Egg storage period and weight effects on hatchability of ostrich (Struthio camelus) eggs

Abstract

We studied the affects of storage period and egg weight on the hatchability of 314 ostrich (Struthio camelus) eggs. Eggs were stored at 20 degrees C and 65% RH before incubation at the Poultry Research, Teaching and Extension Center at Texas A&M University (College Station, TX). Eggs were classed by storage period (< or = 5, > 5 < or = 10, > 10 < or = 15, or > 15 < 24 d) and egg weight (< or = 1,450, > 1,450 < or = 1,650, or > 1,650 g) to determine the influence of storage period and egg weight on hatchability, egg weight loss, incubation period, and absolute and relative chick weights. Eggs were incubated at 36.5 to 37.0 degrees C and 25% RH through 38 d of incubation and 36 degrees C and 30% RH thereafter. Mean egg weight loss was greater from eggs of the longest storage period group (> 15 < 24 d) at 21 or 38 d when compared with eggs of the shorter storage periods, but there were no differences at 7, 14, or 28 d among all storage period groups. Mean hatchability was higher in eggs stored < or = 10 d than eggs stored > 15 < 24 d, but hatchability of eggs stored >10 < or = 15 d was not different from eggs stored < or = 10 d or > 15 < 24 d. Incubation period was longer, and absolute and relative weights were higher in eggs stored >15 d than was observed in eggs stored < or = 15 d. Negative correlations were detected between egg weight and moisture loss at 38 d (-0.55) and between hatch time and moisture loss (-0.25). Hatchability was higher in small eggs than medium eggs (< or = 1,650 g). A positive correlation was observed between chick and egg weights (0.84). The results indicated that storage period and egg weight affected egg weight loss. Our results suggested that the most effective storage period was less than 15 d to maintain hatchability for ostrich eggs when incubated at 36.5 to 37.0 degrees C with 25% RH.