Carotenoids, vitamin A, and vitamin E concentrations during egg development in panther chameleons (Furcifer pardalis)

Abstract

Insects are known to be poor sources of preformed vitamin A, leading to the speculation that insectivorous species, including reptiles, may be able to convert carotenoid precursors to meet dietary requirements for this nutrient. This study was conducted to indirectly evaluate carotenoid and vitamin A metabolism in the panther chameleon (Furcifer pardalis). Eggs were obtained from females in Madagascar that were yolked either early or later in the breeding season, and carotenoid (α-and β-carotene, cryptoxanthin, lutein/zeaxanthin, and lycopene), vitamin A, and vitamin E concentrations were measured in egg contents in early, middle, or late embryonic development. An overall trend of decreased nutrient concentration as eggs matured (from egg period 1 (yolks) to egg period 3 (embryos)) was seen within both clutch groups. The season of clutch deposition was a significant influence on egg weight, α-carotene, and lutein/zeaxanthin concentrations, but on no other nutrients. Chameleon yolks contained considerably higher levels of carotenoids than levels previously reported from two viviparous lizard species, and β-carotene concentrations were of the same magnitude as reported in grazing tortoises. β-Carotene and β-cryptoxanthin were the predominant carotenoids in yolk and embryos, comprising about 95% of total carotenoids detected. Measurable concentrations of retinol at all stages of egg development in the chameleons suggests effective conversion from carotenoid precursors, with concentrations similar to those measured in other lizard eggs. Information from eggs obtained in native habitats may provide baseline data on nutrient interactions to improve and optimize captive dietary management; preliminary data suggest that micronutrient environments may vary over the protracted breeding season, with possible implications for embryo health and survival. Zoo Biol 21: 295-303, 2002.

Nutritional Metabolic Bone Disease in Juvenile Veiled Chameleons (Chamaeleo calyptratus) and Its Prevention

“…It is assumed that the concentrations in groups UV and No originated from low levels of vitamin A in untreated locust nymphs and potentially from the conversion of b-carotenes (not determined in this study) from the gut contents of these locusts. It has been suggested that insectivores may benefit from carotenoids that can be converted when required (39). Hence, a combination of preformed vitamin A and carotenoids may be optimal for veiled chameleons.…”

Egg Yolk Carotenoids in Relation to Habitat and Reproductive Investment in the Great TitParus major

“…Many oviparous species transfer carotenoids to the egg yoik (e.g., fish lAndo and Hatano 1991 ], reptiles [Dierenfeld et al 2002], and birds ISurai et al 1998]). Little is known, however, about the underlying mechanisms of maternal transfer of tbe pigments to the developing oocytes.…”

Do Hermann's tortoises (Testudo hermanni) discriminate colours? An experiment with natural and artificial stimuli

“…In particular, carotenoid pigments obtained from plants, algae, some bacteria and fungi (Gray 1996) perform important biological functions in animal tissues, such as the development of the intense pigmentation of many sexual ornamentations, or the enhancement of the antioxidant activity and the immune system (Aguilera & Amat 2007;Fitze et al 2007). Moreover, carotenoids are the essential precursors of vitamin A (Pitt 1971), which is involved in many vital functions as growth, vision, cell differentiation and spermatogenesis (Dennert 1984;Underwood 1984;Dierenfeld et al 2002).…”