ANSC 4402 EXAM QUESTIONS AND ANSWERS A+
GRADED
Name the three muscles that control testis temperature.
1. Tunica Dartos muscle
2. Cremaster Muscle
3. Pampiniform Plexis
When do testicles usually descend?
10-14 days before or after birth
What are the three parts of the epididymis and their role?
Head- maturation
Body- maturation
Tail- storage
What should we do if we want our horse really tall?
Castrate early because testosterone closes growth plates
What should we do if you want a stout horse?
You have to wait longer to castrate to get a short stout horse.
Define a Colt
young intact male, 3 years old or younger
Define a Stallion
Intact male
Define a Gelding
male after castration
What is cryptorchidism?
When one or both testicles fail to descend into the scrotum
Why should we never breed a cryptorchid male?
It is hereditary
What part of the male reproductive system produces seminal plasma?
Accessory Sex Gland
Define the Ampulla
it is the widened end of ductus deferens- not technically a gland, but contributes fluid.
What STD can harbor in the ampulla?
Equine Viral Arteritis virus
What is the function of the glans penis?
The end of the penis that enlarges (bells) when breeding
What is the fossa of the glands?
It is depressions around the urethral process which can harbor dirt in these pits and
causes something called beans.
What is the function of the body of the penis?
Fills up with blood to create an erection
Describe the prepuce (sheath)
It is skin covering the free part of the penis and protection, but it can harbor bacteria and
pathogens
What STD can be apart of the prepuce?
, Contagious Equine Metritis (CEM)
What is different about CEM?
This can survive in cooled or even frozen semen and stallions won't show signs of it but
mares can get it from the semen and mares will abort.
What age is the final testes size? What is considered normal motility in a stallion?
12 to 13 years old; 200 million per ml of semen
Name the recommended Mare Book for hand breeding (supervised breeding) for a
two year old, three year old, mature stallions.
- Two-year-olds are not recommended to breed but if you do only book 10 mares or
less.
- Three-year-olds can handle about 30 mares (over a four-month or longer breeding
season)
- Mature Stallions about 50 mares
What is special about the mare book for hand breeding Thoroughbred horses?
Thoroughbred horses can breed about 300 mares in a 4 month period and have to be
Live covered not AI
What is pasture breeding and how many mares can be bred?
Pasture breeding is when you turn stallions out with mares and they breed when they
want to and you can only do a maximum of 25 mares.
When do most stallions produce sperm and how many spermatozoa do they
produce daily?
They start to produce sperm at 24 months of age or older and an adult stallion will
produce billions of spermatozoa daily, at a rate of about 70,000 spermatozoa per
second
What is the process of sperm cells?
Each sperm cell takes about 54-57 days to develop, then 8 days in the epididymis, with
the entire process taking about 65 days.
Why would sperm cells be voided to the urine?
They would be voided if the epididymis is filled to capacity.
What is daily sperm output and what is it dependent on?
It is the number of spermatozoa produced in a 24 hour period and it is depended on
testicular size. Testicles get smaller in winter and semen production decreases.
What is the progressive motility and morphology percentages?
Progressive motility- greater than 60%
Morphology- greater than 60% normal
What are the stallion hormones and the functions?
FSH- affects the Sertoli cells
LH- affects the Leydig cells
What are Sertoli cells?
They are referred to as "nurse cells" and they take care of the developing cells during
spermatogenesis
They secrete several proteins that regulate how much FSH is released from the anterior
pituitary.
What is Sertoli Cells roll in testosterone?
GRADED
Name the three muscles that control testis temperature.
1. Tunica Dartos muscle
2. Cremaster Muscle
3. Pampiniform Plexis
When do testicles usually descend?
10-14 days before or after birth
What are the three parts of the epididymis and their role?
Head- maturation
Body- maturation
Tail- storage
What should we do if we want our horse really tall?
Castrate early because testosterone closes growth plates
What should we do if you want a stout horse?
You have to wait longer to castrate to get a short stout horse.
Define a Colt
young intact male, 3 years old or younger
Define a Stallion
Intact male
Define a Gelding
male after castration
What is cryptorchidism?
When one or both testicles fail to descend into the scrotum
Why should we never breed a cryptorchid male?
It is hereditary
What part of the male reproductive system produces seminal plasma?
Accessory Sex Gland
Define the Ampulla
it is the widened end of ductus deferens- not technically a gland, but contributes fluid.
What STD can harbor in the ampulla?
Equine Viral Arteritis virus
What is the function of the glans penis?
The end of the penis that enlarges (bells) when breeding
What is the fossa of the glands?
It is depressions around the urethral process which can harbor dirt in these pits and
causes something called beans.
What is the function of the body of the penis?
Fills up with blood to create an erection
Describe the prepuce (sheath)
It is skin covering the free part of the penis and protection, but it can harbor bacteria and
pathogens
What STD can be apart of the prepuce?
, Contagious Equine Metritis (CEM)
What is different about CEM?
This can survive in cooled or even frozen semen and stallions won't show signs of it but
mares can get it from the semen and mares will abort.
What age is the final testes size? What is considered normal motility in a stallion?
12 to 13 years old; 200 million per ml of semen
Name the recommended Mare Book for hand breeding (supervised breeding) for a
two year old, three year old, mature stallions.
- Two-year-olds are not recommended to breed but if you do only book 10 mares or
less.
- Three-year-olds can handle about 30 mares (over a four-month or longer breeding
season)
- Mature Stallions about 50 mares
What is special about the mare book for hand breeding Thoroughbred horses?
Thoroughbred horses can breed about 300 mares in a 4 month period and have to be
Live covered not AI
What is pasture breeding and how many mares can be bred?
Pasture breeding is when you turn stallions out with mares and they breed when they
want to and you can only do a maximum of 25 mares.
When do most stallions produce sperm and how many spermatozoa do they
produce daily?
They start to produce sperm at 24 months of age or older and an adult stallion will
produce billions of spermatozoa daily, at a rate of about 70,000 spermatozoa per
second
What is the process of sperm cells?
Each sperm cell takes about 54-57 days to develop, then 8 days in the epididymis, with
the entire process taking about 65 days.
Why would sperm cells be voided to the urine?
They would be voided if the epididymis is filled to capacity.
What is daily sperm output and what is it dependent on?
It is the number of spermatozoa produced in a 24 hour period and it is depended on
testicular size. Testicles get smaller in winter and semen production decreases.
What is the progressive motility and morphology percentages?
Progressive motility- greater than 60%
Morphology- greater than 60% normal
What are the stallion hormones and the functions?
FSH- affects the Sertoli cells
LH- affects the Leydig cells
What are Sertoli cells?
They are referred to as "nurse cells" and they take care of the developing cells during
spermatogenesis
They secrete several proteins that regulate how much FSH is released from the anterior
pituitary.
What is Sertoli Cells roll in testosterone?
