Interactive effect of 2 dietary calcium and phytase levels on broilers challenged with subclinical necrotic enteritis: part 1 - broiler performance, gut lesions and pH, bacterial counts, and apparent ileal digestibility

This study investigated the hypothesis that high dietary calcium (Ca) would stimulate necrotic enteritis (NE) and reduce performance, gut health, and nutrient digestibility, and if increased, phytase would reduce NE. Ross 308 male broilers (n = 768) were randomly distributed to 8 treatments in a factorial arrangement. Factors were NE challenge (no or yes), phytase level (500 or 1,500 FTU/kg using 500 FTU/kg matrix values), and Ca level (0.6 or 1.0% starter, 0.5 or 0.9% grower, 0.4 or 0.8% finisher) with the same level of available P (0.40 S, 0.35 G, and 0.35 F). There were 48 pens, 16 birds per pen and 6 replications. Half of the birds were challenged with Eimeria spp on day 9 and 108 CFU per mL of Clostridium perfringens strain EHE-NE18 on day 14 and 15. Gain was higher in birds fed high phytase on day 14 (P P P P P P AID) of crude protein (CP) (P P C. perfringens count, but it decreased Lactobacillus (P Bifidobacteria (

Interactive effect of dietary calcium and phytase on broilers challenged with subclinical necrotic enteritis: 3. Serum calcium and phosphorus, and bone mineralization

Calcium is chelated by phytic acid and forms phytate-mineral complexes reducing Ca availability and the ability of phytase to hydrolyze phytate. An increased Ca concentration in the gut favors the activity of Clostridium perfringens (C. perfringens). Therefore, it was hypothesized that high dietary calcium with high dietary phytase would decrease serum Ca and P and bone mineralization during necrotic enteritis occurrence. A total of 768 one-day-old Ross 308 male chicks were randomly allocated to 8 treatments with 6 replicate pens, each housing 16 birds. A 2 × 2 × 2 factorial arrangement of treatments was applied: dietary Ca (0.6 or 1.0%), phytase (500 or 1,500 FTU/kg), and challenge (no or yes). Half of the birds (384) were challenged with Eimeria spp. on day 9 and C. perfringens strain EHE-NE18 on day 14 and 15. Blood was collected from 2 birds per pen to determine Ca, P, and parathyroid hormone in the serum. The middle toe, tibia, and femur were excised from 2 birds per pen on day 16 and 29 for determination of ash, breaking strength (BS), and mineral concentration. The challenge decreased (P + in birds regardless of dietary Ca level (day 16). There was a challenge × Ca interaction (P P P P P P

Dietary calcium and meat and bone meal as potential precursors for the onset of necrotic enteritis

Necrotic enteritis (NE) is an enteric disease of poultry caused by Clostridium perfringens (C. perfringens). The incidence of NE has increased in several countries as a result of restrictions on the use of in- feed antibiotics. This disease may be triggered by a combination of coccidiosis and the presence of undigested nutrients in the hindgut providing nutrients and high pH that favour the proliferation of patho-gens. Meat and bone meal (MBM) inclusion rates above 4% and higher dietary calcium (Ca) inclusion rates above 1.0% may potentially favour the overgrowth of enteric pathogens, including C. perfringens. High levels of elastin, collagen and keratin from MBM are refractory to gastric digestion and may act as nutrient substrates for C. perfringens. Such proteins are metabolised by C. perfringens by putrefactive fermenta-tion, producing trimethylamine and ammonia, that affect gut health and increase the pH of digesta. Digesta pH may become elevated by feeding a diet high in Ca, as this nutrient has a high acid-binding capacity. Calcium interacts with phytic acid, forming mineral-phytate complexes that decrease the activity of exogenous dietary phytase. This reduces digestion and increases the influx of nutrients into the hindgut. Similarly, smaller particle sizes (dg

Effects of meat and bone meal, phytase and antibiotics on growth performance in broiler chickens during necrotic enteritis challenge

Meat and bone meal (MBM) is a valuable source of protein, calcium and available phosphorus for broiler diets (Anwar et al., 2016). The use of MBM in broiler diets at levels above 50 g/kg minimizes the need for inclusion of inorganic P, thus reducing feed cost. Potential indigestibility of protein in MBM (Kim et al., 2012) may act as a predisposing factor for necrotic enteritis (NE)

Effect of Meat and Bone Meal, Phytase and Antibiotics on the Ash Content and Breaking Strength of Broiler Femurs, Tibia and Toe

Worldwide pressure to remove in-feed antibiotics from the poultry industry has resulted in heightened presence of the disease necrotic enteritis (NE) in broilers. Meat and bone meal (MBM) is readily used in broiler diets as a good source of protein, calcium and phosphorus, but it is also a predisposing factor for NE. A potential alternative to both antibiotics and MBM is the enzyme phytase, due to its ability to enhance nutrient digestion, particularly calcium and phosphorus. Enhancing mineral utilization and limiting nutrient availability for feeding pathogenic bacteria in the gut. The aim of this study was to use analysis of bone formation as a tool to assess the effects of phytase, MBM and antibiotics in broilers challenged with NE. Tibia and femur breaking strength and ash content and toe ash content was measured in NE challenged Ross 308 broilers (n=96) fed diets either with or without MBM, with or without antibiotic and either 500 or 1500 FTU/kg phytase, on d42 post-hatch. Results showed that MBM inclusion increased the tibia and femur ash content (P = 0.003 and P = 0.002, respectively) and breaking strength (P = 0.001). Toe ash content was highest in birds fed the low phytase level with antibiotic, as illustrated by a phytase x antibiotic interaction (P=0.031). Antibiotic had very little effect on bone ash content or strength. In conclusion, toe ash analysis suggests phytase has potential as a replacement for MBM, but further investigation is warranted into its ability to improve tibia and femur formation

