Abstract:
Salmonella remains a persistent public health concern both in the developed and developing countries. Several reports on the prevalence of Salmonella in food, food production environment and human cases have been found both in developing and developed countries. A randomized controlled field trial based on parallel group design was conducted from January, 2018 to July, 2018 with the objectives to investigate the preventive effect of supplementing Effective Microbial (EM) in diet of beef cattle in reducing the presence and burden of Salmonella in their lymph nodes. The treatment group exposed to feed supplemented by EM and non- exposed (Control) groups was established. The Chercher Oda-Bultum Farmers Union beef Farm was used for the study purpose. The animals were slaughtered after follow up periods of 90, 100 and 115 days at Haremaya University abattoir. Lymphnode samples was collected from which mesenteric LN (n = 130), Subiliac LN (n = 130) and total (n = 260). Isolation and enumeration of Salmonella were conducted. Prevalence and load determination analyzed in laboratory total significant reduction (53.00%) relative and (37.00%) absolute risk reduction among control and treatment group (P=0.000) were observed. The significant shift in concentration of Salmonella in LNs (MLN and SLNs) due to the influence of supplementation EM (P = 0.000) age in MLN (P = 0.000) and body condition (P=0.025) in SLN, duration of treatment for both have significant interaction (P=0.000). Using EM in the diet of beef cattle is effective in reducing risk of Salmonella in both prevalence and burden. Further study in different agro ecology, season, breed, production system should be conducted. Using animal model to investigate the interaction of EM, Salmonella and bovine immune system will also be important.
