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Lecture 1 Review

• Domestication changes a population of living organisms at the genetic level
• Domestication is done through selective breeding of desirable traits
• Domestic animals include pets, cats, dogs, horses, and cows

Degrees of Domestication

• Wild animals exhibit fight or flight responses
• Tamed animals show some dependence on humans
• Semi-domesticated animals have a human-animal relationship
• Domesticated animals are reliant on humans

Common Changes in Traits Due to Domestication

• Adrenal glands indicate tameness
• Melanocytes indicate coat color
• Chondrocytes indicate a reduced skull
• Odontocytes indicate reduced teeth
• Morphological changes occur
• Floppy ears develop

Belyaev's Fox Experiment

• Foxes were selected based on temperament
• The experiment began with 465 foxes
• The objective was to simulate the process that turned wolves into modern dogs
• 30% of foxes were extremely reactive
• 40% were moderately reactive
• 20% were fearful
• 10% were quiet and exploratory
• Breeding criteria included flight threshold distance

Tameness and Hormones

• Tameness involves a reduction in the release of stress hormones
• It includes a reduced fight-or-flight response
• There is decreased reactivity to new situations
• Hormones are produced by adrenal glands (top of kidney)
• Long-term hormones include glucocorticoids and cortisol which regulate the duration of neonatal development
• Short-term hormones include catecholamines, epinephrine, and norepinephrine
• These were reduced in domestic animals compared to wild animals

Neural Crest Hypothesis

• Genetic changes to neural crest cells cause domestication traits
• Domestication equals a decrease in the size of the neural crest
• There is a reduced population of cells derived from the neural crest
• Tameness occurs due to reduced stress hormone synthesis
• Cells that produce these hormones are from the neural crest
• A smaller number of cells involved indicates domestication syndrome
• Wolves with a short flight distance took advantage of food waste from humans, creating a competitive advantage
• The wolves that benefited tended to breed with each other and developed domestication syndrome

Commensal and Prey Domestication Pathways

• The commensal pathway involves habituation, partnership, and directed breeding
• The prey pathway involves prey, game management, herd management, and directed breeding

Lecture 2 Review

• Extensive animal systems are characterized by minimized capital inputs, unprocessed diets of low nutrient, high fiber density, non-confinement practices, and minimized handling techniques
• Beef cattle, sheep, and goats are examples of this
• Intensive animal systems are characterized by significant capital inputs, processed and nutrient-dense diets, confinement production, and economies of scale
• Pork, dairy, and poultry are examples of this

Sector Types

• Primary sector type includes cow-calf operations
• Extensive production utilizes pasture and rangeland
• Backgrounding/stocker involves managed with forage/pasture diets and allows for slow growth
• Intensive production uses feedlot/finishing techniques

Animal Life Cycle Terms

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

Pork Terms

• Sow is a mature female pig
• Gilt is an immature female pig before the second pregnancy
• Boar is a mature male pig
• Barrow is a castrated male pig
• Piglet is a neonatal pig before weaning
• Farrowing is giving birth to piglets

Modern Swine Production in Canada

• An intensive industry where pigs are typically raised in total confinement throughout their life
• Biosecurity on commercial farms is important
• There are limited visitors
• Breeding is done through artificial insemination
• The gestation period is 3 months, 3 weeks, and 3 days
• Sows are kept in individual crates during farrowing
• Average litter size is 15 piglets
• Average birth weight is 1.2 kg
• Colostrum intake occurs in the first 6 hours
• Most sows have 12 teats
• Weaning includes abrupt separation
• Piglets are moved to a nursery
• Transition occurs from milk to a solid feed
• Piglets are mixed with other piglets
• It happens at 21-28 days old

Grow-Finish

• Pigs are kept in the nursery for 5 weeks
• The are then housed in large groups
• Diets are changed as pigs mature
• They are ready for market in 15 weeks; 125 to 130 kg

Dairy Production

• The lifecycle is lactation cycle to life span to calves
• Parturition and milk fever requires that cows mobilize large amounts of 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 in Canada

• Supply management involves a license or quota to produce up to a set amount of milk
• National marketing agencies determine production amounts and sets production quotas for each province
• Producers are guaranteed a minimum price for their products
• High tariffs make imported dairy products expensive

Why Colostrum is Important

• Calves are born with no immunoglobulins in their bloodstream
• Small intestine of the newborn can absorb immunoglobulins into blood for the first 24 hours after birth
• This equals passive immunity
• Antibodies are Y-shaped proteins that bind to bacteria and viruses

Lecture 3 Review

• The North American beef industry is a sectored production system
• This includes cow-calf, backgrounding, feedlot, and packer operations
• There are over 90,000 producers
• The Canadian beef industry has 15 million cattle and calves
• The majority are family-run operations

Importance of Forages

• Forages are the foundation of the beef industry, including pasture, hay, straw, and silage
• Forage is a major feed component of beef cattle
• Feed is the single greatest variable cost in beef production
• Forage focuses on energy, protein, minerals, vitamins, and water

Canada's Traceability Program

• Based on animal identification using radio frequency identification tags
• Also based on premise identification -Animal Movement

Cattle Breed Varieties

• Dominant breeds include Angus, Simmental, Hereford, Charolais, and Limousin
• These vary in colour, carcass quality, behaviour, frame size, and feed efficiency

Weaned Calf Sales

• Calves are sold in groups through auction mart to feedlot buyers
• Internet/Video sales are used
• Forward contracts with feedlots deliver calves as pre-arranged price- eliminating sale barn

Lecture 4 Review

• Broiler is meat chicken
• Layer is table egg production chicken
• Rooster is a male chickenTom is a male turkey Hen is a female turkey or chicken

Chicken Consumption

• Canada utilizes a supply management system, producing as much as it consumes

Supply Management System

• Family farms are in Canada
• Not family owned in USA
• Producers receive steady income
• Many vaccines but many politicians do not allow them to be used

• 1000 broilers = commercial

Advantages of Supply Management Systems

• Producers get a steady income
• There is a steady supply without oversupply
• Producers make enough money to support animal welfare initiatives
• Boards have say in practices for animal welfare of birds

Disadvantages

• Product is more expensive for consumers
• Future producers must purchase quota