Reptile & Bird Reproductive Anatomy & Physiology PDF

9/11/24 INTRODUCTION TO 0/21 AVIAN & REPTILE REPRODUCTIVE ANATOMY & PHYSIOLOGY 0 Aims & Objectives 1/21...

9/11/24 INTRODUCTION TO 0/21 AVIAN & REPTILE REPRODUCTIVE ANATOMY & PHYSIOLOGY 0 Aims & Objectives 1/21 Know the gross reproductive anatomy of male and female birds & reptiles Appreciate the factors that stimulate reproduction (environmental, nutritional, owner) Understand the concept of temperature-dependent sex determination in chelonians and lizards Know the differences between oviparous (egg production, laying, incubation) and viviparous (live-birth) 1 1  9/11/24 2/21 BIRDS 2 Male Reproductive Anatomy 3/21 DNA sexing of monomorphic species Testis (left and right) Vas deferens Cloaca 3 2  9/11/24 Female Reproductive Anatomy 4/21 DNA sexing of monomorphic species a. Ovary (typically left only) b. Infundibulum c. Magnum d. Isthmus e. Uterus – Shell gland f. Vagina g. Cloaca 4 Seasonal Reproductive Cycle 5/21 Most psittacines breed early spring to summer – Photoperiod (artificially elongated daylength) – Presence of a mate (or owner!) – Nutrition (esp high caloric/seed diets) – Appropriate nesting area – Appropriate temperature, humidity. 5 3  9/11/24 Egg Production 6/21 Calcium storage (estrogen) – mobilized for shell production (PTH) Ovulation (2-4 eggs/clutch) – ↑ LH surge, ↑ estrogen, – fertilization in the infundibulum – female is heterogametic (ZW) Progesterone – inhibits further ovulation – causes incubation behavior Brood patch (featherless) Crop milk (prolactin). 6 7/21 REPTILES 7 4  9/11/24 Female Lizards 8/21 Ovaries (paired, mid-dorsal coelom near adrenals) Oviducts (thinly walled). 8 Male Lizards 9/21 Testes (paired, mid-dorsal coelom near adrenals) Renal sexual segment (seasonal proliferation of distal convoluted tubules) Paired hemipenes. 9 5  9/11/24 Lizard Sex Identification 10/21 Head conformation Pores (femoral, anal) Male Hemipenal bulges. Female 10 Female Snakes 11/21 Ovaries (paired and elongated, 56-85% SVL, 20% BL) Oviducts (thinly walled). 11 6  9/11/24 Male Snakes 12/21 Testes (paired, mid-dorsal coelom near adrenals) Renal sexual segment (seasonal proliferation of distal convoluted tubules) Paired hemipenes. 12 Snake Sex Identification 13/21 Tail length – Males have longer tails Hemipenal probing – Males probe to a depth of 6-14 subcaudal scales (female < 6). 13 7  9/11/24 Female Chelonians 14/21 Ovaries (paired and near kidneys when small, when large can occupy large area) Oviducts (more muscular than squamates, hence more responsive to oxytocin). 14 Male Chelonians 15/21 Testes (paired, caudodorsal coelom near adrenals/kidneys) Single phallus. 15 8  9/11/24 Chelonian Sex Identification 16/21 Shell (males concave, females flatter) Tail length (males have longer tails, distal vent) Some aquatic males have longer nails. 16 Courtship & Intromission 17/21 Courtship – Male induced trauma? Cloacal alignment Internal fertilization. 17 9  9/11/24 Oviparous (Egg Production) 18/21 All Chelonia Many lizards & snakes – Egg incubation Temperature (26 - 33oC) Humidity (90-100%). 18 Temperature Dependent Sex Determination 19/21 Most chelonians éo C = female, êoC = male Few lizards (snakes?) éo C = male, êo C = female. 19 10  9/11/24 (Ovo)viviparous 20/21 Some lizards & snakes – Internal incubation of unshelled eggs – Female husbandry critical Basking area temperatures Seclusion. 20 Aims & Objectives 21/21 Know the gross reproductive anatomy of male and female birds & reptiles Appreciate the factors that stimulate reproduction (environmental, nutritional, owner) Understand the concept of temperature-dependent sex determination in chelonians and lizards Know the differences between oviparous (egg production, laying, incubation) and viviparous (live-birth) 21 11