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CHAPTER 15. HEIFER A.I. 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.
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CHAPTER15 HEIFER A.I.
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
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.
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.
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
Less Difficult Average More Difficult 1 9 15 NAAB Calving Ease Information • NAAB published data lists 3 items/bull: • Number of observations: • # of Calvings Included in Each Bull’s Evaluation • Estimated Percent Reliability: • Degree of Confidence in the “Expected Difficult First Births” Prediction • Expected Percent Difficult First Births: • % of a Bull’s Calves That Would Arrive With Extreme Difficulty or Require Considerable Force to be Born
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.
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 • Trichomoniasis • Leptospirosis • Brucellosis
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.
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.
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!
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
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
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
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
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.
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
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 $$$
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
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
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
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
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
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
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
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
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
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
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
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
Question 1 • For a dairy operation, what are the major benefits that can be expected from a heifer A.I. program? • For a beef operation? Less calving difficulty, increased production and conformation, better records, faster genetic progress for the herd, reduced risk of disease, no hidden bull expense Faster improvement of calving ease, growth rate, carcass, and mothering ability, reduced risk of disease, no hidden bull expense
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.
Question 3 • What are two factors that affect calving ease? Size of the heifer and the size of the calf carried.
Question 4 • If you were a Guernsey breeder, what is the minimum weight your heifers should be before they’re breed? 675 pounds
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.
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? • Why is there such a big difference? 10% Because Charolais is a much larger animal