AVS 1500 Unit #3: Animal Health, Reproduction, and Equine Industry

Vocabulary practice flashcards covering disease transmission, immunity, injection methods, reproductive anatomy, hormonal regulation, parturition, and equine coat colors and markings from AVS 1500 Unit #3.

Mortality

The death of an organism.

Morbidity

A state of sickness or illness in an animal.

Disease

Any deviation from normal health.

Infectious Disease

A disease that occurs when a pathogen invades the host.

Non-infectious Disease

A disease occurring from a non-pathogen source.

Vector

A living organism that transfers diseases.

Fomite

An inanimate object that carries a pathogen.

Proper Nutrition

A diet tailored to a specific animal's needs; water is an essential nutrient to all animals.

Antiseptic

A sanitation substance applied to living tissue to kill or inhibit microorganisms.

Disinfectant

A sanitation substance applied to inanimate objects and surfaces to kill pathogens.

Bioexclusion

Any practice or measure to prevent a pathogen from entering a herd by limiting possible vectors from entering.

Biocontainment

Practices and measures designed to keep pathogens from spreading within or beyond the herd.

Biologicals

Products used to prevent diseases, such as vaccines.

Pharmaceuticals

Medicinal substances used to treat diseases.

Necropsy

A post-mortem examination that occurs when a mysterious or unexpected death of an animal occurs in order to find causation.

Innate Immunity

The species, breed, and genetic resistance that an animal inherently possesses at birth.

Acquired Immunity

Immunity that develops through antibodies and T cells; occurs when an animal becomes sick, recovers, and the immune system gains a memory of how to attack that pathogen.

Passive Acquired Immunity

Immunity derived from antibodies received from another source, such as vaccines or maternal colostrum.

Active Acquired Immunity

Immunity resulting from antibodies produced by the animal itself ("immune system memory").

Subcutaneous Injection

An injection administered under the skin; very common in meat animals in order to prevent damaging muscle tissue and the eventual meat product.

Intramuscular Injection

An injection administered directly into muscle tissue; provides greater vaccine effectiveness but can cause damage to the animal's muscles.

Injection Angles

The precise angles for administering substances into tissue layers: Intramuscular ($90^\circ$), Subcutaneous ($45^\circ$), Intravenous ($25^\circ$), and Intradermal ($10^\circ - 15^\circ$).

Cattle Injection Site

The triangle on the neck located under the skin behind the head and in front of the shoulder, specifically designated for injections in cattle.

Modified Live Vaccine

A vaccine type that induces a stronger immune response but carries a higher chance of negative symptoms; very unsafe for pregnant or sick animals.

Killed Vaccine

A vaccine type that is safe to administer but produces a weaker immune response.

Withdrawal Period

A mandatory window of time following injection with certain vaccines or pharmaceuticals during which an animal cannot be harvested for product.

Sexual Maturity

The age when animals are able to reproduce optimally; breeding before this milestone can result in injury and birthing difficulties (dystocia).

Dystocia

Birthing difficulties or prolonged, difficult labor that can result from breeding animals before sexual maturity.

Hormone

A body signaling molecule produced by various endocrine glands, responsible for regulating physiological systems including reproduction, growth, and development.

False Heat

A phenomenon where an animal displays physical signs of estrus while not actually being receptive or fertile; can be caused by a failed pregnancy or hormonal imbalances.

Parturition

The act of giving birth, described as a cascading series of physiological events.

Capacitation

A process occurring when bovine sperm undergo changes within the female reproductive tract that modify membrane proteins, increasing fluidity and allowing them to penetrate and fertilize an egg.

CIDR (Controlled Inter-vaginal Drug Release)

A T-shaped insert placed into the vagina of a cow to deliver Progesterone ($P_4$), which suppresses estrus (heat) and makes the body act as if a functional corpus luteum is present to prevent cycling.

Synchronization Protocols

Hormone management regimens that coordinate estrus so that all cows are receptive and bred at roughly the same time, creating structured calving seasons and improving efficiency.

Conventional Embryo Transfer

An artificial reproductive technique where sperm is artificially inseminated (AI) into a female animal donor.

In Vitro Fertilization (IVF)

"In glass" fertilization where an oocyte is fertilized by sperm in a petri dish outside the reproductive tract.

