EFFECT OF SYNBIOTIC ON INTESTINAL HISTOMORPHOMETRY AND GROWTH RATE IN QUAILS, EXPERIMENTALLY INFECTED WITH FIELD STRAIN OF SALMONELLA GALLINARUM

Abstract

This study was planned to investigate the effect of synbiotic on intestinal
histomorphometry and the growth rate of quails experimentally infected with a field strain of
Salmonella gallinarum. Day old Japanese quails (120), with an average body weight of 6.09±1.1 g,
were randomly assigned into 4 groups A, B, C, and D. Quails of groups A and B were given synbiotic
on a daily and weekly basis respectively, along with challenge while group C was negative control and
group D was the positive control group. A total of 60 organ samples of the intestine were collected
from apparently healthy and freshly dead quails respectively to isolate the field strain of Salmonella
gallinarum. Bacterial isolation and molecular identification were performed in accordance with
laboratory diagnostic culture techniques and PCR. Results from the current study indicate that
nonantibiotic feed additives such as synbiotics boosted the gut histomorphometric parameters
including the villus height, villus width, and crypt depth under the challenge of Salmonella gallinarum.
There was a significant increase in all these parameters due to synbiotic feeding except for the negative
control group which showed the lowest values. On day 21, DD achieved a maximum villus height of
636.88 ± 65.93b µm in the duodenal mucosa, whereas, maximum villus width of 182.01 ± 15.40c µm
in duodenal mucosa was achieved by group AA. Maximum villus height of 276.89 ± 21.16b µm and
crypt depth of 26.66 ± 1.15a µm in jejunum mucosa were recorded in group AA. Statistical results by
using the technique of one-way ANOVAs indicated that there was a significant increase in
morphmetric parameters of duodenal and jejunum mucosa in the groups fed synbiotic as compared to
the negative control. Hence results illustrate that there is an overall increase in histological parameters
of duodenal and jejunum mucosa in the groups fed synbiotic as compared with the negative control
group. This study supports the beneficial effects of synbiotic on intestinal health and the growth rate of
Japanese quails by improving FCR.