Abstract
Salmonellosis in broilers is a disease with considerable economic implications for the poultry industry. As a foodborne illness, it also poses a public health risk due to potential cross-contamination. Probiotics have been proposed as alternative feed additives aiming to enhance growth, livestock productivity, and overall health. This study investigated the dietary impact of Lactococcus lactis JNU 534 on growth performance, blood characteristics, internal organ weight, and meat quality in broilers inoculated with Salmonella enteritidis (SE). A total of 96 one-day-old Arbor Acres broiler chickens, comprising both sexes, were challenged with SE and randomly assigned into two treatment groups and housed in eight pens (four pens per each treatment, with 12 birds per pen). They were fed a commercial broiler diet for 35 days. The two dietary treatment groups consisted of a control group receiving commercial feed, and a treatment group receiving commercial feed supplemented with 0.3% L. lactis JNU 534. Probiotic supplementation significantly improved average body weight gain, feed efficiency, and carcass yield compared to the control group (p < 0.05). Notably, the abdominal fat pad was significantly reduced in the probiotics group (p < 0.05). Meat quality assessments revealed no significant differences between the groups in terms of meat pH, cooking loss, drip loss, and water-holding capacity. These findings suggest that L. lactis JNU 534 is a promising candidate to mitigate the negative effects of Salmonella on growth performance in commercial broiler farms, without adversely affecting health. Extending the research to other types of livestock could help confirm its wider use as an alternative to antibiotics.