Sexual Cycle and heat detection

Question 1

oogenesis and what hormones are involved

Answer 1

it is the process of creating ova. it starts before puberty, where the oogonium undergo mitosis until its doubled and this phase is called the primary oocyte.
after puberty the primary oocyte continues to undergo mitosis and is released until it encounters sperm during ovulation. After fertilisation meiosis continues producing a fertilised egg.
Hormones invlovled: FSH +LH =>trigger the ovarian cycle

Question 2

spermatogenesis and what hormones are involved

Answer 2

germ cells develop into spermotocytes which then turn into spermatozoa. it starts with the spermatogonium dividing into two producing primary spermatocytes that then develop into 4 haploid spermatids-sperms.

Hormones involved: GNRH+ FSH+LH+INHIBIN+TESTOSTERONE

Question 3

Puberty

Answer 3

occurs when animals weight is from 40-60% of adult weight

Question 4

female cycle can be categorised as

Answer 4

follicular phase,ovulation and luteal phase

Question 5

Ovulation can last up to

Answer 5

35-36 hours in women,

11-12 h in rabbits

Question 6

some animals can have a sexual period thats continuous or seasonal

Answer 6

for continuos:
cow,rabbit,pigs
for seasonal:
horses(spring),sheeps(autumn),goats(autumn)

Question 7

spontaneous ovulation

Answer 7

GNRH AND Lh secretions are induced by the oestrogen mature follicle (positive feedback)

Question 8

induced ovulation

Answer 8

GnRH secretion is induced by coitus, sexual inter course triggers gnrh

Question 9

Main stages of the Oestral cycle

Answer 9

oestrus-meteotrus-dioestrus-prooestrus

Oemediopro

Question 10

Ovarian cycle

Answer 10

Follicular, ovulation and luteal cycle

Question 11

(heat) Oestral cycle

Answer 11

oestrus-meteotrus-dioestrus-prooestrus

can be catergorised as the follicular phase and luteal phase
only occurs in animals

Question 12

Ovulation is triggered by

Answer 12

the surge in LH after follicular phase

Question 13

During luteal phase

Answer 13

progesterone,estradiol promote thickening of the endometrium, corpus luteum is at its peak development.

Question 14

Uterine menstrual cycle

Answer 14

can be divivded into mentstrual flow phase,,roliferative phase and secretory phase

Question 15

Folliculogenesis is defined as

Answer 15

when corpus luteum decreases

Question 16

Puberty in sheep is between

Answer 16

6-7 months

Question 17

Puberty of cow starts around

Answer 17

9-11 months

Question 18

Mare’s puberty begins

Answer 18

18 months

Question 19

Sows undergo puberty around

Answer 19

6-7 months

Question 20

OOcytes number at birth differ by species

Answer 20

cows=30
woman=400-500
sheep=60
sow=205-600

Question 21

Sertoli cells provide ….during cell differentiation in ….

Answer 21

1. nutirents

2. spermatogenesis

Question 22

Sexual Cycle can be summarised as the

Answer 22

ovarian cycle and oestral cycle

Question 23

Sexual phases can be summarised as the

Answer 23

Follicular and luteal phase

Question 24

when is it best to inseminate animals (artificially or naturaly)

Answer 24

During the first day of heat

Question 25

Melatonin stimulates what hormone secretion by the hypothalamus?

Answer 25

GnRH

Question 26

what happens when you miss a heat detection for cows?

Answer 26

delayed fertilisation by 3 weeks. a delayed fertilisation means delayed birth dates between two calfs

Question 27

There are types of heats signs at each stage of the heat cycle (early signs, late signs, and signs during mating )

Answer 27

early signs: nervousness and increased activity.
signs during mating: clear mucus at vulva, ingestion decreased, milk production decreased.
Late signs: trying to mate with other cows, tangles tail hair with mucous, blood in mucous after heat

Question 28

Discrete signs of heat in cows include

Answer 28

mooing, licking the vulva, sniffing

Question 29

in what animal is the no relation between oestrus and ovulation?

Answer 29

mare

Question 30

cows are more prone to show signs of oestrus during which times of the day?

Answer 30

Morning and night

Question 31

Heat detection tools:

Answer 31

1. Automated heat detection

2. colour coding

Question 32

Factors that can affect heat detection include

Answer 32

• reproduction technique
• Health
• Livestock Building
• start of lactation