Transcript Chapter 15

CHAPTER 15
HEIFER A.I.
A.I. Management Manual
Fifth Edition
A.I. Management Manual
Fifth Edition
Benefits of Dairy Heifer A.I.
•
•
•
•
•
•
•
•
Genetic Improvement of Herd
Replacement Heifers Have Known Genetics
Easier First Calving
Better Breeding Records
Disease Transfer Avoided
No Hidden Expenses
More Control of Young Stock Program
Added Safety
A.I. Management Manual
Fifth Edition
Genetic Improvement of Herd
•
Heifer A.I. is the Biggest Shortcut to Improving
a Herd’s Production and Longevity
–
•
Genetically Superior Females Can be Moved Into the
Milking Lineup at 23-24 Months of Age
Sires Account for Largest Share of Herd’s
Genetic Improvements.
–
After 3 Generations of Daughters, 7/8ths of a Herd’s
Genetic Makeup Comes From the Sires.
A.I. Management Manual
Fifth Edition
Genetic Improvement of Herd
A.I. Management Manual
Fifth Edition
Genetic Improvement of Herd
A.I. Management Manual
Fifth Edition
Replacement Heifers
• 1/4 to 1/3 of Calves Born Are From First Calf
Heifers
– Same Number of Replacement Heifers Will be the First
Calf From Their Dams
• Average or Above Culling Rate Means 1/4 to 1/3
Cows Will Leave the Herd During Same Time
• Purchasing Replacements is an Added Expense
– Risk of Introducing Disease Into the Herd.
EXAMPLE: 60-cow herd – potentially requires 20 replacement
heifers/year. Of these, 7 will be the 1st calf from their dams and
will be genetically inferior if they are sired by an unproven bull.
A.I. Management Manual
Fifth Edition
Easier First Calvings
• Primary Factors Affecting
Calving Ease
– Size of the Dam
• Make Sure Heifers are in
Good Condition and Large
Enough at Breeding
– Size of the Calf Being
Carried
• Sires Play an Important Role
in Determining Calf Size
• Difficult to Predict Size With
Natural Service and Unproven
Bulls
A.I. Management Manual
Fifth Edition
NAAB Calving Ease Information
•
NAAB published data lists 3 items/bull:
1. Number of observations:
–
# of Calvings Included in Each Bull’s Evaluation
2. Estimated Percent Reliability:
–
Degree of Confidence in the “Expected Difficult First
Births” Prediction
3. Expected Percent Difficult First Births:
–
% of a Bull’s Calves That Would Arrive With Extreme
Difficulty or Require Considerable Force to be Born
Less Difficult
1
Average
9
More Difficult
15
A.I. Management Manual
Fifth Edition
Better Breeding Records
• A.I. Allows More Accurate Prediction of Calving
Dates.
– A Written Record Exists
– Easier to Plan for Calving
• Breeding records Can Provide Positive Sire
Identification
– Helps Determine the Value of the Expected Calf and
Springing Heifer.
A.I. Management Manual
Fifth Edition
Disease Transfer Avoided
• Sires From Established A.I. Studs Are Free From
Infections Diseases
– Housed Under Conditions That Protect Them From
Disease.
– Reputable Studs Adhere to Standards in:
• Collecting
• Examining
• Processing Semen.
• Heifers Should be the Cleanest Animals on a Farm
– Purchasing Bulls or Heifers Could Introduce Diseases
• Vibriosis
• Leptospirosis
• Trichomoniasis
• Brucellosis
A.I. Management Manual
Fifth Edition
No Hidden Expense
• Many of the Costs Involved in Keeping a Bull
on the Farm are Hidden
– Feed
– Special Handling
– Separate Housing and Facilities.
• A.I. Has No Hidden Cost
– Typically $8 and Up
• Depends on the Sire Chosen.
A.I. Management Manual
Fifth Edition
More Control
• You Decide When Heifers are the Right Size and
Age to Breed.
• You Know Which Animals are Bred and Which
are Open.
• Sires Selected to Meet Individual Heifer
Requirements
– Use the Breed Associations Linear Data Ratings
• Sires Can be Chosen for Type and Production Characteristics
• Will Combine With the Heifer’s Genetics to Produce
Outstanding Offspring.
A.I. Management Manual
Fifth Edition
Added Safety
• Bulls Can be Dangerous and Unpredictable
– Have the Potential to Kill or Maim
– Each Year There Are Recorded Cases of This Threat
• Through the Use of A.I. This Danger Can be
Eliminated!
A.I. Management Manual
Fifth Edition
Benefits of Beef Heifer A.I.
•
•
•
•
•
•
•
•
•
Genetic Improvement of Herd
Progeny Tested Bulls
Easier Calvings
Earlier Breeding Season
Better Breeding Records and Identification
Disease Transfer and Defects Controlled
No Hidden Costs
More Uniform Calf Crop
Crossbreeding Easier
A.I. Management Manual
Fifth Edition
Genetic Improvement of Herd
• Heifer A.I.
