- A preliminary study was conducted to establish baseline data for emu artificial egg incubation and emu chick growth and management. Three experiments examined factors affecting hatchability of emu eggs that occur prior to and during artificial incubation. Characteristics analyzed were egg storage duration, hen age, egg weight, egg index, shell thickness, incubation temperature, incubator type, and egg weight loss. The six treatments among the three incubation experiments consisted of two AVN incubators with temperatures maintained at 36.0 C and 35.8 C, and four Jamesway 252 incubators maintained at 36.0 C, 36.6 C, 36.5 C, and 36.7 C. Three subsequent experiments involved six treatments with hatched chicks to test the effects of diet and pen size on chick weight gain, and growth of the beak, middle toe, and tarsometatarsus up to eight and ten weeks of age. Sand, grass clippings, and pine shavings substrates were also tested.
Analysis of duration of egg storage indicated that an increase in pre-incubation storage time was associated with a decrease in hatchability. The highest percent hatch
(63.8%) occurred for eggs held ≤7 days and decreased for each additional week stored.
Analysis revealed evidence that as emu hen age increased, fertility increased (p<0.05). Also, as hen age increased, egg size increased (p<0.05). Age often did not influence (p>0.05) egg index or shell thickness. There was no indication that egg index had an effect on hatch. An inverse relationship was observed between hatchability and egg shell thickness. Higher incubation temperatures were associated with a decrease in hatchability. Temperatures ≤36.0 C resulted in an average hatchability of 64.3%, while temperatures ≥36.0 C resulted in only 47.2%. Incubation temperatures ≤36.0 C were observed to increase chick quality compared to temperatures >36.0 C. Eggs having weight loss of 11%-14.9% during incubation had higher percentage hatch than eggs with losses out of this range. The pattern for embryonic mortality was observed to be similar to the pattern in other domestic avian species; high mortality peaks at the beginning and end of incubation. However, a higher than expected mortality occurred between the two peaks.
Chicks fed a 21.4% protein broiler starter diet (BS) had higher weight gain (p<0.05) than chicks fed a 20.1% protein chick starter diet (CS). Feed conversion among chicks consuming the BS was significantly better (p<0.05) than the chicks consuming the CS. In a 2 X 3 factorial design experiment, chicks were raised in two different pen sizes, 0.9 m X 3.0 m and 1.8 m X 11.0 m, and fed three different commercial diets; an 18% protein all-in-one diet (AIO), a 23% protein emu diet (EMU), and a 28% protein turkey-gamebird starter diet (TG). Chicks showed no evidence (p>0.05) of interaction between pen size and diet for weight gain, feed conversion, or growth of the beak, middle toe, and tarsometatarsus. However, chicks fed EMU consumed significantly more feed (p<0.05) than chicks fed TG. Pine shavings substrate was determined to be the least labor intensive and provided the best footing for the chicks among the three substrates tested.
According to this investigation, for farmers to achieve maximum production for artificial incubation of emu eggs, they should use breeder hens ~4 years old, store eggs no longer than 7 days, and incubate eggs at temperatures ranging from 35.5 C-36.0 C. Until nutrition requirements are established for emu, there is no advantage to feeding emu chicks through 10 weeks of age a commercial emu diet compared to other commercial domestic bird diets.