Genetics

Gene

length of DNA that codes for a specific protein​

found on a chromosome​

influences the characteristics of an organism​

Chromosomes​

DNA​

Protein​

Genetic Information ​

Use

Breeding Strategies

Higher LWG/FCR breeds – increase profit​

Higher Milk Yield/Quality breeds - increase profit​

Better Disease Resistance breeds – less cost​

Higher fertility breeds – higher production – Increase profit​

Better Health Traits – Feet/Teeth - Increase Profit​

Crop Production

Larger grain size/numbers - increase profit​

Disease resistance – less spray costs​

Better Germination Rate – Higher Production​

Short Growing Period – Better Quality Harvesting​

Traits Sought

Cows

Milk Yield​

Milk Composition​

Conformation ​

Fertility

Beef/Sheep

Carcass Weight​

Growth Rate​

Prolificacy​

Conformation​

Crops

Disease Resistance​

Yield​

Straw Length​

Frost Resistance​

Types

Dominant genes are genes that are always expressed when present.​

Recessive genes : only expressed in the absence of a dominant genes​

Lethal gene: a gene when expressed in the phenotype will cause death of the organism​

Deleterious Gene: A genetic alteration that increases an individual's susceptibility or predisposition to a certain disease or disorder.​

Type

Genotype = is the genes present in an organism whether expressed or not​

Phenotype = is the physical appearance of the organism ​

Selective Breeding: Human breed plants and animals with desirable traits and concentrate those traits in the offspring​

Line Breeding: Production of desired traits through inbreeding over generations​

Genetic Improvement​

Increases the productivity of the animal over its lifetime​

Increases the profitability of the animal over its lifetime​

Herd Health Improvements

Positives

BB  Double Muscle  Lean Meat, Higher Yield, Low Fat​

  • Holstein  Higher Milk Yield, Median Suspensory Ligament​

Negatives

BB  Bad Feet Hard calving  Susceptible to Pneumonia​

Holstein High forage volume required  Poorer Fertility  Bad Feet within Breed  Pendulous Udder​

Crossbreeding

Hybrid vigour (heterosis) is the increased productivity displayed by offspring from genetically different parents.​

Performance and Progeny

Performance-testing evaluates the bull’s performance by comparing its weight gain and FCR with other bulls kept under similar conditions.​

Progeny-testing evaluates the performance of the bull’s offspring compared to other bull’s offspring kept under similar conditions.​

Economic Breeding Index (EBI)​

Single figure profit index - identify the most profitable bulls for breeding dairy replacements.​

Milk production - Yield, %Protein, Low SCC​

Fertility – How easy they go in calf, How many calves, Calving Interval​

Calving performance – How easy/hard do they calve their calf​

Beef Carcass - % killout of their calves at slaughter​

Cow Maintenance - How robust the cow is, Feed Intake​

Cow Management – Milking Time, Temperament, ​

Health – Mastitis, Lameness, Disease​

Environment – Methane Emissions, FCR​

Euro Star Rating System​

The Terminal Index - profit per direct progeny slaughtered​

Carcass Weight​

Calving Difficulty​

Food Intake​

The Replacement Index - profit per calving of each daughter​

Milk Volume​

Calving Interval​

Carcass Weight​

Calving Difficulty​

Dominance

Incomplete dominance : ​
when two alleles are equally dominant or Recessive. phenotype is a blend of the two.​

Co-dominant: ​
Both alleles of a gene are equally dominant and both are expressed equally​

Genomics (Gene Economics)​

study of animals’ DNA or Genotype​ “breeding using DNA”.​

Identifies

which DNA chunks have been passed from the parents to it’s offspring.​

animals traits (milk production, carcass weight etc.),​

comparison to the genomic samples of proven animals ​

Genotyping

Technique used to identify differences in (genotype) an animal’s DNA sequence and comparing it sequence of other animals.​

Advantages

Tailored Breeding​

Higher reliability EBI/Eurostar figures: increases reliability % figures​

Parentage verification: Sire & Dam confirmed (stolen cattle)​

Breed verification: identify an animal’s breed makeup.​

Genetic diseases: diseases/major genes (e.g. Myostatin)/lethal genes​

Traceability: full traceability

Mutations

AMR Antimicrobial Resistance

Cause

overuse and misuse of antibiotics.​

Incomplete course of antibiotics​

Inaccurate dosage​

Prevention

Implement vaccine programme​

Administer antibiotics appropriately​

Maintain good Hygiene levels on farms​

Provide adequate ventilation​

Maintain Biosecurity​

Genetic modification (GM) : DNA has been changed for the purpose of improvement or to correct a defect in the organism.​

Genetic Engineering: Artificially copying a piece of DNA from one organism and joining it to the DNA of another organism​

Improved Production Traits ​

Milk Yield – Increased profit from less cows​

Carcass Quality – Increased meat quality from poor breeds ​

Crop Yield – Increased profit from smaller acres – Less Rent]​

Increased Disease/Pest Resistance​

Less Chemicals sprayed to control pests/disease - Environmentally Friendly​

Increased biodiversity – BEES​

Less Chemical Exposure – Water/Food Quality​

Improved Feed Conversion Efficiency Rate (FCE)​

Less Concentrate Costs​

Less Fodder/Silage - Save Costs​

Genome: organism's complete set of DNA​

Gene editing: add, delete or replace a base in the genome, thereby changing the sequence of the genetic code.​

Mr P Reynolds