Maternal effect influence phenotypes variations on eggs and progeny of Caiman latirostris

LEIVA, P. M. L.; PIÑA, C.I.; SIMONCINI, M. S.; LABAQUE, M.C.

Chetumal

Congreso; XXVI Working Meeting Crocodiles Specialist Group - UICN; 2022

Crocodiles Specialist Group - UICN

In oviparous animals,mothers can influence offspring phenotypes through resource allocation to eggs.Maternal effects mediated by egg´s quality may affect offspring performance,and mothers may adjust egg traits according to environmental influences. We haveevaluated influence of climatic variables and body and physiological conditionof Caiman latirostris reproductivefemales, and their relationship with eggs chemical characteristics (yolk Fatty Acids,FA), hatching success and hatchling phenotype. Fourteen females were captureddefending their nests. We recorded: body (Scaled Mass Index) and physiological conditions(muscle and blood samples). For every nest, one group of eggs was derived forchemical analysis and other for incubation. Precipitation and temperature ofMarch-April (previous reproductive season) and September-October-November-December(prior to the oviposition) were obtained. We found that eggs offemale with better body condition, presented higher proportion of C20:4, totalpolyunsaturated (PUFA) and low 18:2, and were associated with higher hatchingsuccess. Low PUFAs percentage in female's muscle were relatedto better female body condition and offspring´s weight, giving indications thatthese FA were mobilized and invested by the female in the egg. Also, egg´s C18:2 content was positively correlated withthat of the maternal muscle tissue, which in turn is positively associated to minimumtemperatures of September. These temperatures are negatively associated withlocal rainfall of months in which vitellogenesis occurs, indicating thatfemales would be consuming dietary items that contribute high content of this essentialFA. Plasma PUFA´s profile was affected by December precipitation probably dueto female´s consumption of determined prey during different climaticconditions. Therefore, it would be advantageous for maternal investment, yearswhere the local rainfall of the months in which vitellogenesis occurs is abundantbecause they have access to a greater diversity of prey items, to be able toinvest quality resources to their progeny favoring reproductive success.