Domestication & Animal Traits: Lecture 1

Lecture 1: Domestication and Animal Traits

• Domestication is the genetic modification of a living organism population
• Selective breeding is used to accentuate desirable traits that benefit humans
• Domestic animals include: pets, cats, dogs, horses, and cows

Degrees of Domestication

• Wild animals exibit a "fight or flight" response
• Tamed animals depend on humans to some extent
• Semi-domesticated animals maintain a relationship with humans
• Domesticated animals rely on humans

Common Changes in Traits Due to Domestication

• Adrenal glands are associated with Tameness
• Melanocytes affect coat color
• Chondrocytes relates to reduced skull size
• Odontocytes relate to reduced teeth
• Domestication leads to other morphological changes
• Floppy ears can develop through domestication

Belyaev's Fox Experiment

• Foxes were selected based on temperament
• The experiment began with 465 foxes
• The goal was to simulate the process that turned wolves into modern dogs
• 30% of the foxes were extremely reactive
• 40% were moderately reactive
• 20% were fearful
• 10% were quiet and exploratory
• The foxes that were bred were chosen on how close one could get to them (flight threshold distance)

Tameness and Hormones

• Tameness involves a reduction in the release of stress hormones
• There is a reduced fight-or-flight response in domesticated animals
• Domesticated animals show decreased reactivity to new situations
• The adrenal glands produce hormones
• Glucocorticoids (cortisol) are long-term hormones that regulate neonatal development
• Catecholamines (epinephrine and norepinephrine) are short-term hormones
• Domestic animals have less of short-term stress hormones compared to wild animals

Neural Crest Hypothesis

• Genetic changes to neural crest cells cause domestication traits
• Domestication involves a decrease in the size of the neural crest
• Domestication reduces the number of cells derived from the neural crest
• Tameness occurs due to reduced stress hormone synthesis
• Cells that produce stress hormones come from the neural crest
• Fewer cells being involved leads to domestication syndrome

Wolf Domestication

• Wolves with a short flight distance took advantage of food waste from humans, gaining a competitive advantage
• These wolves would breed together
• These wolves developed domestication syndrome

Domestication Pathways

• Commensal pathway: Habituation -> Partnership -> Directed Breeding
• Prey pathway: Prey -> Game management -> Herd management -> Directed breeding

Lecture 2: Animal Systems, Lifecycle & Production

Extensive vs. Intensive Animal Systems

• Extensive systems involve minimized capital inputs, mainly unprocessed diets that have low nutrients and high fiber density, minimal handling, and animals unconfined
  • Examples: Beef cattle, sheep, and goats
• Intensive systems involve significant capital inputs, processed, nutrient-dense diets, confinement production, and economies of scale
  • Examples: Pork, dairy, and poultry

Sector Types

• Cow-calf is a primary sector in extensive production, uses pasture and rangeland
• Backgrounding/stocker is managed primarily with a forage/pasture diet, resulting in slow growth
• Feedlot/finishing is an intensive production system
  • This uses primarily concentrate diets
  • Packing sectors are intensive production

Animal Lifecycle Terms

• Cow: mature female
• Heifer: young female
• Bull: sexually mature uncastrated male
• Steer: castrated male before sexual maturity
• Calf: neonatal to 5 months of age
• Gestation period in cattle is 283 days with 82 days to get pregnant post calving

Pork Terms

• Sow: mature female pig
• Gilt: immature female pig before 2nd pregnancy
• Boar: mature male pig
• Barrow: castrated male pig
• Piglet: neonatal pig before weaning
• Farrowing: giving birth to piglets

Modern Swine Production in Canada

• Pigs are typically in total confinement throughout their lives
• Commercial farms focus on biosecurity
• There are limited visitors

Swine Reproduction

• Breeding is done through artificial insemination
• Gestation lasts 3 months, 3 weeks, 3 days

Farrowing

• Sows are kept in individual crates
• Average litter size is 15 piglets
• Average birth weight is 1.2 kg
• Colostrum intake is important in the first 6 hours
• Most sows have 12 teats

Weaning

• Early weaning is abrupt
• Piglets are moved to a nursery
• Transition from milk to a solid feed
• Piglets are mixed with others
• Age of piglets at weaning is 21-28 days old

