Probiotics are nonpathogenic bacteria that can promote bird health by reducing pathogen colonization. Researchers have previously demonstrated that the avian immune response can be modulated with probiotics, which may provide a mechanism for the reported reductions in pathogens. We examined phagocyte oxidative burst and cell proliferation of vaccinated broilers administered probiotics. We hypothesized that the combination of probiotic bacteria and a vaccine would affect immune function. Two studies were conducted to evaluate this interaction in broilers. Treatments consisted of a negative control, probiotic, vaccine, or a probiotic + vaccine. Peripheral blood was collected on d 7, 14, and 21 of age. Heterophils and monocytes were evaluated for oxidative burst and lymphocytes were assayed for proliferation. In study 1, heterophil oxidative burst was higher (P ≤ 0.05) in each treatment that received probiotic on d 14 when compared with the negative control. On d 21, an enhanced (P ≤ 0.05) heterophil oxidative burst was observed in the probiotic treatment when compared with the other treatments. On d 14, monocyte oxidative burst was greater (P ≤ 0.05) in the probiotic + vaccine treatment when compared with all other treatments. An increase (P ≤ 0.05) in lymphocyte proliferation was observed among all treatments on d 7 when compared with the negative control. Both vaccine treatments had significant lymphocyte proliferation on d 14 when compared with the negative control. In study 2, the probiotic treatment was associated with greater levels in heterophil oxidative burst on d 7 when compared with all other treatments. On d 21, an increase (P ≤ 0.05) in heterophil oxidative burst was seen in the vaccine treatment when compared with the negative control. On d 7, increased (P ≤ 0.05) monocyte oxidative burst was observed in the vaccine treatment when compared with the negative control. No significant differences were observed in lymphocyte proliferation in any of the treatment groups. These data suggest that probiotics can modulate the immune response and may play a role in vaccination.

Two separate performance trials were conducted to determine the effects of postpelleting feed or drinking water application of a Lactobacillus-based probiotic, alone or in combination with a phytogenic product, on growth parameters of broilers fed medicated or nonmedicated diets. Trial 1 consisted of 1,000 straight-run broilers that were randomized, placed in floor rearing pens, and fed medicated diets. At the conclusion of the experiment, BW of broilers receiving the probiotic were not different (P > 0.05) when compared with control broilers. In trial 2, stocking densities were increased to simulate local industry rearing practices, resulting in a total placement of 1,880 chicks in the same rearing facility. Broilers in trial 2 were fed nonmedicated diets. Broilers administered the probiotic by intermittent drinking water application had increased (P < 0.05) BW and improved FCR (P < 0.05) through d 40 compared with control birds. Similarly, broilers receiving the phytogenic product had reduced (P < 0.05) FCR at d 40 compared with control broilers. We conclude that probiotic administration, alone or in combination with a phytogenic product, has the potential to influence broiler performance during commercial grow-out.

We investigated the effects of a phytogenic feed additive (Digestarom® P.E.P. MGE) on growth performance, processing yield, fillet composition, and survival of pond-raised channel catfish. Fifteen 0.4 ha ponds were stocked with 14,820 catfish (126 g/fish) per ha. Fish in control ponds were fed a 32% crude protein commercial floating diet whereas fish in test ponds were fed the same diet supplemented with Digestarom P.E.P. MGE at 200 g/ton. In a second study, ten 0.04 ha ponds were stocked at a similar density with fish that averaged 68 g/fish. At the end of the 6-mo study, there was no significant difference in the amount of feed fed or the amount of weight gained between the control and Digestarom P.E.P. MGE fed fish. Food conversion ratio, net yield, and survival were also similar between the two groups. Carcass, fillet, and nugget yield were similar. Fillet proximate analysis revealed that fillet fat was lower (P < 0.01) whereas fillet protein tended to be a little higher (P < 0.10) in treated fish. In conclusion, there was a significant reduction in the amount of fillet fat in Digestarom P.E.P. MGE fed fish. Improved fillet composition (higher protein and lower lipid) is of commercial importance.

The current experiment was conducted to determine the effect of mycotoxin-contaminated diets with aflatoxin (AFLA) and deoxynivalenol (DON) and dietary inclusion of deactivation compound on layer hen performance during a 10-wk trial. The experimental design consisted of a 4 × 2 factorial with 4 toxin levels: control, low (0.5 mg/kg AFLA + 1.0 mg/kg DON), medium (1.5 mg/kg AFLA + 1.5 mg/kg DON), and high (2.0 mg/kg AFLA + 2.0 mg/kg DON) with or without the inclusion of deactivation compound. Three hundred eighty-four 25-wk-old laying hens were randomly assigned to 1 of the 8 treatment groups. Birds were fed contaminated diets for a 6-wk phase of toxin administration followed by a 4-wk recovery phase, when all birds were fed mycotoxin-free diets. Twelve hens from each treatment were subjected to necropsy following each phase. Relative liver and kidney weights were increased (P < 0.05) at the medium and high toxin levels following the toxin phase, but the deactivation compound reduced (P < 0.05) relative liver and kidney weights following the recovery period. The high toxin level decreased (P < 0.05) feed consumption and egg production during the toxin period, whereas the deactivation compound increased (P < 0.05) egg production during the first 2 wk of the toxin phase. Egg weights were reduced (P < 0.05) in hens fed medium and high levels of toxin. An interaction existed between toxin level and deactivation compound inclusion with regard to feed conversion (g of feed/g of egg). High inclusion level of toxins increased feed conversion compared with the control diet, whereas deactivation compound inclusion reduced feed conversion to a level comparable with the control. These data indicate that deactivation compound can reduce or eliminate adverse effects of mycotoxicoses in peak-performing laying hens.

An experiment was conducted to determine the effect of dietary inclusion of Mycofix Select (Biomin GmbH, Herzogenburg, Austria) on discrete egg parameters and quality characteristics of hens fed mycotoxin-contaminated diets (aflatoxin; AFLA) and deoxynivalenol (DON)) during a 10-wk trial. A 4 × 2 factorial design was used with 4 contamination levels: control, low (0.5 mg/kg of AFLA + 1.0 mg/kg of DON), medium (1.5 mg/kg of AFLA + 1.5 mg/kg of DON), and high (2.0 mg/kg of AFLA + 2.0 mg/kg of DON) with or without the inclusion of mycotoxin deactivating compound. Three hundred and eighty-four 25-wk-old laying hens were housed 3 per cage. Birds were fed contaminated diets for a 6-wk phase of toxin administration followed by a 4-wk recovery phase, when all birds were fed mycotoxin-free diets. Parameters evaluated included egg weight, Haugh unit value, specific gravity, eggshell thickness, egg shape index, and relative albumen and yolk weights. Albumen height and Haugh unit value were depressed (P < 0.05) at the high mycotoxin level 2 wk postinclusion. Egg weight was significantly reduced (P < 0.05) with the high toxins level by the third week of toxin administration and remained throughout the study during toxin administration. Egg shape index indicated a variation (P < 0.05) in shape with all toxin levels compared with the control. Relative yolk weight was decreased (P < 0.05) by the high toxin level. An interaction existed between the deactivating compound inclusion and toxins level with regard to specific gravity. Following the toxin phase, the deactivating compound inclusion increased (P < 0.05) egg specific gravity in the control and low toxin groups whereas a decrease (P < 0.05) was observed at the high toxin level. These data indicate that mycotoxins present in feed can reduce egg quality, size, yolk weight, and alter egg shape and that inclusion of a mycotoxin deactivating compound can ameliorate some of the negative effects of mycotoxin consumption.