Abstract
The effects of in ovo feeding of L-Glutamine (GLN) at 17th day of incubation on hatchability traits, hatching time and chick weight at hatch (CWT and CWT%, expressed as an absolute value and as a percentage of egg weight, respectively) of Ross meat-type breeder eggs were studied at 26 and 32 weeks of age in trials 1 and 2, respectively. The treatments were a non-injected control, a positive control where saline was injected or saline with GLN at 5, 7.5 and 10 mg/egg. In ovo feeding of GLN did not influence hatchability traits, CWT, CWT% and hatching time. In ovo feeding of 10 mg GLN/egg increased percentage of hatched chicks at 468 h of incubation and reduced percentage of hatched chicks at 492 h of incubation when compared with those of the control treatments. Age of birds did not influence hatchability traits and percentages of hatched chicks at 468 and 492 h of incubation and CWT%. Eggs produced at 26 weeks of age had lower weight, percentage of hatched chicks at 504 h of incubation, hatching time and CWT when compared with those produced at older age. It is concluded that in ovo of up to 10 mg GLN/egg at 17th day of incubation of layer-type breeder eggs did not influence hatchability traits, chick weight at hatch and hatching time and eggs produced at older age had higher egg weight, chick weight at hatch and hatched later than those produced at younger age.