Grow-Finish Phase

• Pigs are kept in a nursery for 5 weeks
• Housed in large groups
• Diets are changed as pigs mature
• Ready for market in 15 weeks, 125 to 130 kg

Dairy Production

• The lifecycle is lactation cycle, lifespan, then calves

Parturition and Milk Fever

• Milk fever requires that cows mobilize calcium from the skeleton
• Insufficient calcium can cause muscle tremors, staggering, lying flat on their sides, heart failure, and death
• Treatment is intravenous calcium

Supply Management

• Milk production meets Canadian demand, with limited exports and imports
• A quantity of milk required is established for each province
• A quota is a license to produce up to a set amount of milk
• A national marketing agency determines production amounts and sets quotas for each province
• Producers are guaranteed minimum prices for their products
• High tariffs are implemented to make imported dairy products expensive, favoring consumption of Canadian products

Colostrum

• Calves are born without immunoglobins in their bloodstream
• Passive immunity involves the small intestine absorbing immunoglobins into the blood for the first 24 hours
• Antibodies are Y-shaped proteins that bind to bacteria and viruses

Lecture 3: Beef and Forages

North American Beef Industry

• The beef industry is divided into sectored production systems
• Cow-calf operations are foundational
• Backgrounding involves growing weaned calves on pasture
• Feedlots are for finishing cattle before processing
• Packer facilities handle processing
• There are more than 90,000 producers

Canadian Beef Industry

• The Canadian beef herd consists of 15 million cattle and calves
• Majority of operations are family run

Forages

• Forages are the foundation of the beef industry
• Pasture, hay, straw and silage are forages
• Forage is a major feed component for beef cattle
• Feed is the highest cost in beef production
• Focus is on energy, protein, minerals, vitamins and water

Canada's Traceability Program

• Traceability is based on animal identification, premise identification and animal movement
• Radio frequency identification tags are used for individual animal identification
• Cattle must have individual identification and premise identification to leave the property

Cattle Breeds

• Common breeds include Angus, Simmental, Hereford, Charolais, and Limousin
• They vary in color, carcass quality, behavior, frame size, and feed efficiency

Weaned Calf Sales

• Calves are sold in groups through auction markets
• Internet/video sales are used as sales channels
• Forward contracts with feedlots allow pre-arranged prices

Lecture 4: Poultry Terminology and Supply Management

Poultry Terminology

• Broiler: meat chicken
• Layer: table egg production chicken
• Rooster: male chicken
• Tom: male turkey
• Hen: female turkey or chicken

Chicken Consumption

• In Canada, chicken consumption is supported by supply management
• Canada produces as much chicken as it consumes

Supply Management in Canada

• Predominantly family farms in Canada
• Producers receive steady income
• Many vaccines are available, but some are restricted by politicians
• Operations with over 1000 broilers are considered commercial

Advantages of Supply Management for Poultry

• Steady income for producers
• Steady supply without surplus
• Producers can support animal welfare initiatives
• Boards influence animal welfare practices

Disadvantages of Supply Management for Poultry

• More expensive products for consumers
• Potential producers have to purchase quota

Lecture 5: Horse Domestication and Traits

Evolution Timeline and Domestication

• Equus evolved in North America
• Ancestral migration occurred to Eurasia
• Horses spread across the Eurasian steppes
• Horses were hunted for food initially
• Horses were raised in captivity and domestication was underway

Expansion of Horse Use and Domestication

• Horses were first used for carrying and hauling
• Horses were then used for war tactics
• The usage of horses expanded to riding

Coat Colors and Disadvantages

• Certain coat colors are associated with selective disadvantages
• Melanomas are linked to being grey
• Silver coats have eye disorders (MCOA)
• Leopard Spotting is associated with CSNB
• Overo Pinto is associated with OLWFS
• Splashed white and Overo are related to deafness
• White coats are embryonic lethal
• Roan coats are embryonic lethal

Detrimental Effects of Specialization

• Breeding for small size can cause dwarfism
• Heavily muscled quarter horses can develop periodic paralysis
• Breeding for speed can propagate fragility
• "Popular sire" effect leads to disequilibrium between detrimental genes and performance genes

