Animal Science Exam 2 Review Flashcards

Vocabulary practice flashcards covering red meat products, by-products, slaughter grading, market classes, wool grading, and reproductive physiology basics for Animal Science Exam 2.

Wholesale Cut

A largely portioned primal meat section prepared for ease in handling and shipping, such as beef chuck, rib, loin, or pork ham.

3 examples of wholesale cut

Chuck, rib, loin

3 example of retail cut

Pot roast, ribeye, steak

What animal produces red meat (5)

Cattle, pig, sheep, goat, horse

What animal has white meat

Poultry

Retail Cut

Consumer-sized meat portions packaged for direct store sale, cut from wholesale primals (such as ribeye steak, pot roast, or bacon).

Order of muscle structure (out to in)

Muscle bundle (fasicle)

Muscle fiber (myofibers)

Myofibril

Sarcomere

What is this

Muscle bundle (fasicle)

What is this

Muscle fiber (myofibers)

Muscle Bundle (Fascicle)

A group of individual muscle fibers encased by the connective tissue layer known as the perimysium.

Muscle Fiber (Myofiber)

A multinucleated muscle cell made up of rod-like organelles known as myofibrils.

Myofibril

Rod like organelle

Sarcomere

Crontractile unit

Dressing Percentage

$\text{Dressing Percentage} = \left(\frac{\text{Carcass Weight}}{\text{Live Weight}}\right) \times 100$ .

Why is dressing percentage important

Lets you know how much meat is left after removing inedible parts

Hot Carcass Weight (HCW)

The weight of a dressed animal carcass on the rail after the hide and viscera have been removed, measured prior to entering the freezer.

Dressing percentages of these animals

Hogs: 70-74

Cattle: 60-64

Sheep or lamb: 50-54

Solve

62%

Slaughter process (5)

packing plant alive, stunned unconscious (via co2, electric), exsanguination (cut throat or artery), remove hide, remove head and organs

Slaughter process part 2 (5)

Carcass split in half, carcass washed and chilled, aging, chilled carcass cut into wholesale, box up

Exsanguination

The step in the slaughter process where the jugular and/or carotid artery is severed to drain blood from the animal.

Offal

The non-carcass items removed during slaughter, including viscera, head, and other organ by-products.

Fabrication

The post-chilling breakdown process where carcasses are split from primal cuts into retail cuts for packaging and sale.

By-Product

Non meat product from animal

Example: hide, tallow, bones, organ meat

Variety Meats

Edible organ by-products harvested during slaughter, including liver, heart, tongue, tripe, and sweetbread.

Rendering

recycling offal, fat, bone, meat scraps, and carcasses into tallow, protein meals, and other products.

How many pounds of rendering is picked up daily

70 mil

Edible by-product example (3)

Variety meat (longue, heart, liver)

Lard (Pig)

Tallow (cattle and sheep

Inedible byproducts (4)

Tallow and other fat (soap, candle)

Blood and bone meal (fertilizer)

Indedible organs (pet food, chew)

Hide, skin, pelt

Carcass disposal (4)

Render company

Composting

Burn

Bury

Why use grading for livestock (3)

Common reporting language

Group livestock

Makes marketing easier for buyer and seller

Slaughter grading in cattle (2)

US quality grade

US yield grade

Quality Grade (Beef)

Difference in eating quality

Different quality grades (3)

Prime, choice, select

Most recieved quality grade

Choice

Yield grade (1-5) significance

1- lean , muscle

5- very fat

Yield grade (1-5) significance

1- lean , muscle

5- very fat

Most recieved yield grade

3

Cutability

The overall proportion of lean, usable retail meat yielded by a carcass.

What at is this best and worst for quality grade

Prime, canner

Best and worst yield grade

1. 5

Most expensive grade combination

Prime, yield grade 1

Live evaluation of livestocck (7)

Brisket (full)

Ribs (smooth)

Loin (smooth(

Tailhead (flat)

Flank (deep and loose)

Rump

Codd udder (fat)

Ribbing

The process of cutting through the muscle and backbone of a chilled carcass between the $12\text{th}$ and $13\text{th}$ rib in beef (or $10\text{th}$ rib in pork) to expose the ribeye for grading.

Bloom Time

The required $15\,\text{minute}$ air exposure period after ribbing that permits oxygenation of the ribeye muscle prior to carcass grading.

Preliminary Yield Grade (PYG)

The starting point for carcass yield grade calculation, determined solely by fat thickness measured at the $12\text{th}$ rib

What is the start pyg and fat thickness

2.0

0.0

How much do you add To pyg per 0.1 increase in fat

0.25

Lower yg Is more desirable

True, more bonesless closely trimed meat

What is the algebraic formula for YG

Yg = 2.5+(2.5 x Body fat) + (0.0038 x HCW) + (0.2 x KPH) - (0.32 x REA)

What are the measurements needed and area measurement for PYG

Fat thickness At 12th riB

Area for measurement at 3/4th up the length of the ribeye from split chinbone

Agricultural Marketing Act of 1946

Origninally mandated the standards for feeder-calf grades

What do feeder calf grades offer

A tool for beef cattle marketing

What do the national standards predict

Carcass value and maturity fatness endpoint

What are the predictive variables for beef cattle performance and marketing grades (2)

Frame score

Muscle thickness score

Frame Score

(Large, Medium, Small) evaluating length and height to project finished market weight at $0.5\,\text{in}$ at the 12th rib of backfat thickness.

