التركيب الوراثي و مصدر البروتين و أثرهما في الأداء الإنتاجي لفروج اللحم

الملخص EN

The purpose of this experiment was to quantify the responses of three broiler strains of different genotypes to two protein sources (animal and vegetable) on performance and carcass weight.

Nine hundred one- dayold broiler chicks of three strains (Cobb 500 ,Ross308 and Hubbard) were placed in 18 floor pens, three hundred chicks of each, at a rate of 50 chicks per pen, to form six treatments.

The chicks were raised up to 56 days.

Feed and water were available ad libitium.

At the end of the growing period (28 d), Cobb exhibited priority in growth parameters as body weight and growth rate on both Ross and Hubbard strains.

At the age of 42 days , significant differences (P < 0.05) were obtained in terms of performance of strains.

Over all, Cobb and Ross birds had higher body weights ; i.

e.

2418, 2440 vs 2170 gm for Hubbard, higher relative growth rate ; i.

e.

129.5, 132 and 129.2 and higher carcass weights i.

e.

1710, 1729 and 1484 gm for these strains, respectively.

However, at day 56, Hubbard strain showed an improvement in body weight and growth rate, to be at the mark of other strains.

Economical efficiency was greatly affected (P < 0.05) by strains for both Cobb and Ross over Hubbard.

But there was no effect of protein source on the economical efficiency at various ages.

It was concluded that Cobb and Ross strains were better than Hubbard.

The 42 day age is a favorable age for broiler marketing.