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. Genetic Improvement of Herd Genetic Improvement of Herd 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 NAAB Calving Ease Information • NAAB published data lists 3 items/bull: 1. Number of observations: – # of Calvings Included in Each Bull’s Evaluation – Degree of Confidence in the “Expected Difficult First Births” Prediction 2. Estimated Percent Reliability: 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 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 • Leptospirosis • Trichomoniasis • Brucellosis