Toxo-pathological effects induced by urea in broiler chicks

Abstract

Sixty, day-old, chicks were reared up to 3 weeks of age and then randomly divided into 4 equal groups (3 treated and one control group). Urea (46 % nitrogen) was added to the grower-finisher ration of the treated birds at levels of 1% , 3% and 5% (groups I, II & III respectively). Feed and water were available ad libitum for all birds over the time of experiment. At days 7, 20 and 30 post exposure, 5 birds from each group were weighed, bled and sacrificed. All birds spontaneously died during the experiment were also necropsied. Haematological parameters (RBCs, WBCs counts, PCV and Hb), biochemical variables [urea, glucose, uric acid, alkaline phosphatase; (ALP) and lactate dehydrogenase; (LDH)] and body weight gain were assessed. The encountered pathological changes were described. The obtained results indicated that: (1) decrease in RBCs, WBCs counts, PCV and Hb, (2) increase in ALP, LDH, urea and uric acid, while glucose level was decreased. (3) decrease in body weight gain in all treated birds. There were significant pathological changes in kidneys, heart, liver and lungs of the treated birds. It was concluded that addition of urea to poultry feeds to replace the more expensive protein-nitrogen has serious consequences which affect the health condition and weight gain of birds.

Pathological study on urea utilization by poultry

“…There were cartilaginous and osseous nodules among the pulmonary tissue. These microscopic findings completely agreed with Abdou et al (2006); Elkhawaga (1999) who reported similar lesions in chicks. Moreover, the lung showed emphysema and air alveoli of the lung tissue showed focal epithelization of the lining epithelium with dilatation and desquamation of the epithelial layer.…”

“…Urea has been used as a cheap protein substitute in the poultry feed (Pervaz et al, 1993). However, toxicity can occur when chicks are kept on urea treated feed (Jabbar, 1994;Pervaz, 1994;Abdou et al, 2006). Recently, commercial pet food was adulterated with melamine (Brown et al, 2007).…”

Performance and Some Physiological Indices of Broiler Chicks Fed Urea-Containing Grower Diets

“…The decreased FI and BWG of broiler chicks fed the urea-containing diets in the present study is in harmony with the results of Pervaz et al (1994, Javed et al (1995, Abdou et al (2006) and Islam et al (2006) who reported significant reductions in growth performance of broiler chicks fed diets containing between 2 to 6% urea. However, Das (1997) observed no adverse effects of feeding urea up to a concentration of 15 g/kg in the diets on the growth of chicks.…”

“…**: Significant at P≤0.01. The increase in blood urea level of broilers due to feeding ureacontaining diets, observed herein, has also been reported by several investigators (Bruckental and Nitsan, 1981;Karasawa and Umemoto (1993;Nagalakshmi et al, 1999;Abdou et al, 2006;Al-Ankari, 2006;Islam et al, 2006). Similar observations were reported when urea, as a NPN source, was included in rabbit (Ismail et al, 1999) and swine (Kornegay et al, 1970) diets.…”

“…On the other hand, some studies suggested that broiler chicks fed dietary urea at a level of 1% exhibited an increase in both live body weight and carcass weight (Pervaz et al, 1994), whereas levels beyond 4% had adverse effects on heath and performance of broilers (Pervaz et al, 1994 and1996;Javed et al, 1995). Recently, Abdou et al (2006) investigated the deleterious effect of adulteration of broiler rations by addition of urea at inclusion levels of 1, 3 and 5%. They found that birds fed the experimental diets, particularly which contained 3 and 5%, exhibited lower body weight gain and feed intake and poorer feed conversion compared with their control group.…”