Response to meat and bone meal, phytase and antibiotics on gut permeability, nutrient digestibility and caecal microflora in broiler chickens during a necrotic enteritis challenge

Necrotic enteritis (NE) is an enterotoxaemia of poultry with a significant economic effect on poultry production. Currently, antibiotics effectively prevent NE, but there is a global push for reduced reliance on the use of in-feed antibiotics (Castanon, 2007). Preventative treatments focus on the predisposing factors that instigate the disease. One such factor is meat and bone meal (MBM). The ingestible proteins in MBM (Kim, et al., 2012) cause production of toxic metabolites via proliferation of putrefying bacteria, such as highly proteolytic C. perfringens (Sharma, et al., 2017). Supplementing broiler diets with a 'superdose' of phytase has previously been shown to improve performance in NE challenged birds. The aim of this study was to investigate the effects of phytase in NE challenged birds fed MBM based diets, on gut permeability, nutrient digestibility and caecal microflor

Effects of meat and bone meal, phytase and antibiotics on hematological indices and bone integrity in broiler chickens during necrotic enteritis challenge

This study was designed to evaluate the effect of meat and bone meal (MBM), phytase (PHY) and antibiotics (AB) on bone integrity and hematological indices of chickens during necrotic enteritis (NE) . Ross 308 male day-old chicks (n = 672) were fed 8 diets in a2 × 2 × 2 fac-torial arrangement of treatments

The influence of two dietary calcium and phytase levels on the lesion scores, gut pH, gut permeability and serum calcium and phosphorus of broiler chickens challenged with necrotic enteritis

Calcium forms the bulk of minerals added to poultry diets. It is chelated by phytic acid and forms phytate-mineral complexes reducing Ca availability and the ability of phytase enzyme to hydrolyse phytate. High dietary Ca has been implicated in the pathogenesis of necrotic enteritis as it increases gut pH and buffering capacity and decreases uptake of other nutrients. It was hypothesised that high dietary calcium and phytase would favour the proliferation of Clostridium perfringens

Influence of meat and bone meal, phytase, and antibiotics on broiler chickens challenged with subclinical necrotic enteritis: 1. growth performance, intestinal pH, apparent ileal digestibility, cecal microbiota, and tibial mineralization

This study investigated the influence of meat and bone meal (MBM), phytase, and antibiotics (AB) on the performance, intestinal pH, ileal digestibility, cecal microbiota, and tibial mineralization in Ross 308 broilers challenged with necrotic enteritis (NE). A total of 672-day-old male Ross 308 chicks were allocated to 8 treatments with 6 replicate pens, with 14 birds each. The study employed a 2 × 2 × 2 factorial arrangement of treatments: MBM (no or yes), AB (no or yes, zinc bacitracin + salinomycin), and phytase level (500 or 1,500 FTU/kg; both using 500 matrix recommendations). Diets were based on wheat-soybean meal-canola meal. All birds were challenged with Eimeria spp on day 9 and Clostridium perfringens (C. perfringens) strain EHE-NE18 on day 14 and day 15. On day 21 (postchallenge), birds fed MBM had reduced weight gain (WG; P P P P P P

Influence of meat and bone meal, phytase, and antibiotics on broiler chickens challenged with subclinical necrotic enteritis: 2. intestinal permeability, organ weights, hematology, intestinal morphology, and jejunal gene expression

Undigested proteins entering the hindgut may favor the proliferation of Clostridium perfringens. Using phytase to eliminate the need for meat and bone meal (MBM) as a P source may reduce potential infection with C. perfringens. A study was conducted to determine the impact of MBM, phytase, and antibiotics (AB) on intestinal permeability and morphology, organ weights, and jejunal gene expression in Ross 308 chickens challenged with subclinical necrotic enteritis (NE). Male Ross 308-day-old chicks (672 each) were randomly allocated to 8 treatments with 6 replicate pens each housing 14 birds. A 2 × 2 × 2 factorial arrangement of treatments was used: MBM (no or yes); AB (no or yes—Zn bacitracin 100 in S and 50 ppm in G/F and salinomycin Na 60 ppm in all phases); phytase (500 or 1,500 FTU/kg, both using 500 FTU matrix values) using wheat-SBM-canola meal diets. Birds were challenged with Eimeria spp on day 9, and C. perfringens strain EHE-NE18 on day 14 and 15. An AB × MBM interaction (P P > 0.01) was detected for lymphocyte counts being lower with MBM and AB compared to MBM without AB. A phytase × AB interaction ( 0.01) was detected for lymphocyte counts being lower with MBM and AB compared to MBM without AB. A phytase × AB interaction (P P P P P P P > 0.05). Inclusion of MBM decreased expression of MUC2 ( 0.05). Inclusion of MBM decreased expression of MUC2 (