Equine Lecture 5 (and Dr Balliet's repro talk)

Foal

newborn horse

filly

newborn female horse (up to 3 yrs of age)

colt

newborn male horse (up to 3yrs of age)

yearling

1 year old (more than 12 mths, less than 24 mths)

Mare

mature female horse

Stallion

adult intact male

gelding

adult castrated male

When is a female sexually mature?

15-18 months

When is a male sexually mature?

2 years

When is a good age to breed?

At least 3-4 years

How often is the estrus cycle?

22-23 days

How long does the estrus cycle last?

4-6 days

When does ovulation occur?

1-2 days before end of heat

When does foal heat occur?

7-11 days after foaling

What is foaling?

act of parturition in horses

When is the second heat after foaling?

25-30 days

How long is gestation?

about 343 days

What is the litter size?

1

Weaning age?

4-6 months

When is castration done?

done between 1 -2 years of age, done in spring or late fall to avoid flies

Signs of heat

urinating more frequent, small urinations, tail held high, winking vulva, restlessness, stomping

What are some types of breeding?

Natural, in-stall, AI

what is natural breeding?

A stallion picks a mare to breed with naturally in the pasture

Disadvantages of natural breeding?

Unsure of if he bred the mare or when he bred her, high risk of injury

What is in stall breeding?

In a stall where you can observe what is happening. You are able to clean the genitalia to prevent problems.

What are hobbles used for during breeding?

They prevent the mare from kicking the stallion

Benefits of AI

You can breed multiple mares with one collection

You can choose the baby's genetics (semen sample)

Safer for the animals

What is the average volume of semen?

30-50cc

What should the temperature be of the artificial vagina?

42-25 degrees C (anything over 40 is okay)

What is an equitainer used for?

It cools the semen sample

How long can a sample be good for in the equitainer?

48-72 hrs

When observing semen under a microscope, what should you look for?

Progressive motility, no sperm swimming in circles, normal head and tail, no double head or tail

What lube and syringe should you use?

Non-spermicidal, rubber in syringes are spermicidal as well

When can a heartbeat be detected?

about 4 weeks

What can be used to bring a female into heat?

Prostaglandins

How early can pregnancy be diagnosed?

15 days

What vaccines and medicine should you give a pregnant mare?

Dewormer

Vaccinate against rhino pneumonitis (EHV) months 3,5,7,9

Core vaccines 10 months

When do you increase energy above maintenance?

last 1/3 of gestation

Leading up to delivery you will see?

2-6 weeks before foaling the udder will enlarge, produce milk

7 days before the vulva will appear fuller and looser

4 days before the teats swell

1-3 days before she will start waxing

What is waxing?

An appearance of colostrum in the teats, it will appear think and yellow

How long does stage 1 of foaling last?

hours to a few days

What happens during stage 1?

restlessness, cervix is dilating

How long is stage 2?

5-15 minutes

What is stage 2?

complete dilation of the cervix, expulsion of the fetus

Proper presentation of the baby?

the anterior presentation in the dorsosacral position (front feet first with head between legs, feet facing down towards mom's feet)

What is stage 3?

Expulsion of the placenta

When does stage 3 occur?

usually 90 minutes after baby is born

What is a retained placenta?

If the placenta is still not delivered after 6 hours

What is the harm of a retained placenta?

It can cause sepsis and laminitis to the mom

How much does a horse's placenta weigh?

12-14 pounds

Will the umbilical cord tear naturally?

Usually yes

How long should you wait before cutting the cord if needed?

5-15 minutes

Why do you need to wait to cut the umbilical cord?

30% of the foal's blood supply is in the cord

What should you dip the cord in?

Iodine, multiple times a day

What can cause abortion?

Equine Herpes Virus (EHV), leptospirosis, Equine Infectious Anemia (EIA), fescue toxicity

What is fescue?

It is a type of grass that can cause pregnant mares cervix to dilate early

What is hydrops (hydroallentosis)

development of too much amniotic fluid. Stomach gest so large the abdominal muscles and tendons start to break down

What is dystocia?

Difficult delivery

What are some examples of dystocia?

Baby is too large, baby is in poor position, foal did not develop properly

What is a dummy foal?

The foal suffered neurological problems through the delivery process

What can cause a dummy foal?

Birthing too quickly, not reaching every step in the cascade

How will a dummy foal act?

They will be confused, not know how to stand, won't know how to nurse

What is the Madigan Foal Squeeze?

rope tied around rib cage of foal to replicate the birth canal stages the foal missed. The foal will calm down or sleep

What is red bag?

premature separation of the placenta

What should you do after the foal is born?

•Clear airways - wipe nostrils with towel, and syringe nostrils with a large bulb syringe if necessary

•Dry and rub the foal

•Wait 5 to 15 min before cutting cord, 30% of foal's blood is in cord

•Dip the umbilical stump in antiseptic - tincture of iodine

•Allow the foal and mare to bond

•Check the milestones

When should the baby start breathing?

right away!

What should the heart rate be of the foal?

75-100 bpm

What should the respiratory rate be of the foal?

60-80 bpm the first 1-2 hours, then 30-40 for the first month

When should the foal be up and standing?

within the first hour

When should the foal start nursing?

60-180 minutes after birth

When is the first urination of the foal?

within 10 hours of birth

When should the meconium be passed?

within 24 hours of birth

Normal temperature range for a foal?

99-101 Farenheit

What is a sheath cleaning?

It is to get smegma and beans out from the pocket geldings tuck their penis into

How often should a sheath cleaning be preformed?

About every 6 months

If a sheath cleaning is not preformed, what can be impacted?

Infection or interference with urination

What drug helps drop the penis to clean the sheath?

Acepromazine

Where should you clean for mares?

Between the teats

Reasons for sedation

farrier, floating, wound care, treatment, surgery, joint injections, sheath cleaning

What are some drugs classified as alpha 2 adrenoreceptor agonists?

Dormosedan, Xylazine (Rom pom and Anased)

What two forms does dormosedan come in?

Injectable and oral

What is the caution to take when using oral dormosedan?

Use gloves, it can be deadly to humans!

Can you combine dormosedan with other drugs?

yes

How long does dormosedan last on average?

45 minutes

What can you reverse the effects of dormosedan with?

Tolazoline

How long does Xylazine last?

15-30 minutes

What can you reverse Xylazine with?

Tolazoline

Can you combine Xylazine with other drugs?

Yes

What is acepromazine used for?

Sheath cleaning and to plant the hind end

Will acepromazine work if the animal is already nervous or excited?

No

What is valium used for?

It relieves anxiety, lasts 1-2 hours, often for surgery

What is ketamine used for?

general anesthesia

What is Butorphanol - Torbogesic used for?

Analgesia (pain meds), often mixed with Dorm or Xylazine

What is phenylbutazone and flunixin meglumine used for?

They are NSAIDS, anti-inflammatory pain killers used more regularly. Bute more commonly used for lameness and flunixin meglumine used more for soft tissue or GI

Which drug is commonly given with colic?

Flunixin meglumine (helps prevent the release of the enterotoxins)

Ways to euthanize the horse?

IV injectable, overdose inhalant gas, captive bolt, gunshot

Why is a necropsy preformed?

Some horses are insured for a lot of money so the insurance companies want to know the cause of death before they will cover anything