Animal Science 226 Exam 1

Why is the beef industry is described as "segmented"?

Not vertically integrated

One company doesn't own cattle throughout the whole production

Different producers throughout the process

Cow-calf

Backgrounder

Feedlot

Packer & etc

Dr. Purcell referenced the "failed price system" in your readings for the first homework. What

failed and what did it fail to do?

Failed to taken in consumer opinion

The grading system failed to meet consumer demand and therefore failed to show consumer preference

Where is the epicenter of the feedlot industry in the US? Why there?

Southwest plain states, Nebraska - Texas

Dryer climate

More available land

Close to crop production

Why is the industry seasonal?

Due to the availability of pasture ground as a feed resource when cows are lactating in order to feed calves

Why is the industry less vertically integrated than say the swine or poultry industries?

The cattle industry is less vertically integrated because not one company owns all the livestock

throughout the entire process

What characteristics of raising beef support the viability of the industry?

What are two of the elements of an effective mission statement that we described in class?

Who are we? and What do we do?

Why should a beef enterprise have a mission statement and use it?

To communicate with employees and anyone else the drive/purpose of the operation

What is the benefit of SPA programming efforts to a producer?

What are typical benchmark values for performance traits in beef cattle; traits like birth weight, weaning weight per cow exposed and so forth?

Birth weight: 85 lbs.

Weaning weight per cow exposed: 500 lbs.

Heifer replacement rate: 10%

A producer's weaned calf crop percentage is less than the state average. What are the two most likely reasons that this is the case for her?

Cows not breeding back

Dystocia

Name (and spell) the organisms against which we vaccinate in the Green Tag program.

BVD - Bovine Viral Diarrhea

IBR - Infectious Bovine Rhinotracheitis

Why is it worth it to pay more for a green tag calf that one that is not?

Preconditioned calves that has been green tagged vaccinated, in a feedlot and co-mingled, prior to

being shipped is less likely to get shipping fever

What is BRD?

Bovine Respiratory Disease - "Shipping Fever" - calves are more susceptible to sickness due to stress

from castration, vaccination and weaning and this can increase BVD

What is the Gold Tag program?

The gold tag indicates the calves have received a second set of vaccinations and have been weaned for 45 days.

What is Brucellosis and how does it relate to green tag?

Brucellosis is a highly contagious zoonosis caused by ingestion of unpasteurized milk or undercooked meat from infected animals

Vaccination NOT required for green tag - not applicable to feedlot because not maturing and breeding

What is the primary cause of dystocia?

high birth weight

From class, what is the best way to reduce dystocia in your program?

breed for low birth weight

Based on the evidence examined in class, what are the expected influences on dystocia? What are not influences?

Big calves, breach, FEED is not an influence

Increased pelvic area is not a productive emphasis to have in breeding program design, but is very much one in a management program. What is the difference? Why?

Don't breed for it, but manage culling based on it

Ability to first express puberty is a function of two main factors. What are these factors?

age and weight

Why is age at puberty important to a cattle producer?

Need to breed at 15 months

Using a growth implant on replacement heifers if often discouraged. Under what circumstances might this not be the best advice to a commercial producer?

If a producer isn't sure who he is going to keep for replacements, easiest is to implant all and decide later rather then not implant and lose benefits

How much should my heifers weigh at first breeding if I expect them to have the best chance of settling (conceiving)?

65% of mature weight at breeding

Based on the overall evidence provided in class, what are the advantages of feeding replacement heifers to gain more that what is needed to reach their optimum weight at first breeding?

No benefit

Why do producers breed heifers about 3 weeks before the start of the cow herd?

This allows for a longer recovery period before rebreeding in order to improve body condition

Also allows producers to pay closer attention to first time calvers

Why would a cattle producer pay for ultrasound pregnancy checking (name the three biggest reasons besides accuracy of a yes or no detection)? Don't mention detection of abnormalities, seeing the image, seeing a heartbeat, as these are not the reasons that most producers utilize this technology.

1. Aging - better idea of when calves are going to be born

2. Twins - better management, closer attention at calving

3. Sexing - start to plan for heifer replacement or used in show industry

What is the overall reason why pregnancy checking cows - no matter how it is done - is a good management practice?

To be able to decide whether to cull a cow or rebreed

The acronym "EPD" stands for what?

Expected Progeny Difference

How specifically is the difference between the two bulls for birth weight EPD to be interpreted?

expressed in pounds, it is a predictor of a sires ability to transmit birth weight to his progeny compared to that of other sires

How is this difference in calving ease (direct) EPDs to be interpreted?

