Animal Science and Meat Evaluation Review

Vocabulary flashcards covering sheep, goat, swine, poultry production, animal physiology, and meat grading standards.

Ovis aries

The scientific name for sheep.

Capra hircus

The scientific name for goats.

Texas (Sheep and Goat Production)

The leading state for sheep and goat production in the U.S., with $750{,}000\text{ head}$.

Haemonchus contortus (Barberpole Worm)

An internal, blood-sucking parasite that represents the biggest cause of loss and death in sheep and goats.

Bottle Jaw

A clinical sign characterized by a swollen jaw in sheep and goats, caused by blood-sucking internal parasites such as Haemonchus contortus.

Parasite Tolerance Selection

The trait selected for in sheep and goats in Texas and intermountain states against Haemonchus contortus in wet areas.

Sheep and Goat Predators

Major predators including coyotes, eagles, bobcats, and foxes, against which guard dogs, llamas, and jennies are used for protection.

Overeating Disease / Enterotoxemia

One of the three major diseases in sheep and lamb feeding, caused by Clostridium perfringens type C&D.

Urinary Calculi Prevention Ratio

A $2:1$ Calcium to Phosphorus ($\text{Ca}:\text{P}$) ratio required in the diet to prevent urinary calculi in sheep.

Lamb Feedlot Timeline

The feeding program where lambs enter at $70\text{--}90\,\text{lbs}$, feed for $100\text{ days}$ on an approximately $90\%$ whole corn diet, and exit at $120\text{--}150\,\text{lbs}$.

Key Economic Traits in Swine Production

Growth rate (days to $280\,\text{lbs}$), feed efficiency ($2.8:1\,\text{F/G}$), and muscling/fat thickness.

Lysine

The critical limiting amino acid in pig diets.

Swine Diet and Production Hub

A feeding program primarily based on corn and soybean meal, centered mainly in Iowa.

Sow Reproductive Metrics

Key reproductive intervals including a $21\text{-day}$ estrous cycle, a $3\text{-day}$ ($72\,\text{hr}$) estrus period, and a $114\text{-day}$ gestation length ($3\text{ months}$, $3\text{ weeks}$, $3\text{ days}$).

Poultry Incubation Times

The duration required for eggs to hatch: $21\text{ days}$ for chickens and $28\text{ days}$ for turkeys.

Chicken Manure Composition

An avian waste byproduct exceptionally high in Nitrogen ($\text{NH}_3$).

Thermoneutral Zone (TNZ)

The temperature range where an animal is in its comfort zone and heat loss and heat production are balanced.

Thyroid Hormone (T3/T4) Temperature Response

Endocrine adaptation where hormone secretions increase during cold stress to raise metabolic heat and decrease during heat stress.

Environmental Feed Intake Regulation

The feeding behavioral response whereby animals consume more feed in cold weather and less feed in hot weather.

Livestock Normal Rectal Temperatures

Baseline core body temperatures: Cattle at $101.5^\circ\text{F}$, Sheep/Goats at $102.0^\circ\text{F}$, Pigs at $102.0^\circ\text{F}$, and Horses at $100.0^\circ\text{F}$.

Zoonotic Disease

A disease capable of being transmitted between animals and humans, such as Rabies, Ringworm, and Brucellosis.

Copper Toxicity in Sheep

A mineral vulnerability caused by extreme sensitivity to copper, requiring an appropriate balance of Sodium and Molybdenum.

Livestock Injection Site

The neck region, selected for administering injections to prevent damage to high-value meat cuts.

Market Classes and Grades

Standardized systems created to accurately describe livestock being sold and ensure consistent product standards.

Quality Grading vs. Yield Grading

Quality grading measures palatability (tenderness, juiciness, flavor), whereas Yield grading measures leanness and cutability (percentage of boneless retail cuts).

USDA Meat Grading

A voluntary assessment program for meat quality and yield, unlike USDA meat inspection which is required by law.

Beef Yield Grade Factors

The four criteria used for calculation: adjusted fat thickness at the 12th rib, Ribeye Area (REA), percentage of kidney, pelvic, and heart fat ($\%\,\text{KPH}$), and Hot Carcass Weight (HCWT).

High-Value Beef Wholesale Cuts

Loin and Rib, which represent the most valuable wholesale cuts compared to Round and Chuck.

Break Joint vs. Spool Joint

Anatomical joint indicators used to classify ovine carcasses: a Break Joint indicates Lamb, while an ossified Spool Joint indicates Mutton.

Wholesale Cuts of Lamb

Leg, Loin, Rack, and Shoulder.

Wholesale Cuts of Pork

Ham, Loin, Boston Butt, and Shoulder.

Post-Mortem Meat pH

An ideal meat pH value of $5.6$, resulting from the post-mortem conversion of muscle glycogen into lactic acid.

Myoglobin

The muscle protein responsible for storing oxygen and determining the color of meat.

Myoglobin States

The three color forms of muscle pigment: Deoxymyoglobin (Purple), Oxymyoglobin (Bright Red / bloom), and Metmyoglobin (Brown).

Natural vs. Organic Meat Labels

Natural indicates meat that is minimally processed with no artificial ingredients, whereas Organic requires certification of no antibiotics/hormones and compliance with strict feed and farm standards.

Pork Yield Grade Equation

$$\text{YG} = (4 \times \text{Last Rib Backfat}) - (1.0 \times \text{Muscle Score})$$

Lamb Yield Grade Equation

$$\text{YG} = 0.4 + (10 \times \text{Fat Thickness in inches})$$

Beef Yield Grade Base Specifications

The standard baseline values used in calculations: Base PYG fat of $0.0\,\text{in}$ ($2.0\,\text{PYG}$), Base HCWT of $600\,\text{lbs}$, Base REA of $11.0\,\text{sq in}$, and Base KPH of $3.5\%$ fat.