Breeding Soundness Exam

An evaluation performed on male and female animals to determine their physical and reproductive fitness for breeding.

Ampulla

The specific region of the oviduct where the ovulated egg sits awaiting fertilization by sperm.

Corpus Luteum

A temporary endocrine structure formed from the burst ovarian follicle that produces progesterone and estrogen to maintain the thickened uterine lining for embryonic development.

Corpus Albicans

The inactive fibrous scar tissue ("white body") formed when the corpus luteum undergoes luteolysis after an unfertilized cycle.

Luteolysis

The breakdown and regression of the corpus luteum to a corpus albicans, causing estrogen and progesterone production to cease when no fertilized egg is present.

Estrous

The entire, continuous reproductive cycle consisting of cascading waves and recurring physiological phases with no distinct beginning or end.

Estrus

The recurring period of sexual receptivity ("heat") within the estrous cycle, characterized by elevated mating behavior (e.g., lordosis), vulva pulsing/swelling, discharge, and vocalization.

Gonadotropin-Releasing Hormone (GnRH)

A hypothalamic hormone that signals the release of FSH and LH from the pituitary gland; used to synchronize estrus and improve fertility in cattle.

Follicle Stimulating Hormone (FSH)

A pituitary hormone that stimulates ovarian follicles to grow, initiates follicular waves, and can be administered in excess to cause hyperovulation for embryo harvesting.

Luteinizing Hormone (LH)

A pituitary hormone released in a rapid surge $24 - 48\,\text{hours}$ before ovulation that luteinizes (ruptures) the dominant follicle, releasing the mature egg into the oviduct.

Estrogen ($E_2$)

An ovarian hormone that suppresses FSH release, halts further follicle preparation, and triggers the behavioral and physical symptoms of estrus ("heat").

Progesterone ($P_4$)

The pregnancy maintenance hormone produced by the corpus luteum; thickens the uterine wall for implantation and prevents new ovulatory cycling while levels remain high.

Prostaglandin ($\text{PGF}_{2\alpha}$)

A hormone that lyses the corpus luteum to eliminate progesterone production, triggers uterine contractions, initiates parturition, and can be used for early-term abortion.

Adrenal Cortisol

A fetal stress hormone released during Stage 1 of parturition that triggers the release of $\text{PGF}_{2\alpha}$, causes luteolysis, and initiates oxytocin release.

Oxytocin

A hormone triggered by fetal cortisol and cervical pressure that induces strong uterine contractions during delivery and stimulates milk letdown once the placenta is expelled.

Stage 1 of Parturition

The preparatory phase of labor marked by fetal cortisol release, increased $E_2$, decreased $P_4$, and rising uterine contractions stimulated by placental $\text{PGF}_{2\alpha}$ and cervical pressure.

Stage 2 of Parturition

The active phase of labor characterized by intense contractions that ends with the complete expulsion of the fetus.

Stage 3 of Parturition

The final phase of labor involving the complete expulsion of the placenta and fetal membranes.

Grey (Equine Coat)

An equine coat color characterized by black underlying skin with white hair.

Chestnut / Sorrel

Reddish equine coat colors often referred to as the "gingers of the horse world."

Bay

An equine coat color featuring a brown body with black skin and black points (mane, tail, and lower legs).

Roan

An equine coat color characterized by a base color of red (strawberry/red) or black (blue) intermixed with white hairs.

Pinto

An equine coat color pattern characterized by a white body marked with large irregular splotches of color.

Palomino

An equine coat color consisting of black skin with golden-yellow hair.

Buckskin

An equine coat color consisting of black skin, a black mane and tail, and yellow body hair.

Equine Facial Markings

Distinctive white facial patterns in horses, including the star, snip, strip/stripe, bald face, and snowcap.

Equine Leg Markings

White patterns extending up equine limbs, categorized by height as coronet, pastern, fetlock, sock, half-stocking, or stocking.

Hand (Equine Measurement)

The standard unit used to measure horse height from the ground to the withers; equal to $4\,\text{inches}$ (or $4\,\text{fingers}$).

Pony

An equine that measures $14.2\,\text{hands}$ ($14.2\,\text{hh}$) or smaller at the withers.

Colic

A common and potentially severe equine medical emergency characterized by acute abdominal pain.

Foundering

A severe equine medical condition involving inflammation and mechanical failure of the laminae within the hoof (laminitis).