Western
Meeting of Poultry
Clinicians and Pathologists
|
Clinicians and Pathologists
|
Flock Mortality Monitoring: A Management ToolDetlef K. Onderka Agri-Food Surveillance Systems Alberta Department of Agriculture, Food & Rural Development
We have applied morality monitoring in cases of poor boiler flock performance in respect to eveness, weights and mortality. In many of these cases, sporadic lab submissions of selected specimens often fail to reveal the reason for performance insufficiencies. Morality monitoring requires submission of all mortality and culls from a 24 hour period for diagnostic evaluation. In the past we have looked at these specimens on a daily basis throughout the growth cycle. This imposed an impractical workload on the diagnostic facility. Recently, we restricted submission to 3 days post placement, 7 days and weekly intervals thereafter. All mortality and culls from the previous 24 hour period were submitted on the same day every week. The results are represented as the percent distribution of various disease conditions over a period of time. Superimposed is the daily barn mortality. This allows to put the disease occurrence into perspective. It also gives an indication whether or not weekly monitoring is sufficient to explain fluctuations and trends in the daily mortality. The attached examples A and B show a typical pattern with colibacillosis being the primary disease in the first week, although its contribution to the overall mortality is moderate. Sudden death syndrome reaches its peak at 14 days with a subsequent steady decline. Over the same time period, ascites starts to contribute sugnificantly to mortality peaking at shipping time. The difference in total mortality is in the higher incidence of colibacillosis in Case B. Case C was done in response to a high prevalence of ascites throughout the previous growth cycle. This cycle we see a significant contribution of colibacillosis to the total mortality. Ascites was detected by 5 days and peaked at 14 days. Feed salt level was responsible and was corrected in the subsequent decline of ascites. At 21 days, necrotic enteritis was diagnosed and immediately treated. These examples show the weekly mortality monitoring can be used for meaningful interpretation of the significance of disease occurrences. An important component is the daily mortality record, which will indicate to submit additional samples when a sudden increase occurs. |
|
To send us your comments or questions regarding this web site, click here. |