Muscle Thickness Score

($\text{US No. } 1\text{--}4$) evaluating the muscle-to-bone ratio at a given degree of fatness.

1 - thick

4 - thin

SWINE GRADING USDA carcass grades what is the number range

1-4

1 - highest yield

4 - lowest yield

Muscle score (swine) number range

1-3

1 - thin

3 - thick

What is pork quality based on (4)

Color (1-6) (pink - red)

Firmness

Excudation

Marbling (1-10) (none- lots of marbling)

RFN

Ideal pork quality

R - redish pink

F - firm

N - non-exudative (holds water in well)

PSE

Undesirable

P - pale pink grey

S - soft

E -exudative

DFD

Undesirable

D - dark purple red

F - vary firm

D - dry

Feeder lamb grades (2)

Frame score

Muscling score

Frame score of feeder lamb

Small medium large

Muscling of feeder lamb

1-3

Break Joint

An unossified growth plate joint on the front shanks of young lamb carcasses ($2\text{--}14\,\text{months}$) that easily breaks apart during slaughter.

Spool Joint

A smooth, solid joint present on the front legs of mature sheep (mutton) where the growth plate has completely ossified into solid bone.

American Blood System

A wool grading method based on the theoretical percentage of Merino bloodline in the sheep, where full blood represents the finest fleece.

Spinning Count System

A wool grading system based on the number of $560\,\text{yd}$ hanks of yarn that can be spun from $1\,\text{lb}$ of clean wool.

Micron Diameter System

An objective wool grading technique using specialized instruments to measure individual fiber diameter in microns.

Reproduction Definiton

Specialization in fertility preservation, diagnosing and treating fertility and other reproductive problems

Reproduction purpose

Perpetuation of species

Providing food, fiber and milk

Genetic improvement

Gamete

A mature haploid male (sperm) or female (ovum) germ cell.

Zygote

A fertilized ovum; a diploid cell resulting from the fusion of two haploid gametes.

Cryptorchid

A developmental defect characterized by the failure of one (unilateral) or both (bilateral) testicles to descend into the scrotum.

Standing Estrus

The specific period of female sexual receptivity during the estrous cycle, commonly referred to as standing heat.

Estrous Cycle

The total time interval measured from one ovulation event to the next.

Polyestrus

A pattern of reproductive cyclicity where female animals experience continuous estrous cycles throughout the year (e.g., cows, sows).

Seasonal Polyestrus

A cyclicity type where females display multiple estrous cycles only during specific times of the year dictated by photoperiod (e.g., ewes, mares).

Monoestrus

One cycle per yr

Anestrus

No cycle

Cotyledonary Placentation

A type of placental attachment characterized by button-like specialized sites (caruncles and cotyledons) found in cattle, sheep, goats, and bison.

Diffuse Placentation

A type of placental attachment featuring uniform, widespread contact across the chorionic membrane found in horses and swine.

Corpus Luteum (CL)

An ovarian endocrine structure that develops from the corpus hemorrhagicum after ovulation and secretes progesterone to maintain pregnancy.

Corpus Albicans (CA)

The pale scar tissue remaining on the ovary after the corpus luteum degenerates.

Epididymis

A duct structure located alongside the testicle responsible for the concentration, storage, maturation, and transport of spermatozoa.

Tunica Dartos

A smooth muscle layer located within the scrotal wall responsible for testicular temperature regulation.

Gonadotropin-Releasing Hormone (GnRH)

A hypothalamic hormone that acts on the anterior pituitary to direct the release of FSH and LH.

Luteinizing Hormone (LH)

An anterior pituitary hormone that acts on the gonads to stimulate steroid hormone production and induces ovulation of mature follicles.

Follicle Stimulating Hormone (FSH)

An anterior pituitary hormone that stimulates ovarian follicular growth (folliculogenesis) and testicular sperm production (spermatogenesis).

Progesterone ($P_4$)

A steroid hormone secreted by the corpus luteum that maintains pregnancy and exerts negative feedback on GnRH to suppress ovulation.

Prostaglandin F2$\alpha$ ($\text{PGF}_{2\alpha}$)

A hormone synthesized by the non-pregnant uterus that induces luteolysis (regression of the corpus luteum) to lower progesterone levels.

Hypothalamus-Pituitary-Gonad Axis

The interconnected neuroendocrine feedback pathway where hypothalamic GnRH regulates pituitary gonadotropins (LH, FSH), controlling gonadal sex steroid production.

Proestrus

The stage of the follicular phase (Days 19–21 in cows) before standing heat marked by luteolysis, declining progesterone, rising estrogen, and follicular growth.

Metestrus

The initial stage of the luteal phase (Days 1–4 in cows) following ovulation during which the ruptured follicle forms the corpus luteum.

Diestrus

The longest stage of the luteal phase (Days 5–18 in cows) dominated by high progesterone levels from a fully functional corpus luteum.