3. repro in reptiles and fish

Question 1

outline male reproductive anatomy in reptiles

Answer 1

• testes intra-abdominal (squamates = cranial to kidneys, chelonia = dorsomedial coelomic cavity)
• right testes cranial to left testes
• no accessory sex glands in males
• lizards and snakes = hemipenes
• cheloniasns = penis

Question 2

some squamates have a sexual segment of the kidney. what is the purpose of this

Answer 2

• sperates urine/semen copulation
• large eosinophilic granules secreted int lumen
• cuboidal columnar cells
• appears in breeding season
• distal to convoluted tubules of kidney

Question 3

outline reproductive anatomy in the female reptile

Answer 3

• ovaries paired in most species
• right larger than left (left usually underdeveloped in some species)
• oviduct empties into cloaca: genital papillae
• secrete albumin, shell (similar to birds)
• includes ostium, aglandular segment, magnum, shell gland and vagina

Question 4

list the stages of reproduction in female reptiles

Answer 4

1. oocyte development (pre-vitellogeni follicle development)
2. vitellogenesis (yolk production)
3. oocyte maturation
4. ovulation
5. oviposition/partuition

Question 5

some reptiles reproduce asexually. how?

Answer 5

• no mating
• chromosomes replicate in egg
• embryo develops
• females –> courtine, pseudocopulation

this is called parthenogenesis

Question 6

how does fertilization occur in the reptile

Answer 6

• cranial oviduct
• sperm viable at body temp
• sperm stored for months - years]
• fertilisation years after contact with male
• sperm from multiple males/matings

Question 7

outline the possible viviparity of reptiles

Answer 7

• oviparous = egg laying (all chelonians, some squamates)
• viviparous (live baring)
• lecithotrophy (ovoviviparous) = egg in tract until hatching, hatch at partuition
• matrotrophy (viviparous) = livebearing = rare

Question 8

what is the function of FSH and LH in chelonians

Answer 8

same as mammals

Question 9

what is the reproductive endocrinology in squamates

Answer 9

• 1 gonadotrophin
• FSH like compound
• no LH equivalent

Question 10

what is the function of oestrogen in reptiles

Answer 10

• yolk development
• high early in season for seasonal breeders

Question 11

what is the function of progesterone in reptiles

Answer 11

• high during gestation
• high after. (+/- at) ovulation

Question 12

list breeding stimuli in reptiles

Answer 12

• temp change
• humidity
• day length
• presence of mate (induced ovulators)
• environmental topography (nesting areas)

Question 13

what is follicular stasis

Answer 13

• follicles produced, not ovulated
• accumulate, inflammation, infection, rupture and leakage
• caused by inappropriate diet/husbandry, lack of brumation/hibernation, lack of mating presence, stress, illness

Question 14

outline male fish reproductive anatomy

Answer 14

• paired intra-abdominal testes
• sperm carried by ductus deferens to: urinary bladder, common urinary duct, genital pore
• fish semen = milt

Question 15

outline female fish reproductive anatomy

Answer 15

• gymnovarian = oocytes into coelom (oviduct remnants) = salmonoids and sturgeons
• cystovarian = ovarian ducts = many bony fish species

Question 16

outlines the stages of reproduction in female fish

Answer 16

Question 17

what is the breeding cycle in fish

Answer 17

• 4 week to many years
• some continuous spring and summer
• some once a year/ many times a year
• some once in life (pacific salmon)

Question 18

outline reproductive endocrinology in fish

Answer 18

Question 19

list reproductive modes in the fish

Answer 19

• simultaneously both biologically male and female
• switch M to F or F to M
• parthenogenesis

Question 20

how do you determine sex of fish

Answer 20

Question 21

list environmental effect on fish reproduction

Answer 21

• photoperiod
• temp
• presence of opposite sex
• currents/tides
• proximity to spawning area