Effect of pipping rate and hatching nature on the development of ostrich chicks

Abstract

High embryonic mortality is concerning because of the effect on commercial ostrich farming. The number of viable chicks can be improved by appropriate interventions in the hatching chicks. Data from 2 683 fertile eggs were collected from the commercial, pair-bred ostrich flock on the Oudtshoorn Research Farm, South Africa, with 169 chicks being reported. Fertile eggs were randomly divided into three groups on days 41, 42, and 43 of incubation. There were four treatments: hatchlings that reached climax and broke free from the eggshell themselves (T1), hatchlings that were assisted to reach climax at the first signs of external pipping (T2), hatchlings that were removed from the eggshell at the first sign of external pipping (T3), and eggs that pipped internally after 43 d but failed to pip externally were cracked (T4). Clinical measurements (heart rate, body temperature, and oedema) were taken at hatch. The chicks were weighed for 7 d and then on days 28, 84, 147, 227, 300 and 365. Chicks that were assisted after internal pipping took longer to hatch. The heart rate of 115 beats per minute (bpm) for chicks hatching on their own was lower than the 132 bpm recorded for the other treatment groups. Up to day two after hatching, a decline in chick weight of ~4% was found. Chick weight increased from 0.85 kg to 1.11 kg in the first week. At 147 d, body weights between treatments were 12.6% higher for the chicks hatching on their own compared with the chicks where the eggshell was cracked, and 24.6% higher for chicks where the eggshell was removed after external pipping. Chicks benefitted by climaxing themselves, but for chicks struggling to hatch, this study provides guidance to hatchery operators on the specific stages where monitoring and assistance is important to improve hatchability.