ABSTRACT
(1) Survival and weight gain of farmed Greater Rhea (Rhea americana) chicks reared by the adult males that adopted them were compared with those of chicks reared under an artificial intensive system. (2) Both variables were periodically recorded up to the age of 3 months. Gompertz growth curves were fitted to individual growth data using the average adult weight of this population as asymptote. (3) No significant differences in survival rate were detected between systems (adoption=47%, intensive=43%). However, during the first half of the breeding season (mid-spring to mid-summer), the growth rate of adopted chicks (0.01481) was higher than that of intensively reared chicks (0.01296). (4) The adoption system may be more effective in terms of growth, and is probably more efficient in cost/effectiveness than the artificial intensive technique most frequently used. Adoption by males has additional advantages, such as a correct imprinting of the chicks and the selection of more capable individuals. Therefore, it should be used not only commercially but also in conservation projects where individuals are released to the wild.
Subject(s)
Animal Husbandry/methods , Behavior, Animal , Rheiformes/physiology , Aging , Animals , MaleABSTRACT
1. Eggs from 4 farmed populations of Lesser Rhea (Pterocnemia pennata) were studied to determine their physical and chemical characteristics. 2. None of the physical variables (weight of whole egg, yolk, albumen and shell; proportion of yolk based on egg content; proportion of shell based on entire egg weight; volume; density) showed significant differences between populations. 3. Among chemical variables, moisture, both saturated fatty acids (palmitic 16:0 and stearic 18:0), one monounsaturated fatty acid (palmitoleic 16:1), and one polyunsaturated fatty acid (arachidonic 20:4), did not differ between populations, whereas other variables (protein, lipid and ash contents; fatty acids: oleic 18:1, linoleic 18:2, linolenic 18:3; PUFA; PUFA/SFA; cholesterol) differed significantly.
