Anjan Mondal, Azimul Haque, Partha Das, Venket M Shelke and Prakash C Saini, Kemin Industries South Asia Pvt. Ltd.
Enteric diseases are one of the major economically significant problem to poultry industry. This occurs because of huge economic loss due to lower production, increased mortality and the risk of contamination of poultry products for human consumption. Necrotic enteritis (NE) is the most common enterotoxemic disease in broiler chickens caused by Clostridium perfringens.
NE leads to increased mortality at a rate up-to 50% and is responsible for subclinical infection which causes chronic damages of intestinal mucosa leading to poor performance, reduced body weight and poor FCR. The total economic loss due to NE outbreak globally was estimated to be over 2 billion dollars annually. Generally, small number of Clostridium perfringens are always found in intestinal tract of healthy broiler birds. However, the ability of Clostridium perfringens to cause disease is linked to predisposing factors like incidence of coccidiosis and creating a favorable condition for their multiplication. When the Clostridium perfringens number increases in intestinal tract, toxins are produced. In poultry, NE is caused by Clostridium perfringens type A strains which produce α-toxin and pore forming toxin–NetB. This resulted in an extensive use of on-top application of antibiotic growth promoters (AGP) at sub-therapeutic doses in poultry diets. This not only improves the poultry growth and feed conversion efficiency, but also controls enteric disease outbreak. There is an increasing concern over the use of antibiotics due to possible development of antibiotic resistance. The demand for reduced and limited use of antibiotics in poultry diet has caused an increasing demand for suitable antibiotic alternative supplements to control and prevent NE outbreaks in poultry.
CLOSTAT™ is an active microbial containing Bacillus subtilis PB6, having direct inhibitory action against Clostridium perfringens. Bacillus subtilis PB6 is isolated from healthy chicken gut that had been shown in-vitro to produce antimicrobial substances with broad activity against various strains of Clostridium sp., Escherichia coli and Campylobacter sp. Bacillus subtilis PB6 is known to secrete surfactins having antimicrobial activity. These surfactins are amphipathic cyclic lipoheptapeptides belonging to nonribosomal peptide family of natural products, having exceptional emulsifying capabilities as well as antibacterial, antiviral and antitumor properties. A study was conducted in Bangladesh to evaluate the efficacy of dietary incorporation of CLOSTAT™ on production parameters like body weight, feed conversion ratio (FCR), European Efficiency Factor (EEF) and cost of production (COP) per kg live weight in broilers, in comparison with commonly used AGP, namely Avilamycin.
The trial design and dosage of treatment groups are detailed in Table-1.
MATERIALS AND METHODS
The trial was conducted in Bangladesh with 1500 straight run broiler birds (Cobb-500) which were randomly divided into 3 groups, each with 4 replicates of 125 birds per replicate for a period of 29 days. The birds were maintained in deep litter system. All the groups were given a regular corn soya-based pellet diet commonly used for commercial broiler birds.
RESULTS AND DISCUSSION
The trial results indicated that CLOSTAT™ 11 Dry group was a superior alternative to Avilamycin, providing a significant (P≤0.05) weight gain of 69g per bird with better FCR by 8-points (Fig.1 and Fig.2). The dietary supplementation of CLOSTAT™ 11 Dry in combination of Avilamycin has shown improved weight gain of 49g per bird and 6-points better FCR when compared to Avilamycin group (Fig.1 and Fig.2). CLOSTAT™ 11 Dry and CLOSTAT™ 11 Dry with Avilamycin combination groups have shown higher EEF at 42-points and 30-points respectively with better economic returns for production of one kg live weight when compared to Avilamycin group (Fig.3 and Fig.4). The dietary supplementation of CLOSTAT™ 11 Dry alone and in combination with AGP for 500 broiler birds gave an additional revenue of 2,438 BDT and 1,938 BDT respectively over Avilamycin (Table – 2).
Dietary supplementation of probiotics has shown improved body weight gain, reduced mortality and enhanced feed efficiency resulting in an increased broiler productivity. Bacillus subtilis PB6 improves broiler growth and performance, and it can be used as an AGP replacement. Jayaraman, et. al., demonstrated that supplementation of Bacillus subtilis PB6 reduced FCR significantly and showed numerical improvement in body weight gain, particularly in birds challenged with Clostridium perfringens.
Fig 1: Body weight of CLOSTAT™ 11 Dry and CLOSTAT™ 11 Dry with Albamycin combination groups improved significantly (P≤0.05) when compared to Albamycin group.
Fig 2: CLOSTAT™ 11 Dry group and CLOSTAT™ 11 Dry with Avilamycin combination group have a significant (P≤0.05) FCR over Avilamycin group.
Fig 3: CLOSTAT™ 11 Dry group and CLOSTAT™ 11 Dry with Avilamycin combination have shown higher EEF at 42 points and 30 points respectively when compared to Avilamycin group
Fig. 4: CLOSTAT™ 11 Dry group and CLOSTAT™ 11 Dry with Avilamycin combination have better economic returns for production of 1 kg live weight when compared to Avilamycin group
To conclude, the present study demonstrated that CLOSTAT™ 11 Dry is an effective tool to replace the antibiotic growth promoter (Avilamycin) in maintaining the optimal gut health and providing superior production parameters in broilers resulting in better economical returns.