Calving ease of that bull directly

How is this difference in calving ease (maternal) EPDs to be interpreted?

calving ease of the calf two generations out.

How is the Milk EPD difference to be interpreted?

When comparing bulls, Milk EPD is the difference in pounds that his daughter's calves will wean

Index EPDs. What are they (for example, $B, $W, $EN)? How are they interpreted?

Dollars saved or loss per head directly with a trait

From our heifer and cow selection lab, we learned that a herd needs a certain number of females to be profitable. Cows are culled and heifers are selected to replace them. What is the essential difference in approach when deciding which heifers are kept versus which cows are to be culled?

Inputs, Quality, Production

Body Condition Scoring is simple and critical management practice.

What is BCS, including the scoring system?

Body Condition Scoring - a measurement of a cows fatness level

9-point scale - 1 emaciated, 9 obese, 6 ideal

Why should producers BCS their cows?

To decide if there is a need to feed more or less, along with making sure cows have a good body condition to ensure high conception

What factors are used to determine a USDA Beef Yield Grade?

%KPH, REA, Fat Depth

Besides quality and yield grades, and the factors that we use to determine them, what is another factor that can influence price per cwt. of a calf or the carcass it produces (i.e. some other factor that might appear on a pricing grid)?

CAB, heifer or steer, age

When selling market cattle, what is meant by "the grid"?

merit based systems

What is the biggest factor that differentiates a commercial grade from a choice grade carcass?

marbling

A carcass value is predicted to be $210 per cwt. of carcass weight. What is the comparable live value (i.e. $ per cwt. for live weight)? Assume a reasonable dressing percent to make the conversion?

Carcass wt = roughly 62% of live wt

210 x .62 = $130.20/cwt live wt

Which major element in manure causes a greater challenge in finding enough land upon which to distribute the manure?

phosphorus

Compare open lots, bedded packs and deep pit housing. The nitrogen available per

unit of manure varies assuming the cattle are fed the same diet. Why?

Depending on the type of housing the concentration of the manure is higher. When feeding in a pack there is extra material. When you feed in a pit the amount is a pure manure as possible. Open lots are hard to collect because rain water mixes and dilutes the manure

Why does cattle manure have so much value?

The nitrogen in manure makes for good fertilizer

Two bulls' EPDs for MMilk are 5 and -2. Units of difference are what?

7 lbs of weaning weight of daughters calves caused by lactation differences

What's the value of $index EPDs?

Combine data into single sortable value

Seasonality in the beef industry driven by what ?

Pasture availability

Acres of land needed to distribute manure is more limited by what element?

Phosphorus

Example of a calving distribution

Any tally of # of calves born in each of several 21-day increments

When is it best to Body Condition Score cow herd?

90 to 100 days before giving birth

Breakeven $ determined by what values (name 2).

Annual cow carrying cost, ave wwt. & weaned CC%

What is benefit of feeding for higher ADG to 15 mos. of age?

None. Puberty is a function of age and weight together.

What is the relationship between ration and birth weight?

None

What is the effect of average effective temperature during last 1/3 of gestation on birth weight?

1 degree colder on average = 1 lb. heavier birth weight

Name two of the measurements to predict cutability.

Carcass weight , fat depth, Rib Eye Area, KPH% (kidney pelvis heart fat %)

What are the three approaches (the "physiological approach - not a commercial product name like CIDR or etc. ) to

synchronizing the cow herd?

1. Destroy corpus lutetium.... with PGF2

2. Inhibit ovulation.... with progestins

3. Cause ovulation of dominant follicle.... with GnRH

How do each of these effect the reproductive physiology of the cow?

Progesterone . . . Inhibits ovulation, maintains preg.

GnRH . . . . . . . . . Causes surge of LH

PGF2a . . . . . . . . Destroys CL

Why would one want to synchronize the herd?

1. Facilitates AI, ET

2. Improves labor use

3. Uniform calf crops - closer in age

4. Only 12% of US commercial herds synchronize breeding (NAHMS)

How should one prepare for the successful outcome of a synchronization program?

make sure to have enough labor if needed

make sure to have enough of the right facilities

What hormones are involved in the expression and control of the cow's reproductive cycle?

FSH. . . . . . . . . . . Matures "selected" follicles

LH . . . . . . . . . . . . preovulatory surge causes ovum release

Progesterone . . . Inhibits ovulation, maintains preg.

Estradiol . . . . . . . W/out progesterone, causes estrus and GnRH surge

GnRH . . . . . . . . . Causes surge of LH

PGF2a . . . . . . . . Destroys CL

When deciding between protocols, what factors enter into this decision?

What is best for your operation?

Amount of cattle you have.