33 PP
STUDY OF THE CAECAL MICROFLORA OF BROILER DUCKS: A COMPARISON WITH PUBLISHED DATA FOR CHICKENS.
Ridsdale, J.A.* and Corry, Janet E.L.
Dept. of Clinical Veterinary Science, University of Bristol, Bristol, UK.
Ducks, like other poultry, often carry high numbers of Campylobacter spp. and salmonellas. A number of studies have demonstrated that chicken caecal microflora can be used for 'competitive exclusion' (CE) of these pathogens from chicks. Chicken caecal preparations are not effective for the CE of these pathogens from ducks. This study was carried out with a view to development of a similar system in ducks.
The results of this study are summarised in the table, by comparison with results obtained by other workers for chicken caeca.
Log10 cfu g-1 of various bacteria in the duck and caecal contents
.|
|
Ducks |
|
Chickens |
|
|
|
This study |
Mitsuoka 1980 |
Salanitro 1974 |
Barnes 1986 |
|
Total bacteria |
11.3-11.9(11.7) |
10.7-11.1(10.9) |
10.8-11.2(11.0) |
10.0-11.0(10.5) |
|
Total obligates |
11.2-11.9(11.6) |
- |
10.7-11.1(10.9) |
- |
|
Total facultatives |
9.1-10.4 (10.0) |
- |
9.3-10.2 (9.7) |
- |
|
GNNSR |
9.6-10.4 (9.4) |
10.4-10.8(10.6) |
- |
9.0-10.0 (9.5) |
|
Clostridia |
9.1-9.6 (9.4) |
0.0 |
- |
9.0 |
|
Eubacteria |
6.5-7.8 (7.3) |
9.1-10.5 (10.2) |
- |
9.0-10.0 (9.5) |
|
Bifidobacteria |
5.4-6.7 (6.3) |
9.0-9.2 (9.1) |
- |
9.0 |
|
Lactobacilli |
9.4-10.0 (9.7) |
9.0-10.0 (9.5) |
- |
3.2-4.1 (3.6) |
|
Enterobacteria |
7.7-9.9 (9.5) |
6.6-9.4 (7.0) |
- |
- |
|
Streptococci |
9.0-10.2 (9.6) |
6.7-7.5 (7.1) |
- |
10.0 |
Key: GNNSR-Gram negative; non sporing rods.
Obligate anaerobes dominated duck caecal microflora whereas only 2% were facultative anaerobes. Gram negative non-sporing rods predominated in both ducks and chickens. Eubacteria and bifidobacteria were found in higher numbers in chickens. By contrast, numbers of Enterobacteriaceae and streptococci were higher in ducks. These differences might account for the ineffectiveness of chicken caecal microflora as CE products for ducks.
References.
Barnes, E.M. (1986) In Bacteria in Habitats Other Than Man. pp 225-228.
Oxford, UK: Blackwell Scientific Publications.
Mitsuoka, T. (1980) In Proceedings of the International Symposium of
Anaerobes. pp 53-57. Tokyo, Japan: Nippon Merck-Banyu.
Salanitro, J.P et al (1974) Applied Microbiology 27: 678-687. BODY