– Fastest Way to Improving a Beef Herd Genetically
– Jump Generations by Mating Heifers with Superior
Sires
– Take Advantage of Bulls that Rapidly Improve
Economically Important Traits
• I.E. Calving Ease, Growth Rate, Carcass Quality and
Mothering Ability
• After Mating 3 Generations of Daughters to
Superior A.I. Sires, 7/8 of a Herd’s Genetics
Comes From the Sires
A.I. Management Manual
Fifth Edition
Progeny Tested Bulls
• Bulls Proven Their Ability Through Progeny
Testing
– A.I. Bulls May be Bred to 100,000 Cows or More
– Allows for More Critical Selection
A.I. Management Manual
Fifth Edition
Easier Calvings
• Two Primary Factors Affect Calving Ease
– Size of the Dam
– Size of the Calf Being Carried
• Make Sure Heifers are in Good Condition and
Well Grown at Breeding
• Ratings are Based on Information From Breed
Associations and ABS Progeny Tests
– Combine Calving Ease Scores for:
• Heifers
• Second Calf and Older Cows
• Birth Weights
A.I. Management Manual
Fifth Edition
Easier Calvings
• Advantages
– Reduced Labor at Calving
– Fewer Calf Losses
– Heifers That Can be Bred Back Sooner
• ABS System – Bulls With 3 Stars Indicate a
Performance Above Contemporary Average.
A.I. Management Manual
Fifth Edition
Earlier Breeding Season
• With Good Nutrition Heifers Should be Cycling
Regularly
• Heifers Should Cycle Earlier Than Cows
– Breed Heifers Earlier
• Gives Them a Longer Rest Period Before Rebreeding
• The Chart on the Next Slide Shows How the
Percent Cycling Heifers Increases as They
Approach a Proper Breeding Weight
A.I. Management Manual
Fifth Edition
A.I. Management Manual
Fifth Edition
Better Breeding Records & Identification
• Identification and Good Records Provide an
Individual History on Each Heifer
– Allow for Better Herd Management
• Better Calving Dates Can be Predicted
• Breeding Records Help Assign a Value for the
Expected calf $$$
A.I. Management Manual
Fifth Edition
Disease Transfer and Defects Controlled
• Reputable A.I. Studs Provide Semen Free from
Infectious Diseases
• Heifers Should be the Cleanest Animals on Your
Ranch
– Purchasing a Bull Could Introduce Reproductive
Disease
– Purchasing Herd Replacements can also Introduce
Reproductive Disease
• Natural Sires May Have a Recessive Gene
– Could Affect the Whole Herd
• Semen Quality is Known With A.I. Bulls
A.I. Management Manual
Fifth Edition
No Hidden Costs
• Direct Expenses of Natural Service Sire Include:
–
–
–
–
–
–
–
–
Purchasing or Raising a Natural Service Sire
Cost of Maintaining Sire For 10 unused months
Threat of Injury
Health Care
Feed
Housing
Handling
Testing
A.I. Management Manual
Fifth Edition
More Uniform Calf Crop
• Heifer A.I. Can Help Shorten Calving Season
– Allows for Better Use of Labor at Calving
• Increases the Uniformity of the Calf Crop
– Breed All Heifers to a Single Sire or Several Related
Sires
A.I. Management Manual
Fifth Edition
Crossbreeding Easier
• Heifer Productivity Depends On:
– Maternal Ability
– Calves’ Inherited Growing Ability
• Crossbreeding Combines Desirable Characteristics
of 2 or More Breeds
– Provides Benefits of Hybrid Vigor
• Improved Performance of Crossbred Animals Over Their
Parents.
• Improved fertility
• Heavier calves at weaning
• Improved maternal ability in replacement heifers
A.I. Management Manual
Fifth Edition
Crossbreeding Easier
• A.I. Eliminates Problems Associated With
Crossbreeding
– Need for Separate Breeding Pastures
– Need to Sort Cows by Breed
– Time Spent Looking to Buy Bulls of Different
Breeds
• For more on crossbreeding see chapter 12
A.I. Management Manual
Fifth Edition
Heat Detection Aids
• Observe Heifers at Times When Inclined to Show
Heat
• Ensuring There is Little Interference With Heat
Expression
– Establish a Regular Daily Routine for Heat Checking
– Spend at Least 30 Minutes Observing Cattle for Heat
• Early Morning and Late Evening is Best
– Observe Cattle in an Open Area
– Observe When Cattle are not Eating
– Keep the Heifers Together in a Convenient Location
for Observation
A.I. Management Manual
Fifth Edition
Heat Detection
• Cow Comes Into Heat Every 21 Days
– Stays in Heat Approximately 18 Hours
• Variations Run From 8-30 Hours
• For Highest Conception Rates:
– Breed Heifers During Latter 2/3rds of Standing Heat
• This is Roughly 24 Hours After You First Noticed Standing
Heat
• Heat Detection Aids May be Useful in Addition to
Visual Detection
• See chapter 3 for more on Heat Detection
A.I. Management Manual
Fifth Edition
Facilities
• Successful Heat Synchronization Programs
Depend on:
– Good Management Conditions
– Animals That are Reproductively Normal and Cycling
Regularly
– Well Designed and Constructed Facilities
• Minimize Stress for Animal and Worker
• For More Information Refer to:
– Chapter 3 - Heat Detection and Synchronization
– Chapter 17 - Facilities & Equipment
A.I. Management Manual
Fifth Edition
The Economics of Heifer A.I.
