Comparative efficacy of different natural products based on liquid Quillaja extract administered in the feed for the control of necrotic enteritis in chickens

Necrotic enteritis (NE) is one of the most concerning diseases in the poultry industry. Economic losses of NE ascend up to 40% of commercial broilers and are associated with the effect of Clostridium perfringens (CP) overgrowth in productivity. Treatment for NE administered in drinking water is more advantageous than feed treatment. Therefore, it is important to offer new natural solutions. The study was conducted at Southern Poultry Research Inc. using 0- to 28-day-old Cobb 500 male chicks. There were 72 cages with 8 birds/cage and 9 cages/treatment. On d 14, all birds except control were orally inoculated with ~5,000 oocysts of Eimeria maxima per 1-mL dose and from 19 to 21 d received an inoculum of ~108 cfu/mL CP. Lesion score (0 to 3 score), feed intake, body weight gain (BWG), and feed conversion ratio (FCR) were recorded. Blood samples for FITC-d analysis were taken on d 21 (2 birds/cage). Groups were control (CON), control/challenged (POS), Maxiban (MAX), Quillaja-oregano emulsion (QOE1: 0.12 g/L, ratio 6:1), Quillaja-oregano emulsion (QOE2; 0.3 g/L, ratio 1:6), and Quillaja liquid solution (QLS; 0.06 g/L). The NE challenge had a clear effect on performance as observed by the lower BWG and FCR in POS versus CON; between 14 and 20 d, birds in POS had a 65% reduction in BWG versus CON. Compared with untreated birds (POS), QLS had a significant reduction (16%) and increase (23%) in FCR and BWG, respectively. All treatments had lower FCR than POS, however, QLS and MAX had the lowest values. Following the challenge, between 14 and 28 d, there was a noticeable difference in BWG of both QLS and QOE2 groups versus POS with an increase of 37.8 and 13.6%, respectively. The average lesion score in MAX and QLS was 51.1 and 44.6% lower than POS, respectively. The FITC-d was 10.4% lower than POS in QOE2, whereas QOE1 group showed a 9.4% reduction in FITC-d versus POS. In conclusion, there was a clear effect of Eimeria and C. perfringes challenge on the performance of birds. The most promising results were obtained using QLS and QOE2 as natural treatments.

Key Words: Quillaja extract, essential oil, necrotic enteritis, leaky gut, chickens.

Presented at the 10th Symposium on Gut Health in Production of Food Animals 2022, St. Louis, USA.