Effect of Temperature During Incubation and Brooding on Broiler Chickens

organs;incubation;brooding;temperature;broiler

Leksrisompong, Nirada ; Jerry W. Spears, Committee Member,Vern L. Christensen, Committee Member,John T. Brake, Committee Chair,Leksrisompong, Nirada ; Jerry W. Spears ; Committee Member ; Vern L. Christensen ; Committee Member ; John T. Brake ; Committee Chair

University:North Carolina State University

关键词: organs;    incubation;    brooding;    temperature;    broiler;   

Others  :  https://repository.lib.ncsu.edu/bitstream/handle/1840.16/1910/etd.pdf?sequence=2&isAllowed=y

美国|英语

来源: null

【 摘 要 】

A series of experiments was conducted to study the effects of the interaction between incubation and brooding temperature on chicks and early broiler performance. Braun Thermoscan infrared thermometer methodology was used to measure internal egg temperature. Ross 344 x 308 broiler hatching eggs were used exclusively and 53% relative humidity was maintained during incubation.During the first 13 or 14 d of incubation air temperature was 37.5-37.70C (99.5-99.80F) following which eggs were assigned to either a HIGH 39.5-40.60C (103.1-105.10F) or a NORMAL 37.7-37.90C (99.9-100.20F) temperature incubator (range varied by experiment). Six experiments, in various manners, measured the effects of incubation temperature, brooding temperature, sex, egg size, and all possible interactions on body weight (BW) on day of hatching (0 d) up to 28 d of age as well as relative weights of tissues and organs from 0 d to 21 d of age.Certain experiments measured feed consumption, BW, adjusted feed conversion ratio (AdjFCR), and deaths at 0, 2, 5, 7, 12, 14, 21, and 28 d of age.BW, heart, gizzard, proventriculus, and small intestines of chicks were decreased due to increased incubation temperature while the liver and yolk sac were increased. The proventriculus and small intestines were larger in females than in males.Small sized eggs produced chicks with smaller yolk sacs, and larger hearts and gizzards than average and large sized eggs.BW increased while heart and small intestines weights were decreased at 14 and 21 d by hot brooding.Feed consumption was decreased by increased incubation temperature at all ages but was increased by hotter brooding temperature during the 0-7 d period but decreased during the 7-14 d period. Hot-brooded chicks that had been incubated in the normal incubator consumed the most feed while cool-brooded chicks that had been incubated in the hot incubator consumed the least feed during the 0-2 and 0-7 d periods.BW was significantly decreased by increased incubation temperature up to 21 d. Cool brooding increased BW more for normal incubated chicks than did hot brooding at 7 d of age.By 14 d the high incubation-hot brooding chicks were smaller than all other groups while the normal incubated-cool brooded chicks were larger than all other groups. Males with a combination of normal incubation temperature and cool brooding temperature exhibited heavier BW than males with a combination of high incubation temperature with cool brooding temperature while brooding had less effect on males from hot incubation and there was little differentiation among the females at 14 d of age.AdjFCR was decreased (improved) by increased incubation temperature up to 21 d because the chicks did not eat. The AdjFCR was increased (worsened) by increased brooding temperature during 2-5 d and 0-7 d periods. Chicks from the high incubation temperature and brooded in a cool room had lower (better) AdjFCR than the other chicks.Mortality for the 0-7 and 0-14 d periods was significantly increased by increased incubation temperature.There was higher mortality for high incubated-cool brooded chicks during the 0-7 d period.Males at a cool brooding temperature exhibited a greater percentage mortality than females at 0-7 d.Elevated incubation temperature negatively affect embryo development and broiler performance up to 28 d of age. The problem could be reduced by hot brooding temperatures during the first days of life.However, hot brooding temperature decreased feed consumption and growth if continued for more than a few days.