Frequency of Occurrence of Physical Defects in Turkey Poults / Częstotliwość występowania wad budowy piskląt indyczych

Abstract

The objective of this study was to determine poult quality in the first breeding season of turkeys. The study was conducted over a 24-week laying season of white broad-breasted Big 6 turkeys. Starting from the first week of laying, at three-week intervals, 504 eggs laid on the same day were weighed and the percentages of eggs weighing 70 to 100 g and more than 100 g were calculated. Results from the 21st week of laying season were not used due to failure of ventilation equipment. Each egg was visually inspected to determine the percentages of eggs with normal shell structure, rough-shelled eggs and eggs without shell pigmentation. Nine incubation cycles were carried out. Egg fertilization rates and hatch rates were determined. At the end of each incubation cycle, poults were weighed individually and divided into morphologically normal and morphologically defective. The latter were further subdivided into weak poults with poor motor skills, poults with abnormal feathers, eyes, legs and umbilicus, and poults with unabsorbed yolk sacs. Eggs with weight exceeding 100 g accounted for 17.9% and 46.6% of the analysed eggs at 12 and 24 weeks of the laying season, respectively. In week 12, eggs without shell pigmentation accounted for 8.3%. In week 24, the percentage of rough-shelled eggs was 6.7%. Most poults with physical defects hatched in weeks 1 and 3 of the laying period (65.67% and 76.84%, respectively). Weak poults with poor motor skills accounted for 0.2-2.5% of the examined birds. Wet feathers were noted in 0.9% to 4.1% of poults over the laying season. Leg abnormalities were observed in 6.5% to 7.8% of poults. Eye defects were encountered least frequently. In 41-70% of poults long black scabs were visible on their navels, and umbilical vessels were long. Unabsorbed yolk sacs were noted in 0.5% to 3.2% of poults.