to walk easily without discomfort, the slope and angle to the joints of the legs, free from defects of the claws (e.g. toes that cross over each other or turn up), and joints free of swelling and inflammation. Healthy legs and feet are particularly important for extensive operations and large pastures, especially if there is rough terrain or multiple bulls in a breeding field.

When looking at body condition, the goal is to choose a bull with a moderate score. If the score is low, the bull’s performance is reduced as they lose weight during the breeding season. If the body condition score is too high, sperm quality and stamina are adversely affected.

Temperament is another consideration for bull selection. Bulls that are aggressive, nervous, or flighty may be undesirable due to safety concerns (e.g. older operators or young children) or damage to facilities. On the other hand, as temperament is moderately heritable, overly docile cows can pose an issue if calving on pasture where predation is a concern.

There is no one-size-fits-all solution or a bull that is best for all scenarios, as the right genetics depend on the individual operation. Key EPDs include:

  • maternal and fertility traits (e.g. calving ease, milk production, bull fertility),
  • trade-offs between performance and carcass quality traits,
  • conformation and structural soundness.

For example, labour availability during calving season and how closely females are monitored will determine the emphasis on calving ease and birth weight EPDs when selecting a bull. Or if marketing calves at weaning or retaining ownership will influence trade-off producers are willing to live with. Is the higher birth weight and time spent at calving worthwhile come sale day when you see that weaning weight?

There are many different types of bulls available, and effective sire selection requires an understanding of the characteristics of the available genetics as well as your own operation. Deliberate alignment of the bull’s genetics to your operational goals will contribute to enhanced revenue and reduced costs.

Beef Improvement Federation (BIF) resources https://beefimprovement.org/library-2/fact-sheets

Kuehn, L. and M. Thallman. 2018 Across-Breed EPD Table and Improvements. Beef Improvement Federation (BIF) https://beefimprovement.org/wp-content/uploads/2019/01/18_ABEPDpressreleaseandfactsheet.pdf

Schmid, K. EPDs: What do all those numbers mean?http://www.beefresearch.ca/blog/epds/

National Beef Cattle Evaluation Consortium (NBCEC). (2010). Beef Sire Selection Manual 2nd Edition. http://www.nbcec.org/producers/sire_selection/manual.pdf

Gosey, J.A. (1991). Crossbreeding Systems and The Theory Behind Composite Breedshttp://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1235&context=rangebeefcowsymp

Weaber, R.L. (2015). Crossbreeding Strategies: Including Terminal Vs. Maternal Crosseshttp://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1331&context=rangebeefcowsymp

Agriculture Victoria (2017). Breeds of Beef Cattle. http://agriculture.vic.gov.au/agriculture/livestock/beef/breeds/breeds-of-beef-cattle Accessed January 16, 2019.

Evans, J. and McPeake, C.A. Crossbreeding Beef Cattle I. http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Rendition-2051/unknown Accessed January 20, 2019.

Gaines, J. A., McClure, W. H., Vogt, D. W., Carter, R. C., & Kincaid, C. M. (1966). Heterosis from crosses among British breeds of beef cattle: Fertility and calf performance to weaning. Journal of Animal Science 25(1): 5-13.

Gosey, J.A. (1991). Crossbreeding Systems and The Theory Behind Composite Breeds. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1235&context=rangebeefcowsympAccessed January 20, 2019.

Gregory, K. E., Cundiff, L. V., Koch, R. M., Laster, D. B., & Smith, G. M. (1978). Heterosis and Breed Maternal and Transmitted Effects in Beef Cattle I. Preweaning Traits 1, 2, 3, 6, 7. Journal of Animal Science 47(5), 1031-1041.

Hamilton, T. (2010). Summer Calving Can Be Super! http://www.omafra.gov.on.ca/english/livestock/beef/facts/info_summer_calving.htm Accessed January 20, 2019.

Herring, W.O. 1996. Calving Difficulty in Beef Cattle: BIF Fact Sheet. https://extension2.missouri.edu/g2035 Accessed January 20, 2019.

Koger, M. (1980). Effective crossbreeding systems utilizing Zebu cattle. Journal of Animal Science 50:1215.

MacNeil, M. D. (2009). Invited review: Research contributions from seventy-five years of breeding Line 1 Hereford cattle at Miles City, Montana. Journal of Animal Science 87(8): 2489-2501.

