• large, strong, swift and coordinated
• lack of horns or antlers
• controllable through the diastema
• adaptable to all kinds of forage
• non-territorial

• red & white blood cells
• platelets for clotting
• plasma which is about 90% water

• support and rigidity for the body
• levers for muscles
• protection for internal organs
• mineral storage

• maintain body shape
• regulate body temperature
• regulate water intake and outflow
• protection from outside bacteria
• protection against wear and tear
• protection from ultraviolet light
• site for formation of Vitamin D
• reception of environmental sensations

• nose
• ears
• eyes
• skin
• tongue

A) myofibrils

B) myofilaments

A) Modeling

B) Remodeling

• hierarchy
• bluffing
• bonding
• learning
• grooming
• playing

• recognize that the human is the leader
• submissive to humans
• sense of safety around humans

Tendons:movement

Ligaments: structural support

A) Flexor

B) Extensor

A) cold

B) heat

• glucose
• fructose

• carbohydrates
• lipids
• proteins
• vitamins
• minerals

• exertion
• humidity
• temperature of the environment
• fever
• distress
• anxiety

• epidermis
• dermis
• subdermis

A) Carpal

B) Tarsal

• warm air
• filter air
• smell

A) alveoli

B) an Olympic swimming pool

• species have a different number of chromosomes 
• two different breeds are still members of the same species

• stride frequency
• stride length
• lack of bulk in their legs which means less effort to pick them up
• they do not arch their backs which prevents excess energy use

An organism whose size and nature is between that of a bacteria and a virus, and which is carried almost exclusively by ticks and chiggers. Best known equine disease caused by this type of microbe is Potomac Horse Fever.

These are single-celled microscopic animals, larger than bacteria, with a flagellum (tail) for movement. Some are found among microbes of a healthy gut

compound within mare’s milk during the first day or so after birth that contains large protein molecules in the form of antibodies against common diseases. 

• tetanus
• influenza
• rhinopneumonitis
• sleeping sickness
• viral arteritis
• strangles
• anthrax
• rabies

Once the A spores enter the animal's bloodstream, usually through a puncture wound by a nail or wire, they will revert to the state of normal bacteria and produce a toxin affecting the nervous system. 

This is caused by a virus that is spread by water droplets in the air

One strain, EVH-1, causes stillborn foals or abortions during the last trimester, often as long as four months after the respiratory symptoms.  The other strain, EVH-4, is most commonly found as the cause of upper repiratory infections in young horses. The main symptoms of both strains are fever, clear nasal discharge, and a shallow cough.

Early symptoms are high fever for several days in a row, plus nervousness. As lesions begin to form on the brain, the horse appears drowsy, holding its head and ears low, and may walk around aimlessly. Paralysis and death usually follow this stage in no more than four days. 

disease of the upper respiratory tract that closely resembles equine influenza and.or rhinopneumonitis. Common symptoms are high fever, nasal discharge, swelling of lower legs, conjuctivitis, and sometimes a rash. While mortality is low, abortion occurs in about half of all the pregnant mares that contract this disease. 

identified by swollen lymph glands in the jaw and throat. A difficulty in swallowing will usually accompany fever, nasal discharge, and coughs. Treatment is usually antibiotics, such as pennicillin, but there is an effective vaccination available.

acute infectious disease caused by a bacterium, and transmitted either by ingestion or biting insects

viral disease of the nervous system transmitted to the horse solely from the bite of an infected animal.

fairly rare viral disease, affecting less than one percent of the horse population.

This is a disease caused by a protozoal parasite called Sarcocystis neurona.   The common symptoms are asymmetrical ataxia, lack of coordination, fatigue, weakness, paralysis, head tilt, or narcolepsy (brief periods of deep sleep).

This is a reckettsial disease discovered in Maryland, Virginia and West Virginia in 1979. The symptoms were severe digestive tract problems.

This is a bacterial disease that causes infertility or early abortion.

Transmission of the disease is mainly through a mosquito-bird cycle with horses being terminal hosts, meaning they do NOT infect either other mammals (including humans) or mosquitoes. 

• two testes
• the epididymis
• the vas deferens
• penis

A) testes

B) scrotum

C) warm

D) spematogenesis

These are paired, egg-shaped reproductive organs which, only at sexual maturity (14-18 months), begin producing testosterone and sperm (male gamete) 

This is a long, convoluted tube attached to the testes where sperm, which are immature as they leave the testes, must mature if they are to be viable for ejaculation.

This is a muscular tube that propels sperm from the epididymis to the urethra, which is the tube that forms the core transporting mechanism within the penis.

This is the male sexual organ comprised primarily of cavernous tissue (which fills with blood upon excitation), but which includes the urethra. 

• two ovaries
• fallopian tubes
• uterus
• cervix 
• vagina

These are paired, bean-shaped reproductive organs containing – from birth – hundreds of thousands of immature eggs.  

These tubes, also called oviducts, transport the ova (eggs) from the ovaries to the uterus. 

This is the muscular horned sac in which a normal, fertilized egg is intended to develop from microscopic embryo to foal over a period of 11 months (330 days).

This is the closed neck of the uterus, which separates and protects it from the vagina

A) Fallopian Tubes

B) Uterus

Any type of physical problem that prevents the delivery of the foal through the efforts of the mare alone (unaided by humans). 

A branch of biology dealing with the heredity and variation of organisms, and with the mechanisms by which these are transmitted and expressed.