Female Species Differences (Final Set)

Bovine puberty

4 months - 2 years

What are factors that will lead to earlier puberty in bovine?

o Sires with larger scrotal sizes will have heifers that reach puberty earlier

o Autumn birth has puberty earlier than spring birth

Bovine — seasonal or non-seasonal?

Non-seasonal

Bovine estrous cycle length

3 weeks

Physical signs of estrus bovine

Stands for mounting & clear vaginal mucus

What does it mean if you see bloody vaginal mucus in bovine?

Sign of metestrus = missed your breeding window!!

Postpartum period bovine

Dairy = 24 days

Beef = 60 days

When should a heifer have her first calf?

By 2 years of age

What can a progesterone implant do for a bovine?

Synchronization — keeps her in a pseudo-diestrus phase

Caprine puberty

o Signs of estrus at 6-8 months = autumn of their first year

o Delay breeding until 60% adult weight maintained

Caprine — seasonal or non-seasonal?

Seasonal

Caprine estrous cycle length

20-21 days

Caprine behavior in proestrus

Buck will follow but doe will not stand to breed

Caprine behavior in estrus

Restless, beats, wags tail, slightly cloudy vaginal discharge

Do caprines have progesterone priming?

No

Caprine metestrus

-refusal to mate

-no hemorrhage

When does ovulation occur in caprine?

It is spontaneous and will happen within 12-36 hours after heat onset

Caprine synchronization

-extended luteal phase with progesterone

-shorten luteal phase with prostaglandin

Ovine puberty

• Must experience long days and then decreasing day-length

• Pubertal estrus ~ 30 weeks

Ovine — seasonal or non-seasonal?

Seasonal, breed in fall and winter months

Ovine estrous cycle length

16-17 days

Ovine signs of estrus

Shake tail, turn head to look at rm, vulvar swelling, copious thin vaginal mucous secretions

Ovine ovulation

Spontaneous!

Ovine signs of diestrus

Will squat/urinate or move away when ram approaches

What is the most powerful stimulus in ovine?

Ram introduction causes LH surge and ovulation without estrus!!!

Ovine synchronization

Can induce luteolysis with prostaglandin. Can delay estrus and ovulation with progesterone.

Camelid puberty

females bred 12 months of age and after 65% of mature weight

Are camelids seasonal?

No unless in natural habitat (wild)

What is so special about camelids?

They do not have an estrous cycle! Sexual receptivity for 36 days and induced ovulator

Porcine puberty

o Age ranges for 5-8 months

o Wild pigs = seasonal, domestic = non-seasonal

How long is porcine estrous cycle?

21 days

Estrus detection porcine

relies on the boar, vulva swelling, vocalization, pricked ears, standing for back pressure

What is important about the boar being around?

Do NOT keep the boar too long with the females because the lordosis posture cannot be maintained indefinitely

Porcine postpartum period

Estrus will occur again 3-7 days after weaning

Porcine synchronization

-sows are not responsive to PGF until late in their cycle = not practical

-regumate to prevent estrus

Exotic anatomy importance

Ovarian artery branches either directly off aorta or cranial renal artery = no OVEs

What is important about calcium in exotics?

CALCIUM is supplied to embryo — may be very high — metabolic bone disease

What happens during folliculogenesis in some reptiles?

The liver enlarges and becomes yellow = NORMAL

What happens in magnum?

White of egg being formed

What happens in isthmus?

Shell formation begins in the distal part

Where is the most common site for dystocia?

Shell gland/uterus

Clutch size psittacines

3-6

Clutch size chelonians

6-12

Clutch size most reptiles

>20

Indeterminate layers

Loss of egg stimulates second cycle

• Most psittaciformes, anseriformes, galliformes

Determinate layers

Fail to lay additional eggs in event of egg loss (BUDGIES!!!)

When is the breeding season for mares in the northern hemisphere?

April to October

Mare gestation

340days (+/- 20 days)

What do ovaries of a mare look like in anestrus? What is their behavior like?

Inactive or dormant with no dominant hormone. Behavior = ranges from receptive to indifferent based on the mare

What stimulates the transition period in spring in mares?

Increases sunlight as melatonin decreases, GnRH increases, gonadotropins increase

What will you see on ultrasound in a mare in her transition period?

Multiple developing follicles. You know she is late into her spring transition once one or more follicles reach 30mm in size

What is the interovulatory period in mares?

21 days

How many days is estrus?

5-7 days

When do mare ovulate?

Typically 1-2 days before going out of heat

How does the dominant follicle maintain its dominance?

It releases inhibin

Detection of estrus

Behavior around stallion with a GOOD libido = raising tails, passive urination, winking, mating posture. Know that maiden/wet mares may not show these signs

How can you tell on ultrasound when a mare is in estrus?

Large follicles with presence of uterine edema

How can you tell on ultrasound when a mare in in diestrus?

Presence of CL

What should progesterone levels be after ovulation?

1.0 ng/mL 1-2 days after ovulation! Progesterone is important because people will give to their mares to make them less spicy

When does LH peak occur in the mare?

AFTER ovulation (special unicorn!! = KNOW)

How much do follicles grow per day in the mare? KNOW THIS!

3-5mm everyday

What is foal heat?

First cycle after foaling = can have a foal every year. One thing to note about this is that it is not good to breed a mare that cycles befores about ten days because the endometrium is not ready for another baby yet.

Maiden mare

Never been bred

Open mare

Not pregnant

Barren mare

Has had breeding work but did not get pregnant

Foaling mare

Mare in late gestation

Wet mare

Has her foal at her side

How can we stimulate follicular growth in the mare?

Light therapy for 16 hours a day from late Nov/early Dec so that she will cycle in February