Five years dynamic of Salmonella enterica in commercial poultry farms with and without probiotics application

Probiotics application in commercial livestock serves for several needs such as improve production performance, promote animal health and support food safety in animal production. Numerous studies indicated the effect of probiotics on Salmonella reduction in chicken but most of publications imply only in experimental study scale. The insufficient information on real farm situation poses Salmonella control by probiotics use in commercial farms still obvious. To answer this question, we analyzed the data collection harbored from an ISO17025: 2005 service laboratory in Thailand, scope on probiotics application and Salmonella occurrence.

Data were analyzed from the collection of samples submitted from 4 commercial chicken breeder farms. Each farm submitted samples continuously for at least 5 consecutive years. In order to compare effect probiotics on Salmonella occurrence, 2 sets of data were generated in comparison of farms probiotics usage status; set 1) Early stage of probiotics application (EPA) farm and Continuous probiotics application (CPA1) farm (2007 - 2011), set 2) Continuous probiotics application (CPA-2) farm and non-probiotics application (NPA) farm (2014 - 2018).

A total of 902 samples were included in data set 1 and 4,222 samples in data set 2. To reduce the bias of data, environmental samples were excluded, only fecal samples (CPA 1, CPA-2 and EPA) and boot swab samples (NPA) were processed in the analysis. In data set 1, the percentage of Salmonella positive sample in EPA farm gradually decreased after the onset of the probiotics (average 34.18% to 18.82%). While the average percentage of positive sample during the identical 5 years in CPA-1 farm was 1.01% and the variation of positive sample is between minimum 0% to maximum 2.46%. In data set 2, the 5-years average occurrence in CPA-2 farm was 3.70% (minimum 2.40%, maximum 5.68%) and 5.33% (minimum 2.75%, maximum 8.66%) in NPA farm. Serovar information of samples also included in the analysis. The most present serovar was changed year by year and different between farms.

In conclusion, the information from data set 1 and 2 suggested that application of probiotics possible to reduce the Salmonella occurrence in commercial breeder farm and the continuous application of probiotics could stabilize the farm Salmonella status.

However, according to the data was obtained from the commercial laboratory service, multiple limitations are noted. The data in this study could not represent the chicken population in the farm since it was obtained from customer submission samples. The variation between the type of sample from each farm was depended on farm’s Salmonella monitoring and management. This information may be affected by other Salmonella control procedures such as vaccination and farm management during the period of analysis bioactives against sub-acute ruminal acidosis (SARA) and mastitis.
 
Keywords: probiotics, Salmonella enterica, commercial poultry farm.

Abstract presented at the 3rd International Symposium on Alternatives to Antibiotics 2019.