ANSC 107 Exam 1 —Q&A
ANSC 107 Exam 1
Texas A&M University
Questions and Answers| Pass Guaranteed| Updated
Question 1
Define "ad libitum" (ad lib) feeding.
Answer: Feed is available to the animal at all times, allowing it to eat as much as it
wants, whenever it wants.
Rationale: Ad libitum is Latin for "at one's pleasure," referring to free-choice access to
feed rather than restricted or scheduled feeding.
Question 2
What is compensatory growth?
Answer: An accelerated rate of growth that occurs after a period of restricted growth
(e.g., due to limited nutrition), once normal or improved nutrition is restored.
Rationale: When feed restriction slows growth, animals often "catch up" rapidly once
adequate nutrition resumes; this rebound is called compensatory growth.
Question 3
What is a calorie, as used in animal nutrition?
Answer: A unit of measurement for energy; specifically, the amount of heat required to
raise the temperature of 1 gram of water by 1°C.
Rationale: Calories quantify the energy content of feed and the energy requirements of
animals, forming the basis for energy-based nutrition calculations.
Question 4
What does TDN stand for, and what does it measure?
Answer: Total Digestible Nutrients; it estimates the total energy value of a feed,
calculated from digestible crude protein, digestible fiber, digestible nitrogen-free extract,
and digestible fat (fat weighted x 2.25).
Rationale: TDN is one of the most common measures used to estimate the energy value
of a feedstuff based on its digestible nutrient components.
Page 1
, ANSC 107 Exam 1 —Q&A
Question 5
What is a "contemporary group" in animal breeding/production records?
Answer: A group of animals of the same breed, sex, and age that were raised under the
same management conditions (same herd/flock, same time period).
Rationale: Grouping animals this way removes environmental differences (nutrition,
management, weather) so genetic differences in performance can be compared fairly.
Question 6
What is "culling" in livestock production?
Answer: The practice of removing inferior, unproductive, or otherwise undesirable
animals from a breeding herd or flock.
Rationale: Culling improves the overall genetic quality and productivity of a herd by
eliminating animals that do not meet performance, health, or reproductive standards.
Question 7
What is meant by "maintenance requirement" in nutrition?
Answer: The amount of nutrients/energy needed to keep an animal in a stable, non-
productive state—neither gaining nor losing body weight, with no growth, gestation, or
lactation occurring.
Rationale: Maintenance requirement is the nutritional baseline before any additional
energy is allocated toward growth, reproduction, or milk production.
Question 8
What is feed efficiency (feed conversion ratio)?
Answer: A measure of how effectively an animal converts feed into body weight gain,
typically expressed as pounds of feed consumed per pound of gain.
Rationale: A lower feed conversion ratio indicates a more efficient animal, since less feed
is required to produce each unit of gain.
Question 9
What is heterosis (hybrid vigor)?
Answer: The improved or increased performance of a hybrid (crossbred) offspring for a
given trait compared to the average of its purebred parents.
Rationale: Crossbred offspring often outperform the average of their parent breeds in
traits like growth rate, fertility, and survivability due to heterosis.
Page 2
, ANSC 107 Exam 1 —Q&A
Question 10
What does EPD stand for and what does it indicate?
Answer: Expected Progeny Difference; it predicts how future offspring of an animal are
expected to perform, on average, relative to offspring of other animals, for a specific
trait.
Rationale: EPDs are calculated from pedigree, individual performance, and progeny data,
and are widely used to select breeding stock for desired traits.
Question 11
What is a purebred animal?
Answer: An animal whose ancestry can be traced entirely to a single breed and that
meets that breed association's standards for registration.
Rationale: Purebred status is based on documented lineage within one recognized breed,
as opposed to crossbred animals with mixed ancestry.
Question 12
What is a crossbred animal?
Answer: An animal produced by mating two parents of different breeds.
Rationale: Crossbreeding combines genetics from two or more breeds, often to capture
heterosis and complementary traits from each breed.
Question 13
What is gestation?
Answer: The period of time during which a developing offspring is carried within the
mother's uterus, from conception until birth.
Rationale: Gestation length varies by species (approximately 283 days in cattle, 114 days
in swine, 147 days in sheep, and 340 days in horses).
Question 14
What is lactation?
Answer: The production and secretion of milk by the mammary glands, typically to
nourish offspring.
Rationale: Lactation begins after parturition and continues until the female is dried off
or her offspring are weaned.
