Effect of strain, sex, and age on live body weight and relative weights of visceral organs in broiler Chickens

The study examined the effect of age, strain, and gender on chickens' body weight, carcass yield, and relative weight of some visceral organs. A total of ۲۲۴ day-old broiler chickens from two strains (Arian and Ross ۳۰۸) were randomly allocated into ۵۶ wire cages. Each cage contained ۴ broilers (two males and two females), resulting in ۲۸ replicate cages for each broiler strain. On four specific days of the rearing period (days ۱۰, ۲۴, ۳۲, and ۴۲), ۱۲±۲ male and ۱۲±۲ female chickens from each broiler strain were randomly selected, weighed, and then slaughtered. Then carcass yield, visceral organ weights, and the weight of different segments of the alimentary tract were determined on each slaughter day after evisceration. The findings indicated that females in both strains had a higher liver relative weight compared to males. The Bursa in the Ross ۳۰۸ was found to be significantly heavier compared to Arian only on ۳۲-day-old broiler chickens. Additionally, in ۲۴-day-old chickens of the Ross strain, the weight of the bursa was heavier than that in ۱۰-day-old chickens from the same strain (P<۰.۰۵), suggesting a stronger immune system development of Ross ۳۰۸ chickens during this age interval. The gizzard and jejunum relative weights were significantly higher in Arian strain than those of the Ross ۳۰۸ strain (P<۰.۰۵). It may be concluded that the lower body weights of the Arian chickens compared to Ross ۳۰۸ broilers were caused by limiting factors other than the disproportionate morphometric growth of the digestive tract at macroscopic level.

کلیدواژه ها:

Arian ، Breeding ، Carcass ، Ross ۳۰۸ ، Small intestine