• Heifer A.I. is an Investment in a Herd’s Future
• Increases Dairy Production and Improves Type
– Daughters of A.I. Bred Heifers Have About 1,000
Pounds More Milk Per Lactation
• Grade A Milk Price of $13.50 CWT = $135 Per Lactation
• Produces Faster Gaining Beef Calves and
Improved Mothering Ability
– Heifer A.I. Costs Compete Favorably With Natural
Breeding Costs
• Beef Heifer A.I. Increases Profits Through Fast-Growing,
High Quality Calves, and Replacement Heifers With
Improved Maternal Ability
A.I. Management Manual
Fifth Edition
Economics of Beef Heifer A.I.
A.I. Management Manual
Fifth Edition
Summary
• Dairy Heifer A.I.
– Biggest Shortcut for Genetically Improving a Herd
– Heifers Can be Moved Into Herd at 23 to 24 Months
– Better Records Equal:
• More Accurate Calving Dates
• Easier to Determine Value of Calves and Heifers
– Sires Selected to Meet Each Heifer Requirements
• Allows for Easier First Calvings
– Disease Transfer is Limited
– Danger of Bull is Eliminated
A.I. Management Manual
Fifth Edition
Summary
• Beef Heifer A.I.
–
–
–
–
Jump Generations With Progeny Tested Sires
Calving Ease Bulls Can be Selected
Cross Breeding Programs are Easier to Establish
Heifers Can be Bred Earlier in the Season
• Provides a More Uniform Calf Crop and Earlier Calvings
–
–
–
–
Reduces Disease Transfer
Controls Recessive Genes
No Hidden Expenses in Maintaining Bull
Provides Better Records for Management Decisions
A.I. Management Manual
Fifth Edition
Summary
• Make Heat Detection Part of Daily Routine
– Observe for Heat at Least 30 Minutes Twice Daily
• Early Morning and Late Evening are Best
– Keep Heifers in Convenient Location for Heat
Detection
• Use a Synchronization Program if Heat
Detection is Not Possible
A.I. Management Manual
Fifth Edition
Question 1
• For a dairy operation, what are the major
benefits that can be expected from a heifer A.I.
program?
Less calving difficulty, increased production and
conformation, better records, faster genetic
progress for the herd, reduced risk of disease, no
hidden bull expense
• For a beef operation?
Faster improvement of calving ease, growth rate,
carcass, and mothering ability, reduced risk of
disease, no hidden bull expense
A.I. Management Manual
Fifth Edition
Question 2
• With dairy heifer A.I., animals that are
genetically superior to the present cows in a
herd can be moved into the milking lineup at
only 23 to 24 months of age.
• Explain why this is possible.
Properly grown heifers can be bred at 15 months
to a progeny tested calving ease bull allowing
them to calve at 23-24 months.
A.I. Management Manual
Fifth Edition
Question 3
• What are two factors that affect calving ease?
Size of the heifer and the size of the calf carried.
A.I. Management Manual
Fifth Edition
Question 4
• If you were a Guernsey breeder, what is the
minimum weight your heifers should be before
they’re breed?
675 pounds
A.I. Management Manual
Fifth Edition
Question 5
• You’re thinking about using a bull that has high
production and scores very well in the type traits
you’re interested in. The calving ease guide shows
that there is a 72% reliability that calvings will be
easier than average, and that 14% difficult births can
be expected. There were 128 observations in the
bull’s evaluation.
• Explain why you would or would not use this bull
on some of your dairy heifers.
I would not use the bull because he is 5% above the
average of 9 for calving ease and he only has 128
calvings reported meaning his CE could change.
A.I. Management Manual
Fifth Edition
Question 6
• Seventy percent of Angus heifers will be
cycling when they weight 600 pounds.
• What percentage of Charolais crossbreds will be
cycling at the same weight? 10%
• Why is there such a big difference?
Because Charolais is a much larger animal