livestock and poultry evaluation animal science ii

Livestock and Poultry Evaluation

Animal Science II

Performance Data Beef Cattle Reproductive performance

– Conception rate– Calf crop percentage (born)– Calf crop percentage (weaned)– Calving interval

• length of time between calving for each cow in the herd that is breeding age

Performance Data Beef Cattle Reproductive performance

– Birth weight related to calving difficulty

– Fertility testing of bulls• should be tested before each breeding

season

Performance Data Beef Cattle

Calving difficulty score

1- No difficulty. No assistance2- Minor difficulty. Some assistance3- Major difficulty. Mechanical assistance4- Cesarean birth or other surgery5- Abnormal presentation

Performance Data Beef Cattle Bull Performance

– Information varies from breeder to breeder

– 15-20 different types of data• Average daily gain• Scrotum circumference

Performance Data Beef Cattle Growth and Gain Performance

– Weaning weights adjusted to 205 days

– Yearling (365 days) and long yearlings (452 or 550)

– Post weaning rate of gain (minimum of 140 days on test)

– Weight per day of age

Performance Data Beef Cattle Weaning Weights adjusted to 205

– standard basis

Actual weight - Birth weight

Age in daysX 205 days + Birth weight

Performance Data Swine

Sow Productivity– Fertility (number of pigs per litter)– Litter weight at weaning

• best overall measure of sow productivity because it is affected by the number of pigs weaned and milk production

Performance Data Swine Growth Rate

– Adjusted days to 230 pounds– Rate of gain=pounds of gain on test/ days

on test– Feed efficiency= amount of feed/ amount

of gain– Carcass merit

• Backfat thickness (less is better)• Loin-eye area• Percentage of lean cuts

Performance Records Poultry

Past performance– Pedigree

• Gives records of ancestors

Present performance on individuals and siblings

Rate of gain and feed efficiency

Production Records

Heritability Estimates – Vary by trait ranging from 0 to 70– Fertility is 0 to 10 percent

• management affect more than genetics

– Loin-eye area is fastest improved by selective breeding• 70% in cattle• 50% in swine

Production Records

Sow productivity index– uses a formula that included the

number of live pigs born and adjusted 21-day litter weight for individual sow comparison

Production Records

Use of Data Records– In most cases the highest number is

better– Exceptions:

• birth weight• calving difficulty• backfat thickness in swine

Production Records

Estimated Breeding Value (EPV)– Estimate of the animal true breeding

ability– Expressed as a percentage to the

average of the animal to which the bull is compared• 105 is 5% above the average• 95 is 5% below the average

Production Records

Expected Progeny Difference (EPD)– Bulls can only transmit 1/2 of its

superiority as shown on its EPV.– If the EPV is 106 that is (106-100=6)

which is then halved to make three percent (6/2=3)

– Females transmit the other half

Production Records

Pedigree Index (PI)– The closer the animal is to the bull

being evaluated the more effect their performance traits have

Poultry Production Records

The type of record use to select by pedigree are past performance records

Present performance records are used to select physical appearance

Judging Livestock

Physical Characteristics– Confirmation

• Appearance including frame size, fat, etc.

– Structural soundness• More important today because of

confinement operations with concrete floors

– Especially swine and dairy

Judging Livestock

Commercial producers are more interested in performance records while breeders are concerned with pedigrees and breed characteristics

Judging Poultry

Most producers have no input in selection because they are contract farmers

Broilers– Must be healthy and well fleshed with

normal conformation to produce a grade A carcass dressed

Judging Laying Hens

Laying hens are evaluated on the ability to produce eggs

Things to consider– Present production– Past production– Rate of production

Judging Laying Hens

Present production– Large bright red comb– Softy waxy comb– Bright eyes

Judging Laying Hens

Past Production– Production indicated by yellow

pigment left in the body– The more eggs produced results in

less pigment– A soft pliable abdomen and moist

enlarged and bleached vent indicates that the hen is currently in production

Judging Laying Hens

Pigment bleaches beginning in:• vent• eye ring• ear lobe• beak starting at the base• front shanks• rear shanks• tops of toes• hock joint

Ready to Cook Broilers and Turkeys USDA grades A, B, & C

– determined by:• Confirmation• Exposed flesh on breast and other parts• Missing parts• Broken and dislocated joints

Ready to Cook Broilers and TurkeysFactor A B CExposed Flesh

Breast NoneElsewhere 1 ½ inch

Disjointed and broken bones

Missing Parts

1/3 flesh on

each part

No Limit

1 disjointed no broken

2 disjointed no broken

No Limit

Wing tip and tail

To the second wing

joint

What Grade is this?

Grade A

No Defects

B Grade

Back is cut out halfway between the base of the tail and the hip joints

What Grade is this?

C Grade

More than 1/3 of flesh exposed on

breast

What Grade is this?

B Grade

Parts of wing

removed beyond

the second joint

What Grade is this?

C Grade

Entire wing

removed

What Grade is this?

C Grade

Over 1/3 of the

drumstick flesh is

exposed

What Grade is this?

C Grade

Trimmed more than

halfway between base of tail and

hip joints

What Grade is this?

C grade

Protruding broken bone in wing tip

What Grade is this?

Grading Eggs

Interior quality determined by candling– AA, A, B or Reject– Bloody eggs are rejected

Exterior quality– A, B or Dirty– Any surface matter grades “dirty”

Grading Eggs

Interior quality (air cell size):AA- 1/8” (dime)A- 3/16” (nickel)B- Over 3/16” (quarter)