USE OF SUPPLEMENTATION OF PROBIOTIC WITH DIFFERENT LEVELS OF CITRIC ACID AS PROMETER FOR PRODUCTIVE PERFORMANCE OF LAYING HENS

Abstract

This study aimed to evaluate using of feed supplementation of probiotic with
different levels of citric acid as a promoter for productive performance of
Lohmman Brown layers. Field experiment continued for five months. One
hundred and ninety five laying hens at 20 weeks age were reared equal numbers
in 15 floor pins, area of each one were 1.5 × 2 m by 13 hens per pin, and distributed
randomly into 5 equal treatments (3 replicates per treatment). First treatment was
fed a standard diet without supplementation as control, second treatment was fed a standard diet with probiotic 0.25%, third treatment was fed a standard diet with
citric acid 0.3%, while fourth and fifth treatments were fed a standard diet with
probiotic 0.25% and different levels of citric acid 0.3 and 0.45% respectively.
The results showed an improvement in the productive performance of birds fed
with the probiotic and citric acid, since it got significantly higher (P<0.05) in each
of egg production (Hen Day%), egg mass, feed intake, and food conversion factor
compared with control group. This effect has been enhanced for addition
treatments on the productive performance when fed birds from the addition
combination probiotic with citric acid compared with birds fed from each of the
individual added probiotic or citric acid. This improvement to productive
performance of treatment birds was a reflection of the improvement in both the
microbial balance of the gut, internal environment of the gut, tissue properties of
the gut and immune response. The counts of coliform and the counts of lactic acid
bacteria were increased significantly (P <0.05), while the counts of total bacteria
in the intestines not affected, whereas the pH of intestines dropped significantly.
Both the length of villi and depth of the crypts of the intestines increased
significantly, also the titer of antibody against Newcastle disease in birds fed the
probiotic and citric acid increased significantly compared with the control birds.