Reproductive Patterns and Hormonal Changes

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is indicated by normal vaginal discharge of blood-tinged mucus in cows and heifers shortly after the onset of estrus?

It is a sign of conception.

It signals an infection.

It indicates a failure to conceive.

It is a normal response associated with high estrogen levels. (correct)

Which behavior indicates that a doe is in estrus?

Frequent laying down.

Seeking out the buck or demonstrating excitement. (correct)

Loud vocalizations indicating distress.

Excessive eating and grazing.

During which season do mares undergo regular estrus cycles?

Winter.

Fall.

Spring to summer. (correct)

Year-round without interruption.

What physiological change occurs in the mare's endometrium on days 13-14 post-ovulation?

Secretion of PGf2 to cause luteolysis. Signup and view all the answers

How does increased light duration affect long-day breeders during the spring?

It enhances the firing of retinal nerves and inhibits the pineal gland. Signup and view all the answers

What is the average length of the follicular wave in she camels?

24 days Signup and view all the answers

During which seasons does sexual activity in she camels tend to be higher?

Winter and spring Signup and view all the answers

How many days does the estrus or mature follicular stage last in the follicular wave?

5 days Signup and view all the answers

What is the typical gestation length for a one-humped camel?

12 months Signup and view all the answers

What behavior is commonly observed in she camels during heat?

Restlessness and tail waggling Signup and view all the answers

What is the reproductive life span of a she camel?

20 years Signup and view all the answers

What is a characteristic external sign of heat in she camels?

Swelling of the vulva Signup and view all the answers

Where does the greatest percentage of ovulation occur in she camels?

Right ovary Signup and view all the answers

What is the typical duration of heat or estrus in a cow?

12-18 hours Signup and view all the answers

Which of the following is a sign of estrus in cows?

Red and swollen vulva Signup and view all the answers

What typically happens during the metestrus phase in terms of duration?

3-5 days Signup and view all the answers

At what age does puberty, marked by the first estrus cycle, usually occur in cows?

12 months Signup and view all the answers

The postpartum heat in cows occurs after how many days following calving?

40-60 days Signup and view all the answers

What type of estrous cycle do buffalo cows have?

Polyestrous and might be seasonal Signup and view all the answers

During what time frame does ovulation typically occur after the end of heat in cows?

12-18 hours Signup and view all the answers

Which behavior is typically associated with cows in estrus?

Increased bellowing Signup and view all the answers

What role does season play in the age of puberty for horses?

Seasons can delay the onset of puberty. Signup and view all the answers

Which of the following is NOT a sign of estrus in mares?

Aggressive behavior towards stallions Signup and view all the answers

What changes occur in the cervix during the estrous cycle when a mare is in heat?

The cervix moves downward from the upper portion of the vaginal cavity. Signup and view all the answers

What is the typical conception rate during foal heat?

It is usually quite high. Signup and view all the answers

How does the vagina appear during the estrous cycle when a mare is in heat?

Pink and moist Signup and view all the answers

What is a characteristic behavior of a bitch in proestrus?

Aggressive to males Signup and view all the answers

During which phase is the vulva of the bitch swollen and does it exhibit bloody discharge?

Proestrus Signup and view all the answers

What describes the ovaries of a mare during anestrus?

Small and firm Signup and view all the answers

Which sign indicates that a mare is receptive to a stallion?

Raising of the tail Signup and view all the answers

What should not be done regarding old mares during foal heat?

They should not be bred. Signup and view all the answers

Study Notes

Reproductive Patterns in Different Animals

Reproductive Patterns: Different animals exhibit varying reproductive patterns, influenced by factors like species, environmental cues (e.g., photoperiod), and physiological state.

Hormonal Changes During the Estrous Cycle

Hormones: Hormones like estrogen, progesterone, FSH, and LH play key roles in regulating the estrous cycle. These hormones fluctuate throughout the cycle.
Cycle Stages: The estrous cycle involves distinct stages (e.g., proestrus, estrus, metestrus, diestrus), each with specific hormonal characteristics.
Feedback Mechanisms: Hormone release is regulated by feedback mechanisms (positive and negative), influencing follicle development and ovulation.

Ovarian Cycles

Ovarian Cycle Stages: Ovarian cycles involve stages like follicular development, ovulation, and corpus luteum formation, each corresponding to changes in hormone levels.
Different Animals: Specific details (e.g., length of estrous cycle, duration of different stages) vary across different animal species.

Photoperiod and Reproduction

Photoperiod's effect: Light duration (photoperiod) significantly affects reproduction in short-day and long-day breeders.
Effect mechanisms: Light influences hormone release through the pineal gland and signaling pathways

Reproductive Parameters

Puberty: Age at puberty varies greatly among animal species.
Gestation Length: Gestation length (time from conception to birth) differs based on the species.
Reproductive Life Span: The number of calves or offspring produced differs according to the species.
Breeding season: Breeding season is the period in which animal are most likely to be receptive to mating and in which reproduction is likely to take place

Animal Behavior and External Signs

Behavioral cues: Animals exhibit distinct behavioral changes (e.g., restlessness, mounting) during estrus or heat.
External Signs (visible changes): External signs like vulva swelling and discharge, urination patterns, and tail positioning are utilized to detect estrus.
Specific animal examples: Specific behavioural cues and external signs for the species are included in this document.

Post-Estrus/Metestrus Hemorrhage

Occurrence: Occurs in a portion of cycling cows and heifers, generally 48 hours after the initial estrus.
Cause: High estrogen levels leading to slight vascular rupture.
Significance: Not a sign of pregnancy failure, or inability to conceive.

Reproduction in Specific Animals

Cow: polyestrus species with a specific estrous cycle, and breeding behaviour.
Buffalo: polyestrus breed, differing in some aspects of the cycle from the cow
Ewe: seasonal polyestrous with specific breeding patterns.
Doe: polyestrous with specific breeding patterns.
Sheep: polyestrus with specific breeding patterns influenced by day length.
Mare: Seasonal polyestrus with specific breeding behaviour.
Bitch: Monoestrus in which breeding is not influenced by day length, and is a one time event in a year.
Queen: Seasonal polyestrous with specific reproductive attributes.
Camel: Polyestrus, differing in some attributes of the estrous cycle from other animals.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the fascinating reproductive patterns found in different animals, focusing on key hormonal changes during the estrous cycle. Understand the role of hormones such as estrogen and progesterone, and learn about the stages of both the estrous and ovarian cycles. This quiz offers insights into the complexity of animal reproduction.