Page 3
ANSC 107 Exam 1
Texas A&M University
Questions and Answers| Pass Guaranteed| Updated
Question 1
Define "ad libitum" (ad lib) feeding.
Answer: Feed is available to the animal at all times, allowing it to eat as much as it
wants, whenever it wants.
Rationale: Ad libitum is Latin for "at one's pleasure," referring to free-choice access to
feed rather than restricted or scheduled feeding.
Question 2
What is compensatory growth?
Answer: An accelerated rate of growth that occurs after a period of restricted growth
(e.g., due to limited nutrition), once normal or improved nutrition is restored.
Rationale: When feed restriction slows growth, animals often "catch up" rapidly once
adequate nutrition resumes; this rebound is called compensatory growth.
Question 3
What is a calorie, as used in animal nutrition?
Answer: A unit of measurement for energy; specifically, the amount of heat required to
raise the temperature of 1 gram of water by 1°C.
Rationale: Calories quantify the energy content of feed and the energy requirements of
animals, forming the basis for energy-based nutrition calculations.
Question 4
What does TDN stand for, and what does it measure?
Answer: Total Digestible Nutrients; it estimates the total energy value of a feed,
calculated from digestible crude protein, digestible fiber, digestible nitrogen-free extract,
and digestible fat (fat weighted x 2.25).
Rationale: TDN is one of the most common measures used to estimate the energy value
of a feedstuff based on its digestible nutrient components.
Page 1
, ANSC 107 Exam 1 —Q&A
Question 5
What is a "contemporary group" in animal breeding/production records?
Answer: A group of animals of the same breed, sex, and age that were raised under the
same management conditions (same herd/flock, same time period).
Rationale: Grouping animals this way removes environmental differences (nutrition,
management, weather) so genetic differences in performance can be compared fairly.
Question 6
What is "culling" in livestock production?
Answer: The practice of removing inferior, unproductive, or otherwise undesirable
animals from a breeding herd or flock.
Rationale: Culling improves the overall genetic quality and productivity of a herd by
eliminating animals that do not meet performance, health, or reproductive standards.
Question 7
What is meant by "maintenance requirement" in nutrition?
Answer: The amount of nutrients/energy needed to keep an animal in a stable, non-
productive state—neither gaining nor losing body weight, with no growth, gestation, or
lactation occurring.
Rationale: Maintenance requirement is the nutritional baseline before any additional
energy is allocated toward growth, reproduction, or milk production.
Question 8
What is feed efficiency (feed conversion ratio)?
Answer: A measure of how effectively an animal converts feed into body weight gain,
typically expressed as pounds of feed consumed per pound of gain.
Rationale: A lower feed conversion ratio indicates a more efficient animal, since less feed
is required to produce each unit of gain.
Question 9
What is heterosis (hybrid vigor)?
Answer: The improved or increased performance of a hybrid (crossbred) offspring for a
given trait compared to the average of its purebred parents.
Rationale: Crossbred offspring often outperform the average of their parent breeds in
traits like growth rate, fertility, and survivability due to heterosis.
Page 2
, ANSC 107 Exam 1 —Q&A
Question 10
What does EPD stand for and what does it indicate?
Answer: Expected Progeny Difference; it predicts how future offspring of an animal are
expected to perform, on average, relative to offspring of other animals, for a specific
trait.
Rationale: EPDs are calculated from pedigree, individual performance, and progeny data,
and are widely used to select breeding stock for desired traits.
Question 11
What is a purebred animal?
Answer: An animal whose ancestry can be traced entirely to a single breed and that
meets that breed association's standards for registration.
Rationale: Purebred status is based on documented lineage within one recognized breed,
as opposed to crossbred animals with mixed ancestry.
Question 12
What is a crossbred animal?
Answer: An animal produced by mating two parents of different breeds.
Rationale: Crossbreeding combines genetics from two or more breeds, often to capture
heterosis and complementary traits from each breed.
Question 13
What is gestation?
Answer: The period of time during which a developing offspring is carried within the
mother's uterus, from conception until birth.
Rationale: Gestation length varies by species (approximately 283 days in cattle, 114 days
in swine, 147 days in sheep, and 340 days in horses).
Question 14
What is lactation?
Answer: The production and secretion of milk by the mammary glands, typically to
nourish offspring.
Rationale: Lactation begins after parturition and continues until the female is dried off
or her offspring are weaned.
Page 3
