The Effect of Feed Supplemented with Different Sodium Bentonite

 

Treatments on Broiler Performance

Bentonites are excellent aflatoxin binders due their

affinity for polar substances. The in vitro experiments

conducted by the Pakistan Council of Scientific and

Industrial Research Laboratories, Lahore, showed that

bentonite bound 90% of the aflatoxins present in feed

and made them effective and un-absorbable from the

gastrointestinal tract (2). The improvement in weight

gain observed in the present study could have been due to

the presence of NaB in the diet, which might have

increased feed retention time in the gut of the chicks,

thus subjecting the nutrients to enzymatic action for quite

a long time, or could have been due to the action of

bentonite on the enhanced digestibility of certain

nutrients. These results are in agreement with previous

studies (3,5,14,15) in which NaB significantly improved

body weight gain in broiler chicks.

Increased feed intake in all treatment groups could be

attributed to the presence of NaB in the rations, which

can act as a pellet binder and improve not only pellet

quality, but also feed intake. These results are supported

by previous research (4,14) that found NaB increased

feed intake and growth performance in broiler chicks.

The high weight gain and feed consumption in the birds

fed 0.5% and 1.0% NaB + 0.5% and 1.0% AA,

respectively, indicates that NaB’s qualities can be further

enhanced by AA; however further studies are required to

investigate the relationship between NaB and AA.

The non-significant differences between the PER

values of the different experimental groups may have

been due to the fact that NaB mainly acts on feed when

in the gastrointestinal tract. This hypothesis can be

further supported by our protein retention data

indicating that the presence of bentonite prolonged feed

passage time and improved nutrient metabolism. The

protein retention results of the present study are in

agreement with previous findings (2) of improved energy

and protein utilization in the presence of bentonite.

Differences between ileal and excreta digestibility in the

present study clearly demonstrate that amino acid

metabolism by hindgut microflora in chickens may be

substantial and that digestibility measured in the terminal

ileum is a more accurate measure of amino acid

availability than that measured in the excreta.

It can be concluded from this trial that NaB alone at

the 0.5% level or treated with 0.5% or 1.0% AA can be

incorporated into broiler rations for improving growth

and feed utilization. Although no statistically significant

differences were observed in PER values, PER values

increased when birds were fed rations containing 0.5%

and 1.0% NaB + 0.5% and 1.0% AA , respectively

(treatments F and G). Thus, it can be suggested that NaB

+ AA improved protein digestion. These results are

further supported by the significantly increased protein

retention values observed in the birds fed rations

containing 0.5% and 1.0% NaB + 0.5% and 1.0% AA,

respectively.