National Beef Cattle Evaluation Consortium (NBCEC). (2010). Beef Sire Selection Manual 2nd Edition. http://www.nbcec.org/producers/sire_selection/manual.pdf Accessed January 20, 2019.

Northcutt, S.L., Buchanan, D.S., & Clutter, A.C. Inbreeding in Cattle. http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-1974/ANSI-3165web.pdfAccessed January 16, 2019.

Turner, J. W., Farthing, B. R., & Robertson, G. L. (1968). Heterosis in reproductive performance of beef cows. Journal of Animal Science 27(2): 336-338.

van der Westhuizen, B. (2016) Inbreeding vs Linebreeding. http://www.ngunicattle.info/Publications/Journals/2016/Inbreeding%20vs%20line-breeding.pdfAccessed January 20, 2019.

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Bull Selection Breeding Programs That Suit Operational Goals

Editor’s note: The following is part one of a four-part series that will help you to evaluate different breeding programs, which bulls are optimal for your herd, and how much they’re worth.

There are a range of different beef operations in Canada, and there is no one breeding program that is optimal for all operations. Breeding programs will be determined by operational goals and the management practices that fit those goals.

Here are some examples.

A producer that sells weaned calves at auction may choose a crossbreed program with high calving ease and a focus on performance gained from hybrid vigour; or they may prefer the uniformity of a purebred program with reputation premiums.

A producer that retains heifers and is looking for maternal replacements may be focused on maximizing the performance through inbreeding and outcrossing within a single breed; or they may develop FI crosses with higher reproductive performance and longevity.

These choices may be limited by the number of breeding fields available or the number a producer is willing to manage. There are a variety of breeding programs available, and effective sire selection requires an understanding of the characteristics of the available genetics as well as your own operation.

Each breed of cattle has distinct traits that allow them to excel in different geographical or management environments (Table 1). Depending on the goals of the operation, a sire can be chosen that has the potential to make positive changes for your operation in the areas you’ve identified for improvement.

Table 1. Comparison between beef cattle breeds in Canada (Adapted from Agriculture Victoria, 2017)

Indicators:
• E: Early, A: Average, L: Late
• S: Small, M: Medium, L: Large
• 1 = high/desirable; 5 = low/undesirable

Source: http://agriculture.vic.gov.au/agriculture/livestock/beef/breeds/breeds-of-beef-cattle

Also see Beef Improvement Federation’s across breed EPDs

Purebred

The advantage of the purebred or straight-bred approach of using only one breed is a homogeneous herd where cattle responses to environmental and nutritional factors are easier to predict. There will be consistency in nutritional needs, weaning, yearling, or finishing weights, and days on feed. The largest advantage is the ability to market a relatively uniform product, but ease of planning, and providing breeding stock forcommercial operations intending to maximize hybrid vigour may also be considerations.

When the parents have very similar genetics, the calf is more likely to have two sets of identical genes (homozygosity), which can have beneficial effects if the genes are associated with superior performance. However, negative traits can also show up with homozygosity. This can lead to the expression of abnormal traits, such as lethal recessives (e.g. curly calf syndrome, dwarfism, neuropathic hydrocephalus, etc.) It can also have more subtle effects on overall performance by increasing the amount “inbreeding depression” in the population.

Inbreeding depression is a reduction in performance due to the mating of highly related individuals, and it most negatively affects reproductive traits, followed by growth traits, but seems to have little effect on carcass traits. It is associated with an increased percent of open cows and stillbirths, with decreased levels of survival, growth, and overall performance (Northcutt et al). Generally, caution must be exercised when inbreeding as there is a high risk of performance reduction if the breeding program is not managed very carefully.

Three common purposes of inbreeding are to:

  • to test a bull for the presence of undesirable genetics that show up with inbreeding
  • develop inbred lines for a crossbreeding system
  • linebreed, or to maintain the genetic contribution of a genetically superior individual in the larger population

Linebreeding seeks to preserve and continually improve upon the genetics of a high performing ancestor. While linebreeding mates closely related individuals, it seeks to minimize the level of homozygosity (and thus inbreeding depression) while maintaining a high level of relationship to the high performing ancestor. Linebreeding is typically merited when there is difficulty finding outside bulls with sufficient performance to improve the herd.