Lecture 6: Swine Production

Origin and Latin Name

• Pigs that were likely domesticated came from China in 490 B.C. and England in 800 B.C
• The latin name for domestic swine is Sus scrofa domesticus

Canadian Swine Breeds

• Yorkshire (42% of herd)
• Landrace (32%)
• Duroc (25%)
• Other breeds include: Hampshire, Lacombe, Pietrain, Berkshire

Swine Terminology

• Swine refers to pigs
• Pork refers to pig meat
• Sow refers to a mother pig
• Gilt refers to a female of breeding age that hasn't had piglets
• Weaning refers to the removal of young from their mother
• Hog refers to a pig that's nearly ready to be processed
• Process or harvest refers to slaughter
• Boar refers to an adult male pig kept for breeding
• Farrowing refers to parturition

Pork Production in SK

• SK accounts for 8.5% of all pig production
• SK is the 5th largest producer in hogs

Changes in Swine Operations

• Advances in technology and transportation contributed
• Economies of scale contributed

Lecture 7: Dog and Cat Domestication and Pet Ownership

Dog and Cat Ownership

• Cat ownership is greater than dog ownership
• There are 8.5 million cats as pets
• There are 7.9 million dogs as pets
• Pet cat costs average $2,542
• Pet dog costs average $2,500 + $1,000
• There were 770 pet stores in Ontario in 2021
• Brick and mortar stores are declining and online purchases are increasing

Domestication of Dogs and Cats

• Dogs originated in hunter-gatherer societies and descended from an unknown wolf, originally with mutual co-existence and then to companionship
  • Domestication changed the way dogs look and behave
  • Domestication increased their ability to digest carbohydrate-rich diets
• Cats are more recent, and cats aren't as dependent or responsible to humans as dogs.
  • Domestication hasn't changed the way cats look and behave
  • Cats easily revert to feral traits
  • Diet preference and metabolism remain unchanged from wild cats

Health Benefits and Risks of Pet Ownership

• Benefits include social support, companionship, improves mental health, motivates exercise, provides animal assisted therapy, and helps teach empathy
• Risks include infections, parasites, allergies, bites and injuries, financial burden, psychological burden of pet death or neglect

Animal Assisted Therapy vs. Activities

• Animal assisted therapy is part of treatment for people who are physically, socially, emotionally or cognitively challenged
  • There are stated goals and individual treatment
  • It is scheduled with detailed notes and is administered by a trained health professional
• Animal assisted activities are casual activities involving pets and people
  • There are no specifics
  • Typically volunteer run
  • Can be as long as necessary

Lecture 8: Dairy Cattle Management and Supply

Supply Management

• Supply management involves milk production that is designed to meet the demand of Canadians
• There are limits to exports and imports of milk and milk products
• A quantity of milk required is established for each province

Dairy Cattle Management

• Dairy cattle are bred through artificial insemination
• Dairy farmers will want to produce a calf every 365 days
• Calves are housed indoors and fed milk or milk replacer
• Typically shifts to a grower phase, promoting rapid lean tissue growth
• Breed at 13-15 months of age to have first calf at 22-24 months of age ensure animals reach weight target rather than age

Key Aspects of Dairy Cattle Management

• Colostrum management and passive transfer
• Changes in milk yield of dairy cattle over time
• Importance of cow-comfort
• Characteristics of the mammary gland

Achieving Genetic Potential

• Cows cannot achieve their full genetic potential without being in a great environment, adequate nutrition, and calm handling

Mammary Gland

• "Take it or lose it" policy applies
• Frequent milking during early lactation stimulates cell development in the mammary gland
• Increased cell development can have carry-over effects
• Nutrient demand increases tremendously in lactation

Lecture 9: Indigenous Principles for Sustainable Aquaculture

Indigenous People

• First Nations, Metis, and Inuit are distinct Indigenous peoples of Canada
  • They have their own culture, history, practices and beliefs

Indigenous Principles for Sustainable Aquaculture

• Transparency and First Nations Inclusiveness
• Social responsibility
• Environmental responsibility
• Economic responsibility

Aquaculture Differences

• Aboriginal aquaculture includes cultural and spiritual aspects with unique connections to the land
• Some mistrust of conventional science
• Unique rights and special access to aquatic resources
• Job creation
• High food prices