Phytogenic blend protective effects against microbes but affects health and production in broilers

The aim of this study was to determine whether addition of a phytogenic blend in the feed of broilers to replace conventional antimicrobials as a performance enhancer would improve or maintain productive efficiency. The phytogenic blend was based on curcuminoids, cinnamaldehyde and glycerol monolaurate. We used 480 birds divided into three groups with eight repetitions per group and 20 birds per repetition. The groups were identified as antimicrobial-treated: basal feed with antibiotics and coccidiostatic agents; phytogenic blend: basal feed with blend; and control, only basal feed. Zootechnical performance was measured on days from 1 to 42, with body weight measured at days 1, 7, 21 and 42. We collected excreta for parasitological analysis and total bacterial counts to determine if the phytogenic blend had kept the bacteria and coccidia in counts smaller or similar to that resulting from use of conventional performance enhancer. Other variables were also measured to complement our research, i.e., if the consumption of bend is good for the health of the birds (without causing toxicity and negatively altering the metabolism and intestinal morphometry) and does not interfere in the quality of the meat. Because the bacteria are often opportunistic, we challenged all birds at 23 days of age with high doses of oral oocysts (28,000 oocysts). Birds supplemented with the blend showed inferior performance compared to birds in the control and antimicrobial treated group (P < 0.05). We found a smaller number of oocysts of Eimeria spp. in the excreta at 42 days in the treatment with blend and antimicrobial treated group (P < 0.05). In terms of total bacterial counts, there were lower counts in the birds of the blend group than in the control group (P < 0.05). The blend increased the yellow intensity and the luminosity of the meat (P < 0.05), as well as cooking weight losses (P < 0.05) compared those of the control. We observed higher total levels of saturated fatty acids in meat from the blend and antimicrobial treated group (P < 0.05), as well as lower levels of monounsaturated fatty acids in the blend group (P < 0.05). The inclusion of a phytogenic blend to replace conventional antimicrobials and anticoccidial agents in the diet of chickens was able to control bacteria as well as coccidia; however, it ends up harming health and production.