Effect of age and body weight of Greater Rhea (Rhea americana) females on egg number, size and composition

LÁBAQUE MC, MARTELLA MB, MAESTRI DM, HOYOS L, & NAVARRO JL.

BRITISH POULTRY SCIENCE

TAYLOR & FRANCIS LTD

Año: 2010 vol. 51 p. 838 - 846

0007-1668

1.      A study was conducted to evaluate how body weight and age of each female are related to the number and physical and chemical characteristics of the eggs it produces throughout a breeding season in a captive-bred population of Greater rheas (Rhea americana). 2.      Reproductive performance of 15 females of three age classes (5 individuals per class) was monitored; female body weight was recorded before laying onset. All the eggs laid (produced by the 12 females) were collected and identified, and different morphometric variables, percentage of components, and fatty acid composition were determined.  3.      The earlier the female started laying, the longer the laying period and the greater the overall number of eggs produced. The onset of laying in turn seemed to be related to the attainment of high body weight. 4.      Except for length, the values of the morphometric variables of the egg and unsaturated fatty acids (palmitoleic, oleic and linoleic) increased with female age. 5.      High body weight was associated with low palmitic and palmitoleic fatty acids, and high linoleic, linolenic and total unsaturated fatty acids. 6.      Live weight and age of Greater rhea females would have largely determined several physical and chemical characteristics of the eggs they produced.