Impact of dietary cation anion difference on leg deformities and growth performance of broilers

الملخص EN

The present study was conducted to evaluate mainly the effect of diff-erent levels of dietary electrolyte balance (DEB) or dietary cation anion difference (DCAD) more or lower than the literature suggested levels, on the leg deformities and moralities of broilers in the different growth stages.

Moreover, to study the relation between electrolyte balance and growth performance, bone mineralization and blood concentration of these minerals.

So, live body gain, feed intake, feed conversion, water intake and water / feed ratio were calculated.

Also, serum and bone of legs were analyzed for Ca, P, Na and K to show the effect of different DCAD elements content on these minerals concentr-ation in serum and bone construction.

The effect of DCAD levels on kidney were demon-strated through histo-pathological examination.

The study has been carried out using 200 one-day-old commercial Hubbard chicks.

The chicks were allotted into 5 experimental groups each of 40 birds and reared under the recommended health program in separate pens.

The chicks were fed on basal diet calculated to provide DCAD 229 and 196 meq / kg diet for starter and grower diets respectively (NRC, 1994).

The other 4 groups were fed 2 lower (181, 130 and 150, 96) and 2 higher (321, 280 and 300, 247), levels of DCAD than control in each growth stage.

The results showed that when DCAD values deviated toward downward of the control, the body weight gain showed significant decline in cumulative body weight gain, feed intake and inefficient feed utilization as compared with other experimental groups.

The leg deformities were increased by the age advancement in the groups fed low DCAD and began to occur by the end of the starting period and aggravated by the end of the experimental period.

Significant alteration in the measurements of affected tibia (length and thickness), ash % and Ca % of ash in the starting period, ash %, Ca %, and P % in the grower period were demonstrated.

Also, the serum content of minerals showed a significant decrease in both Ca and P levels in the starting period and in Ca level in grower period.

There was bad effects of manipulating higher DCAD on the histo-pathological examination of the kidney began in the starter period and aggravated in the grower period, consequently affect the mortality rate for the two higher DCAD levels at the end of the experiment.