EFFECT OF SOME BIOLOGICAL ADDITIVES ON THE PERFORMANCE
AND THE INTESTINAL HISTOPATHOLOGY AND MICROBIAL
POPULATIONS IN BROILER CHICKENS
Mohamad Elsayed Abd ElMagid Mohamad Elmasry
ABSTRACT
Over the past 50 years, there has been increasing amount of antibiotics used
prophylactically and as growth promoters in poultry production, but multiple
antibiotic resistance of pathogenic bacteria and links between risk of zoonotic
diseases infections on human health and growth promoting antibiotics usage in
poultry livestocks make it necessary to look for alternatives to antibiotics use in
poultry production. In the present study indigenous bacterial isolates originated from
intestine of a healthy adult chicken (Bacillus cereus/ thuringiensis A and Bacillus
pumilus B) and exogenous micro-organisms like Saccharomyces cerevisiae F25, tea
fungus (Kombucha beverage and cellulosic mat), Epicoccum sp and spent mushroom
(Pleurotus spp), were used as biological additives (pro- and pre-biotics) in
comparison with the antibiotics additives for Avian 43 broiler chickens.
The obtained results showed significant increase in the final live body weight of
chicks treated with the two bacterial isolates (B. cereus and B. pumilus) and the other
biological treatments numerically increased live body weight and weight gain
compared with control treatment. The best treatment for stimulation appetite and
therefore increased feed consumption were recorded in cases of Bacillus cereus and
Bacillus pumilus treatment but all treatments had feed conversions better than that of
the control treatment and the incident mortality could be as a normal mortality rate.
Although the effects of biological additives on blood constituents varied, negative
effects couldn't be detected. The total count of coliform bacterial groups (pathogenic
bacteria) decreased in the intestine of birds treated with some of the indigenous and
exogenous microbial materials, whereas, the lactobacilli bacterial group (beneficial
bacteria) increased. The microscopically examination of intestinal cross sections
revealed improvement in the immune related intestinal structures (mucus secreting
glands and epithelial lining intestinal villi) and showed no histopathological features
in birds treated with some biological additives, while macro and micro gametes of
Eimeria coccidia and periglandular edema were observed in the intestines
histopathological examination of birds treated with antibiotics.