Efficacy of Bacillus subtilis and bacitracin methylene disalicylate on growth performance, digestibility, blood metabolites, immunity, and intestinal microbiota after intramuscular inoculation with Escherichia coli in broilers

Abstract

This experiment was conducted to evaluate the effect of Bacillus subtilis (BS) on broiler performance and health after intramuscular inoculation with E. coli and compare its effect with a growth promoter antibiotic. In a completely randomized design manner, 360 male Ross 308 chicks were divided into 6 treatments and 5 replicates of 12 chicks in each replicate. Experimental treatments included control diet, control + E. coli (0.5 mL of culture containing 108 CFU of E. coli/ml), control + 0.1% BS, control + 0.05% bacitracin methylene disalicylate (BMD), control + E. coli and BS, and control + E. coli and BMD in a factorial arrangement (3 × 2). Addition of BMD or BS to the control diet significantly (P < 0.01) increased body weight and decreased FCR, but E. coli challenge adversely reduced (P < 0.01) body weight and increased FCR, so that the addition of BMD or BS did not compensate growth reduction. E. coli challenged chicks had the lowest vaccine titers for ND, IB, AI, and IBD and the highest were observed in chicks fed BS. The E. coli challenge significantly (P < 0.01) increased albumin, globulin, cholesterol, triglyceride, LDL, ALT, and ALP indices. Addition of BMD and BS decreased albumin and globulin in challenged chick's plasma but had no effect on plasma lipid profile concentration. The E. coli challenge decreased villus height and increased crypt depth and goblet cell numbers significantly (P < 0.01). In birds subjected to BMD or BS, crypt depth decreased and villus height increased (P < 0.01), compared with the control diet. Challenge of E. coli significantly (P < 0.01) increased the bacterial population of E. coli, coliforms, and Salmonella in cecal parts of broilers' intestines. In challenged birds receiving BMD or BS, E. coli, coliform, and Salmonella populations of ceca showed a significant (P < 0.01) reduction. Both BMD and BS increased the digestibility of nutrients significantly (P < 0.01), but a reduction was observed in E. coli challenged groups. Results of the study suggest that spore-forming probiotics are partially effective in unsuitable rearing situations such as colibacillosis in which the load of harmful bacteria is high.

Probiotics (Direct-Fed Microbials) in Poultry Nutrition and Their Effects on Nutrient Utilization, Growth and Laying Performance, and Gut Health: A Systematic Review

“…B. subtilis , a spore-forming bacterial species, are partially effective, even in unsuitable farming conditions, in improving nutrient digestibility. When birds were challenged with the intramuscular inoculation of E. coli (0.5 mL of culture containing 10 8 CFU of E. coli ), the B. subtilis probiotic-fed birds showed a significantly higher digestibility of crude fiber, CP, and GE [ 51 ]. The enhanced digestibility and absorption of nutrients may be attributed to the production of extracellular enzymes by the vegetative form of B. subtilis [ 52 ].…”

Comparative studies on the effects of lincomycin and bacitracin on hematobiochemical and immunological parameters in broiler chickens

“…Additionally, zinc bacitracin in the diet of broilers chickens was found safe as the liver function tests and protein picture were not altered (El-Bahr et al 2013). Moreover, bacitracin supplement in ration induced a non-significant elevation in total protein, albumin, total globulin, γ globulin,  and α globulin (Manafi et al 2017). Recently, the above-mentioned results were supported by another study that stated that using bacitracin at therapeutic dose induced nonsignificant increase in serum total protein, albumin, total protein, albumin total, α,  and γ globulin in broiler chickens (Adel 2018).…”

“…Similarly, in ducks, zinc bacitracin in diets induced lower in the level of serum total lipid and cholesterol concentration (Wu et al 2013). Manafi et al found that bacitracin methylene disalicylate supplement in ration induced the nonsignificant changes in cholesterol, triglyceride (Manafi et al 2017). Similarly, zinc bacitracin and bacitracin methylene disalicylate induced significant reduction concentrations of serum lipid profiles (Ogboko 2010) and (Chowdhury et al 2018), respectively.…”

Bacillus subtilis como probiótico en avicultura: aspectos relevantes en investigaciones recientes

“…Otros estudios sugieren que los probióticos formadores de esporas favorecen situaciones de crianza, donde la carga bacteriana por colibacilosis es alta. Al respecto Manafi et al, (2016) evaluó el efecto de B. subtilis y Disalicilato metileno bacitracina en el rendimiento y salud de los pollos machos Ross, después de la inoculación intramuscular con E. coli (0,5 mL de cultivo que contiene 10 8 UFC de E. coli/mL); provocando la disminución de la altura de las vellosidades y un incremento de presencia de las colonias de E. coli, coliformes y Salmonella en partes cecal de los intestinos de los pollos. El uso del Disalicilato metileno bacitracina sólo ayudó a disminuir la presencia de las bacterias patógenas, pero B. subtilis además aumentó la digestibilidad de los nutrientes y la altura de las vellosidades intestinales (Manafi, Khalaji, Hedayati, & Pirany, 2016).…”

“…al., (2008) los microorganismos más usados son Lactobacillus sp., Streptococcus faeccium, Bacillus subtilis, Bacillus licheniformis, Bacillus stearothermophyllus y Saccharomyces cerevisiae. Sin embargo, el género Bacilus destacan como probiótico, por la acción de las enzimas hidrofílicas extracelulares que actúan sobre polisacáridos, ácidos nucleicos y lípidos; empleando estos como fuentes de carbono, donadores de electrones y productores de antibióticos (Forte et al, 2016;Manafi et al, 2016).…”