genetics and breeding

• What is the focus of genetics and breeding traits in livestock?


  Optimizing and maximizing beneficial traits
• Which breeds are considered to have the greatest benefits?


  Breeds that are relevant and profitable
• What are the key profitable traits in livestock breeding?

  • Reproductive performance
  • Weaning weight
  • Yearling weight
  • Feed efficiency
  • Carcass merit
  • Longevity
  • Conformation
  • Freedom from genetic defects
  • Disposition
  • Environmental adaptability
• What is the definition of reproductive performance in livestock?


  It refers to the ability to produce offspring successfully
• What does weaning weight refer to?


  It is the weight of the calf at the time of weaning
• How is yearling weight defined?


  It is the weight of the animal at one year of age
• What does feed efficiency measure?


  It measures the pounds of feed required per pound of gain
• What is carcass merit?


  It refers to the quality and yield of the meat from the animal
• What is longevity in livestock breeding?


  It refers to the lifespan and productivity of the animal
• Why is conformation important in livestock?


  It affects the animal's ability to walk and overall health
• What does it mean to be free from genetic defects?


  It means the animal does not carry hereditary health issues
• What is disposition in livestock?


  It refers to the temperament and behavior of the animal
• What is environmental adaptability?


  It is the ability of the animal to thrive in different environmental conditions
• What does reproductive performance (mothering ability) refer to?


  It refers to the ability of a female to successfully raise her offspring
• What is the percent cow-calf ratio?


  It is the percentage of calves weaned from the total number of cows
• What is the target for one calf per cow per year?


  To achieve this, the calf should be weaned within 60 days or less
• How is the average daily gain (ADG) calculated?


  ADG = (actual weaning weight - birth weight) / age of calf in days
• What is the formula for 205-day adjusted weaning weight?


  205 d adjusted weaning weight = (ADG * 205) + birth weight + age of dam adjustment factor
• What does yearling weight indicate?


  It indicates the weight of the animal at one year of age
• What is post-weaning gain?


  It refers to the pounds of weight gained per day after weaning
• What factors should be considered when comparing pasture vs feedlot for livestock?

  • Threshold of growth
  • Feed efficiency
  • Pounds of feed per pound of gain
  • Compensatory gain
• What are the classifications of carcass merit?


  • Quality: Select, Choice, Prime
  • Yield grade: Bone, Lean, Volume
  • Marbling: Wagyu known for marbling, Prime known for marbling
• What is the impact of too much marbling on carcass merit?


  It can negatively affect the quality of the meat
• What are the key considerations for defects and disposition in livestock?

  • Freedom from genetic defects
  • Importance of culling
  • Disposition: Docility
• What does longevity refer to in livestock breeding?


  It refers to the lifespan and productivity of the animal
• What are the options for heifer management?


  • Feeding to slaughter
  • Breeding replacements
  • Home raised or purchased
• What are the advantages of feeding heifers to slaughter?


  It can improve quality grade
• What are the disadvantages of feeding heifers to slaughter?


  It can lead to smaller carcass size and lower profits
• When should heifers be bred?


  Heifers should be bred in the spring
• What is the timeline for heifer breeding?


  • Spring born
  • Fall weaned
  • Breed in spring/fall of next year
• What is the target breeding age for heifers?


  The target breeding age is 14-16 months
• What is the historic importance of breeding weight for heifers?


  It should be 60-65% of mature weight
• What is the target weight for breeding heifers?


  The target weight is 750 lbs
• What are the key factors in replacement selection?


  • Conceive early
  • Calve easily
  • Good milking ability
  • Heavy weaning weights
  • Desirable genetic contribution
• What does EPD stand for?


  EPD stands for estimated or expected progeny difference
• What are the key aspects of replacement development?


  • Relationship between puberty, age, and weight
  • Weight and feeding at 65% of mature weight
  • Feed to gain consistently
  • Increase ration in the last 2 months prior to breeding
• What are the considerations for replacement longevity?


  Age at breeding and nutrition during lactation
• What are the concerns regarding heifers?


  • Operation specific needs/abilities
  • Purchase and raise
  • Facilities
  • Desire to calve heifers
  • Increased risk of dystocia
  • Increased risk of not taking the calf
• What is the difference between rational and standard grazing?


  • Rational grazing: Move to new spots after grass is eaten
  • Standard grazing: Stay in one spot, leading to nutrient loss
• What is the importance of considering artificial insemination vs natural service?


  1. 6% of beef cattle producers utilize AI