Key components of a successful linebreeding program include:

  • individuals selected for a linebreeding program must be of superior quality with no genetic defects
  • meticulous record keeping of breeding history, parentage records, and animal performance
  • aggressive culling at signs of defects or lower performance – the starting herd should be as large as possible to accommodate aggressive culling
  • keeping inbreeding levels low

To keep inbreeding levels low, the recommendation is to keep the genetic contribution of the same ancestor to 50% or less (van der Westhuizen, 2016). To illustrate, the progeny of mating a daughter to her sire will have 75% of genetics from the sire. Generally, matings that involve full siblings and parents to offspring are discouraged. Instead, matings of uncle/niece, half siblings, and first cousins are potential strategies.

Outcrossing, or the breeding to non-relatives or distant relatives (i.e., at least 4 generations away) within a breed, is the most widely used mating strategy in purebred herds. Outcrossing can be used to increase performance levels, avoid inbreeding depression, and restore performance lost to inbreeding depression (Evans and McPeake). The more genetically dissimilar the animals, the larger the potential benefit. One drawback of this system is that, if the outcrossed progeny were to be mated, it is more difficult to predict the phenotype of the calves due to the variation in genetic background.

Crossbreeding

With crossbreeding, cattle from different breeds are mated. As the genetics from both parents can be very different, both the positive and negative effects seen in outcrossing are magnified with crossbreeding. Crossbred herds are much more unpredictable in terms of calf weight, maturity time, and nutritional demands. However, there are two key advantages:

  • Heterosis or Hybrid vigor – this is the opposite of the performance reducing effects of inbreeding depression. Heterosis provides improvements, especially in the area of reproduction and growth. The effect of hybrid vigor is dependent on the animal having two different copies of a gene, where the more unrelated the breeds, the larger the potential improvements.
  • Breed complementarity – where the strengths of two different breeds are combined. For example, when mating Charolais bulls to Hereford-Angus crossbred cows, the Charolais bull contributes growth and performance genetics, while the Hereford-Angus cows have desirable maternal and carcass quality attributes. This may not be seen in every individual animal, but is observed in herd averages.

Studies (Gaines et al., 1966; Turner et al., 1968) have found that compared to purebred, crossbred cows have a 10% increase in calf crop and calves weaned, with the calving percentage of the crossbred cows being consistently higher than their parents. Gregory et al. (1978) found crossbred cattle to be 7 kg heavier and 9 days younger at puberty than their purebred counterparts.

Crossbreeding improves reproductive performance, longevity, and maternal ability of the cow. This is manifested through increased calf survival rate, as well as increased weaning weight. Overall, the performance improvements from crossbreeding can have significant impacts on the bottom line of beef producers.

There are many crossbreeding strategies, for example:

  • 2 or 3 breed rotation,
  • terminal cross,
  • bull rotation, or
  • composite breeds.

A terminal cross is where both parents are purebreds of different breeds, and the resulting calves are a 50:50 mix. However, to maintain this specific breed ratio, replacement breeding stock from purebred herds must be used instead of rebreeding the offspring.

Another strategy is mixed breeds, where multiple breeds are used without maintaining specific ratios of each breed in the progeny. While this strategy does not require complex breeding management, there is lower uniformity and a higher level of uncertainty regarding calf performance.

The optimal strategy will depend on the operation itself; for example, if calves are sold at a pre-sort sale or are part of a large group and able to fill an entire feedlot pen, uniformity becomes less important.

For further reading on crossbreeding, NBCEC (2010) introduces an overview of different strategies and Gosey (1991) presents a more in-depth discussion.

There are also challenges and considerations associated with a crossbreeding system (NBCEC, 2010):

  • a small herd (i.e., less than 50 cows) can limit choice in crossbreeding strategies
  • a higher requirement for breeding pastures and bull breeds for the more complex crossbreeding strategies (e.g., rotational systems)
  • more record keeping and cow identification as the current breed composition of cows can affect sire and heifer replacement selection
  • less uniformity in progeny
  • no crossbreeding system can overcome low quality bulls

There is no one-size-fits-all solution or breeding program that is best for all scenarios, as the right genetics depend on the individual operation. Key determining factors include: the management style of the operation, heifer retention (i.e., terminal versus maternal sires), number of breeding fields, and time of marketing. For example, a farm that auctions their calves at weaning may choose a mixed breed program with high calving ease, while a farm that direct markets their beef may prefer the uniformity of a purebred program.

There are many different types of bulls available, and effective sire selection requires an understanding of the characteristics of the available genetics as well as your own operation. Deliberate alignment of the bull’s genetics to your operational goals will contribute to enhanced revenue and reduced costs.

Editor’s note: Stay tuned for part two in this four-part series.